JP7287582B1 - Encapsulating resin composition and electronic device - Google Patents

Abstract

The encapsulating resin composition of the present invention is a encapsulating resin composition containing a coloring agent, a thermosetting resin, a curing agent, and an inorganic filler. containing carbon particles having a specific resistance value of 1.0 × 10 Ω cm or more and 1.0 × 10 14 Ω cm or less when the solid content of the sealing resin composition is It is 0.05% by weight or more and 5% by weight or less with respect to the whole.

Description

The present invention relates to an encapsulating resin composition and an electronic device.

A black coloring agent is used in the encapsulating resin composition for the purpose of improving laser markability. Carbon black, titanium-based black pigments, and transition metal compounds such as black iron oxide (iron black) are used as black colorants.

As an example, in Patent Document 1, in addition to excellent properties such as mechanical properties, heat resistance, chemical resistance, and dimensional stability, while ensuring electrical insulation, the surface resistivity of the sealing molding is improved. An encapsulating resin composition is described which can be tightly controlled in the semiconducting region.
As another example, Patent Document 2 discloses that even in an electronic component device such as a semiconductor device that has excellent laser markability and electrical characteristics and has a narrow distance between pads or between wires, a short failure due to a conductive material does not occur, and A sealing epoxy resin composition excellent in moldability, reliability, and package surface appearance, and an electronic component device having an element encapsulated therewith are disclosed.

JP 2012-97282 A Japanese Patent Application Laid-Open No. 2001-335677

On the other hand, when the inventors of the present invention investigated the resin composition for sealing as described above, there was room for further improvement from the viewpoint of blackness and dielectric properties.

The present invention has been made in view of such circumstances, and provides a sealing resin composition having good blackness and dielectric properties while ensuring mechanical properties and high-temperature reliability, and the sealing resin composition. An object of the present invention is to provide an electronic device in which a semiconductor element is sealed with a cured product of (1).

As a result of studies, the inventors completed the invention provided below and solved the above problems.

[1]
a coloring agent;
a thermosetting resin;
a curing agent;
an inorganic filler;
A sealing resin composition containing
The coloring material contains carbon particles having a specific resistance of 1.0×10 ¹ Ω·cm or more and 1.0×10 ¹⁴ Ω·cm or less when a load of 20 kN is applied,
The content of the carbon particles is 0.05% by weight or more and 5% by weight or less with respect to the total solid content of the sealing resin composition.
Resin composition for encapsulation.
[2]
In the sealing resin composition according to [1] above,
In the X-ray diffraction spectrum measured by the X-ray diffraction method using CuKα rays as a radiation source, with 2θ on the horizontal axis and diffraction intensity on the vertical axis, a straight line selected by <Method> below was removed as a background. An encapsulating resin composition in which the crystallite size Lc in the c-axis direction of the (002) plane of the carbon particles (the direction perpendicular to the (002) plane) is 50 Å or less, which is required later.
<Method>
(1) In the above X-ray diffraction spectrum with 2θ on the horizontal axis and diffraction intensity on the vertical axis, one of the points at 2θ = 10° or 2θ = 15° and the point at 2θ = 30° or 2θ = Select any one of the 35° points and connect the two selected points with a straight line to create a total of four straight lines.
(2) Select one of the four straight lines created in (1) above.
(3) In the region where 2θ is 10° or more and 35° or less, find the area S surrounded by the straight line selected in (2) above and the X-ray diffraction spectrum located below the straight line.
(4) The steps (2) and (3) are repeated for each of the four straight lines created in (1) above, and the straight line L that minimizes the obtained area S is specified.
(5) Let the straight line L be the background straight line.
[3]
The encapsulating resin composition according to [1] or [2] above, wherein the sulfur content in the carbon particles is 150 ppm or less.
[4]
The encapsulating resin composition according to any one of [1] to [3] above, wherein the carbon particles have a chlorine content of 50 ppm or less.
[5]
In the sealing resin composition according to any one of [1] to [4] above,
The thermosetting resin is selected from the group consisting of novolac type epoxy resins, polyfunctional epoxy resins, phenol aralkyl type epoxy resins, naphthol type epoxy resins, triazine core-containing epoxy resins, and bridged cyclic hydrocarbon compound-modified phenol type epoxy resins. A sealing resin composition containing one or more epoxy resins.
[6]
The encapsulating resin composition according to any one of [1] to [5] above, wherein the curing agent comprises a phenolic resin-based curing agent.
[7]
In the sealing resin composition according to any one of [1] to [6] above,
A sealing resin composition having a flow length of 50 cm or more and 300 cm or less, measured using a mold for spiral flow measurement according to EMMI-1-66, at a mold temperature of 175° C. and a measurement time of 5 minutes.
[8]
In the sealing resin composition according to any one of [1] to [7] above,
Using L ^*, a ^* , b ^* defined by the CIE1976L ^* a ^* b ^* color system of the cured product obtained by curing the encapsulating resin composition by heat treatment at 175°C for 30 minutes, Formula (1) below:
D=[(L ^* −27) ² +(a ^* −(−1)) ² +(b ^* −(−3)) ² ] ^1/2 (1)
A sealing resin composition having a D value of 3.2 or less.
[9]
In the sealing resin composition according to any one of [1] to [8] above,
The ratio ε ₁ /ε ₁₀ of the dielectric constant ε 1 at 1 GHz _of the cured product obtained by curing the sealing resin composition by heat treatment at 175 ° C. for 30 minutes and the dielectric constant ε ₁₀ at 10 GHz is A resin composition for sealing, which is 0.9 or more and 1.2 or less.
[10]
In the sealing resin composition according to any one of [1] to [9] above,
The ratio _δ1 / _δ10 between the dielectric loss tangent _δ1 at 1 GHz and the dielectric loss tangent _δ10 at 10 GHz of the cured product obtained by curing the sealing resin composition by heat treatment at 175°C for 30 minutes is The resin composition for sealing, which is 0.8 or more and 1.1 or less.
[11]
An electronic device in which a semiconductor element is encapsulated with a cured product of the encapsulating resin composition according to any one of [1] to [10] above.

According to the present invention, a semiconductor element is sealed with a sealing resin composition having good blackness and dielectric properties while ensuring mechanical properties and high-temperature reliability, and a cured product of the sealing resin composition. An electronic device is provided.

Hereinafter, embodiments of the present invention will be described in detail.

In this specification, the notation "X to Y" in the description of numerical ranges means X or more and Y or less, unless otherwise specified. For example, "1 to 5% by mass" means "1% by mass or more and 5% by mass or less". In this specification, the term "electronic device" refers to semiconductor chips, semiconductor elements, semiconductor devices, printed wiring boards, electric circuit display devices, information communication terminals, light emitting diodes, physical batteries, chemical batteries, etc., and electronic engineering technology is applied. A structure in which electronic components such as semiconductor elements, resistors, inductors, etc. are mounted on a circuit board and are encapsulated together with a resin composition for encapsulation. including those of

<Resin composition for encapsulation>
First, the encapsulating resin composition of the present embodiment will be described.

The encapsulating resin composition in the present embodiment is a encapsulating resin composition containing a coloring agent, a thermosetting resin, a curing agent, and an inorganic filler. The sealing resin contains carbon particles having a specific resistance value of 1.0×10 ¹ Ω·cm or more and 1.0×10 ¹⁴ Ω·cm or less when a load is applied, and the content of the carbon particles is The resin composition for sealing is 0.05% by weight or more and 5% by weight or less based on the total solid content of the composition.

Colorants used in conventional encapsulating resin compositions include carbon black, titanium-based black pigments, and transition metal compounds such as black iron oxide (iron black), as described above. However, although conventional carbon black has strong tinting strength and low cost, its low resistivity value can cause short circuits between encapsulated electronic components. On the other hand, titanium-based black pigments and black iron oxide (iron black) have a high specific resistance value, and are less likely to cause a short circuit between sealed electronic components, but are expensive.

Here, in the encapsulating resin composition of the present embodiment, the specific resistance value of the coloring material when a load of 20 kN is applied is 1.0×10 ¹ Ω·cm or more and 1.0×10 ¹⁴ Ω·cm or less. is used, and the content of the carbon particles is 0.05% by weight or more and 5% by weight or less with respect to the total solid content of the sealing resin composition, so that conventional carbon black is We have succeeded in obtaining blackness equivalent to that obtained by using titanium-based black pigments and dielectric properties superior to those obtained by using conventional titanium-based black pigments and black iron oxide (iron black).

Each component contained in the resin composition will be described in more detail below.

[Colorant]
The encapsulating resin composition in the present embodiment is a carbon resin having a specific resistance of 1.0×10 ¹ Ω·cm or more and 1.0×10 ¹⁴ Ω·cm or less when a load of 20 kN is applied as a coloring material. Contains particles. As a result, the electrical insulation of the encapsulating resin composition can be improved, and when electronic components are encapsulated using the resin composition of the present embodiment, short circuits between electronic components can be prevented. can be prevented.

(carbon particles)
The lower limit of the specific resistance of the carbon particles contained in the encapsulating resin composition of the present embodiment when a load of 20 kN is applied is 1.0×10 ¹ Ω·cm or more, preferably 1.0×10 Ω·cm or more. It is 10 ² Ω·cm or more, more preferably 1.0×10 ³ Ω·cm or more, and still more preferably 1.0×10 ⁵ Ω·cm or more. When the specific resistance value is equal to or higher than the lower limit value, it is possible to suitably suppress the risk of short circuits in the wiring inside the encapsulating resin composition when kneaded into the encapsulating resin composition.
Further, the upper limit of the specific resistance value of the carbon particles contained in the sealing resin composition in the present embodiment is 1.0×10 ¹⁴ Ω·cm or less, and 1.0×10 ¹³ Ω·cm or less. 1.0×10 ¹² Ω·cm or less, or 1.0×10 ¹¹ Ω·cm or less.

