resin composition

Abstract

To provide a resin composition that yields a cured product with excellent mechanical strength and a relatively low dielectric constant.SOLUTION: A resin composition contains (A) an inorganic filler, wherein the component (A) includes (A-1) a hollow inorganic filler with an average sphericity of 0.6 or more and an average particle size of 5 μm or less. The dielectric loss tangent (Df) of the cured resin composition is 0.010 or less, as measured at 5.8 GHz and 23°C, and the relative dielectric constant (Dk) of the cured resin composition is 3.0 or less, as measured at 5.8 GHz and 23°C.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a resin composition containing an epoxy resin. Furthermore, it relates to a cured product, a sheet-like laminated material, a resin sheet, a printed circuit board, and a semiconductor device obtained using the resin composition. [Background technology]

[0002] As a manufacturing technology for printed circuit boards, a build-up method is known in which insulating layers and conductive layers are stacked alternately. In the build-up method, the insulating layer in a printed circuit board is generally formed by curing a resin composition. In recent years, in order to improve the performance of electronic components, it has become necessary to keep the dielectric constant of the insulating layer even lower than before. One method for keeping the dielectric constant low is the use of hollow inorganic filler particles (Patent Document 1 or 2). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-83966 [Patent Document 2] Patent No. 5864299 [Overview of the project] [Problems that the invention aims to solve]

[0004] Previously, it was known that using small-diameter hollow inorganic filler particles with an average particle size of 5 μm or less could lower the dielectric constant, but a challenge with using such particles was the resulting decrease in mechanical strength.

[0005] The object of the present invention is to provide a resin composition that can produce a cured product with excellent mechanical strength and a low dielectric constant. [Means for solving the problem]

[0006] The inventors have previously discovered that when conventional hollow inorganic particles (hollow inorganic fillers) with an average particle size of 5 μm or less and low average circularity are used in a resin composition, pressure localizes to the convex parts of the particles during the kneading process to disperse the resin composition before curing, causing the hollow inorganic particles to break. The resulting fragments of hollow inorganic particles then become the starting point for breakage, reducing the mechanical strength of the cured product. Therefore, in order to achieve the objectives of the present invention, the inventors manufactured (A-1) hollow inorganic fillers with an average circularity of 0.6 or more and an average particle size of 5 μm or less, and by using these as (A) inorganic fillers in a resin composition, they succeeded in obtaining a cured product with excellent mechanical strength and a low dielectric constant, thus completing the present invention.

[0007] In other words, the present invention includes the following: [1] (A) A resin composition containing an inorganic filler, (A) Component (A-1) includes a hollow inorganic filler having an average circularity of 0.6 or more and an average particle size of 5 μm or less, The dielectric loss tangent (Df) of the cured resin composition is 0.010 or less when measured at 5.8 GHz and 23°C, and A resin composition in which the relative permittivity (Dk) of the cured product is 3.0 or less when measured at 5.8 GHz and 23°C. [2] The resin composition according to [1] above, wherein the content of component (A) is 40% by mass or more when the nonvolatile components in the resin composition are taken as 100% by mass. [3] The resin composition according to [1] above, wherein the average particle size of component (A-1) is 0.3 μm or more. [4] The resin composition according to [1] above, wherein the porosity of component (A-1) is 15% by volume or more. [5] The resin composition according to [1] above, wherein the material forming component (A-1) is silica. [6] The resin composition according to [1] above, wherein the content of component (A-1) is 30% by mass or more when the total amount of component (A) in the resin composition is 100% by mass. [7] The resin composition according to [1] above, further comprising an epoxy resin. [8] The resin composition according to [1] above, further comprising a curing agent. [9] The resin composition according to [8] above, wherein component (C) contains an active ester-based curing agent.

[10] The resin composition according to [8] above, wherein component (C) contains a naphthalene-type active ester-based curing agent.

[11] The resin composition according to [8] above, wherein component (C) contains a phenolic curing agent.

[12] The resin composition according to [1] above, further comprising a thermoplastic resin.

[13] The resin composition according to

[12] above, wherein component (D) contains a phenoxy resin.

[14] The resin composition according to [1] above, wherein the elongation at break of the cured product of the resin composition is 1.0% or more when measured at 23°C.

[15] The resin composition according to [1] above, wherein the linear thermal expansion coefficient of the cured product of the resin composition is 30 ppm / °C or less.

[16] A cured product of the resin composition according to any one of [1] to

[15] above.

[17] A sheet-like laminated material containing the resin composition according to any one of [1] to

[15] above.

[18] A resin sheet having a support and a resin composition layer formed from the resin composition according to any one of [1] to

[15] above provided on the support.

[19] A printed wiring board provided with an insulating layer made of a cured product of the resin composition according to any one of [1] to

[15] above.

[20] A semiconductor device including the printed wiring board according to

[19] above. [Effect of the Invention]

[0008] According to the resin composition of the present invention, a cured product having excellent mechanical strength and a low relative permittivity can be obtained. [Embodiments for Carrying Out the Invention]

[0009] The present invention will be described in detail below with reference to its preferred embodiments. However, the present invention is not limited to the embodiments and examples described below, and can be implemented with modifications as appropriate without departing from the scope of the claims and equivalents of the present invention.

[0010] <Resin composition> The resin composition of the present invention comprises (A) an inorganic filler, wherein (A) the inorganic filler comprises (A-1) a hollow inorganic filler having an average circularity of 0.6 or more and an average particle size of 5 μm or less. By using such a resin composition, a cured product with excellent mechanical strength and a low dielectric constant can be obtained. The dielectric loss tangent (Df) of the cured product of the resin composition is 0.010 or less when measured at 5.8 GHz and 23°C, and the dielectric constant (Dk) of the cured product of the resin composition is 3.0 or less when measured at 5.8 GHz and 23°C.

[0011] The resin composition of the present invention may further contain (A) an inorganic filler and any other resin component. The resin component is not particularly limited, but examples include (B) epoxy resin, (C) curing agent, (D) thermoplastic resin, (E) curing accelerator, (F) other additives, and (G) organic solvent. Each component that may be included in the resin composition will be described in detail below.

[0012] <(A) Inorganic filler> The resin composition of the present invention contains (A) an inorganic filler. (A) The inorganic filler is included in the resin composition in the form of particles. Examples of (A) the inorganic filler include hollow inorganic fillers having voids inside the particles (porosity > 0 volume%) and non-hollow inorganic fillers not having voids inside the particles (porosity = 0 volume%).

[0013] In the resin composition of the present invention, (A) the inorganic filler includes (A-1) a hollow inorganic filler having an average circularity of 0.6 or more and an average particle size of 5 μm or less (hereinafter sometimes referred to as "specific hollow inorganic filler"). (A-1) The specific hollow inorganic filler may be used alone, or two or more types may be used in any ratio.

[0014] (A-1) Examples of materials for forming the specific hollow inorganic filler include silica, alumina, aluminosilicate, and among these, silica is preferred.

[0015] (A-1) The average circularity of the specified hollow inorganic filler is 0.6 or higher, preferably 0.65 or higher, and more preferably 0.68 or higher. (A-1) The upper limit of the average circularity of the specified hollow inorganic filler may be, for example, 1 or less. (A-1) The average circularity of the specified hollow inorganic filler is the average value of the circularity φ of the particles of the (A-1) specified hollow inorganic filler. Circularity φ is defined as the ratio of the perimeter of a perfect circle with an area equal to the projected area of ​​the particle in the particle shape image analysis to the actual perimeter of the particle (perimeter of a perfect circle with the same area as the particle / actual perimeter of the particle), for example, the projected area S(m²) of the particle in the image obtained from the particle shape image analysis. 2 It is calculated using the following formula (1) with respect to the perimeter L (m) of the particles in the image.

[0016]

number

[0017] (A-1) The average particle size of the specified hollow inorganic filler is 5.0 μm or less, preferably 4.0 μm or less, more preferably 3.0 μm or less, even more preferably 2.5 μm or less, and particularly preferably 2.2 μm or less, from the viewpoint of obtaining the desired effects of the present invention more significantly. (A-1) The lower limit of the average particle size of the specified hollow inorganic filler is preferably 0.3 μm or more, preferably 0.5 μm or more. The average particle size of the inorganic filler can be measured by the laser diffraction-scattering method based on Mie scattering theory. Specifically, the particle size distribution of the inorganic filler can be created on a volume basis using a laser diffraction-scattering particle size distribution analyzer, and the average particle size can be measured by taking the median diameter as the average particle size. A sample can be used in which 100 mg of inorganic filler and 10 g of methyl ethyl ketone are weighed into a vial and dispersed by ultrasound for 10 minutes. The particle size distribution of the inorganic filler was measured using a laser diffraction particle size distribution analyzer with blue and red light source wavelengths, employing a flow cell method. The average particle size was calculated as the median diameter from the obtained particle size distribution. Examples of laser diffraction particle size distribution analyzers include the "LA-960" manufactured by Horiba, Ltd.

[0018] (A-1) The specific surface area of ​​the specified hollow inorganic filler is not particularly limited, but is preferably 60 m². 2 / g or less, more preferably 40m 2 / g or less, more preferably 20m 2 / g or less, particularly preferably 15m 2 It is less than / g. (A-1) The lower limit of the specific surface area of ​​the specified hollow inorganic filler is not particularly limited, but for example, 1m 2 The value is 1 / g or more. The specific surface area of ​​the inorganic filler is obtained by adsorbing nitrogen gas onto the sample surface using a specific surface area measuring device (Macsorb HM-1210, manufactured by Mountec Co., Ltd.) according to the BET method, and then calculating the specific surface area using the BET multipoint method.

[0019] (A-1) The specific hollow inorganic filler has pores inside the particles. (A-1) The specific hollow inorganic filler may be single hollow particles having only one pore inside the particles, multi-hollow particles having two or more pores inside the particles, or a mixture thereof.

[0020] (A-1) From the viewpoint of further suppressing the relative permittivity, the porosity of the specific hollow inorganic filler is preferably 15% by volume or more, more preferably 30% by volume or more, still more preferably 45% by volume or more, even more preferably 60% by volume or more, particularly preferably 75% by volume or more. The upper limit thereof may be preferably 90% by volume or less, more preferably 85% by volume or less from the viewpoint of further improving the mechanical strength. The porosity P (% by volume) of the inorganic filler is defined as the volume-based ratio (total volume of pores / volume of particles) of the total volume of one or two or more pores existing inside the particles to the total volume of the particles based on the outer surface of the particles. For example, the measured value D of the actual density of the inorganic filler M (g / cm 3 ) and the theoretical value D of the material density of the material forming the inorganic filler T (g / cm 3 ) are used and calculated by the following formula (2).

[0021]

Equation

[0022] (A-1) A commercially available product may be used for the specific hollow inorganic filler, or it may be manufactured by a known method or a method analogous thereto. Examples of commercially available products of the specific hollow inorganic filler include, for example, "Selfiers", "MGH-005", "MG-005" manufactured by Taiheiyo Cement Corporation; "Esferic", "BA-1", etc. manufactured by JGC Catalysts & Chemicals Ltd. Specific examples of the method for manufacturing the hollow inorganic filler are not particularly limited, but an aqueous solution containing a substance capable of forming pores and a basic compound is prepared, the aqueous solution and an alkoxysilane are mixed and stirred to precipitate silica particles, the substance capable of forming pores is removed from the silica particles to obtain a hollow silica precursor, and the obtained hollow silica precursor can be used by a method of firing.

[0023] (A-1) The specific hollow inorganic filler is preferably heat-treated on its surface. The conditions for the surface heat treatment are not particularly limited, but from the viewpoint of suppressing fracture (cracking) due to collisions between particles, the treatment temperature is, for example, in the range of 50°C to 100°C, preferably 70°C to 80°C, and the treatment time is, for example, in the range of 0.5 hours to 3 hours, preferably 1 hour to 3 hours.

[0024] (A-1) The specified hollow inorganic filler is preferably treated with a surface treatment agent from the viewpoint of improving moisture resistance and dispersibility. The surface treatment is preferably carried out simultaneously with the heat treatment described above. Examples of surface treatment agents include fluorine-containing silane coupling agents, aminosilane coupling agents, epoxysilane coupling agents, mercaptosilane coupling agents, silane coupling agents, alkoxysilanes, organosilazane compounds, titanate coupling agents, etc. Furthermore, the surface treatment agent may be used alone or in any combination of two or more types.

