Resin composition

Abstract

To provide a resin composition which can obtain a cured product which can reduce tackiness even when an inorganic filler is blended in a small amount and has excellent flexibility and excellent insulation reliability.SOLUTION: The resin composition contains (A) an epoxy resin, (B) an inorganic filler and (C) a polyimide resin, in which the component (A) contains (A-1) a siloxane skeleton-containing epoxy resin, and a content of the component (B) is 40 mass% or less when a non-volatile component in the resin composition is 100 mass%.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a resin composition containing a polyimide resin. Furthermore, it relates to a cured product, a resin sheet, a multilayer flexible substrate, and a semiconductor device obtained using the resin composition. [Background technology]

[0002] In recent years, there has been a growing demand for thinner, lighter, and more densely mounted semiconductor components. To meet this demand, flexible substrates are attracting attention as substrates for semiconductor components. Flexible substrates can be made thinner and lighter than rigid substrates. Furthermore, because flexible substrates are flexible and deformable, they can be bent and mounted.

[0003] In general, flexible substrates require the incorporation of flexible resins such as polyimide resins as insulating materials. However, the incorporation of polyimide resins can increase tackiness (adhesion), making them difficult to handle. While it is possible to suppress tackiness by incorporating inorganic fillers (Patent Document 1), it becomes difficult to achieve flexibility at the same time as the proportion of inorganic fillers increases. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2014-95047 [Overview of the project] [Problems that the invention aims to solve]

[0005] The object of the present invention is to provide a resin composition, etc., that can produce a cured product with low tackiness despite a low concentration of inorganic fillers, and which also possesses excellent flexibility and excellent insulation reliability. [Means for solving the problem]

[0006] In order to achieve the object of the present invention, as a result of intensive studies by the present inventors, a resin composition containing (A) an epoxy resin, (B) an inorganic filler, and (C) a polyimide resin, wherein the component (A) is a resin composition containing (A-1) a siloxane skeleton-containing epoxy resin is used, so that even when the content of the (B) inorganic filler is as low as 40% by mass or less, the tackiness can be suppressed low, and a cured product having excellent flexibility and excellent insulation reliability can be obtained. The present invention has been completed based on this finding.

[0007] That is, the present invention includes the following contents. [1] A resin composition containing (A) an epoxy resin, (B) an inorganic filler, and (C) a polyimide resin, where the component (A) contains (A-1) a siloxane skeleton-containing epoxy resin, and the content of the component (B) is 40% by mass or less when the non-volatile components in the resin composition are 100% by mass. [2] The resin composition according to [1] above, wherein the component (A-1) is a cyclic siloxane skeleton-containing epoxy resin. [3] The component (A-1) has the formula (A1):

[0008] [Chemical formula]

[0009] [In the formula, R 1 each independently represents an epoxyalkyl group; R 2 each independently represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, or a substituted or unsubstituted aryl group; R 3 and R 4 each independently represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, or a substituted or unsubstituted aryl group, or R 3 and R 4The resin composition according to [1] or [2] above, wherein the compounds are combined to form a single -O- and bonded to each other, forming a cyclic siloxane skeleton; s is an integer of 1 or more. [4] The resin composition according to any one of [1] to [3] above, wherein the molecular weight of component (A-1) is 800 or less. [5] The resin composition according to any of [1] to [4] above, wherein the epoxy equivalent of component (A-1) is 150 g / eq. to 250 g / eq. [6] The resin composition according to any one of [1] to [5] above, wherein the content of component (A-1) is 5% by mass or more when the nonvolatile components in the resin composition are taken as 100% by mass. [7] The resin composition according to any one of [1] to [6] above, wherein the content of component (A-1) is 10% by mass or less when the nonvolatile components in the resin composition are taken as 100% by mass. [8] The resin composition according to any one of [1] to [7] above, wherein the average particle size of component (B) is 1 μm or less. [9] The resin composition according to any one of [1] to [8] above, wherein component (B) is silica.

[10] The resin composition according to any one of [1] to [9] above, wherein the weight-average molecular weight of component (C) is 1,000 or more and 100,000 or less.

[11] The resin composition according to any one of [1] to

[10] above, wherein the content of component (C) is 20% by mass or more when the nonvolatile components in the resin composition are taken as 100% by mass.

[12] The resin composition according to any one of [1] to

[11] above, wherein the content of component (C) is 30% by mass or less when the nonvolatile components in the resin composition are taken as 100% by mass.

[13] The resin composition according to any of [1] to

[12] above, further comprising (D) a curing agent.

[14] The resin composition according to

[13] above, wherein component (D) contains an active ester curing agent.

[15] A resin composition according to any one of [1] to

[14] above, for forming an insulating layer on a multilayer flexible substrate.

[16] A cured product of any of the resin compositions described in [1] to

[15] above.

[17] A resin sheet comprising a support and a resin composition layer formed of any of the resin compositions described in [1] to

[15] above, provided on the support.

[18] A multilayer flexible substrate comprising an insulating layer formed by curing any of the resin compositions described in [1] to

[15] above.

[19] A semiconductor device comprising the multilayer flexible substrate described in

[18] above. [Effects of the Invention]

[0010] According to the resin composition of the present invention, it is possible to obtain a cured product that has low tackiness despite a low concentration of inorganic fillers, as well as excellent flexibility and excellent insulation reliability. [Modes for carrying out the invention]

[0011] 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.

[0012] <Resin composition> The present invention provides a resin composition comprising (A) an epoxy resin, (B) an inorganic filler, and (C) a polyimide resin, wherein component (A) contains (A-1) a siloxane skeleton-containing epoxy resin, and the content of component (B) is 40% by mass or less. By using such a resin composition, it is possible to obtain a cured product that has low tackiness despite a low concentration of inorganic filler, as well as excellent flexibility and excellent insulation reliability.

[0013] The resin composition of the present invention may further contain any optional components in addition to (A) epoxy resin, (B) inorganic filler, and (C) polyimide resin. Examples of optional components include (D) curing agent, (E) curing accelerator, (F) other additives, and (G) organic solvent. The components contained in the resin composition will be described in detail below.

[0014] <(A) Epoxy resin> The resin composition of the present invention comprises (A) an epoxy resin. (A) refers to a curable resin having epoxy groups. (A) also includes modified epoxy resins.

[0015] The content of epoxy resin (A) in the resin composition is not particularly limited, but when the non-volatile components in the resin composition are considered to be 100% by mass, it is preferably 10% by mass or more, more preferably 20% by mass or more, even more preferably 25% by mass or more, and particularly preferably 30% by mass or more. The upper limit of the content of epoxy resin (A) in the resin composition is not particularly limited, but when the non-volatile components in the resin composition are considered to be 100% by mass, it is preferably 70% by mass or less, more preferably 60% by mass or less, even more preferably 50% by mass or less, and particularly preferably 40% by mass or less.

[0016] <(A-1) Siloxane skeleton-containing epoxy resin> (A) Epoxy resins include (A-1) siloxane skeleton-containing epoxy resins. (A-1) Siloxane skeleton-containing epoxy resins refer to compounds having two or more epoxy groups and siloxane (Si-O-Si) bonds.

[0017] (A-1) The siloxane skeleton-containing epoxy resin may be a cyclic siloxane skeleton-containing epoxy resin or a linear siloxane skeleton-containing epoxy resin, but a cyclic siloxane skeleton-containing epoxy resin is preferred.

[0018] (A-1) The number of silicon atoms forming siloxane bonds in a siloxane skeleton-containing epoxy resin is not particularly limited, but is preferably 3 or more per molecule, preferably 10 or less, more preferably 8 or less, even more preferably 6 or less, and even more preferably 5 or less. Particularly preferably is 4.

[0019] (A-1) The number of epoxy groups in the epoxy resin containing a siloxane skeleton is not particularly limited, but in one molecule, it can preferably be 3 or more, preferably 10 or less, more preferably 8 or less, still more preferably 6 or less, and even more preferably 5 or less. Particularly preferably, it is 4.

[0020] (A-1) In the epoxy resin containing a siloxane skeleton, it is preferable that all substitutable sites of the silicon atom are substituted with a hydrocarbon group such as an alkyl group, an alkenyl group, or an aryl group having or not having an epoxy group. The hydrocarbon group may have a substituent other than the epoxy group.

[0021] (A-1) The epoxy resin containing a siloxane skeleton is preferably of the formula (A1):

[0022] [Chemical formula]

[0023] [In the formula, R 1 each independently represents an epoxyalkyl group; R 2 each independently represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, or a substituted or unsubstituted aryl group; R 3 and R 4 each independently represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, or a substituted or unsubstituted aryl group, or R 3 and R 4 together represent one -O- and are bonded to each other to form a cyclic siloxane skeleton; s represents an integer of 1 or more. ] It is a compound represented by.

[0024] "Alkyl(group)" refers to a linear, branched, and / or cyclic monovalent aliphatic saturated hydrocarbon group. The alkyl(group) is preferably an alkyl group having 1 to 10 carbon atoms. Examples of alkyl(groups) include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl, sec-pentyl, tert-pentyl, cyclopentyl, cyclohexyl, cyclopentylmethyl, 2-cyclohexylmethyl, 2-cyclopentylethyl, and 2-cyclohexylethyl groups.

[0025] An "epoxyalkyl group" is a group in which two hydrogen atoms bonded to different carbon atoms of an alkyl group are replaced by one oxygen atom, forming an oxacyclopropane (ethylene oxide) ring. Epoxyalkyl groups with 2 to 10 carbon atoms are preferred. Examples of epoxyalkyl groups include: linear epoxyalkyl groups such as 2,3-epoxypropyl, 3,4-epoxybutyl, 4,5-epoxypentyl, and 5,6-epoxyhexyl; branched epoxyalkyl groups such as 2,3-epoxy-2-methylpropyl and 3,4-epoxy-3-methylbutyl; cyclic epoxyalkyl groups such as 2,3-epoxycyclopentyl, 3,4-epoxycyclopentyl, 2,3-epoxycyclohexyl, and 3,4-epoxycyclohexyl; 2,3-epoxycyclopentylmethyl, 3,4-epoxycyclopentylmethyl, 2,3-epoxycyclohexylmethyl, and 2-(2,3-epoxy) Examples include linear alkyl groups having cyclic epoxyalkyl groups at their termini, such as cyclopentyl)ethyl group, 2-(3,4-epoxycyclopentyl)ethyl group, 2-(2,3-epoxycyclohexyl)ethyl group, 2-(3,4-epoxycyclohexyl)ethyl group, 3-(2,3-epoxycyclopentyl)propyl group, 3-(3,4-epoxycyclopentyl)propyl group, 3-(2,3-epoxycyclohexyl)propyl group, 3-(3,4-epoxycyclohexyl)propyl group, 4-(2,3-epoxycyclopentyl)butyl group, 4-(3,4-epoxycyclopentyl)butyl group, and 4-(3,4-epoxycyclohexyl)butyl group.

[0026] An "alkenyl group" refers to a linear, branched, and / or cyclic monovalent aliphatic unsaturated hydrocarbon group having at least one carbon-carbon double bond. Preferably, the alkenyl group has 2 to 10 carbon atoms. Examples of alkenyl groups include vinyl, 1-propenyl, 2-propenyl, 2-methyl-1-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 3-methyl-2-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 4-methyl-3-pentenyl, 1-hexenyl, 3-hexenyl, 5-hexenyl, and 2-cyclohexenyl groups.

[0027] The substituents on the alkyl group in "substituted or unsubstituted alkyl group" and the alkenyl group in "substituted or unsubstituted alkenyl group" are not particularly limited, but examples include halogen atoms, cyano groups, nitro groups, alkyl-oxy groups, alkyl-carbonyl groups, alkyl-oxy-carbonyl groups, alkyl-carbonyl-oxy groups, alkenyl-oxy groups, alkenyl-carbonyl groups, alkenyl-oxy-carbonyl groups, alkenyl-carbonyl-oxy groups, aryl groups, aryl-oxy groups, aryl-carbonyl groups, aryl-oxy-carbonyl groups, aryl-carbonyl-oxy groups, etc., or combinations thereof. The number of substituents is preferably 1 to 3, and more preferably 1.

