TW201839046A - Epoxy resin composition, electric/electronic parts and manufacturing method of electric/electronic parts capable of preventing electric/electronic parts such as coil products from insulation damage under high voltage and having excellent reliability - Google Patents

Abstract

This invention provides a resin composition useful as an epoxy resin composition for ignition coils, in addition, it is capable of preventing electric/electronic parts such as coil products from insulation damage under high voltage and with excellent reliability. This invention relates to an epoxy resin composition and electric/electronic parts 1, wherein the epoxy resin composition contains (A) epoxy resin, (B) inorganic filler, and (C) thermal cationic polymerization initiator as essential ingredients; the electric/electronic parts 1 has electric/electronic part elements 2 and cured resin product 3 of the epoxy resin composition for encapsulating the electric/electronic part elements 2.

Description

Epoxy resin composition, electric ‧ electronic parts and electrical ‧ electronic parts manufacturing method

The present invention relates to an epoxy resin composition, an electrical/electronic component, and a method of manufacturing an electrical/electronic component.

Previously, high-grade impregnation and high electrical insulation were required for the motor for rail vehicles, the rotating electrical machine for generators, and the coil products for various electrical machines. From this point of view, thermal hardening is often used in the insulation treatment of coils. A resin composition, especially an epoxy resin composition. For example, the acid anhydride-curable epoxy resin composition is excellent in mechanical properties, electrical insulation properties, and high voltage characteristics at a high temperature, and can be improved by being used for insulation treatment of a coil of a rotating electrical machine that exerts large vibration during operation. And reliability (for example, refer to Patent Document 1). However, since a high voltage is applied to a coil (for example, an ignition coil) used in various types of equipment such as automobiles, if only a normal epoxy resin composition is used, insulation may be insufficient and insulation breakdown may occur. Further, there is a case where cracks occur in the cured resin of the sealing resin due to thermal stress or mechanical stress of the cured resin due to the cooling cycle. When a crack occurs in the cured resin sealing material, when an electric current flows through the ignition coil, an abnormal discharge or the like occurs in the cracked portion, and the ignition coil cannot be normally operated. Therefore, crack resistance is also required for the cured resin of the sealing resin. As a general method for improving the crack resistance of the cured resin of the sealing resin, it is considered to add a large amount of cerium oxide to the resin composition to reduce the coefficient of linear expansion. However, this method is caused by the impregnation of the liquid resin component, and the gap of the necessary copper wire is blocked by the cerium oxide fine powder. As a result, the resin composition is not impregnated between the secondary windings, resulting in poor insulation. In view of such a situation, a two-component epoxy resin composition containing spherical cerium oxide having an average particle diameter of 2 μm or less, two kinds of acid anhydrides, a hardening accelerator, and an epoxy resin as constituent components is known (for example, a reference patent) Literature 2). The purpose of the two-component epoxy resin composition is to provide a small amount of inorganic filler which is deposited during storage, has low viscosity, is excellent in injection workability, has a small coefficient of linear expansion, is excellent in heat cycle resistance, and is excellent in heat resistance. Electronic machine. In addition, the inventors of the present invention have proposed a resin composition for impregnation of a mold coil, which comprises cerium oxide having an average particle diameter of 10 to 30 μm and an average particle diameter of 0.01 to 1.5 μm in order to increase the dielectric breakdown voltage of the cured resin. Particles (for example, refer to Patent Document 3). [PRIOR ART DOCUMENT] [Patent Document 1] Japanese Patent Laid-Open No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. Bulletin

