Curable resin composition and its cured product

Abstract

The present invention provides an epoxy resin composition and a cured product that exhibit excellent heat resistance and low water absorption. [Solution] A curable resin composition comprising an epoxy resin represented by the following formula (1) and a reactive compound. TIFF2026086312000012.tif53170 (In equation (1), each of the multiple R groups exists independently and represents a hydrocarbon group with 1 to 5 carbon atoms. In each benzene ring substituted with R, the sum of the carbon atoms of the multiple R groups is between 2 and 8. k is an integer between 1 and 4. n is the average number of repeats, between 1 and 20.)

Description

Technical Field

[0001] The present invention relates to a curable resin composition containing an epoxy resin having a specific structure and a cured product thereof, and is suitably used for electrical and electronic components such as semiconductor encapsulation materials, printed wiring boards, build-up laminated boards, and optical waveguide devices, lightweight and high-strength materials such as carbon fiber reinforced plastics and glass fiber reinforced plastics, and 3D printing applications.

Background Art

[0002] Epoxy resins are excellent in electrical properties (dielectric constant, dielectric tangent, insulation), mechanical properties, adhesiveness, thermal properties (heat resistance, etc.), etc., and are widely used in fields such as electrical and electronic fields such as cast products, laminated boards, and IC encapsulation materials, structural materials, adhesives, and paints.

[0003] In recent years, in the electrical and electronic fields, further improvement of various properties such as flame retardancy, moisture resistance, adhesion, dielectric properties, etc. of resin compositions, improvement of purity, reduction of viscosity for high filling of fillers (inorganic or organic fillers), and improvement of reactivity for shortening the molding cycle are required (Patent Documents 1 to 3). In addition, as structural materials, materials that are lightweight and have excellent mechanical properties are required in aerospace materials, leisure and sports equipment applications, etc. Especially in the semiconductor encapsulation field and substrates (the substrate itself or its peripheral materials), as the semiconductor evolves, it becomes thinner, stacked, systematized, and three-dimensional, and very high-level required properties such as heat resistance and high fluidity are required. In particular, with the expansion of plastic packages to in-vehicle applications, the requirement for heat resistance improvement has become even more severe. Specifically, due to the increase in the driving temperature of semiconductors, very high heat resistance is required. In particular, with the recent trend towards wide-bandgap semiconductors, it has also become necessary to cope with driving temperatures of 175°C or even 200°C or higher (Non-Patent Documents 1 and 2).

Prior Art Documents

Non-Patent Documents

[0004] [Non-Patent Document 1] STRJ Report 2008, Semiconductor Roadmap Expert Committee, FY2008 Report, Chapter 8, pp. 1-1, [online], March 2009, JEITA (Japan Electronics and Information Technology Industries Association), Semiconductor Technology Roadmap Expert Committee, [Retrieved May 30, 2012].<http: / / strj-jeita.elisasp.net / strj / nenjihоukоku-2008.cfm> [Non-Patent Document 2] Takakura, Nobuyuki et al., Matsushita Electric Works Technical Report, Automotive Device Technology, High-Temperature Operation for Automotive Applications C, No. 74, Japan, May 31, 2001, pp. 35-40. [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2015-147854 [Patent Document 2] Japanese Patent Publication No. 2008-195751 [Patent Document 3] Japanese Patent Publication No. 2010-018669 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] However, when heat resistance is improved to withstand operating temperatures of 175°C or even 200°C or higher, water absorption characteristics generally deteriorate, making it difficult to achieve both performance characteristics and water absorption.

[0007] This invention has been made in view of the above circumstances, and aims to provide a curing resin composition with excellent heat resistance and low water absorption, and a cured product thereof. [Means for solving the problem]

[0008] In other words, the present invention relates to the following [1] to [5]. In this application, "(numerical value 1) to (numerical value 2)" indicates that upper and lower limits are included. [1] A curable resin composition comprising an epoxy resin represented by the following formula (1) and a reactive compound.

[0009] [ka]

[0010] (In equation (1), each of the multiple R groups exists independently and represents a hydrocarbon group with 1 to 5 carbon atoms. In each benzene ring substituted with R, the sum of the carbon atoms of the multiple R groups is between 2 and 8. k is an integer between 1 and 4. n is the average number of repeats, between 1 and 20.) [2] The curable resin composition according to item [1] above, wherein the reactive compound is at least one selected from the group consisting of epoxy resins other than the epoxy resin represented by formula (1), amine compounds, amide compounds, acid anhydride compounds, phenolic resins, active ester compounds, carboxylic acid compounds, maleimide compounds, cyanate compounds, isocyanate compounds, polyphenylene ether compounds, compounds having ethylenically unsaturated bonds, polyamide compounds, polyimide compounds, allyl compounds, polybutadiene and modified thereof, polystyrene and modified thereof, polyethylene and modified thereof, and benzoxazine compounds. [3] The curable resin composition according to item [1] or [2] above, further comprising an inorganic filler. [4] A curable resin composition according to any one of the preceding paragraphs [1] to [3], further comprising a curing accelerator. [5] A cured product obtained by curing any one of the curable resin compositions described in the preceding paragraphs [1] to [4]. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a curable resin composition and a cured product thereof that have excellent heat resistance and low water absorption. [Brief explanation of the drawing]

[0012] [Figure 1]The GPC chart of Synthesis Example 1 is shown. [Figure 2] The GPC chart of Synthesis Example 2 is shown.

Embodiments for Carrying out the Invention

[0013] Hereinafter, the embodiments according to the present invention (hereinafter also referred to as "the present embodiments") will be described in more detail.

[0014] The curable resin of the present embodiment contains an epoxy resin represented by the following formula (1) and a reactive compound.

Chemical formula

[0015] In formula (1) above, each of the multiple R groups exists independently and represents a hydrocarbon group having 1 to 5 carbon atoms, preferably 1 to 4 carbon atoms. If the number of carbon atoms is 6 or more, the heat resistance will be impaired and there is a risk of a decrease in the elastic modulus of the cured product, which is undesirable from the viewpoint of causing warping of the substrate when applied to a substrate material. If a hydrocarbon group is not introduced, the cured product will be more susceptible to water absorption, which may cause swelling during solder reflow. In each benzene ring substituted with R, the total number of carbon atoms of the multiple R groups is 2 to 8, preferably 2 to 6, more preferably 2 to 5. If the total number of carbon atoms is 1, the effect of reducing water absorption may not be sufficiently obtained, and if the total is 9 or more, there is a risk of increased viscosity due to an increase in molecular weight and a decrease in heat resistance. From the viewpoint of achieving both high fluidity and heat resistance, the total number of carbon atoms of each independently existing R group is preferably 2 to 8. k represents an integer from 1 to 4, preferably 2 to 4. For example, if k=2 and R are all methyl groups, the total number of carbon atoms in R is 2. n is the average value of the number of repeats, preferably 1 to 20, more preferably 1 to 10, and even more preferably 1 to 5. If n is less than 1, there is a risk of high monomer residue and reduced heat resistance. If n is greater than 20, there is a risk of insufficient fluidity. n can be determined by GPC analysis, and may be calculated from the area % of each peak or from the number-average molecular weight (Mn).

[0016] The epoxy resin of this embodiment can be obtained by reacting a phenol resin, which is obtained by reacting a compound represented by the following formula (a) with a compound represented by the following formula (b), with an epihalohydrin.

[0017] [ka]

[0018] In equation (a) above, R and k have the same meanings as in equation (1) above.

[0019] As for the compound represented by formula (a) above, it is preferable that the compound has alkyl groups at the 2nd and 5th positions (or 3rd and 6th positions) relative to the phenolic hydroxyl group. By introducing hydrocarbon groups at these substitution positions, it is possible to obtain phenolic resins with a narrow molecular weight distribution and epoxy resins derived therefrom. The compound is not particularly limited as long as it has alkyl groups at the 2nd and 5th positions (or 3rd and 6th positions) relative to the phenolic hydroxyl group, but preferred compounds include, for example, 3-methyl-6-t-butylphenol, thymol, carvacrol, 2,5-dimethylphenol, and the like.

[0020] The compound represented by formula (b) above has a hydroxyl group at the ortho position of the aldehyde group, which, after being converted into a phenol resin or epoxy resin, causes steric hindrance, resulting in a high modulus of elasticity and low water absorption of the cured product.

[0021] The reaction between the compound represented by formula (a) and the compound represented by formula (b) may be synthesized using any known method, for example, a reaction in a solvent in the presence of an acid catalyst.

[0022] The compound of formula (a) above is preferably charged in an amount of 1.1 to 8 times the molar amount of the compound of formula (b) above, more preferably 1.25 to 6 times the molar amount, and even more preferably 1.5 to 4 times the molar amount. If the amount is less than 1.1 times the molar amount, washing with water becomes difficult due to the high molecular weight, and the fluidity of the resin may decrease significantly. If the amount exceeds 8 times the molar amount, the yield produced in one batch decreases significantly, and it is also undesirable from the standpoint of increasing waste. In the reaction, hydrochloric acid, phosphoric acid, sulfuric acid, formic acid, p-toluenesulfonic acid, methanesulfonic acid, as well as Lewis acids such as aluminum chloride and zinc chloride, solid acids such as activated clay, acid clay, white carbon, zeolite, silica alumina, and acid ion exchange resins can be used as acid catalysts. These may be used alone or in combination of two or more. The amount of catalyst used is 0.01 to 25% by weight, preferably 0.1 to 15% by weight, relative to the total weight of the reaction substrates, phenols (compound of formula (a) above) and salicylaldehyde (compound of formula (b) above). Using too much catalyst may make stirring during the synthesis reaction difficult and is undesirable as it increases unnecessary waste. Examples of solvents that can be used include non-water-soluble solvents such as aromatic solvents like toluene and xylene, aliphatic solvents like cyclohexane and n-hexane, ethers like diethyl ether and diisopropyl ether, ester solvents like ethyl acetate and butyl acetate, ketone solvents like methyl isobutyl ketone and cyclopentanone, as well as alcohol solvents like methanol, ethanol, and isopropanol, but are not limited to these, and two or more may be used in combination. In addition, aprotic polar solvents may be used in combination with the aforementioned non-water-soluble solvents. Examples include dimethyl sulfone, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, 1,3-dimethyl-2-imidazolidinone, and N-methylpyrrolidone, and two or more may be used in combination. The reaction temperature is preferably 20 to 180°C, more preferably 40 to 160°C, and even more preferably 50 to 130°C. If the reaction temperature is too high, the methine structure of the trisphenolmethane structure may decompose, and if the reaction temperature is too low, the reaction may not proceed sufficiently.After the reaction is complete, the acidic catalyst may be neutralized with an alkaline aqueous solution, the solvent may be recovered, and the target phenol resin may be obtained together with the neutralized salt. Alternatively, an insoluble organic solvent may be added to the oil layer, and the wastewater may be washed repeatedly until it becomes neutral, after which the solvent may be removed under heated reduced pressure to obtain the target phenol resin. When activated clay or ion exchange resin is used, after the reaction is complete, the reaction solution is filtered to remove the catalyst, the solvent is recovered, and the target phenol resin is obtained. The amount of monomer remaining in the compound represented by formula (a) above is preferably 0.01 to 10% by weight, preferably 0.05 to 7.5% by weight, and preferably 0.1 to 5% by weight. This monomer amount affects the amount of low molecular weight remaining in the epoxy resin, and this amount affects the heat resistance, etc.

[0023] The phenol resin obtained by reacting the compound represented by formula (a) above with the compound represented by formula (b) above preferably contains 75 to 95 area percent of the compound represented by formula (c) below in differential refractometer detection in gel permeation chromatography analysis. If the content of formula (c) below is less than 75 area percent, the obtained phenol resin, the epoxy resin made from it, and the curable resin composition containing them may not have sufficient fluidity. If it exceeds 95 area percent, the obtained phenol resin, the epoxy resin made from it, and the curable resin composition containing them may not have sufficient heat resistance, and the crystallinity may be high, resulting in reduced solvent solubility.

[0024] [ka]

[0025] In equation (c) above, R and k have the same meanings as in equation (1) above.

[0026] The number-average molecular weight (Mn) of the phenol resin obtained by reacting the compound represented by formula (a) above with the compound represented by formula (b) above is preferably 300 to 1500, more preferably 325 to 1000, and even more preferably 350 to 800. If the number-average molecular weight is less than 300, the heat resistance may decrease due to residual raw materials, etc. If the number-average molecular weight exceeds 1500, the fluidity may decrease due to the increased molecular weight.

[0027] The weight-average molecular weight (Mw) of the phenol resin obtained by reacting the compound represented by formula (a) above with the compound represented by formula (b) above is preferably 300 to 1500, more preferably 325 to 1000, and even more preferably 350 to 800. If the weight-average molecular weight is less than 300, the heat resistance may decrease due to residual raw materials, etc. If the weight-average molecular weight is greater than 1500, the fluidity may decrease due to the increased molecular weight.

