Block copolymer, resin composition, cured product, resin film, prepreg, laminate, and material for electronic circuit substrate

Abstract

The present invention relates to a block copolymer, a resin composition, a cured product, a resin film, a prepreg, a laminate, and a material for an electronic circuit substrate, and aims to provide a block copolymer which makes it possible to obtain a cured product having a low dielectric constant, a low dielectric loss tangent, and excellent strength characteristics. A block copolymer having a polymer block (A) mainly composed of a vinyl aromatic monomer unit, and a polymer block (B) mainly composed of a conjugated diene monomer unit and / or a polymer block (C) composed of a vinyl aromatic monomer unit and a conjugated diene monomer unit, which satisfies the following conditions (i) to (ii). <Condition (i)> The weight average molecular weight of the above block copolymer is 35,000 or less. <Condition (ii)> The content of the vinyl aromatic monomer unit in the above block copolymer is 55% by mass or more and 95% by mass or less.

Description

Technical Field

[0001] This invention relates to block copolymers, resin compositions, cured products, resin films, prepregs, laminates, and materials for electronic circuit boards. Background Technology

[0002] In recent years, with the significant advancement of information network technology and the expansion of services utilizing information networks, there is a growing demand for electronic devices to have larger information capacity and higher processing speeds.

[0003] To meet these requirements, materials with low dielectric loss are needed for various substrate materials, such as printed circuit boards or flexible substrates.

[0004] In the past, in order to obtain materials with low dielectric loss, various materials, such as resin cured products with epoxy resin and other thermosetting resins or polyphenylene ether resins as the main components, which have low dielectric constant and / or low dielectric loss tangent and excellent mechanical properties such as strength, have been studied and disclosed.

[0005] However, the existing publicly available materials have room for improvement from the viewpoint of low dielectric constant and low dielectric loss tangent, and when used on printed circuit boards, they have limitations in terms of information capacity and processing speed.

[0006] In order to improve this problem, various rubber components have been proposed as modifiers for the aforementioned thermosetting or thermoplastic resins.

[0007] For example, in Patent Document 1, as a modifier for reducing the dielectric loss tangent and the dielectric constant of polyphenylene ether resin, at least one elastomer selected from the group consisting of block copolymers of vinyl aromatic compounds and olefinic olefin compounds and their hydrides, and homopolymers of vinyl aromatic compounds are disclosed.

[0008] In addition, in Patent Document 2, a styrene-based elastomer is disclosed as a modifier for reducing the dielectric loss tangent and the dielectric constant of epoxy resin.

[0009] Existing technical documents

[0010] Patent documents

[0011] Patent Document 1: Japanese Patent Application Publication No. 2021-147486

[0012] Patent Document 2: Japanese Patent Application Publication No. 2020-15861 Summary of the Invention

[0013] The problem that the invention aims to solve

[0014] However, for resin compositions using the modifiers disclosed in Patent Documents 1 and 2, the reduction of dielectric constant and the reduction of dielectric loss tangent are not sufficient, and there is a problem that the strength is reduced due to the addition of the modifier and sufficient strength cannot be obtained.

[0015] Therefore, the object of the present invention is to provide a block copolymer and a resin composition containing the above-mentioned block copolymer, wherein the block copolymer can produce a cured product with low dielectric constant, low dielectric loss tangent, and excellent strength properties.

[0016] Methods for solving problems

[0017] In order to solve the problems of the prior art, the inventors conducted in-depth research and found that the cured resin composition containing a block copolymer with a specified structure has a low dielectric constant and a low dielectric loss tangent, as well as excellent strength characteristics, thereby completing the present invention.

[0018] That is, the present invention is as follows. [1]

[0020] A block copolymer having:

[0021] Polymer blocks (A) primarily composed of vinyl aromatic monomer units; and

[0022] Polymer blocks (B) mainly composed of conjugated diene monomer units and / or polymer blocks (C) composed of vinyl aromatic monomer units and conjugated diene monomer units,

[0023] The block copolymer satisfies the following conditions (i) to (ii).

[0024] <Condition(i)>

[0025] The weight-average molecular weight of the above block copolymers is below 35,000.

[0026] <Condition(ii)>

[0027] The content of vinyl aromatic monomer units in the above block copolymer is more than 55% by mass and less than 95% by mass. [2]

[0029] The block copolymers described above [1] also satisfy the following condition (iii).

[0030] <Condition (iii)>

[0031] The polymer block (B) and / or the polymer block (C) described above contain units (a) derived from 1,2-bonding and / or 3,4-bonding and units (b) derived from 1,4-bonding. When the total content of the polymer block (B) and / or the polymer block (C) described above is set to 100%, the content of the units (a) derived from 1,2-bonding and / or 3,4-bonding is 80% or less. [3]

[0033] A resin composition comprising:

[0034] Component (I): the block copolymer described in [1] or [2] above; and

[0035] Select at least one component from the group consisting of components (II) to (IV) below.

[0036] Component (II): Free radical initiator

[0037] Component (III): Polar resin (excluding component (I))

[0038] Component (IV): Hardener (excluding component (II)) [4]

[0040] The resin composition as described above [3], wherein the above component (III) is at least one selected from the group consisting of epoxy resin, polyimide resin, polyphenylene ether resin, liquid crystal polyester resin and fluorine resin. [5]

[0042] A cured product comprising the block copolymer described in [1] or [2] above. [6]

[0044] A cured product, which is a cured product of the resin composition described in [3] or [4] above. [7]

[0046] A resin film comprising the resin composition described in [3] or [4] above. [8]

[0048] A prepreg, which is a composite of a substrate and the resin composition described in [3] or [4] above. [9]

[0050] The prepreg described above [8], wherein the substrate is glass cloth.

[10]

[0052] A laminate having the resin film and metal foil described above[7].

[11]

[0054] A laminate having a cured prepreg as described in [8] or [9] above and a metal foil.

[12]

[0056] A material for electronic circuit boards comprising the cured material described above [6].

[0057] The effects of the invention

[0058] According to the present invention, a block copolymer and a resin composition containing the block copolymer can be provided, wherein the block copolymer can produce a cured product with low dielectric constant, low dielectric loss tangent, and excellent strength properties. Detailed Implementation

[0059] The specific embodiments of the present invention (hereinafter referred to as "this embodiment") will be described in detail below.

[0060] It should be noted that the following embodiments are illustrative of the present invention and are not intended to limit the present invention to the following content. The present invention can be implemented in various modifications within the scope of its essential points.

[0061] [Block copolymer]

[0062] The block copolymer of this embodiment has: a polymer block (A) mainly composed of vinyl aromatic monomer units (hereinafter sometimes referred to as polymer block (A)); a polymer block (B) mainly composed of conjugated diene monomer units (hereinafter sometimes referred to as polymer block (B)) and / or a polymer block (C) composed of vinyl aromatic monomer units and conjugated diene monomer units (hereinafter sometimes referred to as polymer block (C)).

[0063] The block copolymer of this embodiment satisfies the following conditions (i) to (ii).

[0064] <Condition(i)>

[0065] The weight-average molecular weight of the above block copolymers is below 35,000.

[0066] <Condition(ii)>

[0067] The content of vinyl aromatic monomer units in the above block copolymer is more than 55% by mass and less than 95% by mass.

[0068] According to the block copolymer of this embodiment, a cured resin composition with low dielectric constant, low dielectric loss tangent, and excellent strength properties can be obtained.

[0069] Conjugated diene monomer units refer to structural units derived from conjugated diene compounds in polymer blocks or block copolymers formed by the polymerization of conjugated diene compounds.

[0070] Conjugated dienes are dienes that have a pair of conjugated double bonds.

[0071] Examples of conjugated diene compounds include, but are not limited to, 1,3-butadiene, 2-methyl-1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, and 1,3-cyclohexadiene.

[0072] Among these, 1,3-butadiene and isoprene are preferred, and 1,3-butadiene is more preferred. 1,3-Butadiene and isoprene are widely used and readily available, and are also advantageous in terms of cost. They are also easy to copolymerize with styrene, which is widely used as a vinyl aromatic compound as described later.

[0073] These compounds can be used alone or in combination of two or more.

[0074] In addition, the aforementioned conjugated diene compounds can be biologically derived compounds.

[0075] Vinyl aromatic monomer units refer to structural units derived from vinyl aromatic compounds in polymer blocks or block copolymers formed by the polymerization of vinyl aromatic compounds.

[0076] Examples of vinyl aromatic compounds include, but are not limited to, styrene, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylethylene, N,N-dimethyl-p-aminoethylstyrene, N,N-diethyl-p-aminoethylstyrene, etc.

[0077] These compounds can be used alone or in combination of two or more.

[0078] The block copolymer of this embodiment has: a polymer block (A) mainly composed of vinyl aromatic monomer units; a polymer block (B) mainly composed of conjugated diene monomer units; and / or a polymer block (C) composed of vinyl aromatic monomer units and conjugated diene monomer units.

[0079] That is, having polymer block (A) and polymer block (B), or having polymer block (A) and polymer block (C), or having polymer block (A), polymer block (B) and polymer block (C).

[0080] The polymer block (A) is primarily composed of vinyl aromatic monomer units. "Primarily composed of vinyl aromatic monomer units" means that it is essentially composed of vinyl aromatic monomer units, and that no other monomers are intentionally added.

[0081] The polymer block (B) is predominantly composed of conjugated diene monomer units. "Predominantly composed" means that it is essentially composed of conjugated diene monomer units, and that no other monomers besides the conjugated diene monomer units are intentionally added.

[0082] The content of polymer block (A) in the block copolymer of this embodiment can be determined as follows: the block copolymer before hydrogenation or the hydrogenated block copolymer after hydrogenation is used as the analyte and determined by nuclear magnetic resonance (NMR) method (the method described in Y. Tanaka, et al., RUBBER CHEMISTRY and TECHNOLOGY 54,685 (1981), hereinafter referred to as "NMR method").

[0083] From the perspective of the increased strength of the cured product resulting from the intertwining of polymer blocks (A) composed of vinyl aromatic monomer units, as described later, the content of polymer blocks (A) in the block copolymer of this embodiment is preferably 15 to 95% by mass, more preferably 20 to 90% by mass, and even more preferably 25 to 85% by mass.

[0084] In the case where the block copolymer of this embodiment contains polymer block (B), the content of polymer block (B) can be determined by NMR.

[0085] From the perspective of the reactivity and compatibility of the polymer blocks (B) composed of conjugated diene monomer units with each other, and / or the block copolymer described above with components (II), (III) and (IV) described below, the content of polymer blocks (B) in the block copolymer of this embodiment is preferably 5 to 45% by mass, more preferably 10 to 40% by mass, and even more preferably 15 to 35% by mass.

[0086] The polymer block (C) is composed of vinyl aromatic monomer units and conjugated diene monomer units, and does not contain monomers other than vinyl aromatic monomer units and conjugated diene monomer units.

[0087] Polymer block (C) has a structure in which vinyl aromatic monomer units and conjugated diene monomer units are intentionally used as structural units, which distinguishes it from polymer block (A) and polymer block (B) mentioned above.

[0088] The vinyl aromatic compounds and conjugated diene compounds used to form the vinyl aromatic monomer units and conjugated diene monomer units contained in the polymer block (C) can be any compounds that can be used in the polymer blocks (A) and (B) described above.

[0089] There are no particular limitations on the distribution of vinyl aromatic monomer units in the polymer block (C) described above. The vinyl aromatic monomer units can be uniformly distributed in the random copolymer block, or they can be distributed in a gradient. In addition, there can be multiple portions of uniformly distributed vinyl aromatic monomer units and / or portions of gradient distribution, or there can be multiple segments with different contents of vinyl aromatic monomer units.

[0090] In the case where the block copolymer of this embodiment contains polymer blocks (C), the content of the polymer blocks (C) can be determined by NMR.

[0091] From the perspective of the reactivity and compatibility of the conjugated diene monomer units in the polymer block (C) with each other, and / or with the block copolymer described below and components (II), (III) and (IV), the content of polymer block (C) in the block copolymer of this embodiment is preferably 20 to 90% by mass, more preferably 35 to 85% by mass, further preferably 30 to 80% by mass, even more preferably 35 to 75% by mass, and even more preferably 40 to 70% by mass.

[0092] The block copolymer of this embodiment can have copolymer blocks (D) formed by copolymerizing other compounds other than the polymer blocks (A) to (C) with conjugated diene compounds and / or vinyl aromatic compounds, within a range that does not impair the dielectric properties of the desired cured product, that is, within a range that does not impair the low dielectric loss tangent and low dielectric constant.

[0093] For example, in the case of manufacturing the block copolymer of this embodiment containing copolymer blocks (D) by anionic polymerization, methyl methacrylate (MMA) can be copolymerized with vinyl aromatic compounds and conjugated diene compounds. However, if MMA is contained, there is a tendency for the dielectric properties of the block copolymer of this embodiment to decrease, that is, for the dielectric constant and / or dielectric loss tangent to increase.

[0094] The structure of the block copolymer in this embodiment is not particularly limited. For example, block copolymers having the structure shown in the following formula can be cited.

