Hydrogenated conjugated diene copolymer, resin composition, cured product, resin film, prepreg, laminate, and printed wiring board

Abstract

This hydrogenated conjugated diene copolymer is a random copolymer having a vinyl aromatic monomer unit and a conjugated diene monomer unit, wherein the random copolymer is hydrogenated and has a weight average molecular weight of at most 35,000.

Description

[Technical Field]

[0001] The present invention relates to a hydrogenated conjugated diene copolymer, a resin composition, a cured product, a resin film, a prepreg, a laminate, and a printed wiring board. [Background technology]

[0002] 2. Description of the Related Art In recent years, with the remarkable progress in information network technology and the expansion of services utilizing information networks, electronic devices are required to handle larger amounts of information and to process faster. To meet these demands, materials with low dielectric loss are required for various substrates such as printed circuit boards and flexible substrates.

[0003] BACKGROUND ART In order to obtain materials with small dielectric loss, cured resins containing, as their main component, a thermosetting resin such as an epoxy resin, which has a low dielectric constant and a low dielectric dissipation factor and excellent mechanical properties such as strength, or a thermoplastic resin such as a polyphenylene ether resin, have been studied and disclosed. However, the materials disclosed so far still have room for improvement in terms of low dielectric constant and low dielectric loss tangent, and when these materials are used in printed circuit boards, there is a problem that the amount of information and processing speed are limited.

[0004] To overcome these problems, various rubber components have been proposed as modifiers for the above-mentioned thermosetting resins and thermoplastic resins. For example, Patent Document 1 discloses at least one elastomer selected from the group consisting of copolymers of vinyl aromatic compounds and olefinic alkene compounds, hydrogenated products thereof, and homopolymers of vinyl aromatic compounds, as a modifier for lowering the dielectric loss tangent and dielectric constant of polyphenylene ether resins. Furthermore, Patent Document 2 discloses a styrene-based elastomer as a modifier for lowering the dielectric loss tangent and dielectric constant of an epoxy resin. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-147486 [Patent Document 2] Japanese Patent Publication No. 2020-15861 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the cured products of the resin compositions using the modifiers disclosed in Patent Documents 1 and 2 still have insufficient low dielectric constants and low dielectric loss tangents, and the addition of the modifiers reduces the tensile strength, making it impossible to obtain sufficient strength.

[0007] Therefore, an object of the present invention is to provide a hydrogenated conjugated diene copolymer, which gives a cured product having a low dielectric constant, a low dielectric dissipation factor, and excellent tensile strength, and a resin composition containing the hydrogenated conjugated diene copolymer. [Means for solving the problem]

[0008] As a result of intensive research conducted by the present inventors to solve the above-mentioned problems of the conventional art, they found that a cured product of a resin composition containing a hydrogenated conjugated diene-based copolymer having a predetermined structure has a low dielectric constant and a low dielectric dissipation factor, and also has excellent strength properties, and thus completed the present invention. That is, the present invention is as follows.

[0009] [1] Component (I): A hydrogenated conjugated diene copolymer, which is a random copolymer having vinyl aromatic monomer units and conjugated diene monomer units, and which is hydrogenated and has a weight average molecular weight of 35,000 or less. and, A resin composition containing the following component (III) and at least one component selected from the group consisting of the following components (II) and (IV): Component (II): Radical initiator Component (III): Polar resin (excluding component (I)) Component (IV): Hardener (excluding component (II)) The resin composition, wherein the component (III) is at least one selected from the group consisting of epoxy resins, polyimide resins, polyphenylene ether resins, liquid crystal polyester resins, and fluorine-containing resins. [2] The hydrogenation rate of the hydrogenated conjugated diene copolymer is 5 to 95%. The above-mentioned [1] resin composition . [3] the conjugated diene copolymer before hydrogenation contains units (a) derived from 1,2-bonds and / or 3,4-bonds and units (b) derived from 1,4-bonds, When the total content of the conjugated diene monomer units is taken as 100%, the content of the units (a) derived from the 1,2-bond and / or the 3,4-bond is 80% or less. The above-mentioned [1] resin composition . [4] the conjugated diene copolymer before hydrogenation contains units (a) derived from 1,2-bonds and / or 3,4-bonds and units (b) derived from 1,4-bonds, When the total content of the conjugated diene monomer units is taken as 100%, the content of the units (a) derived from the 1,2-bond and / or the 3,4-bond is 80% or less. The above-mentioned [2] resin composition . [5] The hydrogenation rate of the hydrogenated conjugated diene copolymer is 15 to 85%. [1] to [4] resin composition . [6] [5] The hydrogenated conjugated diene copolymer according to any one of [1] to [5], wherein the content of vinyl aromatic monomer units in the hydrogenated conjugated diene copolymer is 35 to 75 mass %. resin composition . 〔7〕 the component (III) is at least one polar resin selected from the group consisting of epoxy resins, polyimide resins, and polyphenylene ether resins; The component (I) The hydrogenated conjugated diene copolymer has a vinyl aromatic monomer unit content of 35 to 75 mass%. The aforementioned Any one of [1] to [6] The resin composition according to claim 1. 〔8〕 The component (III) is an epoxy resin. [1] to [7] The resin composition according to any one of the above. 〔9〕 The aforementioned [1] to [8] A cured product of the resin composition according to any one of the preceding items. 〔10〕 The aforementioned [1] to [8] A resin film comprising the resin composition according to any one of the above items. 〔11〕 A substrate; The aforementioned [1] to [8] a resin composition according to any one of the above items; Prepreg is a composite material. 〔12〕 The substrate is a glass cloth. 〔11〕 The prepreg according to claim 1. 〔13〕 The aforementioned 〔10〕 A laminate comprising the resin film according to claim 1 and a metal foil. 〔14〕 The aforementioned

[11] or

[12] a cured product of the prepreg according to claim 1, and a metal foil; A laminate having: 〔15〕 The aforementioned 〔9〕 A printed wiring board comprising the cured product according to claim 1. [Effects of the Invention]

[0010] According to the present invention, there are provided a hydrogenated conjugated diene copolymer, which gives a cured product having a low dielectric constant, a low dielectric dissipation factor, and excellent tensile strength, and a resin composition containing the hydrogenated conjugated diene copolymer. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, an embodiment of the present invention (hereinafter referred to as "the present embodiment") will be described in detail. It should be noted that the following embodiments are merely examples for explaining the present invention, and are not intended to limit the present invention to the following content, and the present invention can be implemented in various modified forms within the scope of its gist.

[0012] [Hydrogenated conjugated diene copolymer] The hydrogenated conjugated diene copolymer of this embodiment is a random polymer having vinyl aromatic monomer units and conjugated diene monomer units, and the random copolymer is hydrogenated and has a weight average molecular weight of 35,000 or less. The hydrogenated conjugated diene copolymer of this embodiment gives a cured product that has a low dielectric constant and a low dielectric loss tangent and is also excellent in strength properties.

[0013] The conjugated diene monomer unit refers to a structural unit derived from a conjugated diene compound in a polymer formed by polymerization of a conjugated diene compound. Conjugated diene compounds are diolefins having a pair of conjugated double bonds. 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. 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 easily available, are advantageous from the viewpoint of cost, and can easily be copolymerized with styrene, which is widely used as a vinyl aromatic compound, as described below. These may be used alone or in combination of two or more. The conjugated diene compound may be a biotechnological compound.

[0014] The vinyl aromatic monomer unit refers to a structural unit derived from a vinyl aromatic compound in a polymer formed by polymerization of a vinyl aromatic compound. 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, and N,N-diethyl-p-aminoethylstyrene. These may be used alone or in combination of two or more.

[0015] (random copolymer) The hydrogenated conjugated diene copolymer of the present embodiment is a random copolymer having vinyl aromatic monomer units and conjugated diene monomer units. The hydrogenated conjugated diene copolymer of the present embodiment preferably does not contain any intentionally added monomers other than the vinyl aromatic compound and the conjugated diene compound. Regarding the distribution state of the vinyl aromatic monomer units in the hydrogenated conjugated diene copolymer, the vinyl aromatic monomer units may be distributed uniformly or in a tapered manner in the hydrogenated conjugated diene copolymer. Further, there may be a plurality of parts where the vinyl aromatic monomer units are distributed uniformly and / or a plurality of parts where the vinyl aromatic monomer units are distributed in a tapered manner, but it is preferable that no block consisting of only vinyl aromatic monomer units exists.

[0016] Since there is a difference in the polymerization rate between the vinyl aromatic compound and the conjugated diene compound, even when polymerization is carried out in a state in which both compounds are contained in the system, depending on the polymerization conditions, the conjugated diene compound may be consumed first, and the proportion of the vinyl aromatic compound may increase in the latter half, and even blocks of vinyl aromatic monomer units may be formed. In the production process of the hydrogenated conjugated diene polymer of this embodiment, it is preferable to set conditions such as adding a randomizer or adjusting the polymerization temperature so that blocks of vinyl aromatic monomer units are not formed. However, as long as the hydrogenated conjugated diene copolymer as a whole can be regarded as a random copolymer, a state in which blocks of vinyl aromatic monomer units and / or conjugated diene monomer units are partially formed is not excluded.

[0017] Specifically, the embodiment that can be considered a random copolymer means an embodiment in which the polymer portion consisting only of vinyl aromatic monomer units is less than 15% by mass of the total amount of vinyl aromatic monomer units constituting the hydrogenated conjugated diene-based copolymer of this embodiment, and is preferably less than 13% by mass, more preferably less than 10% by mass, even more preferably less than 7% by mass, even more preferably less than 5% by mass, still more preferably less than 4% by mass, and particularly preferably less than 3% by mass. Since the amount of the polymer portion consisting only of the above-mentioned vinyl aromatic monomer units is less than 15 mass % of the total amount of vinyl aromatic monomer units, the hydrogenated conjugated diene-based copolymer of this embodiment can be distinguished from block copolymers having a polymer block structure intentionally containing vinyl aromatic monomer units and conjugated diene monomer units as constituent units, and has good compatibility with components (II), (III), and (IV) described below, resulting in excellent strength and dielectric performance.

[0018] The content of each monomer unit constituting the hydrogenated conjugated diene copolymer of this embodiment can be measured by a method using a nuclear magnetic resonance (NMR) spectrometer (the method described in Y. Tanaka, et al., RUBBER CHEMISTRY and TECHNOLOGY 54, 685 (1981), hereinafter referred to as the "NMR method") using the hydrogenated conjugated diene copolymer of this embodiment as a sample.

[0019] As described below, the resin composition of this embodiment contains the hydrogenated conjugated diene-based copolymer of this embodiment (component (I)), component (II): a radical initiator, component (III): a polar resin, and component (IV): a curing agent. Components (II), (III), and (IV) described below have a polar group. From the viewpoint of solubility parameter, vinyl aromatic compounds tend to have higher compatibility with components (II), (III), and (IV) than conjugated diene compounds, but the hydrogenated conjugated diene copolymer of this embodiment has a high polarity in the entire polymer chain due to the copolymerization of a vinyl aromatic compound. As a result, the hydrogenated conjugated diene copolymer is a random copolymer of vinyl aromatic monomer units and conjugated diene monomer units, which further improves compatibility with components (III) and (IV), thereby improving the strength of the resin composition of this embodiment and the cured product described below.

[0020] Conjugated diene compounds have radical reactivity, and as described above, the random copolymer has excellent compatibility with components (II), (III), and (IV). Therefore, the conjugated diene monomer units in the random copolymer are located in the vicinity of components (II), (III), and (IV), creating a state in which the conjugated diene monomer units are more likely to react with these components.

[0021] Furthermore, by improving the compatibility of the random copolymer described above with components (II), (III), and (IV), the resin composition and cured product of this embodiment described below tend to suppress a decrease in polymer mobility and polarization due to an external electric field, thereby improving the dielectric loss tangent and dielectric constant of the resin composition and cured product. The loss (dielectric constant) caused by polarization of the polymer due to an external electric field and the energy loss (dielectric loss tangent) caused by heat generation due to movement can both be suppressed by ensuring sufficient compatibility and reactivity with components (III) and (IV) described below. Therefore, the hydrogenated conjugated diene-based copolymer of this embodiment, which is a copolymer composed of the vinyl aromatic monomer units and conjugated diene monomer units, leads to increased strength and a low dielectric loss tangent and dielectric constant of the resin composition and cured product of this embodiment.

[0022] From the viewpoints of improving the strength of the cured product and reducing the dielectric loss tangent and dielectric constant, the content of monomer units other than vinyl aromatic monomers and conjugated diene monomer units in the hydrogenated conjugated diene polymer of this embodiment is preferably 30% by mass or less, more preferably 20% by mass or less, even more preferably 10% by mass or less, and even more preferably 0% by mass (no other monomers are intentionally added).

[0023] (Hydrogenation) The hydrogenated conjugated diene copolymer of this embodiment is a copolymer in which hydrogen has reacted with conjugated diene monomer units, that is, a hydrogenated copolymer. Hydrogenation reduces the polarity of the conjugated diene copolymer, which can reduce both the loss (dielectric constant) caused by polarization of the polymer in an external electric field and the energy loss (dielectric dissipation factor) caused by heat generated by movement, and therefore the resin composition and cured product containing the hydrogenated conjugated diene copolymer of this embodiment tend to have a low dielectric dissipation factor and a low dielectric constant. In other words, the structure having a random structure of conjugated diene monomer units and vinyl aromatic monomer units and containing hydrogenated conjugated diene monomer units ensures compatibility with other components (the random structure is dominant over the hydrogenation rate) by having a random structure, and also reduces polarity from the perspective of dielectric performance by having a hydrogenated structure, resulting in a design with an excellent balance of properties.

[0024] In the hydrogenated conjugated diene copolymer of this embodiment, the unsaturated bonds derived from the conjugated diene compound are hydrogenated from the viewpoints of the reactivity with the other components and the dielectric performance. The hydrogenation rate is preferably 5% or more, more preferably 10% or more, even more preferably 15% or more, still more preferably 20% or more, even more preferably 30% or more, and particularly preferably 35% or more. From the viewpoint of ensuring sufficient reactivity with the other components, the upper limit of the hydrogenation rate is preferably 95% or less, more preferably 94% or less, even more preferably 93% or less, still more preferably 92% or less, even more preferably 91% or less, particularly preferably 90% or less, and most preferably 85% or less. The resin composition of this embodiment, which will be described later, may contain a non-hydrogenated conjugated diene copolymer insofar as the dielectric performance and strength described above are not impaired, but from the viewpoint of the dielectric performance and strength described above, the content of the non-hydrogenated conjugated diene copolymer in the resin composition of this embodiment is preferably 20% by mass or less, more preferably 15% by mass or less, even more preferably 10% by mass or less, even more preferably 5% by mass or less, and still more preferably 0% by mass. When it is 0% by mass, the resin composition does not contain a conjugated diene copolymer having a weight-average molecular weight exceeding 35,000.