[Problems to be Solved by the Invention] In addition, for the recent ignition coils, the requirements for improving the withstand voltage performance have become strict, for example, the withstand voltage performance at normal temperature (25 ° C) is continuously increased to 28 MV/m or more and further The withstand voltage performance under heating at around 100 °C is also required to maintain the characteristics of 20 MV/m or more. However, the resin composition used so far is difficult to achieve such properties. In view of the above, it is an object of the present invention to provide a resin composition for use in an epoxy resin composition such as an ignition coil, and to obtain an electrical/electronic product such as a coil product which is suppressed in insulation breakdown at a high voltage and which is excellent in reliability. Components. Moreover, an object of the present invention is to provide an electric/electronic component excellent in reliability as described above and a method of manufacturing the same. [Means for Solving the Problems] The inventors of the present invention have made intensive studies to solve the above problems, and as a result, it has been found that a resin composition is prepared by using a specific thermal cationic polymerization initiator for an epoxy resin, thereby ensuring a coil or the like. The electric and electronic component elements are excellent in high impregnation property and formability, and a cured product having high thermal conductivity and high insulation breakdown voltage with high reliability can be obtained, and the present invention has been completed. That is, the epoxy resin composition of the present invention is characterized by containing (A) an epoxy resin, (B) an inorganic filler, and (C) a thermal cationic polymerization initiator as essential components. Moreover, the electric/electronic component of the present invention is characterized by having an electric/electronic component component and a cured product of the epoxy resin composition of the present invention in which the electrical/electronic component component is sealed. Moreover, the method for producing an electric/electronic component according to the present invention is characterized in that an electric/electronic component is placed in a mold, and the epoxy resin composition for casting of the present invention is injected into the mold to be semi-cured. The semi-hardened casting epoxy resin composition is taken out from the above mold and completely hardened by post-hardening. [Effect of the Invention] According to the epoxy resin composition of the present invention, an epoxy resin composition having a high impregnation property with an electric/electronic component such as a coil and having a shape suitable for casting by impregnation can be provided. Moreover, a cured product having a high thermal conductivity and a high dielectric breakdown voltage can be obtained. According to the electric and electronic component of the present invention and the method of manufacturing the same, an electric/electronic component having high thermal conductivity, high dielectric breakdown voltage, and high reliability can be obtained.