[0025] Examples of commercially available surface treatment agents include "KBM403" (3-glycidoxypropyltrimethoxysilane), "KBM803" (3-mercaptopropyltrimethoxysilane), "KBE903" (3-aminopropyltriethoxysilane), "KBM573" (N-phenyl-3-aminopropyltrimethoxysilane), "SZ-31" (hexamethyldisilazane), "KBM103" (phenyltrimethoxysilane), "KBM-4803" (long-chain epoxy-type silane coupling agent), and "KBM-7103" (3,3,3-trifluoropropyltrimethoxysilane), all manufactured by Shin-Etsu Chemical Co., Ltd.

[0026] The degree of surface treatment with the surface treatment agent is preferably within a predetermined range from the viewpoint of improving the dispersibility of the specified hollow inorganic filler (A-1). Specifically, it is preferable that the surface is treated with 0.2% to 5% by mass of the surface treatment agent per 100% by mass of the specified hollow inorganic filler (A-1), more preferably 0.2% to 3% by mass, and even more preferably 0.3% to 2% by mass.

[0027] The degree of surface treatment by a surface treatment agent can be evaluated by the amount of carbon per unit surface area of ​​the inorganic filler. (A-1) The amount of carbon per unit surface area of ​​a specific hollow inorganic filler is 0.02 mg / m² from the viewpoint of improving the dispersibility of the inorganic filler. 2 The above is preferred, and 0.1 mg / m² 2 The above is more preferable, 0.2 mg / m² 2 The above is even more preferable. On the other hand, from the viewpoint of preventing an increase in the melt viscosity of the resin composition and the melt viscosity in sheet form, 1.0 mg / m² 2 The following is preferred: 0.8 mg / m² 2 The following is more preferable: 0.5 mg / m² 2 The following is even more preferable. The amount of carbon per unit surface area of ​​the inorganic filler can be measured after washing the inorganic filler with a solvent (e.g., methyl ethyl ketone (MEK)) after surface treatment. Specifically, a sufficient amount of MEK as the solvent is added to the inorganic filler that has been surface-treated with a surface treatment agent, and ultrasonic cleaning is performed at 25°C for 5 minutes. After removing the supernatant and drying the solids, the amount of carbon per unit surface area of ​​the inorganic filler can be measured using a carbon analyzer. As a carbon analyzer, the "EMIA-320V" manufactured by Horiba, Ltd. can be used.

[0028] The content of (A-1) specific hollow inorganic filler in the resin composition is not particularly limited, but when the nonvolatile components in the resin composition are taken as 100% by mass, it is preferably 90% by mass or less, more preferably 85% by mass or less, and most preferably 80% by mass or less. The lower limit of the content of (A-1) specific hollow inorganic filler in the resin composition is not particularly limited, but from the viewpoint of obtaining the desired effects of the present invention more significantly, when the nonvolatile components in the resin composition are taken as 100% by mass, it is preferably 5% by mass or more, more preferably 10% by mass or more, and most preferably 15% by mass or more, and from the viewpoint of keeping the dielectric loss tangent of the cured product lower, it is even more preferably 20% by mass or more, even more preferably 30% by mass or more, and most preferably 40% by mass or more.

[0029] The content of (A-1) specific hollow inorganic filler relative to the total (A) inorganic filler is not particularly limited, but from the viewpoint of obtaining the desired effects of the present invention more significantly, when the total (A) inorganic filler in the resin composition is taken as 100% by mass, it is preferably 10% by mass or more, more preferably 20% by mass or more, and particularly preferably 30% by mass or more, and from the viewpoint of keeping the dielectric loss tangent of the cured product lower, it is even more preferably 40% by mass or more, even more preferably 50% by mass or more, and most preferably 60% by mass or more, and the upper limit is not particularly limited, but may be 99% by mass or less, 95% by mass or less, 90% by mass or less, 80% by mass or less, etc.

[0030] In the resin composition of the present invention, (A) inorganic filler may further contain (A-2) non-hollow inorganic filler as an optional component. When (A-2) non-hollow inorganic filler is included, (A-2) non-hollow inorganic filler may be used alone or two or more types may be used in any ratio.

[0031] (A-2) Inorganic compounds are used as the material for the non-hollow inorganic filler. (A-2) Examples of materials for the non-hollow inorganic filler include silica, alumina, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, 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, and zirconium tungstate phosphate. Among these, silica is particularly preferred. Examples of silica include amorphous silica, fused silica, crystalline silica, and synthetic silica. Furthermore, spherical silica is preferred for the (A-2) non-hollow inorganic filler.

[0032] (A-2) Examples of commercially available non-hollow inorganic fillers include "SP60-05" and "SP507-05" from Nippon Steel Chemical & Material Co., Ltd.; "YC100C", "YA050C", "YA050C-MJE", "YA010C", "SC2500SQ", "SO-C4", "SO-C2", and "SO-C1" from Admatex Co., Ltd.; "UFP-30", "DAW-03", and "FB-105FD" from Denka Co., Ltd.; and "Silfil NSS-3N", "Silfil NSS-4N", and "Silfil NSS-5N" from Tokuyama Corporation.

[0033] (A-2) The average particle size of the non-hollow inorganic filler is not particularly limited, but is preferably 10 μm or less, more preferably 5 μm or less, even more preferably 3 μm or less, even more preferably 2 μm or less, and particularly preferably 1.5 μm or less. (A-2) The lower limit of the average particle size of the non-hollow inorganic filler is not particularly limited, but is preferably 0.01 μm or more, more preferably 0.05 μm or more, even more preferably 0.1 μm or more, and particularly preferably 0.2 μm or more.

[0034] (A-2) The specific surface area of ​​the non-hollow inorganic filler is not particularly limited, but is preferably 0.1 m². 2 / g or more, more preferably 0.5m 2 / g or more, more preferably 1m 2 / g or more, particularly preferably 3m 2 (A-2) The upper limit of the specific surface area of ​​the non-hollow inorganic filler is not particularly limited, but preferably 100 m². 2 / g or less, more preferably 70m 2 / g or less, more preferably 50m 2 / g or less, and more preferably 30m 2 / g or less, particularly preferably 10m 2 It is less than / g.

[0035] (A-2) The average circularity of the non-hollow inorganic filler is preferably 0.4 or higher, preferably 0.5 or higher, preferably 0.6 or higher, and preferably 0.65 or higher. (A-2) The upper limit of the average circularity of the non-hollow inorganic filler may be, for example, 1 or less.

[0036] (A-2) The non-hollow inorganic filler is preferably treated with a surface treatment agent from the viewpoint of improving moisture resistance and dispersibility. As the surface treatment agent, the same as those listed above can be used as for (A-1) the specified hollow inorganic filler. The degree of surface treatment by the surface treatment agent and the amount of carbon per unit surface area may be the same as for (A-1) the specified hollow inorganic filler.

[0037] The content of (A-2) non-hollow inorganic filler in the resin composition is not particularly limited, but when the non-volatile components in the resin composition are taken as 100% by mass, it is preferably 80% by mass or less, more preferably 70% by mass or less, even more preferably 60% by mass or less, even more preferably 50% by mass or less, and particularly preferably 40% by mass or less, and from the viewpoint of keeping the dielectric loss tangent of the cured product even lower, it may be 30% by mass or less. The lower limit of the content of (A-2) non-hollow inorganic filler in the resin composition is not particularly limited, but when the non-volatile components in the resin composition are taken as 100% by mass, for example, it is 0% by mass or more, 1% by mass or more, preferably 5% by mass or more, and more preferably 10% by mass or more.

[0038] The content of (A-2) non-hollow inorganic filler relative to the total (A) inorganic filler is not particularly limited, but from the viewpoint of obtaining the desired effects of the present invention more significantly, when the total (A) inorganic filler in the resin composition is taken as 100% by mass, it is preferably 90% by mass or less, more preferably 80% by mass or less, and particularly preferably 70% by mass or less, and from the viewpoint of keeping the dielectric loss tangent of the cured product lower, it is even more preferably 60% by mass or less, even more preferably 50% by mass or less, and most preferably 40% by mass or less, and the lower limit is not particularly limited, but may be 1% by mass or more, 5% by mass or more, 10% by mass or more, 20% by mass or more, etc.

[0039] The content of inorganic filler (A) in the resin composition is not particularly limited, but when the non-volatile components in the resin composition are taken as 100% by mass, it is preferably 90% by mass or less, more preferably 80% by mass or less, even more preferably 75% by mass or less, and particularly preferably 70% by mass or less. The lower limit of the content of inorganic filler (A) in the resin composition is not particularly limited, but from the viewpoint of keeping the dielectric loss tangent and relative permittivity lower, when the non-volatile components in the resin composition are taken as 100% by mass, it is preferably 30% by mass or more, more preferably 40% by mass or more, even more preferably 50% by mass or more, and particularly preferably 60% by mass or more.

[0040] <(B) Epoxy resin> The resin composition of the present invention may further contain (B) epoxy resin as an optional component. (B) epoxy resin is a curable resin having epoxy groups in an epoxy equivalent of 5,000 g / eq. or less.

[0041] (B) Examples of epoxy resins include bixylenol-type epoxy resin, bisphenol A-type epoxy resin, bisphenol F-type epoxy resin, bisphenol S-type epoxy resin, bisphenol AF-type epoxy resin, dicyclopentadiene-type epoxy resin, trisphenol-type epoxy resin, naphthol novolac-type epoxy resin, phenol novolac-type epoxy resin, tert-butyl-catechol-type epoxy resin, naphthalene-type epoxy resin, naphthol-type epoxy resin, anthracene-type epoxy resin, glycidylamine-type epoxy resin, glycidyl ester-type epoxy resin, cresol novolac-type epoxy resin, phenol aralkyl-type epoxy resin, biphenyl-type epoxy resin, linear aliphatic epoxy resin, epoxy resin having a butadiene structure, alicyclic epoxy resin, heterocyclic epoxy resin, spiro-ring-containing epoxy resin, cyclohexane-type epoxy resin, cyclohexanedimethanol-type epoxy resin, naphthylene ether-type epoxy resin, trimethylol-type epoxy resin, tetraphenylethane-type epoxy resin, isocyanurate-type epoxy resin, phenolphthaleimidine-type epoxy resin, and the like. (B) Epoxy resin may be used alone or in combination of two or more types.

[0042] The resin composition preferably contains an epoxy resin having two or more epoxy groups per molecule as (B) epoxy resin. The proportion of epoxy resin having two or more epoxy groups per molecule relative to 100% by mass of the nonvolatile component of (B) epoxy resin is preferably 50% by mass or more, more preferably 60% by mass or more, and particularly preferably 70% by mass or more.

[0043] Epoxy resins include epoxy resins that are liquid at 20°C (hereinafter sometimes referred to as "liquid epoxy resins") and epoxy resins that are solid at 20°C (hereinafter sometimes referred to as "solid epoxy resins"). The resin composition of the present invention may contain only liquid epoxy resin, only solid epoxy resin, or a combination of liquid epoxy resin and solid epoxy resin, but it is preferable to contain a combination of liquid epoxy resin and solid epoxy resin.

[0044] As the liquid epoxy resin, a liquid epoxy resin having two or more epoxy groups in one molecule is preferred.

[0045] Preferred liquid epoxy resins include glycirol-type epoxy resins, bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, bisphenol AF-type epoxy resins, naphthalene-type epoxy resins, glycidyl ester-type epoxy resins, glycidylamine-type epoxy resins, phenol novolac-type epoxy resins, alicyclic epoxy resins having an ester skeleton, cyclohexanedimethanol-type epoxy resins, cyclic aliphatic glycidyl ethers, and epoxy resins having a butadiene structure.