[0025] As described above, the hydrogenation rate of the hydrogenated conjugated diene polymer of this embodiment is preferably 15% or more, more preferably 20% or more, and even more preferably 25% or more. From the viewpoint of the reactivity and dielectric performance described above, the upper limit is preferably 85% or less, more preferably 80% or less, and even more preferably 75% or less. When the hydrogenation rate of the hydrogenated conjugated diene polymer is 15% or more, the dielectric performance of the hydrogenated conjugated diene copolymer is good, and the resin composition and cured product of this embodiment tend to have excellent dielectric performance. When the hydrogenation rate of the hydrogenated conjugated diene polymer is 85% or less, the reactivity with component (III): polar resin and the reactivity between the hydrogenated conjugated diene copolymers themselves can be sufficiently ensured, and the resin composition and cured product of this embodiment tend to have excellent toughness.

[0026] The method for hydrogenating the conjugated diene copolymer is not particularly limited, and known methods can be applied. In the hydrogenation reaction, known hydrogenation catalysts can be used, such as (1) supported heterogeneous hydrogenation catalysts in which metals such as Ni, Pt, Pd, and Ru are supported on carbon, silica, alumina, diatomaceous earth, and the like, (2) so-called Ziegler-type hydrogenation catalysts in which transition metal salts such as organic acid salts or acetylacetonates of Ni, Co, Fe, and Cr, and reducing agents such as organoaluminum, and (3) homogeneous hydrogenation catalysts such as so-called organometallic complexes of organometallic compounds such as Ti, Ru, Rh, and Zr. Specific examples of the hydrogenation catalyst that can be used include the hydrogenation catalysts described in Japanese Patent Publication Nos. 42-8704, 43-6636, 63-4841, 1988-37970, 1989-53851, and 2-9041.

[0027] Preferred hydrogenation catalysts include titanocene compounds and reducing organometallic compounds. The titanocene compound may be one described in JP-A-8-109219. Examples of the titanocene compound include, but are not limited to, compounds having at least one ligand with a substituted or unsubstituted cyclopentadienyl skeleton, indenyl skeleton, or fluorenyl skeleton, such as biscyclopentadienyltitanium dichloride and monopentamethylcyclopentadienyltitanium trichloride. The titanocene compound may contain one of the above skeletons alone or a combination of two of them. Examples of reducing organometallic compounds include, but are not limited to, organic alkali metal compounds such as organolithium compounds, organomagnesium compounds, organoaluminum compounds, organoboron compounds, and organozinc compounds. These may be used alone or in combination of two or more.

[0028] The hydrogenation rate of the hydrogenated conjugated diene copolymer of this embodiment can be controlled within the above-mentioned numerical range by adjusting the reaction temperature, reaction time, hydrogen supply amount, catalyst amount, etc. in the hydrogenation method. The reaction temperature during hydrogenation is preferably 55 to 200°C, more preferably 60 to 170°C, and even more preferably 65 to 160°C. The hydrogen pressure used in the hydrogenation reaction is preferably 0.1 to 15 MPa, more preferably 0.2 to 10 MPa, and even more preferably 0.3 to 5 MPa. The reaction time is usually 3 minutes to 10 hours, and preferably 10 minutes to 5 hours. The hydrogenation reaction can be carried out using either a batch process, a continuous process, or a combination thereof.

[0029] (Weight average molecular weight (Mw)) The hydrogenated conjugated diene copolymer of this embodiment has a weight average molecular weight (Mw) of 35,000 or less. The weight-average molecular weight can be measured by the method described in the Examples below, and is obtained by determining the peak molecular weight of a chromatogram obtained by measurement using gel permeation chromatography (hereinafter, sometimes abbreviated as GPC) based on a calibration curve (prepared using the peak molecular weight of the standard polystyrene) obtained from measurement of commercially available standard polystyrene.

[0030] The molecular weight distribution is the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn). The single-peak molecular weight distribution of the conjugated diene copolymer of the present embodiment measured by GPC is preferably 5.0 or less, more preferably 4.0 or less, even more preferably 3.0 or less, and still more preferably 2.5 or less, from the viewpoint of preventing deterioration of handleability due to contamination with low-molecular-weight polymers described later.

[0031] The weight-average molecular weight of the hydrogenated conjugated diene copolymer of this embodiment is 35,000 or less, which improves crosslinkability, forms a uniform mesh structure, and provides a high-strength cured product. Furthermore, compatibility with components (III) and (IV), which will be described later, improves, and the resin composition and cured product of this embodiment tend to have a low dielectric constant and a low dielectric loss tangent. Furthermore, when a prepreg is formed using the resin composition of this embodiment, when a substrate such as a glass cloth described later is immersed in a varnish described later, since the weight-average molecular weight of the hydrogenated conjugated diene copolymer of this embodiment is 35,000 or less, the hydrogenated conjugated diene copolymers are uniformly crosslinked with each other and are uniformly compatible with component (III): a polar resin described later, and this tends to improve the strength of the cured product containing the hydrogenated conjugated diene copolymer and to reduce the dielectric tangent and dielectric constant. Furthermore, in the case of prepregs, the permeability into the substrate improves, making it possible to produce uniform prepregs, which tend to have improved strength, lower dielectric loss tangents, and lower dielectric constants. The weight-average molecular weight of the hydrogenated conjugated diene copolymer of this embodiment is 35,000 or less, preferably 30,000 or less, more preferably 25,000 or less, even more preferably 20,000 or less, and still more preferably 15,000 or less. There is no particular lower limit for the weight-average molecular weight of the hydrogenated conjugated diene copolymer, but from the viewpoint of suppressing stickiness of the hydrogenated conjugated diene copolymer and providing good handleability, a weight-average molecular weight of 500 or more is preferred. As described above, the resin composition of this embodiment may contain a conjugated diene copolymer having a weight-average molecular weight of more than 35,000, provided that the dielectric properties and strength are not impaired. However, if the weight-average molecular weight exceeds 35,000, the storage stability in the varnish form described below tends to deteriorate. This is thought to be because a high weight-average molecular weight of the conjugated diene copolymer increases the cohesive force between the conjugated diene copolymers, making them more likely to leach out in the varnish. In particular, when a highly polar resin such as an epoxy resin or a polyimide resin is used as component (III) described below, the conjugated diene copolymer has a lower polarity than the resins of component (III), which promotes cohesion between the conjugated diene copolymers, resulting in a significant deterioration in the storage stability of the resin composition. From the above-mentioned viewpoint, in the resin composition of this embodiment, the content of the conjugated diene copolymer having a weight-average molecular weight of more than 35,000 in the resin composition components is preferably 20% by mass or less, more preferably 15% by mass or less, even more preferably 10% by mass or less, even more preferably 5% by mass or less, and still more preferably 0% by mass or less.

[0032] Furthermore, if the reaction between hydrogenated conjugated diene copolymers proceeds excessively, the polymer tends to be over-crosslinked, resulting in a decrease in toughness. If the weight-average molecular weight of the hydrogenated conjugated diene polymer is large, the polymer is more likely to be over-crosslinked, resulting in a decrease in toughness. From this perspective, the weight-average molecular weight of the hydrogenated conjugated diene copolymer of this embodiment is 35,000 or less, preferably 30,000 or less, more preferably 25,000 or less, even more preferably 20,000 or less, and even more preferably 15,000 or less.

[0033] The weight average molecular weight and molecular weight distribution of the hydrogenated conjugated diene copolymer of this embodiment can be controlled within the above-mentioned numerical ranges by adjusting the polymerization conditions such as the amount of monomer added in the polymerization step, the timing of addition, the polymerization temperature, and the polymerization time.

[0034] (Vinyl aromatic monomer unit content) As mentioned above, in recent years, there has been a demand for miniaturization of printed circuit boards in line with the demand for miniaturization of various electronic devices. To miniaturize printed circuit boards, precise wiring is necessary, and in this case, materials for printed wiring boards tend to be required to have better toughness. The more flexible conjugated diene copolymer disperses and reacts with the radical initiator of component (II) and the rigid polar resin of component (III), which will be described later, to form a crosslinked structure, which tends to improve the toughness of the cured product of the resin composition of this embodiment, which will be described later. Generally, polyimide resins, epoxy resins, polyphenylene ether resins, etc. can be used as component (III): polar resin. However, when such resins are used, these resins have higher polarity than component (I): hydrogenated conjugated diene copolymer. Therefore, in order to improve dispersibility and reactivity and to obtain superior toughness from the above-mentioned viewpoint, it is preferable that component (I): hydrogenated conjugated diene copolymer also has high polarity. In other words, it is preferable that component (I): hydrogenated conjugated diene copolymer has a high content of vinyl aromatic monomer units and a low hydrogenation rate. On the other hand, hydrogenated conjugated diene copolymers with a high content of vinyl aromatic monomer units and a low hydrogenation rate tend to have poor dielectric properties, and the dielectric properties of the cured product of the resin composition of this embodiment, described below, also tend to be reduced. Therefore, by designing the content of vinyl aromatic monomer units and the hydrogenation rate in component (I): hydrogenated conjugated diene copolymer within appropriate ranges, it is possible to control the balance between dispersibility, reactivity, and the dielectric properties of the hydrogenated conjugated diene copolymer, and it tends to be possible to obtain a resin composition and a cured product that are excellent in toughness and dielectric properties.

[0035] From the above viewpoints, the content of vinyl aromatic monomer units in the hydrogenated conjugated diene copolymer of this embodiment is preferably 35% by mass or more, more preferably 40% by mass or more, and even more preferably 45% by mass or more. From the viewpoints of the reactivity and dielectric performance described above, the upper limit is preferably 75% by mass or less, more preferably 70% by mass or less, and even more preferably 65% ​​by mass or less. When the content of vinyl aromatic monomer units in the hydrogenated conjugated diene copolymer of this embodiment is 35% by mass or more, dispersibility with component (III): polar resin is good, and excellent toughness tends to be obtained. When the content of vinyl aromatic monomer units in the hydrogenated conjugated diene copolymer is 75% by mass or less, reactivity with component (III): polar resin and reactivity between hydrogenated conjugated diene copolymers are sufficiently ensured, the hydrogenated conjugated diene copolymer has excellent dielectric performance, and the resin composition and cured product of this embodiment described below tend to have excellent toughness and dielectric performance.

[0036] The content of the vinyl aromatic monomer unit in the hydrogenated conjugated diene copolymer of this embodiment can be measured by NMR, specifically, by the method described in the examples below. The content of the vinyl aromatic monomer unit in the hydrogenated conjugated diene copolymer of this embodiment can be controlled within the above-mentioned numerical range by adjusting the amount of the monomer added in the polymerization step.

[0037] (vinyl bond content) The hydrogenated conjugated diene copolymer of this embodiment contains conjugated diene monomer units derived from 1,2-bonds and / or 3,4-bonds (hereinafter sometimes referred to as unit (a)) and units derived from 1,4-bonds (hereinafter sometimes referred to as unit (b)). When the total content of conjugated diene monomer units in the conjugated diene copolymer before hydrogenation is taken as 100%, the content of units derived from 1,2-bonds and / or 3,4-bonds (vinyl bond content) is preferably 80% or less, more preferably 75% or less, and even more preferably 70% or less, from the viewpoint of the storage stability of a varnish using the resin composition of this embodiment. While the lower limit is not particularly limited, it is preferably 5% or more, more preferably 10% or more, even more preferably 15% or more, even more preferably 20% or more, still more preferably 25% or more, and particularly preferably 30% or more, from the viewpoint of the reactivity of the conjugated diene monomer units.

[0038] The content of the unit (a) can be controlled within the above-mentioned range by using a regulator such as a polar compound in the polymerization process of the conjugated diene copolymer, and can be measured by the method described in the examples below. Examples of the regulator include tertiary amine compounds and ether compounds, with tertiary amine compounds being preferred. The tertiary amine compound is a compound of the general formula: R1R2R3N (wherein R1, R2, and R3 are a hydrocarbon group having 1 to 20 carbon atoms or a hydrocarbon group having a tertiary amino group). 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-dipiperidinoethane, trimethylaminoethylpiperazine, N,N,N',N",N"-pentamethylethylenetriamine, and N,N'-dioctyl-p-phenylenediamine. The amount of the regulator added is preferably 0.1 mol or more, more preferably 0.5 mol or more, and even more preferably 1.0 mol or more, per mol of the polymerization initiator described below.

[0039] [Method for producing hydrogenated conjugated diene copolymer] The hydrogenated conjugated diene copolymer of the present embodiment can be produced, for example, by carrying out living anionic polymerization in a hydrocarbon solvent using a polymerization initiator such as an organic alkali metal compound, followed by a hydrogenation reaction.

[0040] Examples of hydrocarbon solvents include, but are not limited to, aliphatic hydrocarbons such as n-butane, isobutane, n-pentane, n-hexane, n-heptane, and n-octane; alicyclic hydrocarbons such as cyclohexane, cycloheptane, and methylcycloheptane; and aromatic hydrocarbons such as benzene, toluene, xylene, and ethylbenzene.

[0041] Examples of the polymerization initiator include organic alkali metal compounds such as 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. Examples of alkali metals include lithium, sodium, and potassium. Examples of organic alkali metal compounds include aliphatic and aromatic hydrocarbon lithium compounds having 1 to 20 carbon atoms, including compounds containing one lithium atom per molecule, dilithium compounds containing multiple lithium atoms per molecule, trilithium compounds, and tetralithium compounds. Specific examples of organic alkali metal compounds include n-propyllithium, n-butyllithium, sec-butyllithium, tert-butyllithium, n-pentyllithium, n-hexyllithium, benzyllithium, phenyllithium, tolyllithium, a reaction product of diisopropenylbenzene and sec-butyllithium, and a reaction product of divinylbenzene, sec-butyllithium, and a small amount of 1,3-butadiene. Furthermore, 1-(t-butoxy)propyllithium, as disclosed in U.S. Patent No. 5,708,092, and lithium compounds into which one to several isoprene monomer molecules have been inserted to improve solubility, siloxy-containing alkyllithiums such as 1-(t-butyldimethylsiloxy)hexyllithium, as disclosed in British Patent No. 2,241,239, amino-containing alkyllithiums such as diisopropylamidelithium and hexamethyldisilazidelithium, as disclosed in U.S. Patent No. 5,527,753, can also be used.