[0095] (ab) n b-(ab) n a-(ba) n (ab) m-X、(b-a) m -X、[(a-b) n ] m -X、[(b-a) n ] m -X、[b-(a-b) n ] m -X、[a-(b-a) n ] m -X、[(a-b) n -a] m -X、[(b-a) n -b] m -X、

[0096] (a-c) n 、c-(a-c) n 、a-(c-a) n 、(a-c) m -X、(c-a) m -X、[(a-c) n ] m -X、[(c-a) n ] m -X、[c-(a-c) n ] m -X、[a-(c-a) n ] m -X、[(a-c) n -a] m -X、[(c-a) n -c] m -X、

[0097] c-(b-a) n 、c-(a-b) n 、

[0098] c-(a-b-a) n 、c-(b-a-b) n 、

[0099] a-c-(b-a) n 、a-c-(a-b) n 、

[0100] a-c-(b-a) n -b、[(a-b-c) n ] m -X、

[0101] [a-(b-c) n ] m -X、[(a-b) n -c] m-X、

[0102] [(a-b-a) n -c] m -X、

[0103] [(b-a-b) n -c] m -X、[(c-b-a) n ] m -X、

[0104] [c-(b-a) n ] m -X、[c-(a-b-a) n ] m -X、[c-(b-a-b) n ] m -X

[0105] a-(b-c) n 、a-(c-b) n 、

[0106] a-(c-b-c) n 、a-(b-c-b) n 、

[0107] c-a-(b-c) n 、c-a-(c-b) n 、

[0108] c-a-(b-c) n -b、[(c-b-a) n ] m -X、

[0109] [c-(b-a) n ] m -X、[(c-b) n -a] m -X、

[0110] [(c-b-c) n -a] m -X、

[0111] [(b-c-b) n -a] m -X、[(a-b-c) n ] m -X、

[0112] [a-(b-c) n ] m -X、[a-(c-b-c) n ] m-X、[a-(bcb) n ] m -X

[0113] b-(ac) n b-(ca) n ,

[0114] b-(cac) n b-(aca) n ,

[0115] cb-(ac) n cb-(ca) n ,

[0116] cb-(ac) n -a、[(cab) n ] m -X、

[0117] [c-(ab) n ] m -X、[(ca) n -b] m -X、

[0118] [(cac) n -b] m -X、

[0119] [(bac) n ] m -X、

[0120] [b-(ac) n ] m -X、[b-(cac) n ] m -X、[b-(aca) n ] m -X

[0121] It should be noted that in the above general formulas, a represents the polymer block (A), b represents the polymer block (B), and c represents the polymer block (C).

[0122] n is an integer greater than or equal to 1, preferably an integer between 1 and 5.

[0123] m is an integer greater than or equal to 2, preferably an integer between 2 and 11.

[0124] X represents a residue of a coupling agent or a residue of a multifunctional initiator.

[0125] The polymer block (A) is a polymer block mainly composed of vinyl aromatic monomer units, and is therefore amorphous. In the resin composition and cured product of this embodiment described later, the presence of polymer block (A) improves the intertwining strength and heat resistance.

[0126] Polymer blocks (B) are polymer blocks with conjugated diene monomer units as the main body, and therefore have free radical reactivity.

[0127] In the resin composition and cured product of this embodiment described later, there is a tendency for improved heat resistance due to the reaction between the polymer blocks and / or the block copolymers of this embodiment.

[0128] When the block copolymer of this embodiment forms a resin composition with the following components (III) and / or (IV) which do not have free radical reactivity, the conjugated diene monomer unit is less sterically hindered than the vinyl aromatic monomer unit, and therefore is also compatible with components (III) and / or (IV). The resin composition and cured product of this embodiment tend to have excellent strength and heat resistance.

[0129] Furthermore, by improving the reactivity and compatibility of the polymer blocks and / or block copolymers, the decrease in polymer mobility and polarization caused by the external electric field can be suppressed in the resin composition and cured product of this embodiment described later, and the resin composition and cured product exhibit low dielectric loss tangent and low dielectric constant.

[0130] Polymer block (C) is a polymer block containing vinyl aromatic monomer units and conjugated diene monomer units. Therefore, it is expected that the strength improvement effect will be achieved by intertwining with the polymer block (A) which is mainly composed of vinyl aromatic monomer units, as well as the improvement effect on free radical reactivity and compatibility with other components besides polymer blocks (A) and (B). On the other hand, from the perspective of the strength improvement brought about by intertwining, it tends to be worse than the strength improvement effect brought about by the intertwining of polymer blocks (A) with each other.

[0131] As described below, the resin composition of this embodiment comprises the block copolymer of this embodiment (component (I)) and component (II): free radical initiator, component (III): polar resin, and component (IV): curing agent.

[0132] Components (II), (III) and (IV) have polar groups.

[0133] From the perspective of solubility parameters, vinyl aromatic compounds have better compatibility with components (II), (III), and (IV) than conjugated diene compounds. However, the block copolymer of this embodiment has reduced steric hindrance when copolymerizing with conjugated diene compounds. If a polymer block (C) is present, the compatibility with components (III) and (IV) is improved.

[0134] In this embodiment, in order to obtain a resin composition and cured product with high strength, low dielectric loss tangent and low dielectric constant, from the perspective of the intertwining of polymers composed of vinyl aromatic compounds, the block copolymer of this embodiment has polymer blocks (A) mainly composed of vinyl aromatic monomer units, and from the perspective of the above-mentioned reactivity and / or compatibility, it has polymer blocks (B) and / or polymer blocks (C).

[0135] Furthermore, as a component (III) of the resin composition constituting this embodiment: polar resin, when using a resin containing an aromatic ring, such as a polyphenylene ether resin, the block copolymer of this embodiment tends to have improved compatibility and further improved strength of the cured product by containing polymer blocks (A) mainly composed of vinyl aromatic monomer units.

[0136] The block copolymer contained in the resin composition of this embodiment satisfies conditions (i) and (ii).

[0137] <Condition(i)>

[0138] The block copolymer of this embodiment has a weight-average molecular weight of less than 35,000.

[0139] Regarding the weight-average molecular weight, it is determined by measuring the molecular weight of the peaks in a chromatogram obtained by gel permeation chromatography (GPC) based on a calibration curve derived from the determination of commercially available standard polystyrene (using the peak molecular weight of the standard polystyrene). Specifically, the determination can be performed using the methods described in the examples below.

[0140] The molecular weight distribution is the ratio of weight-average molecular weight (Mw) to number-average molecular weight (Mn) (Mw / Mn).

[0141] The molecular weight distribution of the block copolymer of this embodiment, as determined by GPC, is preferably 5.0 or less, more preferably 4.0 or less, even more preferably 3.0 or less, and even more preferably 2.5 or less.

[0142] By making the weight-average molecular weight of the block copolymer of this embodiment less than 35,000, the compatibility with component (III): polar resin and component (IV): curing agent constituting the resin composition of this embodiment described later can be improved, thereby increasing the strength of the resin composition and the cured product, and achieving low dielectric loss tangent and low dielectric constant.

[0143] Furthermore, when using the resin composition of this embodiment to prepare a prepreg, when impregnating a substrate such as glass cloth described later with the varnish described later, by making the weight-average molecular weight of the block copolymer of this embodiment less than 35,000, it tends to improve the permeability to the substrate and produce a uniform prepreg.

[0144] Based on the above, the weight-average molecular weight of the block copolymer in this embodiment is preferably 30,000 or less, more preferably 25,000 or less, even more preferably 20,000 or less, further preferably 15,000 or less, and even more preferably 10,000 or less. The lower limit is not particularly limited, but from the perspective of suppressing the stickiness of the block copolymer in this embodiment and ensuring good processability, a weight-average molecular weight of 500 or more is preferred.

[0145] The weight-average molecular weight and molecular weight distribution of the block copolymer in this embodiment can be controlled to the above-mentioned range by adjusting polymerization conditions such as monomer addition amount, addition timing, polymerization temperature, and polymerization time.

[0146] <Condition(ii)>

[0147] In this embodiment, the content of vinyl aromatic monomer units in the block copolymer is 55% by mass or more and 95% by mass or less.

[0148] By using the above numerical range, from the perspective of solubility parameters, it tends to have excellent compatibility with components (II), (III), and (IV) described later.

[0149] By making the content of vinyl aromatic monomer units in the block copolymer of this embodiment 55% by mass or more, the compatibility with components (II), (III) and (IV) described later is improved, and there is a tendency to improve the strength of the resin composition and cured product of this embodiment, as well as to achieve a lower dielectric loss tangent and a lower dielectric constant.

[0150] Furthermore, from the perspective of solubility parameters, the content of vinyl aromatic monomer units in the block copolymer of this embodiment is preferably 57% by mass or more, more preferably 60% by mass or more, even more preferably 63% by mass or more, even more preferably 65% ​​by mass or more, and particularly preferably 67% by mass or more.

[0151] By ensuring that the content of vinyl aromatic monomer units is 95% by mass or less, the reactivity with components (II), (III), and (IV) described later, as well as the reactivity with each other of the block copolymer of this embodiment, can be guaranteed. Preferably, it is 90% by mass or less, more preferably 85% by mass or less.

[0152] According to the inventors' understanding, the dielectric properties of block copolymers are somewhat related to the state of the cured product. By curing the block copolymer of this embodiment in a state of reaction or compatibility with other components, the molecular chains become less mobile, tending to improve the dielectric properties of the cured product, i.e., to reduce the dielectric constant. Therefore, from the perspective of improving the dielectric properties of the cured product, it is preferable to control not only the dielectric constant or dielectric properties of the block copolymer of this embodiment, but also the reactivity and compatibility with other components.

[0153] If the content of vinyl aromatic monomer units in the block copolymer of this embodiment is 55% by mass or more, the compatibility with components (II), (III) and (IV) described later becomes good. The increased entanglement caused by the aggregation of polymer blocks (A) mainly composed of vinyl aromatic monomer units enables high strength and allows for the pursuit of low dielectric loss tangent and low dielectric constant.

[0154] The content of vinyl aromatic monomer units in the block copolymer (I) can be controlled to the above-mentioned value range by adjusting the amount of monomer added, the timing of addition, polymerization temperature and other polymerization conditions. Specifically, it can be calculated by the method described in the following examples.

[0155] The block copolymer of this embodiment preferably also satisfies condition (iii).

[0156] <Condition (iii)>

[0157] The polymer block (B) and / or the polymer block (C) described above contain units (a) (sometimes referred to as unit (a)) derived from 1,2-bonding and / or 3,4-bonding and units (b) (sometimes referred to as unit (b)) derived from 1,4-bonding, wherein when the total content of conjugated diene monomer units in the polymer block (B) and / or the polymer block (C) is set to 100%, the content of the units (a) derived from 1,2-bonding and / or 3,4-bonding is 80% or less.

[0158] It should be noted that in the calculation of the content of unit (a) in the block copolymer, when the block copolymer contains both polymer block (B) and polymer block (C), the total content of conjugated diene monomer units in polymer block (B) and polymer block (C) is set to 100%; when it contains only polymer block (B), the content of polymer block (B) is set to 100%; and when it contains only polymer block (C), the content of conjugated diene monomer units in polymer block (C) is set to 100%.

[0159] In addition, in the case of including both 1,2-bonding and 3,4-bonding, the total content of 1,2-bonding and 3,4-bonding is the content of unit (a) (vinyl bond amount).

[0160] Compared to unit (b), the above-described unit (a) has higher free radical reactivity. When storing the resin composition of this embodiment (described later) or the resin varnish containing the block copolymer of this embodiment before curing, the resin composition and resin varnish tend to exhibit sufficient storage stability by keeping the content of the above-described unit (a) at 80% or less.

[0161] From the perspective of the reactivity between the conjugated diene monomer units in the block copolymer of this embodiment and the reactivity of the block copolymer with other components, the lower limit of the content of the above-mentioned unit (a) is preferably 20% or more, more preferably 30% or more, further preferably 40% or more, and even more preferably 50% or more.

[0162] The content of the above-mentioned unit (a) can be controlled to the above-mentioned numerical range during polymerization by using regulators such as polar compounds, and can be calculated using the method described in the following examples.

[0163] Examples of modifiers include tertiary amine compounds and ether compounds. Tertiary amine compounds are preferred.

[0164] Tertiary amine compounds are compounds with the general formula R1R2R3N (where R1, R2, and R3 are hydrocarbon groups with 1 to 20 carbon atoms, or hydrocarbon groups having a tertiary amino group).

[0165] Examples of tertiary amine compounds include, but are not limited to, trimethylamine, triethylamine, tributylamine, N,N-dimethylaniline, N-ethylpiperidine, N-methylpyrrolidine, N,N,N',N'-tetramethylethylenediamine, N,N,N',N'-tetraethylethylenediamine, 1,2-dipiperidinylethane, trimethylaminoethylpiperazine, N,N,N',N”,N”-pentamethylethylenetriamine, and N,N'-dioctyl-p-phenylenediamine.

[0166] The block copolymer in this embodiment can be a hydrogenated block copolymer based on the hydrogenation of aliphatic double bonds of conjugated diene compounds, within a range that does not impair the curing reaction.

[0167] There are no particular limitations on the method for hydrogenating block copolymers; previously known methods can be applied.

[0168] A hydrogenation catalyst can be used in the above hydrogenation reaction.

[0169] As hydrogenation catalysts, for example, the following are used: (1) supported heterogeneous hydrogenation catalysts formed by supporting metals such as Ni, Pt, Pd, and Ru on carbon, silicon oxide, aluminum oxide, diatomaceous earth, etc.; (2) so-called Ziegler-type hydrogenation catalysts using transition metal salts such as organic acid salts or acetylacetone salts of Ni, Co, Fe, Cr, etc. and reducing agents such as organoaluminum; (3) so-called homogeneous hydrogenation catalysts such as organometallic compounds of Ti, Ru, Rh, Zr, etc.

[0170] Specifically, the hydrogenation catalysts described in Japanese Patent Publication Nos. 42-8704, 43-6636, 63-4841, 1-37970, 1-53851, and 2-9041 may be used as hydrogenation catalysts.

[0171] Preferred hydrogenation catalysts include cyclopentadiene titanium compounds and / or reducing organometallic compounds.

[0172] As cyclopentadiene titanium compounds, compounds described in Japanese Patent Application Publication No. 8-109219 may be used. Examples of cyclopentadiene titanium compounds include dicyclopentadiene titanium dichloride and mono(pentamethylcyclopentadienyl)titanium trichloride, which are compounds having at least one ligand with a (substituted) cyclopentadiene skeleton, an indenyl skeleton, or a fluorenyl skeleton. Cyclopentadiene titanium compounds may contain one or two of the aforementioned skeletons, either individually or in combination.

[0173] Examples of reducing organometallic compounds include organolithium compounds, organomagnesium compounds, organoaluminum compounds, organoboron compounds, and organozinc compounds. They can be used individually or in combination of two or more.

[0174] The hydrogenation rate of the block copolymer can be controlled by adjusting the reaction temperature, reaction time, hydrogen supply, and catalyst amount in the hydrogenation method as needed. Regarding the temperature of the hydrogenation reaction, it is preferably carried out at 55–200°C, more preferably at 60–170°C, and even more preferably at 65–160°C. Furthermore, the pressure of the hydrogen used in the hydrogenation reaction is preferably 0.1–15 MPa, more preferably 0.2–10 MPa, and even more preferably 0.3–5 MPa. Additionally, the hydrogenation reaction time is typically 3 minutes to 10 hours, preferably 10 minutes to 5 hours.