[0046] Specific examples of liquid epoxy resins include "EX-992L" from Nagase ChemteX, "YX7400" from Mitsubishi Chemical Corporation, "HP4032", "HP4032D", and "HP4032SS" from DIC Corporation (naphthalene-type epoxy resin); "828US", "828EL", "825", and "Epicote 828EL" from Mitsubishi Chemical Corporation (bisphenol A-type epoxy resin); and "jER807" and "1750" from Mitsubishi Chemical Corporation (bisphenol F-type epoxy resin). Xylionic resin); "jER152" (phenol novolac type epoxy resin) manufactured by Mitsubishi Chemical Corporation; "630", "630LSD", "604" (glycidylamine type epoxy resin) manufactured by Mitsubishi Chemical Corporation; "ED-523T" (glycyrol type epoxy resin) manufactured by ADEKA Corporation; "EP-3950L", "EP-3980S" (glycidylamine type epoxy resin) manufactured by ADEKA Corporation; "EP-4088S" (dicyclopentadiene type epoxy resin) manufactured by ADEKA Corporation; "ZX1059" (mixture of bisphenol A type epoxy resin and bisphenol F type epoxy resin) manufactured by Nippon Steel Chemical & Material Corporation; "EX-721" (glycidyl ester type epoxy resin) manufactured by Nagase ChemteX Corporation; "EX-991L" (epoxy resin containing alkylene oxy skeleton and butadiene skeleton) manufactured by Nagase ChemteX Corporation; "Celoxide 2021P" (alicyclic epoxy resin with ester skeleton) manufactured by Daicel Corporation; Daicel Corporation Examples include "PB-3600," "JP-100," "JP-200," and "JP-400" (epoxy resins with a butadiene structure) from Nippon Soda Co., Ltd.; "ZX1658" and "ZX1658GS" (liquid 1,4-glycidylcyclohexane type epoxy resins) from Nippon Steel Chemical & Material Co., Ltd.; "EG-280" (fluorene structure-containing epoxy resin) from Osaka Gas Chemical Co., Ltd.; and "EX-201" (cyclic aliphatic glycidyl ether) from Nagase ChemteX Corporation.

[0047] As the solid epoxy resin, a solid epoxy resin having three or more epoxy groups per molecule is preferred, and an aromatic solid epoxy resin having three or more epoxy groups per molecule is more preferred.

[0048] Preferred solid epoxy resins include bixylenol-type epoxy resin, naphthalene-type epoxy resin, naphthalene-type tetrafunctional epoxy resin, naphthol novolac-type 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, phenol aralkyl-type epoxy resin, tetraphenylethane-type epoxy resin, and phenolphthaleimidine-type epoxy resin.

[0049] Specific examples of solid epoxy resins include DIC's "HP4032H" (naphthalene-type epoxy resin); DIC's "HP-4700" and "HP-4710" (naphthalene-type tetrafunctional epoxy resins); DIC's "N-690" (cresol novolac-type epoxy resin); DIC's "N-695" (cresol novolac-type epoxy resin); DIC's "HP-7200", "HP-7200HH", "HP-7200H", and "HP-7200L" (dicyclopentadiene-type epoxy resins); DIC's "EXA-7311" and "E XA-7311-G3, EXA-7311-G4, EXA-7311-G4S, HP6000, HP6000L (naphthylene ether type epoxy resin); Nippon Kayaku Co., Ltd.'s "EPPN-502H" (trisphenol type epoxy resin); Nippon Kayaku Co., Ltd.'s "NC7000L" (naphthol novolac type epoxy resin); Nippon Kayaku Co., Ltd.'s "NC3000H", "NC3000", "NC3000L", "NC3000FH", "NC3100" (biphenyl type epoxy resin); Nippon Steel Chemical & Material Co., Ltd.'s "ESN475V", "ESN4100V" (naphthalene-type epoxy resin); "ESN485" (naphthol-type epoxy resin) manufactured by Nippon Steel Chemical & Material Co., Ltd.; "ESN375" (dihydroxynaphthalene-type epoxy resin) manufactured by Nippon Steel Chemical & Material Co., Ltd.; "YX4000H", "YX4000", "YX4000HK", "YL7890" (bixylenol-type epoxy resin) manufactured by Mitsubishi Chemical Corporation; "YL6121" (biphenyl-type epoxy resin) manufactured by Mitsubishi Chemical Corporation; "YX8800" (anthracene-type epoxy resin) manufactured by Mitsubishi Chemical Corporation; Examples include "YX7700" (phenol aralkyl type epoxy resin); "PG-100" and "CG-500" from Osaka Gas Chemical Co., Ltd.; "YX7760" (bisphenol AF type epoxy resin) from Mitsubishi Chemical Corporation; "YL7800" (fluorene type epoxy resin) from Mitsubishi Chemical Corporation; "jER1010" (bisphenol A type epoxy resin) from Mitsubishi Chemical Corporation; "jER1031S" (tetraphenylethane type epoxy resin) from Mitsubishi Chemical Corporation; and "WHR991S" (phenolphthalein-imidine type epoxy resin) from Nippon Kayaku Co., Ltd.These may be used individually or in combination of two or more types.

[0050] (B) When using a combination of solid epoxy resin and liquid epoxy resin as the epoxy resin, the mass ratio of the solid epoxy resin to the liquid epoxy resin is preferably 10:1 to 1:50, more preferably 2:1 to 1:20, and particularly preferably 1.5:1 to 1:10.

[0051] (B) The epoxy equivalent of the epoxy resin is preferably 50 g / eq. to 5,000 g / eq., more preferably 60 g / eq. to 2,000 g / eq., even more preferably 70 g / eq. to 1,000 g / eq., and even more preferably 80 g / eq. to 500 g / eq. The epoxy equivalent is the mass of resin per equivalent of epoxy groups. This epoxy equivalent can be measured according to JIS K7236.

[0052] (B) The weight-average molecular weight (Mw) of the epoxy resin is preferably 100 to 5,000, more preferably 250 to 3,000, and even more preferably 400 to 1,500. The weight-average molecular weight of the resin can be measured as a polystyrene equivalent by gel permeation chromatography (GPC).

[0053] The content of epoxy resin (B) in the resin composition is not particularly limited, but when the nonvolatile components in the resin composition are taken as 100% by mass, it is preferably 50% by mass or less, more preferably 45% by mass or less, even more preferably 40% by mass or less, even more preferably 35% by mass or less, and particularly preferably 30% by mass or less. The lower limit of the content of epoxy resin (B) in the resin composition is not particularly limited, but when the nonvolatile components in the resin composition are taken as 100% by mass, for example, it is 0% by mass or more, 0.01% by mass or more, 0.1% by mass or more, preferably 0.5% by mass or more, more preferably 1% by mass or more, even more preferably 5% by mass or more, even more preferably 10% by mass or more, and particularly preferably 15% by mass or more.

[0054] The mass ratio of (A) inorganic filler to (B) epoxy resin in the resin composition (component (A) / component (B)) is not particularly limited, but from the viewpoint of obtaining the desired effects of the present invention more significantly, it is preferably 0.1 or more, more preferably 0.5 or more, and even more preferably 1 or more. The upper limit of the mass ratio of (A) inorganic filler to (B) epoxy resin in the resin composition (component (A) / component (B)) is not particularly limited, but it is more preferably 50 or less, even more preferably 10 or less, and particularly preferably 5 or less.

[0055] <(C) Hardener> The resin composition of the present invention may further contain (C) a curing agent as an optional component. (C) The curing agent may be used alone or in any combination of two or more types. (C) The curing agent may have the function of reacting with (B) epoxy resin to cure it.

[0056] (C) The curing agent is not particularly limited, but examples include active ester curing agents, phenol curing agents, carbodiimide curing agents, acid anhydride curing agents, amine curing agents, benzoxazine curing agents, cyanate ester curing agents, and thiol curing agents. (C) The curing agent preferably contains one or more curing agents selected from active ester curing agents and phenol curing agents. (C) The curing agent is particularly preferably made to contain an active ester curing agent from the viewpoint of keeping the dielectric loss tangent lower. Furthermore, (C) the curing agent is particularly preferably made to contain a phenol curing agent from the viewpoint of further improving curability.

[0057] As active ester curing agents, 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, are generally preferred. The active ester compound is preferably obtained by a condensation reaction between a carboxylic acid compound and / or a thiocarboxylic acid compound and a hydroxy compound and / or a thiol compound. Particularly from the viewpoint of improving heat resistance, an active ester compound obtained from a carboxylic acid compound and a hydroxy compound is preferred, and an active ester compound obtained from a carboxylic acid compound and / or a naphthol compound is more preferred. Examples of carboxylic acid compounds include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, and pyromellitic acid. Examples of phenol compounds or 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, and phenol novolac. Here, "dicyclopentadiene-type diphenol compounds" refers to diphenol compounds obtained by the condensation of two phenol molecules with one dicyclopentadiene molecule.

[0058] As the active ester curing agent, specifically, dicyclopentadiene-type active ester curing agents (active ester compounds containing a dicyclopentadiene-type diphenol structure), naphthalene-type active ester curing agents (active ester compounds containing a naphthalene structure), and phenol novolac-type active ester curing agents (active ester compounds containing a phenol novolac structure (such as acetylated or benzoylated compounds)) are preferred, and among these, at least one selected from dicyclopentadiene-type active ester curing agents and naphthalene-type active ester curing agents is more preferred, and from the viewpoint of further suppressing the dielectric loss tangent of the cured product, the naphthalene-type active ester curing agent is even more preferred. In one embodiment of the present invention, an embodiment in which a dicyclopentadiene-type active ester curing agent and a naphthalene-type active ester curing agent are used in combination is also preferred.

[0059] Commercially available active ester curing agents include active ester compounds containing a dicyclopentadiene-type diphenol structure, such as "EXB9451," "EXB9460," "EXB9460S," "HPC-8000L-65TM," "HPC-8000-65T," "HPC-8000H," and "HPC-8000H-65TM" (manufactured by DIC Corporation); and active ester compounds containing a naphthalene structure, such as "HP-B-8151-62T," "EXB-8100L-65T," "EXB-9416-70BK," and "HPC-8150-62T." Examples include "EXB-8" (manufactured by DIC Corporation), "EXB9401" (manufactured by DIC Corporation) as a phosphorus-containing active ester compound, "DC808" (manufactured by Mitsubishi Chemical Corporation) as an acetylated active ester compound of phenol novolac, "YLH1026", "YLH1030", and "YLH1048" (manufactured by Mitsubishi Chemical Corporation) as benzoylated active ester compounds of phenol novolac, and "PC1300-02-65MA" (manufactured by Air Water Corporation) as an active ester compound containing a styryl group and a naphthalene structure.

[0060] As a phenolic curing agent, a phenolic curing agent having a novolac structure is preferred from the viewpoint of heat resistance and water resistance. Furthermore, from the viewpoint of adhesion to the adherend, a nitrogen-containing phenolic curing agent is preferred, and a triazine skeleton-containing phenolic curing agent is more preferred. Among these, a triazine skeleton-containing phenol novolac resin is preferred from the viewpoint of highly satisfying heat resistance, water resistance, and adhesion. Specific examples of phenol-based curing agents include, for example, "MEH-7700," "MEH-7810," and "MEH-7851" from Meiwa Kasei Co., Ltd., "NHN," "CBN," and "GPH" from Nippon Kayaku Co., Ltd., "SN-170," "SN-180," "SN-190," "SN-475," "SN-485," "SN-495," "SN-375," and "SN-395" from Nippon Steel Chemical & Material Co., Ltd., and "LA-7052," "LA-7054," "LA-3018," "LA-3018-50P," "LA-1356," "TD2090," and "KA-1160" from DIC Corporation.

[0061] Examples of carbodiimide-based curing agents include curing agents having one or more, preferably two or more, carbodiimide structures in one molecule, such as aliphatic biscarbodiimides like tetramethylene-bis(t-butylcarbodiimide) and cyclohexanebis(methylene-t-butylcarbodiimide); biscarbodiimides like aromatic biscarbodiimides like phenylene-bis(xylylcarbodiimide); and aliphatic polycarbodiimides like polyhexamethylenecarbodiimide, polytrimethylhexamethylenecarbodiimide, polycyclohexylenecarbodiimide, poly(methylenebiscyclohexylenecarbodiimide), and poly(isophoronecarbodiimide). Examples of polycarbodiimides include aromatic polycarbodiimides such as poly(phenylenecarbodiimide), poly(naphthylenecarbodiimide), poly(trylenecarbodiimide), poly(methyldiisopropylphenylenecarbodiimide), poly(triethylphenylenecarbodiimide), poly(diethylphenylenecarbodiimide), poly(triisopropylphenylenecarbodiimide), poly(diisopropylphenylenecarbodiimide), poly(xylylenecarbodiimide), poly(tetramethylxylylenecarbodiimide), poly(methylenediphenylenecarbodiimide), and poly[methylenebis(methylphenylene)carbodiimide].

[0062] Examples of commercially available carbodiimide-based curing agents include "Carbodilite V-02B," "Carbodilite V-03," "Carbodilite V-04K," "Carbodilite V-07," and "Carbodilite V-09" from Nisshinbo Chemical Co., Ltd., and "Stabaczol P," "Stabaczol P400," and "Hycazil 510" from Rhein Chemie Corporation.