[0028] An "aryl group" refers to a monovalent aromatic hydrocarbon group. Preferably, the aryl group has 6 to 14 carbon atoms. Examples of aryl groups include phenyl, 1-naphthyl, and 2-naphthyl groups.

[0029] The substituents on the aryl group in "substituted or unsubstituted aryl group" are not particularly limited, but examples include halogen atoms, cyano groups, nitro groups, alkyl groups, alkyl-oxy groups, alkyl-carbonyl groups, alkyl-oxy-carbonyl groups, alkyl-carbonyl-oxy groups, alkenyl groups, alkenyl-oxy groups, alkenyl-carbonyl groups, alkenyl-oxy-carbonyl groups, alkenyl-carbonyl-oxy groups, aryl groups, aryl-alkyl groups, aryl-alkenyl groups, aryl-oxy groups, aryl-carbonyl groups, aryl-oxy-carbonyl groups, aryl-carbonyl-oxy groups, etc., or combinations thereof. The number of substituents is preferably 1 to 3, and more preferably 1.

[0030] Examples of "halogen atoms" include fluorine atoms, chlorine atoms, and bromine atoms.

[0031] In equation (A1), R 1 Each of these independently represents an epoxyalkyl group, preferably a linear alkyl group having a cyclic epoxyalkyl group at its terminus, more preferably a methyl group having a cyclic epoxyalkyl group, or an ethyl group having a cyclic epoxyalkyl group at its terminus, and particularly preferably a 2-(3,4-epoxycyclohexyl)ethyl group.

[0032] In equation (A1), R 2 Each of these independently represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, or a substituted or unsubstituted aryl group, preferably a substituted or unsubstituted alkyl group, more preferably an (unsubstituted) alkyl group, even more preferably a methyl group, an ethyl group, a propyl group, or an isopropyl group, and particularly preferably a methyl group.

[0033] In equation (A1), R 3 and R 4 Each independently represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, or a substituted or unsubstituted aryl group, or R 3and R 4 These molecules combine to form a single -O- group, bonding with each other to create a cyclic siloxane skeleton. 3 and R 4 Preferably, they combine to form a cyclic siloxane skeleton by bonding with each other and showing a single -O-.

[0034] In formula (A1), s represents an integer of 1 or more, preferably an integer of 2 or more. s is preferably an integer of 9 or less, more preferably an integer of 7 or less, even more preferably an integer of 5 or less, and even more preferably an integer of 4 or less. Particularly preferably, s is 3.

[0035] (A-1) Specific examples of siloxane skeleton-containing epoxy resins include 1,3,5-tris(2-(3,4-epoxycyclohexyl)ethyl)-1,1,3,5,5-pentamethyltrisiloxane and other chain-like siloxane skeleton-containing epoxy resins; 2,4,6,8-tetrakis(4-(3,4-epoxycyclopentyl)butyl)-2,4,6,8-tetramethylcyclotetrasiloxane and 2,4,6,8-tetrakis(3-(3,4-epoxycyclopentyl)propyl)-2,4,6,8-tetramethylcyclotetrasiloxane Examples include epoxy resins containing a cyclic siloxane skeleton, such as 2,4,6,8-tetrakis(2-(3,4-epoxycyclohexyl)ethyl)-2,4,6,8-tetramethylcyclotetrasiloxane and 2,4,6,8,10-pentakis(2-(3,4-epoxycyclohexyl)ethyl)-2,4,6,8,10-pentamethylcyclopentasiloxane, among which 2,4,6,8-tetrakis(2-(3,4-epoxycyclohexyl)ethyl)-2,4,6,8-tetramethylcyclotetrasiloxane is particularly preferred.

[0036] (A-1) Examples of commercially available epoxy resins containing a siloxane skeleton include "KR-470" (main component: 2,4,6,8-tetrakis(2-(3,4-epoxycyclohexyl)ethyl)-2,4,6,8-tetramethylcyclotetrasiloxane) and "X-40-2667" (main component: 1,3,5-tris(2-(3,4-epoxycyclohexyl)ethyl)-1,1,3,5,5-pentamethyltrisiloxane) manufactured by Shin-Etsu Chemical Co., Ltd.

[0037] (A-1) The molecular weight of the siloxane skeleton-containing epoxy resin is preferably 2,000 or less, more preferably 1,500 or less, even more preferably 1,000 or less, and particularly preferably 800 or less. The lower limit can be, for example, 200 or more, 400 or more, 600 or more, etc.

[0038] (A-1) The epoxy equivalent of the siloxane skeleton-containing epoxy resin is preferably 1,000 g / eq. or less, more preferably 500 g / eq. or less, even more preferably 300 g / eq. or less, and particularly preferably 250 g / eq. or less. The lower limit is preferably 50 g / eq. or more, more preferably 100 g / eq. or more, even more preferably 130 g / eq. or more, and particularly preferably 150 g / eq. or more.

[0039] (A-1) The viscosity (at 25°C) of the siloxane skeleton-containing epoxy resin is preferably 100 mPa·s to 10,000 mPa·s, more preferably 1,000 mPa·s to 5,000 mPa·s.

[0040] The content of (A-1)siloxane skeleton-containing epoxy resin in the resin composition is not particularly limited, but is preferably 1% by mass or more, more preferably 3% by mass or more, even more preferably 4% by mass or more, and particularly preferably 5% by mass or more, when the nonvolatile components in the resin composition are taken as 100% by mass. The upper limit of the content of (A-1)siloxane skeleton-containing epoxy resin in the resin composition is not particularly limited, but is preferably 30% by mass or less, more preferably 20% by mass or less, even more preferably 15% by mass or less, and particularly preferably 10% by mass or less, when the nonvolatile components in the resin composition are taken as 100% by mass.

[0041] <Any epoxy resin other than component (A-1)> (A) The epoxy resin may contain (A-1) a siloxane skeleton-containing epoxy resin, plus any other epoxy resin.

[0042] Examples of epoxy resins other than component (A-1) 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, 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, glycidylcyclohexane-type epoxy resin, and the like. Any epoxy resin may be used alone or in combination of two or more types.

[0043] The resin composition preferably includes an epoxy resin having two or more epoxy groups per molecule as an optional epoxy resin other than component (A-1). The proportion of the epoxy resin having two or more epoxy groups per molecule is preferably 50% by mass or more, more preferably 60% by mass or more, and particularly preferably 70% by mass or more, relative to 100% by mass of the nonvolatile component of the optional epoxy resin other than component (A-1).

[0044] 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 or only solid epoxy resin as any epoxy resin other than component (A-1), but it is preferable to contain a combination of liquid epoxy resin and solid epoxy resin.

[0045] As the liquid epoxy resin, a liquid epoxy resin having two or more epoxy groups in one molecule is preferred.

[0046] Preferred liquid epoxy resins include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AF type epoxy resin, naphthalene type epoxy resin, glycidyl ester type epoxy resin, glycidylamine type epoxy resin, phenol novolac type epoxy resin, alicyclic epoxy resin having an ester skeleton, cyclohexane type epoxy resin, cyclohexanedimethanol type epoxy resin, and epoxy resin having a butadiene structure.

[0047] Specific examples of liquid epoxy resins include DIC's "HP4032," "HP4032D," and "HP4032SS" (naphthalene-type epoxy resin); Mitsubishi Chemical's "828US," "828EL," "jER828EL," "825," and "Epicote 828EL" (bisphenol A-type epoxy resin); Mitsubishi Chemical's "jER807" and "1750" (bisphenol F-type epoxy resin); Mitsubishi Chemical's "jER152" (phenol novolac-type epoxy resin); Mitsubishi Chemical's "630," "630LSD," and "604" (glycidylamine-type epoxy resin); ADEKA's "ED-523T" (glycyrrhizol-type epoxy resin); and ADEKA's "EP-3950L." Examples include "EP-3980S" (glycidylamine type epoxy resin); "EP-4088S" (dicyclopentadiene type epoxy resin) from ADEKA Corporation; "ZX1059" (a mixture of bisphenol A type epoxy resin and bisphenol F type epoxy resin) from Nippon Steel & Sumitomo Metal Chemical Corporation; "EX-721" (glycidyl ester type epoxy resin) from Nagase ChemteX Corporation; "Celoxide 2021P" (alicyclic epoxy resin with an ester skeleton) from Daicel Corporation; "PB-3600" from Daicel Corporation; "JP-100" and "JP-200" (epoxy resins with a butadiene structure) from Nippon Soda Co., Ltd.; and "ZX1658" and "ZX1658GS" (cyclohexane type epoxy resins) from Nippon Steel & Sumitomo Metal Chemical Corporation. These can be used individually or in combination of two or more types.

[0048] 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.

[0049] Preferred solid epoxy resins include bixylenol-type epoxy resin, naphthalene-type epoxy resin, naphthalene-type tetrafunctional epoxy resin, cresol novolac-type epoxy resin, dicyclopentadiene-type epoxy resin, trisphenol-type epoxy resin, naphthol-type epoxy resin, biphenyl-type epoxy resin, naphthylene ether-type epoxy resin, anthracene-type epoxy resin, bisphenol A-type epoxy resin, bisphenol AF-type epoxy resin, and tetraphenylethane-type epoxy resin.

[0050] 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", and "HP-7200H" (dicyclopentadiene-type epoxy resins); and DIC's "EXA-731" 1", "EXA-7311-G3", "EXA-7311-G4", "EXA-7311-G4S", "HP6000" (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. "ESN475V" (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 of epoxy resins include: Mitsubishi Chemical's "YX7700" (xylene structure-containing novolac type epoxy resin); Osaka Gas Chemical's "PG-100" and "CG-500"; Mitsubishi Chemical's "YL7760" (bisphenol AF type epoxy resin); Mitsubishi Chemical's "YL7800" (fluorene type epoxy resin); Mitsubishi Chemical's "jER1010" (solid bisphenol A type epoxy resin); and Mitsubishi Chemical's "jER1031S" (tetraphenylethane type epoxy resin). These can be used individually or in combination of two or more types.

[0051] When using a combination of liquid epoxy resin and solid epoxy resin as any epoxy resin other than component (A-1), the mass ratio of the liquid epoxy resin to the solid epoxy resin is preferably in the range of 100:1 to 1:100, more preferably in the range of 10:1 to 1:40, and even more preferably in the range of 1:1 to 1:20.

[0052] The epoxy equivalent of any epoxy resin other than component (A-1) 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. Epoxy equivalent is the mass of resin per equivalent of epoxy groups. This epoxy equivalent can be measured according to JIS K7236.

[0053] The weight-average molecular weight (Mw) of any epoxy resin other than component (A-1) 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).

[0054] If the resin composition contains any epoxy resin other than component (A-1), the content of any epoxy resin other than component (A-1) 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 5% by mass or more, more preferably 10% by mass or more, even more preferably 15% by mass or more, and particularly preferably 20% by mass or more. The upper limit of the content of any epoxy resin other than component (A-1) 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 60% by mass or less, more preferably 50% by mass or less, even more preferably 40% by mass or less, and particularly preferably 30% by mass or less.

[0055] When the resin composition contains any epoxy resin other than component (A-1), the content of (A-1) siloxane skeleton-containing epoxy resin in (A) epoxy resin is not particularly limited, but is preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 15% by mass or more, and particularly preferably 20% by mass or more, when the total amount of (A) epoxy resin is 100% by mass. The upper limit of the content of (A-1) siloxane skeleton-containing epoxy resin in (A) epoxy resin is not particularly limited, but is preferably 50% by mass or less, more preferably 40% by mass or less, even more preferably 30% by mass or less, and particularly preferably 25% by mass or less, when the total amount of (A) epoxy resin is 100% by mass.