Moreover, the content of the carbon particles contained in the sealing resin composition in the present embodiment is 0.05% by weight or more and 5% by weight or less with respect to the total solid content of the sealing resin composition. As a result, the degree of blackness of the encapsulating resin composition when kneaded into the encapsulating resin composition can be made suitable, and the laser mark property can be made good.

Here, the lower limit of the content of carbon particles contained in the encapsulating resin composition in the present embodiment is preferably 0.05% by weight or more, more preferably 0.1% by weight or more, and still more preferably 0.2%. % by weight or more. When the content of the carbon particles is at least the above lower limit, the blackness of the encapsulating resin composition when kneaded into the encapsulating resin composition can be made more suitable.
Also, the upper limit of the content of carbon particles contained in the encapsulating resin composition in the present embodiment is preferably 5% by weight or less, more preferably 4% by weight or less, and even more preferably 3% by weight or less. When the content of the carbon particles is equal to or less than the above upper limit, the fluidity of the encapsulating resin composition when kneaded into the encapsulating resin composition can be made more suitable.

The carbon particles contained in the encapsulating resin composition of the present embodiment have an X-ray diffraction spectrum measured by an X-ray diffraction method using CuKα rays as a radiation source, with 2θ on the horizontal axis and diffraction intensity on the vertical axis. , the upper limit of the crystallite size Lc in the c-axis direction of the (002) plane (orthogonal to the (002) plane) obtained after removing the straight line selected by <Method> below as the background is 50 Å or less. preferably 40 Å or less, particularly preferably 30 Å or less.

<Method>
(1) In the above X-ray diffraction spectrum with 2θ on the horizontal axis and diffraction intensity on the vertical axis, one of the points at 2θ = 10° or 2θ = 15° and the point at 2θ = 30° or 2θ = Select any one of the 35° points and connect the two selected points with a straight line to create a total of four straight lines.
(2) Select one of the four straight lines created in (1) above.
(3) In the region where 2θ is 10° or more and 35° or less, find the area S surrounded by the straight line selected in (2) above and the X-ray diffraction spectrum located below the straight line.
(4) The steps (2) and (3) are repeated for each of the four straight lines created in (1) above, and the straight line L that minimizes the obtained area S is specified.
(5) Let the straight line L be the background straight line.

When Lc is equal to or less than the above upper limit, when a molded body is produced using the encapsulating resin composition kneaded with carbon particles, chipping and peeling are less likely to occur on the surface of the molded product, and equipment contamination is prevented. It is possible to obtain the effect of being able to prevent it. This is probably because non-graphite type carbon is harder than crystalline graphite and the carbon layer is less likely to peel off.
In addition, when the upper limit of Lc is 40 Å or less, the risk of short circuits in wiring inside the encapsulating resin composition can be suitably suppressed when kneaded into the encapsulating resin composition.
Although the lower limit of Lc is not particularly limited, it is, for example, 3 Å or more, 5 Å or more, 6 Å or more, 7 Å or more, 8 Å or more, and 9 Å or more.

The crystallite size Lc can be determined using the following Scherrer's equation from the half width and diffraction angle of the (002) plane peak in the spectrum obtained from X-ray diffraction measurement.
Lc=0.94λ/(β cos θ) (Scherrer's formula)
Lc: Size of crystallite λ: Wavelength of characteristic X-ray _Kα1 output from the cathode (λ=0.15418 nm when CuKα ray is used as the radiation source)
β: half width of peak (radian)
θ: reflection angle of spectrum Here, the half width β of the peak and the reflection angle θ of the spectrum are obtained by the following procedure.
(I) The peak with the highest intensity in the range of 2θ from 15 to 30° is defined as the (002) plane peak. The value of 2θ at the peak top of the (002) plane peak is defined as 2θ of the (002) plane peak, and the value obtained by dividing 2θ of the (002) plane peak by 2 is defined as the reflection angle θ of the spectrum.
(II) P ₁ (elevation side) and P ₂ (wide angle side) are the points that show half the intensity of the peak top of the (002) plane peak and are closest to 2θ on the small angle side and the wide angle side, respectively. , P ₁ and P ₂ are 2θ ₁ and 2θ ₂ . Then, the difference between 2θ ₁ and 2θ ₂ (2θ ₂ -2θ ₁ ) is defined as the peak half width β.
The X-ray diffraction spectrum of carbon particles may be measured by any known X-ray diffractometer. As a known X-ray diffractometer, for example, an X-ray diffractometer “SmartLab” manufactured by Rigaku Corporation can be cited.

Such carbon particles can be produced by highly controlling (i) maximum carbonization temperature, (ii) holding time.

The lower limit of the carbon element content ratio of the carbon particles contained in the sealing resin composition in the present embodiment is 80% or more, more preferably 82% or more, and still more preferably 85% or more. When the content ratio of the carbon element is equal to or higher than the above lower limit, the blackness of the carbon particles becomes more suitable, and the coloring power when kneaded into the resin composition becomes more favorable.
Moreover, the upper limit of the content ratio of the carbon element is 98% or less, preferably 97% or less, and more preferably 95% or less. When the content ratio of the carbon element is equal to or less than the above upper limit, the expression of conductivity of the carbon particles can be suppressed, and the electrical insulation when kneaded into the resin composition becomes better.

The carbon particles contained in the encapsulating resin composition in the present embodiment preferably have a value of b ^* defined by the CIE1976L ^* a ^* b ^* color system of −4 or more and +6 or less, and −3 or more. It is more preferably +5 or less, more preferably −2 or more and +4 or less, further preferably −2 or more and +3 or less, and further preferably −1 or more and +3 or less. When b ^* is within the above numerical range, the blackness of the carbon particles becomes more suitable, and the coloring power when kneaded into the resin composition becomes more favorable.

Carbon particles having b ^* values defined by the CIE1976L ^* a ^* b ^* color system within the above numerical range have (i) the maximum carbonization temperature, (ii) the retention time, and (iii) the particle diameter D of the carbon particles. ₅₀ can be manufactured by highly controlling.

The carbon particles contained in the encapsulating resin composition of the present embodiment have a particle diameter _D50 with a cumulative frequency of 50% in a volume-based cumulative frequency distribution curve measured using a laser diffraction particle size distribution analyzer. The lower limit is 0.1 μm or more, more preferably 0.2 μm or more, and even more preferably 0.3 μm or more. When the _D50 is equal to or higher than the lower limit, the blackness of the carbon particles becomes more suitable, and the dispersibility when kneaded into the resin composition is improved.
The upper limit of the particle diameter _D50 is 30 μm or less, preferably 20 μm or less, and even more preferably 15 μm or less. When the _D50 is equal to or less than the upper limit, the coloring power of the carbon particles becomes more suitable, and when the carbon particles are kneaded into the resin composition, the surface roughness of the resin composition is improved. can do.

The carbon particles contained in the encapsulating resin composition of the present embodiment have a particle diameter _D10 at which the cumulative frequency is 10% in a volume-based cumulative frequency distribution curve measured using a laser diffraction particle size distribution analyzer. It is preferably 0.01 μm to 15 μm, more preferably 0.02 μm to 10 μm, even more preferably 0.05 μm to 5 μm.
When _D10 is within the above numerical range, the blackness of the carbon particles becomes more suitable, and the dispersibility when kneaded into the resin composition is improved.

The carbon particles contained in the encapsulating resin composition of the present embodiment have a particle diameter _D90 at which the cumulative frequency is 90% in a volume-based cumulative frequency distribution curve measured using a laser diffraction particle size distribution analyzer. It is preferably 0.5 μm to 50 μm, more preferably 0.88 μm to 45 μm, even more preferably 1 μm to 40 μm.
When the _D90 is within the above numerical range, the coloring power of the carbon particles becomes more suitable, and when the carbon particles are kneaded into the resin composition, the surface roughness of the resin composition becomes better. be able to.

In the carbon particles contained in the encapsulating resin composition of the present embodiment, the cumulative frequencies in the volume-based cumulative frequency distribution curve measured using a laser diffraction particle size distribution analyzer are 10%, 50%, and 90%, respectively. Using the particle diameters D ₁₀ , D ₅₀ and D ₉₀ , the particle size distribution represented by the following formula (1) is preferably 0.5 to 2.0, more preferably 0.6 to 1.9 is more preferably 0.7 to 1.8.
Particle size distribution=(D ₉₀ −D ₁₀ )/D ₅₀ Equation (1)
When the particle size distribution is within the above numerical range, the blackness of the carbon particles becomes more suitable, the dispersibility when kneaded into the resin composition is improved, and the coloring power of the carbon particles is more suitable. Therefore, when the carbon particles are kneaded into the resin composition, the surface roughness of the resin composition can be improved.