[0042] As a method for polymerizing a vinyl aromatic compound and a conjugated diene compound using an organic alkali metal compound as a polymerization initiator, a conventionally known method can be applied. The polymerization method may be, for example, batch polymerization, continuous polymerization, or a combination of these. In particular, batch polymerization is preferred for obtaining a uniform polymer. The polymerization temperature is preferably from 0°C to 180°C, more preferably from 30°C to 150°C. The polymerization time varies depending on the conditions, but is usually within 48 hours, preferably 0.1 to 10 hours. The polymerization atmosphere is preferably an inert gas atmosphere such as nitrogen gas. The polymerization pressure is not particularly limited, as long as it is set within a pressure range that allows the monomer and solvent to be maintained in a liquid phase within the above-mentioned temperature range. Furthermore, care must be taken to prevent the introduction of impurities that may inactivate the catalyst and living polymer, such as water, oxygen, carbon dioxide, etc., into the polymerization system.

[0043] Furthermore, at the end of the polymerization step, a required amount of a bifunctional or higher functional coupling agent may be added to carry out a coupling reaction, but the coupling rate is preferably 40% or less, more preferably 30% or less, even more preferably 20% or less, and it is even more preferable that no coupling agent is included.

[0044] The bifunctional coupling agent is not particularly limited and any known bifunctional coupling agent can be used. Examples of bifunctional coupling agents include alkoxysilane compounds such as trimethoxysilane, triethoxysilane, tetramethoxysilane, tetraethoxysilane, dimethyldimethoxysilane, diethyldimethoxysilane, dichlorodimethoxysilane, dichlorodiethoxysilane, trichloromethoxysilane, and trichloroethoxysilane; dihalogen compounds such as dichloroethane, dibromoethane, dimethyldichlorosilane, and dimethyldibromosilane; and acid esters such as methyl benzoate, ethyl benzoate, phenyl benzoate, and phthalates.

[0045] Furthermore, as the trifunctional or higher polyfunctional coupling agent, any known agent can be used, and there is no particular limitation. Examples of polyfunctional coupling agents with three or more functional groups include polyalcohols with three or more functional groups, polyhydric epoxy compounds such as epoxidized soybean oil, diglycidyl bisphenol A, and 1,3-bis(N-N'-diglycidylaminomethyl)cyclohexane; n (wherein R is a hydrocarbon group having 1 to 20 carbon atoms, X is a halogen, and n is an integer of 3 to 4), such as methylsilyl trichloride, t-butylsilyl trichloride, silicon tetrachloride, and bromides thereof; n (wherein R is a hydrocarbon group having 1 to 20 carbon atoms, X is a halogen, and n is an integer of 3 to 4), for example, polyvalent halogen compounds such as methyltin trichloride, t-butyltin trichloride, and tin tetrachloride. Dimethyl carbonate, diethyl carbonate, etc. may also be used.

[0046] The hydrogenation reaction of the conjugated diene copolymer can be carried out by a known method using a known hydrogenation catalyst, as described above.

[0047] If necessary, catalyst residues can be removed from the solution of the hydrogenated conjugated diene copolymer of the present embodiment obtained as described above, and the hydrogenated conjugated diene copolymer can be separated from the solution. Compounds containing metal atoms in the polymerization initiator used in producing a hydrogenated conjugated diene copolymer by anionic living polymerization and in the hydrogenation catalyst used in the hydrogenation reaction tend to react with moisture in the air during a desolvation step, etc., to generate specific metal compounds that remain in the hydrogenated conjugated diene copolymer. When these compounds are contained in a cured product, the dielectric constant and dielectric loss tangent tend to increase, and further, ion migration tends to occur easily in electronic material applications.

[0048] Examples of residual metal compounds include compounds of metals contained in polymerization initiators and hydrogenation catalysts, such as oxides of various atoms such as titanium oxide, amorphous titanium oxide, orthotitanic acid, metatitanic acid, titanium hydroxide, nickel hydroxide, nickel monoxide, lithium oxide, lithium hydroxide, cobalt oxide, and cobalt hydroxide, as well as composite oxides of various atoms and different metals such as lithium titanate, barium titanate, strontium titanate, nickel titanate, and nickel-iron oxide. To achieve a low dielectric constant and low dielectric loss tangent in the cured product of this embodiment and to reduce the likelihood of ion migration, the amount of residual metal compounds in the conjugated diene copolymer of this embodiment is preferably 150 ppm or less, more preferably 130 ppm or less, even more preferably 100 ppm or less, and even more preferably 90 ppm or less. Specific examples of residual metals typically include Ti, Ni, Li, and Co.

[0049] The method for reducing the amount of residual metal in the hydrogenated conjugated diene copolymer of this embodiment can be any known method, and is not particularly limited. For example, a method of adding water and carbon dioxide gas after the hydrogenation reaction of the conjugated diene copolymer to neutralize the hydrogenation catalyst residue, or a method of adding an acid in addition to water and carbon dioxide gas to neutralize the hydrogenation catalyst residue can be used. Specifically, the method described in Japanese Patent Application No. 2014-557427 can be used. Even when these metal removal methods are used, water containing hydroxides of metal compounds is mixed in during the desolvation process of the hydrogenated conjugated diene copolymer, and the resulting metals are generally present in amounts of about 1 to 15 ppm. Therefore, it is preferable to remove 20% or more of the amount of metal added to the hydrogenated conjugated diene copolymer, more preferably 30% or more, even more preferably 40% or more, even more preferably 50% or more, and still more preferably 60% or more.

[0050] Furthermore, the amount of residual metal in the hydrogenated conjugated diene copolymer of the present embodiment can also be reduced by reducing the amounts of the polymerization initiator and hydrogenation catalyst added, but reducing the amount of polymerization initiator increases the molecular weight of the hydrogenated conjugated diene copolymer, and if the molecular weight falls outside the preferred molecular weight range described above, the strength of the cured product tends to decrease. Furthermore, when performing a hydrogenation reaction, reducing the amount of hydrogenation catalyst increases the hydrogenation reaction time and the hydrogenation reaction temperature, which tends to significantly reduce productivity.

[0051] Examples of methods for separating the solvent when recovering the hydrogenated conjugated diene copolymer include a method in which a polar solvent that is a poor solvent for the hydrogenated conjugated diene copolymer, such as acetone or alcohol, is added to the reaction solution after hydrogenation to precipitate and recover the hydrogenated conjugated diene copolymer; a method in which the reaction solution is poured into hot water with stirring and the solvent is removed by steam stripping to recover the copolymer; and a method in which the copolymer solution is directly heated to distill off the solvent.

[0052] The hydrogenated conjugated diene copolymer may contain various stabilizers such as phenol-based stabilizers, phosphorus-based stabilizers, sulfur-based stabilizers, and amine-based stabilizers.

[0053] In the process for producing the hydrogenated conjugated diene copolymer of this embodiment, a step of forming a "polar group" may be carried out to the extent that the dielectric performance is not impaired. Examples of polar groups include, but are not limited to, atomic groups containing at least one functional group selected from the group consisting of a hydroxyl group, a carboxyl group, a carbonyl group, a thiocarbonyl group, an acid halide group, an acid anhydride group, a carboxylic acid group, a thiocarboxylic acid group, an aldehyde group, a thioaldehyde group, a carboxylic acid ester group, an amide group, a sulfonic acid group, a sulfonate ester group, a phosphoric acid group, a phosphoric acid ester group, an amino group, an imino group, a nitrile group, a pyridyl group, a quinoline group, an epoxy group, a thioepoxy group, a sulfide group, an isocyanate group, an isothiocyanate group, a silicon halide group, a silanol group, an alkoxy silicon group, a tin halide group, a boronic acid group, a boron-containing group, a boronate salt group, an alkoxytin group, and a phenyltin group.

[0054] The polar group can be formed by reacting a modifier with the conjugated diene copolymer. Examples of the modifying agent include, but are not limited to, tetraglycidyl meta-xylenediamine, tetraglycidyl-1,3-bisaminomethylcyclohexane, ε-caprolactone, δ-valerolactone, 4-methoxybenzophenone, γ-glycidoxyethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyldimethylphenoxysilane, bis(γ-glycidoxypropyl)methylpropoxysilane, 1,3-dimethyl-2-imidazolidinone, 1,3-diethyl-2-imidazolidinone, N,N′-dimethylpropyleneurea, N-methylpyrrolidone, maleic acid, maleic anhydride, maleic anhydride imide, fumaric acid, itaconic acid, acrylic acid, methacrylic acid, glycidyl methacrylate, and crotonic acid.

[0055] The method for forming the polar group is not particularly limited and any known method can be applied. For example, there may be mentioned a melt-kneading method, or a method in which the components are dissolved or dispersed in a solvent or the like and mixed to react with each other. In addition to the method using the above-mentioned modifying agent, a method of polymerization using a polymerization initiator having a functional group or an unsaturated monomer having a functional group by anionic living polymerization can also be applied. Further examples include a method of modifying a conjugated diene copolymer by forming a functional group at the living end of the copolymer or by subjecting a modifying agent containing a functional group to an addition reaction, and a method of reacting a copolymer with an organic alkali metal compound such as an organic lithium compound (metallation reaction) and then subjecting the polymer to which the organic alkali metal compound has been added to a modifying agent having a functional group.

[0056] [Resin composition] The resin composition of this embodiment contains the hydrogenated conjugated diene copolymer of this embodiment (component (I)) and at least one component selected from the group consisting of the following components (II) to (IV): Component (II): Radical initiator Component (III): Polar resin (excluding component (I)) Component (IV): Hardener (excluding component (II)) From the viewpoint of reducing the dielectric constant, the dielectric loss tangent, and the flexibility of the resin composition of the present embodiment and the cured product thereof, the resin composition of the present embodiment preferably contains component (I): a hydrogenated conjugated diene copolymer and component (II): a radical initiator.

[0057] (Component (II): Radical initiator) As the radical initiator, a conventionally known one can be used, for example, a thermal radical initiator. Examples of thermal radical initiators include, but are not limited to, hydroperoxides such as diisopropylbenzene hydroperoxide (Percumyl P), cumene hydroperoxide (Percumyl H), and t-butyl hydroperoxide (Perbutyl H); α,α-bis(t-butylperoxy-m-isopropyl)benzene (Perbutyl P), dicumyl peroxide (Percumyl D), 2,5-dimethyl-2,5-bis(t-butylperoxy)hexane (Perhexa 25B), t-butylcumyl peroxide (Perbutyl C), di-t-butyl peroxide (Perbutyl D), 2,5-dimethyl-2,5-bis(t-butylperoxy)hexane (Perhexa 25B), t-butylcumyl peroxide (Perbutyl C), di-t-butyl peroxide (Perbutyl D), and 2,5-dimethyl-2,5-bis(t-butylperoxy)hexane (Perhexa 25B). Examples of the peroxide include dialkyl peroxides such as hexyne-3 (Perhexyne 25B) and t-butylperoxy-2-ethylhexanoate (Perbutyl O), ketone peroxides, peroxyketals such as n-butyl-4,4-di-(t-butylperoxy)valerate (Perhexa V), organic peroxides such as diacyl peroxides, peroxydicarbonates, and peroxyesters, and azo compounds such as 2,2-azobisisobutylnitrile, 1,1'-(cyclohexane-1-1-carbonitrile), 2,2'-azobis(2-cyclopropylpropionitrile), and 2,2'-azobis(2,4-dimethylvaleronitrile). These may be used alone or in combination of two or more.

[0058] (Component (III): Polar resin) The resin composition of this embodiment preferably contains a polar resin (excluding component (I)) as component (III) from the viewpoint of imparting properties such as adhesion to a predetermined substrate, within a range that does not impair the dielectric properties of the cured product. By containing a polar resin, the resin composition of this embodiment tends to have excellent adhesion to a predetermined substrate. When component (III) is a polar resin having radical reactivity, the amount of the radical initiator (component (II)) described above can be adjusted appropriately depending on the reactivity, or component (II) can be omitted.

[0059] Examples of the radically reactive polar resin as component (III) include a homopolymer of a compound having at least one vinyl group and / or a halogen atom in the polymer, and a copolymer of the compound having a vinyl group and / or a halogen atom with any other compound. From the viewpoint of the dielectric properties of the resin composition and the cured product of this embodiment, a polymer having a vinyl group is preferred.

[0060] The polymer having a vinyl group may be a polymer consisting of a repeating unit having a vinyl group, a polymer of a compound having a vinyl group and a polar group, or a polymer having a vinyl group obtained by reacting the polar groups of a compound having a polar group. Examples of compounds having a vinyl group and a polar group include, but are not limited to, (meth)acrylic acid (in the present invention, "(meth)acrylic" means methacrylic or acrylic), maleic acid, maleic acid monoalkyl ester, carboxyl group-containing vinyl monomers such as fumaric acid, vinyl sulfonic acid, (meth)allyl sulfonic acid, methyl vinyl sulfonic acid, styrene sulfonic acid, sulfone group-containing vinyl monomers such as vinyl sulfonic acid, (meth)allyl sulfonic acid, methyl vinyl sulfonic acid, styrene sulfonic acid, hydroxyl group-containing vinyl monomers such as hydroxystyrene, N-methylol (meth)acrylamide, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, phosphate group-containing vinyl monomers such as 2-hydroxyethyl (meth)acryloyl phosphate, phenyl-2-acryloyloxyethyl phosphate, 2-acryloyloxyethyl phosphonic acid, hydroxy Examples of the vinyl monomer include hydroxy group-containing vinyl monomers such as styrene, N-methylol (meth)acrylamide, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, polyethylene glycol (meth)acrylate, and 1-butene-3-ol; amino group-containing vinyl monomers such as aminoethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, and diethylaminoethyl (meth)acrylate; amide group-containing vinyl monomers such as (meth)acrylamide, N-methyl (meth)acrylamide, and N-butylacrylamide; nitrile group-containing vinyl monomers such as (meth)acrylonitrile, cyanostyrene, and cyanoacrylate; and epoxy group-containing vinyl monomers such as glycidyl methacrylate, tetrahydrofurfuryl (meth)acrylate, and p-vinylphenyl phenyloxide. Examples of compounds containing a halogen element include, but are not limited to, vinyl chloride, vinyl bromide, vinylidene chloride, allyl chloride, chlorostyrene, bromostyrene, dichlorostyrene, chloromethylstyrene, tetrafluorostyrene, and chloroprene.