[0175] Hydrogenation can be carried out using batch processes, continuous processes, or a combination thereof.

[0176] When the curing reaction to obtain the cured product of this embodiment described later is a free radical reaction, from the perspective of balancing the curing reactivity and thermal stability, the hydrogenation rate of the block copolymer of this embodiment is preferably 5 to 95%, more preferably 10 to 90%, and even more preferably 13 to 87%. When the curing reaction is not a free radical reaction, from the perspective of the compatibility of the block copolymer of this embodiment with other components, the hydrogenation rate can be arbitrarily selected between 0 and 100%.

[0177] [Method for manufacturing block copolymers]

[0178] The block copolymer of this embodiment can be manufactured, for example, by active anionic polymerization using a polymerization initiator such as an organoalkali metal compound in a hydrocarbon solvent.

[0179] Examples of hydrocarbon solvents include aliphatic hydrocarbons such as n-butane, isobutane, n-pentane, n-hexane, n-heptane, and n-octane; alicyclic hydrocarbons such as cyclohexane, cycloheptane, and methylcycloheptane; aromatic hydrocarbons such as benzene, toluene, xylene, and ethylbenzene; and so on.

[0180] As polymerization initiators, examples include aliphatic hydrocarbon alkali metal compounds, aromatic hydrocarbon alkali metal compounds, and organic amino alkali metal compounds, which are generally known to have anionic polymerization activity for conjugated diene compounds and vinyl aromatic compounds.

[0181] Examples of alkali metals include lithium, sodium, and potassium.

[0182] Examples of organoalkali metal compounds include aliphatic and aromatic hydrocarbon lithium compounds with 1 to 20 carbon atoms, including compounds containing one lithium atom in one molecule, dilithium compounds, trilithium compounds, and tetralithium compounds containing multiple lithium atoms in one molecule.

[0183] Specifically, examples of organoalkali metal compounds include n-propyllithium, n-butyllithium, sec-butyllithium, tert-butyllithium, n-pentyllithium, n-hexyllithium, benzyllithium, phenyllithium, tolyllithium, the reaction product of diisopropylbenzene with sec-butyllithium, and the reaction product of divinylbenzene with sec-butyllithium and a small amount of 1,3-butadiene. Additionally, alkyl lithiums containing siloxy groups, such as 1-(tert-butoxy)propyllithium disclosed in US Patent 5,708,092 and lithium compounds containing one to several molecules of isoprene monomer inserted to improve their solubility, alkyl lithiums containing siloxy groups, such as 1-(tert-butyldimethylsiloxy)hexyllithium disclosed in British Patent 2,241,239, and amino lithiums such as alkyl lithiums containing amino groups, lithium diisopropylamine, and lithium hexamethyldisilazum disclosed in US Patent 5,527,753.

[0184] As a method for polymerizing vinyl aromatic compounds and conjugated diene polymers using organoalkali metal compounds as polymerization initiators, existing known methods can be applied.

[0185] The polymerization method can be, for example, batch polymerization, continuous polymerization, or a combination thereof. Batch polymerization is preferred to obtain homogeneous polymer blocks.

[0186] The polymerization temperature is preferably 0°C to 180°C, more preferably 30°C to 150°C. The polymerization time varies depending on the conditions, but is typically within 48 hours, preferably 0.1 to 10 hours. Furthermore, an inert gas atmosphere such as nitrogen is preferred for the polymerization system. Regarding the polymerization pressure, it is not particularly limited as long as it is set within a pressure range sufficient to maintain the monomer and solvent in a liquid phase within the aforementioned temperature range. In addition, care should be taken to avoid introducing impurities such as water, oxygen, and carbon dioxide into the polymerization system that could deactivate the catalyst and active polymer.

[0187] In addition, at the end of the above polymerization process, a coupling agent with two or more functions can be added to carry out a coupling reaction. The coupling rate is preferably 40% or less, more preferably 30% or less, further preferably 20% or less, and even more preferably does not contain a coupling agent.

[0188] As a difunctional coupling agent, any existing known coupling agents can be used without particular limitation.

[0189] Examples of difunctional coupling agents include, but are not limited to, alkoxysilane compounds such as trimethoxysilane, triethoxysilane, tetramethoxysilane, tetraethoxysilane, dimethyldimethoxysilane, diethyldimethoxysilane, dichlorodimethoxysilane, dichlorodiethoxysilane, trichloromethoxysilane, and trichloroethoxysilane; dihalides such as dichloroethane, dibromoethane, dimethyldichlorosilane, and dimethyldibromosilane; and esters such as methyl benzoate, ethyl benzoate, phenyl benzoate, and phthalates.

[0190] In addition, as a multifunctional coupling agent with three or more functions, any existing known coupling agents can be used without particular limitation.

[0191] Examples of multifunctional coupling agents with three or more functions include, but are not limited to, polyols with three or more nucleotides; epoxidized soybean oil, diglycidyl bisphenol A, 1,3-bis(N-N'-diglycidylaminomethyl)cyclohexane, and other polyepoxide compounds; and compounds with the general formula R4-nSiX. n (Here, R represents a hydrocarbon group with 1 to 20 carbon atoms, X represents a halogen, and n represents an integer from 3 to 4) represents silicon halide compounds, such as methyltrichlorosilane, tert-butyltrichlorosilane, silicon tetrachloride, and their bromides; general formula R4-nSnX n (Here, R represents a hydrocarbon group with 1 to 20 carbon atoms, X represents a halogen, and n represents an integer from 3 to 4.) The tin halide compounds represented are, for example, methyltin trichloride, tert-butyltin trichloride, tin tetrachloride, and other polyhalides. Additionally, dimethyl carbonate, diethyl carbonate, etc., can also be used.

[0192] For the block copolymer solution obtained according to the above embodiment, catalyst residue can be removed as needed to separate the block copolymer from the solution.

[0193] In the process of manufacturing block copolymers via anionic active polymerization, compounds containing metal atoms in the polymerization initiator and the hydrogenation catalyst in the aforementioned hydrogenation reaction react with moisture in the air during the desolventizing process, generating specific metal compounds that tend to remain in the block copolymer. If these compounds are included in the cured product, the dielectric constant and dielectric loss tangent tend to increase, and consequently, they tend to exhibit a tendency to induce ion migration in electronic material applications.

[0194] Examples of residual metal compounds include compounds containing metals in polymerization initiators and hydrogenation catalysts, such as titanium oxide, amorphous titanium oxide, orthotitanic acid or metatitanic acid, titanium hydroxide, nickel hydroxide, nickel monoxide, lithium oxide, lithium hydroxide, cobalt oxide, cobalt hydroxide, etc., oxides containing each atom of these metals, lithium titanate, barium titanate, strontium titanate, nickel titanate, nickel-iron oxide, etc., and composite oxides of each atom of these metals with dissimilar metals.

[0195] In the cured resin composition of this embodiment, from the perspective of achieving a low dielectric constant, a low dielectric loss tangent, and minimal ion migration, the residual amount of metal compound in the block copolymer is preferably 150 ppm or less, more preferably 130 ppm or less, further preferably 100 ppm or less, and even more preferably 90 ppm or less, in terms of residual metal content. Specific examples of residual metals include Ti, Ni, Li, and Co.

[0196] As a method for reducing the residual metal content in the block copolymer of this embodiment, any known method can be used, and there is no particular limitation. For example, a method of neutralizing the hydrogenation catalyst residue by adding water and carbon dioxide after the hydrogenation reaction of the block copolymer; or a method of neutralizing the hydrogenation catalyst residue by adding an acid in addition to water and carbon dioxide. Specifically, the method described in Japanese Patent Application 2014-557427 can be used. Even with these metal removal methods, since water containing metal compounds as hydroxides is mixed in during the desolventizing process of the block copolymer, the residual metal usually contains about 1 to 15 ppm. Therefore, relative to the amount of metal added to the block copolymer, it is preferable to remove 20% or more, more preferably 30% or more, further preferably 40% or more, even more preferably 50% or more, and even more preferably 60% or more.

[0197] Furthermore, reducing the amount of added polymerization initiator and hydrogenation catalyst can also reduce the amount of residual metal in the block copolymer. However, if the amount of polymerization initiator is reduced, the molecular weight of the block copolymer increases. If it falls outside the preferred molecular weight range mentioned above, the strength of the cured product tends to decrease. In addition, during the hydrogenation reaction, reducing the amount of hydrogenation catalyst results in a longer hydrogenation reaction time and a higher hydrogenation reaction temperature, which tends to significantly reduce productivity.

[0198] Examples of solvent separation methods for removing block copolymers from a solution include: adding a polar solvent such as acetone or alcohol, which is a poor solvent for block copolymers, to the hydrogenated reaction solution to precipitate the block copolymers and then recovering them; adding the reaction solution to hot water under stirring and removing the solvent by stripping; directly heating the block copolymer solution and distilling to remove the solvent; and so on.

[0199] It should be noted that various phenolic stabilizers, phosphorus stabilizers, sulfur stabilizers, amine stabilizers, and other stabilizers can be added to the hydrides of block copolymers.

[0200] The block copolymer of this embodiment can have "polar groups" within a range that does not impair dielectric properties.

[0201] As a "polar group", examples include, but are not limited to, functional groups selected from the group consisting of hydroxyl, carboxyl, carbonyl, thiocarbonyl, acyl halide, acid anhydride, carboxylic acid, thiocarboxylic acid, aldehyde, thioaldehyde, carboxylic acid ester, amide, sulfonic acid, sulfonate, phosphoric acid, phosphate ester, amino, imino, nitrile, pyridinyl, quinolinyl, epoxy, thioepoxy, thioether, isocyanate, isothiocyanate, silyl halide, silanol, alkoxysilyl, tin halide, borate, boron-containing, borate, alkoxytin, and phenyltin, as well as groups containing at least one of these functional groups.

[0202] The aforementioned "polar groups" can be formed using modifiers.

[0203] Examples of modifiers include, but are not limited to, tetraglycidyl-m-phenylenediamine, tetraglycidyl-1,3-diaminomethylcyclohexane, ε-caprolactone, δ-valerolactone, 4-methoxybenzophenone, γ-glycidyloxyethyltrimethoxysilane, γ-glycidyloxypropyltrimethoxysilane, γ-glycidyloxypropyldimethylphenoxysilane, bis(γ-glycidyloxypropyl)methylpropoxysilane, 1,3-dimethyl-2-imidazolinone, 1,3-diethyl-2-imidazolinone, N,N'-dimethylacrylurea, N-methylpyrrolidone, maleic acid, maleic anhydride, maleic anhydride imide, fumaric acid, itaconic acid, acrylic acid, methacrylic acid, glycidyl methacrylate, crotonic acid, etc.

[0204] As a method for forming "polar groups", any known method can be used, and there are no particular limitations.

[0205] Examples include: melt mixing methods; methods that dissolve or disperse the components in a solvent or the like and allow them to react; and so on. Additionally, examples include: methods of polymerization using anionic living polymerization initiators or unsaturated monomers with functional groups; methods of modification by adding modifiers that form or contain functional groups at active ends; methods of reacting organoalkali metal compounds such as organolithium compounds with block copolymers (metallization reactions); and methods of adding modifiers with functional groups to block polymers containing organoalkali metals.

[0206] [Resin Composition]

[0207] The resin composition in this embodiment comprises the block copolymer of this embodiment (component (I)) and at least one component selected from the group consisting of components (II) to (IV) below.

[0208] Component (II): Free radical initiator

[0209] Component (III): Polar resin (excluding component (I))

[0210] Component (IV): Hardener (excluding component (II))

[0211] From the perspectives of low dielectric constant, low dielectric loss tangent, and flexibility of the resin composition and its cured product of this embodiment, the resin composition of this embodiment preferably includes component (I): the above-mentioned block copolymer and component (II): free radical initiator.

[0212] (Component (II): Free radical initiator)

[0213] As free radical initiators, existing known substances can be used, such as thermal free radical initiators.

[0214] Examples of thermal free radical initiators include, but are not limited to, hydrogen peroxide derivatives such as dicumyl hydroperoxide (Percumyl P), cumyl hydroperoxide (Percumyl H), and tert-butyl hydroperoxide (Perbutyl H); α,α-bis(tert-butylperoxide-m-isopropyl)benzene (Perbutyl P), dicumyl peroxide (Percumyl D), 2,5-dimethyl-2,5-bis(tert-butylperoxide)hexane (PERHEXA25B), tert-butylcumyl peroxide (Perbutyl C), di-tert-butyl peroxide (Perbutyl D), 2,5-dimethyl-2,5-bis(tert-butylperoxide)-3-hexyne (Perhexyne 25B), and tert-butyl peroxide (2-ethylhexanoic acid) (Perbutyl Dialkyl peroxides such as O; peroxide ketones; peroxide ketals such as 4,4-bis(tert-butylperoxy)valerate (PERHEXAV); peroxide diacyls; peroxide dicarbonates; organic peroxide esters; azo compounds such as 2,2-azobisisobutyronitrile, 1,1'-(cyclohexane-1-1-carboxynitrile), 2,2'-azobis(2-cyclopropylpropionitrile), and 2,2'-azobis(2,4-dimethylvalerate); etc.

[0215] These substances can be used alone or in combination with more than one.

[0216] (Component (III): Polar resin)

[0217] From the perspective of imparting properties such as adhesion to a specified substrate, the resin composition of this embodiment may contain component (III): a polar resin (excluding component (I)) within a range that does not impair the dielectric properties such as low dielectric constant and low dielectric loss tangent of the cured product. By containing a polar resin, the resin composition of this embodiment tends to have excellent adhesion to a specified substrate.

[0218] In the case where component (III) is a polar resin with free radical reactivity, the amount of free radical initiator in component (II) can be adjusted appropriately according to the reactivity, or component (II) can be omitted.

[0219] As component (III), a polar resin with free radical reactivity can be exemplified by homopolymers and / or copolymers of compounds containing at least one vinyl and / or halogen element in the polymer. From a reactivity perspective, the presence of vinyl groups is preferred.

[0220] Polymers containing vinyl groups can be polymers composed of repeating units containing vinyl groups, polymers reacted with compounds containing vinyl groups and polar groups, or polymers containing vinyl groups obtained by reacting the polar groups of compounds containing polar groups.