The carbon particles contained in the encapsulating resin composition of the present embodiment preferably have an upper limit of sulfur content of 150 ppm or less, more preferably 100 ppm or less, and 50 ppm or less. is more preferred. Since the sulfur content is equal to or less than the upper limit, corrosion of electrical wiring inside the sealing structure can be suppressed when an electronic component is sealed with a sealing resin composition kneaded with carbon particles. For example, it is possible to highly suppress the corrosion of the joint between the Cu wire and the Al pad.
Although the lower limit of the sulfur content is not particularly limited, it is, for example, 0 ppm or more. Here, 0 ppm includes values below the detection limit of ion chromatography.
The sulfur content may be measured by a known method, for example, using a Dionex ICS2000 ion chromatograph, the sulfate ion in the measurement sample is quantified by the calibration curve method, and converted to the elemental content in the sample. can be measured as the sulfur content in the carbon particles.
Such carbon particles can be produced by not using a compound containing elemental sulfur such as sulfuric acid in the process of producing the raw material resin composition or the carbon particles, or by using only a small amount of such compound.

The upper limit of the chlorine content in the carbon particles contained in the sealing resin composition of the present embodiment is preferably 50 ppm or less, more preferably 40 ppm or less, and 30 ppm or less. is more preferred. By setting the chlorine content to be equal to or less than the upper limit, it is possible to suppress corrosion of electrical wiring inside the sealing structure when an electronic component is sealed with the sealing resin composition kneaded with carbon particles. For example, it is possible to highly suppress the corrosion of the joint between the Cu wire and the Al pad.
Although the lower limit of the chlorine content is not particularly limited, it is, for example, 0 ppm or more. Here, 0 ppm includes values below the lower limit of detection.
The chlorine content may be measured by a known method, for example, using a Dionex ICS2000 ion chromatograph, the chlorine ions in the measurement sample are quantified by the calibration curve method, and converted to the elemental content in the sample. can be measured as the chlorine content in the carbon particles.
Such carbon particles can be produced by not using compounds containing elemental chlorine such as hydrochloric acid, or by using only a small amount of such compounds in the raw material resin composition or the process of producing the carbon particles.

[Method for producing carbon particles]
The carbon particles contained in the encapsulating resin composition of the present embodiment can be produced by the following production method.

The carbon particles contained in the encapsulating resin composition of the present embodiment can be produced preferably by a production method including the following two steps.
That is, a carbonization step of carbonizing the raw material resin to obtain a carbide;
and a pulverizing step of pulverizing the carbide to obtain carbon particles.

(Carbonization process)
First, in the carbonization step, a carbonized product of the raw resin composition is obtained by carbonizing the raw resin composition. As a method for obtaining the carbide of the raw material resin composition, equipment capable of heat treatment under an inert gas atmosphere is preferably used. Known gases such as nitrogen, helium gas and argon gas can be used as the inert gas.

The maximum carbonization temperature in the carbonization step is preferably 400° C. to 800° C., more preferably 450° C. to 750° C., even more preferably 500° C. to 700° C., from the viewpoint of improving the specific resistance value of the carbon particles.

The time during which the maximum carbonization temperature is maintained in the carbonization step (hereinafter referred to as "holding time") is preferably 0 to 24 hours, more preferably 0, from the viewpoint of improving the specific resistance of the carbon particles. hours to 18 hours, more preferably 0 hours to 12 hours.

The carbon particles are selected from thermosetting resins, thermoplastic resins, and polymerizable high molecular weight materials (hereinafter sometimes simply referred to as "main component resins") as a raw material resin composition. It preferably contains carbides of the material.
Moreover, the shape of these raw material resin compositions may be, for example, a powder, a cured product, a liquid, or the like, but from the viewpoint of production efficiency, the liquid is preferred.
Although the raw material resin composition of the present invention may use only one type of resin as the main component resins, this is also referred to as the raw material resin composition for the sake of convenience.

Here, the thermosetting resin is not particularly limited, but for example, phenolic resins such as novolak-type phenolic resins and resol-type phenolic resins; epoxy resins such as bisphenol-type epoxy resins and novolak-type epoxy resins; aniline resins, melamine resins, Nitrogen-containing resins such as urea resins and cyanate resins; ketone resins; unsaturated polyester resins; urethane resins and furan resins. Alternatively, these may be modified products modified with various components.
The thermoplastic resin is not particularly limited, but examples include polyethylene, polystyrene, polyacrylonitrile, acrylonitrile-styrene (AS) resin, acrylonitrile-butadiene-styrene (ABS) resin, polypropylene, methacrylic resin, polyethylene terephthalate, polyamide, polycarbonate. , polyacetal, polyphenylene ether, polybutylene terephthalate, polyetheretherketone, polyetherimide, polyamideimide, polyimide, or polyphthalamide.
Other polymeric materials are not particularly limited, but include, for example, petroleum tar or pitch by-produced during ethylene production, coal tar produced during coal distillation, and heavy components or pitch obtained by distilling off low-boiling components of coal tar. , and petroleum-based or coal-based materials such as tar or pitch obtained by liquefying coal, crosslinked products of the above-mentioned petroleum-based or coal-based materials, and polymerizable high molecular weight materials such as spinning pitch. .
The main component resins may be used alone or in combination of two or more.

In the raw material resin composition, when a thermosetting resin is used as such main component resins, its curing agent can be used in combination.
Curing agents for thermosetting resins are not particularly limited, but for example, in the case of novolac type phenolic resins, hexamethylenetetramine; resol type phenolic resins; polyacetal; or paraform can be used. In the case of epoxy resins, polyamine compounds such as aliphatic polyamines and aromatic polyamines; acid anhydrides; imidazole compounds; dicyandiamide; novolac-type phenol resins; bisphenol-type phenol resins;
It should be noted that even a thermosetting resin that is usually used in combination with a curing agent can be used without a curing agent in the raw material resin composition of the present invention.

In addition to the main component resins, additives may be added to the raw material resin composition.
Although the additive is not particularly limited here, examples thereof include graphite and graphite modifiers, organic acids, inorganic acids, nitrogen-containing compounds, oxygen-containing compounds, aromatic compounds, and non-ferrous metal elements.
The above additives can be used alone or in combination of two or more depending on the type and properties of the main component resins used.

Equipment capable of heat treatment that can be used in the carbonization step of the present embodiment is not particularly limited, and known equipment can be selected. Known facilities include, for example, a batch-type electric furnace or a continuous furnace such as a rotary kiln or a roller hearth kiln.
The equipment may be used alone or in combination of two or more depending on the physical properties required for the carbon particles and the production efficiency of the carbon particles.

(Pulverization process)
Then, a pulverization step is performed. In the pulverization step, the carbide obtained in the carbonization step is pulverized to obtain carbon particles. At this time, from the viewpoint of improving the pulverization efficiency, preliminary pulverization for crushing the carbide in advance and main pulverization for crushing to the desired particle size of the carbon particles may be used in combination.

Regardless of whether it is pre-pulverization or main pulverization, the apparatus used in the pulverization step is not particularly limited, and any method may be used as long as it can pulverize the carbide. Devices used in the pulverization step include dry pulverizers such as rod mills, ball mills, bead mills, jet mills, cyclone mills, roller mills, pin mills and hammer mills; and known devices such as wet pulverizers such as high-pressure homogenizers and bead mills. can be used.
In the pulverization treatment, one or two or more of these devices may be used, or one type of device may be used for multiple pulverizations.

When a bead mill is used in the pulverization process, the material of the beads used is not particularly limited, regardless of whether it is dry or wet pulverization. Beads of material can be used. Among these, it is preferable to use zirconia beads from the viewpoint of metal contamination, abrasion resistance, and pulverization efficiency.

Moreover, the bead diameter may be selected according to the particle size and hardness of the carbide, and is, for example, 0.015 mm to 5 mm. Moreover, two or more kinds of beads having different particle diameters may be used in combination.

When wet pulverization is performed in the pulverization step, it is preferable to use water, an organic solvent, or a mixture thereof as a dispersion medium for dispersing the carbide to form a carbon material slurry. A known organic compound having a boiling point of 120° C. or lower can be used as the organic solvent. Examples thereof include alcohols such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol and 2-butanol, and ketones such as acetone, 2-butanone and 4-methyl-2-pentanone.

The concentration of the carbon material slurry during wet pulverization is preferably 1 wt % to 50 wt %, more preferably 1 wt % to 40 wt %, even more preferably 1 wt % to 30 wt %.
When the concentration of the carbon material slurry is equal to or less than the above upper limit, the fluidity of the carbon material slurry increases and the carbide can be more satisfactorily pulverized, which is preferable. Further, it is preferable that the concentration of the carbon material slurry is equal to or higher than the above lower limit because the efficiency of pulverizing the carbide is improved.

When two or more of the above equipments are used in combination, a sieving step may be included between equipment changes from the viewpoint of making the particle size of the carbon particles uniform and handling the carbon particles.

(Other processes)
When the pulverization step is performed by wet pulverization, a drying step of recovering carbon particles from the carbon material slurry by drying may be included after the pulverization step. Further, after the pulverization step, a secondary carbonization step of further heat-treating the carbon particles may be included for the purpose of further blackening the carbon particles.
Furthermore, after the pulverization step or the secondary carbonization step, sieving may be performed from the viewpoint of uniformizing the particle size of the carbon particles and improving the handling properties of the carbon particles.

[Thermosetting resin]
The encapsulating resin composition in this embodiment contains a thermosetting resin. Examples of the thermosetting resin include epoxy resins, polyimide resins, benzoxazine resins, unsaturated polyester resins, phenol resins, melamine resins, silicone resins, cyanate resins, maleimide resins, acrylic resins, phenol derivatives, and derivatives thereof. conventionally known thermosetting resins can be used.