[0063] Examples of acid anhydride-based curing agents include curing agents having one or more acid anhydride groups in one molecule, and curing agents having two or more acid anhydride groups in one molecule are preferred. Specific examples of acid anhydride-based curing agents include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic anhydride, hydrogenated methylnadic anhydride, trialkyltetrahydrophthalic anhydride, dodecenyl succinic anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclohexen-1,2-dicarboxylic acid anhydride, trimellitic anhydride, pyromellitic anhydride, and bensophenone tetracarboxylic acid di Examples include anhydrides, biphenyltetracarboxylic acid dianhydride, naphthalenetetracarboxylic acid dianhydride, oxydiphthalic acid dianhydride, 3,3'-4,4'-diphenylsulfonetetracarboxylic acid dianhydride, 1,3,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-C]furan-1,3-dione, ethylene glycol bis(anhydrotrimellitate), and polymer-type acid anhydrides such as styrene-maleic acid resin obtained by copolymerizing styrene and maleic acid. Commercially available acid anhydride-based curing agents include "HNA-100," "MH-700," "MTA-15," "DDSA," and "OSA" from Shin Nippon Rika Co., Ltd., "YH-306" and "YH-307" from Mitsubishi Chemical Corporation, "HN-2200" and "HN-5500" from Hitachi Chemical Co., Ltd., and "EF-30," "EF-40," "EF-60," and "EF-80" from Clay Valley Corporation.

[0064] Examples of amine-based curing agents include curing agents having one or more, preferably two or more, amino groups in one molecule. Examples include aliphatic amines, polyetheramines, alicyclic amines, aromatic amines, and among these, aromatic amines are preferred from the viewpoint of achieving the desired effects of the present invention. The amine-based curing agent is preferably a primary amine or a secondary amine, and more preferably a primary amine. Specific examples of amine-based curing agents include 4,4'-methylenebis(2,6-dimethylaniline), 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, m-phenylenediamine, m-xylylenediamine, diethyltoluenediamine, 4,4'-diaminodiphenyl ether, 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dihydroxybenzidine, and 2,2-bis(3-amino-4-hydroxyphenyl) Examples include propyl propane, 3,3-dimethyl-5,5-diethyl-4,4-diphenylmethanediamine, 2,2-bis(4-aminophenyl)propane, 2,2-bis(4-(4-aminophenoxy)phenyl)propane, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, bis(4-(4-aminophenoxy)phenyl)sulfone, bis(4-(3-aminophenoxy)phenyl)sulfone, etc. Amine-based curing agents may be commercially available products, such as "SEIKACURE-S" from Seika Corporation, "KAYABOND C-200S," "KAYABOND C-100," "KAYAHARD AA," "KAYAHARD AB," and "KAYAHARD AS" from Nippon Kayaku Co., Ltd., and "Epicure W" from Mitsubishi Chemical Corporation.

[0065] Specific examples of benzoxazine-based curing agents include "JBZ-OP100D" and "ODA-BOZ" from JFE Chemical Corporation; "HFB2006M" from Showa Polymer Co., Ltd.; and "Pd" and "Fa" from Shikoku Chemicals Co., Ltd.

[0066] Examples of cyanate ester curing agents include bifunctional cyanate resins such as bisphenol A dicyanate, polyphenol cyanate (oligo(3-methylene-1,5-phenylene cyanate)), 4,4'-methylenebis(2,6-dimethylphenyl cyanate), 4,4'-ethylidene diphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis(4-cyanate)phenylpropane, 1,1-bis(4-cyanatephenylmethane), bis(4-cyanate-3,5-dimethylphenyl)methane, 1,3-bis(4-cyanatephenyl-1-(methylethylidene))benzene, bis(4-cyanatephenyl) thioether, and bis(4-cyanatephenyl) ether; polyfunctional cyanate resins derived from phenol novolacs and cresol novolacs; and prepolymers in which these cyanate resins are partially triazined. Specific examples of cyanate ester-based curing agents include "PT30" and "PT60" (both phenol novolac type polyfunctional cyanate ester resins) manufactured by Lonza Japan, "BA230", and "BA230S75" (prepolymers in which part or all of bisphenol A dicyanate is triazined and trimerized).

[0067] Examples of thiol-based curing agents include trimethylolpropane tris(3-mercaptopropionate), pentaerythritol tetrakis(3-mercaptobutyrate), and tris(3-mercaptopropyl) isocyanurate.

[0068] (C) The reactive group equivalent of the curing agent is preferably 50 g / eq. to 3000 g / eq., more preferably 100 g / eq. to 1000 g / eq., even more preferably 100 g / eq. to 500 g / eq., and particularly preferably 100 g / eq. to 300 g / eq. The reactive group equivalent is the mass of (C) curing agent per equivalent of one reactive group.

[0069] The molar ratio (moles of epoxy groups:moles of reactive groups) of the total epoxy groups of (B) epoxy resin and (C) curing agent in the resin composition is preferably in the range of 1:0.2 to 1:2, more preferably in the range of 1:0.3 to 1:1.5, and even more preferably in the range of 1:0.4 to 1:1.

[0070] The content of (C) curing agent in the resin composition is not particularly limited, but when the non-volatile components in the resin composition are taken as 100% by mass, it is preferably 40% by mass or less, more preferably 30% by mass or less, even more preferably 25% by mass or less, and particularly preferably 20% by mass or less. The lower limit of the content of (C) curing agent in the resin composition is not particularly limited, but when the non-volatile components in the resin composition are taken as 100% by mass, it may be, for example, 0% by mass or more, 0.1% by mass or more, or 1% by mass or more, preferably 5% by mass or more, more preferably 8% by mass or more, and particularly preferably 10% by mass or more.

[0071] (C) When the curing agent contains an active ester-based curing agent, the content of the active ester-based curing agent in the resin composition is preferably 1% by mass or more, more preferably 3% by mass or more, even more preferably 5% by mass or more, and particularly preferably 7% by mass or more, when the nonvolatile components in the resin composition are considered to be 100% by mass or more. Furthermore, the content of the active ester-based curing agent in the resin composition is preferably 10% by mass or more, more preferably 30% by mass or more, even more preferably 40% by mass or more, and particularly preferably 50% by mass or more, when the curing agent (C) in the resin composition is considered to be 100% by mass or more.

[0072] (C) When the curing agent contains a phenolic curing agent, the content of the phenolic curing agent in the resin composition is preferably 0.5% by mass or more, more preferably 1% by mass or more, and particularly preferably 2% by mass or more, when the nonvolatile components in the resin composition are considered to be 100% by mass, from the viewpoint of further improving curability, and the upper limit may be 10% by mass or less, 5% by mass or less, etc.

[0073] <(D) Thermoplastic resin> The resin composition of the present invention may further contain (D) a thermoplastic resin as an optional component. The (D) thermoplastic resin is a component that does not correspond to the (B) epoxy resin described above.

[0074] (D) Examples of thermoplastic resins include polyimide resin, phenoxy resin, polyvinyl acetal resin, polyolefin resin, polybutadiene resin, polyamideimide resin, polyetherimide resin, polysulfone resin, polyethersulfone resin, polyphenylene ether resin, polycarbonate resin, polyetheretherketone resin, polyester resin, etc. (D) In ​​one embodiment, the thermoplastic resin preferably includes a thermoplastic resin selected from the group consisting of polyimide resin and phenoxy resin, and more preferably includes a phenoxy resin. Furthermore, the thermoplastic resin may be used alone or in combination of two or more types.

[0075] Specific examples of polyimide resins include "SLK-6100" manufactured by Shin-Etsu Chemical Co., Ltd., and "Ricacoat SN20" and "Ricacoat PN20" manufactured by Shin-Nippon Rika Co., Ltd.

[0076] Examples of phenoxy resins include phenoxy resins having one or more skeletons selected from the group consisting of bisphenol A skeleton, bisphenol F skeleton, bisphenol S skeleton, bisphenolacetophenone skeleton, novolac skeleton, biphenyl skeleton, fluorene skeleton, dicyclopentadiene skeleton, norbornene skeleton, naphthalene skeleton, anthracene skeleton, adamantane skeleton, terpene skeleton, and trimethylcyclohexane skeleton. The terminal end of the phenoxy resin may be any functional group such as a phenolic hydroxyl group or an epoxy group.

[0077] Specific examples of phenoxy resins include "1256" and "4250" (both phenoxy resins containing a bisphenol A skeleton) manufactured by Mitsubishi Chemical Corporation; "YX8100" (phenoxy resin containing a bisphenol S skeleton) manufactured by Mitsubishi Chemical Corporation; "YX6954" (phenoxy resin containing a bisphenol acetophenone skeleton) manufactured by Mitsubishi Chemical Corporation; "FX280" and "FX293" manufactured by Nippon Steel Chemical & Material Co., Ltd.; and "YX7200B35", "YL7500BH30", "YX6954BH30", "YX7553BH30", "YL7769BH30", "YL6794", "YL7213", "YL7290", and "YL7482" manufactured by Mitsubishi Chemical Corporation.

[0078] Examples of polyvinyl acetal resins include polyvinyl formal resin and polyvinyl butyral resin, with polyvinyl butyral resin being preferred. Specific examples of polyvinyl acetal resins include "Denka Butyral 4000-2", "Denka Butyral 5000-A", "Denka Butyral 6000-C", and "Denka Butyral 6000-EP" from Denki Kagaku Kogyo Co., Ltd.; and S-Rec BH series, BX series (e.g., BX-5Z), KS series (e.g., KS-1), BL series, and BM series from Sekisui Chemical Co., Ltd.

[0079] Examples of polyolefin resins include ethylene-based copolymer resins such as low-density polyethylene, ultra-low-density polyethylene, high-density polyethylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, and ethylene-methyl acrylate copolymer; and polyolefin polymers such as polypropylene and ethylene-propylene block copolymer.

[0080] Examples of polybutadiene resins include hydrogenated polybutadiene skeleton-containing resins, hydroxyl group-containing polybutadiene resins, phenolic hydroxyl group-containing polybutadiene resins, carboxyl group-containing polybutadiene resins, acid anhydride group-containing polybutadiene resins, epoxy group-containing polybutadiene resins, isocyanate group-containing polybutadiene resins, urethane group-containing polybutadiene resins, and polyphenylene ether-polybutadiene resins.

[0081] Specific examples of polyamide-imide resins include "Viromax HR11NN" and "Viromax HR16NN" manufactured by Toyobo Co., Ltd. Other specific examples of polyamide-imide resins include modified polyamide-imides such as "KS9100" and "KS9300" (polysiloxane skeleton-containing polyamide-imide) manufactured by Hitachi Chemical Co., Ltd.

[0082] Specific examples of polyethersulfone resins include "PES5003P" manufactured by Sumitomo Chemical Co., Ltd.

[0083] Specific examples of polysulfone resins include Solvay Advanced Polymers' polysulfones "P1700" and "P3500".

[0084] Specific examples of polyphenylene ether resins include "NORYL SA90" manufactured by SABIC. Specific examples of polyetherimide resins include "Ultem" manufactured by GE.

[0085] Examples of polycarbonate resins include hydroxyl group-containing carbonate resins, phenolic hydroxyl group-containing carbonate resins, carboxyl group-containing carbonate resins, acid anhydride group-containing carbonate resins, isocyanate group-containing carbonate resins, and urethane group-containing carbonate resins. Specific examples of polycarbonate resins include "FPC0220" from Mitsubishi Gas Chemical Co., Ltd., "T6002" and "T6001" (polycarbonate diols) from Asahi Kasei Chemicals Corporation, and "C-1090," "C-2090," and "C-3090" (polycarbonate diols) from Kuraray Co., Ltd. Specific examples of polyether ether ketone resins include "Sumiproi K" from Sumitomo Chemical Co., Ltd.

[0086] Examples of polyester resins include polyethylene terephthalate resin, polyethylene naphthalate resin, polybutylene terephthalate resin, polybutylene naphthalate resin, polytrimethylene terephthalate resin, polytrimethylene naphthalate resin, and polycyclohexanedimethyl terephthalate resin.

[0087] (D) The weight-average molecular weight (Mw) of the thermoplastic resin is preferably 5,000 or more, more preferably 8,000 or more, even more preferably 10,000 or more, particularly preferably 20,000 or more, preferably 100,000 or less, more preferably 70,000 or less, even more preferably 60,000 or less, and particularly preferably 50,000 or less, from the viewpoint of further improving film-forming properties.