[0221] Examples of compounds containing vinyl groups and polar groups include, for instance, carboxyl-containing vinyl monomers such as (meth)acrylic acid (in this specification, "(meth)acrylic acid" refers to methacrylic acid or acrylic acid), maleic acid, monoalkyl maleate, and fumaric acid; sulfone-containing vinyl monomers such as vinyl sulfonic acid, (meth)allyl sulfonic acid, methyl vinyl sulfonic acid, and styrene sulfonic acid; hydroxyl-containing vinyl monomers such as hydroxystyrene, N-hydroxymethyl(meth)acrylamide, hydroxyethyl(meth)acrylate, and hydroxypropyl(meth)acrylate; phosphate-containing vinyl monomers such as 2-hydroxyethyl(meth)acryloyl phosphate, phenyl-2-acryloyloxyethyl phosphate, and 2-acryloyloxyethylphosphonic acid; and hydroxystyrene, N... hydroxyl-containing vinyl monomers such as hydroxymethyl (meth)acrylamide, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, polyethylene glycol (meth)acrylate, and 1-buten-3-ol; amino-containing vinyl monomers such as aminoethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, and diethylaminoethyl (meth)acrylate; amide-containing vinyl monomers such as (meth)acrylamide, N-methyl (meth)acrylamide, and N-butylacrylamide; nitrile-containing vinyl monomers such as (meth)acrylonitrile, cyanostyrene, and cyanoacrylate; and epoxy-containing vinyl monomers such as glycidyl methacrylate, tetrahydrofurfuryl (meth)acrylate, and p-vinylphenylphenyl oxide.

[0222] Examples of compounds containing halogens include vinyl chloride, vinyl bromide, vinylidene chloride, allyl chloride, chlorostyrene, bromostyrene, dichlorostyrene, chloromethylstyrene, tetrafluorostyrene, and chloroprene.

[0223] (Component (IV): Curing agent)

[0224] In the case that the free radical reactivity of the above-mentioned component (III) is low, from the perspective of reactivity, the resin composition of this embodiment preferably contains component (IV): curing agent (excluding component (II)).

[0225] Component (IV): The curing agent typically has the function of reacting with component (III): the polar resin to cure the resin composition.

[0226] The "reaction" of components (III) and (IV) refers to the covalent bonding between the polar groups of each component. When polar groups react with each other, for example, if the OH group of a carboxyl group is removed, the original polar group changes or disappears, thereby forming a covalent bond. This is included in the definition of "reactivity" of polar groups with each other.

[0227] From the perspective of curing function, component (IV): curing agent preferably has at least two polar groups in one molecular chain that can react with the functional groups of component (III): polar resin.

[0228] Component (IV) can be used alone or in combination of two or more.

[0229] The types of polar groups present in components (III) and (IV) are not particularly limited; for example:

[0230] Epoxy groups are associated with carboxyl, carbonyl, ester, imidazole, hydroxyl, amino, thiol, benzoxazine, carbodiimide, and phenolic hydroxyl groups.

[0231] Amino groups, carboxyl groups, carbonyl groups, hydroxyl groups, acid anhydride groups, sulfonic acid groups, and aldehyde groups;

[0232] Isocyanate groups are associated with hydroxyl groups, carboxylic acids, and phenolic hydroxyl groups;

[0233] Anhydride group and hydroxyl group;

[0234] Silanol group and hydroxyl, carboxylic acid group;

[0235] Halogenated groups and carboxylic acid groups, carboxylic acid ester groups, amino groups, phenolic groups, and mercapto groups;

[0236] Alkoxy groups, hydroxyl groups, alkoxide groups, and amino groups;

[0237] Maleimide group and cyanate ester group, etc.

[0238] Whether the bonding of these polar groups is component (III) or component (IV) can be arbitrarily chosen.

[0239] In addition, the situation where the polar groups of component (III) and the polar groups of component (IV) do not react directly, but can react by adding a curing accelerator such as a catalyst, is also included in the definition of "reactivity".

[0240] For example, in the case where component (III) is a polar resin with epoxy groups and component (IV) is a curing agent with an anhydride group, the reactivity of epoxy groups with anhydride groups is usually very low. However, by adding a compound with an amino group as a curing accelerator, the epoxy groups of component (III) react with the amino group, and some or all of the epoxy groups of component (III) become hydroxyl groups. Through the reaction of this hydroxyl group with the anhydride group of component (IV): the curing agent, the resin composition cures.

[0241] From a reactivity perspective, the ratio of component (III): polar resin to component (IV): curing agent, in terms of the molar ratio of polar groups, is preferably component (III): component (IV) = 1:0.01 to 1:20, more preferably 1:0.05 to 1:15, and even more preferably 1:0.1 to 1:10.

[0242] Composition (IV): Curing agents containing ester groups include, for example, EXB9451, EXB9460, EXB, 9460S, HPC8000-65T, HPC8000H-65TM, EXB8000L-65TM, EXB8150-65T, EXB9416-70BK manufactured by DIC Corporation, and YLH1026, DC808, YLH1026, YLH1030, and YLH1048 manufactured by Mitsubishi Chemical Corporation.

[0243] Examples of curing agents containing hydroxyl groups include MEH-7700, MEH-7810, MEH-7851, NHN, CBN, and GPH manufactured by Nippon Kayaku Co., Ltd., SN170, SN170, SN180, SN190, SN475, SN485, SN495, SN-495V, and SN375 manufactured by Nippon Steel & Sumitomo Metal Chemical Co., Ltd., and TD-2090, LA-7052, LA-7054, LA-1356, LA-3018-50P, and EXB-9500 manufactured by DIC Corporation.

[0244] Examples of curing agents containing benzoxazine groups include ODA-BOZ manufactured by JFE Chemical Co., Ltd., HFB2006M manufactured by Showa Polymer Co., Ltd., and Pd and Fa manufactured by Shikoku Chemical Co., Ltd.

[0245] Examples of curing agents with isocyanate groups include, for instance, bisphenol A dicyanate, polyphenol cyanate, oligomeric (3-methylene-1,5-phenylene cyanate), 4,4'-methylenebis(2,6-dimethylphenyl cyanate), 4,4'-ethoxydiphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis(4-cyanate)phenylpropane, 1,1-bis(4-cyanate phenylmethane), bis(4-cyanate-3,5-dimethylphenyl)methane, 1,3-bis(4-cyanate phenyl-1-(methylethoxy))benzene, bis(4-cyanate phenyl) sulfide, and bis(4-cyanate phenyl) ether, etc., which are difunctional cyanate resins; polyfunctional cyanate resins derived from phenolic varnishes and cresol varnishes, etc.; prepolymers of these cyanate resins that have undergone partial triazineization; and so on. As commercially available products, examples include PT30, PT60, ULL-950S, BA230, and BA230S75 manufactured by Lonza Japan.

[0246] Examples of curing agents containing carbodiimide groups include V-03 and V-07 manufactured by Nisshinbo Chemical Co., Ltd.

[0247] Examples of amino-containing curing agents include 4,4'-methylenebis(2,6-dimethylaniline), diphenyl diamino sulfone, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, m-phenylenediamine, m-phenylenediamine, diethyltoluenediamine, 4,4'-diaminodiphenyl ether, 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dihydroxybenzidine, and 2,2-bis(3-amino- 4-Hydroxyphenyl)propane, 3,3-dimethyl-5,5-diethyl-4,4-diphenylmethanediamine, 2,2-bis(4-aminophenyl)propane, 2,2-bis(4-(4-aminophenoxy)phenyl)propane, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, bis(4-(4-aminophenoxy)phenyl)sulfone, bis(4-(3-aminophenoxy)phenyl)sulfone, etc. Commercially available products include KAYABOND C-200S, KAYABOND C-100, KAYAHARD AA, KAYAHARD AB, KAYAHARD AS manufactured by Nippon Kayaku Co., Ltd., and Epicure W manufactured by Mitsubishi Chemical Co., Ltd.

[0248] Furthermore, from a reactivity perspective, the amino group is preferably a primary amine and / or a secondary amine, more preferably a primary amine.

[0249] Examples of curing agents containing anhydride groups include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methyl norbornene, hydrogenated methyl norbornene, trialkyltetrahydrophthalic anhydride, dodecenylsuccinic anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, trimellitic anhydride, and pyromellitic anhydride. Tetracarboxylic anhydride, benzophenone tetracarboxylic anhydride, biphenyl tetracarboxylic anhydride, naphthalene tetracarboxylic anhydride, oxydiphthalic anhydride, 3,3'-4,4'-diphenyl sulfone tetracarboxylic anhydride, 1,3,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphthol [1,2-C]furan-1,3-dione, ethylene glycol bis(triphenylamine), styrene-maleic acid resin copolymerized from styrene and maleic acid, and other polymeric anhydrides.

[0250] In addition, compounds having at least two of the aforementioned structures with free radical reactivity also have the function of reacting with component (III) to cure the resin composition. This compound can also be used as a curing agent for component (IV).

[0251] Examples of compounds having at least two structures with free radical reactivity include allyl monomers such as triallyl isocyanurate (TAIC manufactured by Mitsubishi Chemical Corporation), tris(2-hydroxyethyl) isocyanurate, diallyl fumarate, diallyl adipate, triallyl citrate, and diallyl hexahydrophthalate.

[0252] When the resin composition of this embodiment contains component (III), component (III) is a polar resin, preferably selected from the group consisting of epoxy resin, polyimide resin, polyphenylene ether resin, liquid crystal polyester resin, and fluorinated resin, from the perspective of adhesiveness. More preferably, it is selected from the group consisting of at least one of epoxy resin, polyimide resin, and polyphenylene ether resin.

[0253] As a component (III), the polyimide resin only needs to have an imide bond in the repeating unit and fall within the category of polyimide resins. For example, a general polyimide structure obtained by polycondensing a tetracarboxylic acid or its dianhydride with a diamine (forming an imide bond) can be cited. From the perspective of curability, it is preferable to have unsaturated groups at the ends of the above-mentioned polyimide structure. Examples of polyimide resins with unsaturated groups at the ends include, for example, maleimide-type polyimide resins, nadicimide-type polyimide resins, and allyl nadicimide-type polyimide resins.

[0254] Examples of tetracarboxylic acids or their dianhydrides include, but are not limited to, aromatic tetracarboxylic dianhydrides, alicyclic tetracarboxylic dianhydrides, and aliphatic tetracarboxylic dianhydrides. They can be used individually or in combination of two or more.

[0255] There are no particular limitations on the diamines used; examples include aromatic diamines, alicyclic diamines, and aliphatic diamines commonly used in the synthesis of polyimides. They can be used individually or in combination of two or more.

[0256] Furthermore, from the perspective of lower dielectric constant and lower dielectric loss tangent, at least one of the above-mentioned tetracarboxylic acids or their dianhydrides or diamines may have one or more functional groups selected from the group consisting of fluorine group, trifluoromethyl group, hydroxyl group, sulfone group, carbonyl group, heterocyclic group, long-chain alkyl group, allyl group, etc.

[0257] Additionally, the polyimide resin used as component (III) can also be a commercially available polyimide resin, such as Neoprim (registered trademark) C-3650 (manufactured by Mitsubishi Gas Chemical Co., Ltd., trade name), Neoprim C-3G30 (manufactured by Mitsubishi Gas Chemical Co., Ltd., trade name), Neoprim C-3450 (manufactured by Mitsubishi Gas Chemical Co., Ltd., trade name), Neoprim P500 (manufactured by Mitsubishi Gas Chemical Co., Ltd., trade name), BT (bismaleimide triazine) resin (manufactured by Mitsubishi Gas Chemical Co., Ltd.), JL-20 (manufactured by Shin Nippon Rikka Co., Ltd., trade name) (the varnish of these polyimide resins may contain silica), RIKACOAT SN20 manufactured by Shin Nippon Rikka Co., Ltd., and RIKACOAT PN20, Pyre-ML manufactured by IST Corporation, UPIA-AT, UPIA-ST, UPIA-NF, UPIA-LB manufactured by Ube Industries, PIX-1400, PIX-3400, PI2525, PI2610, HD-3000, AS-2600 manufactured by Hitachi Chemical, HPC-5000, HPC-5012, HPC-1000, HPC-5020, HPC-3010, HPC-6000, HPC-9000, HCI-7000, HCI-1000S, HCI-1200E, HCI-1300 manufactured by Showa Denko Corporation, BMI-2300 manufactured by Daiwa Chemical Industries, Ltd., and MIR-3000 manufactured by Shin Nippon Chemical Co., Ltd.

[0258] As a component (III), the polyphenylene ether resin can be any resin that falls under the category of polyphenylene ether resin and contains phenylene ether units as repeating structural units. Alternatively, it may contain other structural units besides phenylene ether units.

[0259] As a homopolymer containing phenylene ether units, there are no particular restrictions on whether the phenylene in the phenylene unit has substituents. Examples of substituents include: acryloyl groups such as ethyl, propyl, isopropyl, butyl, isobutyl, and tert-butyl; cyclic alkyl groups such as cyclohexyl; vinyl, allyl, isopropenyl, 1-butenyl, 1-pentenyl, p-vinylphenyl, p-isopropenylphenyl, m-vinylphenyl, m-isopropenylphenyl, o-vinylphenyl, o-isopropenylphenyl, p-vinylbenzyl, p-isopropenylbenzyl, m-vinylbenzyl, m-isopropenylbenzyl, o-vinylbenzyl, o-isopropenylbenzyl, p-vinylphenylvinyl, p-vinylphenylpropenyl, p-vinylphenylbutenyl, m-vinylphenylvinyl, m-vinylphenylpropenyl, m-vinylphenylbutenyl, o-vinylphenylvinyl. Substituents containing unsaturated bonds, such as hydroxyl, carboxyl, carbonyl, thiocarbonyl, acyl halide, anhydride, carboxylic acid, thiocarboxylic acid, aldehyde, thioaldehyde, carboxylic acid ester, amide, sulfonic acid, sulfonate, phosphoric acid, phosphate, amino, imino, nitrile, pyridyl, quinolinyl, epoxy, thioepoxy, thioether, isocyanate, isothiocyanate, silicon halide, silanol, alkoxysilyl, tin halide, borate, boron-containing, borate, alkoxytin, and phenyltin. From the perspective of curability, for the purpose of free radical reactivity and / or reactivity with component (IV) curing agent, it is preferable to have any polar groups.