[0056] <(B) Inorganic filler> The resin composition of the present invention contains (B) an inorganic filler. (B) The inorganic filler is included in the resin composition in the form of particles.

[0057] (B) Inorganic compounds are used as the material for the inorganic filler. (B) Examples of materials for the 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, synthetic silica, and hollow silica. Spherical silica is preferred as the silica. (B) The inorganic filler may be used alone or in combination of two or more types in any ratio.

[0058] (B) Examples of commercially available inorganic fillers include "SP60-05" and "SP507-05" from Nippon Steel & Sumitomo Metal Materials; "YC100C", "YA050C", "YA050C-MJE", and "YA010C" from Admatex Corporation; "Silfil NSS-3N", "Silfil NSS-4N", and "Silfil NSS-5N" from Tokuyama Corporation; "SC2500SQ", "SO-C4", "SO-C2", and "SO-C1" from Admatex Corporation; and "UFP-30", "DAW-03", and "FB-105FD" from Denka Corporation.

[0059] (B) The average particle size of the inorganic filler is not particularly limited, but is preferably 40 μm or less, more preferably 10 μm or less, even more preferably 5 μm or less, even more preferably 3 μm or less, and especially preferably 1 μm or less. (B) The lower limit of the average particle size of the inorganic filler is not particularly limited, but is preferably 0.005 μm or more, more preferably 0.01 μm or more, even more preferably 0.05 μm or more, even more preferably 0.1 μm or more, even more preferably 0.2 μm or more, and especially preferably 0.3 μm or more. (B) 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 median diameter can be used as the average particle size. A sample can be prepared by weighing 100 mg of inorganic filler and 10 g of methyl ethyl ketone into a vial and dispersing them with 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.

[0060] (B) The specific surface area of ​​the 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 1m2 / g or more, particularly preferably 5m 2 (B) The upper limit of the specific surface area of ​​the inorganic filler is not particularly limited, but preferably 50 m². 2 / g or less, more preferably 30m 2 / g or less, more preferably 20m 2 / g or less, particularly preferably 15m 2 The value is less than / g. 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.

[0061] (B) The inorganic filler is preferably surface-treated with an appropriate surface treatment agent. Surface treatment can improve the moisture resistance and dispersibility of the inorganic filler (B). Examples of surface treatment agents include vinyl-based silane coupling agents such as vinyltrimethoxysilane and vinyltriethoxysilane; epoxy-based silane coupling agents such as 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, and 3-glycidoxypropyltriethoxysilane; styryl-based silane coupling agents such as p-styryltrimethoxysilane; methacryl-based silane coupling agents such as 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, and 3-methacryloxypropyltriethoxysilane; acrylic-based silane coupling agents such as 3-acryloxypropyltrimethoxysilane; and N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane and N-2-(aminoethyl)-3-aminopropyl Amino-based silane coupling agents such as dimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethylbutylidene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-8-aminooctyltrimethoxysilane, N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane; isocyanurate-based silane coupling agents such as tris-(trimethoxysilylpropyl)isocyanurate; ureido-based silane coupling agents such as 3-ureidopropyltrialkoxysilane; mercapto-based silane coupling agents such as 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane; isocyanate-based silane coupling agents such as 3-isocyanatetopropyltriethoxysilane; acid anhydride-based silane coupling agents such as 3-trimethoxysilylpropylsuccinic anhydride; and other silane coupling agents.Examples include non-silane coupling alkoxysilane compounds such as methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, octyltriethoxysilane, decyltrimethoxysilane, 1,6-bis(trimethoxysilyl)hexane, and trifluoropropyltrimethoxysilane. Among these, amino-based silane coupling agents are preferred. The surface treatment agent may be used alone or in combination of two or more agents in any ratio.

[0062] Examples of commercially available surface treatment agents include, for example, Shin-Etsu Chemical Co., Ltd.'s "KBM-1003," "KBE-1003" (vinyl-based silane coupling agent); "KBM-303," "KBM-402," "KBM-403," "KBE-402," "KBE-403" (epoxy-based silane coupling agent); "KBM-1403" (styryl-based silane coupling agent); "KBM-502," "KBM-503," "KBE-502," "KBE-503" (methacrylic-based silane coupling agent); "KBM-5103" (acrylic-based silane coupling agent); "KBM-602," "KBM-603," "KBM-903," "KBE-903," "KBE-9103P," "KBM-573," and "KBM-575" (amino-based silane coupling agent); Examples include "KBM-9659" (isocyanurate-based silane coupling agent), "KBE-585" (ureido-based silane coupling agent), "KBM-802", "KBM-803" (mercapto-based silane coupling agent), "KBE-9007N" (isocyanate-based silane coupling agent), "X-12-967C" (acid anhydride-based silane coupling agent), "KBM-13", "KBM-22", "KBM-103", "KBE-13", "KBE-22", "KBE-103", "KBM-3033", "KBE-3033", "KBM-3063", "KBE-3063", "KBE-3083", "KBM-3103C", "KBM-3066", and "KBM-7103" (non-silane coupling - alkoxysilane compounds).

[0063] From the viewpoint of improving the dispersibility of the inorganic filler, the degree of surface treatment by the surface treatment agent is preferably within a predetermined range. Specifically, 100% by mass of the inorganic filler is preferably surface-treated with 0.2% to 5% by mass of the surface treatment agent, more preferably with 0.2% to 3% by mass, and even more preferably with 0.3% to 2% by mass.

[0064] 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. From the viewpoint of improving the dispersibility of the inorganic filler, the amount of carbon per unit surface area of ​​the inorganic filler should be 0.02 mg / m². 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 are even more preferable.

[0065] (B) The amount of carbon per unit surface area of ​​the inorganic filler can be measured after cleaning the inorganic filler with a solvent (e.g., methyl ethyl ketone (MEK)) following 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, a Horiba "EMIA-320V" or similar can be used.

[0066] The content of (B) inorganic filler in the resin composition is 40% by mass or less, preferably 38% by mass or less, more preferably 36% by mass or less, even more preferably 34% by mass or less, and particularly preferably 32% by mass or less, when the nonvolatile components in the resin composition are taken as 100% by mass. The lower limit of the content of (B) inorganic filler in the resin composition is not particularly limited, but preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 20% by mass or more, and particularly preferably 30% by mass or more, when the nonvolatile components in the resin composition are taken as 100% by mass.

[0067] (C) Polyimide resin The resin composition of the present invention comprises (C) polyimide resin. (C) polyimide resin is a resin having imide bonds in its repeating units. (C) polyimide resin generally includes (1) a resin obtained by an imidation reaction between a diamine compound and a tetracarboxylic anhydride, or (2) a resin obtained by an imidation reaction between a diisocyanate compound and a tetracarboxylic anhydride. (C) polyimide resin also includes modified polyimide resins such as siloxane-modified polyimide resins.

[0068] (C) Polyimide resin is not particularly limited, but for example, formula (C1):

[0069] [ka]

[0070] [In the formula, X 1 This represents a tetravalent group obtained by removing two -CO-O-CO- groups from a tetracarboxylic dianhydride, and may be an organic group consisting of two or more skeletal atoms selected from carbon, oxygen, nitrogen, and sulfur atoms (e.g., 2-3,000, 2-1,000, 2-100, 2-50). 2 X represents a divalent group obtained by removing two -NH2 groups from a diamine compound, or a divalent group obtained by removing two -NCO groups from a diisocyanate compound, and may be an organic group consisting of two or more (e.g., 2-3,000, 2-1,000, 2-100, 2-50) skeletal atoms selected from carbon, oxygen, nitrogen, and sulfur atoms. n represents an integer of 2 or more. It may include structures represented by ]. X in formula (C1) 1 and X 2 The organic group is not particularly limited as long as it is within the range of chemically stable structures, and is a structure that can be appropriately selected by those skilled in the art, for example, it may be a structure of a known polyimide resin. (C) If the polyimide resin contains a structure represented by formula (C1), it is preferable that it contains 60% by mass or more of the structure represented by formula (C1), more preferably 80% by mass or more, even more preferably 90% by mass or more, and particularly preferably 95% by mass or more.

[0071] (C) The diamine compounds used to prepare the polyimide resin are not particularly limited, but examples include aliphatic diamine compounds and aromatic diamine compounds.

[0072] Examples of aliphatic diamine compounds include linear aliphatic diamine compounds such as 1,2-ethylenediamine, 1,2-diaminopropane, 1,3-diaminopropane, 1,4-diaminobutane, 1,6-hexamethylenediamine, 1,5-diaminopentane, and 1,10-diaminodecane; branched aliphatic diamine compounds such as 1,2-diamino-2-methylpropane, 2,3-diamino-2,3-butane, and 2-methyl-1,5-diaminopentane; alicyclic diamine compounds such as 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, 1,4-diaminocyclohexane, and 4,4'-methylenebis(cyclohexylamine); and dimer acid type diamines (hereinafter also referred to as "dimer amines").

[0073] Dimer acid-type diamines refer to diamine compounds obtained by substituting the two terminal carboxyl groups (-COOH) of a dimer acid with aminomethyl groups (-CH2-NH2) or amino groups (-NH2). Dimer acid is a known compound obtained by dimerizing unsaturated fatty acids (preferably those with 11 to 22 carbon atoms, particularly preferably those with 18 carbon atoms), and its industrial production process is largely standardized in the industry. Dimer acid is readily available, especially those mainly composed of 36-carbon dimer acid obtained by dimerizing 18-carbon unsaturated fatty acids such as oleic acid and linoleic acid, which are inexpensive and readily available. Dimer acid may also contain arbitrary amounts of monomeric acids, trimeric acids, and other polymerized fatty acids depending on the production method and degree of purification. Furthermore, although double bonds remain after the polymerization reaction of unsaturated fatty acids, in this specification, hydrogenated products obtained by further hydrogenation to reduce the degree of unsaturation are also included as dimer acid. Dimer acid type diamines are commercially available, such as "PRIAMINE1073," "PRIAMINE1074," and "PRIAMINE1075" from Croda Japan, and "Versamin 551" and "Versamin 552" from Cognis Japan.

[0074] Aromatic diamine compounds include, for example, phenylenediamine compounds such as 1,4-phenylenediamine, 1,2-phenylenediamine, 1,3-phenylenediamine, 2,4-diaminotoluene, 2,6-diaminotoluene, 3,5-diaminobiphenyl, and 2,4,5,6-tetrafluoro-1,3-phenylenediamine; naphthalenediamine compounds such as 1,5-diaminonaphthalene, 1,8-diaminonaphthalene, 2,6-diaminonaphthalene, and 2,3-diaminonaphthalene; and 4,4'-diamino-2,2' -Ditrifluoromethyl-1,1'-biphenyl, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfide, 4-aminophenyl-4-aminobenzoate, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 2,2-bis(4-aminophenyl)propane 4,4'-(hexafluoroisopropylidene)dianiline, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, α,α-bis[4-(4-aminophenoxy)phenyl]-1,3-diisopropylbenzene, α,α-bis[4-(4-aminophenoxy)phenyl]-1,4-diisopropylbenzene, 4,4'-(9-fluorenylidene)dianiline, 2,2-bis(3-methyl-4-aminophenoxy Examples include dianiline compounds such as propane, 2,2-bis(3-methyl-4-aminophenyl)benzene, 4,4'-diamino-3,3'-dimethyl-1,1'-biphenyl, 4,4'-diamino-2,2'-dimethyl-1,1'-biphenyl, 9,9'-bis(3-methyl-4-aminophenyl)fluorene, 5-(4-aminophenoxy)-3-[4-(4-aminophenoxy)phenyl]-1,1,3-trimethylindan, and 5-amino-1,1'-biphenyl-2-yl 4-aminobenzoate.