[0088] The content of thermoplastic resin (D) relative to the total nonvolatile components in the resin composition is not particularly limited, but when the nonvolatile components in the resin composition are taken as 100% by mass, it is preferably 20% by mass or less, more preferably 15% by mass or less, even more preferably 10% by mass or less, even more preferably 5% by mass or less, and particularly preferably 3% by mass or less. The lower limit of the content of thermoplastic resin (D) relative to the total nonvolatile components is not particularly limited, but when the nonvolatile components in the resin composition are taken as 100% by mass, it is, for example, 0% by mass or more, 0.01% by mass or more, 0.1% by mass or more, and preferably 0.5% by mass or more, and more preferably 1% by mass or more.

[0089] <(E) Curing accelerator> The resin composition of the present invention may further contain (E) a curing accelerator as an optional component. The (E) curing accelerator functions as a curing catalyst that accelerates the curing of (B) the epoxy resin.

[0090] (E) Examples of curing accelerators include phosphorus-based curing accelerators, urea-based curing accelerators, guanidine-based curing accelerators, imidazole-based curing accelerators, metal-based curing accelerators, and amine-based curing accelerators. (E) The curing accelerator preferably contains a curing accelerator selected from imidazole-based curing accelerators and amine-based curing accelerators, and is particularly preferably a curing accelerator. (E) The curing accelerator may be used alone or in combination of two or more types.

[0091] Examples of phosphorus-based curing accelerators include aliphatic phosphonium salts such as tetrabutylphosphonium bromide, tetrabutylphosphonium chloride, tetrabutylphosphonium acetate, tetrabutylphosphonium decanoate, tetrabutylphosphonium laurate, bis(tetrabutylphosphonium) pyromelitate, tetrabutylphosphonium hydrogen hexahydrophthalate, tetrabutylphosphonium 2,6-bis[(2-hydroxy-5-methylphenyl)methyl]-4-methylphenolate, and di-tert-butylmethylphosphonium tetraphenylborate; methyltriphenylphosphonium bromide, ethyltriphenylphosphonium bromide, propyltriphenylphosphonium bromide, butyltriphenylphosphonium bromide, benzyltriphenylphosphonium chloride, tetraphenylphosphonium bromide, p-tolyltriphenylphosphonium tetra-p-tolylborate, and tetraphenylphosphonium bromide. Aromatic phosphonium salts such as tetraphenylborate, tetraphenylphosphonium tetra-p-tolylborate, triphenylethylphosphonium tetraphenylborate, tris(3-methylphenyl)ethylphosphonium tetraphenylborate, tris(2-methoxyphenyl)ethylphosphonium tetraphenylborate, (4-methylphenyl)triphenylphosphonium thiocyanate, tetraphenylphosphonium thiocyanate, and butyltriphenylphosphonium thiocyanate; aromatic phosphine-borane complexes such as triphenylphosphine-triphenylborane; aromatic phosphine-quinone addition products such as triphenylphosphine-p-benzoquinone addition products; aliphatic phosphines such as tributylphosphine, tri-tert-butylphosphine, trioctylphosphine, di-tert-butyl(2-butenyl)phosphine, di-tert-butyl(3-methyl-2-butenyl)phosphine, and tricyclohexylphosphine;Dibutylphenylphosphine, di-tert-butylphenylphosphine, methyldiphenylphosphine, ethyldiphenylphosphine, butyldiphenylphosphine, diphenylcyclohexylphosphine, triphenylphosphine, tri-o-tolylphosphine, tri-m-tolylphosphine, tri-p-tolylphosphine, tris(4-ethylphenyl)phosphine, tris(4-propylphenyl)phosphine, tris(4-isopropylphenyl)phosphine, tris(4-butylphenyl)phosphine, tris(4-tert-butylphenyl)phosphine, tris(2,4-dimethylphenyl)phosphine, tris(2,5-dimethylphenyl)phosphine, tris(2,6-dimethylphenyl)phosphine Examples include aromatic phosphines such as tris(3,5-dimethylphenyl)phosphine, tris(2,4,6-trimethylphenyl)phosphine, tris(2,6-dimethyl-4-ethoxyphenyl)phosphine, tris(2-methoxyphenyl)phosphine, tris(4-methoxyphenyl)phosphine, tris(4-ethoxyphenyl)phosphine, tris(4-tert-butoxyphenyl)phosphine, diphenyl-2-pyridylphosphine, 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane, 1,4-bis(diphenylphosphino)butane, 1,2-bis(diphenylphosphino)acetylene, and 2,2'-bis(diphenylphosphino)diphenyl ether.

[0092] Examples of urea-based curing accelerators include aliphatic dimethylureas such as 1,1-dimethylurea, 1,1,3-trimethylurea, 3-ethyl-1,1-dimethylurea, 3-cyclohexyl-1,1-dimethylurea, and 3-cyclooctyl-1,1-dimethylurea; 3-phenyl-1,1-dimethylurea, 3-(4-chlorophenyl)-1,1-dimethylurea, 3-(3,4-dichlorophenyl)-1,1-dimethylurea, 3-(3-chloro-4-methylphenyl)-1,1-dimethylurea, 3-(2-methylphenyl)-1,1-dimethylurea, 3-(4-methylphenyl)-1,1-dimethylurea, and 3-(3,4-dimethylphenyl)-1,1-dimethylurea. Aromatic dimethylureas such as toluenebisdimethylurea, 3-(4-isopropylphenyl)-1,1-dimethylurea, 3-(4-methoxyphenyl)-1,1-dimethylurea, 3-(4-nitrophenyl)-1,1-dimethylurea, 3-[4-(4-methoxyphenoxy)phenyl]-1,1-dimethylurea, 3-[4-(4-chlorophenoxy)phenyl]-1,1-dimethylurea, 3-[3-(trifluoromethyl)phenyl]-1,1-dimethylurea, N,N-(1,4-phenylene)bis(N',N'-dimethylurea), and N,N-(4-methyl-1,3-phenylene)bis(N',N'-dimethylurea) [toluenebisdimethylurea] are examples.

[0093] Examples of guanidine-based curing accelerators include dicyandiamide, 1-methylguanidine, 1-ethylguanidine, 1-cyclohexylguanidine, 1-phenylguanidine, 1-(o-tolyl)guanidine, dimethylguanidine, diphenylguanidine, trimethylguanidine, tetramethylguanidine, pentamethylguanidine, 1,5,7-triazabicyclo[4.4.0]deca-5-ene, 7-methyl-1,5,7-triazabicyclo[4.4.0]deca-5-ene, 1-methylbiguanide, 1-ethylbiguanide, 1-n-butylbiguanide, 1-n-octadecylbiguanide, 1,1-dimethylbiguanide, 1,1-diethylbiguanide, 1-cyclohexylbiguanide, 1-allylbiguanide, 1-phenylbiguanide, and 1-(o-tolyl)biguanide.

[0094] Examples of imidazole-based curing accelerators include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2- Phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6-[2'-methylimidazolyl -(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanurate adduct, 2-phenylimidazole isocyanurate adduct Examples include imidazole compounds such as 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazoline, and 2-phenylimidazoline, as well as adducts of imidazole compounds with epoxy resins.

[0095] Commercially available imidazole-based curing accelerators may be used, such as "1B2PZ," "2MZA-PW," "2PHZ-PW," and "C11Z-A" from Shikoku Chemicals, and "P200-H50" from Mitsubishi Chemical Corporation.

[0096] Examples of metal-based hardening accelerators include organometallic complexes or organometallic salts of metals such as cobalt, copper, zinc, iron, nickel, manganese, and tin. Specific examples of organometallic complexes include organocobalt complexes such as cobalt(II) acetylacetonate and cobalt(III) acetylacetonate, organocopper complexes such as copper(II) acetylacetonate, organozinc complexes such as zinc(II) acetylacetonate, organoiron complexes such as iron(III) acetylacetonate, organonickel complexes such as nickel(II) acetylacetonate, and organomanganese complexes such as manganese(II) acetylacetonate. Examples of organometallic salts include zinc octoate, tin octoate, zinc naphthenate, cobalt naphthenate, tin stearate, and zinc stearate.

[0097] Examples of amine-based curing accelerators include trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, and 1,8-diazabicyclo(5,4,0)-undecene.

[0098] As an amine-based curing accelerator, commercially available products may be used, such as "MY-25" manufactured by Ajinomoto Fine Techno Co., Ltd.

[0099] The content of (E) curing accelerator in the resin composition is not particularly limited, but when the non-volatile components in the resin composition are taken as 100% by mass, it is preferably 5% by mass or less, more preferably 1% by mass or less, even more preferably 0.5% by mass or less, and particularly preferably 0.3% by mass or less. The lower limit of the content of (E) curing accelerator in the resin composition is not particularly limited, but when the non-volatile components in the resin composition are taken as 100% by mass, it may be, for example, 0% by mass or more, 0.001% by mass or more, 0.01% by mass or more, etc.

[0100] <(F) Other additives> The resin composition of the present invention may further contain any (F) other additives as non-volatile components. Examples of such additives include: radical polymerizable compounds having vinylphenyl groups, (meth)acryloyl groups, maleimide groups, etc.; radical polymerization initiators such as peroxide-based radical polymerization initiators and azo-based radical polymerization initiators; thermosetting resins other than epoxy resins such as epoxy acrylate resins, urethane acrylate resins, urethane resins, cyanate resins, benzoxazine resins, unsaturated polyester resins, melamine resins, and silicone resins; organometallic compounds such as organocumeric compounds, organozinc compounds, and organocubalt compounds; colorants such as phthalocyanine blue, phthalocyanine green, iodine green, diazo yellow, crystal violet, titanium dioxide, and carbon black; polymerization inhibitors such as hydroquinone, catechol, pyrogallol, and phenothiazine; leveling agents such as silicone-based leveling agents and acrylic polymer-based leveling agents; thickeners such as bentonite and montmorillonite; silicone-based defoamers, acrylic-based defoamers, fluorine-based defoamers, and vinyl Antifoaming agents such as resin-based defoamers; UV absorbers such as benzotriazole-based UV absorbers; adhesion improvers such as urea silane; adhesion fertilizers such as triazole-based adhesion fertilizers, tetrazole-based adhesion fertilizers, and triazine-based adhesion fertilizers; antioxidants such as hindered phenol-based antioxidants; fluorescent whitening agents such as stilbene derivatives; surfactants such as fluorine-based surfactants and silicone-based surfactants; phosphorus-based flame retardants (e.g., phosphate ester compounds, phosphazene compounds, phosphinic acid compounds, red phosphates) Other additives include flame retardants such as nitrogen-based flame retardants (e.g., melamine sulfate), halogen-based flame retardants, and inorganic flame retardants (e.g., antimony trioxide); dispersants such as phosphate ester dispersants, polyoxyalkylene dispersants, acetylene dispersants, silicone dispersants, anionic dispersants, and cationic dispersants; and stabilizers such as borate-based stabilizers, titanate-based stabilizers, aluminate-based stabilizers, zirconate-based stabilizers, isocyanate-based stabilizers, carboxylic acid-based stabilizers, and carboxylic acid anhydride-based stabilizers. (F) Other additives may be used individually or in combination of two or more in any ratio. (F) The content of other additives can be appropriately determined by a person skilled in the art.

[0101] <(G) Organic Solvents> The resin composition of the present invention may further contain any organic solvent as a volatile component in addition to the non-volatile component described above. (G) Known organic solvents can be used as appropriate, and the type is not particularly limited. (G) Examples of organic solvents include ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; ester solvents such as methyl acetate, ethyl acetate, butyl acetate, isobutyl acetate, isoamyl acetate, methyl propionate, ethyl propionate, and γ-butyrolactone; ether solvents such as tetrahydrofuran, 1,4-dioxane, diethyl ether, diisopropyl ether, dibutyl ether, and anisole; alcohol solvents such as methanol, ethanol, propanol, butanol, and ethylene glycol; and ether solvents such as 2-ethoxyethyl acetate, propylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, ethyl diglycol acetate, γ-butyrolactone, and methyl methoxypropionate. Examples include ster-based solvents; ester alcohol-based solvents such as methyl lactate, ethyl lactate, and methyl 2-hydroxyisobutyrate; ether alcohol-based solvents such as 2-methoxypropanol, 2-methoxyethanol, 2-ethoxyethanol, propylene glycol monomethyl ether, and diethylene glycol monobutyl ether (butyl carbitol); amide-based solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methyl-2-pyrrolidone; sulfoxide-based solvents such as dimethyl sulfoxide; nitrile-based solvents such as acetonitrile and propionitrile; aliphatic hydrocarbon-based solvents such as hexane, cyclopentane, cyclohexane, and methylcyclohexane; and aromatic hydrocarbon-based solvents such as benzene, toluene, xylene, ethylbenzene, and trimethylbenzene. (G) Organic solvents may be used individually or in combination of two or more in any ratio.