[0260] From the perspective of the curability of the resin composition of this embodiment, the molecular weight of the polyphenylene ether resin as component (III) is preferably 100,000 or less, more preferably 50,000 or less, and even more preferably 10,000 or less. In addition, the polyphenylene ether resin can be linear, cross-linked, or branched.

[0261] The liquid crystal polyester resin used as component (III) is any polyester that forms an anisotropic molten phase, as long as it falls within the category of liquid crystal polyester resin.

[0262] Examples include Eastman Kodak's "X7G", Darko's Xydar, Sumitomo Chemical's EKONOL, and Celanese's Vectra.

[0263] As a component (III), the fluorinated resin can be any fluoropolymer that falls under the category of fluoropolymers and is an olefin polymer containing fluorine groups.

[0264] Examples of the aforementioned fluorinated resins include polytetrafluoroethylene, perfluoroalkoxyalkane, ethylene-tetrafluoroethylene copolymer, perfluoroethylene-propylene copolymer, polyvinylidene fluoride, polychlorotrifluoroethylene, and ethylene-chlorotrifluoroethylene copolymer.

[0265] As a component (III), the epoxy resin can be any resin that falls under the category of epoxy resin, and from the perspective of strength, it is preferable to have two or more epoxy groups in one molecule.

[0266] Epoxy resin can be used alone or in combination of two or more types.

[0267] Examples of epoxy resins include: bixylenol-type epoxy resin, bisphenol A-type epoxy resin, bisphenol F-type epoxy resin, bisphenol S-type epoxy resin, bisphenol AF-type epoxy resin, dicyclopentadiene-type epoxy resin, triphenol-type epoxy resin, naphthol phenolic varnish-type epoxy resin, phenol phenolic varnish-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 phenolic varnish-type epoxy resin, biphenyl-type epoxy resin, alicyclic epoxy resin, heterocyclic epoxy resin, spirocyclic epoxy resin, cyclohexane-type epoxy resin, cyclohexanediol-type epoxy resin, naphthylene ether-type epoxy resin, tris(hydroxymethyl)-type epoxy resin, tetraphenylethane-type epoxy resin, etc.

[0268] Furthermore, from a reactivity perspective, when using epoxy resin as component (III), it is preferable to also include component (IV) curing agent. In this case, the polar groups of component (IV) curing agent can be, for example, carboxyl, imidazole, hydroxyl, amino, thiol, benzoxazine, and carbodiimide. From a reactivity perspective, carboxyl, imidazole, hydroxyl, benzoxazine, and carbodiimide are preferred. From a dielectric property perspective, hydroxyl, carboxyl, imidazole, benzoxazine, and carbodiimide are more preferred, and hydroxyl, carboxyl, and carbodiimide are even more preferred.

[0269] Furthermore, when using two or more polar resins with different free radical reactivity as component (III), from the perspective of curability, it is preferable to use a combination of component (II): free radical initiator and component (IV): curing agent. For example, when using maleimide-type polyimide resin with excellent free radical reactivity and bisphenol A epoxy resin without free radical reactivity as component (III), from the perspective of curability, it is preferable to add the aforementioned free radical initiator (II) and the aforementioned curing agent (IV).

[0270] Furthermore, when using a high-melting-point and high-rigidity polar resin as component (III): polar resin, the resin composition of this embodiment may not contain component (IV). Examples of high-melting-point and high-rigidity resins as component (III) include, for example, liquid crystal polyester resins, fluorinated resins such as polytetrafluoroethylene.

[0271] By making component (III) have a high melting point and high rigidity, it tends to have the strength required for practical use, even without component (IV).

[0272] (Ingredient (V): Additives)

[0273] The resin composition of this embodiment may further include various additives such as curing accelerators, fillers, and flame retardants as components (V).

[0274] Furthermore, the substances included in the additives of the block copolymer as component (I) have the same meaning as the components (V) of the above-mentioned resin composition.

[0275] Curing accelerators are added to promote the reactivity between the above components, and existing known curing accelerators can be used. Examples include phosphorus-based curing accelerators, amine-based curing accelerators, imidazole-based curing accelerators, guanidine-based curing accelerators, and metal-based curing accelerators.

[0276] Curing accelerators can be used alone or in combination of two or more.

[0277] Examples of phosphorus-based curing accelerators include, but are not limited to, triphenylphosphine, phosphorium borate compounds, tetraphenylboron tetraphenylphosphine, n-butylphosphonium tetraphenylboronate, tetrabutylphosphonium decanoate, (4-methylphenyl)triphenylphosphonium thiocyanate, tetraphenylphosphonium thiocyanate, and butyltriphenylphosphonium thiocyanate, with triphenylphosphine and tetrabutylphosphonium decanoate being preferred.

[0278] Examples of amine-based curing accelerators include, but are not limited to, trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine, benzyl dimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, and 1,8-diazabicyclo(5,4,0)-undecene, with 4-dimethylaminopyridine and 1,8-diazabicyclo(5,4,0)-undecene being preferred.

[0279] Examples of imidazole-based curing accelerators include, but are not limited to, 2-methylimidazolium, 2-undecylimidazolium, 2-heptadecylimidazolium, 1,2-dimethylimidazolium, 2-ethyl-4-methylimidazolium, 1,2-dimethylimidazolium, 2-ethyl-4-methylimidazolium, 2-phenylimidazolium, 2-phenyl-4-methylimidazolium, 1-benzyl-2-methylimidazolium, 1-benzyl-2-phenylimidazolium, 1-cyanoethyl-2-methylimidazolium, 1-cyanoethyl-2-undecylimidazolium, 1-cyanoethyl-2-ethyl-4-methylimidazolium, 1-cyanoethyl-2-phenylimidazolium, 1-cyanoethyl-2-undecylimidazolium oniumized trimellitate, 1-cyanoethyl-2-phenylimidazolium oniumized trimellitate, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-triazine, 2,4- Diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-triazine isocyanuric acid adduct, 2-phenylimidazolyl isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazolium, 2-phenyl-4-methyl-5-hydroxymethylimidazolium, 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazoline, 2-phenylimidazoline and other imidazole compounds and adducts of imidazole compounds with epoxy resins, preferably 2-ethyl-4-methylimidazolium and 1-benzyl-2-phenylimidazolium.

[0280] As an imidazole-based curing accelerator, commercially available products can be used, such as P200-H50 manufactured by Mitsubishi Chemical Corporation.

[0281] Examples of guanidine-based curing accelerators include, but are not limited to, 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]dec-5-ene, 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene, 1-methylbiguanidine, 1-ethylbiguanidine, 1-n-butylbiguanidine, 1-n-octadecylbiguanidine, 1,1-dimethylbiguanidine, 1,1-diethylbiguanidine, 1-cyclohexylbiguanidine, 1-allylbiguanidine, 1-phenylbiguanidine, and 1-(o-tolyl)biguanidine, with dicyandiamide and 1,5,7-triazabicyclo[4.4.0]dec-5-ene being preferred.

[0282] Examples of metal-based curing accelerators include, but are not limited to, organometallic complexes or organometallic salts of metals such as cobalt, copper, zinc, iron, nickel, manganese, and tin.

[0283] Specific examples of organometallic complexes include organocobalt complexes such as cobalt(II) acetylacetone and cobalt(III) acetylacetone, organocopper complexes such as copper(II) acetylacetone, organozinc complexes such as zinc(II) acetylacetone, organoiron complexes such as iron(III) acetylacetone, organonickel complexes such as nickel(II) acetylacetone, and organomanganese complexes such as manganese(II) acetylacetone.

[0284] Specific examples of organometallic salts include zinc octoate, tin octoate, zinc naphthenate, cobalt naphthenate, tin stearate, and zinc stearate.

[0285] Examples of fillers include, but are not limited to: inorganic fillers such as silicon dioxide, calcium carbonate, magnesium carbonate, magnesium hydroxide, aluminum hydroxide, calcium sulfate, barium sulfate, carbon black, glass fiber, glass beads, hollow glass spheres, glass flakes, graphite, titanium dioxide, potassium titanate whiskers, carbon fiber, alumina, kaolin, silica, calcium silicate, quartz, mica, talc, clay, zirconium oxide, potassium titanate, alumina, and metal particles; and organic fillers such as wood chips, wood powder, pulp, and cellulose nanofibers.

[0286] These fillers can be used individually or in combination of multiple types.

[0287] The shape of these fillers can be any of the following: flakes, spheres, granules, powders, amorphous shapes, etc., without any particular limitation.

[0288] In this embodiment, the resin composition or cured product is often exposed to high temperatures during molding. To prevent shrinkage and deformation of the molded body due to temperature changes, the filler preferably has a low coefficient of linear expansion. From the perspective of reducing the coefficient of linear expansion, silica is preferred as the filler. Examples of silica include amorphous silica, molten silica, crystalline silica, synthetic silica, and hollow silica.

[0289] Flame retardants include, but are not limited to, halogenated flame retardants such as bromine compounds, phosphorus-based flame retardants such as aromatic compounds, metal hydroxides, alkyl sulfonates, antimony trioxide, aluminum hydroxide, magnesium hydroxide, zinc borate, hexabromobenzene, decabromodiphenyl ethane, 4,4-dibromobiphenyl, ethylenebistetrabromophthalimide, and other flame retardants containing aromatic bromine compounds.

[0290] These flame retardants can be used alone or in combination of two or more.

[0291] The aforementioned flame retardants also include so-called flame retardant additives, which, although their own flame retardant performance is low, can synergistically exert a better effect when used in combination with other flame retardants.

[0292] Fillers and flame retardants can also be of the type that have been pre-treated with surface treatment agents such as silane coupling agents.

[0293] Examples of surface treatment agents include, but are not limited to, fluorinated silane coupling agents, aminosilane coupling agents, epoxysilane coupling agents, mercaptosilane coupling agents, silane coupling agents, alkoxysilanes, organosilazane compounds, and titanate coupling agents. They can be used individually or in combination.

[0294] There are no particular restrictions on other additives, as long as they are commonly used in the formulation of resin compositions and / or cured products.

[0295] Other additives include, but are not limited to: pigments and / or colorants such as carbon black and titanium dioxide; lubricants such as stearic acid, behenic acid, zinc stearate, calcium stearate, magnesium stearate, and ethylene bis-stearamide; anti-sticking agents; plasticizers such as organopolysiloxanes, phthalate or adipate compounds, azelaic acid ester compounds, and mineral oils; antioxidants such as hindered phenolic and phosphorus-based heat stabilizers; hindered amine light stabilizers; benzotriazole ultraviolet absorbers; antistatic agents; organic fillers; thickeners; defoamers; leveling agents; and resin additives such as adhesion promoters; other additives or mixtures thereof.

[0296] From the perspectives of lower dielectric constant and lower dielectric loss tangent, it is preferable that the resin composition of this embodiment does not contain pigments, colorants, lubricants, anti-sticking agents, or antistatic agents.

[0297] The resin composition in this embodiment can be a substance formed by melting and mixing the components, or it can be a substance formed by dissolving the components in a soluble solvent and stirring (hereinafter referred to as "varnish"). From the perspective of processability, varnish is preferred.

[0298] Examples of solvents include, but are not limited to: ketones such as acetone, methyl ethyl ketone (MEK), cyclohexanone, and γ-butyrolactone; acetates such as ethyl acetate, butyl acetate, acetic acid cellosolve, propylene glycol monomethyl ether acetate, carbitol acetate, and diethylene glycol monoethyl ether acetate; carbitols such as cellosolve and butyl carbitol; aromatic hydrocarbons such as toluene and xylene; and amide solvents such as dimethylformamide, dimethylacetamide (DMAc), and N-methylpyrrolidone. Organic solvents can be used alone or in combination of two or more.

[0299] [cured material]

[0300] The cured product of this embodiment includes the block copolymer described in this embodiment.

[0301] Furthermore, the cured product of this embodiment is obtained by subjecting the resin composition of this embodiment to a curing reaction at any temperature and time. This includes not only fully cured products, but also products where only a portion of the resin composition is cured, thus containing uncured components (semi-cured products).

[0302] In the manufacturing process of the laminates described later, a process for further curing of the cured material may also be performed.

[0303] The reaction temperature of the curing process of the cured product in this embodiment is preferably 80°C or higher, more preferably 100°C or higher, and even more preferably 120°C or higher. The reaction time is preferably 10 to 240 minutes, more preferably 20 to 230 minutes, and even more preferably 30 to 220 minutes. When the resin composition in this embodiment is a varnish, the curing reaction is preferably carried out after the solvent is removed. As a drying method, it can be carried out by existing known methods such as heating or hot air blowing, preferably at a temperature lower than the curing reaction temperature. Regarding the amount of solvent in the resin composition, it is preferably dried to 10% by mass or less, more preferably to 5% by mass or less.

[0304] [Resin film]

[0305] The resin film of this embodiment is composed of the resin composition of this embodiment.

[0306] The resin film of this embodiment is obtained by spreading a varnish composed of the resin composition of this embodiment into a uniform thin film on a suitable support, and then drying it as described above to remove the solvent. This resin film can be rolled up and stored.

[0307] The resin film in this embodiment may be composed of a layered protective film, in which case it can be used by peeling off the protective film.

[0308] Examples of supporting materials include films made of plastic materials, metal foils, and release paper.

[0309] The membrane made of plastic material that serves as the support can be, but is not limited to, polyesters such as polyethylene terephthalate and polyethylene naphthalate; acrylics such as polycarbonate and polymethyl methacrylate (PMMA); cyclic polyolefins, triacetyl cellulose (TAC), polyether sulfide (PES), polyether ketone, and polyimide. From the perspectives of availability and cost, polyethylene terephthalate and polyethylene naphthalate are preferred.

[0310] Examples of metal foils include, but are not limited to, copper foil and aluminum foil, with copper foil being preferred. Copper foil can be used as the metal foil, either as a single metal such as copper or as an alloy of copper with other metals such as tin, chromium, silver, magnesium, nickel, zirconium, silicon, titanium, etc.

[0311] In addition, the support can also be roughened, corona treated, antistatic treated, and anti-stick treated on the surface that bonds with the resin composition layer.