Epoxy resins that can be used in the present embodiment include known epoxy resins that are generally used in encapsulating resin compositions. Examples of known epoxy resins include biphenyl type epoxy resins; bisphenol type epoxy resins such as bisphenol A type epoxy resins, bisphenol F type epoxy resins, tetramethylbisphenol F type epoxy resins; stilbene type epoxy resins; phenol novolak type epoxy resins. , cresol novolac type epoxy resins and other novolac type epoxy resins; triphenol methane type epoxy resins, alkyl-modified triphenol methane type epoxy resins and other trisphenol type epoxy resins exemplified by polyfunctional epoxy resins; phenol having a phenylene skeleton Phenol aralkyl epoxy resins such as aralkyl epoxy resins, naphthol aralkyl epoxy resins having a phenylene skeleton, phenol aralkyl epoxy resins having a biphenylene skeleton, and naphthol aralkyl epoxy resins having a biphenylene skeleton; dihydroxynaphthalene epoxy resins, dihydroxynaphthalene naphthol-type epoxy resins such as epoxy resins obtained by glycidyl-etherifying the dimer of; triazine nucleus-containing epoxy resins such as triglycidyl isocyanurate and monoallyl diglycidyl isocyanurate; Bridged cyclic hydrocarbon compound-modified phenol type epoxy resins can be mentioned. Among these, from the viewpoint of improving the bending strength of the encapsulating resin composition, novolac type epoxy resins, polyfunctional epoxy resins, phenol aralkyl type epoxy resins, naphthol type epoxy resins, triazine nucleus-containing epoxy resins, and bridged cyclic carbonization It preferably contains one or more epoxy resins selected from the group consisting of hydrogen compound-modified phenol-type epoxy resins.
As the epoxy resin, among the above specific examples, one or a combination of two or more thereof can be used.

Maleimide resins that can be used in the present embodiment include known maleimide resins that are generally used in encapsulating resin compositions. Known maleimide resins include 4,4′-diphenylmethanebismaleimide, m-phenylenebismaleimide, p-phenylenebismaleimide, 2,2-bis[4-(4-maleimidophenoxy)phenyl]propane, bis-(3 -ethyl-5-methyl-4-maleimidophenyl)methane, 4-methyl-1,3-phenylenebismaleimide, N,N'-ethylenedimaleimide, N,N'-hexamethylenedimaleimide, bis(4-maleimide phenyl) ether, bis(4-maleimidophenyl) sulfone, 3,3-dimethyl-5,5-diethyl-4,4-diphenylmethane bismaleimide, bisphenol A diphenyl ether bismaleimide, etc. Compounds having two maleimide groups in the molecule , polyphenylmethane maleimide, and the like, compounds having three or more maleimide groups in the molecule.
One of these may be used alone, or two or more may be used in combination.

The acrylic resin that can be used in the present embodiment is a compound having a radically polymerizable (meth)acryloyl group in the molecule, and the (meth)acryloyl group reacts to form a three-dimensional network structure and cure. It is a compound that can Although it is necessary to have one or more (meth)acryloyl groups in the molecule, two or more are preferably contained in order to form a three-dimensional network structure. Compounds having a radically polymerizable (meth)acryloyl group include, for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, ) acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 1,2-cyclohexanediol mono(meth)acrylate, 1,3-cyclohexanediol mono(meth)acrylate, 1,4-cyclohexane Diol mono (meth) acrylate, 1,2-cyclohexanedimethanol mono (meth) acrylate, 1,3-cyclohexanedimethanol mono (meth) acrylate, 1,4-cyclohexanedimethanol mono (meth) acrylate, 1,2- Cyclohexanediethanol mono(meth)acrylate, 1,3-cyclohexanediethanol mono(meth)acrylate, 1,4-cyclohexanediethanol mono(meth)acrylate, glycerin mono(meth)acrylate, glycerin di(meth)acrylate, trimethylolpropane mono (meth) acrylate, trimethylolpropane di (meth) acrylate, pentaerythritol mono (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, neopentyl glycol mono (meth) acrylate, etc. and (meth)acrylates having a carboxyl group obtained by reacting a (meth)acrylate having a hydroxyl group with a dicarboxylic acid or a derivative thereof. Dicarboxylic acids which can be used here include, for example, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, maleic acid, fumaric acid, phthalic acid, tetrahydrophthalic acid. , hexahydrophthalic acid and derivatives thereof.

In the present embodiment, the content of all thermosetting resins in the encapsulating resin composition is determined from the viewpoint of maintaining various physical properties including the curability of conventional encapsulating resin compositions. It is preferably 5% by mass or more, more preferably 6% by mass or more, and still more preferably 7% by mass or more based on the total solid content of the product.
In addition, from the viewpoint of improving the high temperature reliability and bending strength of the cured product obtained using the encapsulating resin composition, the content of the thermosetting resin in the encapsulating resin composition is It is preferably 15% by mass or less, more preferably 14% by mass or less, and still more preferably 13% by mass or less based on the total solid content of the composition.

In the present embodiment, the sealing resin composition preferably does not contain ionic impurities such as Na ions, Cl ions, and S ions as much as possible from the viewpoint of high-temperature reliability.

[Curing agent]
The encapsulating resin composition in this embodiment contains a curing agent. Curing agents used in the encapsulating resin composition of the present embodiment can be broadly classified into three types, for example, polyaddition curing agents, catalyst curing agents, and condensation curing agents. These may be used alone or in combination of two or more.

Polyaddition type curing agents include, for example, aliphatic polyamines such as diethylenetriamine (DETA), triethylenetetramine (TETA), metaxylylenediamine (MXDA), diaminodiphenylmethane (DDM), m-phenylenediamine (MPDA), In addition to aromatic polyamines such as diaminodiphenylsulfone (DDS), polyamine compounds including dicyandiamide (DICY), organic acid dihydrazide, etc.; alicyclic acids such as hexahydrophthalic anhydride (HHPA) and methyltetrahydrophthalic anhydride (MTHPA) Acid anhydrides including aromatic acid anhydrides such as anhydrides, trimellitic anhydride (TMA), pyromellitic anhydride (PMDA), and benzophenonetetracarboxylic acid (BTDA); novolak-type phenolic resins, polyvinylphenol, aralkyl-type 1 selected from the group consisting of phenolic resin-based curing agents such as phenolic resins; polymercaptan compounds such as polysulfides, thioesters and thioethers; isocyanate compounds such as isocyanate prepolymers and blocked isocyanates; organic acids such as carboxylic acid-containing polyester resins including one or more species.

Catalytic curing agents include, for example, benzyldimethylamine (BDMA), tertiary amine compounds such as 2,4,6-trisdimethylaminomethylphenol (DMP-30); 2-methylimidazole, 2-ethyl-4- imidazole compounds such as methylimidazole (EMI24); Lewis acids such as _BF3 complexes.

Condensation-type curing agents include, for example, one or more selected from the group consisting of resol-type phenol resins; urea resins such as methylol group-containing urea resins; and melamine resins such as methylol group-containing melamine resins.

Among these, from the viewpoint of improving the balance of flame resistance, moisture resistance, electrical properties, curability, storage stability, etc. of the obtained encapsulating resin composition, it is more preferable to contain a phenolic resin-based curing agent. . As the phenolic resin-based curing agent, for example, monomers, oligomers, and polymers in general having two or more phenolic hydroxyl groups in one molecule can be used, and the molecular weight and molecular structure are not limited.

Phenolic resin-based curing agents include, for example, novolac type phenolic resins such as phenol novolac resin, cresol novolac resin, and bisphenol novolac; polyfunctional phenolic resins such as polyvinylphenol and triphenylmethane type phenolic resin; Modified phenol resins such as pentadiene-modified phenol resins; phenol aralkyl resins having a phenylene skeleton and/or biphenylene skeleton; phenol aralkyl-type phenol resins such as naphthol aralkyl resins having a phenylene and/or biphenylene skeleton; It contains one or more selected from the group consisting of compounds. Among these, from the viewpoint of suppressing the warp of the molded body, it is more preferable to contain a novolac-type phenolic resin, a polyfunctional-type phenolic resin, and a phenol-aralkyl-type phenolic resin. Phenol novolak resins, phenol aralkyl resins having a biphenylene skeleton, and triphenylmethane type phenol resins can also be preferably used.

The lower limit of the blending ratio of the curing agent is preferably 2% by mass or more, more preferably 3% by mass or more, relative to the total solid content of the encapsulating resin composition. When the lower limit of the blending ratio is within the above range, sufficient fluidity can be obtained. The upper limit of the mixing ratio of the curing agent is preferably 16% by mass or less, more preferably 15% by mass or less, relative to the entire encapsulating resin composition. Mutual adhesion can be appropriately suppressed when the upper limit of the mixing ratio is within the above range. Moreover, in order to improve fluidity and meltability, it is desirable to appropriately adjust the mixing ratio according to the type of curing agent used.

[Inorganic filler]
The encapsulating resin composition in this embodiment contains an inorganic filler. The inorganic filler has the function of reducing the increase in moisture absorption and the decrease in strength associated with curing of the encapsulating resin composition. can.

Examples of inorganic fillers include fused silica, spherical silica, fused spherical silica, crystalline silica, alumina, silicon nitride and aluminum nitride. These inorganic fillers may be used alone or in combination. .

The average particle diameter _D50 of the inorganic filler can be, for example, 0.01 μm or more and 150 μm or less.