[0028] The hydroxyl group equivalent of the phenol resin obtained by reacting the compound represented by formula (a) with the compound represented by formula (b) is preferably 100 to 200 g / eq., more preferably 110 to 180 g / eq., and even more preferably 120 to 160 g / eq. The above hydroxyl group equivalent may be calculated from the area % obtained by gel permeation chromatography (GPC) analysis, or it may be measured by titration. When measuring by titration, for example, the sample is acetylated in a pyridine solution with acetic anhydride, the remaining acid anhydride is decomposed with water after acetylation is complete, and the amount of free acetic acid is measured by titrating with a 0.5 N KOH ethanol solution using a potentiometric titrator, and the hydroxyl group equivalent can be determined from the result.

[0029] The content of the polymer component of the compound represented by formula (c) above is preferably 1 to 25 area%, and more preferably 3 to 15 area%, as determined by gel permeation chromatography analysis (detection by differential refractometer). If it exceeds 25 area%, fluidity may decrease, and if it falls below 3 area%, solvent solubility and heat resistance may decrease.

[0030] A typical structure of the phenol resin obtained by reacting the compound represented by formula (a) above with the compound represented by formula (b) above can be represented as shown in formula (c-1) below.

[0031] [ka]

[0032] In equation (c-1) above, R, k, and n have the same meanings as in equation (1) above.

[0033] The epoxy resin of this embodiment can be obtained by reacting a phenol resin, which is obtained by reacting a compound represented by formula (a) with a compound represented by formula (b), with an epihalohydrin. For example, it can be obtained by adding or ring-closing the phenol resin of this embodiment with the epihalohydrin in the presence of a solvent and a catalyst. The amount of epihalohydrin used is usually 1.0 to 20.0 moles, preferably 1.5 to 10.0 moles, per mole of phenolic hydroxyl groups of the phenol resin.

[0034] Examples of alkali metal hydroxides that can be used in the epoxidation reaction include sodium hydroxide and potassium hydroxide. The alkali metal hydroxide may be used in solid form or as an aqueous solution. When using an aqueous solution, the aqueous solution of the alkali metal hydroxide may be continuously added to the reaction system, and water and epihalohydrin may be continuously distilled off under reduced pressure or normal pressure, followed by liquid-liquid separation to remove the water and continuously returning the epihalohydrin to the reaction system. The amount of alkali metal hydroxide used is usually 0.9 to 2.5 moles per mole of phenolic hydroxyl groups of the phenolic resin, preferably 0.95 to 1.5 moles. If the amount of alkali metal hydroxide used is too small, the reaction will not proceed sufficiently. On the other hand, excessive use of alkali metal hydroxide exceeding 2.5 moles per mole of phenolic hydroxyl groups of the phenolic resin will result in the generation of unnecessary waste by-products.

[0035] To accelerate the above reaction, quaternary ammonium salts such as tetramethylammonium chloride, tetramethylammonium bromide, and trimethylbenzylammonium chloride may be added as catalysts. The amount of quaternary ammonium salt used is usually 0.1 to 15 g, preferably 0.2 to 10 g, per mole of phenolic hydroxyl groups in the phenolic resin. If the amount used is too small, a sufficient reaction-accelerating effect will not be obtained, and if the amount used is too large, the amount of quaternary ammonium salt remaining in the epoxy resin will increase, which may cause deterioration of electrical reliability.

[0036] During the epoxidation reaction, it is preferable to add alcohols such as methanol, ethanol, and isopropyl alcohol, or aprotic polar solvents such as dimethyl sulfone, dimethyl sulfoxide, tetrahydrofuran, and dioxane to facilitate the reaction. When alcohols are used, the amount used is usually 2 to 50% by weight, preferably 4 to 20% by weight, relative to the amount of epihalohydrin. When aprotic polar solvents are used, the amount used is usually 5 to 100% by weight, preferably 10 to 80% by weight, relative to the amount of epihalohydrin. The reaction temperature is usually 30 to 90°C, preferably 35 to 80°C. The reaction time is usually 0.5 to 100 hours, preferably 1 to 30 hours.

[0037] After the reaction is complete, the reactants are washed with water, or heated under reduced pressure without washing, to remove epihalohydrins, solvents, etc. Furthermore, to obtain an epoxy resin with fewer hydrolyzable halogens, the recovered epoxy resin can be dissolved in a solvent such as toluene or methyl isobutyl ketone, and an aqueous solution of alkali metal hydroxide such as sodium hydroxide or potassium hydroxide can be added to carry out the reaction and ensure ring closure. In this case, the amount of alkali metal hydroxide used is usually 0.01 to 0.3 moles, preferably 0.05 to 0.2 moles, per mole of phenolic hydroxyl groups of the phenol resin used for glycidylation. The reaction temperature is usually 50 to 120°C, and the reaction time is usually 0.5 to 24 hours. After the reaction is complete, the generated salt is removed by filtration, washing with water, etc., and the solvent is further removed by distillation under reduced pressure, thereby obtaining the epoxy resin of this embodiment.

[0038] The softening point of the epoxy resin in this embodiment is preferably 40 to 150°C, more preferably 45 to 125°C, and even more preferably 50 to 100°C. If the softening point is higher than 150°C, solvent tends to remain when the resin is removed, and voids are likely to form during curing. There are also significant production challenges, such as a tendency to foam during solvent removal. On the other hand, if the softening point is below 40°C, it negatively affects heat resistance and thermal decomposition properties. Furthermore, the epoxy equivalent is preferably 150 to 300 g / eq., more preferably 160 to 275 g / eq., and even more preferably 170 to 250 g / eq. If the epoxy equivalent is less than 150 g / eq., there is a possibility of residual epichlorohydrin and a large amount of impurity epoxidized products remaining, which may lead to deterioration of properties. If it exceeds 300 g / eq., a decrease in heat resistance becomes a problem. The ICI viscosity of the epoxy resin in this embodiment at 150°C is preferably 0.01 to 0.5 Pa·s, more preferably 0.01 to 0.4 Pa·s, and even more preferably 0.01 to 0.3 Pa·s. If the ICI viscosity at 150°C exceeds 0.5 Pa·s, it is difficult to obtain sufficient fluidity. In this embodiment, fluidity is improved by controlling the gel time during curing by utilizing the steric hindrance of the alkyl group derived from the compound of formula (a) and the orientation of the hydroxyl group derived from the compound of formula (b) (having a hydroxyl group at the ortho position of the aldehyde). If the gel time during curing is too fast, the resin will not flow properly during molding.

[0039] The epoxy resin of this embodiment contains 75 to 95 area percent of the compound represented by the following formula (d) as detected by a differential refractometer in gel permeation chromatography analysis. If the content of the following formula (d) is less than 75 area percent, the epoxy resin of this embodiment and the curable resin composition containing them may not be able to obtain sufficient fluidity. If it exceeds 95 area percent, the epoxy resin of this embodiment and the curable resin composition containing them may not be able to obtain sufficient heat resistance, and the crystallinity may be high, resulting in reduced solvent solubility.

[0040] [ka]

[0041] In equation (c) above, R and k have the same meanings as in equation (1) above.

[0042] The curable resin composition of this embodiment contains a reactive compound. The reactive compound does not include the epoxy resin represented by formula (1) above.

[0043] Examples of the above-mentioned reactive compounds include epoxy resins other than the epoxy resin represented by formula (1) above, amine compounds, amide compounds, acid anhydride compounds, phenolic resins, active ester compounds, carboxylic acid compounds, maleimide compounds, cyanate compounds, isocyanate compounds, polyphenylene ether compounds, compounds having ethylenically unsaturated bonds, polyamide compounds, polyimide compounds, allyl compounds, polybutadiene and its modified products, polystyrene and its modified products, polyethylene and its modified products, benzoxazine compounds, etc. These may be used individually or in combination of multiple types. Among these compounds, it is preferable to include polyphenylene ether compounds, compounds having ethylenically unsaturated bonds, cyanate ester resins, polybutadiene and its modified products, polystyrene and its modified products, etc., in order to balance heat resistance, adhesion, and dielectric properties. By including these compounds, it is possible to improve the brittleness of the cured product and enhance adhesion to metals, and to suppress cracks in the package during reliability tests such as solder reflow and thermal cycling. The total amount of the above compounds used is preferably 10 times or less by mass, more preferably 5 times or less by mass, and most preferably 3 times or less by mass, relative to the compound of this embodiment, unless otherwise specified. Furthermore, the preferred lower limit is 0.1 times or more by mass, more preferably 0.25 times or more by mass, and even more preferably 0.5 times or more by mass. Within this range, the effects of each added compound can be added while utilizing the heat-resistant effect of the compound of this embodiment. Examples of these components can be used as shown below.

[0044] [Epoxy resins other than those represented by formula (1)] Examples of preferred epoxy resins other than the epoxy resin represented by formula (1) above are given below, but are not limited to these. The epoxy resin may be liquid or solid, and may be used alone or in combination of multiple types.

[0045] Examples of liquid epoxy resins include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AF type epoxy resin, bisphenol E type epoxy resin, bisphenol S type epoxy resin, bisphenol M type epoxy resin (4,4'-(1,3-phenylenediisopridiene)bisphenol type epoxy resin), bisphenol P type epoxy resin (4,4'-(1,4-phenylenediisopridiene)bisphenol type epoxy resin), bisphenol Z type epoxy resin (4,4'-cyclohexydienebisphenol type epoxy resin), naphthalene type epoxy resin, glycidyl ester type epoxy resin, glycidylamine type epoxy resin, phenol novolac type epoxy resin, alicyclic epoxy resin having an ester skeleton, cyclohexane type epoxy resin, cyclohexanedimethanol type epoxy resin, oxazolidone ring skeleton-containing epoxy resin, and epoxy resin having a butadiene structure.Specific examples include "RE310S", "RE410S" (both manufactured by Nippon Kayaku Co., Ltd., bisphenol A type epoxy resin), "RE303S", "RE304S", "RE403S", "RE404S" (all manufactured by Nippon Kayaku Co., Ltd., bisphenol F type epoxy resin), "HP4032", "HP4032D", "HP4032SS" (all manufactured by DIC Corporation, naphthalene type epoxy resin), "828US", "jER828EL", "825", "828EL" (all manufactured by Mitsubishi Chemical Corporation, bisphenol A type epoxy resin), "jE807", "1750" (both manufactured by Mitsubishi Chemical Corporation, bisphenol F type epoxy resin), "jER152" (manufactured by Mitsubishi Chemical Corporation, phenol novolac type epoxy resin), "jER604", "jER630", "630LSD" (and others). Examples include: (above, manufactured by Mitsubishi Chemical Corporation, glycidylamine type epoxy resin), "GAN", "GOT" (both manufactured by Nippon Kayaku Co., Ltd., glycidylamine type epoxy resin), "TSR-400" (manufactured by DIC Corporation, oxazolidone ring-containing epoxy resin), "ZX1059" (manufactured by Nippon Steel & Sumitomo Metal Chemical Co., Ltd., a mixture of bisphenol A type epoxy resin and bisphenol F type epoxy resin), "EX-721" (manufactured by Nagase ChemteX Corporation, glycidyl ester type epoxy resin), "Celoxide 2021P" (manufactured by Daicel Corporation, alicyclic epoxy resin with an ester skeleton), "PB-3600" (manufactured by Daicel Corporation, epoxy resin with a butadiene structure), "ZX1658", "ZX1658GS" (both manufactured by Nippon Steel & Sumitomo Metal Chemical Co., Ltd., liquid 1,4-glycidylcyclohexane type epoxy resin). These may be used individually or in combination of two or more types.

[0046] Examples of solid epoxy resins include bixylenol-type epoxy resin, naphthol-type epoxy resin, naphthol-type tetrafunctional epoxy resin, cresol novolac-type epoxy resin, dicyclopentadiene-type epoxy resin, trisphenol-type epoxy resin, naphthol-type epoxy resin, biphenyl-type epoxy resin, naphthylene ether-type epoxy resin, anthracene-type epoxy resin, bisphenol A-type epoxy resin, bisphenol AF-type epoxy resin, tetraphenylethane-type epoxy resin, imide-skeleton-type epoxy resin, isocyanur-type epoxy resin, and the like. Specific examples include "HP4032H", "HP-4770" (manufactured by DIC Corporation, naphthalene-type epoxy resin), "HP-4750" (manufactured by DIC Corporation, naphthalene-type trifunctional epoxy resin), "HP-4700", "HP-4710" (both manufactured by DIC Corporation, naphthalene-type tetrafunctional epoxy resin), "N-690" (manufactured by DIC Corporation, cresol novolac-type epoxy resin), and "N-695" (manufactured by DIC Corporation, cresol novolac). (Type epoxy resin), "N-655-EXP-S" (manufactured by DIC Corporation, cresol novolac type epoxy resin), "HP-7200" (manufactured by DIC Corporation, dicyclopentadiene type epoxy resin), "HP-7200", "HP-7200HH", "HP-7200H" (all manufactured by DIC Corporation, dicyclopentadiene type epoxy resin), "EXA-7311", "EXA-7311-G3", "EXA-7311-G4", "E XA-7311-G4S, HP-6000 (both manufactured by DIC Corporation, naphthylene ether type epoxy resin), EPPN-502H, FAE-2500 (both manufactured by Nippon Kayaku Co., Ltd., trisphenol type epoxy resin), NC-7000L, NC-7300 (both manufactured by Nippon Kayaku Co., Ltd., naphthol-cresol novolac type epoxy resin), NC-3000H, NC-3000, NC-3000L "NC-3100" (all manufactured by Nippon Kayaku Co., Ltd., biphenyl aralkyl type epoxy resin), "XD-1000-2L", "XD-1000-L", "XD-1000-H" (all manufactured by Nippon Kayaku Co., Ltd., dicyclopentadiene type epoxy resin), "WHR-991S" (imide skeleton type epoxy resin), "ESN475V" (manufactured by Nippon Steel & Sumitomo Metal Chemical Co., Ltd., naphthol type epoxy resin), "ESN485" (manufactured by Nippon Steel & Sumitomo Metal Chemical Co., Ltd.,Naphthol novolac type epoxy resin), "YX-4000H", "YX-4000", "YL6121" (all manufactured by Mitsubishi Chemical Corporation, biphenyl type epoxy resin), "YX-4000HK" (manufactured by Mitsubishi Chemical Corporation, bixylenol type epoxy resin), "YX-8800" (manufactured by Mitsubishi Chemical Corporation, anthracene type epoxy resin), "PG-100", "CG-500" (manufactured by Osaka Gas Chemical Co., Ltd., fluorene-based epoxy resin), "YX7760" (manufactured by Mitsubishi Chemical Corporation, Examples include bisphenol AF type epoxy resin, "YL-7800" (manufactured by Mitsubishi Chemical Corporation, fluorene type epoxy resin), "jER1010" (manufactured by Mitsubishi Chemical Corporation, solid bisphenol A type epoxy resin), "jER1031S" (manufactured by Mitsubishi Chemical Corporation, tetraphenylethane type epoxy resin), CNE-195LL (manufactured by Changchun Artificial Resin Co., Ltd., orthocresol novolac type epoxy resin), and "TEPIC-S" (manufactured by Nissan Chemical Corporation, isocyanurate type epoxy resin). These may be used individually or in combination of two or more types.