Hereinafter, the present invention will be described in detail with reference to an embodiment. The epoxy resin composition used in the present embodiment contains (A) an epoxy resin, (B) an inorganic filler, and (C) a thermal cationic polymerization initiator as essential components. The epoxy resin (A) used in the present embodiment is not particularly limited as long as it is an epoxy resin having two or more glycidyl groups (epoxy groups) in one molecule, and is preferably liquid. Epoxy resin. Examples of such an epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, novolac type epoxy resin, and glycidyl ester type epoxy resin. Polyglycidyl ether, trifunctional phenolic epoxy resin, and the like. These may be used alone or in combination of two or more. In the case where two or more kinds are used in combination, it may be liquid as long as it is mixed. The (A) epoxy resin preferably contains an alicyclic epoxy resin. The dielectric breakdown strength can be further improved by using an alicyclic epoxy resin. In general, the alicyclic epoxy resin is preferably used in combination with another epoxy resin. For example, when the (A) epoxy resin is 100 parts by mass, it is 60 to 90 parts by mass based on the bisphenol A type epoxy resin. The mixing ratio of 10 to 40 parts by mass contains an alicyclic epoxy resin. If the alicyclic epoxy resin is less than 10 parts by mass, the dielectric breakdown strength at a high temperature is not improved, and the shrinkage dent or the like is deteriorated. On the other hand, if it exceeds 40 parts by mass, the viscosity is lowered, and the filler is settled and stored stably. Sexually impaired. The inorganic filler (B) used in the present embodiment is not particularly limited as long as it is an inorganic filler blended in such a resin composition. Examples of the (B) inorganic filler include cerium oxide, aluminum oxide, calcium carbonate, aluminum hydroxide, talc, and mica. As the (B) inorganic filler, it is preferred to use cerium oxide. As the cerium oxide used this time, either crystalline cerium oxide or molten cerium oxide can be used, and as the molten cerium oxide, crushed molten cerium oxide, spherical molten cerium oxide, or the like can be used. . Examples of the crystalline cerium oxide include CRYSTALITE A-AC, CRYSTALITE A-1, CRYSTALITE C (above, manufactured by Longsen Co., Ltd., trade name). Examples of the crushed molten cerium oxide include FUSELEX RD-8, FUSELEX RD-120, FUSELEX E-1, FUSELEX E-2, MSR-15, MSR-3500, and TZ-20 (the above is Longsen Co., Ltd.) Company manufacturing, trade name) and so on. Examples of the spherical molten cerium oxide include FB-5D and FB959 (the above are manufactured by DENKA Co., Ltd., trade name). Further, regarding the vermiculite in the crystalline ceria, the inclusion of the vermiculite can improve the dielectric breakdown strength of the cured product upon heating. Further, the nature of the fractured vermiculite is a fine powder, which is restricted in workability and filling amount, and hinders the reaction of the thermal cationic polymerization initiator, so that workability and formability are preferably good. It is also possible to suppress the globular vermiculite powder which is inhibited by the above reaction. The blending ratio of the (B) inorganic filler is preferably 30 to 80% by mass in the resin composition. When the amount of the inorganic filler (B) is less than 30% by mass, the curability is inferior, and it is difficult to improve the mechanical strength and the crack resistance. When the amount is more than 80% by mass, the filler in the resin composition is precipitated. The viscosity is increased, the workability is lowered, and the impregnation property of the electric/electronic component is lowered. Further, the (B) inorganic filler can be subjected to surface modification by a treatment with a coupling agent to obtain an insulation reliability and mechanical strength of a more excellent cured product. Examples of the coupling agent which can be used herein include a decane coupling agent, a titanium coupling agent, and an aluminum coupling agent, and a decane coupling agent is particularly preferable in terms of excellent properties such as moisture resistance. Examples of the decane-based coupling agent include 3-glycidoxypropyltrimethoxydecane, 3-glycidoxypropyltriethoxydecane, methyltrimethoxydecane, and γ-aminopropylpropane. Triethoxy decane, γ-aminopropyltrimethoxydecane, N-aminoethylaminopropyltrimethoxydecane, N-phenyl-γ-aminopropyltrimethoxydecane, N -3-(4-(3-Aminopropyloxy)butoxy)propyl-3-aminopropyltrimethoxydecane, these may be used alone or in combination of two or more. The (C) thermal cationic polymerization initiator used in the present embodiment is a compound which generates a cationic species or a Lewis acid by heating, and a known thermal cationic polymerization initiator can be used. As the thermal cationic polymerization initiator, the polymerization initiation temperature is preferably 60 ° C or more and 160 ° C or less. When the polymerization initiation temperature is extremely low, the time that can be used is shortened, and workability is disadvantageous. Further, if the polymerization initiation temperature is a high temperature, there is a risk of damage to the built-in electronic component. In the present specification, the term "polymerization initiation temperature" means a temperature at which an acid is generated and which is a reaction initiation temperature which has little effect on workability and parts. Examples of the (C) thermal cationic polymerization initiator include aromatic sulfonium salts such as benzyl sulfonic acid, thiophene sulfonium salts, tetrahydrothiophene sulfonium salts, benzyl ammonium salts, pyridinium salts, phosphonium salts, and carboxylic acids. An acid ester, a sulfonic acid ester, an amine imide or the like is preferable, and among them, an aromatic phosphonium salt is preferred. As the (C) thermal cationic polymerization initiator, commercially available products can be used, and for example, trade names "San-Aid 60L", "San-Aid 100L", "San-Aid 150L" manufactured by Sanshin Chemical Co., Ltd., or The trade names "TA-100", "TA-120", and "TA-160" manufactured by San-Apro. The compounding amount of the (C) thermal cation generating agent is preferably in the range of 0.5 to 1.5 parts by mass