The lower limit of the amount of the inorganic filler in the encapsulating resin composition is preferably 60% by mass or more, more preferably 70% by mass or more, relative to the total mass of the encapsulating resin composition, More preferably, it is 80% by mass or more. When the lower limit is within the above range, it is possible to more effectively reduce the increase in moisture absorption and the decrease in strength accompanying curing of the resulting encapsulating resin composition. properties can be further improved.

The upper limit of the amount of the inorganic filler in the encapsulating resin composition is preferably 93% by mass or less, more preferably 91% by mass or less, relative to the total mass of the encapsulating resin composition. Yes, more preferably 90% by mass or less. When the upper limit is within the above range, the obtained encapsulating resin composition has good fluidity and good moldability.

(other ingredients)
The encapsulating resin composition in the present embodiment may contain the following components in addition to the coloring agent, thermosetting resin, curing agent and inorganic filler.

(Curing accelerator)
The curing accelerator has a function of promoting the reaction between the reactive group of the thermosetting resin and the reactive group of the curing agent, and curing accelerators commonly used in the field are used.

Specific examples of curing accelerators include tetrasubstituted phosphonium compounds such as tetraphenylphosphonium 4,4'-sulfonyldiphenolate, tetraphenylphosphonium bis(naphthalene-2,3-dioxy)phenylsilicate, organic phosphines, and phosphobetaines. compounds, adducts of phosphine compounds and quinone compounds, and adducts of phosphonium compounds and silane compounds; Nitrogen atom-containing compounds such as amidines and tertiary amines exemplified by methylimidazole and the like, and quaternary salts of the above amidines and amines, may be used alone or in combination of two or more thereof. . Among these, phosphorus atom-containing compounds are preferred from the viewpoint of curability, and phosphobetaine compounds and adducts of phosphine compounds and quinone compounds are particularly preferred from the viewpoint of solder resistance and fluidity. Phosphorus atom-containing compounds such as tetra-substituted phosphonium compounds and adducts of phosphonium compounds and silane compounds are particularly preferred in that they cause only mild contamination.

Examples of organic phosphines that can be used in the encapsulating resin composition include primary phosphines such as ethylphosphine and phenylphosphine; secondary phosphines such as dimethylphosphine and diphenylphosphine; tertiary phosphines such as phosphines; and derivatives thereof.

(coupling agent)
The coupling agent has the function of improving the adhesion between the thermosetting resin and the inorganic filler when the inorganic filler is contained in the sealing resin composition. For example, a silane coupling agent etc. are used.

Various silane coupling agents can be used, but aminosilane is preferably used. Thereby, the fluidity|liquidity and solder resistance of the resin composition for sealing can be improved.

Examples of aminosilane include, but are not limited to, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-β (aminoethyl)γ-aminopropyltrimethoxysilane, N-β (aminoethyl)γ -aminopropylmethyldimethoxysilane, N-phenyl γ-aminopropyltriethoxysilane, N-phenyl γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropyltriethoxysilane, N-6-(amino hexyl)3-aminopropyltrimethoxysilane, N-(3-(trimethoxysilylpropyl)-1,3-benzenedimethanamine, and the like.

The lower limit of the mixing ratio of the coupling agent such as the silane coupling agent is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and particularly preferably 0.01% by mass or more in the total encapsulating resin composition. It is 1% by mass or more. If the lower limit of the mixing ratio of the coupling agent such as the silane coupling agent is within the above range, the interface strength between the thermosetting resin and the inorganic filler does not decrease, and good solder crack resistance in electronic devices is obtained. You can get sex. The upper limit of the mixing ratio of the coupling agent such as the silane coupling agent is preferably 1% by mass or less, more preferably 0.8% by mass or less, and particularly preferably 0.8% by mass or less in the entire encapsulating resin composition. It is 6% by mass or less. If the upper limit of the mixing ratio of the coupling agent such as the silane coupling agent is within the above range, the interfacial strength between the thermosetting resin and the inorganic filler does not decrease, and good solder crack resistance in the device is obtained. can be obtained. Further, when the mixing ratio of the coupling agent such as the silane coupling agent is within the above range, the water absorption of the cured product of the encapsulating resin composition does not increase, and good solder crack resistance in the electronic device is obtained. can be obtained.

(Flame retardants)
The flame retardant has a function of improving the flame retardancy of the encapsulating resin composition, and generally used flame retardants are used.

Specifically, metal hydroxides that inhibit the combustion reaction by dehydrating and absorbing heat during combustion, and composite metal hydroxides that can shorten the combustion time are preferably used.

Examples of metal hydroxides include aluminum hydroxide, magnesium hydroxide, calcium hydroxide, barium hydroxide, and zirconia hydroxide.

The composite metal hydroxide is a hydrotalcite compound containing two or more metal elements, wherein at least one metal element is magnesium, and the other metal elements are calcium, aluminum, tin, titanium, and iron. , cobalt, nickel, copper, or zinc. As such a composite metal hydroxide, a magnesium hydroxide-zinc solid solution is commercially available and readily available.

Among them, aluminum hydroxide and magnesium hydroxide/zinc solid solution are preferable from the viewpoint of the balance between adhesion and high-temperature reliability.

The flame retardants may be used alone or in combination of two or more. Further, for the purpose of reducing the influence on adhesion, the surface may be treated with a silicon compound such as a silane coupling agent or an aliphatic compound such as wax before use.

In addition to the above-described other components, ion scavengers; natural waxes such as carnauba wax, synthetic waxes such as polyethylene wax, higher fatty acids such as stearic acid and zinc stearate, metal salts thereof, and release agents such as paraffin; A low-stress agent such as silicone oil, silicone rubber, acrylonitrile-butadiene rubber, dimethylsiloxane-alkylcarboxylic acid-4,4'-(1-methylethylidene)bisphenol glycidyl ether copolymer may be blended as appropriate.

The encapsulating resin composition of the present embodiment is prepared by mixing the coloring agent, the thermosetting resin, the curing agent, the inorganic filler and, if necessary, the other components by a method commonly used in the art. can be obtained by

The encapsulating resin composition in this embodiment uses a mold for spiral flow measurement according to EMMI-1-66, and the lower limit of the flow length measured under the conditions of a mold temperature of 175 ° C. and a measurement time of 5 minutes. is preferably 50 cm or more, more preferably 75 cm or more, and even more preferably 100 cm or more. When the flow length is at least the above lower limit, the encapsulating moldability of the encapsulating resin composition becomes more suitable.
Also, the upper limit of the flow length is preferably 300 cm or less, more preferably 275 cm or less, and even more preferably 250 cm or less. When the flow length is equal to or less than the above upper limit, the curability of the encapsulating resin composition and cured product properties such as burr generation during molding and high-temperature reliability become more favorable.

The encapsulating resin composition in this embodiment is a cured product obtained by curing the encapsulating resin composition by heat treatment at 175° C. for 30 minutes, and is defined by CIE1976L ^* a ^* b ^* color system. Using L ^* , a ^* , b ^* , the following equation (1):
D=[(L ^* −27) ² +(a ^* −(−1)) ² +(b ^* −(−3)) ² ] ^1/2 (1)
The upper limit of the D value defined by is preferably 3.2 or less, more preferably 2.8 or less, further preferably 2.7 or less, and 2.5 or less is more preferably 2.3 or less, more preferably 2.1 or less, even more preferably 1.8 or less, and even more preferably 1.6 or less. When the D value is equal to or less than the above upper limit, when the encapsulating resin composition of the present embodiment is used as a cured product, the degree of coloring is improved and the laser mark property is more suitable.
Although the lower limit of the D value is not particularly limited, it is, for example, 0 or more.

The encapsulating resin composition in the present embodiment _is obtained by curing the encapsulating resin composition by heat treatment at 175 ° C. for 30 minutes. The lower limit of the ratio ε ₁ /ε ₁₀ to ε ₁₀ is preferably 0.9 or more, more preferably 0.95 or more, and even more preferably 1.0 or more. When the ratio ε ₁ /ε ₁₀ is equal to or higher than the above lower limit, the room-temperature storage stability and encapsulation moldability of the encapsulating resin composition become more suitable.
Also, the upper limit of the ratio ε ₁ /ε ₁₀ is preferably 1.2 or less, more preferably 1.15 or less, and even more preferably 1.1 or less. When the ratio ε ₁ /ε ₁₀ is equal to or less than the above upper limit, the curability of the encapsulating resin composition and cured product properties such as solder crack resistance and high-temperature reliability become more suitable.

The encapsulating resin composition in the present embodiment is a cured product obtained by curing the encapsulating resin composition by heat treatment at 175 ° C. for 30 minutes _. The lower limit of the ratio δ ₁ /δ ₁₀ to δ ₁₀ is preferably 0.8 or more, more preferably 0.85 or more, and even more preferably 0.9 or more. When the ratio δ ₁ /δ ₁₀ is equal to or higher than the above lower limit, the room-temperature storage stability and encapsulation moldability of the encapsulating resin composition become more suitable.
Also, the upper limit of the ratio δ ₁ /δ ₁₀ is preferably 1.1 or less, more preferably 1.05 or less, and even more preferably 1.0 or less. When the ratio δ ₁ /δ ₁₀ is equal to or less than the above upper limit value, the curability of the encapsulating resin composition and cured product properties such as solder crack resistance and high-temperature reliability become more suitable.

<Electronic Device>
In one embodiment of the present invention, an electronic device in which a semiconductor element is encapsulated with a cured product of the encapsulating resin composition of the present embodiment can be provided.