[0061] (Component (IV): Curing agent) When the radical reactivity of the above-mentioned component (III) is low, from the viewpoint of reactivity, the resin composition of the present embodiment preferably contains component (IV): a curing agent (excluding component (II)). Component (IV): a curing agent generally has the function of reacting with component (III): a polar resin to cure the resin composition. The "reaction" of component (III) and component (IV) means that the polar groups of each component have covalent bonding properties. When polar groups react with each other, for example, when the OH of a carboxyl group is eliminated, the original polar group changes or disappears. If this results in the formation of a covalent bond, this is included in the definition of the polar groups being "reactive."

[0062] From the viewpoint of curing function, it is preferable that component (IV): curing agent has at least two polar groups in one molecular chain that can react with the functional groups of component (III): polar resin. The component (IV) may be used alone or in combination of two or more. The type of polar group contained in component (III) and component (IV) is not particularly limited, but examples thereof include: Epoxy and carboxyl groups, carbonyl groups, ester groups, imidazole groups, hydroxyl groups, amino groups, mercaptan groups, benzoxazine groups, carbodiimide groups, phenolic hydroxyl groups; Amino and carboxyl groups, carbonyl groups, hydroxyl groups, acid anhydride groups, sulfonic acid, and aldehyde groups; Isocyanate and hydroxyl groups, carboxylic acids, phenolic hydroxyl groups; anhydride groups and hydroxy groups; silanol groups, hydroxyl groups, and carboxylic acid groups; Halogens and carboxylic acid groups, carboxylic acid ester groups, amino groups, phenol groups, thiol groups; Alkoxy and hydroxy groups, alkoxide groups, amino groups; Maleimide and cyanate groups etc. Whether the bond of these polar groups is component (III) or component (IV) can be selected arbitrarily.

[0063] In addition, cases where the polar group of component (III) and the polar group of component (IV) do not react directly but can react by adding a curing accelerator such as a catalyst are also included in the definition of "reactive." For example, when component (III) is a polar resin having epoxy groups and component (IV) is a curing agent having acid anhydride groups, the reactivity between epoxy groups and acid anhydride groups is usually very low, but by adding a compound having amino groups as a curing accelerator, the epoxy groups and amino groups in component (III) react, and some or all of the epoxy groups in component (III) become hydroxyl groups. The hydroxyl groups react with the acid anhydride groups of component (IV) the curing agent, thereby curing the resin composition.

[0064] From the viewpoint of reactivity, the ratio of the polar resin (III) to the curing agent (IV) is preferably a molar ratio of polar groups (polar groups of component (III):polar groups of component (IV)) of 1:0.01 to 1:20, more preferably 1:0.05 to 1:15, and even more preferably 1:0.1 to 1:10.

[0065] Component (IV): Curing agent. Examples of curing agents having an ester group include EXB9451, EXB9460, EXB, 9460S, HPC8000-65T, HPC8000H-65TM, EXB8000L-65TM, EXB8150-65T, and EXB9416-70BK manufactured by DIC Corporation, and YLH1026, DC808, YLH1026, YLH1030, and YLH1048 manufactured by Mitsubishi Chemical Corporation.

[0066] Examples of curing agents having a hydroxyl group include MEH-7700, MEH-7810, MEH-7851, NHN, CBN, and GPH manufactured by Nippon Kayaku Co., Ltd., SN170, SN180, SN190, SN475, SN485, SN495, SN-495V, and SN375 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., and TD-2090, LA-7052, LA-7054, LA-1356, LA-3018-50P, and EXB-9500 manufactured by DIC Corporation.

[0067] Examples of curing agents having a benzoxazine group include ODA-BOZ manufactured by JFE Chemical Corporation, HFB2006M manufactured by Showa Polymer Co., Ltd., and Pd and Fa manufactured by Shikoku Chemicals Corporation.

[0068] Examples of curing agents having an isocyanate group include bifunctional cyanate resins such as bisphenol A dicyanate, polyphenol cyanate, oligo(3-methylene-1,5-phenylene cyanate), 4,4'-methylenebis(2,6-dimethylphenyl cyanate), 4,4'-ethylidene diphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis(4-cyanate)phenylpropane, 1,1-bis(4-cyanatephenylmethane), bis(4-cyanate-3,5-dimethylphenyl)methane, 1,3-bis(4-cyanatephenyl-1-(methylethylidene))benzene, bis(4-cyanatephenyl)thioether, and bis(4-cyanatephenyl)ether; polyfunctional cyanate resins derived from phenol novolac and cresol novolac; and prepolymers in which these cyanate resins are partially converted to triazine. Commercially available products include PT30, PT60, ULL-950S, BA230, and BA230S75 manufactured by Lonza Japan.

[0069] Examples of curing agents having a carbodiimide group include V-03 and V-07 manufactured by Nisshinbo Chemical Inc.

[0070] Examples of the curing agent having an amino group include 4,4'-methylenebis(2,6-dimethylaniline), diphenyldiaminosulfone, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, m-phenylenediamine, m-xylylenediamine, diethyltoluenediamine, 4,4'-diaminodiphenyl ether, 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dihydroxybenzidine, 2,2-bis(3-amino-4-hydroxybenzoyl) Examples of commercially available bis(4-aminophenoxy)phenyl propane include 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, and bis(4-(3-aminophenoxy)phenyl)sulfone. Examples of commercially available bis(4-aminophenoxy)phenyl propane include KAYABOND C-200S, KAYABOND C-100, KAYAHARD AA, KAYAHARD AB, and KAYAHARD AS manufactured by Nippon Kayaku Co., Ltd., and Epicure W manufactured by Mitsubishi Chemical Corporation. From the viewpoint of reactivity, the amino group is preferably a primary amine and / or a secondary amine, more preferably a primary amine.

[0071] Examples of curing agents having an acid anhydride group include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic anhydride, hydrogenated methylnadic anhydride, trialkyltetrahydrophthalic anhydride, dodecenyl succinic anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, trimellitic anhydride, pyromellitic anhydride, and benzophenone tetracarbohydrate. Examples of suitable anhydrides include carboxylic acid dianhydride, biphenyltetracarboxylic acid dianhydride, naphthalenetetracarboxylic acid dianhydride, oxydiphthalic dianhydride, 3,3'-4,4'-diphenylsulfonetetracarboxylic acid dianhydride, 1,3,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-C]furan-1,3-dione, ethylene glycol bis(anhydrotrimellitate), and polymeric acid anhydrides such as styrene-maleic acid resin, which is a copolymer of styrene and maleic acid.

[0072] Furthermore, compounds having at least two of the aforementioned radically reactive structures also have the function of reacting with component (III) to cure the resin composition, and such compounds can also be used as curing agents for component (IV). Examples of compounds having at least two radically reactive structures include allyl monomers such as triallyl isocyanurate (Taikyu, manufactured by Mitsubishi Chemical Corporation), tris(2-hydroxyethyl) isocyanurate, diallyl fumarate, diallyl adipate, triallyl citrate, and diallyl hexahydrophthalate.

[0073] When the resin composition of the present embodiment contains component (III), component (III): polar resin is preferably at least one selected from the group consisting of epoxy resins, polyimide resins, polyphenylene ether resins, liquid crystal polyester resins, and fluorine-containing resins from the viewpoint of heat resistance, and more preferably at least one selected from the group consisting of epoxy resins, polyimide resins, and polyphenylene ether resins. Furthermore, from the viewpoint of adhesion to metal foil such as copper foil, it is particularly preferred to use at least one selected from the group consisting of epoxy resins, polyimide resins, and polyphenylene ether resins as component (III): polar resin, and to use a hydrogenated conjugated diene copolymer having a vinyl aromatic monomer unit content of 35 to 75 mass% as component (I).

[0074] The polyimide resin may be any resin that has an imide bond in the repeating unit and falls into the category of polyimide resins. For example, a typical polyimide structure obtained by polycondensation (imide bond) of a tetracarboxylic acid or its dianhydride with a diamine can be used. From the viewpoint of curability, it is preferable that the polyimide structure has an unsaturated group at the end. Examples of polyimide resins having an unsaturated group at the end include maleimide polyimide resins, nadimide polyimide resins, and allylnadimide polyimide resins. The tetracarboxylic acid or its dianhydride is not limited to the following, but examples thereof include aromatic tetracarboxylic acid dianhydrides, alicyclic tetracarboxylic acid dianhydrides, aliphatic tetracarboxylic acid dianhydrides, etc. These may be used alone or in combination of two or more. The diamine is not particularly limited, but examples thereof include aromatic diamines, alicyclic diamines, aliphatic diamines, etc., which are commonly used in the synthesis of polyimides. These may be used alone or in combination of two or more. Furthermore, from the viewpoint of reducing the dielectric constant and the dielectric loss tangent of the resin composition and the cured product of the present embodiment, at least one of the tetracarboxylic acid, the dianhydride thereof, and the diamine may have one or more functional groups selected from the group consisting of a fluorine group, a trifluoromethyl group, a hydroxyl group, a sulfone group, a carbonyl group, a heterocycle, a long-chain alkyl group, and an allyl group.

[0075] The polyimide resin may be a commercially available polyimide resin, but is not limited thereto. Examples include Neoprim (registered trademark) C-3650 (manufactured by Mitsubishi Gas Chemical Company, Inc., trade name), Neoprim C-3G30 (manufactured by Mitsubishi Gas Chemical Company, Inc., trade name), Neoprim C-3450 (manufactured by Mitsubishi Gas Chemical Company, Inc., trade name), Neoprim P500 (manufactured by Mitsubishi Gas Chemical Company, Inc., trade name), BT (bismaleimide-triazine) resin (manufactured by Mitsubishi Gas Chemical Company, Inc.), JL-20 (manufactured by New Japan Chemical Company, Inc., trade name) (the varnish of these polyimide resins may contain silica), Rikacoat SN20 and Rikacoat PN20 manufactured by New Japan Chemical Company, Pyre-ML manufactured by IST, and U-type polyimide resin. Examples of such products include Upia-AT, Upia-ST, Upia-NF, and Upia-LB manufactured by Nippon Kayaku Co., Ltd.; PIX-1400, PIX-3400, PI2525, PI2610, HD-3000, and AS-2600 manufactured by Hitachi Chemical Co., Ltd.; HPC-5000, HPC-5012, HPC-1000, HPC-5020, HPC-3010, HPC-6000, HPC-9000, HCI-7000, HCI-1000S, HCI-1200E, and HCI-1300 manufactured by Showa Denko K.K.; BMI-2300 manufactured by Daiwa Kasei Kogyo Co., Ltd.; and MIR-3000 manufactured by Shin-Nippon Kayaku Co., Ltd.

[0076] The polyphenylene ether resin, component (III), may be any resin that belongs to the category known as polyphenylene ether resin and contains phenylene ether units as repeating structural units, and may also contain structural units other than phenylene ether units. In the homopolymer having a phenylene ether unit, the phenylene group in the phenylene unit may or may not have a substituent. Examples of the substituent include acrylic groups such as an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, and a tert-butyl group; cyclic alkyl groups such as a cyclohexyl group; vinyl groups, allyl groups, isopropenyl groups, 1-butenyl groups, 1-pentenyl groups, p-vinylphenyl groups, p-isopropenylphenyl groups, m-vinylphenyl groups, m-isopropenylphenyl groups, o-vinylphenyl groups, o-isopropenylphenyl groups, p-vinylbenzyl groups, p-isopropenylbenzyl groups, m-vinylbenzyl groups, m-isopropenylbenzyl groups, o-vinylbenzyl groups, o-isopropenylbenzyl groups, p-vinylphenylethenyl groups, p-vinylphenylpropenyl groups, p-vinylphenylbutenyl groups, m-vinylphenylethenyl groups, m-vinylphenylpropenyl groups, m-vinylphenylbutenyl groups, and o-vinylphenylethenyl groups. Examples of functional group-containing substituents include unsaturated bond-containing substituents such as thenyl group, o-vinylphenylpropenyl group, o-vinylphenylbutenyl group, methacryl group, acrylic group, 2-ethylacrylic group, and 2-hydroxymethylacrylic group; and functional group-containing substituents such as hydroxyl group, carboxyl group, carbonyl group, thiocarbonyl group, acid halide group, acid anhydride group, carboxylic acid group, thiocarboxylic acid group, aldehyde group, thioaldehyde group, carboxylic acid ester group, amide group, sulfonic acid group, sulfonic acid ester group, phosphoric acid group, phosphate ester group, amino group, imino group, nitrile group, pyridyl group, quinoline group, epoxy group, thioepoxy group, sulfide group, isocyanate group, isothiocyanate group, silicon halide group, silanol group, alkoxy silicon group, tin halide group, boronic acid group, boron-containing group, boronate salt group, alkoxytin group, and phenyltin group. From the viewpoint of the curability of the resin composition of this embodiment, the polyphenylene ether resin preferably has a polar group that is radical-reactive and / or reactive with the curing agent (IV).

[0077] From the viewpoint of the curability of the resin composition of the present embodiment, the polyphenylene ether resin as component (III) preferably has a molecular weight of 100,000 or less, more preferably 50,000 or less, and even more preferably 10,000 or less. The polyphenylene ether resin may be linear, crosslinked, or branched.

[0078] The liquid crystal polyester resin, which is the component (III), is a polyester that forms an anisotropic molten phase and may be any resin that falls into the category of liquid crystal polyester resins. Examples include "X7G" manufactured by Eastman Kodak Company, Xyday manufactured by Dartco, Econol manufactured by Sumitomo Chemical Co., Ltd., and Vectra manufactured by Celanese.

[0079] The fluorine-based resin as component (III) may be any resin that falls into the category of fluorine-based resins, and is an olefin polymer containing a fluorine group. Examples of the fluorine-based resin include polytetrafluoroethylene, perfluoroalkoxyalkane, ethylene-tetrafluoroethylene copolymer, perfluoroethylene-propene copolymer, polyvinylidene fluoride, polychlorotrifluoroethylene, and ethylene-chlorotrifluoroethylene copolymer.