[0047] [Amine compounds] Examples of the above amine compounds include o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 4,4'-methylenebis(2-ethyl-6-methylaniline), 4,4'-diaminodiphenylsulfone, 3,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, 2,2'-diaminodiphenylsulfone, diethyltoluenediamine, dimethylthiotoluenediamine, diaminodiphenylmethane, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, 3,3'-diethyl-4, 4'-Diaminodiphenylmethane, 4,4'-Diamino-3,3'-Diethyl-5,5'-Dimethyldiphenylmethane, 4,4'-Diamino-3,3',5,5'-Tetramethyldiphenylmethane, 4,4'-Diamino-3,3',5,5'-Tetraethyldiphenylmethane, 4,4'-Diamino-3,3',5,5'-Tetraisopropyldiphenylmethane, 3,3'-Diisopropyl-4,4'-Diaminodiphenylmethane, 3,3'-Di-t-Butyl-4,4'-Diaminodiphenylmethane, 3,3'-Diisopropyl-5,5 '-dimethyl-4,4'-diaminodiphenylmethane, 3,3'-di-t-butyl-5,5'-dimethyl-4,4'-diaminodiphenylmethane, 3,3'-diisopropyl-5,5'-diethyl-4,4'-diaminodiphenylmethane, 3,3'-di-t-butyl-5,5'-diethyl-4,4'-diaminodiphenylmethane, 3,3'-di-t-butyl-5,5'-diisopropyl-4,4'-diaminodiphenylmethane, 3,3',5,5'-tetra-t-butyl-4,4'-diaminodiphenylmethane, 4,4'-methylene Bis(N-methylaniline), bis(aminophenyl)fluorene, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 2,2'-bis[4-(4-aminophenoxy)phenyl]propane, bis[4-(4-aminophenoxy)phenyl]sulfone, 1,3'-bis(4-aminophenoxy)benzene, 1,4'-bis(4-aminophenoxy)benzene, 1,4'-bis(4-aminophenoxy)biphenyl, 4,4'-(1,3-phenylenedisopropylidene)bisaniline, 4,4'-(1,Examples of aromatic amine compounds include, but are not limited to, 4-phenylenediisopropylidene)bisaniline, naphthalenediamine, benzidine, dimethylbenzidine, aromatic amine compounds described in Synthesis Examples 1 and 2 of International Publication No. 2017 / 170551, 1,3-bis(aminomethyl)cyclohexane, isophoronediamine, 4,4'-methylenebis(cyclohexylamine), norbornanediamine, ethylenediamine (EDA), propanediamine (PDA), tetramethylenediamine (TMDA), pentamethylenediamine (PMDA), hexamethylenediamine (HMDA), diethylenetriamine (DETA), triethylenetetramine (TETA), metaxylylenediamine (MXDA), dimer amine, and other aliphatic amines. They can be suitably used depending on the properties to be imparted to the composition. It is preferable to use aromatic amines to ensure pot life, and it is preferable to use aliphatic amines when immediate curing is desired. By using an amine-based compound containing a bifunctional component as the main component as a curing agent, a highly linear network can be constructed during the curing reaction, resulting in particularly excellent toughness.

[0048] [Amide compounds] Examples of the above-mentioned amide compounds include dicyandiamide (DICY).

[0049] [Acid anhydride compound] Examples of the above-mentioned acid anhydride compounds include phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, and benzophenonetetracarboxylic acid. Specific examples include "KAYAHARD MCD" (manufactured by Nippon Kayaku Co., Ltd.), "Licacid MH-700" (manufactured by Shin Nippon Rika Co., Ltd., 4-methylhexahydrophthalic anhydride), "Licacid TH" (manufactured by Shin Nippon Rika Co., Ltd., tetrahydrophthalic anhydride), and "Licacid HH" (manufactured by Shin Nippon Rika Co., Ltd., hexahydrophthalic anhydride).

[0050] [Phenolic resin] Examples of the above-mentioned phenolic resins include polyhydric phenols (bisphenol A, bisphenol F, bisphenol S, bisphenol M, bisphenol AD, biphenol, dihydroxynaphthalene, fluorenebisphenol, terpene diphenol, 4,4'-dihydroxybiphenyl, 2,2'-dihydroxybiphenyl, 3,3',5,5'-tetramethyl-(1,1'-biphenyl)-4,4'-diol, dihydroxybenzene, naphthalenediol, tris-(4-hydroxyphenyl)methane, and 1,1,2,2-teto Lax(4-hydroxyphenyl)ethane, etc.), the aforementioned polyhydric phenols or phenols (phenol, alkyl-substituted phenol, aromatic-substituted phenol, naphthol, alkyl-substituted naphthol, dihydroxybenzene, alkyl-substituted dihydroxybenzene, dihydroxynaphthalene, etc.) and various aldehydes (formaldehyde, acetaldehyde, alkylaldehyde, benzaldehyde, alkyl-substituted benzaldehyde, hydroxybenzaldehyde, naphthaldehyde, glutaraldehyde, phthalaldehyde, crotonaldehyde, Polycondensates of cinnamaldehyde, etc., or polymers of the aforementioned polyhydric phenols or phenols with various diene compounds (dicyclopentadiene, terpenes, vinylcyclohexene, norbornadiene, vinylnorbornene, tetrahydroindene, divinylbenzene, divinylbiphenyl, disopropenylbiphenyl, butadiene, isoprene, etc.), or polycondensates of the aforementioned polyhydric phenols or phenols with ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone, benzophenone, etc.) Examples include polycondensates of the aforementioned polyhydric phenols or phenols with aromatic dimethanols (benzenedimethanol, biphenyldimethanol, etc.), polycondensates of the aforementioned polyhydric phenols or phenols with aromatic dichloromethyls (α,α'-dichloroxylene, bischloromethylbiphenyl, etc.), or polycondensates of the aforementioned polyhydric phenols or phenols with aromatic bisalkoxymethyls (bismethoxymethylbenzene, bismethoxymethylbiphenyl, bisphenoxymethylbiphenyl, etc.).Specific examples include "MEH-7700," "MEH-7810," "MEH-7851," and "PN" (all manufactured by Meiwa Kasei Co., Ltd., phenol novolac resins), and "GPH-65" and "GPH-103" (both manufactured by Nippon Kayaku Co., Ltd., biphenyl aralkyl type phenol resins).

[0051] [Activated ester compounds] The above-mentioned active ester compounds refer to compounds that contain at least one ester bond in their structure, and on both sides of the ester bond, an aliphatic chain, an aliphatic ring, or an aromatic ring is bonded. Examples of active ester compounds include compounds having two or more highly reactive ester groups in one molecule, such as phenol esters, thiophenol esters, N-hydroxyamine esters, and esters of heterocyclic hydroxy compounds. These are obtained by a condensation reaction between at least one compound of a carboxylic acid compound, an acid chloride, or a thiocarboxylic acid compound and at least one compound of a hydroxy compound or a thiol compound. In particular, from the viewpoint of improving heat resistance, it is preferable that they be obtained from a carboxylic acid compound or an acid chloride and a hydroxy compound, and phenol compounds or naphthol compounds are preferred as the hydroxy compound. Active ester compounds may be used alone or in combination of two or more.

[0052] Examples of the carboxylic acid compounds mentioned above include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, and pyromellitic acid.

[0053] Examples of the above-mentioned acid chlorides include acetyl chloride, acrylate chloride, methacrylate chloride, malonyl chloride, succinate dichloride, diglycolyl chloride, glutarate dichloride, suberic acid dichloride, sebacate dichloride, adipic acid dichloride, dodecanediol dichloride, azera oil chloride, 2,5-franzicarbonyl dichloride, phthaloyl chloride, isophthaloyl chloride, terephthaloyl chloride, trimesic acid chloride, bis(4-chlorocarbonylphenyl) ether, 4,4'-diphenyldicarbonyl chloride, and 4,4'-azodibenzoyl dichloride.

[0054] Examples of the above-mentioned phenol compounds and naphthol compounds include hydroquinone, resorcinol, bisphenol A, bisphenol F, bisphenol S, phenolphthalein, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m-cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, benzenetriol, dicyclopentadiene-type diphenol compounds, phenol novolac, and phenol resins described later. Here, "dicyclopentadiene-type diphenol compound" refers to a diphenol compound obtained by the condensation of two molecules of phenol with one molecule of dicyclopentadiene.

[0055] Preferred examples of active ester compounds include active ester compounds containing a dicyclopentadiene-type diphenol structure, active ester compounds containing a naphthalene structure, active ester compounds containing an acetylated phenol novolac, active ester compounds containing a benzoylated phenol novolac, the compounds described in Example 2 of International Publication No. 2020 / 095829, and the compounds disclosed in International Publication No. 2020 / 059625. Among these, active ester compounds containing a naphthalene structure and active ester compounds containing a dicyclopentadiene-type diphenol structure are more preferred. The dicyclopentadiene-type diphenol structure represents a divalent structural unit consisting of phenylene-dicyclopentylene-phenylene.

[0056] Commercially available active ester compounds include, for example, "EXB9451," "EXB9460," "EXB9460S," "HPC-8000-65T," "HPC-8000H-65TM," "EXB-8000L-65TM," and "EXB-8150-65T" (manufactured by DIC Corporation) as active ester compounds containing a dicyclopentadiene-type diphenol structure; "EXB9416-70BK" (manufactured by DIC Corporation) as an active ester compound containing a naphthalene structure; "DC808" (manufactured by Mitsubishi Chemical Corporation) as an active ester compound containing an acetylated phenol novolac; "YLH1026," "YLH1030," and "YLH1048" (manufactured by Mitsubishi Chemical Corporation) as active ester compounds containing a benzoylated phenol novolac; "EXB-9050L-62M" (manufactured by DIC Corporation) as a phosphorus atom-containing active ester curing agent; and "Unifiner" as an active ester compound containing a bisphenol A structure. Examples include "W-575".

[0057] [Carboxylic acid compounds] Examples of the carboxylic acid compounds mentioned above include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, oxalic acid, malonic acid, succicic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, undecanediic acid, dodecanediic acid, phthalic acid, isophthalic acid, terephthalic acid, pyromellitic acid, 5-hydroxyisophthalic acid, 2-chloroterephthalic acid, 2-methylterephthalic acid, 5-methylisophthalic acid, 5-sodium sulfoisophthalic acid, hexahydroterephthalic acid, hexahydroisophthalic acid, cyclohexanedicarboxylic acid, biphenyldicarboxylic acid, naphthalenedicarboxylic acid, benzophenonedicarboxylic acid, francicarboxylic acid, 4,4'-dicarboxydiphenyl ether, and 4,4'-dicarboxydiphenyl sulfide. A commercially available product is G4-142MHR (manufactured by Nippon Kayaku Co., Ltd.).