Although the embodiments of the present invention have been described above, these are examples of the present invention, and various configurations other than those described above can be adopted. Moreover, the present invention is not limited to the above-described embodiments, and includes modifications, improvements, etc. within the scope of achieving the object of the present invention.

Embodiments of the present invention will be described in detail based on examples and comparative examples. It should be noted that the invention is not limited to the examples only.

<Examples, Comparative Examples>
(Preparation of encapsulating resin composition)
For each example and each comparative example, a sealing resin composition was prepared as follows.
First, each component shown in Table 1 was mixed with a mixer. Next, the obtained mixture was roll-kneaded, cooled and pulverized to obtain a sealing resin composition in the form of granules.
Details of each component in Table 1 are as follows. In addition, the blending ratio of each component shown in Table 1 indicates the blending ratio (% by weight) with respect to the entire encapsulating resin composition.
(material)
(Inorganic filler)
Inorganic filler 1: fused silica (MSV-SF540, Tatsumori Co., Ltd., particle diameter _D50 : 13 μm)
Inorganic filler 2: Fused spherical silica (FB-100XFD, manufactured by Denka, particle diameter _D50 : 14 μm)
Inorganic filler 3: fused silica (manufactured by Admatechs, SD2500-SQ, particle diameter _D50 : 0.9 μm)
Inorganic filler 4: fused silica (manufactured by Admatechs, SD5500-SQ, particle diameter _D50 : 1.5 μm)

(colorant)
Colorant 1: Carbon particles 1 prepared by the following (Method 1) (particle diameter _D50 : 1.27 μm, _D10 : 0.66 μm, _D90 : 2.56 μm, specific resistance: 4.1×10 ¹⁰ Ω cm, sulfur content: 10 ppm (lower limit of measurement) or less, chlorine content: 25 ppm (lower limit of measurement) or less, Lc: 8 Å)
(Method 1)
A carbide was obtained by carbonizing a phenol resin (manufactured by Sumitomo Bakelite Co., Ltd.: PR-51464) at 580° C. for 160 minutes in a nitrogen atmosphere. The resulting carbide was pulverized with a cyclone mill and sieved using an ultrasonic vibrating sieve (mesh size: 20 μm) to obtain a pre-pulverized material having a particle diameter D ₅₀ of 10 μm. Next, the above preliminary pulverized product was finely pulverized using a dry bead mill using Φ12.5 mm zirconia beads to obtain carbon particles. Finally, the carbon particles were sieved with a hand sieve (opening: 212 μm) to remove agglomerates, and carbon particles 1 were obtained.

Colorant 2: Carbon particles 2 (particle diameter _D50 : 0.95 μm, _D10 : 0.56 μm, _D90 : 1.89 μm, specific resistance: 9.5×10 ⁸ Ω cm, sulfur content: 10 ppm (lower limit of measurement) or less, chlorine content: 25 ppm (lower limit of measurement) or less, Lc: 9 Å)
(Method 2)
A phenol resin (manufactured by Sumitomo Bakelite Co., Ltd.: PR-51464) was carbonized in a nitrogen atmosphere at 580° C. for 260 minutes to obtain a carbide. The resulting carbide was pulverized with a cyclone mill and sieved using an ultrasonic vibrating sieve (mesh size: 20 μm) to obtain a pre-pulverized material having a particle diameter D ₅₀ of 10 μm. Next, the pre-pulverized product was finely pulverized using a dry bead mill using Φ1.0 mm zirconia beads to obtain carbon particles. Finally, the carbon particles were sieved with a hand sieve (opening: 212 μm) to remove agglomerates, and carbon particles 2 were obtained.

Colorant 3: Carbon particles 3 (particle diameter _D50 : 1.36 μm, _D10 : 0.73 μm, _D90 : 2.64 μm, specific resistance: 3.1×10 ⁶ Ω cm, sulfur content: 10 ppm (lower limit of measurement) or less, chlorine content: 25 ppm (lower limit of measurement) or less, Lc: 8 Å)
(Method 3)
A carbide was obtained by carbonizing a phenol resin (manufactured by Sumitomo Bakelite Co., Ltd.: PR-51464) at 580° C. for 160 minutes in a nitrogen atmosphere. The resulting carbide was pulverized with a cyclone mill and sieved using an ultrasonic vibrating sieve (mesh size: 20 μm) to obtain a pre-pulverized material having a particle diameter D ₅₀ of 10 μm. Next, the above preliminary pulverized product was finely pulverized using a dry bead mill using Φ12.5 mm zirconia beads to obtain carbon particles. Thereafter, the carbon particles were further heat-treated at 630° C. for 45 minutes to obtain secondary carbides. Finally, the secondary carbide was sieved with a hand sieve (mesh size: 212 μm) to remove agglomerates, and carbon particles 3 were obtained.

Colorant 4: Carbon particles 4 (particle diameter _D50 : 0.46 μm, _D10 : 0.30 μm, _D90 : 0.73 μm, specific resistance: 8.0×10 ⁴ Ω cm, sulfur content: 10 ppm (lower limit of measurement) or less, chlorine content: 25 ppm (lower limit of measurement) or less, Lc: 10 Å)
(Method 4)
A carbide was obtained by carbonizing a phenol resin (manufactured by Sumitomo Bakelite Co., Ltd.: PR-51464) at 580° C. for 160 minutes in a nitrogen atmosphere. The resulting carbide was pulverized with a cyclone mill and sieved using an ultrasonic vibrating sieve (mesh size: 20 μm) to obtain a pre-pulverized material having a particle diameter D ₅₀ of 10 μm. Next, 15 parts by weight of the pre-pulverized product was dispersed in 85 parts by weight of water, and finely pulverized using a wet bead mill using Φ0.3 mm zirconia beads to obtain a carbon material slurry. Thereafter, the carbon material slurry was pre-dried at 100° C. for 18 hours and then dried at 200° C. for 6 hours to obtain carbon particles. The carbon particles were further heat-treated at 630° C. for 45 minutes to obtain secondary carbides. Finally, carbon particles 4 were obtained by sieving the secondary carbide with a hand sieve (opening: 212 μm) to remove aggregates.

Colorant 5: Carbon particles 5 (particle diameter _D50 : 2.34 μm, _D10 : 1.06 μm, _D90 : 4.39 μm, specific resistance: 5.7×10 ⁷ Ω cm, sulfur content: 10 ppm (lower limit of measurement) or less, chlorine content: 25 ppm (lower limit of measurement) or less, Lc: 13 Å)
(Method 5)
A phenol resin (manufactured by Sumitomo Bakelite Co., Ltd.: PR-51464) was carbonized in a nitrogen atmosphere at 635° C. for 30 minutes to obtain a carbide. The resulting carbide was pulverized with a cyclone mill and sieved using an ultrasonic vibrating sieve (mesh size: 20 μm) to obtain a pre-pulverized material having a particle diameter D ₅₀ of 10 μm. Next, carbon particles were obtained by finely pulverizing the pre-pulverized product using a dry bead mill using Φ1.5 mm zirconia beads. Thereafter, carbon particles 5 were obtained by sieving the carbide with a hand sieve (opening: 212 μm) to remove aggregates.

Colorant 6: Carbon black (manufactured by Mitsubishi Chemical Corporation, MA600, particle diameter _D50 : 10 μm, _D10 : 1 μm, _D90 : 16 μm, specific resistance value: 1.0 × 10 ^-1 Ω cm, sulfur content: 10 ppm (lower limit of measurement) or less, chlorine content: 25 ppm (lower limit of measurement) or less, Lc: 31 Å)
Colorant 7: Black titanium oxide (TilackD TM-HPD, manufactured by Ako Kasei Co., Ltd., particle diameter _D50 : 0.70 μm, _D10 : 0.35 μm, _D90 : 1.4 μm, specific resistance: 1.0 × 10 ^4Ω cm)

Colorant 8: Carbon particles 8 (particle diameter _D50 : 2.3 μm, _D10 : 0.98 μm, _D90 : 4.38 μm, specific resistance: 7.0×10 ³ Ω cm, sulfur content: 10 ppm (lower limit of measurement) or less, chlorine content: 25 ppm (lower limit of measurement) or less, Lc: 12 Å)
(Method 8)
A phenol resin (manufactured by Sumitomo Bakelite Co., Ltd.: PR-51464) was carbonized in a nitrogen atmosphere at 705° C. for 30 minutes to obtain a carbide. The resulting carbide was pulverized with a cyclone mill and sieved using an ultrasonic vibrating sieve (mesh size: 20 μm) to obtain a pre-pulverized material having a particle diameter D ₅₀ of 10 μm. Next, carbon particles were obtained by finely pulverizing the pre-pulverized product using a dry bead mill using Φ1.5 mm zirconia beads. Thereafter, carbon particles 8 were obtained by sieving the carbide with a hand sieve (opening: 212 μm) to remove aggregates.

Colorant 9: Carbon particles 9 (particle diameter _D50 : 2.37 μm, _D10 : 1.05 μm, _D90 : 4.37 μm, specific resistance: 1.1×10 ² Ω cm, sulfur content: 10 ppm (lower limit of measurement) or less, chlorine content: 25 ppm (lower limit of measurement) or less, Lc: 12 Å)
(Method 9)
A phenol resin (PR-51464 manufactured by Sumitomo Bakelite Co., Ltd.) was carbonized in a nitrogen atmosphere at 715° C. for 30 minutes to obtain a carbide. The resulting carbide was pulverized with a cyclone mill and sieved using an ultrasonic vibrating sieve (mesh size: 20 μm) to obtain a pre-pulverized material having a particle diameter D ₅₀ of 10 μm. Next, carbon particles were obtained by finely pulverizing the pre-pulverized product using a dry bead mill using Φ1.5 mm zirconia beads. Thereafter, carbon particles 9 were obtained by sieving the carbide with a hand sieve (opening: 212 μm) to remove aggregates.