[0080] The epoxy resin as component (III) may be any resin that falls into the category of epoxy resins, and from the viewpoint of strength, it preferably has two or more epoxy groups in one molecule. The epoxy resins may be used alone or in combination of two or more. Examples of epoxy resins include bixylenol-type epoxy resins, bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, bisphenol S-type epoxy resins, bisphenol AF-type epoxy resins, dicyclopentadiene-type epoxy resins, trisphenol-type epoxy resins, naphthol novolac-type epoxy resins, phenol novolac-type epoxy resins, tert-butyl-catechol-type epoxy resins, naphthalene-type epoxy resins, naphthol-type epoxy resins, anthracene-type epoxy resins, glycidylamine-type epoxy resins, glycidyl ester-type epoxy resins, cresol novolac-type epoxy resins, biphenyl-type epoxy resins, alicyclic epoxy resins, heterocyclic epoxy resins, spiro ring-containing epoxy resins, cyclohexane-type epoxy resins, cyclohexane dimethanol-type epoxy resins, naphthylene ether-type epoxy resins, trimethylol-type epoxy resins, and tetraphenylethane-type epoxy resins.

[0081] Furthermore, when an epoxy resin is used as component (III) from the viewpoint of reactivity with component (I): hydrogenated conjugated diene copolymer, it is preferable to also contain component (IV) curing agent. In this case, examples of the polar group possessed by component (IV) curing agent include a carboxy group, an imidazole group, a hydroxyl group, an amino group, a mercaptan group, a benzoxazine group, and a carbodiimide group. From the viewpoint of reactivity, a carboxy group, an imidazole group, a hydroxyl group, a benzoxazine group, and a carbodiimide group are preferred. From the viewpoint of dielectric performance, a hydroxyl group, a carboxy group, an imidazole group, a benzoxazine group, and a carbodiimide group are more preferred, and a hydroxyl group, a carboxy group, and a carbodiimide group are even more preferred.

[0082] Furthermore, when two or more polar resins having different radical reactivities are used as component (III), it is preferable to use a combination of component (II): a radical initiator and component (IV): a curing agent from the viewpoint of curability of the resin composition of this embodiment. For example, when a maleimide-type polyimide resin having excellent radical reactivity and a bisphenol A epoxy resin having no radical reactivity are used as component (III), it is preferable to add the above-mentioned component (II): a radical initiator and the above-mentioned component (IV): a curing agent from the viewpoint of curability.

[0083] Furthermore, when a polar resin having a high melting point and high rigidity is used as the polar resin (component (III)), the resin composition of this embodiment does not need to contain component (IV). Examples of the polar resin having a high melting point and high rigidity as component (III) include liquid crystal polyester resins and fluorine-based resins such as polytetrafluoroethylene. Since component (III) has a high melting point and high rigidity, the composition tends to have a strength required for practical use even when component (IV) is not contained.

[0084] (Component (V): Additive) The resin composition of the present embodiment may further contain various additives such as a curing accelerator, a filler, and a flame retardant as component (V). In addition, the additives contained in the component (I) hydrogenated conjugated diene copolymer are also synonymous with the component (V) of the resin composition.

[0085] The curing accelerator is added to promote the reactivity between the above-mentioned components, and any conventionally known accelerator can be used, such as a phosphorus-based curing accelerator, an amine-based curing accelerator, an imidazole-based curing accelerator, a guanidine-based curing accelerator, or a metal-based curing accelerator. The curing accelerator may be used alone or in combination of two or more.

[0086] Examples of phosphorus-based curing accelerators include triphenylphosphine, phosphonium borate compounds, tetraphenylphosphonium tetraphenylborate, n-butylphosphonium tetraphenylborate, tetrabutylphosphonium decanoate, (4-methylphenyl)triphenylphosphonium thiocyanate, tetraphenylphosphonium thiocyanate, and butyltriphenylphosphonium thiocyanate, with triphenylphosphine and tetrabutylphosphonium decanoate being preferred.

[0087] Examples of the amine curing accelerator include trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine, benzyldimethylamine, 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.

[0088] Examples of the imidazole curing accelerator include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, 2, 4-Diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, Examples of the imidazole compound include imidazole compounds such as 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazoline, and 2-phenylimidazoline, as well as adducts of imidazole compounds with epoxy resins, and 2-ethyl-4-methylimidazole and 1-benzyl-2-phenylimidazole are preferred. As the imidazole-based curing accelerator, a commercially available product may be used, for example, P200-H50 manufactured by Mitsubishi Chemical Corporation.

[0089] Examples of the guanidine curing accelerator include dicyandiamide, 1-methylguanidine, 1-ethylguanidine, 1-cyclohexylguanidine, 1-phenylguanidine, 1-(o-tolyl)guanidine, dimethylguanidine, diphenylguanidine, trimethylguanidine, tetramethylguanidine, pentamethylguanidine, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, and 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene. Examples include chloro[4.4.0]dec-5-ene, 1-methylbiguanide, 1-ethylbiguanide, 1-n-butylbiguanide, 1-n-octadecylbiguanide, 1,1-dimethylbiguanide, 1,1-diethylbiguanide, 1-cyclohexylbiguanide, 1-allylbiguanide, 1-phenylbiguanide, and 1-(o-tolyl)biguanide, and dicyandiamide and 1,5,7-triazabicyclo[4.4.0]dec-5-ene are preferred.

[0090] Examples of metal-based curing accelerators include organometallic complexes or organometallic salts of metals such as cobalt, copper, zinc, iron, nickel, manganese, and tin. Examples of organometallic complexes include, but are not limited to, organic cobalt complexes such as cobalt(II) acetylacetonate and cobalt(III) acetylacetonate, organic copper complexes such as copper(II) acetylacetonate, organic zinc complexes such as zinc(II) acetylacetonate, organic iron complexes such as iron(III) acetylacetonate, organic nickel complexes such as nickel(II) acetylacetonate, and organic manganese complexes such as manganese(II) acetylacetonate. Examples of organic metal salts include, but are not limited to, zinc octoate, tin octoate, zinc naphthenate, cobalt naphthenate, tin stearate, and zinc stearate.

[0091] Examples of fillers include, but are not limited to, inorganic fillers such as silica, calcium carbonate, magnesium carbonate, magnesium hydroxide, aluminum hydroxide, calcium sulfate, barium sulfate, carbon black, glass fiber, glass beads, glass balloons, glass flakes, graphite, titanium oxide, potassium titanate whiskers, carbon fiber, alumina, kaolin clay, silicic acid, calcium silicate, quartz, mica, talc, clay, zirconia, potassium titanate, alumina, and metal particles; and organic fillers such as wood chips, wood powder, pulp, and cellulose nanofibers. These may be used alone or in combination of two or more. The shape of these fillers is not particularly limited and may be any of scaly, spherical, granular, powdery, irregular, etc.

[0092] The resin composition or cured product of this embodiment is often exposed to high temperatures during molding, etc., and to prevent shrinkage due to the temperature change and deformation of the molded product, the filler preferably has a small linear expansion coefficient. From the viewpoint of reducing the linear expansion coefficient, silica is preferred as the filler, and examples of silica include amorphous silica, fused silica, crystalline silica, synthetic silica, and hollow silica.

[0093] Examples of the flame retardant include halogen-based flame retardants such as bromine compounds, phosphorus-based flame retardants such as aromatic compounds, and flame retardants containing aromatic bromine compounds such as metal hydroxides, alkyl sulfonates, antimony trioxide, aluminum hydroxide, magnesium hydroxide, zinc borate, hexabromobenzene, decabromodiphenylethane, 4,4-dibromobiphenyl, and ethylenebistetrabromophthalimide. These flame retardants may be used singly or in combination of two or more. The above flame retardants also include so-called flame retardant assistants, which by themselves have a low flame retardancy effect but when used in combination with other flame retardants, exhibit a synergistically superior effect.

[0094] Fillers and flame retardants that have been previously surface-treated with a surface treatment agent such as a silane coupling agent can also be used. Examples of surface treatment agents include fluorine-containing silane coupling agents, aminosilane coupling agents, epoxysilane coupling agents, mercaptosilane coupling agents, silane coupling agents, alkoxysilanes, organosilazane compounds, titanate coupling agents, etc. These may be used alone or in combination.

[0095] There are no particular restrictions on the other additives, so long as they are generally used in compounding resin compositions and cured products. Examples of other additives include, but are not limited to, pigments and / or colorants such as carbon black and titanium oxide; lubricants such as stearic acid, behenic acid, zinc stearate, calcium stearate, magnesium stearate, and ethylene bisstearamide; mold release agents; plasticizers such as organic polysiloxanes, fatty acid esters such as phthalate esters, adipate compounds, and azelaate compounds, and mineral oil; antioxidants such as hindered phenols and phosphorus-based heat stabilizers; hindered amine light stabilizers; benzotriazole-based ultraviolet absorbers; antistatic agents; organic fillers; thickeners; antifoaming agents; leveling agents; resin additives such as adhesion promoters; other additives, or mixtures thereof.

[0096] From the viewpoint of achieving the aforementioned low dielectric constant and low dielectric loss tangent, it tends to be preferable that the resin composition of the present embodiment does not contain a pigment, a colorant, a lubricant, a release agent, or an antistatic agent.

[0097] The resin composition in this embodiment may be a mixture of the components melted and kneaded together, or may be a mixture of the components dissolved in a solvent in which they can be dissolved and stirred (hereinafter referred to as "varnish"), but varnish is preferred from the viewpoint of ease of handling. Examples of solvents that make up the varnish include ketones such as acetone, methyl ethyl ketone (MEK), cyclohexanone, and γ-butyrolactone; acetate esters such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, carbitol acetate, and diethyl glycol monoacerate; 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. The organic solvents may be used alone or in combination of two or more.

[0098] [Cured product] The cured product of the present embodiment contains the hydrogenated conjugated diene copolymer of the present embodiment described above. The cured product of the present embodiment is a cured product of the resin composition of the present embodiment, and is obtained by subjecting the resin composition to a curing reaction at a given temperature for a given time. The concept encompasses not only a completely cured product, but also a form in which only a portion of the resin composition is cured and contains uncured components (semi-cured product). In the process for producing the laminate described below, a step of further curing the cured product may be carried out. The reaction temperature in the curing step of the cured product of 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 of this embodiment is a varnish, it is preferable to carry out the curing reaction after drying and removing the solvent. Drying may be carried out by a conventionally known method such as heating or hot air blowing, and is preferably carried out at a temperature lower than the curing reaction temperature. The amount of solvent in the resin composition after drying is preferably 10% by mass or less, more preferably 5% by mass or less.

[0099] [Resin film] The resin film of the present embodiment contains the resin composition of the present embodiment. The resin film of this embodiment can be obtained, for example, by spreading a varnish made of the resin composition of this embodiment onto a predetermined support to form a uniform thin film, followed by drying to remove the solvent. Such a resin film can be wound into a roll and stored.

[0100] [Prepreg] The prepreg of the present embodiment includes a substrate and the resin composition of the present embodiment impregnated into, coated on, or laminated onto the substrate. That is, the prepreg of the present embodiment is a composite of the resin composition of the present embodiment and the substrate. The prepreg can be obtained, for example, by impregnating a substrate such as glass cloth with the varnish that is the resin composition of the present embodiment, and then removing the solvent by the drying method described above. Examples of substrates include various glass cloths such as roving cloth, cloth, chopped mat, and surfacing mat; asbestos cloth, metal fiber cloth, and other synthetic or natural inorganic fiber cloths; woven or nonwoven fabrics obtained from liquid crystal fibers such as wholly aromatic polyamide fiber, wholly aromatic polyester fiber, and polybenzoxazole fiber; 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 cloth obtained from paper-glass blended fiber yarn; and polytetrafluoroethylene porous film. From the viewpoint of dielectric performance, glass cloth is preferred. These substrates may be used singly or in combination of two or more. The proportion of solids in the prepreg made of the resin composition of this embodiment is preferably 30 to 80% by mass, more preferably 40 to 70% by mass. Having this proportion of 30% by mass or more tends to provide better insulation reliability when the prepreg is used for electronic substrates, etc. Having this proportion of 80% by mass or less tends to provide better mechanical properties, such as rigidity, when used for electronic substrates, etc.

[0101] [Laminate] The laminate of this embodiment includes the resin film and metal foil described above. Alternatively, the laminate of this embodiment may include a cured product of the prepreg described above and metal foil. The laminate of this embodiment can be produced, for example, by a step (a) of laminating a resin film made of the resin composition of this embodiment onto a substrate to form a resin layer, a step (b) of heating and pressurizing the resin layer to flatten it and harden it, and a step (c) of further forming a predetermined wiring layer made of a metal foil on the resin layer. In step (a), the method for laminating the resin film on the substrate is not particularly limited, but examples thereof include lamination methods using a multi-stage press, a vacuum press, an atmospheric pressure laminator, or a laminator that heats and presses under vacuum, and a method using a laminator that heats and presses under vacuum is preferred. In the method using this laminator, even if the target electronic circuit board has a fine wiring circuit on the surface, the spaces between the circuits can be filled with resin without leaving voids. Furthermore, lamination may be performed by a batch method or a continuous method using a roll or the like.

[0102] Examples of the substrate include the substrates constituting the prepreg described above, as well as glass epoxy substrates, metal substrates, polyester substrates, polyimide substrates, polyphenylene ether substrates, fluororesin substrates, etc. The surface of the substrate on which the resin layer is to be laminated may be roughened in advance, and the number of substrate layers is not limited.

[0103] In the step (b), the resin film and the substrate laminated in the step (a) are heated and pressurized to be flattened. The conditions can be adjusted as desired depending on the type of substrate and the composition of the resin film, but preferred ranges are, for example, a temperature of 100 to 300°C, a pressure of 0.2 to 20 MPa, and a time of 30 to 180 minutes. In the step (c), a predetermined wiring layer made of a metal foil is further formed on the resin layer produced by heating and pressing the resin film and the substrate. The formation method is not particularly limited, and includes conventionally known methods, such as subtractive etching methods and semi-additive methods. The subtractive method is a method of forming the desired wiring by forming an etching resist layer on a metal layer in a shape corresponding to the desired pattern shape, and then performing a development process to dissolve and remove the metal layer in the areas where the resist has been removed with a chemical solution. The semi-additive method is a method in which a metal coating is formed on the surface of a resin layer by electroless plating, a plating resist layer of a shape corresponding to the desired pattern is formed on the metal coating, a metal layer is then formed by electrolytic plating, and the unnecessary electroless plating layer is then removed with a chemical solution or the like to form the desired wiring layer.

[0104] Furthermore, holes such as via holes may be formed in the resin layer as needed, and the method for forming the holes is not particularly limited and any conventionally known method can be used, such as an NC drill, a carbon dioxide laser, a UV laser, a YAG laser, or plasma.