based on 100 parts by mass of the (A) epoxy resin. When the amount is less than 0.5 parts by mass, the reactivity is remarkably slow, and the heat of the high temperature causes the cured product to shrink, which tends to cause strain or breakage of the electric/electronic parts. On the other hand, if it exceeds 2.0 parts by mass, There is a decrease in fluidity at the time of injection due to shortening of the service life, and an unfilled portion is generated. In the epoxy resin composition for casting of the present embodiment, the components (A) to (C) are used as essential components, and a curing accelerator other than the (C) thermal cationic polymerization initiator may be further added in order to improve the curing property. Examples of the hardening accelerator other than the (C) thermal cationic polymerization initiator which can be used herein include aromatic dimethyl urea, aliphatic dimethyl urea, and 3-(3,4-dichlorophenyl). -1,1-dimethylurea (DCMU), 3-(3-chloro-4-methylphenyl)-1,1-dimethylurea, 2,4-bis(3,3-dimethylureido) a urea such as toluene; a tertiary amine compound such as benzyldimethylamine, 1,8-diazabicyclo (5.4.0) undecene-7 or triethylamine; 2-ethyl-4-methylimidazole , imidazole compounds such as 1-benzyl-2-methylimidazole, 2-methylimidazole, 2-ethylimidazole, 2-isopropylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole An organic phosphonium salt compound such as a triphenylphosphine salt. These hardening accelerators may be used alone or in combination of two or more. In the epoxy resin composition of the present embodiment, the components (A) to (C) described above are essential components, and it is preferred to use two liquids of a main component and a curing agent, and to use them before mixing. In this case, the main component is the component (A) to (B) as a constituent component, and other components such as a polymerization inhibitor, a pigment, a dye, and a defoaming may be added as needed within a range not departing from the object of the present invention. Agent, leveling agent, coupling agent, and other components. Further, the curing agent contains (C) a thermal cationic polymerization initiator as a constituent component. Further, a hardening accelerator, a filler according to the case, or the like may be further added to the curing agent. The usual reason for making two-liquidity is to consider workability and service life. Next, an electric and electronic component using the epoxy resin of the present embodiment and a method of manufacturing the same will be described. As shown in FIG. 1 , the electric/electronic component of the present embodiment includes an electric/electronic component 2 such as a coil and an internal component, and an electric/electronic component 1 of a cured resin 3 that seals the electrical/electronic component 2 . Here, the electric/electronic component element 2 has a lead frame 2a. The electric/electronic component element 2 is not particularly limited as long as it is an electric/electronic component that is subjected to resin sealing, such as a coil and an internal component. Further, the resin cured product 3 is obtained by sealing the electric/electronic component 2 and curing the epoxy resin composition. Next, a method of manufacturing an electric/electronic component according to the present embodiment will be described. The electric/electronic component of the present embodiment can be manufactured, for example, by a vacuum pressure impregnation process to produce an electrical/electronic component such as a coil or an internal component. This vacuum pressure impregnation treatment can be achieved, for example, by accommodating an electrical/electronic component in a casing having a shape other than an electric/electronic component, and injecting the above-described housing into the casing in which the electrical/electronic component is housed. The resin composition of the embodiment is subjected to vacuum impregnation treatment (depressurization impregnation treatment) and pressure treatment in this order. In this case, the vacuum impregnation treatment is preferably carried out, for example, at a temperature of 40° C. or more and 80° C. or less, a pressure of 100 Pa or more and 450 Pa or less, and a treatment time of 30 minutes or more and 120 minutes or less. Further, the pressurization treatment is preferably carried out, for example, under the conditions of a pressure of 2 × 10 ⁵ Pa or more and 10 × 10 ⁵ Pa or less, and a time of 15 minutes or longer and 120 minutes or shorter. Then, after returning to normal pressure by the vacuum-pressure impregnation treatment, the resin composition is heated and hardened to produce an electric/electronic component. The heating at this time is preferably carried out, for example, at a temperature of 60 ° C or higher and 200 ° C or lower for 5 minutes or longer and 60 minutes or shorter. Further, it is possible to use a molding method of E-LIM (Liquid Injection Molding) which is easily produced in a mold without using a casing. The E-LIM molding method is an injection molding method in which a liquid resin composition is injected into a mold by pressurization, and by using the molding method, the hardening time of the resin in the previous casting method as described above is required to be 5 to 10 hours can be formed in tens of minutes, which can greatly improve productivity. In the E-LIM molding method, since the reaction can be taken out from the mold after the curing reaction in a short time, the productivity can be improved. Further, since most of the hardening can be performed by post-hardening, it is not necessary to set complicated molding and hardening conditions in the molding stage. In the E-LIM molding method, first, a mold which can form a shape other than the sealing resin of the electric/electronic component 1 by injecting the resin composition is prepared. Then, the electrical and electronic component components are placed and fixed at specific positions within the mold. Fig. 2 is a view showing a state in which the resin composition is injected in the next step, and therefore, a description will be given with reference to Fig. 2 . In order to arrange the electric/electronic component component 2 at a specific position as described above, the electric/electronic component component 2 may be placed at a specific position of the lower