[0075] The diamine compound may be a commercially available one or one synthesized by a known method. The diamine compound may be used alone or in combination of two or more.

[0076] (C) The diisocyanate compound for preparing the polyimide resin is not particularly limited, but examples include aliphatic diisocyanate compounds, aromatic diisocyanate compounds, and polyurethanes with isocyanate groups at both ends.

[0077] Examples of aliphatic diisocyanate compounds include linear aliphatic diisocyanate compounds such as tetramethylene diisocyanate, hexamethylene diisocyanate, octamethylene diisocyanate, and dodecamethylene diisocyanate; branched aliphatic diisocyanate compounds such as 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, and 2,2-dimethylpentamethylene diisocyanate; isophorone diisocyanate (IPDI), 1,4-cyclohexyl Examples include alicyclic diisocyanate compounds such as diisocyanates (CHDI), 4-methyl-1,3-cyclohexylene diisocyanate, 2-methyl-1,3-cyclohexylene diisocyanate, 2-methyl-1,4-cyclohexylene diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, and 3a,4,5,6,7,7a-hexahydro-4,7-methanoindan-1,8-ylene diisocyanate; and dimer acid type diisocyanates.

[0078] Dimer acid type diisocyanates refer to diisocyanate compounds obtained by substituting the amino group (-NH2) of the dimer acid type diamine described above with an isocyanate group (-NCO).

[0079] Examples of aromatic diisocyanate compounds include phenylene diisocyanate compounds such as 1,4-phenylene diisocyanate, 1,3-phenylene diisocyanate, torylene-2,6-diisocyanate, torylene-2,4-diisocyanate, and torylene-3,5-diisocyanate; naphthalene diisocyanate compounds such as 1,3-naphthalene diisocyanate, 1,6-naphthalene diisocyanate, 1,7-naphthalene diisocyanate, 1,8-naphthalene diisocyanate, 2,6-naphthalene diisocyanate, and 2,7-naphthalene diisocyanate; and bisisocyanatobenzene compounds such as 4,4'-diphenylmethane diisocyanate and 4,4'-diphenyl ether diisocyanate.

[0080] Polyurethanes with isocyanate groups at both ends may be obtained by urethane-forming an aliphatic diisocyanate compound and / or aromatic diisocyanate compound as described above with a polymer with hydroxyl groups at both ends. Examples of polymers with hydroxyl groups at both ends include polyolefins with hydroxyl groups at both ends such as polybutadiene with hydroxyl groups at both ends, hydrogenated polybutadiene with hydroxyl groups at both ends, polyisoprene with hydroxyl groups at both ends, and hydrogenated polyisoprene with hydroxyl groups at both ends; and polyethers with hydroxyl groups at both ends such as polyethylene glycol with hydroxyl groups at both ends, polypropylene glycol with hydroxyl groups at both ends, and polytetramethylene glycol with hydroxyl groups at both ends.

[0081] The number-average molecular weight of the hydroxyl group polymers at both ends is not particularly limited, but is preferably 500 or more, more preferably 1,000 or more, and even more preferably 2,000 or more. The upper limit of the number-average molecular weight of the hydroxyl group polymers at both ends is not particularly limited, but is preferably 10,000 or less, and more preferably 8,000 or less. The number-average molecular weights here are values ​​measured by gel permeation chromatography (GPC) (in polystyrene equivalent).

[0082] Polyurethanes with isocyanate groups at both ends include, for example, those of formula (C2):

[0083] [ka]

[0084] [In the formula, X 2a Each of these independently represents a divalent group obtained by removing two -NCO groups from an aliphatic diisocyanate compound or an aromatic diisocyanate compound, and may be an organic group consisting of 2 to 50 skeletal atoms selected from carbon, oxygen, nitrogen, and sulfur atoms. 2b Each of these independently represents a divalent group obtained by removing two -OH groups from the hydroxyl group polymer at both ends, and can be an organic group consisting of two or more (e.g., 2 to 1,000 and 2 to 500) skeletal atoms selected from carbon atoms and oxygen atoms. m represents an integer from 1 to 10. This is a polyurethane with isocyanate groups at both ends represented by ].

[0085] The diisocyanate compound may be a commercially available product, or one synthesized by a known method or a similar method. The diisocyanate compound may be used alone, or two or more may be used in combination.

[0086] (C) The tetracarboxylic anhydrides used to prepare the polyimide resin are not particularly limited, but examples include aliphatic tetracarboxylic dianhydrides and aromatic tetracarboxylic dianhydrides.

[0087] Examples of aliphatic tetracarboxylic dianhydrides include 1,2,3,4-cyclobutanetetracarboxylic dianhydride, cyclopentanetetracarboxylic dianhydride, cyclohexane-1,2,3,4-tetracarboxylic dianhydride, cyclohexane-1,2,4,5-tetracarboxylic dianhydride, 3,3',4,4'-bicyclohexyltetracarboxylic dianhydride, carbonyl-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, methylene-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, 1,2-ethylene-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, oxy-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, thio-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, and sulfonyl-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride.

[0088] Examples of aromatic tetracarboxylic dianhydrides include benzenetetracarboxylic dianhydrides such as pyromellitic acid dianhydride and 1,2,3,4-benzenetetracarboxylic dianhydride; naphthalenetetracarboxylic dianhydrides such as 1,4,5,8-naphthalenetetracarboxylic dianhydride and 2,3,6,7-naphthalenetetracarboxylic dianhydride; anthracenetetracarboxylic dianhydrides such as 2,3,6,7-anthracenetetracarboxylic dianhydride; and 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 3,3' ,4,4'-diphenyl ether tetracarboxylic dianhydride, 3,3',4,4'-diphenyl sulfone tetracarboxylic dianhydride, 3,3',4,4'-biphenyl tetracarboxylic dianhydride, 2,2',3,3'-biphenyl tetracarboxylic dianhydride, 2,3,3',4'-biphenyl tetracarboxylic dianhydride, 2,3,3',4'-benzophenone tetracarboxylic dianhydride, 2,3,3',4'-diphenyl ether tetracarboxylic dianhydride, 2,3,3',4'-diphenyl sulfone tetracarboxylic dianhydride Diphthalic acid dianhydride 2,2'-bis(3,4-dicarboxyphenoxyphenyl)sulfone dianhydride, methylene-4,4'-diphthalic acid dianhydride, 1,1-ethynylidene-4,4'-diphthalic acid dianhydride, 2,2-propyridene-4,4'-diphthalic acid dianhydride, 1,2-ethylene-4,4'-diphthalic acid dianhydride, 1,3-trimethylene-4,4'-diphthalic acid dianhydride, 1,4-tetramethylene-4,4'-diphthalic acid dianhydride, 1,5-pentamethylene-4,4'-diphthalic acid dianhydride, 1,3-bis(3,4-di Examples include diphthalic acid dianhydrides such as carboxyphenyl)benzene dianhydride, 1,4-bis(3,4-dicarboxyphenyl)benzene dianhydride, 1,3-bis(3,4-dicarboxyphenoxy)benzene dianhydride, 1,4-bis(3,4-dicarboxyphenoxy)benzene dianhydride, 2,2-bis(2,3-dicarboxyphenyl)propane dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, and 4,4'-(4,4'-isopropylidenediphenoxy)bisphthalic acid dianhydride.

[0089] The tetracarboxylic dianhydride may be a commercially available product, or it may be synthesized by a known method or a similar method. The tetracarboxylic dianhydride may be used alone, or two or more may be used in combination.

[0090] (C) The content of the structure derived from aromatic tetracarboxylic dianhydride relative to the total structure derived from tetracarboxylic dianhydride constituting the polyimide resin is preferably 10 mol% or more, more preferably 30 mol% or more, even more preferably 50 mol% or more, still more preferably 70 mol% or more, still more preferably 90 mol% or more, and particularly preferably 100 mol%.

[0091] (C) The weight-average molecular weight of the polyimide resin is not particularly limited, but is preferably 1,000 or more, more preferably 3,000 or more, even more preferably 5,000 or more, and especially preferably 7,000 or more. (C) The upper limit of the weight-average molecular weight of the polyimide resin is not particularly limited, but is preferably 100,000 or less, more preferably 80,000 or less, especially preferably 60,000 or less, and especially preferably 50,000 or less.

[0092] (C) The number average molecular weight of the polyimide resin is not particularly limited, but is preferably 1,000 or more, more preferably 3,000 or more, even more preferably 5,000 or more, and especially preferably 7,000 or more. (C) The upper limit of the number average molecular weight of the polyimide resin is not particularly limited, but is preferably 100,000 or less, more preferably 80,000 or less, especially preferably 60,000 or less, and especially preferably 50,000 or less.

[0093] The content of (C) polyimide resin 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 more, more preferably 10% by mass or more, even more preferably 15% by mass or more, and particularly preferably 20% by mass or more. The upper limit of the content of (C) polyimide resin 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 50% by mass or less, more preferably 40% by mass or less, even more preferably 35% by mass or less, and particularly preferably 30% by mass or less.

[0094] <(D) Hardener> The resin composition of the present invention may further contain (D) a curing agent. The curing agent (D) has the function of curing the epoxy resin (A).

[0095] (D) The curing agent is not particularly limited, but examples include phenolic curing agents, naphthol curing agents, acid anhydride curing agents, activated ester curing agents, benzoxazine curing agents, cyanate ester curing agents, and carbodiimide curing agents. The curing agent may be used alone or in combination of two or more. (D) The curing agent preferably contains a curing agent selected from phenolic curing agents, naphthol curing agents, and activated ester curing agents, and it is particularly preferable that it contains an activated ester curing agent.

[0096] From the viewpoint of heat resistance and water resistance, phenolic curing agents having a novolac structure or naphthol curing agents having a novolac structure are preferred as phenolic curing agents and naphthol curing agents. Furthermore, from the viewpoint of adhesion to the adherend, nitrogen-containing phenolic curing agents or nitrogen-containing naphthol curing agents are preferred, and triazine skeleton-containing phenolic curing agents or triazine skeleton-containing naphthol curing agents are more preferred. Among these, triazine skeleton-containing phenol novolac resins are preferred from the viewpoint of highly satisfying heat resistance, water resistance, and adhesion. Specific examples of phenol-based and naphthol-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 "TD-2090-60M" from DIC Corporation.

[0097] 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 of acid anhydrides 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 copolymerized with styrene and maleic acid. Commercially available acid anhydride-based curing agents include "HNA-100" and "MH-700" manufactured by Shin Nippon Rika Co., Ltd.

[0098] While there are no particular restrictions on the active ester curing agent, 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 curing agent 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 curing agent obtained from a carboxylic acid compound and a hydroxy compound is preferred, and an active ester curing agent 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.

[0099] Specifically, active ester compounds containing a dicyclopentadiene-type diphenol structure, active ester compounds containing a naphthalene structure, active ester compounds containing an acetylated phenol novolac, and active ester compounds containing a benzoylated phenol novolac are preferred, with active ester compounds containing a naphthalene structure and active ester compounds containing a dicyclopentadiene-type diphenol structure being more preferred. "Dicyclopentadiene-type diphenol structure" refers to a divalent structural unit consisting of phenylene-dicyclopentalene-phenylene.