[0102] The content of (G) organic solvent in the varnish-like resin composition before drying is not particularly limited, but when the total components in the resin composition are considered as 100% by mass, for example, it is preferably 40% by mass or less, more preferably 30% by mass or less, even more preferably 20% by mass or less, and particularly preferably 10% by mass or less. The content of (G) organic solvent in the resin composition that forms the resin composition layer after drying in the resin sheet is not particularly limited, but when the total components in the resin composition are considered as 100% by mass, it is preferably 5% by mass or less, more preferably 3% by mass or less, even more preferably 2% by mass or less, and particularly preferably 1% by mass or less.

[0103] <Method for producing resin compositions> The resin composition of the present invention can be produced, for example, by kneading (A) an inorganic filler, optionally (B) an epoxy resin, optionally (C) a curing agent, optionally (D) a thermoplastic resin, optionally (E) a curing accelerator, optionally (F) other additives, and optionally (G) an organic solvent, in any order and / or partially or entirely simultaneously in any preparation container. The inventors have found that the rupture of hollow inorganic filler particles, which causes a decrease in mechanical strength and is one of the problems of the present invention, occurs during the kneading of the resin composition.

[0104] One method of mixing is to use a mixing machine. Examples of mixing machines that can be used include open-type mixing machines such as two-roll or three-roll mixers, and closed-type mixing machines such as high-speed rotary mixers.

[0105] In one embodiment, when the resin composition of the present invention includes (A) an inorganic filler, (B) an epoxy resin, and (C) a curing agent, it is preferable to produce the composition by adding (A) an inorganic filler, (B) an epoxy resin, (F) other additives as needed, and (G) an organic solvent as needed, in any order and / or partially or entirely simultaneously, to any preparation container, in order to minimize the progress of undesirable reactions between (B) the epoxy resin and (C) the curing agent, and then mixing the mixture using a first kneader before adding (C) the curing agent (hereinafter referred to as "first kneading"). After mixing, it is preferable to further add (C) the curing agent, (D) a thermoplastic resin as needed, (E) a curing accelerator as needed, (F) other additives as needed, and (G) an organic solvent as needed, in any order and / or partially or entirely simultaneously, and then mixing the mixture using a second kneader (hereinafter referred to as "second kneading").

[0106] The first and second kneaders can be any of the kneaders listed above, with the first kneader preferably being an open-type kneader, more preferably a three-roll kneader, and the second kneader preferably being a closed-type kneader, more preferably a high-speed rotary mixer.

[0107] The resin composition may be degassed under low-pressure conditions, such as under vacuum, after or simultaneously with the mixing process.

[0108] <Properties of resin compositions> To date, it has been found that when conventional hollow inorganic particles (hollow inorganic fillers) with a small diameter and low average circularity, such as an average particle size of 5 μm or less, are used in resin compositions, pressure becomes localized at the convex parts of the particles during the kneading process to disperse the resin composition before curing. This causes the hollow inorganic particles to break, and the resulting fragments become the starting point for the breakage, reducing the mechanical strength of the cured product.

[0109] Furthermore, in one embodiment, as described above, first, "first mixing" is performed using an open-type kneader with very high shear stress, such as a two-roll or three-roll kneader, as the first kneader, and then "second mixing" is performed using a closed-type kneader with low shear stress, such as a high-speed rotary mixer, as the second kneader. However, in this case, it has been found that if conventional hollow inorganic particles are used, fracture is more likely to occur during "first mixing," which involves higher shear stress, compared to "second mixing."

[0110] The resin composition of the present invention is a resin composition comprising (A) an inorganic filler, wherein (A) the inorganic filler comprises (A-1) a hollow inorganic filler having an average circularity of 0.6 or more and an average particle size of 5 μm or less. As a result, the hollow inorganic filler is less likely to break during kneading, and a cured product with excellent mechanical strength and a low dielectric constant can be obtained.

[0111] The dielectric loss tangent (Df) of the cured resin composition of the present invention is 0.010 or less when measured at 5.8 GHz and 23°C as shown in Test Example 2 below, and in one embodiment, it can be preferably 0.0090 or less, more preferably 0.0085 or less, even more preferably 0.0080 or less, even more preferably 0.0075 or less, and particularly preferably 0.0070 or less.

[0112] The dielectric constant (Dk) of the cured resin composition of the present invention is 3.0 or less when measured at 5.8 GHz and 23°C as shown in Test Example 2 below, and in one embodiment, it can be preferably 2.9 or less, more preferably 2.8 or less, even more preferably 2.7 or less, particularly preferably 2.6 or less, or 2.5 or less.

[0113] The cured product of the resin composition of the present invention may have the characteristic of excellent mechanical strength. Therefore, in one embodiment, the elongation at the breaking point of the cured product measured as in Test Example 3 below may be preferably 0.5% or more, more preferably 1.0% or more, even more preferably 1.3% or more, even more preferably 1.5% or more, and particularly preferably 1.7% or more, when measured at 23°C. The upper limit of the elongation at the breaking point is not particularly limited, but can usually be 10% or less, 5% or less, etc.

[0114] In one embodiment, the cured product of the resin composition of the present invention may have the characteristic of having a low coefficient of linear thermal expansion (CTE). Therefore, in one embodiment, the coefficient of linear thermal expansion (CTE) of the cured product measured as shown in Test Example 1 below is preferably 40 ppm / °C or less, more preferably 35 ppm / °C or less, even more preferably 30 ppm / °C or less, and particularly preferably 25 ppm / °C or less. The lower limit of the coefficient of linear thermal expansion (CTE) is not particularly limited, but can be 1 ppm / °C or more.

[0115] <Uses of resin compositions> The resin composition of the present invention can be suitably used as a resin composition for insulating applications, particularly as a resin composition for forming an insulating layer. Specifically, it can be suitably used as a resin composition for forming an insulating layer (including a redistribution layer) on which a conductor layer (including a redistribution layer) is formed (a resin composition for forming an insulating layer for forming a conductor layer). Furthermore, in printed circuit boards described later, it can be suitably used as a resin composition for forming an insulating layer on a printed circuit board (a resin composition for forming an insulating layer on a printed circuit board). The resin composition of the present invention can also be used in a wide range of applications where a resin composition is required, such as sheet-like laminated materials like resin sheets and prepregs, solder resists, underfill materials, die bonding materials, semiconductor encapsulants, hole-filling resins, and component-embedding resins.

[0116] Furthermore, for example, when a semiconductor chip package is manufactured through the following steps (1) to (6), the resin composition of the present invention can be suitably used as a resin composition for a redistribution-forming layer (resin composition for forming a redistribution-forming layer) as an insulating layer for forming a redistribution layer, and as a resin composition for sealing a semiconductor chip (resin composition for sealing a semiconductor chip). When the semiconductor chip package is manufactured, a redistribution layer may be further formed on the sealing layer. (1) A step of laminating a temporary fixing film onto the substrate, (2) A step of temporarily fixing the semiconductor chip onto a temporary fixing film, (3) A step of forming a sealing layer on a semiconductor chip, (4) Steps to peel off the substrate and temporary fixing film from the semiconductor chip, (5) A step of forming a rewiring layer as an insulating layer on the surface from which the substrate and temporary fixing film of the semiconductor chip have been peeled off, and (6) Step of forming a redistribution layer as a conductor layer on the redistribution formation layer.

[0117] Furthermore, since the resin composition of the present invention provides an insulating layer with good component embedding properties, it can be suitably used even when the printed wiring board is a circuit board with embedded components.

[0118] <Sheet-like laminated material> The resin composition of the present invention can be used by applying it in a varnish state, but industrially it is generally preferable to use it in the form of a sheet-like laminate material containing the resin composition.

[0119] As sheet-like laminated materials, the following resin sheets and prepregs are preferred.

[0120] In one embodiment, the resin sheet comprises a support and a resin composition layer provided on the support, the resin composition layer being formed from the resin composition of the present invention.

[0121] The thickness of the resin composition layer is preferably 50 μm or less, more preferably 40 μm or less, from the viewpoint of thinning the printed circuit board and providing a cured product with excellent insulating properties even if the cured product of the resin composition is a thin film. The lower limit of the thickness of the resin composition layer is not particularly limited, but can usually be 5 μm or more, 10 μm or more, etc.

[0122] Examples of support materials include films made of plastic materials, metal foils, and release paper, with films made of plastic materials and metal foils being preferred.

[0123] When using a film made of plastic material as a support, examples of plastic materials include polyesters such as polyethylene terephthalate (hereinafter sometimes abbreviated as "PET") and polyethylene naphthalate (hereinafter sometimes abbreviated as "PEN"), polycarbonate (hereinafter sometimes abbreviated as "PC"), acrylics such as polymethyl methacrylate (PMMA), cyclic polyolefins, triacetylcellulose (TAC), polyether sulfide (PES), polyether ketones, and polyimides. Among these, polyethylene terephthalate and polyethylene naphthalate are preferred, and inexpensive polyethylene terephthalate is particularly preferred.

[0124] When using metal foil as a support, examples of metal foil include copper foil and aluminum foil, with copper foil being preferred. As for copper foil, foil made of single-metal copper may be used, or foil made of an alloy of copper with another metal (for example, tin, chromium, silver, magnesium, nickel, zirconium, silicon, titanium, etc.) may be used.

[0125] The support may have a matte finish, corona treatment, or antistatic treatment applied to the surface that bonds with the resin composition layer.

[0126] Furthermore, as the support, a support with a release layer may be used, which has a release layer on the surface that is bonded to the resin composition layer. Examples of release agents used in the release layer of the support with a release layer include one or more release agents selected from the group consisting of alkyd resins, polyolefin resins, urethane resins, and silicone resins. Commercially available products may be used as the support with a release layer, for example, PET films having a release layer mainly composed of an alkyd resin-based release agent, such as "SK-1", "AL-5", and "AL-7" from Lintec Corporation, "Lumirror T60" from Toray Industries, Inc., "Purex" from Teijin Corporation, and "Unipeel" from Unitika Corporation.

[0127] The thickness of the support is not particularly limited, but is preferably in the range of 5 μm to 75 μm, and more preferably in the range of 10 μm to 60 μm. When using a support with a release layer, it is preferable that the overall thickness of the support with the release layer is within the above range.

[0128] In one embodiment, the resin sheet may further include any additional layer as needed. Such an additional layer may be, for example, a protective film similar to the support, provided on the side of the resin composition layer that is not bonded to the support (i.e., the side opposite to the support). The thickness of the protective film is not particularly limited, but is, for example, 1 μm to 40 μm. By laminating the protective film, the adhesion of dust and other debris to the surface of the resin composition layer and scratches can be suppressed.

[0129] A resin sheet can be manufactured, for example, by applying a liquid resin composition onto a support using a die coater or the like, and then drying it to form a resin composition layer.

[0130] Examples of organic solvents include those similar to those described as components of the resin composition. Organic solvents may be used individually or in combination of two or more.

[0131] Drying may be carried out by known methods such as heating or blowing hot air. The drying conditions are not particularly limited, but the resin composition layer should be dried so that the content of the organic solvent in the resin composition layer is 10% by mass or less, preferably 5% by mass or less. Depending on the boiling point of the organic solvent in the resin composition or resin varnish, for example, when using a resin composition or resin varnish containing 30% to 60% by mass of organic solvent, the resin composition layer can be formed by drying at 50°C to 150°C for 3 to 10 minutes.

[0132] Resin sheets can be stored by rolling them up. If the resin sheet has a protective film, it can be used after removing the protective film.

[0133] In one embodiment, the prepreg is formed by impregnating a sheet-like fibrous substrate with the resin composition of the present invention.

[0134] The sheet-like fibrous substrate used for the prepreg is not particularly limited, and commonly used prepreg substrates such as glass cloth, aramid nonwoven fabric, and liquid crystal polymer nonwoven fabric can be used. From the viewpoint of thinning the printed circuit board, the thickness of the sheet-like fibrous substrate is preferably 50 μm or less, more preferably 40 μm or less, even more preferably 30 μm or less, and particularly preferably 20 μm or less. The lower limit of the thickness of the sheet-like fibrous substrate is not particularly limited, but is usually 10 μm or more.

[0135] Prepregs can be manufactured by known methods such as the hot melt method and the solvent method.

[0136] The thickness of the prepreg can be within the same range as the resin composition layer in the resin sheet described above.

[0137] The sheet-like laminated material of the present invention can be suitably used to form an insulating layer of a printed circuit board (for the insulating layer of a printed circuit board), and more suitably used to form an interlayer insulating layer of a printed circuit board (for the interlayer insulating layer of a printed circuit board).