[0105] [Metal-clad laminate] The laminate of the present embodiment described above may be in the form of a plate or may be a flexible laminate having flexibility. The laminate of this embodiment may be a metal-clad laminate. The metal-clad laminate is obtained by laminating the resin composition of the present embodiment or the prepreg of the present embodiment and a metal foil, followed by curing, and a portion of the metal foil is removed from the metal-clad laminate. The metal-clad laminate preferably has a configuration in which a cured prepreg (also referred to as a "cured composite") and a metal foil are laminated and adhered together, and is suitably used as a material for electronic circuit boards.

[0106] Examples of metal foils include aluminum foil and copper foil, and among these, copper foil is preferred because of its low electrical resistance. The cured prepreg to be combined with the metal foil may be one or more sheets, and depending on the application, the metal foil is laminated on one or both sides of the cured product to form a metal-clad laminate. Examples of methods for producing the metal-clad laminate include a method in which a prepreg composed of the resin composition of the present embodiment and a substrate is formed, this is layered on a metal foil, and the resin composition is then cured to obtain a metal-clad laminate in which the cured prepreg and the metal foil are laminated together. One particularly preferred application of the metal-clad laminate is a printed wiring board. The printed wiring board is preferably produced by removing at least a portion of the metal foil from the metal-clad laminate. That is, in such a case, the metal-clad laminate serves as an intermediate product for the printed wiring board. The printed wiring board can be produced by a pressure-heat molding method using the prepreg of the present embodiment described above. The substrate can be the same as the substrate of the prepreg described above. By including the resin composition of the present embodiment, the printed wiring board has excellent strength and electrical properties (low dielectric constant and low dielectric loss tangent), and can suppress fluctuations in electrical properties due to environmental changes, and has excellent insulation reliability and mechanical properties.

[0107] [Materials for electronic circuit boards, printed wiring boards] The material for an electronic circuit board of this embodiment includes a cured product of the resin composition of this embodiment. The material for an electronic circuit board of this embodiment can be produced using the resin composition and / or varnish of this embodiment described above. The material for electronic circuit boards of this embodiment includes at least one selected from the group consisting of a cured product of the resin composition described above, a resin film containing the resin composition of this embodiment or a cured product thereof, and a prepreg which is a composite of a substrate and the resin composition. The material for electronic circuit boards of this embodiment can be used, for example, as a printed wiring board having a resin-coated metal foil. [Example]

[0108] Hereinafter, the present embodiment will be described in detail with reference to specific examples and comparative examples, but the present invention is not limited to the following examples and comparative examples in any way.

[0109] The methods for identifying the structure and measuring the physical properties of the hydrogenated conjugated diene copolymer or the unhydrogenated conjugated diene copolymer (component (I)) (hereinafter sometimes referred to as the conjugated diene copolymer) in the following Examples and Comparative Examples are shown below.

[0110] [Methods for identifying the structure of conjugated diene copolymers and measuring their physical properties] ((1) Content of vinyl aromatic monomer units in conjugated diene copolymers) Before hydrogenation, the conjugated diene copolymer was used and the content of vinyl aromatic monomer units in the copolymer was measured using an ultraviolet spectrophotometer (Shimadzu Corporation, UV-2450).

[0111] ((2) Vinyl bond content of conjugated diene copolymer) The vinyl bond amount of the conjugated diene copolymer before hydrogenation was measured using an infrared spectrophotometer (manufactured by JASCO Corporation, FT / IR-230). The vinyl bond content of the copolymer was calculated by the Hampton method.

[0112] ((3) Molecular weight and molecular weight distribution of conjugated diene copolymer) The molecular weight of the conjugated diene copolymer (I) before modification and hydrogenation was measured by GPC (apparatus: LC-10 (Shimadzu Corporation), column: TSKgel GMHXL (4.6 mm x 30 cm)). The solvent used was tetrahydrofuran. The measurement was carried out at a temperature of 35°C. The molecular weight is a weight average molecular weight determined by using the molecular weight of the peak in the chromatogram and a calibration curve (prepared using the peak molecular weight of the standard polystyrene) determined from the measurement of commercially available standard polystyrene. When there are multiple peaks in the chromatogram, the molecular weight is the average molecular weight calculated from the molecular weight of each peak and the composition ratio of each peak (calculated from the area ratio of each peak in the chromatogram). The molecular weight distribution is the ratio (Mw / Mn) of the obtained weight average molecular weight (Mw) to the number average molecular weight (Mn).

[0113] ((4) Hydrogenation rate of double bonds of conjugated diene monomer units of conjugated diene copolymer) Component (I) after hydrogenation: The hydrogenated conjugated diene copolymer was used and the hydrogenation rate of the double bonds of the conjugated diene monomer units was measured using a nuclear magnetic resonance spectrometer (manufactured by BRUKER, DPX-400).

[0114] [Hydrogenated or non-hydrogenated conjugated diene copolymers (sometimes collectively referred to as conjugated diene copolymers), materials for resin compositions] (Preparation of hydrogenation catalyst) In the Production Examples and Comparative Production Examples described below, the hydrogenation catalyst used in producing the hydrogenated conjugated diene copolymers was prepared by the following method. A reaction vessel equipped with a stirrer was purged with nitrogen, and 1 liter of dried and purified cyclohexane was placed in the vessel. Next, 100 mmol of bis(η5-cyclopentadienyl)titanium dichloride was added. While thoroughly stirring, an n-hexane solution containing 200 mmol of trimethylaluminum was added, and the reaction was carried out at room temperature for about 3 days. This produced a hydrogenation catalyst.

[0115] (Component (I): Conjugated diene copolymer) A conjugated diene copolymer of a vinyl aromatic compound and a conjugated diene compound was prepared as follows. The structures and physical properties of each conjugated diene copolymer are shown in Tables 1 to 3.

[0116] <(Production Example 1) Hydrogenated Conjugated Diene Copolymer (1)> Batch polymerization was carried out using a tank-type reactor (internal volume: 10 L) equipped with a stirrer and a jacket. First, a cyclohexane solution (concentration: 20% by mass) containing 10 parts by mass of styrene and 90 parts by mass of butadiene was added. Next, 2.14 parts by mass of n-butyllithium relative to 100 parts by mass of the total monomers and 0.35 mol of tetramethylethylenediamine (TMEDA) relative to 1 mol of n-butyllithium were added, and polymerization was carried out at 70° C. for 20 minutes. Thereafter, methanol was added to terminate the polymerization reaction, thereby obtaining a conjugated diene copolymer. The conjugated diene copolymer obtained as described above had a styrene content of 10% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, and the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%. The obtained conjugated diene copolymer was further added with the hydrogenation catalyst prepared as described above in an amount of 90 ppm (Ti basis) per 100 parts by mass of the copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.7 MPa and a temperature of 80°C for approximately 0.5 hours to obtain a hydrogenated conjugated diene copolymer (1). The hydrogenation rate of the obtained hydrogenated conjugated diene copolymer (1) was 50%.

[0117] <(Production Example 2): Hydrogenated Conjugated Diene Copolymer (2)> The same operations as in the production of hydrogenated conjugated diene copolymer (1) were carried out, except that 20 parts by mass of styrene and 80 parts by mass of butadiene were added. The hydrogenated conjugated diene copolymer (2) obtained as described above had a styrene content of 20% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%, and the hydrogenation rate was 51%.

[0118] <(Production Example 3): Hydrogenated Conjugated Diene Copolymer (3)> The same operation as in the hydrogenated conjugated diene copolymer (1) was carried out, except that 40 parts by mass of styrene and 60 parts by mass of butadiene were added, 1.8 parts by mass of n-butyllithium per 100 parts by mass of the total monomers, and 0.18 mol of TMEDA per 1 mol of n-butyllithium were added. The hydrogenated conjugated diene copolymer (3) obtained as described above had a styrene content of 40% by mass and a weight-average molecular weight of 0.5×10 4The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 54%, and the hydrogenation rate was 49%.

[0119] <(Production Example 4): Hydrogenated Conjugated Diene Copolymer (4)> The same operation as in the hydrogenated conjugated diene copolymer (1) was carried out, except that 60 parts by mass of styrene and 40 parts by mass of butadiene were added, 1.56 parts by mass of n-butyllithium per 100 parts by mass of the total monomers, and 0.19 mol of TMEDA per 1 mol of n-butyllithium were added. The hydrogenated conjugated diene copolymer (4) obtained as described above had a styrene content of 60% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%, and the hydrogenation rate was 50%.

[0120] <(Production Example 5): Hydrogenated Conjugated Diene Copolymer (5)> The same operation as in the hydrogenated conjugated diene copolymer (1) was carried out, except that 85 parts by mass of styrene and 15 parts by mass of butadiene were added, 1.28 parts by mass of n-butyllithium per 100 parts by mass of the total monomers, and 0.24 mol of TMEDA per 1 mol of n-butyllithium were added. The hydrogenated conjugated diene copolymer (5) obtained as described above had a styrene content of 85% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 56%, and the hydrogenation rate was 52%.

[0121] <(Production Example 6) Hydrogenated Conjugated Diene Copolymer (6)> The same procedure as in the hydrogenated conjugated diene copolymer (2) was carried out, except that 0.67 parts by mass of n-butyllithium was added per 100 parts by mass of the total monomers, and 0.33 mol of TMEDA was added per 1 mol of n-butyllithium. The hydrogenated conjugated diene copolymer (6) obtained as described above had a styrene content of 20% by mass and a weight-average molecular weight of 1.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 54%, and the hydrogenation rate was 50%.

[0122] <(Production Example 7): Hydrogenated Conjugated Diene Copolymer (7)> The same procedure as in the hydrogenated conjugated diene copolymer (2) was carried out, except that 0.51 parts by mass of n-butyllithium was added per 100 parts by mass of the total monomers, and 0.37 mol of TMEDA was added per 1 mol of n-butyllithium. The hydrogenated conjugated diene copolymer (7) obtained as described above had a styrene content of 20% by mass and a weight average molecular weight of 2.0×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%, and the hydrogenation rate was 50%.

[0123] <(Production Example 8): Hydrogenated Conjugated Diene Copolymer (8)> The same procedure as in the hydrogenated conjugated diene copolymer (2) was carried out, except that 0.34 parts by mass of n-butyllithium was added per 100 parts by mass of the total monomers, and 0.44 mol of TMEDA was added per 1 mol of n-butyllithium. The hydrogenated conjugated diene copolymer (8) obtained as described above had a styrene content of 20% by mass and a weight average molecular weight of 3.0×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%, and the hydrogenation rate was 50%.

[0124] <(Production Example 9): Hydrogenated Conjugated Diene Copolymer (9)> The same procedure as in the hydrogenated conjugated diene copolymer (2) was carried out, except that the hydrogenation reaction time was changed to 0.15 hours. The hydrogenated conjugated diene copolymer (9) obtained as described above had a styrene content of 20% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%, and the hydrogenation rate was 11%.

[0125] <(Production Example 10): Hydrogenated Conjugated Diene Copolymer (10)> The same procedure as in the preparation of hydrogenated conjugated diene copolymer (2) was carried out, except that the hydrogenation reaction time was changed to 0.25 hours. The hydrogenated conjugated diene copolymer (10) obtained as described above had a styrene content of 20% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%, and the hydrogenation rate was 35%.

[0126] <(Production Example 11): Hydrogenated Conjugated Diene Copolymer (11)> The same procedure as in the hydrogenated conjugated diene copolymer (2) was carried out, except that the hydrogenation reaction time was changed to 0.75 hours. The hydrogenated conjugated diene copolymer (11) obtained as described above had a styrene content of 20% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%, and the hydrogenation rate was 85%.

[0127] <(Production Example 12): Hydrogenated Conjugated Diene Copolymer (12)> The same procedure as in the preparation of hydrogenated conjugated diene copolymer (2) was carried out, except that the hydrogenation reaction time was 1.00 hour. The hydrogenated conjugated diene copolymer (12) obtained as described above had a styrene content of 20% by mass and a weight-average molecular weight of 0.5×10 4The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%, and the hydrogenation rate was 100%.

[0128] <(Production Example 13): Hydrogenated Conjugated Diene Copolymer (13)> The same procedure as in the hydrogenated conjugated diene copolymer (2) was carried out, except that the amount of TMEDA was 0.43 mol per 1 mol of n-butyllithium and the hydrogenation reaction time was 0.25 hours. The hydrogenated conjugated diene copolymer (13) obtained as described above had a styrene content of 40% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 76%, and the hydrogenation rate was 35%.

[0129] <(Production Example 14): Hydrogenated Conjugated Diene Copolymer (14)> The same procedure as in the hydrogenated conjugated diene copolymer (2) was carried out, except that the amount of TMEDA was 0.06 mol per 1 mol of n-butyllithium and the hydrogenation reaction time was 0.25 hours. The hydrogenated conjugated diene copolymer (14) obtained as described above had a styrene content of 20% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 21%, and the hydrogenation rate was 36%.

[0130] <(Production Example 15) Hydrogenated Conjugated Diene Copolymer (15)> The same procedure as in the hydrogenated conjugated diene copolymer (2) was carried out, except that the amount of TMEDA was 0.41 mol per 1 mol of n-butyllithium and the hydrogenation reaction time was 0.25 hours. The hydrogenated conjugated diene copolymer (15) obtained as described above had a styrene content of 20% by mass and a weight-average molecular weight of 0.5×10 4The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 75%, and the hydrogenation rate was 35%.

[0131] <(Production Example 16): Hydrogenated Conjugated Diene Copolymer (16)> The same procedure as in the hydrogenated conjugated diene copolymer (2) was carried out, except that 0.41 mol of TMEDA was added per 1 mol of n-butyllithium. The hydrogenated conjugated diene copolymer (16) obtained as described above had a styrene content of 20% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 75%, and the hydrogenation rate was 50%.

[0132] <(Production Example 17): Hydrogenated Conjugated Diene Copolymer (17)> The same procedure as in the hydrogenated conjugated diene copolymer (16) was carried out, except that the hydrogenation reaction time was changed to 0.75 hours. The hydrogenated conjugated diene copolymer (17) obtained as described above had a styrene content of 20% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 75%, and the hydrogenation rate was 86%.

[0133] <(Production Example 18): Hydrogenated Conjugated Diene Copolymer (18)> The same procedure as in the hydrogenated conjugated diene copolymer (2) was carried out, except that 0.45 mol of TMEDA was added per 1 mol of n-butyllithium and the polymerization temperature was set to 60°C. The hydrogenated conjugated diene copolymer (18) obtained as described above had a styrene content of 20% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 84%, and the hydrogenation rate was 51%.