[0100] Commercially available active ester curing agents include active ester compounds containing a dicyclopentadiene-type diphenol structure, such as "EXB9451", "EXB9460", "EXB9460S", "HPC-8000", "HPC-8000H", "HPC-8000-65T", "HPC-8000H-65TM", "EXB-8000L", "EXB-8000L-65M", and "EXB-8000L-65TM" (manufactured by DIC Corporation); and active ester compounds containing a naphthalene structure, such as "EXB Examples include "-9416-70BK", "EXB-8150-65T", "EXB-8100L-65T", and "EXB-8150L-65T" (manufactured by DIC Corporation); "DC808" (manufactured by Mitsubishi Chemical Corporation) is an active ester curing agent that is an acetylated phenol novolac; and "YLH1026" (manufactured by Mitsubishi Chemical Corporation), "YLH1030" (manufactured by Mitsubishi Chemical Corporation), and "YLH1048" (manufactured by Mitsubishi Chemical Corporation) are active ester curing agents that are benzoylated phenol novolacs.

[0101] 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.

[0102] 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).

[0103] Specific examples of carbodiimide-based curing agents include "V-03" and "V-07" manufactured by Nisshinbo Chemical Co., Ltd.

[0104] When the resin composition contains a curing agent (D), the ratio of (A) epoxy resin to (D) curing agent is preferably 1:0.2 to 1:2, more preferably 1:0.3 to 1:1.5, and even more preferably 1:0.4 to 1:1.4, in the ratio of [(A) epoxy resin]:[(D) curing agent]. Here, the reacting group of the curing agent (D) is, for example, an aromatic hydroxyl group for phenolic and naphthol-based curing agents, and an active ester group for active ester-based curing agents, and varies depending on the type of curing agent.

[0105] (D) The reactive group equivalent of the curing agent is preferably 50 g / eq. to 3,000 g / eq., more preferably 100 g / eq. to 1,000 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 the curing agent per equivalent of one reactive group.

[0106] (D) When the curing agent contains an active ester-based curing agent, the amount is not particularly limited, but when the total amount of (D) curing agent is 100% by mass, it is preferably 10% by mass or more, more preferably 20% by mass or more, even more preferably 30% by mass or more, and particularly preferably 40% by mass or more.

[0107] When the resin composition contains a curing agent (D), the content of the curing agent (D) in the resin composition is not particularly limited, but is preferably 1% by mass or more, more preferably 3% by mass or more, even more preferably 4% by mass or more, and particularly preferably 5% by mass or more, when the nonvolatile components in the resin composition are taken as 100% by mass. The upper limit of the content of the curing agent (D) in the resin composition is not particularly limited, but is preferably 20% by mass or less, more preferably 15% by mass or less, even more preferably 10% by mass or less, and particularly preferably 8% by mass or less, when the nonvolatile components in the resin composition are taken as 100% by mass.

[0108] <(E) Curing accelerator> The resin composition of the present invention may optionally contain (E) a curing accelerator. The (E) curing accelerator has the function of accelerating the curing of (A) epoxy resin.

[0109] (E) The curing accelerator is not particularly limited, but examples include phosphorus-based curing accelerators, urea-based curing accelerators, amine-based curing accelerators, imidazole-based curing accelerators, guanidine-based curing accelerators, and metal-based curing accelerators. Among these, phosphorus-based curing accelerators, amine-based curing accelerators, imidazole-based curing accelerators, and metal-based curing accelerators are preferred, and imidazole-based curing accelerators are particularly preferred. The curing accelerator may be used alone or in combination of two or more types.

[0110] 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 cresol novolac trimer, and di-tert-butylmethylphosphonium tetraphenylborate; methyltriphenylphosphonium bromide, ethyltriphenylphosphonium bromide, propyltriphenylphosphonium bromide, butyltriphenylphosphonium bromide, benzyltriphenylphosphonium chloride, tetraphenylphosphonium bromide, p-tolyltriphenylphosphonium tetra-p-tolylborate, and tetraphenylphosphonium tetraphenylborate. Aromatic phosphonium salts such as 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.

[0111] 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.

[0112] Examples of amine-based curing accelerators include trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine (DMAP), benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, and 1,8-diazabicyclo(5,4,0)-undecene, with 4-dimethylaminopyridine being preferred.

[0113] 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.

[0114] Commercial imidazole-based curing accelerators may be used, such as "P200-H50" manufactured by Mitsubishi Chemical Corporation.

[0115] 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.

[0116] 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.

[0117] When the resin composition contains (E) a curing accelerator, the content of (E) the 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 0.001% by mass or more, more preferably 0.01% by mass or more, even more preferably 0.05% by mass or more, and particularly preferably 0.1% by mass or more. The upper limit of the content of (E) the 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 3% by mass or less, even more preferably 1% by mass or less, and particularly preferably 0.5% by mass or less.

[0118] <(F) Other additives> The resin composition of the present invention may further contain any additives as non-volatile components. Examples of such additives include: organic fillers such as rubber particles, polyamide fine particles, and silicone particles; thermoplastic resins such as phenoxy resin, polyvinyl acetal resin, polyolefin resin, polysulfone resin, polyethersulfone resin, polyphenylene ether resin, polycarbonate resin, polyetheretherketone resin, and polyester resin; 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; and leveling agents such as silicone-based leveling agents and acrylic polymer-based leveling agents. Examples of additives include: thickeners such as bentonite and montmorillonite; defoamers such as silicone-based defoamers, acrylic-based defoamers, fluorine-based defoamers, and vinyl resin-based defoamers; ultraviolet absorbers such as benzotriazole-based ultraviolet absorbers; adhesion improvers such as urea silane; adhesion improvers such as triazole-based adhesion improvers, tetrazole-based adhesion improvers, and triazine-based adhesion improvers; antioxidants such as hindered phenol-based antioxidants and hindered amine-based antioxidants; fluorescent whitening agents such as stilbene derivatives; surfactants such as fluorine-based surfactants and silicone-based surfactants; and flame retardants such as phosphorus-based flame retardants (e.g., phosphate ester compounds, phosphazene compounds, phosphinic acid compounds, red phosphorus), nitrogen-based flame retardants (e.g., melamine sulfate), halogen-based flame retardants, and inorganic flame retardants (e.g., antimony trioxide). 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 those skilled in the art.

[0119] <(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 tetrahydropyran, tetrahydrofuran, 1,4-dioxane, diethyl ether, diisopropyl ether, dibutyl ether, and diphenyl ether; alcohol solvents such as methanol, ethanol, propanol, butanol, and ethylene glycol; 2-ethoxyethyl acetate, propylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, ethyl diglycol acetate, γ-butyrolactone, and methyl methoxypropionate. Examples include ether ester solvents such as: methyl lactate, ethyl lactate, methyl 2-hydroxyisobutyrate, etc.; ether alcohol solvents such as 2-methoxypropanol, 2-methoxyethanol, 2-ethoxyethanol, propylene glycol monomethyl ether, diethylene glycol monobutyl ether (butyl carbitol), etc.; amide solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, etc.; sulfoxide solvents such as dimethyl sulfoxide, etc.; nitrile solvents such as acetonitrile, propionitrile, etc.; aliphatic hydrocarbon solvents such as hexane, cyclopentane, cyclohexane, methylcyclohexane, etc.; aromatic hydrocarbon solvents such as benzene, toluene, xylene, ethylbenzene, trimethylbenzene, etc. (G) Organic solvents may be used individually or in combination of two or more in any ratio.

[0120] <Method for producing resin compositions> The resin composition of the present invention can be produced, for example, by adding (A) epoxy resin, (B) inorganic filler, (C) polyimide resin (pre-imidized), optionally (D) curing agent, optionally (E) curing accelerator, optionally (F) other additives, and optionally (G) organic solvent in any order and / or partially or entirely simultaneously to any reaction vessel and mixing. The temperature can be set appropriately during the process of adding and mixing each component, and heating and / or cooling may be performed temporarily or throughout the process. Stirring or shaking may also be performed during the process of adding and mixing each component. The resin composition may also be stirred using a stirring device such as a mixer, for example, during or after adding and mixing, to ensure uniform dispersion.

[0121] <Properties of resin compositions> The resin composition of the present invention comprises (A) epoxy resin, (B) inorganic filler, and (C) polyimide resin. Since component (A) contains (A-1) siloxane skeleton-containing epoxy resin, even with a low concentration of inorganic filler (B) of 40% by mass or less, tackiness can be kept low, and a cured product with excellent flexibility and excellent insulation reliability can be obtained.

[0122] Since the cured product of the resin composition of the present invention has excellent flexibility, for example, as shown in Test Example 1 below, when an MIT bending resistance test is performed on a layered cured product of the resin composition with a thickness of 40 μm, a width of 15 mm, and a length of 110 mm, with a load of 2.5 N, a bending angle of 90 degrees, a bending speed of 175 times / min, and a bending radius of 1.0 mm in accordance with JIS C-5016, the number of bending cycles it can withstand is preferably 3,000 or more, more preferably 5,000 or more, even more preferably 7,000 or more, and particularly preferably 8,000 or more.

[0123] The cured product of the resin composition of the present invention exhibits excellent insulation reliability. For example, the insulation resistance value of the insulating layer of the evaluation substrate measured by the method of Test Example 3 described below is preferably 1.00 × 10⁻⁶. 7 Ω or greater, more preferably 1.00 × 10⁻¹⁰ 8 Ω or greater, more preferably 1.00 × 10⁻¹⁰9 Ω or greater, particularly preferably 1.00 × 10⁻⁶ 10 It could be Ω or higher.

[0124] The resin composition of the present invention can keep tackiness low, for example, as shown in Test Example 2 below, with a glass probe diameter of 5 mm and a load of 1 kgf / cm², 2 The tack force measured under the conditions of a contact speed of 0.5 mm / sec, a tensile speed of 0.5 mm / sec, a holding time of 10 seconds, and a temperature of 80°C is preferably 1.8 N or less, more preferably 1.6 N or less, even more preferably 1.4 N or less, and particularly preferably 1.2 N or less.

[0125] <Uses of resin compositions> The resin composition of the present invention can be used in a wide range of applications, including insulating materials for printed circuit boards and multilayer flexible substrates, solder resists, underfill materials, die bonding materials, semiconductor encapsulants, hole-filling resins, and component-embedding resins. Printed circuit boards and multilayer flexible substrates can be manufactured, for example, using sheet-like laminated materials such as resin sheets and prepregs.

[0126] <Resin sheet> The resin sheet of the present invention includes a support and a resin composition layer formed of the resin composition of the present invention provided on the support.

[0127] The thickness of the resin composition layer is preferably 200 μm or less, more preferably 150 μm or less, even more preferably 100 μm or less, and particularly preferably 70 μm or less. The lower limit of the thickness of the resin composition layer is not particularly limited, but can usually be 1 μm or more, 1.5 μm or more, 2 μm or more, etc.

[0128] 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.

[0129] 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.

[0130] 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.

[0131] The support may have a matte finish, corona treatment, or antistatic treatment applied to the surface that bonds with the resin composition layer.

[0132] 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.

[0133] 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.

[0134] In one embodiment, the resin sheet may further include other layers as needed. Such other layers include, 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 for example, it is 1 μm to 40 μm. By laminating the protective film, the adhesion of dust and other debris and scratches to the surface of the resin composition layer can be suppressed.

[0135] Resin sheets can be manufactured by applying a resin varnish, either directly from the resin composition or prepared by dissolving the resin composition in an organic solvent, onto a support using a die coater or the like, and then drying it to form a resin composition layer.

[0136] Examples of organic solvents that can be used when coating onto a support include those similar to those listed in the description of organic solvents as components of resin compositions. Organic solvents may be used individually or in combination of two or more.

[0137] 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.

[0138] The resin sheet can be stored by rolling it up. If the resin sheet has a protective film, it can be used after removing the protective film.

[0139] <Laminated sheet> A laminated sheet is a sheet manufactured by laminating and curing multiple resin composition layers. The laminated sheet contains multiple insulating layers as cured products of the resin composition layers. Typically, the number of resin composition layers laminated to manufacture a laminated sheet corresponds to the number of insulating layers contained in the laminated sheet. The specific number of insulating layers per laminated sheet is usually 2 or more, preferably 3 or more, particularly preferably 5 or more, preferably 20 or less, more preferably 15 or less, and particularly preferably 10 or less.