The particle diameters _D50 , _D10 and _D90 of each carbon particle were measured by the following methods.
0.05 g of each carbon particle was added to a mixture of 1 cc of a 100-fold diluted solution by weight of polyoxyethylene sorbitan monolaurate (manufactured by Kishida Chemical Co., Ltd., Tween 20) and 5 cc of water, and ultrasonically dispersed to prepare a measurement sample. . Using the above measurement sample, in the volume-based cumulative frequency distribution curve measured using a laser diffraction particle size distribution analyzer (manufactured by Horiba, Ltd., LA-920), the particle diameter D when the cumulative frequency is 50% ₅₀ , the particle diameter _D10 at a cumulative frequency of 10% and the particle diameter _D90 at a cumulative frequency of 90% were measured.

The specific resistance value of each carbon particle was measured by the following method.
1 g of each carbon particle was set in a powder resistance measurement system resistance meter (Hiresta UX/Loresta GP, MCP-PD51 type, manufactured by Nitto Seiko Analyticc Co., Ltd. (former company name: Mitsubishi Chemical Analyticc Co., Ltd.)), and a 20 kN load was applied. The actual specific resistance was measured.

The sulfur content and chlorine content in each carbon particle were measured by the following methods.
10 mg of each carbon particle was completely burned in an oxygen-substituted closed flask. The gas generated at this time was collected in an alkaline hydrogen peroxide absorbent previously added to the flask, and then adjusted to 50 ml to obtain a measurement sample. Using a Dionex ICS2000 ion chromatograph, the sulfate ions and chloride ions in the measurement sample are quantified by the calibration curve method, converted to the element content in the sample, and the sulfur content and chlorine content in the carbon particles. bottom.

The crystallite size Lc of each carbon particle was measured by the following method.
For each carbon particle, powder X-ray diffraction measurement was performed using an X-ray diffractometer "SmartLab" manufactured by Rigaku Co., Ltd., using CuKα rays as a radiation source. A diffraction spectrum was obtained. The powder X-ray diffraction measurement was carried out by setting a sample holder filled with carbon particles on the observation table of the X-ray diffractometer, setting the scanning axis to 2θ/θ, sampling width of 0.01°, and scanning speed of 2°/min. gone. From the obtained X-ray diffraction spectrum, a straight line selected according to <Method> below was removed as a background.

<Method>
(1) In the above X-ray diffraction spectrum with 2θ on the horizontal axis and diffraction intensity on the vertical axis, one of the points at 2θ = 10° or 2θ = 15° and the point at 2θ = 30° or 2θ = Select any one of the 35° points and connect the two selected points with a straight line to create a total of four straight lines.
(2) Select one of the four straight lines created in (1) above.
(3) In the region where 2θ is 10° or more and 35° or less, find the area S surrounded by the straight line selected in (2) above and the X-ray diffraction spectrum located below the straight line.
(4) The steps (2) and (3) are repeated for each of the four straight lines created in (1) above, and the straight line L that minimizes the obtained area S is specified.
(5) Let the straight line L be the background straight line.

Next, the peak with the highest intensity in the range of 2θ from 15 to 30° was defined as the (002) plane peak. The value of 2θ at the peak top of the (002) plane peak was defined as 2θ of the (002) plane peak, and the value obtained by dividing 2θ of the (002) plane peak by 2 was defined as the reflection angle θ of the spectrum.
Furthermore, the points showing half the intensity of the peak top of the (002) plane peak and closest to 2θ on the small-angle side and the wide-angle side are P ₁ (elevated side) and P ₂ (wide-angle side), respectively, The values of 2θ at _P1 and _P2 were taken as _2θ1 and _2θ2 . Then, the difference between 2θ ₁ and 2θ ₂ (2θ ₂ -2θ ₁ ) was defined as the peak half width β.
Then, from the obtained half width β of the (002) plane peak and the reflection angle θ of the spectrum, the crystallite size Lc was determined using the following Scherrer's equation.
Lc=0.94λ/(β cos θ) (Scherrer's formula)
Lc: crystallite size λ: 0.15418 nm
β: half width of peak (radian)
θ: Spectral reflection angle

(Silane coupling agent)
Silane coupling agent 1: phenylaminopropyltrimethoxysilane (CF4083, Dow Corning Toray Co., Ltd.)

(Thermosetting resin)
Thermosetting resin 1: Biphenylene skeleton-containing phenol aralkyl type epoxy resin (manufactured by Nippon Kayaku Co., Ltd., NC3000)
Thermosetting resin 2: polyfunctional epoxy resin (YL6677, manufactured by Mitsubishi Chemical Corporation)

(curing agent)
Curing agent 1: p-biphenylene-modified phenolic resin (MEH-7851SS, manufactured by Meiwa Kasei Co., Ltd.)
Curing agent 2: Triphenylmethane type phenolic resin (HE910-20, manufactured by Air Water)

(Flame retardants)
Flame retardant 1: aluminum hydroxide (BE043LA, manufactured by Nippon Light Metal Co., Ltd.)

(Release agent)
Release agent 1: Stearic acid with a carboxyl group (SR-Sakura, manufactured by NOF Corporation)

(Ion scavenger)
Ion scavenger 1: magnesium aluminum hydroxide carbonate hydrate (manufactured by Kyowa Chemical Industry Co., Ltd., DHT-4H)

(Curing accelerator)
Curing accelerator 1: tetraphenylphosphonium 4,4'-sulfonyl diphenolate represented by the following chemical formula

Curing accelerator 2: Curing accelerator represented by the following formula (tetraphenylphosphonium bis(naphthalene-2,3-dioxy)phenyl silicate)

(Low stress agent)
Low stress agent: dimethylsiloxane-alkylcarboxylic acid-4,4'-(1-methylethylidene) bisphenol glycidyl ether copolymer (manufactured by Sumitomo Bakelite Co., Ltd., M69B)

(Evaluation of the physical properties)
Each physical property of the encapsulating resin composition obtained in each example was evaluated by the following methods.

(spiral flow (SF), gel time)
Using a low-pressure transfer molding machine ("KTS-15" manufactured by Kotaki Seiki Co., Ltd.), a mold for spiral flow measurement according to EMMI-1-66 was placed at 175 ° C., measurement time 5 minutes, injection pressure 6.9 MPa. , under the conditions of a pressure holding time of 120 seconds, the encapsulating resin composition of each example and each comparative example was injected, the flow length was measured, and this was defined as a spiral flow. In addition, the gel time was measured from the start of injection until the sealing resin composition cured and stopped flowing.
The spiral flow is a fluidity parameter, and the larger the value, the better the fluidity.

(linear expansion coefficient)
The coefficient of linear expansion of the resulting encapsulating resin composition was measured for each example and each comparative example. The measurement was performed using a low-pressure transfer molding machine (“KTS-30” manufactured by Kotaki Seiki Co., Ltd.) at a mold temperature of 175 ° C., an injection pressure of 9.8 MPa, and a curing time of 120 seconds. A molded article was obtained. Then, the obtained molded article was post-cured at 175° C. for 4 hours to prepare a test piece. Then, for the obtained test piece, using a thermomechanical analyzer (manufactured by Seiko Instruments Inc., TMA100), under the conditions of a measurement temperature range of 0 ° C. to 400 ° C. and a heating rate of 5 ° C./min, The average linear expansion coefficient CTE1 (ppm/°C) at 25-70°C and the average linear expansion coefficient CTE2 (ppm/°C) at 270-290°C were measured.

(Glass transition temperature (Tg), TMA)
The glass transition temperature of the encapsulating resin composition of each example and each comparative example was measured according to JIS K 6911. That is, the encapsulating resin composition of each example and each comparative example was tested using a transfer molding machine at a mold temperature of 175 ° C., an injection pressure of 6.9 MPa, and a curing time of 90 seconds. A piece was molded, post-cured at 175° C. for 2 hours, and a thermomechanical analyzer (manufactured by Seiko Instruments Inc., TMA/SS6000) was used to obtain the coefficient of thermal expansion of the test piece at a heating rate of 5° C./min. was measured. Next, based on the obtained measurement results, the glass transition temperature (Tg) of the cured product was calculated from the inflection point of the coefficient of thermal expansion.

(flexural modulus, bending strength)
For each example and each comparative example, using a low-pressure transfer molding machine (KTS-30 manufactured by Kotaki Seiki Co., Ltd.), sealing was performed under the conditions of a mold temperature of 175 ° C., an injection pressure of 9.8 MPa, and a curing time of 120 seconds. A molded article having a length of 80 mm, a width of 10 mm and a thickness of 4 mm was obtained. The obtained molding was subjected to heat treatment at 200° C. for 4 hours as a post-curing, and a test piece was used. .