[0312] [Prepreg]

[0313] The prepreg of this embodiment comprises a substrate and a resin composition of this embodiment impregnated or coated onto the substrate. That is, the prepreg of this embodiment is a composite of the resin composition of this embodiment and the substrate.

[0314] The prepreg is obtained, for example, by impregnating a substrate such as glass cloth into a varnish that is the resin composition of the present embodiment described above, and then removing the solvent by the drying method described above.

[0315] Examples of suitable substrates include, but are not limited to: various glass cloths such as roving, cloth, chopped strand mat, and surface felt; asbestos cloth, metal fiber cloth, and other synthetic or natural inorganic fiber cloths; woven or nonwoven fabrics made from liquid crystal fibers such as fully aromatic polyamide fibers, fully aromatic polyester fibers, and polybenzoxazole fibers; natural fiber cloths such as cotton cloth, linen cloth, and felt; natural cellulose-based substrates such as carbon fiber cloth, kraft paper, cotton paper, and cloths made from paper-glass blended fibers; and polytetrafluoroethylene porous membranes. From the perspective of dielectric properties, glass cloth is preferred.

[0316] These substrates can be used alone or in combination of two or more.

[0317] The proportion of solid components in the prepreg, which are composed of the resin composition of this embodiment, is preferably 30 to 80% by mass, more preferably 40 to 70% by mass. When the above proportion is 30% by mass or more, the prepreg tends to have superior insulation reliability when used for applications such as electronic substrates. When the above proportion is 80% by mass or less, the prepreg tends to have superior mechanical properties such as rigidity when used for applications such as electronic substrates.

[0318] [laminated body]

[0319] The laminate of this embodiment includes the resin film and metal foil described above. Additionally, the laminate of this embodiment includes the cured prepreg and metal foil described above.

[0320] The laminate of this embodiment can be manufactured, for example, by the following steps: a step (a) of depositing a resin film composed of the resin composition of this embodiment on a substrate to form a resin layer and obtaining a prepreg; a step (b) of heating and pressurizing the resin layer to planarize it and obtaining a cured prepreg; and a step (c) of further forming a predetermined wiring layer composed of metal foil on the resin layer; and so on.

[0321] In step (a), the method for laminating the resin film onto the substrate is not particularly limited. Examples include multi-stage presses, vacuum presses, atmospheric pressure laminators, and laminators that use heat and pressure under vacuum. The method using a heat and pressure laminator under vacuum is preferred. In this method, even if the target electronic circuit board has fine wiring circuits on its surface, the resin can be embedded between the circuits without gaps. Furthermore, lamination can be done in batches or continuously using rollers or the like.

[0322] Examples of substrates that can be used as substrates include, but are not limited to, various substrates constituting the prepreg described above, such as glass epoxy boards, metal substrates, polyester substrates, polyimide substrates, polyphenylene ether substrates, and fluoropolymer substrates. The surfaces of the laminated resin layers of the substrate can be pre-roughened, and the number of substrate layers is not limited.

[0323] In step (b) above, the resin film and substrate laminated in step (a) are planarized under heat and pressure. The conditions can be adjusted arbitrarily according to the type of substrate and the composition of the resin film. For example, the preferred temperature range is 100-300°C, pressure is 0.2-20 MPa, and time is 30-180 minutes.

[0324] In step (c) above, the resin film and the substrate are heated and pressurized to further form a predetermined wiring layer composed of metal foil on the formed resin layer. There are no particular limitations on the formation method; existing known methods can be cited, such as subtractive etching methods and semi-additive methods.

[0325] The subtractive method is as follows: a resist layer corresponding to the desired pattern shape is formed on a metal layer, and then the portion of the metal layer to which the resist has been removed is dissolved and removed by a reagent through a subsequent development process, thereby forming the desired wiring.

[0326] The semi-addition method is as follows: a metal coating is formed on the surface of the resin layer by electroless plating, a resist layer with a shape corresponding to the desired pattern is formed on the metal coating, and then the metal layer is formed by electroplating. The unwanted electroless plating layer is removed by reagents, etc., to form the desired wiring layer.

[0327] Furthermore, pores such as vias can be formed in the resin layer as needed. There are no particular limitations on the method for forming these pores; existing known methods can be used. Examples of methods for forming pores include NC drill bits, carbon dioxide lasers, UV lasers, YAG lasers, and plasma.

[0328] Metal-coated laminate

[0329] The laminate described in this embodiment can be plate-shaped or flexible laminate.

[0330] The laminate in this embodiment can be a metal-clad laminate.

[0331] The metal-clad laminate is obtained by laminating and curing the resin composition of this embodiment or the prepreg of this embodiment with a metal foil, and a portion of the metal foil is removed from the metal-clad laminate.

[0332] Metal-clad laminates preferably have a form in which a cured prepreg (also known as a "cured composite") and a metal foil are laminated and bonded together, making them suitable as materials for use as electronic circuit boards.

[0333] Examples of metal foils include, but are not limited to, aluminum foil and copper foil, with copper foil being preferred due to its low resistance.

[0334] The cured prepreg combined with metal foil can be a single sheet or multiple sheets, with metal foils overlapped on one or both sides of the cured material and processed into a laminate, depending on the application.

[0335] As a method for manufacturing the above-mentioned laminate, one example is the following method: forming a prepreg composed of the resin composition of this embodiment and a substrate, overlapping it with a metal foil, and then curing the resin composition, thereby obtaining a laminate in which the cured prepreg and the metal foil are laminated.

[0336] One particularly preferred application of the aforementioned laminate is in printed circuit boards. Printed circuit boards preferably have at least a portion of the metal foil removed from the metal-clad laminate.

[0337] The aforementioned printed circuit board can be manufactured using a pressure heating molding method with the prepreg described in this embodiment. The same substrate as described above for the prepreg can be used as the substrate. The aforementioned printed circuit board, containing the resin composition of this embodiment, exhibits excellent strength and electrical properties (low dielectric constant and low dielectric loss tangent), thereby suppressing variations in electrical properties due to environmental changes, and possessing excellent insulation reliability and mechanical properties.

[0338] Materials used for electronic circuit boards

[0339] The material used for the electronic circuit board in this embodiment includes a cured product of the resin composition of this embodiment.

[0340] The electronic circuit board used in this embodiment can be made using the resin composition and / or varnish described in this embodiment.

[0341] The material used for the electronic circuit board of this embodiment includes at least one selected from the group consisting of a cured product of the above-described resin composition, a resin film containing the resin composition of this embodiment or a cured product thereof, and a composite prepreg of a substrate and a resin composition. The material used for the electronic circuit board of this embodiment can be used as a printed circuit board having a resin-coated metal foil.

[0342] Example

[0343] The following specific embodiments and comparative examples illustrate this implementation method in detail, but the present invention is not limited to the following embodiments and comparative examples.

[0344] It should be noted that the methods for structural identification and property determination of the block copolymers (component (I)) used in the following examples and comparative examples are as follows.

[0345] [Methods for polymer structure identification and property determination]

[0346] ((1) Content of vinyl aromatic monomer units in block copolymers)

[0347] Using the unhydrogenated block copolymer, the content of vinyl aromatic monomer units in the block copolymer was determined using a UV spectrophotometer (Shimadzu Corporation, UV-2450).

[0348] ((2) Vinyl bond content of block copolymer)

[0349] The amount of vinyl bonding was determined using an infrared spectrophotometer (FT / IR-230, manufactured by Nippon Spectrophotometer Co., Ltd.) using the unhydrogenated block copolymer.

[0350] The amount of vinyl bonds in the block copolymer was calculated using the Hampton method.

[0351] This value is taken as the content of units (a) derived from 1,2-bonded and / or 3,4-bonded when the total content of polymer blocks (B) and / or polymer blocks (C) of the block copolymer of component (I) is 100%.

[0352] (3) Molecular weight and molecular weight distribution of block copolymers)

[0353] The molecular weight of the (I) block copolymer before modification and hydrogenation was determined using GPC [Apparatus: LC-10 (Shimadzu Corporation), Column: TSKgel GMHXL (4.6 mm × 30 cm)].

[0354] Tetrahydrofuran was used as the solvent. The determination was performed at 35°C.

[0355] The molecular weight is the weight-average molecular weight obtained by determining the molecular weight of the peaks in the chromatogram using a calibration curve (made using the peak molecular weight of standard polystyrene) derived from the determination of commercially available standard polystyrene.

[0356] It should be noted that when there are multiple peaks in a chromatogram, the molecular weight is the average molecular weight calculated from the molecular weight of each peak and the composition ratio of each peak (which is determined by the area ratio of each peak in the chromatogram).

[0357] In addition, the molecular weight distribution is the ratio of the obtained weight-average molecular weight (Mw) to the number-average molecular weight (Mn) (Mw / Mn).

[0358] (4) Hydrogenation rate of double bonds in the conjugated diene monomer units of the block copolymer)

[0359] Using the hydrogenated component (I) block copolymer, the hydrogenation rate of the double bonds in the conjugated diene monomer units was determined using a nuclear magnetic resonance apparatus (BRUKER DPX-400).

[0360] [Materials for block copolymers and resin compositions]

[0361] (Preparation of hydrogenation catalyst)

[0362] In the examples and comparative examples described below, the hydrogenation catalyst used in the production of block copolymers was prepared by the following method.

[0363] The reaction vessel equipped with a stirring device was purged with nitrogen, and 1 liter of dried and purified cyclohexane was added into it.

[0364] Next, 100 mmol of bis(η5-cyclopentadiene)titanium dichloride was added. While stirring thoroughly, a hexane solution containing 200 mmol of trimethylaluminum was added, and the reaction was carried out at room temperature for about 3 days. This yielded the hydrogenation catalyst.

[0365] (Component (I): Block copolymer)

[0366] Block copolymers of vinyl aromatic compounds and conjugated dienes are prepared as follows.

[0367] The structure and physical properties of each block copolymer are shown in Tables 1 and 2.

[0368] It should be noted that in the table, (A) represents a polymer block (A) mainly composed of vinyl aromatic monomer units, (B) represents a polymer block (B) mainly composed of conjugated diene monomer units, and (C) represents a polymer block (C) composed of vinyl aromatic monomer units and conjugated diene monomer units.

[0369] <block copolymer(1)>

[0370] Batch polymerization was carried out using a tank reactor (10L internal volume) equipped with a stirring device and a jacket.

[0371] First, a cyclohexane solution (20% by mass) containing 37.5 parts by mass of styrene is added to the above-mentioned tank reactor.

[0372] Next, 0.23 parts by mass of n-butyllithium relative to 100 parts by mass of all monomers and 0.8 mol of tetramethylethylenediamine (TMEDA) relative to 1 mol of n-butyllithium were added, and polymerization was carried out at 70°C for 45 minutes.

[0373] Next, a cyclohexane solution containing 25 parts by mass of butadiene (concentration 20% by mass) was added, and polymerization was carried out at 70°C for 20 minutes.

[0374] Next, a cyclohexane solution containing 37.5 parts by mass of styrene (20% by mass) was added, and polymerization was carried out for 45 minutes. Then, methanol was added to stop the polymerization reaction, yielding a block copolymer.

[0375] The block copolymer obtained as described above has a styrene content of 75% by mass and a weight-average molecular weight of 3.0 × 10⁻⁶. 4 The molecular weight distribution is 1.10, and the content of units (a) derived from 1,2-bonding and / or 3,4-bonding (vinyl bond content: unit (a) / polymer block (B)) is 70%.

[0376] <block copolymer (2)>

[0377] The polymerization reaction was carried out in the same manner as the block copolymer (1) described above, except that 0.36 parts by mass of n-butyllithium was added relative to 100 parts by mass of all monomers.

[0378] The block copolymer obtained as described above has a styrene content of 75% by mass and a weight-average molecular weight of 2.1 × 10⁻⁶. 4 The molecular weight distribution is 1.10, and the content of units (a) derived from 1,2-bonding and / or 3,4-bonding (vinyl bond content: unit (a) / polymer block (B)) is 70%.

[0379] <block copolymer (3)>

[0380] Add 0.65 parts by weight of n-butyllithium relative to 100 parts by weight of all monomers, and 1.2 mol of tetramethylethylenediamine (TMEDA) relative to 1 mol of n-butyllithium, and otherwise carry out the same operation as the block copolymer (1) above to carry out the polymerization reaction.

[0381] The block copolymer obtained as described above has a styrene content of 75% by mass and a weight-average molecular weight of 1.0 × 10⁻⁶. 4 The molecular weight distribution is 1.10, and the content of units (a) derived from 1,2-bonding and / or 3,4-bonding (vinyl bond content: unit (a) / polymer block (B)) is 71%.

[0382] <block copolymer (4)>

[0383] The polymerization reaction was carried out by adding 1.42 parts by mass of n-butyllithium relative to 100 parts by mass of all monomers, and otherwise proceeding in the same manner as the block copolymer (3) described above.

[0384] The block copolymer obtained as described above has a styrene content of 75% by mass and a weight-average molecular weight of 0.5 × 10⁻⁶. 4 The molecular weight distribution is 1.10, and the content of units (a) derived from 1,2-bonding and / or 3,4-bonding (vinyl bond content: unit (a) / polymer block (B)) is 69%.

[0385] <block copolymer (5)>

[0386] The polymerization reaction was carried out by adding 3.20 parts by mass of n-butyllithium relative to 100 parts by mass of all monomers, and otherwise proceeding in the same manner as the block copolymer (3) described above.

[0387] The block copolymer (5) obtained as described above has a styrene content of 75% by mass and a weight-average molecular weight of 0.2 × 10⁻⁶. 4 The molecular weight distribution is 1.10, and the content of units (a) derived from 1,2-bonding and / or 3,4-bonding (vinyl bond content: unit (a) / polymer block (B)) is 70%.

[0388] <block copolymer (6)>

[0389] Batch polymerization was carried out using a tank reactor (10L internal volume) equipped with a stirring device and a jacket.

[0390] First, a cyclohexane solution (20% by mass) containing 27.5 parts by mass of styrene is added to the above-mentioned tank reactor.

[0391] Next, 1.42 parts by mass of n-butyllithium relative to 100 parts by mass of all monomers and 1.2 mol of tetramethylethylenediamine (TMEDA) relative to 1 mol of n-butyllithium were added, and polymerization was carried out at 70°C for 45 minutes.