mold 11 first, and the upper die 12 may be covered from above. At this time, the body of the electric/electronic component 2 is placed in the center of the gap in the mold by the lead frame 2a. Then, the epoxy resin of the above-described embodiment is injected and injected into the mold, and is semi-cured by heating. The injection molding die used in the present embodiment includes a lower mold 11 and an upper mold 12, and concave portions 11a and 12a are formed in the lower mold 11 and the upper mold 12, respectively. The recesses 11a, 12a constitute a cavity 13. Further, the upper mold 12 is provided with a gate 14 which is a resin injection port that communicates with the cavity 13, and an injection nozzle 15 for injecting the liquid epoxy resin composition 3a is connected to the gate 14. The liquid epoxy resin composition 3a is injected into the cavity 13 through the gate 14 from the injection nozzle 15 to perform injection molding. At this time, the injection of the epoxy resin composition is carried out under the conditions of a nozzle discharge pressure of 2 to 6 MPa, a nozzle injection resin temperature of 30 to 60 ° C, and a molding time of 10 to 20 minutes. Further, as a temperature condition for semi-curing the epoxy resin composition, it is preferably 70 to 100 ° C in the intermediate temperature region, and the time is preferably about 5 to 25 minutes. When the temperature is less than 70 ° C, the curing reaction is not sufficiently performed. When the temperature exceeds 100 ° C, the curing progresses rapidly, and the epoxy resin composition is not uniformly filled in the gap portion of the electric/electronic component 2 . If the time is less than 5 minutes, the curing or gelation is insufficient, and it is difficult to take out the molded article from the mold. If the molding time exceeds 25 minutes, the molding time is long, and the productivity cannot be sufficiently improved. After the resin composition is semi-hardened as described above, the mold is opened, and the electric/electronic component 2 sealed by the epoxy resin composition in a semi-hardened state is taken out, and further heated and post-cured, whereby the epoxy resin composition is obtained. Completely hardened to obtain electrical and electronic parts 1. This post-hardening can be performed, for example, by heating at a temperature of 100 ° C or higher for about 1 to 2 hours. [Examples] Next, the present invention will be described in more detail by way of examples. Furthermore, the invention is not limited to the following examples. (Examples 1 to 7 and Comparative Examples 1 to 4) Each of the raw materials was stirred and mixed to a uniform ratio at the mixing ratios shown in Tables 1 and 2 to prepare a two-component liquid epoxy resin composition of a main component and a curing agent. [Table 1] [Table 2] Further, the materials used in the examples and comparative examples are as follows. [(A) Epoxy Resin] (A1) General Epoxy Resin (Mitsui Petrochemical Co., Ltd., trade name: Epomic R140P; bisphenol A type) (A2) alicyclic epoxy resin (manufactured by Daicel Co., Ltd., trade name: Celloxide 2021P) [(B) inorganic filler] (B1) spherical vermiculite 1 (manufactured by Micron, trade name: TS15-103-20; average particle diameter 10.8 μm) (B2) spherical vermiculite 2 (Micron company Manufactured, trade name: TS16-070-72; average particle size 30.7 μm) (B3) Spherical molten cerium oxide (manufactured by Micron, trade name: S3030; average particle size 4 μm) [(C) Thermal cationic polymerization Starting agent] (C1) strontium salt 1 (manufactured by San-Apro Co., Ltd., trade name: TA-100) (C2) strontium salt 2 (manufactured by Sanshin Chemical Industry Co., Ltd., trade name: San-Aid SI-100L) (C3)鏻 salt (manufactured by Nippon Chemical Industry Co., Ltd., trade name: Hishicolin PX-4B) [(D) Hardening accelerator other than (C)] (D1) quaternary ammonium salt (manufactured by Nippon Oil & Fats Co., Ltd., trade name: Nissan Cation M2 -100R) (D2) imidazole-based catalyst 1 (manufactured by San-Apro Co., Ltd., trade name: U-CAT2030) (D3) imidazole-based catalyst 2 (manufactured by Shikoku Chemical Industry Co., Ltd., trade name: 1B2PZ) [(E) Additives] (E1) Defoamer (Momentive Performance Mate) Manufactured by rials, trade name: TSA720) (E2) black pigment (manufactured by AICA Industrial Co., Ltd., trade name: ECB602) Next, the electrical and electronic component elements were sealed by the liquid epoxy resin composition prepared in each example. First, the electrical and electronic component to be sealed is housed in the concave portion of the mold under the mold, and the upper mold is fitted to assemble the mold. Next, the epoxy resin compositions obtained in the respective examples were introduced into the nozzle mains of the injection nozzles, respectively, and evacuated in a cavity between the lower mold and the upper mold by a vacuum pump up to 10 Torr. The plunger was actuated, and the filled epoxy resin composition was injected into the cavity at a filling speed of 0.5 L/min and an injection temperature of 60 ° C as shown in FIG. 2, and then the lower mold and the upper portion were pressed under a pressure of 0.5 MPa. The mold was heated, and the epoxy resin composition was heat-hardened (semi-hardened) at 100 ° C for 10 minutes. Thereafter, the mold was opened, and the semi-cured material was taken out from the mold, and then post-cured at 100 ° C for 2 hours, at 150 ° C for 2 hours, and at 180 ° C for 2 hours, and then sealed with a resin cured product. Electrical and electronic parts. The epoxy resin composition and the electric/electronic parts obtained in each of the above examples and comparative examples were evaluated for various characteristics, and the results are shown in Tables 3 and 4. Further, the evaluation methods of these characteristics are also disclosed in detail below. [table 3] [Table 4] <Resin Composition> (1) Viscosity For the epoxy resin composition, according to the viscosity measurement method of JIS C 2105, the rotor No. 3 was used at a temperature of 70 ° C and a number of revolutions of 12 rpm by a B type viscometer. The viscosity of the mixture was measured. (2) Specific gravity Using a pycnometer of a certain volume, the epoxy resin composition is placed in a pycnometer at room temperature, and the specific gravity is determined from the volume and mass. (3) Gelation