[0058] [Maleimide compounds] Examples of the above maleimide compounds include phenylmaleimide, 4,4'-diphenylmethanebismaleimide, polyphenylmethanemaleimide, m-phenylenebismaleimide, 2,2'-bis[4-(4-maleimidophenoxy)phenyl]propane, 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethanebismaleimide, 4-methyl-1,3-phenylenebismaleimide, 4,4'-diphenyletherbismaleimide, 4,4'-diphenylsulfonebismaleimide, 1,3-bis(3-maleimidophenoxy)benzene, 1,3-bis(4-maleimidophenoxy)benzene, and Zyloc-type maleimide compounds (anilix). Maleimide (manufactured by Mitsui Chemicals Fine Co., Ltd.), biphenylaralkyl type maleimide compound (solidified by solvent distillation under reduced pressure of a resin solution containing the maleimide compound (M2) described in Example 4 of Japanese Patent Publication No. 2009-001783), bisaminocumylbenzene type maleimide (maleimide compound described in International Publication No. 2020 / 054601), maleimide compound having an indan structure described in Japanese Patent No. 6629692 or International Publication No. 2020 / 217679, polymaleimide derived from aromatic vinyl compounds and anilines described in Japanese Patent Publication No. 2023-007239, MATERIAL STAGE Vol. 18, No. 12 2019 "~Continued Epoxy Resin CAS Number Story~ Curing Agent CAS Number Memo No. 31 Bismaleimide (1)" and MATERIAL STAGE Vol. 19, No. 2 2019 Examples include maleimide compounds described in "~Continued Story of Epoxy Resin CAS Numbers~ Memo on CAS Numbers of Hardeners, Part 32: Bismaleimide (2)". Commercially available examples include MIR-3000-70MT (biphenyl aralkyl type maleimide compound, manufactured by Nippon Kayaku Co., Ltd.) and MIZ-001 (manufactured by Nippon Kayaku Co., Ltd.).

[0059] [Cyanate compounds] Cyanate compounds are obtained by reacting phenol compounds with cyanide halides. Specific examples include dicyanatebenzene, tricyanatebenzene, dicyanatenaphthalene, dicyanatebiphenyl, 2,2'-bis(4-cyanatephenyl)propane, bis(4-cyanatephenyl)methane, bis(3,5-dimethyl-4-cyanatephenyl)methane, 2,2'-bis(3,5-dimethyl-4-cyanatephenyl)propane, 2,2'-bis(4-cyanatephenyl)ethane, 2,2'-bis(4-cyanatephenyl)hexafluoropropane, bis(4-cyanatephenyl)sulfone, bis(4-cyanatephenyl)thioether, phenol novolac cyanate, and compounds obtained by converting the hydroxyl groups of phenol-dicyclopentadiene cocondensates to cyanate groups. A commercially available example is SYTESTER TA (manufactured by Mitsubishi Gas Chemical Company, a bisphenol A type cyanate resin). These can be used individually or in combination. Furthermore, the cyanate compound whose synthesis method is described in Japanese Patent Publication No. 2005-264154 is particularly preferred as a cyanate compound because it has excellent low hygroscopicity, flame retardancy, and dielectric properties. The cyanate compound may also contain catalysts such as zinc naphthenate, cobalt naphthenate, copper naphthenate, lead naphthenate, zinc octoate, tin octoate, lead acetylacetonate, or dibutyltin maleate to trimerize the cyanate group as needed and form a sym-triazine ring.

[0060] It is preferable to use 0.0001 to 0.10 parts by mass, preferably 0.00015 to 0.0015 parts by mass, of the catalyst per 100 parts by mass of the cyanate compound and the curable resin composition.

[0061] [Isocyanate compounds] An isocyanate compound is a compound that has two or more isocyanate groups in its molecule. Examples of isocyanate compounds include, but are not limited to, aromatic diisocyanates such as p-phenylenediisocyanate, m-phenylenediisocyanate, p-xylenediisocyanate, m-xylenediisocyanate, 2,4-tolylenediisocyanate, 2,6-tolylenediisocyanate, 4,4'-diphenylmethanediisocyanate, and naphthalenediisocyanate; aliphatic or alicyclic diisocyanates such as isophorone diisocyanate, hexamethylenediisocyanate, 4,4'-dicyclohexylmethanediisocyanate, hydrogenated xylenediisocyanate, norbornene diisocyanate, and lysine diisocyanate; biuret compounds of one or more isocyanate monomers; or isocyanate compounds obtained by trimerizing the above diisocyanate compounds; and polyisocyanates obtained by urethane reaction between the above isocyanate compounds and polyol compounds. Furthermore, these can be used individually or in combination.

[0062] [Polyphenylene ether compounds] From the viewpoint of heat resistance and electrical properties, the polyphenylene ether compound is preferably a polyphenylene ether compound having an ethylenically unsaturated bond, and more preferably a polyphenylene ether compound having an acrylic group, a methacrylic group, or a styrene structure. Commercially available products include SA-9000 (manufactured by SABIC, a polyphenylene ether compound having a methacrylic group), OPE-2St 1200, and OPE-2st 2200 (both manufactured by Mitsubishi Gas Chemical Company, polyphenylene ether compounds having a styrene structure). The number-average molecular weight (Mn) of the polyphenylene ether compound is preferably 500 to 5000, more preferably 2000 to 5000, and even more preferably 2000 to 4000. If the number-average molecular weight is less than 500, the heat resistance of the cured product tends not to be sufficient. If the number-average molecular weight is greater than 5000, the melt viscosity increases, and sufficient fluidity cannot be obtained, which tends to lead to molding defects. Furthermore, the reactivity decreases, requiring a long time for the curing reaction, increasing the amount of unreacted material that is not incorporated into the curing system, lowering the glass transition temperature of the cured product, and tending to reduce the heat resistance of the cured product. If the number-average molecular weight of the polyphenylene ether compound is between 500 and 5000, it is possible to achieve excellent heat resistance and moldability while maintaining excellent dielectric properties. Specifically, the number-average molecular weight can be measured using methods such as gel permeation chromatography.

[0063] Polyphenylene ether compounds may be obtained by polymerization reactions, or by redistributing high molecular weight polyphenylene ether compounds with a number average molecular weight of approximately 10,000 to 30,000. Alternatively, these may be used as raw materials and reacted with compounds having ethylenically unsaturated bonds, such as methacrylate chloride, acrylate chloride, and chloromethylstyrene, to impart radical polymerizability. Polyphenylene ether compounds obtained by redistribution reactions can be obtained, for example, by heating a high molecular weight polyphenylene ether compound in a solvent such as toluene in the presence of a phenolic compound and a radical initiator to induce a redistribution reaction. Polyphenylene ether compounds obtained by such redistribution reactions are preferable because they maintain even higher heat resistance due to having hydroxyl groups derived from phenolic compounds that contribute to curing at both ends of the molecular chain, and because functional groups can be introduced to both ends of the molecular chain even after modification with compounds having ethylenically unsaturated bonds. Furthermore, polyphenylene ether compounds obtained by polymerization reactions are preferable because they exhibit excellent fluidity.

[0064] The molecular weight of polyphenylene ether compounds can be adjusted by adjusting polymerization conditions, etc., in the case of polyphenylene ether compounds obtained by polymerization reactions. In the case of polyphenylene ether compounds obtained by redistribution reactions, the molecular weight of the resulting polyphenylene ether compound can be adjusted by adjusting the conditions of the redistribution reaction, etc. More specifically, this can be done by adjusting the amount of phenolic compound used in the redistribution reaction. That is, the higher the amount of phenolic compound used, the lower the molecular weight of the resulting polyphenylene ether compound. In this case, poly(2,6-dimethyl-1,4-phenylene ether) can be used as the high molecular weight polyphenylene ether compound that undergoes the redistribution reaction. Furthermore, the phenolic compound used in the redistribution reaction is not particularly limited, but polyfunctional phenolic compounds having two or more phenolic hydroxyl groups in the molecule, such as bisphenol A, phenol novolac, and cresol novolac, are preferably used. These may be used individually or in combination of two or more.

[0065] The content of the polyphenylene ether compound is not particularly limited, but is preferably 5 to 1000 parts by mass, and more preferably 10 to 750 parts by mass, per 100 parts by mass of the curable resin composition. When the content of the polyphenylene ether compound is within the above range, it is preferable not only to obtain a cured product that is excellent in heat resistance and the like, but also in that the excellent dielectric properties of the polyphenylene ether compound are fully exhibited.

[0066] [Compounds containing ethylenically unsaturated bonds] A compound containing an ethylenically unsaturated bond is a compound that has one or more ethylenically unsaturated bonds in its molecule that can be polymerized by heat or light, regardless of whether a polymerization initiator is used or not. Examples of compounds containing ethylenically unsaturated bonds include acenaphthylene, indene, styrene, divinylbenzene, reaction products of the phenolic resin and halogenated compounds containing ethylenically unsaturated bonds (chloromethylstyrene, allyl chloride, methallyl chloride, acrylate chloride, methacrylate chloride, etc.), reaction products of ethylenically unsaturated phenols (2-allylphenol, 2-propenylphenol, 4-allylphenol, 4-propenylphenol, eugenol, isoeugenol, etc.) and halogenated compounds (1,4-bis(chloromethyl)benzene, 4,4'-bis(chloromethyl)biphenyl, 4,4'-difluorobenzophenone, 4,4'-dichlorobenzophenone, 4,4'-dibromobenzophenone, cyanuryl chloride, etc.), reaction products of epoxy resins or alcohols and (meth)acrylic acids (acrylic acid, methacrylic acid, etc.), and acid-modified products thereof. Specific examples include poly(arylene ether) polymers (HC-G0037, HC-G0024, HC-G0030, HC-G0038), all manufactured by JSR Corporation. These may contain monomer units containing pyridazine, pyrimidine, or pyrazine groups.), reaction products of fluorenes or indenes with halogenated compounds containing ethylenically unsaturated bonds (chloromethylstyrene, allyl chloride, methyl chloride, acrylate chloride, methacrylate chloride, etc.), compounds described in Japanese Patent No. 6951829, copolymers containing divinylbenzene as a constituent unit (ODV-XET(X3), ODV-XET(X4), ODV-XET(X5), all manufactured by Nippon Steel Chemical & Material Co., Ltd.), styrene, vinyltoluene Examples include, but are not limited to, ethyl vinylbenzene, vinyl naphthalene, vinyl biphenyl, vinyl fluorene, divinylbenzene, divinyl naphthalene, divinyl biphenyl, divinyl fluorene, BVPM (bis(vinylphenyl)methane), BVPE (bis(vinylphenyl)ethane), BVPH (bis(vinylphenyl)hexane), trivinylcyclohexane, thermosetting cycloolefin copolymers (Mitsui Chemicals: GigaFreak, Zeon Corporation: TU-01A), and KAYARAD R-684. These can be used individually or in combination.

[0067] [Polyamide resin] Examples of polyamide resins include reaction products of one or more of diamines, diisocyanates, or oxazolines with dicarboxylic acids, reaction products of diamines and acid chlorides, and ring-opening polymers of lactam compounds. These can be used individually or in combination. Specific examples of each of the above ingredients are given below, but this list is not exhaustive. <Diamine> Ethylenediamine, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decanediamine, undecanediamine, dodecanediamine, tridecanediamine, tetradecanediamine, pentadecanediamine, hexadecanediamine, heptadecanediamine, octadecanediamine, nonadecanediamine, eicosanediamine, 2-methyl-1,5-diaminopentane, 2-methyl 1,8-diaminooctane, dimeramine, cyclohexanediamine, bis-(4-aminocyclohexyl)methane, bis(3-methyl-4-aminocyclohexyl)methane, xylylenediamine, norbornanediamine, isophoronediamine, bisaminomethyltricyclodecane, phenylenediamine, diethyltoluenediamine, naphthalenediamine, diaminodiphenylmethane, bis(4-amino-3,5-dimethylphenyl)methane, bis(4-amino-3,5-diethylphenyl)methane 4,4'-methylenebis-o-toluidine, 4,4'-methylenebis-o-ethylaniline, 4,4'-methylenebis-2-ethyl-6-methylaniline, 4,4'-methylenebis-2,6-diisopropylaniline, 4,4-ethylenedianiline, diaminodiphenylsulfone, diaminodiphenyl ether, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 4,4-bis(4-aminophenoxy)biphenyl, 2,2-bis[4-(4-amino [phenoxy)phenyl]propane, bis[4-(4-aminophenoxy)phenyl]sulfone, 2,2-bis(3-amino-4-hydroxyphenyl)propane, 2,2-bis(4-aminophenyl)hexafluoropropane, 4,4'-(1,3-phenylenediisopropylidene)bisaniline, 4,4'-(1,4-phenylenediisopropylidene)bisaniline, 9,9-bis(4-aminophenyl)fluorene, 2,7-diaminofluorene, aminobenzylamine, diaminobenzophenone, etc. <Diisocyanate> Benzene diisocyanate, toluene diisocyanate, 1,3-bis(isocyanatomethyl)benzene, 1,3-bis(isocyanatomethyl)cyclohexane, bis(4-isocyanatophenyl)methane, isophorone diisocyanate, 1,3-bis(2-isocyanato-2-propyl)benzene, 2,2-bis(4-isocyanatophenyl)hexafluoropropane, dicyclohexylmethane-4,4'-diisocyanate, etc. <Dicarboxylic acid> Oxalic acid, malonic acid, succicic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, undecanediic acid, dodecanediic acid, terephthalic acid, isophthalic acid, 5-hydroxyisophthalic acid, 2-chloroterephthalic acid, 2-methylterephthalic acid, 5-methylisophthalic acid, 5-sodium sulfoisophthalic acid, hexahydroterephthalic acid, hexahydroisophthalic acid, cyclohexanedicarboxylic acid, biphenyldicarboxylic acid, naphthalenedicarboxylic acid, benzophenonedicarboxylic acid, francicarboxylic acid, 4,4'-dicarboxydiphenyl ether, 4,4'-dicarboxydiphenyl sulfide, etc. <Acid chlorides> Acetyl chloride, acrylate chloride, methacrylate chloride, malonyl chloride, succinate dichloride, diglycolyl chloride, glutarate dichloride, suberate dichloride, sebacate dichloride, adipic acid dichloride, dodecanediol dichloride, azera oil chloride, 2,5-franzicarbonyl dichloride, phthaloyl chloride, isophthaloyl chloride, terephthaloyl chloride, trimesinate chloride, bis(4-chlorocarbonylphenyl) ether, 4,4'-diphenyldicarbonyl chloride, 4,4'-azodibenzoyl dichloride, etc. <Lactam> ε-caprolactam, ω-undecanlactam, ω-laurolactam, etc.