[0140] The laminated sheet may be a sheet that is used by folding it so that one side faces the other. The minimum bending radius of the laminated sheet is not particularly limited, but is preferably 0.1 mm or more, more preferably 0.2 mm or more, even more preferably 0.3 mm or more, preferably 5 mm or less, more preferably 4 mm or less, and particularly preferably 3 mm or less.

[0141] Holes may be formed in each insulating layer within the laminated sheet. These holes can function as via holes or through holes in a multilayer flexible substrate.

[0142] The laminated sheet may include additional optional elements in addition to the insulating layer. For example, the laminated sheet may include a conductive layer as an optional element. The conductive layer is usually partially formed on the surface of the insulating layer or between the insulating layers. This conductive layer typically functions as wiring in a multilayer flexible substrate.

[0143] The conductive material used in 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 material may be a single metal or an alloy. Examples of alloys include alloys of two or more metals selected from the above group (e.g., nickel-chromium alloys, copper-nickel alloys, and copper-titanium alloys). Among these, from the viewpoint of versatility in conductive layer formation, cost, and ease of patterning, single metals such as chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver, or copper; and alloys such as nickel-chromium alloys, copper-nickel alloys, and copper-titanium alloys are preferred. Among these, single metals of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver, or copper; and nickel-chromium alloys are more preferred, and single metal copper is even more preferred.

[0144] The conductive layer may be a single-layer structure, or it may be a multi-layer structure containing two or more single-metal or alloy layers made of different types of metals or alloys. 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.

[0145] The conductor layer may be patterned to function as wiring.

[0146] The thickness of the conductor layer depends on the design of the multilayer flexible substrate, but is preferably 3 μm to 35 μm, more preferably 5 μm to 30 μm, even more preferably 10 μm to 20 μm, and particularly preferably 15 μm to 20 μm.

[0147] The thickness of the laminated sheet is preferably 100 μm or more, more preferably 150 μm or more, particularly preferably 200 μm or more, preferably 2,000 μm or less, more preferably 1,000 μm or less, and particularly preferably 500 μm or less.

[0148] <Method for manufacturing laminated sheets> A laminated sheet can be manufactured by a manufacturing method that includes (a) a step of preparing a resin sheet, and (b) a step of laminating and curing multiple resin composition layers using the resin sheet. The order of lamination and curing of the resin composition layers is arbitrary, as long as the desired laminated sheet is obtained. Depending on the components contained in the resin composition, for example, multiple resin composition layers may be laminated and then cured all at once. Alternatively, for example, the laminated resin composition layers may be cured each time another resin composition layer is laminated onto a given resin composition layer.

[0149] A preferred embodiment of step (b) is described below. In the embodiment described below, for the purpose of distinction, the resin composition layers are appropriately numbered as "first resin composition layer" and "second resin composition layer," and the insulating layers obtained by curing these resin composition layers are also numbered as "first insulating layer" and "second insulating layer" in the same manner as the resin composition layers.

[0150] In one preferred embodiment, step (b) is: (II) A step of curing the first resin composition layer to form the first insulating layer, (VI) A step of laminating a second resin composition layer onto the first insulating layer, (VII) A step of curing the second resin composition layer to form a second insulating layer, This includes. Also, step (b) may be performed as needed. (I) A step of laminating a first resin composition layer onto a sheet support substrate, (III) The process of drilling holes in the first insulating layer, (IV) A step of roughening the first insulating layer, (V) Step of forming a conductive layer on the first insulating layer. The process may include any of the following optional steps. Each step will be explained below.

[0151] Step (I) is a step of laminating a first resin composition layer onto the sheet support substrate before step (II). The sheet support substrate is a peelable material, and for example, a plate-shaped, sheet-shaped, or film-shaped material can be used.

[0152] Lamination of the sheet support substrate and the first resin composition layer may be carried out by a vacuum lamination method. In the vacuum lamination method, the heat-pressing 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-pressing 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-pressing time is preferably in the range of 20 seconds to 400 seconds, more preferably in the range of 30 seconds to 300 seconds. Lamination is preferably carried out under reduced pressure conditions of 26.7 hPa or less.

[0153] 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.

[0154] When using a resin sheet, lamination of the sheet support substrate and the first resin composition layer can be performed, for example, by pressing the resin sheet from the support side and heat-pressing the first resin composition layer of the resin sheet onto the sheet support substrate. Examples of a member used to heat-press the resin sheet onto the sheet support substrate (hereinafter sometimes 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). Rather than directly pressing the heat-pressing member onto the resin sheet, it is preferable to press via an elastic material such as heat-resistant rubber so that the first resin composition layer can adequately follow the surface irregularities of the sheet support substrate.

[0155] After lamination, the first resin composition layer may be smoothed by pressing it with a heat-sealing member under normal pressure (atmospheric pressure). For example, if a resin sheet is used, the first resin composition layer of the resin sheet can be smoothed by pressing the resin sheet from the support side with a heat-sealing member. The pressing conditions for the smoothing treatment can be the same as the heat-sealing conditions for lamination. The smoothing treatment can be performed using a commercially available laminator. Lamination and smoothing may be performed continuously using the commercially available vacuum laminator described above.

[0156] Step (II) is a step of curing the first resin composition layer to form the first insulating layer. The curing conditions for the first resin composition layer are not particularly limited, and any conditions used when forming the insulating layer of a printed circuit board can be arbitrarily applied. The first resin composition layer can be cured, for example, by heat curing.

[0157] Typically, the specific heat curing conditions vary depending on the type of resin composition. For example, 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 is preferably 5 minutes to 120 minutes, more preferably 10 minutes to 110 minutes, and even more preferably 20 minutes to 100 minutes.

[0158] Prior to thermal curing the first resin composition layer, the first resin composition layer may be preheated at a temperature lower than the curing temperature. For example, prior to thermal curing the first resin composition layer, the first resin composition layer may be preheated at a temperature of 50°C or higher but less than 120°C (preferably 60°C or higher but less than 115°C, more preferably 70°C or higher but less than 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).

[0159] Step (III) is a step of drilling holes in the first insulating layer. This step (III) can form holes such as via holes and through holes in the first insulating layer. Drilling may be performed using, for example, a drill, laser, or plasma, depending on the composition of the resin composition. The dimensions and shape of the holes may be set as appropriate according to the design of the multilayer flexible substrate.

[0160] Step (IV) is a process of roughening the first insulating layer. Typically, smear removal is also performed in this step (IV). Therefore, the roughening process is sometimes called desmearing. An example of a roughening process is a method in which swelling treatment with a swelling solution, roughening treatment with an oxidizing agent, and neutralization treatment with a neutralizing solution are performed in that order.

[0161] The swelling solution is not particularly limited, but examples include alkaline aqueous solutions such as sodium hydroxide aqueous solution and potassium hydroxide aqueous solution. 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 can be carried out, for example, by immersing the cured body in a swelling solution at 30 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 to 80°C for 5 to 15 minutes.

[0162] The oxidizing agent is not particularly limited, but examples include alkaline permanganate solutions obtained by dissolving permanganate in an aqueous sodium hydroxide solution or an aqueous potassium hydroxide solution. 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 P," "Concentrate Compact CP," and "Dosing Solution Securigans P" manufactured by Attec Japan. The roughening treatment with an oxidizing agent can be carried out by immersing the hardened body in an oxidizing agent solution heated to 60°C to 80°C for 10 to 30 minutes.

[0163] Furthermore, an acidic aqueous solution is used as the neutralizing solution. A commercially available example is "Reduction Solution Securigant P" manufactured by Attec Japan. The treatment with the neutralizing solution can be carried out by immersing the hardened body in a neutralizing solution at 30°C to 80°C for 5 to 30 minutes. From the standpoint of workability, it is preferable to immerse the hardened body in a neutralizing solution at 40°C to 70°C for 5 to 20 minutes.

[0164] The arithmetic mean roughness (Ra) of the surface of the first insulating layer after roughening treatment is preferably 400 nm or less, more preferably 300 nm or less, and even more preferably 200 nm or less. The lower limit is not particularly limited, but may be 30 nm or more, 40 nm or more, or 50 nm or more.

[0165] Step (V) is a step of forming a conductor layer on the first insulating layer, if necessary. Examples of methods for forming the conductor layer include plating, sputtering, and vapor deposition, with plating being preferred. A suitable example is a method of plating the surface of the first insulating layer by an appropriate method such as a semi-additive method or a fully additive method to form a conductor layer having a desired wiring pattern. Among these, the semi-additive method is preferred from the viewpoint of ease of manufacture.

[0166] The following is an example of forming a conductor layer using a semi-additive method. First, a plating seed layer is formed on the surface of the first 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 processes to form a conductor layer having the desired wiring pattern.

[0167] In step (II), the first insulating layer is obtained, and after performing steps (III), (IV), and (V) as necessary, step (VI) is performed. Step (VI) is the process of laminating the second resin composition layer onto the first insulating layer. The lamination of the first insulating layer and the second resin composition layer can be carried out in the same way as the lamination of the sheet support substrate and the first resin composition layer in step (I).

[0168] However, if a resin sheet is used to form the first resin composition layer, the support of the resin sheet is removed before step (VI). The removal of the support may be performed between step (I) and step (II), between step (II) and step (III), between step (III) and step (IV), or between step (IV) and step (V).

[0169] After step (VI), step (VII) is performed. Step (VII) is a step in which the second resin composition layer is cured to form the second insulating layer. The curing of the second resin composition layer can be carried out in the same way as curing the first resin composition layer in step (II). This makes it possible to obtain a laminated sheet containing multiple insulating layers, namely the first insulating layer and the second insulating layer.

[0170] Furthermore, in the method according to the above embodiment, the following steps may be taken as needed: (VIII) a step of drilling holes in the second insulating layer, (IX) a step of roughening the second insulating layer, and (X) a step of forming a conductor layer on the second insulating layer. Drilling holes in the second insulating layer in step (VIII) can be done in the same way as drilling holes in the first insulating layer in step (III). Also, roughening the second insulating layer in step (IX) can be done in the same way as roughening the first insulating layer in step (IV). In addition, forming a conductor layer on the second insulating layer in step (X) can be done in the same way as forming a conductor layer on the first insulating layer in step (V).

[0171] In the above embodiment, an embodiment was described in which a laminated sheet is manufactured by laminating and curing two resin composition layers, a first resin composition layer and a second resin composition layer. However, a laminated sheet may also be manufactured by laminating and curing three or more resin composition layers. For example, in the method according to the above embodiment, a laminated sheet may be manufactured by repeatedly performing the lamination and curing of resin composition layers by steps (VI) to (VII), and, if necessary, drilling holes in the insulating layer, roughening the insulating layer, and forming a conductor layer on the insulating layer by steps (VIII) to (X). This will result in a laminated sheet containing three or more insulating layers.

[0172] Furthermore, the method according to the above embodiment may include any steps other than those described above. For example, if step (I) is performed, a step of removing the sheet support substrate may be performed.

[0173] <Multilayer Flexible Circuit Board> A multilayer flexible substrate includes a laminated sheet. The multilayer flexible substrate may include only the laminated sheet, or it may include any other components in combination with the laminated sheet. Examples of such components include electronic components and coverlay films.

[0174] A multilayer flexible substrate can be manufactured by a manufacturing method that includes the method for manufacturing the laminated sheet described above. Therefore, a multilayer flexible substrate can be manufactured by a manufacturing method that includes (a) a step of preparing a resin sheet, and (b) a step of laminating and curing multiple resin composition layers using the resin sheet.