[0138] <Printed wiring board> The printed circuit board of the present invention includes an insulating layer made of a cured product obtained by curing the resin composition of the present invention.

[0139] Printed circuit boards can be manufactured, for example, using the resin sheet described above, by a method including the following steps (I) and (II). (I) A process of laminating a resin sheet onto an inner layer substrate such that the resin composition layer of the resin sheet is bonded to the inner layer substrate. (II) A step of curing (e.g., thermal curing) the resin composition layer to form an insulating layer.

[0140] The "internal layer substrate" used in process (I) is a material that serves as the substrate for a printed wiring board, and examples include glass epoxy substrates, metal substrates, polyester substrates, polyimide substrates, BT resin substrates, thermosetting polyphenylene ether substrates, etc. The substrate may also have a conductive layer on one or both sides, and this conductive layer may be patterned. An internal layer substrate in which a conductive layer (circuit) is formed on one or both sides of the substrate is sometimes called an "internal layer circuit board." Furthermore, an intermediate product on which an insulating layer and / or a conductive layer is to be formed during the manufacturing of a printed wiring board is also included in the "internal layer substrate" as defined in this invention. If the printed wiring board is a circuit board with embedded components, an internal layer substrate with embedded components may be used.

[0141] Lamination of the inner layer substrate and the resin sheet can be performed, for example, by heating and pressing the resin sheet onto the inner layer substrate from the support side. Examples of the member used to heat and press the resin sheet onto the inner layer substrate (hereinafter also referred to as the "heat-pressing member") include a heated metal plate (such as a SUS end plate) or a metal roll (such as a SUS roll). It is preferable to press the resin sheet via an elastic material such as heat-resistant rubber, rather than directly pressing the heat-pressing member onto the resin sheet, so that the resin sheet can adequately follow the surface irregularities of the inner layer substrate.

[0142] Lamination of the inner layer substrate and the resin sheet may be carried out by a vacuum lamination method. In the vacuum lamination method, the heat-pressure temperature is preferably in the range of 60°C to 160°C, more preferably in the range of 80°C to 140°C, the heat-pressure pressure is preferably in the range of 0.098 MPa to 1.77 MPa, more preferably in the range of 0.29 MPa to 1.47 MPa, and the heat-pressure time is preferably in the range of 20 seconds to 400 seconds, more preferably in the range of 30 seconds to 300 seconds. Lamination may preferably be carried out under reduced pressure conditions of 26.7 hPa or less.

[0143] Lamination can be performed using a commercially available vacuum laminator. Examples of commercially available vacuum laminators include vacuum pressure laminators manufactured by Meiki Seisakusho Co., Ltd., vacuum applicators manufactured by Nikko Materials Co., Ltd., and batch-type vacuum pressure laminators.

[0144] After lamination, the laminated resin sheets may be smoothed by pressing a heat-sealing member from the support side under normal pressure (atmospheric pressure). The pressing conditions for the smoothing process can be the same as the heat-sealing conditions for lamination. The smoothing process can be performed using a commercially available laminator. Lamination and smoothing may be performed continuously using the commercially available vacuum laminator mentioned above.

[0145] The support may be removed between steps (I) and (II), or after step (II).

[0146] In step (II), the resin composition layer is cured (e.g., by thermal curing) to form an insulating layer made of the cured resin composition. The curing conditions for the resin composition layer are not particularly limited, and conditions commonly used when forming an insulating layer for a printed circuit board may be used.

[0147] For example, the thermal curing conditions for the resin composition layer vary depending on the type of resin composition, but in one embodiment, the curing temperature is preferably 120°C to 240°C, more preferably 150°C to 220°C, and even more preferably 170°C to 210°C. The curing time can be preferably 5 minutes to 120 minutes, more preferably 10 minutes to 100 minutes, and even more preferably 15 minutes to 100 minutes.

[0148] Prior to thermal curing the resin composition layer, the resin composition layer may be preheated at a temperature lower than the curing temperature. For example, prior to thermal curing the resin composition layer, it may be preheated at a temperature of 50°C to 120°C, preferably 60°C to 115°C, more preferably 70°C to 110°C for 5 minutes or more, preferably 5 minutes to 150 minutes, more preferably 15 minutes to 120 minutes, and even more preferably 15 minutes to 100 minutes.

[0149] In manufacturing printed circuit boards, the following steps may be further performed: (III) drilling holes in the insulating layer, (IV) roughening the insulating layer, and (V) forming the conductor layer. These steps (III) through (V) may be carried out according to various methods known to those skilled in the art that are used in the manufacture of printed circuit boards. If the support is removed after step (II), the removal of the support may be carried out between steps (II) and (III), between steps (III) and (IV), or between steps (IV) and (V). Furthermore, if necessary, the formation of the insulating layer and the conductor layer in steps (II) through (V) may be repeated to form a multilayer circuit board.

[0150] In other embodiments, the printed circuit board of the present invention can be manufactured using the prepreg described above. The manufacturing method is basically the same as when a resin sheet is used.

[0151] Step (III) is a step of drilling holes in the insulating layer, thereby forming holes such as via holes and through holes in the insulating layer. Step (III) may be carried out using, for example, a drill, laser, plasma, etc., depending on the composition of the resin composition used to form the insulating layer. The dimensions and shape of the holes may be appropriately determined according to the design of the printed circuit board.

[0152] Step (IV) is a process for roughening the insulating layer. Typically, smear removal is also performed in this step (IV). The procedure and conditions for the roughening process are not particularly limited, and known procedures and conditions commonly used when forming the insulating layer of a printed circuit board can be adopted. For example, the insulating layer can be roughened by performing swelling treatment with a swelling solution, roughening treatment with an oxidizing agent, and neutralization treatment with a neutralizing solution in this order.

[0153] The swelling solution used for the roughening treatment is not particularly limited, but examples include alkaline solutions and surfactant solutions, and is preferably an alkaline solution, with sodium hydroxide solution and potassium hydroxide solution being more preferred. Examples of commercially available swelling solutions include "Swelling Dip Securing P" and "Swelling Dip Securing SBU" manufactured by Atotec Japan. The swelling treatment with the swelling solution is not particularly limited, but can be carried out, for example, by immersing the insulating layer in a swelling solution at 30°C to 90°C for 1 to 20 minutes. From the viewpoint of suppressing the swelling of the resin of the insulating layer to an appropriate level, it is preferable to immerse the insulating layer in a swelling solution at 40°C to 80°C for 5 to 15 minutes.

[0154] The oxidizing agent used for the roughening treatment is not particularly limited, but examples include an alkaline permanganate solution obtained by dissolving potassium permanganate or sodium permanganate in an aqueous solution of sodium hydroxide. The roughening treatment with an oxidizing agent such as an alkaline permanganate solution is preferably carried out by immersing the insulating layer in an oxidizing agent solution heated to 60°C to 100°C for 10 to 30 minutes. Furthermore, the concentration of permanganate in the alkaline permanganate solution is preferably 5% to 10% by mass. Examples of commercially available oxidizing agents include alkaline permanganate solutions such as "Concentrate Compact CP" and "Dosing Solution Securigans P" manufactured by Attec Japan.

[0155] Furthermore, an acidic aqueous solution is preferred as the neutralizing solution used in the roughening treatment. A commercially available example is "Reduction Solution Securigant P" manufactured by Attec Japan.

[0156] The neutralization treatment can be carried out by immersing the treated surface, which has been roughened with an oxidizing agent, in a neutralization solution at 30°C to 80°C for 5 to 30 minutes. From the standpoint of workability, it is preferable to immerse the object, which has been roughened with an oxidizing agent, in a neutralization solution at 40°C to 70°C for 5 to 20 minutes.

[0157] In one embodiment, the arithmetic mean roughness (Ra) of the insulating layer surface after roughening treatment is not particularly limited, but is preferably 500 nm or less, more preferably 400 nm or less, and even more preferably 300 nm or less. The lower limit is not particularly limited and can be, for example, 1 nm or more, 2 nm or more, etc. Also, the root mean square roughness (Rq) of the insulating layer surface after roughening treatment is preferably 500 nm or less, more preferably 400 nm or less, and even more preferably 300 nm or less. The lower limit is not particularly limited and can be, for example, 1 nm or more, 2 nm or more, etc. The arithmetic mean roughness (Ra) and root mean square roughness (Rq) of the insulating layer surface can be measured using a non-contact surface roughness meter.

[0158] Step (V) is a step of forming a conductive layer, in which a conductive layer is formed on an insulating layer. The conductive material used for the conductive layer is not particularly limited. In a preferred embodiment, the conductive layer contains one or more metals selected from the group consisting of gold, platinum, palladium, silver, copper, aluminum, cobalt, chromium, zinc, nickel, titanium, tungsten, iron, tin, and indium. The conductive layer may be a single-metal layer or an alloy layer, and examples of alloy layers include layers formed from alloys of two or more metals selected from the above group (e.g., nickel-chromium alloy, copper-nickel alloy, and copper-titanium alloy). In particular, from the viewpoint of versatility in conductor layer formation, cost, and ease of patterning, single metal layers of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver, or copper, or alloy layers of nickel-chromium alloy, copper-nickel alloy, or copper-titanium alloy are preferred, single metal layers of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver, or copper, or alloy layers of nickel-chromium alloy are more preferred, and single metal layers of copper are even more preferred.

[0159] The conductive layer may be a single-layer structure, or it may be a multi-layer structure in which two or more single-metal layers or alloy layers made of different types of metals or alloys are laminated. When the conductive layer is a multi-layer structure, the layer in contact with the insulating layer is preferably a single-metal layer of chromium, zinc, or titanium, or an alloy layer of nickel-chromium alloy.

[0160] The thickness of the conductor layer depends on the desired printed circuit board design, but is generally 3 μm to 35 μm, preferably 5 μm to 30 μm.

[0161] In one embodiment, the conductor layer may be formed by plating. For example, a conductor layer having a desired wiring pattern can be formed by plating the surface of the insulating layer using conventionally known techniques such as the semi-additive method or the fully additive method. From the viewpoint of ease of manufacture, it is preferable to form it by the semi-additive method. An example of forming the conductor layer by the semi-additive method is shown below.

[0162] First, a plating seed layer is formed on the surface of the insulating layer by electroless plating. Next, a mask pattern is formed on the formed plating seed layer, exposing a portion of the plating seed layer corresponding to the desired wiring pattern. After forming a metal layer on the exposed plating seed layer by electroplating, the mask pattern is removed. Then, the unnecessary plating seed layer can be removed by etching or other means to form a conductor layer having the desired wiring pattern.

[0163] In other embodiments, the conductor layer may be formed using metal foil. When forming the conductor layer using metal foil, step (V) is preferably performed between steps (I) and (II). For example, after step (I), the support is removed and the metal foil is laminated onto the surface of the exposed resin composition layer. The lamination of the resin composition layer and the metal foil may be carried out by a vacuum lamination method. The lamination conditions may be the same as those described for step (I). Next, step (II) is performed to form an insulating layer. Subsequently, the metal foil on the insulating layer can be used to form a conductor layer having a desired wiring pattern by conventional known techniques such as the subtractive method or the modified semi-additive method.

[0164] Metal foils can be manufactured by known methods such as electrolysis and rolling. Examples of commercially available metal foils include HLP foil and JXUT-III foil manufactured by JX Nippon Oil & Metals Corporation, and 3EC-III foil and TP-III foil manufactured by Mitsui Mining & Smelting Co., Ltd.

[0165] <Semiconductor device> The semiconductor device of the present invention includes the printed circuit board of the present invention. The semiconductor device of the present invention can be manufactured using the printed circuit board of the present invention.

[0166] Examples of semiconductor devices include various types of semiconductor devices used in electrical products (e.g., computers, mobile phones, digital cameras, and televisions) and vehicles (e.g., motorcycles, automobiles, trains, ships, and aircraft). [Examples]

[0167] The present invention will be described in detail below with reference to examples. The present invention is not limited to these examples. In the following, unless otherwise specified, "parts" and "%" refer to "parts by mass" and "mass%", respectively. Unless otherwise specified, the temperature conditions in the following description shall be room temperature (25°C), and unless the pressure conditions are specified, the pressure conditions shall be normal pressure (1 atm).