[0134] <(Production Example 19): Hydrogenated Conjugated Diene Copolymer (19)> The same procedure as in the hydrogenated conjugated diene copolymer (2) was carried out, except that 0.99 parts by mass of n-butyllithium was added relative to 100 parts by mass of the total monomers, and 0.45 mol of TMEDA was added relative to 1 mol of n-butyllithium. The hydrogenated conjugated diene copolymer (19) obtained as described above had a styrene content of 20% by mass and a weight-average molecular weight of 1.0×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 74%, and the hydrogenation rate was 50%.

[0135] <(Production Example 20): Hydrogenated Conjugated Diene Copolymer (20)> The same procedure as in the preparation of hydrogenated conjugated diene copolymer (4) was carried out, except that the hydrogenation reaction time was changed to 0.15 hours. The hydrogenated conjugated diene copolymer (20) obtained as described above had a styrene content of 60% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%, and the hydrogenation rate was 11%.

[0136] <(Production Example 21): Hydrogenated Conjugated Diene Copolymer (21)> The same procedure as in the preparation of hydrogenated conjugated diene copolymer (4) was carried out, except that the hydrogenation reaction time was changed to 0.80 hours. The hydrogenated conjugated diene copolymer (21) obtained as described above had a styrene content of 60% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%, and the hydrogenation rate was 90%.

[0137] <(Production Example 22) Hydrogenated Conjugated Diene Copolymer (22)> Batch polymerization was carried out using a tank-type reactor (internal volume: 10 L) equipped with a stirrer and a jacket. First, a cyclohexane solution (concentration: 20% by mass) containing 30 parts by mass of styrene and 70 parts by mass of butadiene was added. Next, 1.94 parts by mass of n-butyllithium relative to 100 parts by mass of the total monomers and 0.35 mol of tetramethylethylenediamine (TMEDA) relative to 1 mol of n-butyllithium were added, and polymerization was carried out at 70° C. for 20 minutes. Thereafter, methanol was added to terminate the polymerization reaction, thereby obtaining a conjugated diene copolymer. The conjugated diene copolymer obtained as described above had a styrene content of 30% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, and the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%. The obtained conjugated diene copolymer was further added with the hydrogenation catalyst prepared as described above in an amount of 90 ppm (Ti standard) per 100 parts by mass of the conjugated diene copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.7 MPa and a temperature of 80°C for approximately 0.5 hours to obtain a hydrogenated conjugated diene copolymer (22). The hydrogenation rate of the obtained hydrogenated conjugated diene copolymer (22) was 50%.

[0138] <(Production Example 23) Hydrogenated Conjugated Diene Copolymer (23)> Batch polymerization was carried out using a tank-type reactor (internal volume: 10 L) equipped with a stirrer and a jacket. First, a cyclohexane solution (concentration: 20% by mass) containing 70 parts by mass of styrene and 30 parts by mass of butadiene was added. Next, 1.46 parts by mass of n-butyllithium relative to 100 parts by mass of the total monomers and 0.35 mol of tetramethylethylenediamine (TMEDA) relative to 1 mol of n-butyllithium were added, and polymerization was carried out at 70° C. for 20 minutes. Thereafter, methanol was added to terminate the polymerization reaction, thereby obtaining a conjugated diene copolymer. The conjugated diene copolymer obtained as described above had a styrene content of 70% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, and the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%. The obtained conjugated diene copolymer was further added with the hydrogenation catalyst prepared as described above in an amount of 90 ppm (Ti) per 100 parts by mass of the conjugated diene copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.7 MPa and a temperature of 80°C for approximately 0.4 hours to obtain a hydrogenated conjugated diene copolymer (23). The hydrogenation rate of the obtained hydrogenated conjugated diene copolymer (23) was 20%.

[0139] <(Production Example 24): Hydrogenated Conjugated Diene Copolymer (24)> The same procedure as in the preparation of the hydrogenated conjugated diene copolymer (23) was carried out, except that the hydrogenation reaction time was changed to 0.70 hours. The hydrogenated conjugated diene copolymer (24) obtained as described above had a styrene content of 70% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%, and the hydrogenation rate was 80%.

[0140] <(Production Example 25): Hydrogenated Conjugated Diene Copolymer (25)> The same procedure as in the preparation of the hydrogenated conjugated diene copolymer (23) was carried out, except that the hydrogenation reaction time was changed to 0.75 hours. The hydrogenated conjugated diene copolymer (25) obtained as described above had a styrene content of 70% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 56%, and the hydrogenation rate was 90%.

[0141] <(Production Example 26): Hydrogenated Conjugated Diene Copolymer (26)> The same procedure as in the preparation of the hydrogenated conjugated diene copolymer (23) was carried out, except that the hydrogenation reaction time was changed to 0.15 hours. The hydrogenated conjugated diene copolymer (26) obtained as described above had a styrene content of 70% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 56%, and the hydrogenation rate was 10%.

[0142] <(Production Example 27): Hydrogenated Conjugated Diene Copolymer (27)> The same procedure as in the preparation of hydrogenated conjugated diene copolymer (3) was carried out, except that the hydrogenation reaction time was changed to 0.80 hours. The hydrogenated conjugated diene copolymer (27) obtained as described above had a styrene content of 40% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%, and the hydrogenation rate was 90%.

[0143] <(Production Example 28): Hydrogenated Conjugated Diene Copolymer (28)> The same procedure as in the hydrogenated conjugated diene copolymer (3) was carried out, except that the hydrogenation reaction time was changed to 0.15 hours. The hydrogenated conjugated diene copolymer (28) obtained as described above had a styrene content of 40% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 56%, and the hydrogenation rate was 9%.

[0144] <(Production Example 29): Hydrogenated Conjugated Diene Copolymer (29)> The same procedure as in the preparation of the hydrogenated conjugated diene copolymer (29) was carried out, except that 0.49 parts by mass of n-butyllithium was added relative to 100 parts by mass of the total monomers. The hydrogenated conjugated diene copolymer (29) obtained as described above had a styrene content of 60% by mass and a weight-average molecular weight of 1.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%, and the hydrogenation rate was 50%.

[0145] <(Production Example 30): Hydrogenated Conjugated Diene Copolymer (30)> The same procedure as in the production of the hydrogenated conjugated diene copolymer (30) was carried out, except that 0.26 parts by mass of n-butyllithium was added relative to 100 parts by mass of the total monomers. The hydrogenated conjugated diene copolymer (30) obtained as described above had a styrene content of 60% by mass and a weight average molecular weight of 3.0×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%, and the hydrogenation rate was 55%.

[0146] <(Production Example 31): Hydrogenated Conjugated Diene Copolymer (31)> The same procedure as in the preparation of the hydrogenated conjugated diene copolymer (29) was carried out, except that 0.60 mol of TMEDA was added per 1 mol of n-butyllithium and the polymerization temperature was set to 60°C. The hydrogenated conjugated diene copolymer (31) obtained as described above had a styrene content of 60% by mass and a weight-average molecular weight of 1.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 76%, and the hydrogenation rate was 50%.

[0147] <(Production Example 32): Hydrogenated Conjugated Diene Copolymer (32)> The same procedure as in the preparation of the hydrogenated conjugated diene copolymer (29) was carried out, except that 1.56 parts by mass of n-butyllithium was added relative to 100 parts by mass of the total monomers, and the hydrogenation reaction time was 0.75 hours. The hydrogenated conjugated diene copolymer (32) obtained as described above had a styrene content of 60% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 54%, and the hydrogenation rate was 82%.

[0148] <(Production Example 33): Hydrogenated Conjugated Diene Copolymer (33)> The same procedure as in the preparation of hydrogenated conjugated diene copolymer (32) was carried out, except that the hydrogenation reaction time was changed to 0.20 hours. The hydrogenated conjugated diene copolymer (33) obtained as described above had a styrene content of 60% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%, and the hydrogenation rate was 18%.

[0149] <(Production Example 34): Hydrogenated Conjugated Diene Copolymer (34)> The same procedure as in the preparation of hydrogenated conjugated diene copolymer (24) was carried out, except that the hydrogenation reaction time was changed to 0.50 hours. The hydrogenated conjugated diene copolymer (34) obtained as described above had a styrene content of 70% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 56%, and the hydrogenation rate was 55%.

[0150] <(Comparative Production Example 1): Conjugated Diene Copolymer (35)> The same procedure as in the case of the conjugated diene copolymer (2) was carried out, except that the hydrogenation reaction was not carried out. The conjugated diene copolymer (35) obtained as described above had a styrene content of 20% by mass and a weight-average molecular weight of 0.5×10 4The molecular weight distribution was 1.10, and the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 54%.

[0151] <(Comparative Production Example 2) Hydrogenated Conjugated Diene Copolymer (36)> The same procedure as in the hydrogenated conjugated diene copolymer (2) was carried out, except that 0.21 parts by mass of n-butyllithium was added per 100 parts by mass of the total monomers, and 0.34 mol of TMEDA was added per 1 mol of n-butyllithium. The hydrogenated conjugated diene copolymer (36) obtained as described above had a styrene content of 20% by mass and a weight-average molecular weight of 4.0×10 4 The molecular weight distribution was 1.10, the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%, and the hydrogenation rate was 50%.

[0152] <(Comparative Production Example 3): Hydrogenated Conjugated Diene Block Copolymer (37)> Batch polymerization was carried out using a tank-type reactor (internal volume: 10 L) equipped with a stirrer and a jacket. First, a cyclohexane solution containing 10 parts by mass of styrene (concentration: 20% by mass) was added. Next, 2.14 parts by mass of n-butyllithium relative to 100 parts by mass of the total monomers and 0.35 mol of tetramethylethylenediamine (TMEDA) relative to 1 mol of n-butyllithium were added, and polymerization was carried out at 70° C. for 10 minutes. Next, a cyclohexane solution (concentration: 20% by mass) containing 10 parts by mass of styrene and 80 parts by mass of butadiene was added and polymerization was carried out at 70° C. for 30 minutes. Thereafter, methanol was added to terminate the polymerization reaction, thereby obtaining a conjugated diene block copolymer. The conjugated diene block copolymer (37) obtained as described above had a styrene content of 20% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, and the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%. The obtained conjugated diene block copolymer was further added with the hydrogenation catalyst prepared as described above in an amount of 90 ppm (Ti) per 100 parts by mass of the conjugated diene block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.7 MPa and a temperature of 80°C for about 0.5 hours to obtain a hydrogenated conjugated diene block copolymer (37). The hydrogenation rate of the obtained hydrogenated conjugated diene block copolymer was 50%.

[0153] <(Comparative Production Example 4): Hydrogenated Conjugated Diene Block Copolymer (38)> Batch polymerization was carried out using a tank-type reactor (internal volume: 10 L) equipped with a stirrer and a jacket. First, a cyclohexane solution containing 20 parts by mass of butadiene (concentration: 20% by mass) was added. Next, 2.14 parts by mass of n-butyllithium relative to 100 parts by mass of the total monomers and 0.35 mol of tetramethylethylenediamine (TMEDA) relative to 1 mol of n-butyllithium were added, and polymerization was carried out at 70° C. for 10 minutes. Next, a cyclohexane solution (concentration: 20% by mass) containing 20 parts by mass of styrene and 60 parts by mass of butadiene was added and polymerization was carried out at 70° C. for 25 minutes. Thereafter, methanol was added to terminate the polymerization reaction, thereby obtaining a conjugated diene block copolymer. The conjugated diene block copolymer (38) obtained as described above had a styrene content of 20% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, and the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%. The obtained conjugated diene block copolymer was further added with the hydrogenation catalyst prepared as described above in an amount of 90 ppm (Ti) per 100 parts by mass of the conjugated diene block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.7 MPa and a temperature of 80°C for about 0.5 hours to obtain a hydrogenated conjugated diene block copolymer (38). The hydrogenation rate of the obtained hydrogenated conjugated diene block copolymer was 50%.

[0154] <(Comparative Production Example 5): Hydrogenated Conjugated Diene Block Copolymer (39)> Batch polymerization was carried out using a tank-type reactor (internal volume: 10 L) equipped with a stirrer and a jacket. First, a cyclohexane solution containing 20 parts by mass of styrene (concentration: 20% by mass) was added. Next, 2.14 parts by mass of n-butyllithium relative to 100 parts by mass of the total monomers and 0.35 mol of tetramethylethylenediamine (TMEDA) relative to 1 mol of n-butyllithium were added, and polymerization was carried out at 70° C. for 15 minutes. Next, a cyclohexane solution (concentration: 20% by mass) containing 60 parts by mass of butadiene was added and polymerization was carried out at 70° C. for 25 minutes. Next, a cyclohexane solution (concentration: 20% by mass) containing 20 parts by mass of styrene was added and polymerization was carried out at 70° C. for 15 minutes. Thereafter, methanol was added to terminate the polymerization reaction, thereby obtaining a conjugated diene block copolymer. The conjugated diene block copolymer (39) obtained as described above had a styrene content of 40% by mass and a weight-average molecular weight of 0.5×10 4 The molecular weight distribution was 1.10, and the content of units (a) derived from 1,2-bonds and / or 3,4-bonds (vinyl bond amount: units (a) / butadiene) was 55%. The obtained conjugated diene block copolymer was further added with the hydrogenation catalyst prepared as described above in an amount of 90 ppm (Ti) per 100 parts by mass of the conjugated diene block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.7 MPa and a temperature of 80°C for about 0.5 hours to obtain a hydrogenated conjugated diene block copolymer (39). The hydrogenation rate of the obtained hydrogenated conjugated diene block copolymer was 50%.

[0155] Septon 8007 (manufactured by Kuraray Co., Ltd., weight average molecular weight 83,000) was used as the hydrogenated conjugated diene copolymer.

[0156] [Table 1]

[0157] [Table 2]

[0158] [Table 3]

[0159] (Component (II): Radical initiator) Perbutyl P-90 (NOF Corporation) Perbutyl C (NOF Corporation) Park Mill D (manufactured by NOF Corporation)

[0160] (Component (III): Polar resin) <Epoxy resin> Bisphenol A epoxy resin EXA-850CRP (DIC Corporation)

[0161] <Polyimide resin> Bis(3-ethyl-5-methyl-4-maleimidophenyl)methane (BMI-70) (K.I. Chemical Co., Ltd.) 4,4'-Bismaleimidodiphenylmethane (BMI-H) (K.I. Chemical Co., Ltd.)