(water absorption rate)
For each example and each comparative example, using a low-pressure transfer molding machine (KTS-30 manufactured by Kotaki Seiki Co., Ltd.), sealing was performed under the conditions of a mold temperature of 175 ° C., an injection pressure of 7.4 MP, and a curing time of 120 seconds. A test piece having a diameter of 50 mm and a thickness of 3 mm was prepared by injection molding of the resin composition, and cured at 200° C. for 4 hours. After that, the obtained test piece was subjected to humidification treatment in a boiling environment for 24 hours, and the weight change before and after the humidification treatment was measured to obtain the water absorption rate.

(Adhesion)
For each example and each comparative example, using a low-pressure transfer molding machine (KTS-30, manufactured by Kotaki Seiki Co., Ltd.), the sealing resin was molded under the conditions of a mold temperature of 175 ° C., an injection pressure of 10 MPa, and a curing time of 180 seconds. The composition was injection-molded to form 10 adhesion strength test specimens of 3.6 mmφ×3 mm on 9×29 mm strip-shaped test silicon plates.
After that, for the sample cured under the conditions of 175 ° C. for 3 hours, measure the die shear strength at room temperature (25 ° C.) or 260 ° C. using an automatic die shear measurement device (DAGE4000 manufactured by Nordson Advanced Technologies). , the adhesion (MPa) was obtained.

(Color, D value)
For each example and each comparative example, using a low-pressure transfer molding machine (KTS-30, manufactured by Kotaki Seiki Co., Ltd.), the above sealing was performed under the conditions of a mold temperature of 175 ° C., an injection pressure of 9.8 MPa, and a curing time of 300 seconds. A hardened product of the sealing resin composition having a diameter of 50 mm and a thickness of 3 mm was obtained by transfer molding the sealing resin composition.
Next, the L ^* value, a* value, and ^{b* value} of the obtained cured product were measured using a Color Reader CR-13 manufactured by Konica Minolta Sensing Co., Ltd. (measurement mode: transmission, number of measurements: n=3). Conversion to numerical values in the CIE1976L ^* a ^* b ^* color system was performed by the main body of the apparatus to obtain data in the CIE1976L ^* a ^* b ^* color system.
After that, the obtained L ^* value, a ^* value, and b ^* value were substituted into the following formula (1) to calculate the D value.
D=[(L ^* −27) ² +(a ^* −(−1)) ² +(b ^* −(−3)) ² ] ^1/2 (1)

(Chloride ion content, sulfate ion content)
For each example and each comparative example, using a low-pressure transfer molding machine (KTS-30, manufactured by Kotaki Seiki Co., Ltd.), the above sealing was performed under the conditions of a mold temperature of 175 ° C., an injection pressure of 9.8 MPa, and a curing time of 300 seconds. A hardened product of the sealing resin composition having a diameter of 50 mm and a thickness of 3 mm was obtained by transfer molding the sealing resin composition. Next, the above cured product was pulverized by freeze pulverization, 2 g of a powder sample was accurately weighed in a pressure cooker container, 40 ml of ultrapure water was added, the container was sealed, and the sample was shaken manually for 1 minute to make the sample familiar with water. . The container is placed in an oven set at 121° C., heated and pressurized continuously for 20 hours, allowed to cool to room temperature, and the inner solution is centrifuged and filtered to obtain a test solution. The liquid was analyzed by ion chromatography.

(laser mark property)
For each example and each comparative example, using a low-pressure transfer molding machine (KTS-30, manufactured by Kotaki Seiki Co., Ltd.), the above sealing was performed under the conditions of a mold temperature of 175 ° C., an injection pressure of 9.8 MPa, and a curing time of 300 seconds. A sealing resin composition is injected to seal a lead frame or the like on which a semiconductor element (silicon chip) is mounted, and a 16-pin SOP (semiconductor element is a HAST standard product TEG9 is used. The inner lead portion is bonded with a gold wire having a diameter of 25 μm.) was molded, and post-curing was performed at 175° C. for 2 hours to fabricate a semiconductor device. After that, among the obtained semiconductor devices, the encapsulating material, which is the cured product of the encapsulating resin composition, is subjected to a laser marking machine such as a mask type YAG laser manufactured by NEC Corporation (applied voltage 2.4 kV, A mark was printed using a pulse width of 120 μs, 15 A, 30 kHz, and 300 mm/sec, and the markability was visually evaluated in the following three stages.
A: Engraving can be read clearly B: Engraving can be read to the extent that it can be used C: Engraving cannot be read and cannot be used

(permittivity, dielectric loss tangent)
For each example and each comparative example, using a low-pressure transfer molding machine (KTS-30 manufactured by Kotaki Seiki Co., Ltd.), sealing was performed under the conditions of a mold temperature of 175 ° C., an injection pressure of 7.4 MP, and a curing time of 120 seconds. A test piece having a diameter of 50 mm and a thickness of 3 mm was prepared by injection molding the resin composition for the test, and cured by heat treatment at 175° C. for 30 minutes. After that, the obtained test piece was sandwiched between electrodes, and the dielectric constants ε ₁ and ε ₁₀ and the dielectric loss tangents δ ₁ and δ ₁₀ at 1 GHz and 10 GHz were measured using a dielectric constant measuring device (manufactured by AET Co., Ltd., product name ASMS01Oc1). was measured.

As shown in Table 1, in the examples, encapsulating resin compositions having good blackness and dielectric properties while ensuring mechanical properties and high-temperature reliability were obtained.

This application claims priority based on Japanese Patent Application No. 2021-118636 filed on July 19, 2021, and the entire disclosure thereof is incorporated herein.

Claims (9)

a coloring agent;
a thermosetting resin;
a curing agent;
an inorganic filler;
A sealing resin composition containing
The coloring material is carbon particles having a resistivity of 1.0×10 ¹ Ω·cm or more and 1.0×10 ¹⁴ Ω·cm or less when a load of 20 kN is applied, which is measured by <Method 1> below. including
The content of the carbon particles is 0.05% by weight or more and 5% by weight or less with respect to the total solid content of the sealing resin composition,
Using L ^*, a ^* , b ^* defined by the CIE1976L ^* a ^* b ^* color system of the cured product obtained by curing the encapsulating resin composition by heat treatment at 175°C for 30 minutes, Formula (1) below:
D=[(L ^* −27) ² +(a ^* −(−1)) ² +(b ^* −(−3)) ² ] ^1/2 (1)
The D value defined by is 3.2 or less,
The encapsulating resin composition , wherein the sulfur content in the carbon particles is 150 ppm or less .
<Method 1>
1 g of carbon particles is set in a powder resistance measurement system ohmmeter (Hiresta UX/Loresta GP, MCP-PD51 type, manufactured by Nitto Seiko Analytic Co., Ltd.), and the specific resistance value is measured when a load of 20 kN is applied. In the sealing resin composition according to claim 1,
In the X-ray diffraction spectrum measured by the X-ray diffraction method using CuKα rays as a radiation source, with 2θ on the horizontal axis and diffraction intensity on the vertical axis, the straight line selected by <Method 2 > below is removed as the background. The encapsulating resin composition, wherein the crystallite size Lc in the c-axis direction (direction perpendicular to the (002) plane) of the (002) plane of the carbon particles obtained after the above is 50 Å or less.
<Method 2 >
(1) In the X-ray diffraction spectrum in which the horizontal axis is 2θ and the vertical axis is diffraction intensity, one of the points at 2θ = 10° or 2θ = 15° and the point at 2θ = 30° or 2θ = Select any one of the 35° points and connect the two selected points with a straight line to create a total of four straight lines.
(2) Select one of the four straight lines created in (1) above.
(3) Find the area S surrounded by the straight line selected in (2) above and the X-ray diffraction spectrum positioned below the straight line in the region where 2θ is 10° or more and 35° or less.
(4) The steps (2) and (3) are repeated for each of the four straight lines created in (1) above, and the straight line L that minimizes the obtained area S is specified.
(5) Let the straight line L be a background straight line. 3. The encapsulating resin composition according to claim 1, wherein the carbon particles have a chlorine content of 50 ppm or less. In the sealing resin composition according to claim 1 or 2,
The thermosetting resin is selected from the group consisting of novolak type epoxy resins, polyfunctional epoxy resins, phenol aralkyl type epoxy resins, naphthol type epoxy resins, triazine core-containing epoxy resins, and bridged cyclic hydrocarbon compound-modified phenol type epoxy resins. A sealing resin composition containing one or more epoxy resins. 3. The encapsulating resin composition according to claim 1, wherein said curing agent comprises a phenolic resin-based curing agent. In the sealing resin composition according to claim 1 or 2,
An encapsulating resin composition having a flow length of 50 cm or more and 300 cm or less when measured using a mold for spiral flow measurement according to EMMI-1-66 under the conditions of a mold temperature of 175° C. and a measurement time of 5 minutes. In the sealing resin composition according to claim 1 or 2,
The ratio ε ₁ /ε ₁₀ of the dielectric constant ε 1 at 1 GHz _of the cured product obtained by curing the sealing resin composition by heat treatment at 175 ° C. for 30 minutes and the dielectric constant ε ₁₀ at 10 GHz is A resin composition for sealing, which is 0.9 or more and 1.2 or less. In the sealing resin composition according to claim 1 or 2,
The ratio _δ1 / _δ10 between the dielectric loss tangent _δ1 at 1 GHz and the dielectric loss tangent _δ10 at 10 GHz of the cured product obtained by curing the sealing resin composition by heat treatment at 175°C for 30 minutes is The resin composition for sealing, which is 0.8 or more and 1.1 or less. An electronic device in which a semiconductor element is encapsulated with a cured product of the encapsulating resin composition according to claim 1 or 2.