[0168] <Example 1> Thirty parts of bisphenol A type epoxy resin (Mitsubishi Chemical Corporation's "828US," epoxy equivalent approximately 180 g / eq.) and thirty parts of biphenyl type epoxy resin (Nippon Kayaku Co., Ltd.'s "NC3000H," epoxy equivalent approximately 269 g / eq.) were heated and dissolved in 55 parts of solvent naphtha with stirring, and then cooled to room temperature. To this mixed solution, 144 parts of hollow silica particles 1 (average particle size 2.0 μm, average circularity 0.7, porosity 20 vol%) surface-treated with an aminosilane coupling agent (Shin-Etsu Chemical Co., Ltd.'s "KBM573") and 80 parts of non-hollow silica particles (Admatex Corporation's "SO-C2," average particle size 0.5 μm, average circularity 0.9) surface-treated with an aminosilane coupling agent (Shin-Etsu Chemical Co., Ltd.'s "KBM573") were added, and the mixture was kneaded with a three-roller to uniformly disperse the particles. To the roll dispersion, 14 parts of a triazine skeleton-containing phenolic curing agent (DIC Corporation's "LA-3018-50P", hydroxyl group equivalent approximately 151, 50% solids solution of 2-methoxypropanol), 40 parts of a dicyclopentadiene-type active ester compound (DIC Corporation's "HPC-8000-65T", active group equivalent approximately 223, 65% by mass toluene solution of non-volatile components), 20 parts of a phenoxy resin (Mitsubishi Chemical Corporation's "YX6954BH30", 30% solids solution of MEK and cyclohexanone in a 1:1 mixture), and 6 parts of a curing accelerator ("DMAP", 4-dimethylaminopyridine, 5% by mass MEK solution) were mixed and uniformly dispersed in a high-speed rotary mixer to prepare a varnish-like resin composition.

[0169] <Example 2> A varnish-like resin composition was prepared in the same manner as in Example 1, except that the amount of surface-treated hollow silica particles 1 (average particle size 2.0 μm, average circularity 0.7, porosity 20 vol%) used was changed from 144 parts to 208 parts, and 80 parts of surface-treated non-hollow silica particles (Admatex "SO-C2", average particle size 0.5 μm, average circularity 0.9) were not used.

[0170] <Example 3> A varnish-like resin composition was prepared in the same manner as in Example 1, except that 36 parts of hollow aluminosilicate particles ("MG-005" manufactured by Taiheiyo Cement Corporation, average particle size 1.6 μm, porosity 80 vol%) were used instead of 144 parts of surface-treated hollow silica particles 1 (average particle size 2.0 μm, average circularity 0.7, porosity 20 vol%).

[0171] <Example 4> A varnish-like resin composition was prepared in the same manner as in Example 1, except that 30 parts of naphthol-type epoxy resin (ESN475V, manufactured by Nippon Steel Chemical & Material Co., Ltd., epoxy equivalent 332 g / eq.) were used instead of 30 parts of biphenyl-type epoxy resin (NC3000H, manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent approx. 269 g / eq.).

[0172] <Example 5> A varnish-like resin composition was prepared in the same manner as in Example 1, except that 30 parts of bixylenol-type epoxy resin (Mitsubishi Chemical Industries, Ltd., "YX4000HK", epoxy equivalent approximately 185 g / eq.) were used instead of 30 parts of biphenyl-type epoxy resin (Nippon Kayaku Co., Ltd., "NC3000H", epoxy equivalent approximately 269 g / eq.) as in Example 1.

[0173] <Example 6> A varnish-like resin composition was prepared in the same manner as in Example 1, except that 42 parts of a naphthalene-type active ester compound (DIC Corporation's "HPC-8150-62T", a toluene solution containing approximately 229 active groups and 62% by mass of non-volatile components) were used instead of 40 parts of the dicyclopentadiene-type active ester compound (DIC Corporation's "HPC-8000-65T", a toluene solution containing approximately 223 equivalent active groups and 65% by mass of non-volatile components) used in Example 1.

[0174] <Example 7> A varnish-like resin composition was prepared in the same manner as in Example 1, except that the amount of dicyclopentadiene-type active ester compound (DIC Corporation's "HPC-8000-65T", active group equivalent of approximately 223, toluene solution with 65% by mass of non-volatile components) used was changed from 40 parts to 20 parts, and 21 parts of naphthalene-type active ester compound (DIC Corporation's "HPC-8150-62T", active group equivalent of approximately 229, toluene solution with 62% by mass of non-volatile components) were used.

[0175] <Comparative Example 1> A varnish-like resin composition was prepared in the same manner as in Example 1, except that 144 parts of surface-treated hollow silica particles 1 (average particle size 2.0 μm, average circularity 0.7, porosity 20 vol%) were not used, and the amount of surface-treated non-hollow silica particles (Admatex "SO-C2", average particle size 0.5 μm, average circularity 0.9) used was changed from 80 parts to 260 parts.

[0176] <Comparative Example 2> A varnish-like resin composition was prepared in the same manner as in Example 1, except that 144 parts of surface-treated hollow silica particles 1 (average particle size 2.0 μm, average circularity 0.7, porosity 20 vol%) were not used, and instead of 80 parts of surface-treated non-hollow silica particles (SO-C2, manufactured by Admatex, average particle size 0.5 μm, average circularity 0.9), 260 parts of non-hollow silica particles (IMSIL A-8, manufactured by Unimin, manufactured by Shin-Etsu Chemical Co., Ltd., average particle size 2.2 μm, average circularity 0.5) surface-treated with an aminosilane coupling agent (KBM573, manufactured by Shin-Etsu Chemical Co., Ltd.) were used.

[0177] <Comparative Example 3> A varnish-like resin composition was prepared in the same manner as in Example 1, except that 135 parts of hollow silica particles 2 (average particle size 2.6 μm, average circularity 0.5, porosity 25% by volume), which were surface-treated with an aminosilane coupling agent ("KBM573" manufactured by Shin-Etsu Chemical Co., Ltd.), were used instead of 144 parts of surface-treated hollow silica particles 1 (average particle size 2.0 μm, average circularity 0.7, porosity 20% by volume).

[0178] <Test Example A: Measurement of the average particle size of inorganic filler particles> 100 mg of inorganic filler particles and 10 g of methyl ethyl ketone used in each example and comparative example were weighed into vials and dispersed using ultrasound for 10 minutes. Using a laser diffraction particle size distribution analyzer (Horiba LA-960), with blue and red light source wavelengths, the particle size distribution of the inorganic particles was measured on a volume basis using a flow cell method. From the obtained particle size distribution, the average particle size of the inorganic particles was calculated as the median diameter.

[0179] <Test Example B: Calculation of porosity of inorganic filler particles> The density of the inorganic filler particles used in each example and comparative example was measured using a true density analyzer (QUANTACHROME "ULTRAPYCNOMETER1000"). Nitrogen was used as the measuring gas in this measurement. Subsequently, the measured density D of the inorganic filler was measured. M And the theoretical value D of the material density of the material forming the inorganic filler particles. T The porosity P of the inorganic filler particles was calculated by substituting this into equation (2) described above. Note that the theoretical value D of silica is also used. T This is 2.2 g / cm³ 3 That's what I decided.

[0180] <Test Example C: Calculation of the average circularity of inorganic filler particles> The inorganic filler particles used in each example and comparative example were image-analyzed using a particle shape image analyzer (PITA-04, manufactured by Seishin Corporation). Silica particles dispersed in the dilution solvent methyl ethyl ketone (hereinafter abbreviated as "MEK") were injected into the analyzer, and data on the projected area S and perimeter L of the particles in the image were collected for more than 1000 particles in each sample using a 20x optical lens. These values ​​were substituted into equation (1) described above to calculate the circularity φ, and the average circularity was calculated from the calculated circularity.

[0181] <Test Example 1: Measurement of the linear thermal expansion coefficient of a cured product> A PET film with an alkyd resin release layer (Lintec Corporation's "AL5", 38 μm thick) was prepared as a support. The varnish-like resin compositions prepared in the examples and comparative examples were uniformly applied to the release layer of the support so that the thickness of the dried resin composition layer was 40 μm, and a resin sheet was prepared by drying at 80-120°C (average 100°C) for 5 minutes.

[0182] A resin sheet with a resin composition layer thickness of 40 μm was heated at 200°C for 90 minutes to thermocure the resin composition layer. After that, the support was peeled off to obtain a cured product for evaluation. The cured product for evaluation was cut into test pieces with a width of 5 mm and a length of 15 mm. Thermomechanical analysis was performed on these test pieces using a thermomechanical analyzer (Rigaku Corporation's "Thermo Plus TMA8310") by the tensile loading method. Specifically, after mounting the test piece in the thermomechanical analyzer, measurements were taken twice consecutively under measurement conditions of a load of 1 g and a heating rate of 5°C / min. The linear thermal expansion coefficient (ppm / °C) in the planar direction in the range of 25°C to 150°C was calculated for both measurements.

[0183] <Test Example 2: Measurement of relative permittivity and dielectric loss tangent of cured material> The cured material for evaluation, obtained using the same method as in Test Example 1, was cut into test specimens measuring 2 mm in width and 80 mm in length. The relative permittivity and dielectric loss tangent of these test specimens were measured using the cavity resonance perturbation method with an Agilent Technologies HP8362B at a measurement frequency of 5.8 GHz and a measurement temperature of 23°C. Measurements were performed on two test specimens, and the average values ​​were calculated.

[0184] <Test Example 3: Measurement of Elongation at Breaking Point of Hardened Material> The evaluation cured material obtained using the same method as in Test Example 1 was subjected to a tensile test using a Tensilon universal testing machine (RTC-1250A, manufactured by Orientec Co., Ltd.) in accordance with the Japanese Industrial Standard (JIS K7127), and the elongation at the breaking point (%) was measured.

[0185] The non-volatile component content of the resin compositions in the examples and comparative examples, the calculation results of the test examples, and the measurement results are shown in Table 1 below.

[0186] [Table 1]

[0187] As shown in Table 1, by using a resin composition that includes (A) an inorganic filler, wherein (A) the inorganic filler is (A-1) a hollow inorganic filler with an average circularity of 0.6 or more and an average particle size of 5 μm or less, it is possible to obtain a cured product with excellent mechanical strength and a low dielectric constant.

Claims

1. A resin composition comprising (A) silica, (B) epoxy resin, and (C) curing agent, (A) Component comprises (A-1) hollow silica having an average circularity of 0.6 or more and an average particle size of 5 μm or less, and (A-2) non-hollow silica. (A) The content of component is 60% by mass or more, when the nonvolatile components in the resin composition are taken as 100% by mass. (A-1) The content of component is 30% by mass or more, when the nonvolatile components in the resin composition are taken as 100% by mass. When the total amount of component (A) in the resin composition is considered to be 100% by mass, the content of component (A-1) is 30 to 80% by mass, and the content of component (A-2) is 20 to 70% by mass. (C) Component contains an active ester-based curing agent, The dielectric loss tangent (Df) of the cured resin composition is 0.010 or less when measured at 5.8 GHz and 23°C, and A resin composition in which the relative permittivity (Dk) of the cured product is 3.0 or less when measured at 5.8 GHz and 23°C.

2. The resin composition according to claim 1, wherein the average circularity of component (A-1) is 0.6 or more and 0.7 or less.

3. The resin composition according to claim 1, wherein the average particle size of component (A-1) is 0.3 μm or more.

4. The resin composition according to claim 1, wherein the porosity of component (A-1) is 15% by volume or more.

5. The resin composition according to claim 1, wherein the content of the active ester-based curing agent is 1% by mass or more, when the non-volatile components in the resin composition are considered to be 100% by mass.

6. The resin composition according to claim 1, wherein component (C) contains a naphthalene-type active ester curing agent.

7. The resin composition according to claim 1, wherein component (C) contains a phenolic curing agent.

8. (D) The resin composition according to claim 1, further comprising a thermoplastic resin.

9. The resin composition according to claim 8, wherein component (D) comprises a phenoxy resin.

10. The resin composition according to claim 1, wherein the elongation at the breaking point of the cured resin composition is 1.0% or more when measured at 23°C.

11. The resin composition according to claim 1, wherein the linear thermal expansion coefficient of the cured product of the resin composition is 30 ppm / °C or less.

12. A cured product of the resin composition according to any one of claims 1 to 11.

13. A sheet-like laminated material containing the resin composition according to any one of claims 1 to 11.

14. A resin sheet having a support and a resin composition layer formed from the resin composition according to any one of claims 1 to 11, provided on the support.

15. A printed circuit board comprising an insulating layer made of a cured product of the resin composition according to any one of claims 1 to 11.

16. A semiconductor device comprising a printed circuit board as described in claim 15.

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