[0162] <Polyphenylene ether resin (PPE resin)> The PPE resin was polymerized as follows. A 1.5-liter jacketed reactor equipped with a sparger at the bottom for introducing oxygen-containing gas, stirring turbine blades and baffles, and a reflux condenser on the vent gas line at the top of the reactor was charged with 0.2512 g of cupric 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, 493.80 g of n-butanol, and 180.0 g of 2,6-dimethylphenol containing 5 mol% 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane. The mass ratio of the solvent used was n-butanol:methanol = 70:30. Next, oxygen was introduced into the reactor via the sparger at a rate of 180 mL / min with vigorous stirring. At the same time, a heat transfer medium was passed through the jacket to maintain the polymerization temperature at 40 °C. The polymerization solution gradually took on the appearance of a slurry. When the polyphenylene ether reached the desired number-average molecular weight, the oxygen-containing gas was stopped being passed through, and the resulting polymerization mixture was heated to 50°C. Hydroquinone (a reagent manufactured by Wako Pure Chemical Industries, Ltd.) was then added in small amounts, and the mixture was kept at 50°C until the slurry-like polyphenylene ether turned white. 720 g of a methanol solution containing 6.5% by mass of 36% hydrochloric acid was then added, followed by filtration and repeated washing with methanol to obtain wet polyphenylene ether. The mixture was then vacuum-dried at 100°C to obtain dry polyphenylene ether. The ηsp / c was 0.103 dL / g, and the yield was 97%. The ηsp / c was measured by preparing a 0.5 g / dl chloroform solution of the polyphenylene ether and determining the reduced viscosity (ηsp / c) at 30° C. using an Ubbelohde viscometer. The unit is dl / g. The resulting polyphenylene ether was modified as follows. 152.5 g of polyphenylene ether and 152.5 g of toluene were mixed and heated to approximately 85°C. 2.1 g of dimethylaminopyridine was then added. Once all solids had dissolved, 18.28 g of methacrylic anhydride was slowly added. The resulting solution was maintained at 85°C for 3 hours with continuous mixing. The solution was then cooled to room temperature to obtain a toluene solution of methacrylate-capped polyphenylene ether. 1000 mL of 10°C methanol was added dropwise to the resulting toluene solution in a 3-L cylindrical stainless steel vessel equipped with a homogenizer for stirring. The resulting powder was filtered, washed with methanol, and dried at 85°C under nitrogen for 18 hours.

[0163] <Phenoxy resin> YP-50S (Nippon Steel Chemicals Co., Ltd.)

[0164] (Component (IV): Curing agent) Cyanate ester curing agent: 2,2-bis(4-cyanatephenyl)propane (Tokyo Chemical Industry Co., Ltd.) Diamine curing agent: 4,4'-diaminodiphenylmethane (Tokyo Chemical Industry Co., Ltd.) 1-benzyl-2-phenylimidazole (Tokyo Chemical Industry Co., Ltd.) Phenolic hardener KA-1163 (DIC Corporation) Triallyl isocyanurate (TAIC TM ) (Mitsubishi Chemical Corporation)

[0165] [Method for measuring physical properties of resin composition] ((1) Dielectric loss tangent and dielectric constant) The dielectric loss tangent at 10 GHz was measured by the cavity resonance method. The measurement devices used were a network analyzer (N5230A, manufactured by Agilent Technologies) and a cavity resonator (Cavity Resornator CP series, manufactured by Kanto Electronics Application Development Co., Ltd.). The measurement sample was a test piece measuring 2.6 mm wide x 80 mm long cut out from the cured film described below. Using the dielectric loss tangent and dielectric constant obtained above, the following examples and comparative examples were evaluated according to the following criteria.

[0166] <Evaluation criteria for Examples 1 to 42 and Comparative Examples 1 to 13> The evaluation was based on the difference in dielectric loss tangent and dielectric constant between Comparative Example 1, which does not contain a conjugated diene copolymer, and each Example or Comparative Example (Comparative Example 1 - each Example or Comparative Example). Dielectric tangent ◎: 0.013 or more ○: 0.010 or more, less than 0.013 △: 0.008 or more, less than 0.010 ×: Less than 0.008 (including equal and negative differences) dielectric constant ◎: 0.41 or higher ○: 0.38 or more, less than 0.41 △: 0.30 or more, less than 0.38 ×: Less than 0.30 (including equal and negative differences)

[0167] <Evaluation criteria for Examples 43 to 58 and Comparative Examples 14 to 25> The evaluation was based on the difference in dielectric loss tangent and dielectric constant between Comparative Example 14, which does not contain a conjugated diene copolymer, and each Example or Comparative Example (Comparative Example 14 - each Example or Comparative Example). Dielectric tangent ◎: 0.0013 or more ○: 0.0011 or more, less than 0.0013 △: 0.0008 or more, less than 0.0011 ×: Less than 0.0008 (including equal and negative differences) dielectric constant ◎: 0.16 or higher ○: 0.14 or more, less than 0.16 △: 0.10 or more, less than 0.14 ×: Less than 0.10 (including equal and negative differences)

[0168] <Evaluation criteria for Examples 59 to 69 and Comparative Examples 26 to 38> The evaluation was based on the difference in dielectric loss tangent and dielectric constant between Comparative Example 26, which does not contain a conjugated diene copolymer, and each Example and Comparative Example (Comparative Example 26 - each Example or Comparative Example). Dielectric tangent ◎: 0.0013 or more ○: 0.0011 or more, less than 0.0013 △: 0.0008 or more, less than 0.0011 ×: Less than 0.0008 (including equal and negative differences) dielectric constant ◎: 0.13 or more ○: 0.11 or more, less than 0.13 △: 0.08 or more, less than 0.11 ×: Less than 0.08 (including equal and negative differences)

[0169] ((2) Strength (tensile strength), toughness (breaking elongation)) A sheet of the cured product made from the resin composition described below was punched into a JIS No. 1 dumbbell and subjected to a tensile test at room temperature at a tensile speed of 1 mm / min to calculate the tensile strength (MPa) and elongation at break (mm). Using the tensile strength and elongation at break obtained above, the following examples and comparative examples were evaluated according to the following criteria.

[0170] <Evaluation criteria for Examples 1 to 42 and Comparative Examples 1 to 13> The evaluation was based on the ratio of tensile strength and elongation at break between Comparative Example 1, which does not contain a conjugated diene copolymer, and each Example or Comparative Example (each Example or Comparative Example / Comparative Example 1). Tensile strength ◎:1.1 times or more ○: 0.8 times or more, less than 1.1 times △: 0.5 times or more and less than 0.8 times ×: Less than 0.5 times Breaking elongation ◎:2.5 times or more ○: 2.0 times or more, less than 2.5 times △: 1.0 times or more, less than 2.0 times ×: Less than 1.0 times

[0171] <Evaluation criteria for Examples 43 to 58 and Comparative Examples 14 to 25> The tensile strength and elongation at break ratio of each Example or Comparative Example to Comparative Example 14, which does not contain a conjugated diene copolymer, was evaluated (each Example or Comparative Example / Comparative Example 14). Tensile strength ◎:1.1 times or more ○: 0.8 times or more, less than 1.1 times △: 0.5 times or more and less than 0.8 times ×: Less than 0.5 times Breaking elongation ◎:2.5 times or more ○: 2.0 times or more, less than 2.5 times △: 1.0 times or more, less than 2.0 times ×: Less than 1.0 times

[0172] <Evaluation criteria for Examples 59 to 69 and Comparative Examples 26 to 38> The tensile strength and elongation at break ratio of each Example or Comparative Example to Comparative Example 26, which does not contain a conjugated diene copolymer, was evaluated (each Example or Comparative Example / Comparative Example 26). Tensile strength ◎:1.1 times or more ○: 0.8 times or more, less than 1.1 times △: 0.5 times or more and less than 0.8 times ×: Less than 0.5 times Breaking elongation ◎:1.5 times or more ○: 1.0 times or more, less than 1.5 times △: 0.8 times or more, less than 1.0 times ×: Less than 0.8 times

[0173] ((3) Storage stability) The varnishes of the Examples and Comparative Examples described below were left to stand at 30°C / 50% RH, and their condition was observed. The number of days until the occurrence of layer separation and / or precipitation of a gel-like component and the presence or absence of such separation were evaluated according to the following criteria. ◎: 120 days or more (including no precipitation) ○: 90 days or more △: 30 days or more ×: Less than 30 days

[0174] [Preparation of Resin Composition] (Examples 1 to 42), (Comparative Examples 1 to 13) The component ratios and physical properties are shown in Tables 4 to 7 below. First, all components except the phenolic curing agent and phenoxy resin were added to toluene, stirred and dissolved to prepare a varnish with a concentration of 20% by mass to 50% by mass. The phenolic curing agent was prepared by preparing a 50% by mass solution using methyl ethyl ketone (special grade product manufactured by Wako Pure Chemical Industries, Ltd., used as is) as a solvent, and adding and stirring the solution to the varnish to prepare a varnish. The phenoxy resin was prepared by preparing a 25% by mass phenoxy resin solution using cyclohexanone (special grade product manufactured by Wako Pure Chemical Industries, Ltd., used as is) as a solvent, adding the solution to the varnish, and stirring to prepare a varnish. The varnish was applied to a release-treated Kapton film at a speed of 30 mm / sec, and then dried in a nitrogen stream in a blower dryer at 100° C. for 30 minutes to obtain a film. The obtained film was subjected to a curing reaction in a nitrogen stream in a blower dryer at 200° C. for 90 minutes to obtain a cured film. The cured film was used as an evaluation sample.

[0175] (Examples 43 to 58), (Comparative Examples 14 to 25) First, a polar polyimide resin and a cyanate ester curing agent and / or a diamine curing agent were dissolved at 160°C in the proportions shown in Tables 8 and 9 below, and the mixture was allowed to react for 6 hours with stirring to obtain a bismaleimide-triazine resin oligomer. The obtained bismaleimide-triazine resin oligomer was dissolved in toluene, and the remaining components were added and stirred to dissolve, to prepare a varnish with a concentration of 20% to 50% by mass. The varnish was applied onto a release-treated Kapton film at a speed of 30 mm / sec. Thereafter, the film was dried in a nitrogen stream at 100° C. for 30 minutes in a blower dryer to obtain a film. The film was subjected to a curing reaction in a nitrogen gas flow in a blower dryer at 200°C for a maximum of 90 minutes to obtain a cured film. The cured film was used as an evaluation sample.

[0176] (Examples 59 to 69), (Comparative Examples 26 to 38) The component ratios and physical properties are shown in Tables 10 and 11 below. First, each component was added to toluene (special grade product manufactured by Wako Pure Chemical Industries, Ltd., used as is), stirred and dissolved to prepare a varnish with a concentration of 20% by mass to 50% by mass. The varnish was applied to a release-treated Kapton film at a speed of 30 mm / sec, and then dried in a nitrogen stream at 100°C for 30 minutes to obtain a film. The resulting film was cured in a nitrogen stream at 200°C for 90 minutes to obtain a cured film. The cured film was used as an evaluation sample.

[0177] It was found that the cured products using the hydrogenated conjugated diene copolymers of the Examples have an excellent balance of dielectric properties and strength. The cured products of the present invention are suitable for printed wiring boards using glass cloth and metal laminates.

[0178] [Table 4]

[0179] [Table 5]

[0180] [Table 6]

[0181] [Table 7]

[0182] [Table 8]

[0183] [Table 9]

[0184] [Table 10]

[0185] [Table 11]

[0186] This application is based on a Japanese patent application (Patent Application No. 2022-081444) filed with the Japan Patent Office on May 18, 2022, the contents of which are incorporated herein by reference. [Industrial Applicability]

[0187] The hydrogenated conjugated diene copolymer, resin composition, and cured product of the present invention have industrial applicability as materials for films, prepregs, electronic circuit boards, and next-generation communication boards.

Claims

1. Component (I): A hydrogenated conjugated diene copolymer, which is a random copolymer having vinyl aromatic monomer units and conjugated diene monomer units, and which is hydrogenated and has a weight average molecular weight of 35,000 or less; A resin composition containing the following component (III) and at least one component selected from the group consisting of the following components (II) and (IV): Component (II): Radical initiator Component (III): Polar resin (excluding component (I)) Component (IV): Curing agent (excluding component (II)) The resin composition, wherein the component (III) is at least one selected from the group consisting of epoxy resins, polyimide resins, polyphenylene ether resins, liquid crystal polyester resins, and fluorine-containing resins.

2. The hydrogenation rate of the hydrogenated conjugated diene copolymer is 5 to 95%. The resin composition according to claim 1.

3. the conjugated diene copolymer before hydrogenation contains units (a) derived from 1,2-bonds and / or 3,4-bonds and units (b) derived from 1,4-bonds, the content of the units (a) derived from the 1,2-bond and / or the 3,4-bond is 80% or less when the total content of the conjugated diene monomer units is 100%; The resin composition according to claim 1.

4. the conjugated diene copolymer before hydrogenation contains units (a) derived from 1,2-bonds and / or 3,4-bonds and units (b) derived from 1,4-bonds, the content of the units (a) derived from the 1,2-bond and / or the 3,4-bond is 80% or less when the total content of the conjugated diene monomer units is 100%; The resin composition according to claim 2.

5. The hydrogenation rate of the hydrogenated conjugated diene copolymer is 15 to 85%. The resin composition according to claim 1.

6. the content of vinyl aromatic monomer units in the hydrogenated conjugated diene copolymer is 35 to 75 mass%; The resin composition according to claim 1.

7. the component (III) is at least one polar resin selected from the group consisting of epoxy resins, polyimide resins, and polyphenylene ether resins; The component (I) is a hydrogenated conjugated diene copolymer, in which the content of vinyl aromatic monomer units in the hydrogenated conjugated diene copolymer is 35 to 75 mass%. The resin composition according to claim 1.

8. The component (III) is an epoxy resin. The resin composition according to claim 1.

9. A cured product of the resin composition according to claim 1.

10. A resin film comprising the resin composition according to claim 1.

11. A substrate; The resin composition according to claim 1; Prepreg is a composite material.

12. The substrate is a glass cloth. The prepreg according to claim 11.

13. A laminate comprising the resin film according to claim 10 and a metal foil.

14. A cured product of the prepreg according to claim 11, a metal foil, A laminate having:

15. A printed wiring board comprising the cured product according to claim 9.

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