[0175] A method for manufacturing a multilayer flexible substrate may include any additional steps in combination with the above-mentioned steps. For example, a method for manufacturing a multilayer flexible substrate equipped with electronic components may include a step of bonding the electronic components to a laminated sheet. The bonding conditions between the laminated sheet and the electronic components can be any conditions that allow a conductive connection between the terminal electrodes of the electronic components and the conductor layer provided on the laminated sheet as wiring. Also, for example, a method for manufacturing a multilayer flexible substrate equipped with a coverlay film may include a step of laminating the laminated sheet and the coverlay film.

[0176] The aforementioned multilayer flexible substrate can typically be used by folding it so that one side of the laminated sheets it contains faces the other. For example, the multilayer flexible substrate can be folded to reduce its size and housed in the housing of a semiconductor device. Alternatively, for example, the multilayer flexible substrate can be provided in a semiconductor device that has a bendable movable part.

[0177] <Semiconductor device> The semiconductor device comprises the multilayer flexible substrate described above. The semiconductor device comprises, for example, a multilayer flexible substrate and a semiconductor chip mounted on the multilayer flexible substrate. In many semiconductor devices, the multilayer flexible substrate can be housed in the housing of the semiconductor device by folding it so that one side of the laminated sheets contained in the multilayer flexible substrate faces the other.

[0178] 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).

[0179] The aforementioned semiconductor device can be manufactured by a manufacturing method that includes, for example, the steps of: preparing a multilayer flexible substrate; bending the multilayer flexible substrate so that one side of the laminated sheet faces the other; and housing the bent multilayer flexible substrate in a housing. [Examples]

[0180] 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. Furthermore, unless otherwise specified, the operations described below were carried out in an environment of normal temperature and pressure (25°C, 1 atm).

[0181] <Synthesis Example 1: Synthesis of Polyimide Resin 1> In a reaction vessel, 50 g of G-3000 (bifunctional hydroxyl-terminated polybutadiene, number average molecular weight = 5,047 (GPC method), hydroxyl group equivalent = 1,798 g / eq., solids content 100% by mass: manufactured by Nippon Soda Co., Ltd.), 23.5 g of Ipsol 150 (aromatic hydrocarbon mixed solvent: manufactured by Idemitsu Petrochemical Co., Ltd.) and 0.005 g of dibutyltin laurate were mixed and dissolved uniformly. Once homogeneous, the temperature was raised to 50°C, and while stirring, 4.8 g of toluene-2,4-diisocyanate (isocyanate group equivalent = 87.08 g / eq.) was added and the reaction was carried out for approximately 3 hours. Next, the reaction mixture was cooled to room temperature, and then 8.96 g of benzophenone tetracarboxylic dianhydride (acid anhydride equivalent = 161.1 g / eq.), 0.07 g of triethylenediamine, and 40.4 g of ethyl diglycol acetate (manufactured by Daicel Corporation) were added. The mixture was heated to 130°C while stirring and the reaction was carried out for approximately 4 hours. FTIR reading was 2250 cm⁻¹. -1 The disappearance of the NCO peak was confirmed. The disappearance of the NCO peak was considered the endpoint of the reaction, and the reactants were cooled to room temperature and filtered through a 100-mesh filter cloth to obtain polyimide resin 1 having an imide skeleton, a urethane skeleton, and a butadiene skeleton. Viscosity: 7.5Pa s (25℃, E-type viscometer) Acid value: 16.9 mg KOH / g Solid content: 50% by mass Number average molecular weight: 13,723 Glass transition temperature: -10℃ Polybutadiene structural content: 50 / (50+4.8+8.96)×100 = 78.4% by mass

[0182] <Synthesis Example 2: Synthesis of Polyimide Resin 2> In a 500 ml separable flask equipped with a nitrogen inlet tube and a stirrer, 9.13 g (30 mmol) of 5-amino-1,1'-biphenyl-2-yl 4-aminobenzoate, 15.61 g (30 mmol) of 4,4'-(4,4'-isopropylidene diphenoxy)bisphthalic acid dianhydride, 94.64 g of N-methyl-2-pyrrolidone, 0.47 g (6 mmol) of pyridine, and 10 g of toluene were added. Under a nitrogen atmosphere, the imidation reaction was carried out at 180°C for 4 hours, with the toluene being removed from the system during the process, to obtain a polyimide solution containing polyimide resin 2 (20% by mass of non-volatile content). No precipitation of the synthesized polyimide resin 2 was observed in the polyimide solution. The weight-average molecular weight of polyimide resin 2 was 45,000.

[0183] <Synthesis Example 3: Synthesis of Polyimide Resin 3> In a reaction vessel equipped with a stirrer, water divider, thermometer, and nitrogen gas inlet tube, 65.0 g of aromatic tetracarboxylic dianhydride (SABIC Japan's "BisDA-1000," 4,4'-(4,4'-isopropylidene diphenoxy)bisphthalic acid dianhydride), 266.5 g of cyclohexanone, and 44.4 g of methylcyclohexane were charged, and the solution was heated to 60°C. Then, 43.7 g of dimeramine (Croda Japan's "PRIAMINE 1075") and 5.4 g of 1,3-bis(aminomethyl)cyclohexane were added dropwise, and the imidation reaction was carried out at 140°C for 1 hour. This yielded a polyimide solution containing polyimide resin 3 (non-volatile content 30% by mass). The weight-average molecular weight of polyimide resin 3 was 25,000.

[0184] <Synthesis Example 4: Synthesis of Polyimide Resin 4> A 500 mL separable flask was prepared, equipped with a moisture meter connected to a reflux condenser, a nitrogen inlet tube, and a stirrer. 20.3 g of 4,4'-oxydiphthalic anhydride (ODPA), 200 g of γ-butyrolactone, 20 g of toluene, and 29.6 g of 5-(4-aminophenoxy)-3-[4-(4-aminophenoxy)phenyl]-1,1,3-trimethylindan were added to this flask, and the reaction was carried out by stirring at 45°C for 2 hours under a nitrogen stream. Next, the reaction solution was heated and maintained at approximately 160°C, while azeotropically removing the condensed water with toluene under a nitrogen stream. It was confirmed that the predetermined amount of water had accumulated in the moisture meter and that no further water leakage was observed. After confirmation, the reaction solution was further heated and stirred at 200°C for 1 hour. Subsequently, the mixture was cooled to obtain a polyimide solution (20% by mass of non-volatile content) containing a polyimide resin 4 having a 1,1,3-trimethylindan skeleton. The obtained polyimide resin 4 had repeating units represented by the following formula (X1) and the following formula (X2). The weight-average molecular weight of the polyimide resin 4 was 12,000.

[0185] [ka]

[0186] [ka]

[0187] <Example 1: Preparation of Resin Composition 1> Five parts of bixylenol-type epoxy resin (Mitsubishi Chemical's "YX4000HK", epoxy equivalent approximately 185 g / eq.), five parts of naphthalene-type epoxy resin (Nippon Steel & Sumitomo Metal Chemical's "ESN475V", epoxy equivalent approximately 332 g / eq.), ten parts of bisphenol AF-type epoxy resin (Mitsubishi Chemical's "YL7760", epoxy equivalent approximately 238 g / eq.), two parts of cyclohexane-type epoxy resin (Mitsubishi Chemical's "ZX1658GS", epoxy equivalent approximately 135 g / eq.), and 40 parts of polyimide resin 1 (50% by mass of non-volatile components) obtained in Synthesis Example 1 were heated and dissolved in 10 parts of cyclohexanone with stirring. After cooling to room temperature, add the following: 4 parts of a triazine skeleton-containing cresol novolac curing agent (DIC Corporation's "LA3018-50P", hydroxyl group equivalent approximately 151 g / eq., 2-methoxypropanol solution with 50% non-volatile content), 6 parts of an active ester curing agent (DIC Corporation's "EXB-8000L-65M", active group equivalent approximately 220 g / eq., MEK solution with 65% by mass of non-volatile components), and spherical silica (Admatex Corporation's "SC2500SQ", average particle size 0.5 μm, specific surface area 11.2 m²). 2 Resin composition 1 was prepared by mixing 25 parts of silica (surface-treated with 1 part N-phenyl-3-aminopropyltrimethoxysilane (Shin-Etsu Chemical Co., Ltd., KBM573) per 100 parts of silica), 6 parts of siloxane skeleton-containing epoxy resin (Shin-Etsu Chemical Co., Ltd., "KR470", epoxy equivalent approximately 200 g / eq.), and 0.2 parts of amine-based curing accelerator (4-dimethylaminopyridine (DMAP)), dispersing them uniformly in a high-speed rotary mixer, and then filtering through a cartridge filter (ROKITECHNO, "SHP020").

[0188] <Example 2: Preparation of Resin Composition 2> Resin composition 2 was prepared by performing the same procedure as in Example 1, except that 100 parts of polyimide resin 2 (20% by mass of non-volatile components) obtained in Synthesis Example 2 were used instead of 40 parts of polyimide resin 1 (50% by mass of non-volatile components) obtained in Synthesis Example 1.

[0189] <Example 3: Preparation of Resin Composition 3> Resin composition 3 was prepared by performing the same procedure as in Example 1, except that 66.7 parts of polyimide resin 3 (30% by mass of non-volatile components) obtained in Synthesis Example 3 were used instead of 40 parts of polyimide resin 1 (50% by mass of non-volatile components) obtained in Synthesis Example 1.

[0190] <Example 4: Preparation of Resin Composition 4> Resin composition 4 was prepared by performing the same procedure as in Example 1, except that 100 parts of polyimide resin 4 (20% by mass of non-volatile components) obtained in Synthesis Example 4 were used instead of 40 parts of polyimide resin 1 (50% by mass of non-volatile components) obtained in Synthesis Example 1.

[0191] <Comparative Example 1: Preparation of Resin Composition 5> Resin composition 5 was prepared by performing the same procedure as in Example 1, except that 6 parts of siloxane skeleton-containing epoxy resin (Shin-Etsu Chemical Co., Ltd., "KR470", epoxy equivalent approximately 200 g / eq.) were not used.

[0192] <Comparative Example 2: Preparation of Resin Composition 6> Resin composition 6 was prepared by performing the same procedure as in Example 1, except that 66 parts of phenoxy resin (Mitsubishi Chemical Corporation's "YX7553BH30", 30% solids by mass) were used instead of 40 parts of polyimide resin 1 (50% by mass of non-volatile components) obtained in Synthesis Example 1.

[0193] <Test Example 1: Evaluation of Flexibility (MIT Folding Resistance)> The resin compositions of each example and comparative example were uniformly applied using a die coater to the release-treated surface of a PET film (38 μm thick) treated with an alkyd-based release agent, so that the thickness of the dried resin composition layer was 40 μm. The mixture was then dried at 80-120°C (average 100°C) for 6 minutes to obtain resin sheet 1.

[0194] The obtained resin sheet 1 was laminated onto a polyimide film (Yupi-Rex S, manufactured by Ube Industries, Ltd.) using a batch-type vacuum pressure laminator (MVLP-500, manufactured by Meiki Seisakusho Co., Ltd.) to obtain a resin sheet with a protective film. The lamination was performed by reducing the pressure to 13 hPa or less for 30 seconds, followed by pressing at 0.74 MPa at 120°C for 30 seconds. After that, the PET film was peeled off, and the resin composition was cured under curing conditions of 190°C for 90 minutes, and the polyimide film was peeled off to obtain a cured sample.

[0195] The obtained cured material samples were cut into test pieces measuring 15 mm in width and 110 mm in length. Using an MIT testing apparatus (MIT-DA folding fatigue tester, manufactured by Toyo Seiki Seisakusho Co., Ltd.), the number of folding cycles until fracture of the cured material was measured in accordance with JIS C-5016 under the following measurement conditions: load of 2.5 N, bending angle of 90 degrees, bending radius of 1.0 mm, and bending speed of 175 cycles / minute. Measurements were performed on 5 samples, and the average of the top 3 scores was calculated. A folding cycle of less than 8,000 was evaluated as "×", and a folding cycle of 8,000 or more was evaluated as "○".