time According to the test tube method of JIS C 2105, 10 g of the epoxy resin composition was weighed and placed in a test tube, and the time until the resin composition was gelled in an oil bath at 110 ° C was measured. <Cured product> (4) Filling property of the hardened material After injecting 40 g of the mixed solution into a plastic test tube, it was hardened under specific hardening conditions (100 ° C for 1 hour and further at 150 ° C for 1 hour). The upper portion of the cured product having a height of 120 mm and a diameter of 17 mm f was cut by 10 mm, and the specific gravity (above) of the cured product was measured. Similarly, the lower portion was cut 10 mm, and the specific gravity (lower) of the cured product was measured. Further, the center portion was cut by 10 mm, and the specific gravity (center) of the cured product was measured. Further, with respect to the specific gravity of the cured product obtained in this manner, the ratio of the specific gravity (upper) of the cured product to the specific gravity (lower) of the cured product [(hardened specific gravity (above) / hardened specific gravity (lower)) × 100] was calculated. The value obtained by this calculation is expressed in the table as "the ratio of the specific gravity of the cured product above and below." A ratio of close to 100% means that the difference between the ratios of the fillers above and below is small, and no sedimentation of the filler occurs. (5) Glass transition point (Tg) 5 × 5 × 5 mm prepared by curing the epoxy resin composition at 70 ° C for 2 hours, at 90 ° C for 2 hours, and finally at 110 ° C for 2 hours. The sample was heated by a thermal analyzer TMA/SS150 (manufactured by Seiko Instruments Co., Ltd.) from room temperature to 250 ° C (temperature up rate 10 ° C / min) to measure the thermal expansion curve, and the glass transition point was determined from the midpoint of the displacement point. (Tg). (6) Flexural strength and flexural modulus The epoxy resin composition was cured at 70 ° C for 2 hours, at 90 ° C for 2 hours, and finally at 110 ° C for 2 hours to prepare a test piece (width: 10 mm, height) : 4 mm, length: 100 mm), and the bending strength and bending modulus at a temperature of 25 ° C were measured in accordance with JIS K 6911. (7) Bending elongation The epoxy resin composition was cured at 70 ° C for 2 hours, at 90 ° C for 2 hours, and finally at 110 ° C for 2 hours to prepare a test piece (width: 10 mm, height: 4 mm, Length: 100 mm), and the bending elongation at a temperature of 25 ° C was measured in accordance with JIS K 6911. (8) Thermal conductivity The epoxy resin composition was cured at 70 ° C for 2 hours, at 90 ° C for 2 hours, and finally at 110 ° C for 2 hours to prepare a cylindrical test piece (diameter: 100 mm, thickness) : 20 mm), and the thermal conductivity at a temperature of 25 ° C was measured by a probe method. (9) Volume resistivity The epoxy resin composition was cured at 70 ° C for 2 hours, at 90 ° C for 2 hours, and finally at 110 ° C for 2 hours to prepare a cylindrical test piece (diameter: 100 mm, thickness). : 2 mm), and the volume resistivity at a temperature of 25 ° C and 160 ° C was measured in accordance with JIS K 6911. (10) Insulation breaking strength The epoxy resin composition was cured at 70 ° C for 2 hours, at 90 ° C for 2 hours, and finally at 110 ° C for 2 hours to prepare a test piece (width: 100 mm, length: 100 mm) , thickness: 1 mm), and the dielectric breakdown strength at a temperature of 25 ° C and 150 ° C was measured in accordance with JIS K 6911. (11) Thermal expansion coefficient For the epoxy resin composition which was cured at 70 ° C for 2 hours, at 90 ° C for 2 hours, and finally at 110 ° C for 2 hours, it was molded into a sample of 5 × 5 × 20 mm. The thermal analysis device TMA/SS150 (manufactured by Seiko Instruments Co., Ltd.) was used to measure the thermal expansion coefficients α ₁ and α ₂ at a temperature increase rate of 5 ° C/min and a load of 49.03 mN. Here, α ₁ is a thermal expansion coefficient of 25 ° C to Tg, and α ₂ is a linear thermal expansion coefficient of Tg to 250 ° C. [Comprehensive judgment] The characteristics of the resin composition and the cured product of the present embodiment were evaluated in the following manner, and scores were assigned to the respective characteristics, and comprehensive judgment was performed based on the total score. In the overall judgment, the total score is 25 points or more, ○, 23 to 24 minutes, Δ, 22 points or less, x, and the results of the determination are shown in Tables 3 to 4. (Evaluation of the sedimentation property) The ratio of the upper part of the hardened material obtained above and the specific gravity of the hardened material below is set to 99% or more, and it is set to 5 points, and 95% or more and less than 99% is set to 3 points. Less than 95% is set to 1 point. (Glass transfer evaluation price) The glass transition point obtained above was set to 5 minutes of 110 ° C or more, 3 degrees of 100 ° C or more and less than 110 ° C, and 1 minute of less than 100 ° C. (Evaluation of Thermal Conductivity) The thermal conductivity obtained above was 0.5 W/m·K or more and 5 minutes, and less than 0.5 W/m·K was set to 1 minute. (Evaluation of dielectric breakdown strength) The insulation breaking strength obtained above is set to 5 MV/m or more, and 15 MV/m or more and less than 25 MV/m are set to 3 points, which is less than 15 MV/m. Set to 1 point. This evaluation was performed under the same standard at any of 25 ° C and 150 ° C. (E-LIM Formability (Pore) Evaluation) The electrical and electronic parts obtained by the above-described molding were cut at an arbitrary cut surface, and the number of pores in the cured resin in the cut surface was visually observed. It was confirmed that the number of pores was 5, the number of pores was 1 to 4, and the number of pores was 5 or more, and the evaluation was performed by setting the number of pores to 5 or more. According to the above, the epoxy resin composition of the present embodiment has high impregnation properties, is suitable for molding by casting impregnation, and can obtain a cured product having high thermal conductivity and high dielectric breakdown voltage. The electrical and electronic parts obtained from the epoxy resin composition have high reliability.