[0068] [Polyimide resin] Examples of polyimide resins include, but are not limited to, the reaction products of the diamine and the tetracarboxylic dianhydride exemplified below. Furthermore, these may be used individually or in combination. Specific examples include compounds having the polyimide structure described in WO2023 / 013224A1. <Tetracarboxylic acid dianhydride> 4,4'-(hexafluoroisopropylidene)diphthalic anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methylcyclohexene-1,2-dicarboxylic acid anhydride, pyromellitic dianhydride, 1,2,3,4-benzenetetracarboxylic acid dianhydride, 3,3',4,4'-benzophenonetetracarboxylic acid dianhydride, 2,2',3,3'-benzophenonetetracarboxylic acid dianhydride, 3,3',4,4'-biphenyltetracarboxylic acid dianhydride, 3,3',4,4'-diphenylsulfonetetracarboxylic acid dianhydride, 2,2',3, 3'-Biphenyltetracarboxylic acid dianhydride, methylene-4,4'-diphthalic acid dianhydride, 1,1-ethylidene-4,4'-diphthalic acid dianhydride, 2,2'-propyridene-4,4'-diphthalic acid dianhydride, 1,2-ethylene-4,4'-diphthalic acid dianhydride, 1,3-trimethylene-4,4'-diphthalic acid dianhydride, 1,4-tetramethylene-4,4'-diphthalic acid dianhydride, 1,5-pentamethylene-4,4'-diphthalic acid dianhydride, 4,4'-oxydiphthalic acid dianhydride, thio-4,4'-diphthalic acid dianhydride, sulfonyl-4,4'-diphthalic acid Dianhydride, 1,3-bis(3,4-dicarboxyphenyl)benzene dianhydride, 1,3-bis(3,4-dicarboxyphenoxy)benzene dianhydride, 1,4-bis(3,4-dicarboxyphenoxy)benzene dianhydride, 1,3-bis[2-(3,4-dicarboxyphenyl)-2-propyl]benzene dianhydride, 1,4-bis[2-(3,4-dicarboxyphenyl)-2-propyl]benzene dianhydride, bis[3-(3,4-dicarboxyphenoxy)phenyl]methane dianhydride, bis[4-(3,4-dicarboxyphenoxy)phenyl]meth Dianhydride, 2,2-bis[3-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride, 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride, bis(3,4-dicarboxyphenoxy)dimethylsilane dianhydride, 1,3-bis(3,4-dicarboxyphenyl)-1,1,3,3-tetramethyldisiloxane dianhydride, 2,3,6,7-naphthalenetetracarboxylic acid dianhydride, 1,4,5,8-naphthalenetetracarboxylic acid dianhydride, 1,2,5,6-naphthalenetetracarboxylic acid dianhydride, 3,4,9,10-Perylenetetracarboxylic dianhydride, 2,3,6,7-Anthracenetetracarboxylic dianhydride, 1,2,7,8-Phenanthrenetetracarboxylic dianhydride, Ethylenetetracarboxylic dianhydride, 1,2,3,4-Butanetetracarboxylic dianhydride, 1,2,3,4-Cyclobutanetetracarboxylic dianhydride, Cyclopentanetetracarboxylic dianhydride, Cyclohexane-1,2,3,4-Tetocarboxylic dianhydride, Cyclohexane-1,2,4,5-Tetocarboxylic dianhydride Dianhydride of 3,3',4,4'-bicyclohexyltetracarboxylic acid dianhydride, carbonyl-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, methylene-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, 1,2-ethylene-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, 1,1-ethylidene-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, 2,2-propyridene- 4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, oxy-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, thio-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, sulfonyl-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, bicyclo[2,2,2]octo-7-ene-2,3,5,6-tetracarboxylic acid dianhydride, rel-[1S,5R,6R]-3-oxabicyclo[3,2 ,1] Octane-2,4-dione-6-spiro-3'-(tetrahydrofuran-2',5'-dione), 4-(2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid anhydride, ethylene glycol-bis-(3,4-dicarboxylic acid anhydride phenyl) ether, 4,4'-biphenylbis(trimellitic acid monoester anhydride), 9,9'-bis(3,4-dicarboxyphenyl)fluorene dianhydride, etc.

[0069] [Allyl compounds] Examples of the allyl compounds mentioned above include monoallyl isocyanurate, diallyl isocyanurate, and triallyl isocyanurate. Specific examples include "TAIC" (manufactured by Mitsubishi Chemical Corporation), "MA-DGIC," and "DA-MGIC" (both manufactured by Shikoku Chemicals Corporation).

[0070] [Polybutadiene and its modified forms] Polybutadiene and its modified products are compounds that contain polybutadiene or a structure derived from polybutadiene within their molecule. The structure derived from polybutadiene may have some or all of its unsaturated bonds converted to single bonds by hydrogenation. Examples of polybutadiene and its modified products include, but are not limited to, polybutadiene, hydroxyl-terminated polybutadiene, terminally (meth)acrylated polybutadiene, carboxylic acid-terminated polybutadiene, amine-terminated polybutadiene, and styrene-butadiene rubber. These may be used individually or in combination. Of these, polybutadiene or styrene-butadiene rubber is preferred from the viewpoint of dielectric properties. Examples of styrene-butadiene rubber (SBR) include RICON-100, RICON-181, RICON-184 (all manufactured by Clay Valley Corporation), and 1,2-SBS (manufactured by Nippon Soda Co., Ltd.), while examples of polybutadiene include B-1000, B-2000, and B-3000 (all manufactured by Nippon Soda Co., Ltd.). The weight-average molecular weight of polybutadiene and styrene-butadiene rubber is preferably 500 to 10000, more preferably 750 to 7500, and even more preferably 1000 to 5000. Below the lower limit of the above range, the volatilization rate is high, making it difficult to adjust the solid content during prepreg preparation, and above the upper limit of the above range, compatibility with other curable resins deteriorates. Generally, in the case of compounds containing heteroatoms such as oxygen and nitrogen, such as bismaleimide and polymaleimide, it is difficult to ensure compatibility with low-polarity compounds such as compounds composed mainly of hydrocarbons or compounds composed only of hydrocarbons, due to their polarity. On the other hand, the compound of this embodiment does not have a framework design that actively incorporates heteroatoms such as oxygen and nitrogen, and therefore exhibits excellent compatibility with materials that have low polarity and low dielectric properties, as well as compounds composed only of hydrocarbons.

[0071] [Polystyrene and its modified forms] Polystyrene and its modified products are compounds that have polystyrene or a structure derived from polystyrene within their molecule. Examples of polystyrene and its modified products include polystyrene, styrene-2-isopropenyl-2-oxazoline copolymer (Epocross RPS-1005, RP-61, both manufactured by Nippon Shokubai Co., Ltd.), SEP (styrene-ethylene-propylene copolymer: Septon® 1020, manufactured by Kuraray Co., Ltd.), SEPS (styrene-ethylene-propylene-styrene copolymer: Septon 2002, Septon 2004F, Septon 2005, Septon 2006, Septon 2063, Septon 2104, all manufactured by Kuraray Co., Ltd.), SEEPS (styrene-ethylene / ethylene-propylene-styrene block copolymer: Septon 4003, Septon 4044, Septon 4055, Septon 4077, Septon 4099, all manufactured by Kuraray Co., Ltd.), and SEBS (styrene-ethylene-butylene-styrene). Examples of block copolymers include, but are not limited to, Septon 8004, Septon 8006, Septon 8007L (all manufactured by Kuraray Co., Ltd.), SEEPS-OH (a compound having hydroxyl groups at the ends of styrene-ethylene / ethylene-propylene-styrene block copolymers: Septon HG252, manufactured by Kuraray Co., Ltd.), SIS (styrene-isoprene-styrene block copolymers: Septon 5125, Septon 5127, both manufactured by Kuraray Co., Ltd.), Hydrogenated SIS (hydrogenated styrene-isoprene-styrene block copolymers: Hybler® 7125F, Hybler 7311F, both manufactured by Kuraray Co., Ltd.), SIBS (styrene-isobutylene-styrene block copolymers: SIBSTAR® 073T, SIBSTAR 102T, SIBSTAR 103T (all manufactured by Kaneka Corporation), Septon V9827 (manufactured by Kuraray Co., Ltd.)), etc. Furthermore, these can be used individually or in combination of multiple types. Polystyrene and its modified products are preferable to be those without unsaturated bonds, as they have higher heat resistance and are less susceptible to oxidative degradation. In addition, there are no particular restrictions on the weight-average molecular weight of polystyrene and its modified products as long as it is 10,000 or more, but if it is too high, the compatibility with polyphenylene ether compounds, as well as low molecular weight components with a weight-average molecular weight of about 50 to 1,000 and oligomer components with a weight-average molecular weight of about 1,000 to 5,000 deteriorates, making it difficult to ensure mixing and solvent stability. Therefore, it is preferable that it be around 10,000 to 300,000.

[0072] [Polyethylene and its modified forms] Polyethylene and its modified products refer to polyethylene or compounds having a polyethylene-derived structure within their molecules. Examples of polyethylene and its modified products include, but are not limited to, ethylene-propylene copolymers, ethylene-styrene copolymers, ethylene-propylene-ethylidene norbornene copolymers (Mitsui Chemicals EBT: K-8370EM, K-9330M, etc.), ethylene-propylene-vinyl norbornene copolymers (Mitsui Chemicals VNB-EPT: PX-006M, PX-008M, PX-009M, etc.), ethylene-vinyl alcohol copolymers, and ethylene-vinyl acetate copolymers. From the viewpoint of improving heat resistance, it is preferable to use ethylene-propylene-ethylidene norbornene copolymers or ethylene-propylene-vinyl norbornene copolymers that contain a crosslinkable structure. Furthermore, these may be used individually or in combination of multiple types. While there are no particular restrictions on the weight-average molecular weight of polyethylene and its modified products as long as it is 10,000 or more, if it is too high, the compatibility with polyphenylene ether compounds, as well as low molecular weight components with a weight-average molecular weight of about 50 to 1,000 and oligomer components with a weight-average molecular weight of about 1,000 to 5,000 deteriorates, making it difficult to ensure mixing and solvent stability. Therefore, it is preferable that the molecular weight be around 10,000 to 300,000.

[0073] [Benzoxazine compounds] As the benzoxazine compound, any compound obtained by reacting a compound having a phenolic hydroxyl group, a compound having an amino group, or a compound having an aldehyde group may be used. The compound having a phenolic hydroxyl group is not particularly limited, but for example, the aforementioned phenolic resins, phenols (which may have substituents such as alkenyl groups or alkyl groups), and bisphenols can be used. The compound having an amino group is not particularly limited, but for example, the aforementioned amine resins, diamines, and anilines (which may have substituents such as alkenyl groups or alkyl groups) can be used. As the aldehyde compound, for example, the aforementioned aldehydes can be used, but formaldehyde is preferred. Commercially available benzoxazine compounds may be used, including benzoxazine Pd, Fa, ALP-d (all manufactured by Shikoku Chemicals Co., Ltd.), JBZ-BA100N, JBZ-FA100N, JBZ-DP100N, JBZ-OP100N, JBZ-OP100D, JBZ-OP100I (all manufactured by JFE Chemical Corporation), and BTBz (manufactured by Nippon Materials Technology Co., Ltd.).

[0074] [Curing accelerator] A curing accelerator may be added to the curable resin composition of this embodiment as needed. Preferably, the curing accelerator is an anionic curing accelerator that promotes the curing reaction by generating anions upon irradiation with ultraviolet light or visible light or by heating, or a cationic curing accelerator that promotes the curing reaction by generating cations upon irradiation with ultraviolet light or visible light or by heating.Examples of usable curing accelerators include imidazoles such as 2-methylimidazole, 2-ethylimidazole, 2-phenylimidazole, 1,2-dimethylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, and 2-ethyl-4-methylimidazole (2E4MZ), as well as triethylamine, tributylamine, N,N-dimethyl-4-aminopyridine (DMAP), and 2,4,6-tris(dimethylaminomethyl). Tertiary amines such as phenol, 2-(dimethylaminomethyl)phenol, triethylenediamine, triethanolamine, 1,8-diazabicyclo(5,4,0)undecene-7 (DBU), 1,5-diazabicyclo[4,3,0]-nonene-5 (DBN), organophosphines such as triphenylphosphine (TPP), diphenylphosphine, tributylphosphine, triparathylphosphine, diphenylcyclohexylphosphine, tricyclohexylphosphine, trimethylphosphine, triethylphosphine Examples include organic phosphites such as tyl phosphite, tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium ethyltriphenylborate, ethyltriphenylphosphonium bromide, benzyltriphenylphosphonium chloride, butylphosphonium tetraphenylborate, tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium tetra-p-tolylborate, triphenylphosphinetriphenylborane, tetraphenylphosphonium thiocyanate, tetraphenylphosphonium dicyanamide, butylphenylphosphonium dicyanamide, tetrabutylphosphonium decanoate, and other phosphonium salts, metal compounds such as octopz(2-ethylhexanoate) and tin octylate, tetraphenylborone salts such as 2-ethyl-4-methylimidazole tetraphenylborate and N-methylmorpholine tetraphenylborate, and carboxymethyl phosphate compounds such as benzoic acid, phthalic acid, isophthalic acid, terephthalic acid, naphthoic acid, and salicylic acid.