[0196] <Test Example 2: Evaluation of Tackiness (Adhesion)> The protective film was peeled off from the resin sheet with protective film obtained in Test Example 1, and the resin composition layer was tested using a probe tack tester (TE-6002, manufactured by Tester Sangyo Co., Ltd.) with a 5 mm diameter glass probe and a load of 1 kgf / cm². 2 The tack force was measured at a contact speed of 0.5 mm / sec, a tensile speed of 0.5 mm / sec, a holding time of 10 seconds, and a temperature of 80°C. A tack force exceeding 1.6 N was evaluated as "×", and a tack force of 1.6 N or less was evaluated as "○".

[0197] <Test Example 3: Evaluation of Insulation Reliability> (1) Surface preparation of the inner layer circuit board As the inner layer circuit board, a glass cloth substrate epoxy resin double-sided copper-clad laminate (copper foil thickness 3 μm, substrate thickness 0.15 mm, Mitsubishi Gas Chemical Co., Ltd. "HL832NSF LCA", 255 × 340 mm size) was prepared, having circuit conductors (copper) formed with an L / S = 10 μm / 10 μm wiring pattern on both sides. Both sides of the inner layer circuit board were treated with an organic coating on the copper surface using MEC's ​​"FlatBOND-FT".

[0198] (2) Lamination of resin sheets The protective film was removed from the resin sheet with protective film obtained in Test Example 1, and the resin composition layer was laminated to both sides of the inner circuit board using a batch-type vacuum pressure laminator (Nikko Materials Co., Ltd., 2-stage build-up laminator, CVP700) so that the resin composition layer was in contact with the inner circuit board. Lamination was performed by reducing the pressure to 13 hPa or less for 30 seconds, and then pressing at 130°C and a pressure of 0.74 MPa for 45 seconds. Subsequently, a hot press was performed at 120°C and a pressure of 0.5 MPa for 75 seconds.

[0199] (3) Thermocuring of the resin composition layer The inner layer circuit board, laminated with a resin sheet, was placed in a 100°C oven for 30 minutes, then transferred to a 180°C oven for another 30 minutes to heat-cur it and form an insulating layer, after which the release PET was peeled off.

[0200] (4) Roughening treatment The inner layer circuit board, which had an insulating layer formed on it, underwent a desmear treatment as a roughening process. The desmear treatment performed was the wet desmear treatment described below. Wet desmear treatment: The substrate was immersed in a swelling solution (Atotec Japan's "Swelling Dip Securigant P," an aqueous solution of diethylene glycol monobutyl ether and sodium hydroxide) at 60°C for 5 minutes, then in an oxidizing agent solution (Atotec Japan's "Concentrate Compact CP," an aqueous solution of potassium permanganate at approximately 6% and sodium hydroxide at approximately 4%) at 80°C for 10 minutes, and finally in a neutralizing solution (Atotec Japan's "Reduction Solution Securigant P," an aqueous sulfuric acid solution) at 40°C for 5 minutes, after which it was dried at 80°C for 15 minutes. This was designated as "Roughened Substrate A."

[0201] (5) Formation of the conductive layer (5-1) Electroless plating To form a conductive layer on the roughened surface of the roughened substrate A described above, a plating process (copper plating process using chemicals manufactured by Attec Japan Co., Ltd.) including the following steps 1 to 6 was performed to form the conductive layer.

[0202] 1. Alkaline cleaning (cleaning and charge adjustment of the insulating layer surface) The surface of roughened substrate A was cleaned at 60°C for 5 minutes using Cleaning Cleaner Securiganth 902 (product name). 2. Soft etching (cleaning inside the via hall) The surface of roughened substrate A was treated with a sulfuric acid-acidified sodium peroxodisulfate aqueous solution at 30°C for 1 minute. 3. Pre-dip (adjustment of the surface charge of the insulating layer for Pd deposition) The surface of roughened substrate A was treated with Pre. Dip Neoganth B (trade name) at room temperature for 1 minute. 4. Activator application (application of Pd to the surface of the insulating layer) The surface of roughened substrate A was treated with Activator Neoganth 834 (trade name) at 35°C for 5 minutes. 5. Reduction (Reduction of Pd deposited on the insulating layer) The surface of roughened substrate A was treated with a mixture of Reducer Neoganth WA (trade name) and Reducer Acceralator 810 mod. (trade name) at 30°C for 5 minutes. 6. Electroless copper plating (depositing Cu onto the surface of the insulating layer (Pd surface)) A mixture of Basic Solution Printganth MSK-DK (product name), Copper Solution Printganth MSK (product name), Stabilizer Printganth MSK-DK (product name), and Reducer Cu (product name) was used to treat the surface of roughened substrate A at 35°C for 20 minutes to form an electroless copper plating layer. The thickness of the formed electroless copper plating layer was 0.8 μm.

[0203] (5-2) Electroplating Next, an electrolytic copper plating process was performed using a chemical solution manufactured by Atotec Japan, under conditions that copper was filled into the via holes. Subsequently, a conductive layer with lands and conductive patterns was formed on the surface of the insulating layer with a thickness of 10 μm, using a 1 mm diameter land pattern connected to the underlying conductor and a 10 mm diameter circular conductive pattern not connected to the underlying conductor, as a resist pattern for etching. Next, an annealing treatment was performed at 200°C for 90 minutes. This substrate was designated as "Evaluation Substrate A".

[0204] (6) Evaluation of the insulation reliability of the insulating layer The 10mm diameter circular conductor side of evaluation board A was used as the positive electrode, and the grid circuit conductor (copper) side of the inner layer circuit board connected to the 1mm diameter land was used as the negative electrode. Using an accelerated lifetime testing system (ETAC "PM422"), the insulation resistance value was measured using an electrochemical migration tester (J-RAS "ECM-100") after 100 hours under the conditions of 110°C, 85% relative humidity, and 20V DC voltage. This measurement was performed six times, and the resistance value for all six test pieces was 1.00 × 10⁻⁶. 8 If it is Ω or greater, mark it with "○", even if there is only one, it is 1.00 × 10 8If the value is less than Ω, it is marked with "×", and the evaluation result and insulation resistance value are shown in the table below. The insulation resistance values ​​listed in Table 1 below are the lowest values ​​of the insulation resistance values ​​of the six test pieces.

[0205] The amount of non-volatile components used in the resin compositions of the examples and comparative examples, the measurement results of the test examples, and the evaluation results are shown in Table 1 below.

[0206] [Table 1]

[0207] It has been found that a resin composition comprising (A) epoxy resin, (B) inorganic filler, and (C) polyimide resin, wherein component (A) is a resin composition comprising (A-1) siloxane skeleton-containing epoxy resin, can be used to obtain a cured product that has low tackiness even when the content of (B) inorganic filler is low, such as 40% by mass or less, and that also has excellent flexibility and excellent insulation reliability.

Claims

1. A resin composition comprising (A) an epoxy resin, (B) an inorganic filler, and (C) a polyimide resin, The component (A) contains (A-1) a siloxane skeleton-containing epoxy resin, The component (A-1) is a cyclic siloxane skeleton-containing epoxy resin, The content of the component (A) is 10% by mass or more, relative to 100% by mass of the nonvolatile components in the resin composition; When the total amount of the component (A) is taken as 100% by mass, the content of the component (A-1) is 20% by mass or more, The content of the (B) component is 20% by mass or more and 40% by mass or less, when the total amount of nonvolatile components in the resin composition is 100% by mass, the component (C) is (1) a resin obtained by a reaction including imidization between a diamine compound and a tetracarboxylic acid anhydride, or (2) a resin obtained by a reaction including imidization between a diisocyanate compound and a tetracarboxylic acid anhydride, A resin composition, wherein the content of component (C) is 10% by mass or more, based on 100% by mass of nonvolatile components in the resin composition.

2. A resin composition as described in claim 1, wherein the tetracarboxylic acid anhydride includes a tetracarboxylic acid anhydride selected from an aliphatic tetracarboxylic acid dianhydride and a diphthalic acid dianhydride.

3. The diamine compound includes a diamine compound selected from an aliphatic diamine compound and a dianiline compound, The resin composition according to claim 1, wherein the diisocyanate compound is selected from the group consisting of an aliphatic diisocyanate compound, a bisisocyanatobenzene compound, and a polyurethane having isocyanato groups at both ends.

4. The tetracarboxylic acid anhydride includes a tetracarboxylic acid anhydride selected from aliphatic tetracarboxylic acid dianhydrides and diphthalic acid dianhydride containing an oxygen atom as a backbone atom, the diamine compound includes a diamine compound selected from an aliphatic diamine compound and a dianiline compound; The resin composition according to claim 1, wherein the diisocyanate compound is selected from the group consisting of an aliphatic diisocyanate compound, a bisisocyanatobenzene compound, and a polyurethane having isocyanato groups at both ends.

5. The diamine compound includes an aliphatic diamine compound, the diisocyanate compound is selected from an aliphatic diisocyanate compound and a polyurethane having isocyanato groups at both ends obtained by a urethanization reaction of an aliphatic diisocyanate compound with a polymer having hydroxy groups at both ends, The resin composition according to claim 3.

6. The component (A-1) is represented by the formula (A1): 【Chemical 1】 6. The resin composition according to any one of claims 1 to 5, which is a compound represented by the formula: (wherein R 1 s each independently represent an epoxyalkyl group; R 2 s each independently represent a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, or a substituted or unsubstituted aryl group; R 3 and R 4 each independently represent a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, or a substituted or unsubstituted aryl group, or R 3 and R 4 together represent one -O- and bond to each other to form a cyclic siloxane skeleton; and s represents an integer of 1 or greater).

7. A resin composition described in any one of claims 1 to 6, wherein the molecular weight of component (A-1) is 800 or less.

8. The resin composition according to claim 1, wherein the epoxy equivalent of component (A-1) is 150 g / eq. to 250 g / eq.

9. A resin composition described in any one of claims 1 to 8, wherein the content of component (A-1) is 5 mass% or more when the non-volatile components in the resin composition are 100 mass%.

10. A resin composition described in any one of claims 1 to 9, wherein the content of component (A-1) is 10 mass% or less when the non-volatile components in the resin composition are 100 mass%.

11. A resin composition described in any one of claims 1 to 10, wherein the average particle size of component (B) is 0.005 μm or more and 1 μm or less.

12. A resin composition described in any one of claims 1 to 11, wherein component (B) is silica.

13. A resin composition described in any one of claims 1 to 12, wherein the weight average molecular weight of component (C) is 1,000 or more and 100,000 or less.

14. A resin composition described in any one of claims 1 to 13, wherein the content of component (C) is 20 mass% or more when the non-volatile components in the resin composition are 100 mass%.

15. A resin composition described in any one of claims 1 to 14, wherein the content of component (C) is 30 mass% or less when the non-volatile components in the resin composition are 100 mass%.

16. A resin composition described in any one of claims 1 to 15, further comprising (D) a curing agent.

17. The resin composition described in claim 16, wherein component (D) includes a curing agent selected from a phenol-based curing agent, a naphthol-based curing agent, an active ester-based curing agent, a benzoxazine-based curing agent, a cyanate ester-based curing agent, and a carbodiimide-based curing agent.

18. A resin composition as described in claim 16, wherein component (D) includes an active ester-based curing agent.

19. A resin resin composition described in any one of claims 1 to 18, which is for forming an insulating layer of a multilayer flexible substrate.

20. A cured product of the resin composition described in any one of claims 1 to 19.

21. A resin sheet comprising a support and a resin composition layer formed on the support from the resin composition described in any one of claims 1 to 19.

22. A multilayer flexible substrate comprising an insulating layer formed by curing the resin composition described in any one of claims 1 to 19.

23. A semiconductor device comprising the multilayer flexible substrate described in claim 22.

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