1‧‧‧Electrical and electronic parts

2‧‧‧Electrical and electronic parts

2a‧‧‧ lead frame

3‧‧‧Resin cured

3a‧‧‧Epoxy Resin Composition

11‧‧‧下模

11a, 12a‧‧‧ recess

12‧‧‧上模

13‧‧‧ cavity

14‧‧‧ gate

15‧‧‧Injection nozzle

Fig. 1 is a cross-sectional view showing a schematic configuration of an electric/electronic component according to the embodiment. Fig. 2 is a cross-sectional view for explaining a method of manufacturing an electric/electronic component according to the embodiment.

Claims (6)

An epoxy resin composition comprising: (A) an epoxy resin, (B) an inorganic filler, and (C) a thermal cationic polymerization initiator as essential components. The epoxy resin composition of claim 1, wherein the (C) thermal cationic polymerization initiator comprises an aromatic onium salt. The epoxy resin composition of claim 1 or 2, wherein the (B) inorganic filler comprises spherical vermiculite. The epoxy resin composition according to any one of claims 1 to 3, wherein the (A) epoxy resin comprises 5 to 40% by mass of an alicyclic epoxy resin. An electric/electronic component, comprising: an electric/electronic component, and a cured product of the epoxy resin composition according to any one of claims 1 to 4, wherein the electrical/electronic component is sealed. A method of manufacturing an electric/electronic component, wherein an electric/electronic component is placed in a mold, and an epoxy resin composition according to any one of claims 1 to 4 is injected into the mold and semi-hardened. The semi-hardened epoxy resin composition is taken out from the mold and completely cured by post-hardening.