[0392] Next, a cyclohexane solution containing 45 parts by mass of butadiene (concentration 20% by mass) was added, and polymerization was carried out at 70°C for 20 minutes.

[0393] Next, a cyclohexane solution containing 27.5 parts by mass of styrene (20% by mass) was added, and polymerization was carried out for 45 minutes. Then, methanol was added to stop the polymerization reaction, yielding a block copolymer.

[0394] The block copolymer (6) obtained as described above has a styrene content of 55% by mass and a weight-average molecular weight of 0.5 × 10⁻⁶. 4 The molecular weight distribution is 1.10, and the content of units (a) derived from 1,2-bonding and / or 3,4-bonding (vinyl bond content: unit (a) / polymer block (B)) is 69%.

[0395] <block copolymer (7)>

[0396] Batch polymerization was carried out using a tank reactor (10L internal volume) equipped with a stirring device and a jacket.

[0397] First, a cyclohexane solution containing 45 parts by mass of styrene (concentration 20% by mass) is added to the above-mentioned tank reactor.

[0398] Next, 1.42 parts by mass of n-butyllithium relative to 100 parts by mass of all monomers and 1.2 mol of tetramethylethylenediamine (TMEDA) relative to 1 mol of n-butyllithium were added, and polymerization was carried out at 70°C for 45 minutes.

[0399] Next, a cyclohexane solution containing 10 parts by mass of butadiene (concentration 20% by mass) was added, and polymerization was carried out at 70°C for 20 minutes.

[0400] Next, a cyclohexane solution containing 45 parts by mass of styrene (20% by mass) was added, and polymerization was carried out for 45 minutes. Then, methanol was added to stop the polymerization reaction, yielding a block copolymer.

[0401] The block copolymer (7) obtained as described above has a styrene content of 90% by mass and a weight-average molecular weight of 0.5 × 10⁻⁶. 4 The molecular weight distribution is 1.10, and the content of units (a) derived from 1,2-bonding and / or 3,4-bonding (vinyl bond content: unit (a) / polymer block (B)) is 70%.

[0402] <block copolymer (8)>

[0403] The polymerization reaction was carried out by adding 0.1 mol of TMEDA to 1 mol of n-butyllithium, otherwise the same operation as the block copolymer (4) was performed.

[0404] The block copolymer (8) obtained as described above has a styrene content of 75% by mass and a weight-average molecular weight of 0.5 × 10⁻⁶. 4 The molecular weight distribution is 1.10, and the content of units (a) derived from 1,2-bonding and / or 3,4-bonding (vinyl bond content: unit (a) / polymer block (B)) is 31%.

[0405] <block copolymer (9)>

[0406] Add 0.1 mol of TMEDA to 1 mol of n-butyllithium, extend the polymerization time of each block by 5 minutes, and otherwise perform the same operation as the block copolymer (8) above to carry out the polymerization reaction.

[0407] The block copolymer (9) obtained as described above has a styrene content of 75% by mass and a weight-average molecular weight of 0.5 × 10⁻⁶. 4 The molecular weight distribution is 1.10, and the content of units (a) derived from 1,2-bonding and / or 3,4-bonding (vinyl bond content: unit (a) / polymer block (B)) is 16%.

[0408] <Hydrogenated block copolymer (10)>

[0409] The same polymerization operation as that for the block copolymer (4) was performed. Then, the hydrogenation catalyst prepared as described above was added to the obtained block copolymer at a concentration of 90 ppm relative to Ti per 100 parts by mass of the block copolymer, and the hydrogenation reaction was carried out at a hydrogen pressure of 0.7 MPa and a temperature of 80 °C for about 0.15 hours to obtain the hydrogenated block copolymer (10).

[0410] The hydrogenated block copolymer (10) obtained as described above has a styrene content of 75% by mass and a weight-average molecular weight of 0.5 × 10⁻⁶. 4 The molecular weight distribution is 1.10, the content of units (a) derived from 1,2-bonding and / or 3,4-bonding (vinyl bond content: unit (a) / polymer block (B)) is 70%, and the hydrogenation rate is 22%.

[0411] <Hydrogenated block copolymer (11)>

[0412] A hydrogenation reaction was carried out for 0.35 hours, and then the same operation as the above-mentioned hydrogenated block copolymer (10) was performed to obtain hydrogenated block copolymer (11).

[0413] The hydrogenated block copolymer (11) obtained as described above has a styrene content of 75% by mass and a weight-average molecular weight of 0.5 × 10⁻⁶. 4 The molecular weight distribution is 1.10, the content of units (a) derived from 1,2-bonding and / or 3,4-bonding (vinyl bond content: unit (a) / polymer block (B)) is 69%, and the hydrogenation rate is 51%.

[0414] <Hydrogenated block copolymer (12)>

[0415] A hydrogenation reaction was carried out for 0.75 hours, and otherwise the same operation as the above-mentioned hydrogenated block copolymer (10) was performed to obtain hydrogenated block copolymer (12).

[0416] The hydrogenated block copolymer (12) obtained as described above has a styrene content of 75% by mass and a weight-average molecular weight of 0.5 × 10⁻⁶. 4 The molecular weight distribution is 1.10, the content of units (a) derived from 1,2-bonding and / or 3,4-bonding (vinyl bond content: unit (a) / polymer block (B)) is 71%, and the hydrogenation rate is 72%.

[0417] <Block copolymer (13)>

[0418] Batch polymerization was carried out using a tank reactor (10L internal volume) equipped with a stirring device and a jacket.

[0419] First, a cyclohexane solution containing 30 parts by mass of styrene (concentration 20% by mass) is added to the above-mentioned tank reactor.

[0420] Next, 1.42 parts by mass of n-butyllithium relative to 100 parts by mass of all monomers and 1.2 mol of tetramethylethylenediamine (TMEDA) relative to 1 mol of n-butyllithium were added, and polymerization was carried out at 70°C for 25 minutes.

[0421] Next, a cyclohexane solution (20% by mass) containing 15 parts by mass of styrene and 25 parts by mass of butadiene was added, and polymerization was carried out at 70°C for 35 minutes.

[0422] Next, a cyclohexane solution containing 30 parts by mass of styrene (20% by mass) was added, and polymerization was carried out for 25 minutes. Then, methanol was added to stop the polymerization reaction, yielding a block copolymer (13).

[0423] The block copolymer (13) obtained as described above has a styrene content of 75% by mass and a weight-average molecular weight of 0.5 × 10⁻⁶. 4 The molecular weight distribution is 1.10, and the content of unit (a) derived from 1,2-bonding and / or 3,4-bonding (vinyl bond amount: unit (a) / conjugated diene monomer unit amount in polymer block (C)) is 69%.

[0424] <block copolymer (14)>

[0425] 2.0 mol TMEDA was added relative to n-butyllithium, the reaction temperature was set to 50°C, and the reaction time of each block was extended by 20 minutes. Otherwise, the same procedure as for block copolymer (3) was performed to obtain block copolymer (14). The obtained block copolymer (14) had a styrene content of 75% by mass and a weight-average molecular weight of 1.0 × 10⁻⁶. 4 The molecular weight distribution is 1.13, and the content of units (a) derived from 1,2-bonding and / or 3,4-bonding (vinyl bond content: unit (a) / polymer block (B)) is 88%.

[0426] <Block copolymer (15)>

[0427] Batch polymerization was carried out using a tank reactor (10L internal volume) equipped with a stirring device and a jacket.

[0428] First, add a cyclohexane solution containing 25 parts by mass of styrene (concentration 20% by mass).

[0429] Next, 0.45 parts by mass of n-butyllithium relative to 100 parts by mass of all monomers and 0.8 mol of tetramethylethylenediamine (TMEDA) relative to 1 mol of n-butyllithium were added, and polymerization was carried out at 70°C for 20 minutes.

[0430] Next, a cyclohexane solution (20% by mass) containing 50 parts by mass of styrene and 25 parts by mass of butadiene was added, and polymerization was carried out at 70°C for 30 minutes.

[0431] Methanol was then added to stop the polymerization reaction, yielding a block copolymer (15).

[0432] The block copolymer (15) obtained as described above has a styrene content of 75% by mass and a weight-average molecular weight of 1.5 × 10⁻⁶. 4 The molecular weight distribution is 1.10, and the content of unit (a) derived from 1,2-bonding and / or 3,4-bonding (vinyl bond content: unit (a) / conjugated diene monomer unit content in polymer block (C)) is 71%.

[0433] <block copolymer (16)>

[0434] Batch polymerization was carried out using a tank reactor (10L internal volume) equipped with a stirring device and a jacket.

[0435] First, a cyclohexane solution (20% by mass) containing 22.5 parts by mass of styrene is added to the above-mentioned tank reactor.

[0436] Next, 0.65 parts by mass of n-butyllithium relative to 100 parts by mass of all monomers and 1.2 mol of tetramethylethylenediamine (TMEDA) relative to 1 mol of n-butyllithium were added, and polymerization was carried out at 70°C for 15 minutes.

[0437] Next, a cyclohexane solution containing 55 parts by mass of butadiene (concentration 20% by mass) was added, and polymerization was carried out at 70°C for 30 minutes.

[0438] Next, a cyclohexane solution containing 22.5 parts by mass of styrene (20% by mass) was added, and polymerization was carried out for 20 minutes. Then, methanol was added to stop the polymerization reaction, yielding a block copolymer (16).

[0439] The block copolymer (16) obtained as described above has a styrene content of 45% by mass and a weight-average molecular weight of 1.0 × 10⁻⁶. 4 The molecular weight distribution is 1.10, and the content of units (a) derived from 1,2-bonding and / or 3,4-bonding (vinyl bond content: unit (a) / polymer block (B)) is 71%.

[0440] <block copolymer (17)>

[0441] The same operation as that for the block copolymer (3) was performed to make the n-butyllithium content 0.17 parts by mass relative to all 100 parts by mass of the monomers, and the block copolymer (17) was obtained.

[0442] The block copolymer (17) obtained as described above has a styrene content of 75% by mass and a weight-average molecular weight of 4.0 × 10⁻⁶. 4 The molecular weight distribution is 1.10, and the content of units (a) derived from 1,2-bonding and / or 3,4-bonding (vinyl bond content: unit (a) / polymer block (B)) is 71%.

[0443] <block copolymer (18)>

[0444] Batch polymerization was carried out using a tank reactor (10L internal volume) equipped with a stirring device and a jacket.

[0445] First, a cyclohexane solution containing 7.5 parts by mass of butadiene (concentration 20% by mass) is added to the above-mentioned tank reactor.

[0446] Next, 0.65 parts by mass of n-butyllithium relative to 100 parts by mass of all monomers and 1.2 mol of tetramethylethylenediamine (TMEDA) relative to 1 mol of n-butyllithium were added, and polymerization was carried out at 70°C for 5 minutes.

[0447] Next, a cyclohexane solution (20% by mass) containing 10 parts by mass of butadiene and 75 parts by mass of styrene was added, and polymerization was carried out at 70°C for 30 minutes.

[0448] Next, a cyclohexane solution containing 7.5 parts by mass of butadiene (20% by mass) was added, and polymerization was carried out for 5 minutes. Then, methanol was added to stop the polymerization reaction, yielding a block copolymer (18).

[0449] The block copolymer (18) obtained as described above has a styrene content of 75% by mass and a weight-average molecular weight of 1.0 × 10⁻⁶. 4 The molecular weight distribution is 1.10, and the content of unit (a) derived from 1,2-bonding and / or 3,4-bonding (vinyl bond amount: unit (a) / (conjugated diene monomer unit amount in polymer block (B) + polymer block (C))) is 70%.

[0450] <Block copolymer (19)>

[0451] Batch polymerization was carried out using a tank reactor (10L internal volume) equipped with a stirring device and a jacket.

[0452] First, a cyclohexane solution (concentration 20% by mass) containing 25 parts by mass of butadiene and 75 parts by mass of styrene is added to the above-mentioned tank reactor.

[0453] Next, 1.42 parts by mass of n-butyllithium relative to 100 parts by mass of all monomers and 1.2 mol of tetramethylethylenediamine (TMEDA) relative to 1 mol of n-butyllithium were added, and polymerization was carried out at 70°C for 60 minutes to obtain a block copolymer (19).

[0454] The block copolymer (19) obtained as described above has a styrene content of 75% by mass and a weight-average molecular weight of 1.0 × 10⁻⁶. 4 The molecular weight distribution is 1.10, and the content of unit (a) derived from 1,2-bonding and / or 3,4-bonding (vinyl bond amount: unit (a) / conjugated diene monomer unit amount in block (C)) is 70%.

[0455] (Component (II): Free radical initiator)

[0456] Perbutyl C (manufactured by NOF Corporation)

[0457] Percumyl D (manufactured by Nippon Oil Co., Ltd.)

[0458] (Component (III): Polar resin)

[0459] As a polar resin, the following polymers are polyphenylene ether resins (PPE).

[0460] 0.2512 g of copper chloride dihydrate, 1.1062 g of 35% hydrochloric acid, 3.6179 g of di-n-butylamine, 9.5937 g of N,N,N',N'-tetramethylpropanediamine, 211.63 g of methanol, and 493.80 g of n-butanol, along with 180.0 g of 2,6-dimethylphenol containing 5 mol% 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane, were added to a 1.5-liter jacketed reactor. The reactor was equipped with a nozzle for introducing oxygen-containing gas, stirring turbine blades, and baffles at the bottom, and a reflux cooler at the exhaust line at the top of the reactor.

[0461] The solvent used had a mass ratio of n-butanol:methanol = 70:30. Then, while stirring vigorously, oxygen was introduced into the reactor from the nozzle at a rate of 180 mL / min, while simultaneously adjusting the temperature by circulating a heat transfer medium through the jacket to maintain a polymerization temperature of 40°C.

[0462] The polymerization liquid gradually becomes a slurry.

[0463] When the polyphenylene ether reaches the desired number average molecular weight, the gas flow is stopped, and the resulting polymer mixture is heated to 50°C. Then, hydroquinone (a reagent manufactured by Wako Pure Chemicals Co., Ltd.) is added little by little, and the mixture is kept at 50°C until the slurry-like polyphenylene ether turns white.