[0075] In the curable resin composition of this embodiment, from the viewpoint of curability, it is preferable to use a phosphorus-based curing accelerator or an imidazole-based curing accelerator among the above curing accelerators, and from the viewpoint of insulation reliability, a phosphorus-based curing accelerator is preferred. The above curing accelerators may be used alone or in combination of two or more types.

[0076] The curing accelerator is used as needed, in an amount of 0.01 to 15 parts by weight per 100 parts by weight of epoxy resin.

[0077] [Inorganic fillers] Furthermore, inorganic fillers may be added to the curable resin composition of this embodiment as needed. Examples of inorganic fillers include, but are not limited to, powders such as crystalline silica, fused silica, synthetic silica, hollow silica, alumina, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, aluminum hydroxide, magnesium hydroxide, zircon, calcium silicate, calcium carbonate, magnesium carbonate, magnesium oxide, silicon carbide, silicon nitride, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconium oxide, barium titanate, barium zirconate titanate, barium zirconate, calcium zirconate, zirconium phosphate, zirconium tungstate phosphate, clay, zirconia, fossilite, steatite, spinel, titania, talc, mica powder, zinc oxide, hydrotalcite, boehmite, carbon black, or beads made by shaping these into spheres. These may be used individually or in combination of two or more. The amount of these inorganic fillers used varies depending on the application, but for example, when used as a encapsulant for semiconductors, it is preferable to use them in a proportion of 20% by weight or more in the curable resin composition, more preferably 30% by weight or more, and even more preferably 70-95% by weight in order to improve the coefficient of linear expansion with the lead frame.

[0078] The curable resin composition of this embodiment may contain a release agent to improve mold release during molding. Any conventionally known release agent can be used, but examples include ester waxes such as carnauba wax and montane wax, fatty acids such as stearic acid and palmitic acid and their metal salts, and polyolefin waxes such as oxidized polyethylene and non-oxidized polyethylene. These may be used alone or in combination of two or more. The amount of these release agents added is preferably 0.5 to 3% by weight relative to the total organic components. Too little will result in poor mold release, while too much will result in poor adhesion to the lead frame and the like.

[0079] [Coupling agent] The curable resin composition of this embodiment may contain a coupling agent to enhance the adhesion between the inorganic filler and the resin component. Any conventionally known coupling agent can be used, but examples include epoxyalkoxysilanes such as vinylalkoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, various alkoxysilane compounds such as styrylalkoxysilane, methacryloxyalkoxysilane, acryloxyalkoxysilane, aminoalkoxysilanes such as N-β(aminoethyl)-γ-aminopropyltrimethoxysilane, mercaptoalkoxysilanes such as γ-mercaptopropyltrimethoxysilane and γ-mercaptopropylmethyldimethoxysilane, isocyanatealkoxysilane, alkoxytitanium compounds, and aluminum chelates. These may be used alone or in combination of two or more. The coupling agent can be added either by first treating the surface of the inorganic filler with the coupling agent and then mixing it with the resin, or by mixing the coupling agent with the resin and then mixing in the inorganic filler.

[0080] [Flame retardant] The curable resin composition of this embodiment may contain a flame retardant. Examples of flame retardants include halogen-based flame retardants, inorganic flame retardants (antimony compounds, metal hydroxides, nitrogen compounds, boron compounds, etc.), and phosphorus-based flame retardants, but phosphorus-based flame retardants are preferred from the viewpoint of achieving halogen-free flame retardancy.

[0081] The phosphorus-based flame retardants mentioned above may be reactive or additive types. Specific examples include phosphorus esters such as trimethyl phosphate, triethyl phosphate, tricresyl phosphate, trixyllenyl phosphate, cresyl diphenyl phosphate, cresyl-2,6-dixyllenyl phosphate, 1,3-phenylenebis(dixyllenyl phosphate), 1,4-phenylenebis(dixyllenyl phosphate), and 4,4'-biphenyl(dixyllenyl phosphate); phosphanes such as 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and 10(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide; phosphorus-containing epoxy compounds obtained by reacting epoxy resin with the active hydrogen of the aforementioned phosphanes; and red phosphorus, but are not limited to these. Furthermore, these may be used individually or in combination of multiple types. Among the above example substances, phosphate esters, phosphans, or phosphorus-containing epoxy compounds are preferred, and 1,3-phenylenebis(dixyllenyl phosphate), 1,4-phenylenebis(dixyllenyl phosphate), 4,4'-biphenyl(dixyllenyl phosphate), or phosphorus-containing epoxy compounds are particularly preferred.

[0082] The flame retardant content is preferably in the range of 0.1 to 0.6 parts by mass per 100 parts by mass of the curable resin composition. If the content is less than 0.1 parts by mass, the flame retardancy may be insufficient, and if it is more than 0.6 parts by mass, it may adversely affect the hygroscopicity and dielectric properties of the cured product.

[0083] [Polymerization initiator] The curable resin composition of this embodiment can also have its curability improved by adding a polymerization initiator. A polymerization initiator is a compound capable of polymerizing olefin functional groups such as ethylenically unsaturated bonds, and examples include olefin metathesis polymerization initiators, anionic polymerization initiators, cationic polymerization initiators, and radical polymerization initiators. Among these, it is preferable to use a radical polymerization initiator that has both curability and appropriate stability. A radical polymerization initiator is a compound that generates radicals upon irradiation with ultraviolet or visible light or heating, thereby initiating a chain polymerization reaction. Examples of radical polymerization initiators that can be used include organic peroxides, azo compounds, and benzopinacols, and it is preferable to use organic peroxides because they have less influence on curing temperature control, outgassing suppression, and the electrical properties of decomposition products.

[0084] Examples of the above organic peroxides include ketone peroxides such as methyl ethyl ketone peroxide and acetylacetone peroxide, diacyl peroxides such as benzoyl peroxide, dialkyl peroxides such as dicumyl peroxide (DCP) and 1,3-bis-(t-butylperoxyisopropyl)benzene, peroxyketals such as t-butyl peroxybenzoate and 1,1-di-t-butylperoxycyclohexane, α-cumyl peroxyneodecanoate, t-butyl peroxyneodecanoate, t-butyl peroxypivalate, 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate, and t-amyl peroxy-2-ethylhexanoate. Examples include alkyl peresters such as noates, t-butyl peroxy-2-ethylhexanoate, t-amyl peroxy-3,5,5-trimethylhexanoate, t-butyl peroxy-3,5,5-trimethylhexanoate, and t-amyl peroxybenzoate; peroxycarbonates such as di-2-ethylhexyl peroxydicarbonate, bis(4-t-butylcyclohexyl) peroxydicarbonate, t-butyl peroxyisopropyl carbonate, and 1,6-bis(t-butyl peroxycarbonyloxy)hexane; t-butyl hydroperoxide, cumene hydroperoxide, t-butyl peroxyoctoate, and lauroyl peroxide. Specific examples include Irgacure OXE-04 and Irgacure 290 (both manufactured by BASF), but are not limited to these. Furthermore, these can be used individually or in combination. Among the above organic peroxides, ketone peroxides, diacyl peroxides, hydroperoxides, dialkyl peroxides, peroxyketals, alkyl peresters, and peroxycarbonates are preferred, with dialkyl peroxides being more preferred.

[0085] Examples of the above-mentioned azo compounds include, but are not limited to, azobisisobutyronitrile, 4,4'-azobis(4-cyanovaleric acid), and 2,2'-azobis(2,4-dimethylvaleronitrile). Furthermore, these compounds may be used individually or in combination.

[0086] The amount of polymerization initiator added is preferably 0.01 to 5 parts by mass, and particularly preferably 0.01 to 3 parts by mass, per 100 parts by mass of the curable resin composition. If the amount of polymerization initiator used is less than 0.01 parts by mass, the molecular weight may not elongate sufficiently during the polymerization reaction, and if it is more than 5 parts by mass, dielectric properties such as dielectric constant and dielectric loss tangent may be impaired.

[0087] [Polymerization inhibitor] The curable resin composition of this embodiment may contain a polymerization inhibitor. Including a polymerization inhibitor improves storage stability and allows control of the reaction initiation temperature. Controlling the reaction initiation temperature makes it easier to ensure fluidity, prevents impregnation of glass cloth and the like, and facilitates B-stage processes such as prepreg formation. If the polymerization reaction proceeds too far during prepreg formation, problems such as difficulty in lamination during the lamination process are likely to occur.

[0088] The polymerization inhibitor may be added during the synthesis of the compound of this embodiment or after the synthesis. The amount of polymerization inhibitor used is 0.008 to 1 part by weight, preferably 0.01 to 0.5 parts by weight, per 100 parts by weight of the compound of this embodiment.

[0089] Examples of polymerization inhibitors include phenol-based, sulfur-based, phosphorus-based, hindered amine-based, nitroso-based, and nitroxyl radical-based agents. Furthermore, polymerization inhibitors may be used individually or in combination of multiple types. Of these, phenol-based, hindered amine-based, nitroso-based, and nitroxyl radical-based agents are preferred in this embodiment.

[0090] Examples of the above phenolic polymerization inhibitors include 2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-butyl-p-ethylphenol, stearyl-β-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, isooctyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, 2,4-bis-(n-octylthio)-6-(4-hydroxy-3,5-di-t-butylanilino)-1,3,5-triazine, and 2,4-bis[(octylthio)methyl]-o-c Monophenols such as resols, 2,2'-methylenebis(4-methyl-6-t-butylphenol), 2,2'-methylenebis(4-ethyl-6-t-butylphenol), 4,4'-thiobis(3-methyl-6-t-butylphenol), 4,4'-butylidenebis(3-methyl-6-t-butylphenol), triethylene glycol-bis[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate], 1,6-hexanediol-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate] [T], N,N'-Hexamethylenebis(3,5-di-t-butyl-4-hydroxy-hydrocinnamamide), 2,2-thio-diethylenebis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 3,5-di-t-butyl-4-hydroxybenzylphosphonate-diethyl ester, 3,9-bis[1,1-dimethyl-2-{β-(3-t-butyl-4-hydroxy-5-methylphenyl)propionyloxy}ethyl]2,4,8,10-tetraoxaspiro[5,5]undecane, bis(3,5-di-t- Bisphenols such as calcium ethyl hydroxybenzylsulfonate, 1,1,3-tris(2-methyl-4-hydroxy-5-t-butylphenyl)butane, 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, tetrakis-[methylene-3-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate]methane, bis[3,3'-bis-(4'-hydroxy-3'-t-butylphenyl)butyric acid]glycol ester, tris-(3,Examples include, but are not limited to, high molecular weight phenols such as 5-di-t-butyl-4-hydroxybenzyl)-isocyanurate, 1,3,5-tris(3',5'-di-t-butyl-4'-hydroxybenzyl)-S-triazine-2,4,6-(1H,3H,5H)trione, and tocopherol.

[0091] Examples of sulfur-based polymerization inhibitors include, but are not limited to, dilauryl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, and distearyl-3,3'-thiodipropionate.

[0092] Examples of the phosphorus polymerization inhibitors mentioned above include triphenyl phosphite, diphenylisodecyl phosphite, phenyldiisodecyl phosphite, tris(nonylphenyl) phosphite, diisodecylpentaerythritol phosphite, tris(2,4-di-t-butylphenyl) phosphite, cyclic neopentanetetraylbis(octadecyl) phosphite, cyclic neopentanetetraylbis(2,4-di-t-butylphenyl) phosphite, cyclic neopentanetetraylbis(2,4-di-t-butyl-4-methylphenyl) phosphite, and bis[2- Examples include, but are not limited to, phosphites such as t-butyl-6-methyl-4-{2-(octadecyloxycarbonyl)ethyl}phenyl]hydrogen phosphite, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10-(3,5-di-t-butyl-4-hydroxybenzyl)-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, and 10-decyloxy-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide.

[0093] Examples of the above hindered amine polymerization inhibitors include Adekastab (registered trademark) LA-40MP, Adekastab LA-40Si, Adekastab LA-402AF, Adekastab LA-87, Adekastab LA-82, Adekastab LA-81, Adekastab LA-77Y, Adekastab LA-77G, Adekastab LA-72, Adekastab LA-68, Adekastab LA-63P, Adekastab LA-57, Adekastab LA-52 (all from ADE Inc.) Examples include, but are not limited to, products such as KA, Chimassorb® 2020FDL, Chimassorb 944FDL, Chimassorb 944LD, Tinuvin® 622SF, Tinuvin PA144, Tinuvin 765, Tinuvin 770DF, Tinuvin XT55FB, Tinuvin 111FDL, Tinuvin 783FDL, and Tinuvin 791FB (all manufactured by BASF).

[0094] Examples of the nitroso polymerization inhibitors mentioned above include, but are not limited to, p-nitrosophenol, N-nitrosodiphenylamine, and ammonium salts of N-nitrosophenylhydroxyamine (cuperone). Of these, ammonium salts of N-nitrosophenylhydroxyamine (cuperone) are preferred.

[0095] Examples of the above-mentioned nitroxyl radical polymerization inhibitors include, but are not limited to, di-tert-butylnitroxide, 2,2,6,6-tetramethylpiperidine-1-oxyl, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl, 4-oxo-2,2,6,6-tetramethylpiperidine-1-oxyl, 4-amino-2,2,6,6-tetramethylpiperidine-1-oxyl, 4-methoxy-2,2,6,6-tetramethylpiperidine-1-oxyl, 4-acetoxy-2,2,6,6-tetramethylpiperidine-1-oxyl, and 4-benzoyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl.

[0096] [Light stabilizer] The curable resin composition of this embodiment may also contain a light stabilizer. Suitable light stabilizers include hindered amine light stabilizers (HALS). Examples of HALS include the reaction product of dibutylamine·1,3,5-triazine·N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl-1,6-hexamethylenediamine and N-(2,2,6,6-tetramethyl-4-piperidyl)butylamine, the reaction product of dimethyl-1-(2-hydroxyethyl)-4-hydroxy-2,2,6,6-tetramethylpiperidine succinate, poly[{6-(1,1,3,3-tetramethylbutyl)amino-1,3,5-triazine-2,4-diyl}{(2,2,6,6-tetramethyl-4-piperidyl)imino}hexamethylene{(2,2,6,6-tetramethyl-4-piperidyl)imino}], bis(1,2 Examples include, but are not limited to, 2,6,6-pentamethyl-4-piperidyl)[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]butylmalonate, bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, bis(1-octyroxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, and 2-(3,5-di-t-butyl-4-hydroxybenzyl)-2-n-butylmalonate bis(1,2,2,6,6-pentamethyl-4-piperidyl). Furthermore, these may be used individually or in combination.

[0097] The amount of light stabilizer is preferably in the range of 0.001 to 0.1 parts by mass per 100 parts by mass of the curable resin composition. If the amount is less than 0.001 parts by mass, it may be insufficient to exhibit the light stabilization effect, and if it is more than 0.1 parts by mass, it may adversely affect the hygroscopicity and dielectric properties of the cured product.

[0098] [Binder resin] The curable resin composition of this embodiment may also use a binder resin. Examples of binder resins include, but are not limited to, but include butyral resins, acetal resins, acrylic resins, epoxy-nylon resins, NBR-phenolic resins, epoxy-NBR resins, and silicone resins. Furthermore, these may be used individually or in combination of multiple types.

[0099] The amount of binder resin added is preferably within a range that does not impair the flame retardancy and heat resistance of the cured product, and is preferably 0.05 to 50 parts by mass per 100 parts by mass of the curable resin composition, and more preferably 0.05 to 20 parts by mass as needed.

[0100] Furthermore, known additives may be added to the curable resin composition of this embodiment as needed. Specific examples of additives that can be used include polybutadiene and its modified forms, modified acrylonitrile copolymers, polystyrene, polyethylene, fluororesins, silicone gels, silicone oils, and colorants such as carbon black, phthalocyanine blue, and phthalocyanine green.

[0101] The amount of additive added is preferably 30 parts by mass or less, more preferably 20 parts by mass or less, and particularly preferably 10 parts by mass or less, per 100 parts by mass of the curable resin composition.

[0102] The curable resin composition of this embodiment is obtained by preparing the above components in predetermined proportions, pre-curing at 130-180°C for 30-500 seconds, and then post-curing at 150-200°C for 2-15 hours to allow the curing reaction to proceed sufficiently and obtain the cured product of this embodiment. Alternatively, the components of the curable resin composition can be uniformly dispersed or dissolved in a solvent, and then cured after removing the solvent.

[0103] The method for preparing the curable resin composition of this embodiment is not particularly limited, but may be done by simply mixing each component uniformly or by prepolymerization. For example, prepolymerization can be performed by heating a mixture containing the compounds of this embodiment in the presence or absence of a curing accelerator and polymerization initiator, in the presence or absence of a solvent. Similarly, prepolymerization may be performed by adding compounds such as amine compounds, compounds having ethylenically unsaturated bonds, maleimide compounds, cyanate ester compounds, polybutadiene and its modified products, polystyrene and its modified products, inorganic fillers, and other additives. Mixing or prepolymerization of each component can be performed using, for example, an extruder, kneader, or roll in the absence of a solvent, and a reaction vessel with a stirring device can be used in the presence of a solvent.

[0104] For uniform mixing, the resin composition is kneaded using equipment such as a kneader, roll, or planetary mixer at a temperature in the range of 50 to 100°C. After pulverization, the resulting resin composition can be molded into cylindrical tablets using a molding machine such as a tablet machine, or into granular powder or powdered molded bodies. Alternatively, these compositions can be melted on a surface support and molded into sheets with a thickness of 0.05 mm to 10 mm to produce curable resin composition molded bodies. The resulting molded bodies are non-sticky at 0 to 20°C and maintain almost no decrease in fluidity or curability even after storage at -25 to 0°C for more than a week. The resulting molded body can be molded into a hardened product using a transfer molding machine or a compression molding machine.

[0105] The curable resin composition of this embodiment can also be converted into a varnish-like composition (hereinafter simply referred to as varnish) by adding an organic solvent. The curable resin composition of this embodiment can be dissolved in a solvent such as toluene, xylene, acetone, methyl ethyl ketone, methyl isobutyl ketone, dimethylformamide, dimethylacetamide, or N-methylpyrrolidone as needed to form a varnish, which can then be impregnated into a substrate such as glass fiber, carbon fiber, polyester fiber, polyamide fiber, alumina fiber, or paper, and heated and dried to obtain a prepreg. The resulting prepreg can then be hot-press-molded to obtain a cured product of the curable resin composition of this embodiment. In this case, the solvent used should account for 10 to 70% by weight, preferably 15 to 70% by weight, of the mixture of the curable resin composition of this embodiment and the solvent. If the composition is liquid, a cured product of the curable resin containing carbon fibers can also be obtained directly, for example, by the RTM method.

[0106] Furthermore, the curable resin composition of this embodiment can also be used as a modifier for film-type compositions. Specifically, it can be used to improve flexibility and other properties in the B-stage. Such a film-type resin composition can be obtained as a sheet-like adhesive by applying the curable resin composition of this embodiment as a varnish onto a release film, removing the solvent under heating, and then performing the B-stage process. This sheet-like adhesive can be used as an interlayer insulating layer in multilayer substrates and the like.

[0107] The curable resin composition of this embodiment can also be heated and melted to reduce viscosity and impregnate reinforcing fibers such as glass fibers, carbon fibers, polyester fibers, polyamide fibers, and alumina fibers to obtain a prepreg. Specific examples include, but are not limited to, glass fibers such as E glass cloth, D glass cloth, S glass cloth, Q glass cloth, spherical glass cloth, NE glass cloth, and T glass cloth, as well as inorganic fibers other than glass, and organic fibers such as poly(p-phenylene terephthalamide) (Kevlar®, manufactured by DuPont), fully aromatic polyamide, polyester, poly(p-phenylene benzoxazole), polyimide, and carbon fiber. The shape of the substrate is not particularly limited, but examples include woven fabrics, nonwoven fabrics, rovings, and chopped strand mats. As for the weaving method of the woven fabric, plain weave, twill weave, etc., are known, and these can be appropriately selected and used depending on the intended application and performance. Furthermore, glass woven fabrics that have been opened or surface-treated with silane coupling agents are preferably used. The thickness of the base material is not particularly limited, but is preferably about 0.01 to 0.4 mm. Alternatively, a prepreg can be obtained by impregnating reinforcing fibers with the varnish and then heating and drying them.

[0108] Furthermore, laminates can also be manufactured using the above-mentioned prepregs. The laminate is not particularly limited as long as it comprises one or more prepregs, and may have any other layers. The method for manufacturing the laminate is not particularly limited and can be any generally known method as appropriate. For example, when forming a metal foil laminate, a multi-stage press, a multi-stage vacuum press, a continuous molding machine, an autoclave molding machine, etc., can be used, and a laminate can be obtained by laminating the above-mentioned prepregs together and heating and pressing them. At this time, the heating temperature is not particularly limited, but 65 to 300°C is preferred, and 120 to 270°C is more preferred. The pressurizing pressure is not particularly limited, but if the pressurizing pressure is too high it is difficult to adjust the solid content of the resin in the laminate and the quality is not stable, and if the pressurizing pressure is too low it becomes difficult to form air bubbles and the adhesion between layers is poor, so 2.0 to 5.0 MPa is preferred, and 2.5 to 4.0 MPa is more preferred. The laminate of this embodiment can be suitably used as a metal foil laminate described later by comprising a layer made of metal foil. By cutting the above prepreg into the desired shape, laminating it with copper foil or other materials as needed, and then applying pressure to the laminate using methods such as press molding, autoclave molding, or sheet winding molding while heating and curing a curable resin composition, electrical and electronic laminates (printed wiring boards) and carbon fiber reinforced materials can be obtained.

[0109] The curable resin composition of this embodiment can also be made into a resin sheet. One method for obtaining a resin sheet from the curable resin composition of this embodiment is to apply the curable resin composition onto a support film (support), dry it, and then form a resin composition layer on the support film. When the curable resin composition of this embodiment is used to make a resin sheet, it is important that the film softens at the lamination temperature conditions (70°C to 140°C) in the vacuum lamination method and exhibits fluidity (resin flow) that allows for simultaneous lamination of the circuit board and resin filling of via holes or through holes present in the circuit board. It is preferable to blend each component in such a way as to exhibit such characteristics. Furthermore, in order to ensure that the resulting resin sheet and circuit board (copper-clad laminate, etc.) exhibit consistent performance in any desired area, and to prevent phenomena such as locally different characteristic values ​​caused by phase separation, uniformity of appearance is required.

[0110] Here, the diameter of the through-holes in the circuit board is 0.1 to 0.5 mm, and the depth is 0.1 to 1.2 mm. It is preferable to be able to fill the holes with resin within this range. When laminating both sides of the circuit board, it is desirable that the through-holes be filled to about half their extent.

[0111] A specific method for manufacturing the aforementioned resin sheet is to prepare a varnished resin composition by incorporating an organic solvent, apply the varnished resin composition to the surface of a support film (Y), and then dry the organic solvent by heating or blowing hot air to form a resin composition layer (X).

[0112] The organic solvents used here preferably include ketones such as acetone, methyl ethyl ketone, and cyclohexanone; acetic acid esters such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, and carbitol acetate; carbitols such as cellosolve and butyl carbitol; aromatic hydrocarbons such as toluene and xylene; dimethylformamide, dimethylacetamide, and N-methylpyrrolidone. It is also preferable to use the organic solvent in a proportion such that the non-volatile content is 30 to 60% by mass of the total.

[0113] Furthermore, the thickness of the formed resin composition layer (X) must be greater than or equal to the thickness of the conductive layer of the circuit board to which the resin composition layer (X) is laminated. Since the thickness of the conductive layer of the circuit board is in the range of 5 to 70 μm, it is preferable that the thickness of the resin composition layer (X) be 10 to 100 μm. In addition, the resin composition layer (X) in this embodiment may be protected by a protective film, which will be described later. By protecting it with a protective film, it is possible to prevent dirt and other debris from adhering to the surface of the resin composition layer (X) and to prevent scratches.

[0114] The support film and protective film can be made of polyolefins such as polyethylene, polypropylene, and polyvinyl chloride, polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate, polycarbonate, polyimide, and also release paper, copper foil, aluminum foil, and other metal foils. The support film and protective film may be treated with a mat treatment, corona treatment, or release treatment. The thickness of the support film is not particularly limited, but is 10 to 150 μm, preferably in the range of 25 to 50 μm. The thickness of the protective film is preferably 1 to 40 μm.

[0115] The support film (Y) is peeled off after the resin composition layer (X) is laminated to the circuit board, or after an insulating layer is formed by heat curing the resin composition layer (X). If the support film (Y) is peeled off after the resin composition layer (X) constituting the resin sheet has been heat cured, it is possible to prevent the adhesion of dust and other debris during the curing process. When the support film (Y) is peeled off after the resin composition layer (X) has been cured, the support film (Y) is subjected to a release treatment beforehand.

[0116] Furthermore, a multilayer printed circuit board can be manufactured from the resin sheet obtained as described above. For example, if the resin composition layer (X) is protected by a protective film, the protective film is peeled off from the resin composition layer (X), and then the resin composition layer (X) is laminated to one or both sides of the circuit board so that it is in direct contact with the circuit board, for example, by a vacuum lamination method. The lamination method may be batch type or continuous type using a roll. In addition, if necessary, the resin sheet and circuit board may be heated (preheated) before lamination. The lamination conditions are preferably a pressure temperature (lamination temperature) of 70 to 140°C and a pressure of 1 to 11 kgf / cm². 2 (9.8 × 10 4 ~107.9×10 4 N / m 2 It is preferable to use this method, and it is preferable to laminate under reduced pressure of 20 mmHg (26.7 hPa) or less.