[0464] Next, 720g of a methanol solution containing 6.5% by mass of 36% hydrochloric acid was added, filtered, and then repeatedly washed with methanol to obtain wet polyphenylene ether.

[0465] Next, the product was dried under vacuum at 100°C to obtain dried polyphenylene ether. The ηsp / c was 0.103 dL / g, and the yield was 97%.

[0466] In the determination of ηsp / c, the above-mentioned polyphenylene ether was prepared into a chloroform solution of 0.5 g / dL, and the specific viscosity (ηsp / c) at 30°C was determined using an Ubbelohde viscometer. The unit is dL / g.

[0467] The obtained polyphenylene ether was modified as follows.

[0468] 152.5 g of polyphenylene ether and 152.5 g of toluene were mixed and heated to approximately 85°C. Then, 2.1 g of dimethylaminopyridine was added. At the moment when the solid had completely dissolved, 18.28 g of methacrylic anhydride was slowly added. The resulting solution was continuously mixed while maintaining the temperature at 85°C for 3 hours. The solution was then cooled to room temperature to obtain a toluene solution of methacrylate-terminated polyphenylene ether. To the obtained toluene solution, 1000 mL of methanol at 10°C was added dropwise in a 3 L cylindrical SUS container equipped with a homogenizer and a stirrer. The resulting powder was filtered, washed with methanol, and dried under nitrogen at 85°C for 18 hours.

[0469] (Component (IV): Curing agent)

[0470] Triallyl isocyanurate (TAIC) TM (Manufactured by Mitsubishi Chemical Corporation)

[0471] [Methods for determining the physical properties of resin compositions]

[0472] ((1) Dielectric loss tangent and dielectric constant)

[0473] The dielectric loss tangent at 10 GHz was determined using the cavity resonance method.

[0474] As the measuring apparatus, a network analyzer (N5230A, manufactured by Agilent Technologies) and a cavity resonator (Cavity Resornator CP series) manufactured by Kanto Electronics Application Development Co., Ltd. were used.

[0475] Regarding the test sample, a test piece measuring 2.6 mm wide and 80 mm long was cut from the cured film (described later) and used as the test sample.

[0476] Using the dielectric loss tangent and dielectric constant obtained above, the following examples and comparative examples were evaluated according to the following criteria.

[0477] Evaluation Criteria in (Examples 1-17) and (Comparative Examples 1-7)

[0478] Dielectric loss tangent

[0479] ◎: 0.004 or less

[0480] ○: 0.005 or less

[0481] △: less than 0.006

[0482] ×: 0.006 or more

[0483] Dielectric constant

[0484] ◎:2.23 or less

[0485] ○:2.27 or less

[0486] △: less than 2.30

[0487] ×: 2.30 or more

[0488] Evaluation Criteria in (Examples 18-27) and (Comparative Examples 8-18)

[0489] The difference between the dielectric loss tangent and dielectric constant of Comparative Example 8 (which does not contain block copolymers) and each of the Examples or Comparative Examples (Comparative Example 8 - Examples or Comparative Examples) was used for evaluation.

[0490] Dielectric loss tangent

[0491] ◎:0.0012 or more

[0492] ○: 0.0010 or higher and less than 0.0012

[0493] △: 0.0080 or higher and less than 0.0010

[0494] ×: Less than 0.0080 (including identical values ​​and positive differences)

[0495] Dielectric constant

[0496] ◎:0.12 or more

[0497] ○: 0.10 or higher and less than 0.12

[0498] △: 0.08 or higher and less than 0.10

[0499] ×: Less than 0.08 (including identical values ​​and positive differences)

[0500] Evaluation Criteria in (Examples 28-43) and (Comparative Examples 19-40)>

[0501] The difference between the dielectric loss tangent and dielectric constant of Comparative Example 19 (which does not contain block copolymers) and each of the Examples or Comparative Examples (Comparative Example 19 - Examples or Comparative Examples) was used for evaluation.

[0502] Dielectric loss tangent

[0503] ◎: 0.010 or more

[0504] ○: 0.008 or higher and less than 0.010

[0505] △: 0.005 or higher and less than 0.008

[0506] ×: Less than 0.005 (including identical values ​​and positive differences)

[0507] Dielectric constant

[0508] ◎:0.4 or more

[0509] ○: 0.3 or higher and less than 0.4

[0510] △: 0.2 or higher and less than 0.3

[0511] ×: Less than 0.2 (including identical values ​​and positive differences)

[0512] Evaluation Criteria in (Examples 44-55) and (Comparative Examples 41-55)>

[0513] The difference in dielectric loss tangent and dielectric constant between Comparative Example 41 (which does not contain block copolymers) and each of the Examples or Comparative Examples (Comparative Example 41 - Examples or Comparative Examples) was used for evaluation.

[0514] Dielectric loss tangent

[0515] ◎:0.0012 or more

[0516] ○: 0.0010 or higher and less than 0.0012

[0517] △: 0.0080 or higher and less than 0.0010

[0518] ×: Less than 0.0080 (including identical values ​​and positive differences)

[0519] Dielectric constant

[0520] ◎:0.15 or more

[0521] ○: 0.12 or higher and less than 0.15

[0522] △: 0.10 or higher and less than 0.12

[0523] ×: Less than 0.10 (including identical values ​​and positive differences)

[0524] ((2) Strength (glass transition temperature: Tg))

[0525] The dynamic viscoelasticity of the resin compositions of the examples and comparative examples described below was measured, and the temperature at which the tanδ was maximized was determined as the glass transition temperature (Tg).

[0526] A high Tg indicates high strength over a wide temperature range.

[0527] The measuring device used was ARES (trade name manufactured by TA Instruments), set to stretch mode. The test sample was a test piece cut from the cured film (described later) with a length of 35 mm, a width of approximately 12.5 mm, and a thickness of 0.3 mm, which was used as the test sample.

[0528] The measurements were performed at a frequency of 10 rad / s and a measurement temperature of -150 to 270 °C.

[0529] (3) Preservation stability)

[0530] The state of the varnishes of the examples and comparative examples described below after standing at 30°C / 50%RH was observed, and the number of days and presence or absence of layer separation and / or gel formation were evaluated according to the following criteria.

[0531] ◎: More than 120 days (including no precipitation)

[0532] ○: More than 90 days

[0533] △: More than 30 days

[0534] ×: Less than 30 days

[0535] [Preparation of the resin composition]

[0536] (Examples 1-27), (Comparative Examples 1-18)

[0537] Using the above-mentioned components, a resin composition was prepared by the following preparation method.

[0538] The component ratios and physical properties are shown in Tables 3 to 6 below.

[0539] First, add each component to toluene (using premium grade manufactured by Wako Pure Chemical Industries Co., Ltd.), stir to dissolve, and prepare a varnish with a concentration of 20% to 50% by mass.

[0540] The varnish was applied to the non-stick KAPTON film at a speed of 30 mm / s, and then dried at 100°C for 30 minutes under a nitrogen atmosphere using a blower dryer to obtain the film. The obtained film was then cured at 200°C for 90 minutes under a nitrogen atmosphere using a blower dryer to obtain the cured film.

[0541] The cured film was supplied to the evaluation samples.

[0542] As can be seen from Examples 1-27 and Comparative Examples 1-18, the cured resin compositions using the block copolymers of the present invention exhibit excellent balance in dielectric properties, strength, and heat resistance.

[0543] As can be seen from the above, the cured resin composition containing the block copolymer of the present invention is suitable for use as glass cloth and for use in printed circuit boards using metal laminates.

[0544]

[0545]

[0546]

[0547]

[0548]

[0549] (Examples 28-43), (Comparative Examples 19-40)

[0550] In addition to the above-mentioned components, the following components are also used, and a resin composition is prepared according to the following preparation method.

[0551] <Component (II): Free radical initiator>

[0552] Perbutyl P-90 (manufactured by NOF Corporation)

[0553] <Component (III): Polar Resin>

[0554] Bisphenol A type epoxy resin EXA-850CRP (manufactured by DIC Corporation)

[0555] Phenoxy resin YP-50S (manufactured by Nippon Steel Chemical Co., Ltd.)

[0556] <Component (IV): Curing Agent>

[0557] 1-Benzyl-2-phenylimidazolium (Tokyo Chemical Industry Co., Ltd.)

[0558] Phenolic curing agent KA-1163 (manufactured by DIC Corporation)

[0559] The component ratios and physical properties are shown in Tables 7 to 9 below.

[0560] First, except for the phenolic curing agent, add toluene and stir to dissolve it, thus preparing a varnish with a concentration of 20% to 50% by mass.

[0561] When using a phenolic curing agent, a 50% by mass phenolic curing agent solution is prepared by using methyl ethyl ketone (a premium grade manufactured by Wako Pure Chemical Industries, Ltd.) as a solvent. This solution is then added to a varnish containing ingredients other than the aforementioned phenolic curing agent, and the mixture is stirred to prepare the varnish.

[0562] The varnish was applied to the anti-sticking KAPTON film at a speed of 30 mm / s, and then dried at 100°C for 30 minutes under nitrogen flow using a blower dryer to obtain the film.

[0563] The obtained membrane was cured at 200°C for 90 minutes under nitrogen flow using a blower dryer to obtain a cured membrane.

[0564] The cured film was supplied to the evaluation samples.

[0565]

[0566]

[0567]

[0568] (Examples 44-55), (Comparative Examples 41-55)

[0569] In addition to the above-mentioned components, the following components are also used, and a resin composition is prepared according to the following preparation method.

[0570] <Component (III): Polar Resin>

[0571] [Polyimide resin]

[0572] Bis(3-ethyl-5-methyl-4-maleimidephenyl)methane (BMI-70) (manufactured by KI Chemicals Co., Ltd.)

[0573] 4,4'-Bismaleimide diphenylmethane (BMI-H) (manufactured by KI Chemical Co., Ltd.)

[0574] <Component (IV): Curing Agent>

[0575] 2,2-bis(4-cyanoester phenyl)propane, a cyanate-based curing agent (manufactured by Tokyo Chemical Co., Ltd.)

[0576] Diamine-based curing agent 4,4'-diaminodiphenylmethane (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0577] The component ratios and physical properties are shown in Tables 10 and 11 below.

[0578] First, the polyimide resin as a polar resin and the cyanate ester curing agent and / or diamine curing agent as curing agents are dissolved at 160°C according to the mixing ratios in Tables 10-11 below, and reacted for 6 hours under stirring to obtain bismaleimide triazine resin oligomers.

[0579] The obtained bismaleimide triazine resin oligomer was dissolved in toluene, the remaining components were added, and the mixture was stirred to dissolve, thus preparing a varnish with a concentration of 20% to 50% by mass.

[0580] The varnish was applied to the non-stick KAPTON film at a speed of 30 mm / s. Then, it was dried at 100°C for 30 minutes under a nitrogen atmosphere using a blower dryer to obtain the film.

[0581] For the membrane, a curing reaction was carried out at 200°C for a maximum of 90 minutes under nitrogen flow using a blower dryer to obtain a cured membrane.

[0582] The cured film was supplied to the evaluation samples.

[0583] As can be seen from Examples 28-55 and Comparative Examples 19-55, the cured resin compositions using the block copolymers of the present invention exhibit excellent balance in dielectric properties, strength, and heat resistance.

[0584] As can be seen from the above, the cured resin composition containing the block copolymer of the present invention is suitable for glass cloth applications and printed circuit board applications using metal laminates.

[0585]

[0586]

[0587] Industrial applicability

[0588] The block copolymers of the present invention, the resin compositions comprising the above-mentioned block copolymers, and the cured products are industrially applicable as materials for films, prepregs, electronic circuit boards, and next-generation communication boards.

Claims

1. A block copolymer having: Polymer blocks (A) primarily composed of vinyl aromatic monomer units; and Polymer blocks (B) mainly composed of conjugated diene monomer units and / or polymer blocks (C) composed of vinyl aromatic monomer units and conjugated diene monomer units, The block copolymer satisfies the following conditions (i) to (iii), <Condition(i)> The block copolymer has a weight-average molecular weight of less than 35,000; <Condition(ii)> The content of vinyl aromatic monomer units in the block copolymer is more than 55% by mass and less than 95% by mass; <Condition (iii)> The polymer block (B) and / or the polymer block (C) comprises units (a) derived from 1,2-bonding and / or 3,4-bonding and units (b) derived from 1,4-bonding, wherein, when the total content of the polymer block (B) and / or the polymer block (C) is set to 100%, the content of the units (a) derived from 1,2-bonding and / or 3,4-bonding is more than 20% and less than 80%.

2. The block copolymer of claim 1, wherein, In condition (i), the weight-average molecular weight of the block copolymer is 500 or more and 30,000 or less.

3. The block copolymer of claim 2, wherein, In condition (i), the weight-average molecular weight of the block copolymer is 500 or more and 25,000 or less.

4. The block copolymer according to any one of claims 1 to 3, wherein, In condition (ii), the content of vinyl aromatic monomer units in the block copolymer is more than 55% by mass and less than 90% by mass.

5. The block copolymer according to any one of claims 1 to 3, wherein, The hydrogenation rate of the block copolymer is 0-51%.

6. A resin composition comprising: Component (I): The block copolymer according to any one of claims 1 to 5; and Select at least one component from the group consisting of components (II) to (IV) below. Component (II): Free radical initiator; Component (III): Polar resin, excluding component (I); Component (IV): Curing agent, excluding component (II).

7. The resin composition of claim 6, wherein, The component (III) is at least one selected from the group consisting of epoxy resin, polyimide resin, polyphenylene ether resin, liquid crystal polyester resin and fluorine resin.

8. The resin composition according to claim 6 or 7, wherein, The component (II) is at least one selected from the group consisting of organic peroxides and azo compounds.

9. A cured product comprising any one of claims 1 to 5.

10. A cured product, which is a cured product of the resin composition according to any one of claims 6 to 8.

11. A resin film comprising the resin composition according to any one of claims 6 to 8.

12. A prepreg, which is a composite of a substrate and the resin composition according to any one of claims 6 to 8.

13. The prepreg as claimed in claim 12, wherein, The substrate is glass cloth.

14. A laminate having the resin film and metal foil as described in claim 11.

15. A laminate comprising a cured prepreg of claim 12 or 13 and a metal foil.

16. A material for an electronic circuit board comprising the cured material of claim 10.

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