[0117] Furthermore, semiconductor devices can be manufactured using the curable resin composition of this embodiment. Examples of semiconductor devices include DIP (Dual In-Line Package), QFP (Quad Flat Package), BGA (Ball Grid Array), CSP (Chip Size Package), SOP (Small Outline Package), TSOP (Thin Small Outline Package), and TQFP (Thin Quad Flat Package).

[0118] The cured product obtained in this embodiment can be used for various applications. Specifically, it can be used in general applications where thermosetting resins such as epoxy resins are used, such as adhesives, paints, coatings, molding materials (including sheets, films, FRP, etc.), insulating materials (including printed circuit boards, wire coatings, etc.), sealants, and as an additive to other resins.

[0119] Adhesives include those for civil engineering, construction, automotive, general office, and medical applications, as well as adhesives for electronic materials. Among these, adhesives for electronic materials include interlayer adhesives for multilayer substrates such as build-up substrates, die bonding agents, semiconductor adhesives such as underfills, underfills for BGA reinforcement, and adhesives for mounting such as anisotropic conductive films (ACF) and anisotropic conductive pastes (ACP).

[0120] Examples of encapsulants include potting, dipping, and transfer molding encapsulation for capacitors, transistors, diodes, light-emitting diodes, ICs, and LSIs; potting encapsulation for COB, COF, and TAB of ICs and LSIs; underfill for flip chips; and encapsulation during mounting of IC packages such as QFP, BGA, and CSP (including reinforcing underfill). [Examples]

[0121] Next, the present invention will be described in more detail with reference to examples. Hereinafter, unless otherwise specified, parts refer to parts by mass. However, the present invention is not limited to these examples.

[0122] The various analytical methods used in the examples are described below. • GPC (Gel Permeation Chromatography) Analysis Equipment: DGU-20A, LC-20AD, SIL-20A, RID-20A, SPD-M40, CTО-20A, CBM-20A Columns: SHODEX GPC KF-601 (2 pieces), KF-602, KF-602.5, KF-603 Flow rate: 1.5ml / min. Column temperature: 40℃ Solvent used: THF (tetrahydrofuran) Detector: RI (Differential Refraction Detector) • ICI viscosity (150°C): Measured according to the method compliant with JIS K-7117-2. • Softening point: Measured using a METLER TOLEDO FP90 softening point meter. • Epoxy equivalent: Measured according to the method in accordance with JIS K-7236.

[0123] [Synthesis Example 1] In a flask equipped with a thermometer, condenser, and stirrer, 311.6 parts of 3-methyl-6-t-butylphenol, 0.4 parts of 4-methyl-2-t-butylphenol, 122 parts of salicylaldehyde, 217 parts of methanol, and 5 parts of methanesulfonic acid were added while purging with nitrogen. The mixture was heated to 60°C and reacted for 13 hours. After cooling to room temperature, 4.4 parts of 48% sodium hydroxide aqueous solution were added to neutralize the mixture, and the solvent was recovered under reduced pressure at 60°C to obtain a phenolic resin (P1) represented by the following formula (c-2) as a yellow powder. The GPC chart is shown in Figure 1 (the number-average molecular weight Mn was 581 and the weight-average molecular weight Mw was 601). The hydroxyl group equivalent calculated from the area % of the GPC was 144 g / eq. (The yield was 417 parts, of which 7 g of salt was contained). The total peak area derived from the raw materials 3-methyl-6-t-butylphenol and 4-methyl-2-t-butylphenol was 0.5 area%, the peak area derived from the component where n=1 is represented by the following formula (c-2) was 91.6 area%, and the peak area derived from compounds with a higher molecular weight than n=1 of the compound represented by the following formula (c-2) was 7.9 area.

[0124] [ka]

[0125] [Synthesis Example 2] In a flask equipped with a thermometer, condenser, and stirrer, 407 parts of the phenolic resin (P1) obtained in Synthesis Example 1 were added under nitrogen purging. 1305 parts of epichlorohydrin, 386 parts of dimethyl sulfoxide, and 23 parts of water were added, and the internal temperature was raised to 45°C. 114 parts of sodium hydroxide were added in installments over 3 hours, and the mixture was reacted at 45°C for 1.5 hours and at 70°C for 0.5 hours. Under reduced pressure, the solvent and excess epichlorohydrin were removed by distillation, and 1280 parts of methyl isobutyl ketone were added. After washing the organic layer with 670 parts of water, 25.3 parts of 30 wt% sodium hydroxide aqueous solution, 26.9 parts of methanol, and 25 parts of water were added, and the mixture was reacted at 75°C for 1 hour. The organic layer was washed with water until the wastewater was neutral, and the resulting solution was removed by distillation under reduced pressure to obtain 525 parts of epoxy resin (E1) represented by the following formula (d-2) as a yellow solid. The epoxy equivalent was 216 g / eq., the ICI viscosity at 150°C was 0.04 Pa·s, and the softening point was 72.4°C. The GPC chart of the obtained epoxy resin (E1) is shown in Figure 2 (number-average molecular weight Mn was 593, and weight-average molecular weight Mw was 644). The total peak area derived from the reaction product of 3-methyl-6-t-butylphenol and epihalohydrin, and the reaction product of 4-methyl-2-t-butylphenol and epihalohydrin was 0.3 area%, the peak area derived from the component n=1 of the compound represented by the following formula (d-2) was 86.0 area%, and the peak area derived from a compound with a higher molecular weight than the compound represented by the following formula (d-2) was 13.7 area.

[0126] [ka]

[0127] [Example 1 and Comparative Example 1] The epoxy resin (E1) obtained in Synthesis Example 2, along with the epoxy resin represented by the following formula (e) (FAE-2500, manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 216 g / eq., softening point 86°C, ICI viscosity at 150°C 0.29 Pa·s), phenol novolac resin (manufactured by Meiwa Kasei Co., Ltd., PN(H-1), softening point 85°C, hydroxyl group equivalent 104 g / eq), and triphenylphosphine (hereinafter also referred to as TPP) as a curing accelerator were blended in the proportions (parts by weight) shown in Table 1, uniformly mixed and kneaded using a mixing roll, and after demolding, cured at 160°C for 2 hours and 180°C for 6 hours to obtain test specimens for evaluation.

[0128] [ka]

[0129] [Geltime] The time it took for the mixture to gel was measured on a hot plate heated to 175°C. [Heat resistance / Glass transition temperature (Tg)] The temperature at which tanδ is at its maximum value was measured using a dynamic viscoelasticity tester. Dynamic viscoelasticity measuring instrument: TA-instruments DMA-2980 Heating rate: 2°C / min [5% weight loss temperature] Using a TG / DTA6200 (manufactured by Hitachi High-Tech Science Corporation), measurements were taken from 30°C to 300°C with a nitrogen gas flow rate of 200 mL / min and a heating rate of 10°C / min. [Flexural modulus] Measurements were taken in accordance with JIS K-6911 at 30°C. [Water absorption rate] After measuring the initial mass of a disc-shaped test specimen measuring 5 cm in diameter and 4 mm in thickness, the specimen was immersed in 100°C water and held for 24 hours. The mass was then measured, and the water absorption rate was calculated using the following formula. Water absorption rate (%) = (Mass after 24 hours - Initial mass) / Mass after 24 hours

[0130] [Table 1]

[0131] Example 1, a curable resin composition of the present invention, was found to have excellent fluidity in terms of a long gel time and the ability to maintain low viscosity for a long period after melting. Furthermore, its cured product was found to have good heat resistance, as it has a glass transition temperature of 200°C or higher, and was also found to have excellent elastic modulus and low water absorption.

[0132] <Curing test> [Reference example 1] 25 parts of the compound (E1) obtained in Synthesis Example 2, 20 parts of NC-3000 (manufactured by Nippon Kayaku Co., Ltd., biphenyl aralkyl type epoxy resin), 0.5 parts of MDEA: 4,4'-methylenebis(2-ethyl-6-methylaniline) (manufactured by Tokyo Chemical Industry Co., Ltd., amine compound), 1 part of DICY: dicyandiamide (manufactured by Tokyo Chemical Industry Co., Ltd., amide compound), 0.5 parts of KAYAHARD MCD (manufactured by Nippon Kayaku Co., Ltd., acid anhydride compound), KAYAHARD 0.5 parts of GPH-65 (manufactured by Nippon Kayaku Co., Ltd., biphenylaralkyl type phenol resin), 0.5 parts of Unifiner W-575 (manufactured by Unitika Corporation, active ester compound), 0.5 parts of G4-142MHR (manufactured by Nippon Kayaku Co., Ltd., carboxylic acid compound), 2.5 parts of MIR-3000-70MT (manufactured by Nippon Kayaku Co., Ltd., maleimide compound), 2.5 parts of MIZ-001 (manufactured by Nippon Kayaku Co., Ltd., maleimide compound), 0.5 parts of phenylmaleimide (manufactured by Tokyo Chemical Industry Co., Ltd., maleimide compound), 0.5 parts of SYTESTER TA (manufactured by Mitsubishi Gas Chemical Company, bisphenol A type cyanate resin), 60 parts of OPE-2st 2200 (manufactured by Mitsubishi Gas Chemical Company, polyphenylene ether compound), 3 parts of a compound having an ethylenically unsaturated bond as described in WO2021 / 100658, KAYARAD 1 part R-684 (manufactured by Nippon Kayaku Co., Ltd., compound having an ethylenically unsaturated bond), 0.5 parts acenaphthylene (manufactured by Tokyo Chemical Industry Co., Ltd., compound having an ethylenically unsaturated bond), 1 part compound having a polyimide structure as described in WO2023 / 013224A1, 1 part TAIC: triallyl isocyanurate (manufactured by Mitsubishi Chemical Corporation, allyl compound), 1 part Septon 2104 (manufactured by Kuraray Co., Ltd., polystyrene modified product), 1 part benzoxazine Pd (manufactured by Shikoku Chemicals Co., Ltd., benzoxazine compound), 0.5 parts 2E4MZ: 2-ethyl-4-methylimidazole (manufactured by Shikoku Chemicals Co., Ltd., curing accelerator), 0.5 parts TPP: triphenylphosphine (manufactured by Hokko Chemical Co., Ltd., curing accelerator), 0.1 parts Octop Zn (manufactured by Hope Pharmaceutical Co., Ltd., curing accelerator), Sun-Aid 0.1 parts of SI-B5 (manufactured by Sanshin Chemical Co., Ltd., curing accelerator), 1 part of DCP: dicumyl peroxide (manufactured by Kayaku Nurion Co., Ltd., polymerization initiator), 99.2 parts of toluene as solvent, and 49 parts of tetrahydrofuran.By mixing the ingredients in a 6:1 ratio and heating them under a nitrogen atmosphere at 110°C for 10 minutes, then at 220°C for 1 hour, a cured product was obtained.

[0133] [Reference example 2] Compound (E1) obtained in Example 2 was mixed in the following proportions: 20 parts, NC-3000 (manufactured by Nippon Kayaku Co., Ltd., biphenyl aralkyl type epoxy resin), 10 parts, MIZ-001 (manufactured by Nippon Kayaku Co., Ltd., maleimide compound), 5 parts, compound having an ethylenically unsaturated bond as described in WO2021 / 100658, 45 parts, KAYARAD R-684 (manufactured by Nippon Kayaku Co., Ltd., compound having an ethylenically unsaturated bond), 1 part, Irgacure OXE-04 (manufactured by BASF, polymerization initiator), and 1 part, Irgacure 290 (manufactured by BASF, polymerization initiator). This mixture was coated onto a PET film to a thickness of 100 μm, and a PET film was attached to the side not in contact with the film. The mixture was then subjected to a high-pressure mercury lamp (365 nm) at a pressure of 3000 mJ / cm². 2 By irradiating it with ultraviolet light, a cured product could be obtained.

[0134] The epoxy resin of the present invention is suitably used in electrical and electronic components such as semiconductor encapsulants, printed circuit boards, build-up laminates, and optical waveguide devices.

Claims

1. A curable resin composition comprising an epoxy resin represented by the following formula (1) and a reactive compound. 【Chemistry 1】 (In formula (1), each of the multiple R groups exists independently and represents a hydrocarbon group with 1 to 5 carbon atoms. In each benzene ring substituted with R, the sum of the carbon atoms of the multiple R groups is between 2 and 8. k is an integer between 1 and 4. n is the average number of repeats, between 1 and 20.)

2. The curable resin composition according to claim 1, wherein the reactive compound is at least one selected from the group consisting of epoxy resins other than the epoxy resin represented by formula (1), amine compounds, amide compounds, acid anhydride compounds, phenolic resins, active ester compounds, carboxylic acid compounds, maleimide compounds, cyanate compounds, isocyanate compounds, polyphenylene ether compounds, compounds having ethylenically unsaturated bonds, polyamide compounds, polyimide compounds, allyl compounds, polybutadiene and modified thereof, polystyrene and modified thereof, polyethylene and modified thereof, and benzoxazine compounds.

3. The curable resin composition according to claim 1, further comprising an inorganic filler.

4. The curable resin composition according to claim 1, further comprising a curing accelerator.

5. A cured product obtained by curing the curable resin composition according to any one of claims 1 to 4.

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