Fluorene compound, resin composition, prepreg, film with resin, metal foil with resin, metal-clad laminate, and wiring board

Abstract

One aspect of the present invention is a fluorene compound represented by formula (1).　In formula (1), R1 and R2 each independently represent a C2-5 alkyl group and R3 and R4 each independently represent at least one of an alkenyl group and a group represented by formula (2).　In formula (2), p represents 0-10, R5 to R7 each independently represent a hydrogen atom or an alkyl group, and Ar represents an arylene group.

Description

Fluorene compound, resin composition, prepreg, resin-coated film, resin-coated metal foil, metal-clad laminate, and wiring board

[0001] The present invention relates to a fluorene compound, a resin composition, a prepreg, a resin-coated film, a resin-coated metal foil, a metal-clad laminate, and a wiring board.

[0002] Examples of the fluorene compound to be added to materials such as resins include the fluorene compounds described in Patent Documents 1 and 2.

[0003] Patent Document 1 describes a fluorene compound having at least one polymerizable unsaturated group per molecule as a fluorene compound contained in a polymerizable composition that is polymerized and cured to obtain a high-frequency substrate. Patent Document 1 discloses that a substrate having excellent dielectric properties, particularly a low dielectric loss tangent, and excellent heat resistance in the high-frequency region can be obtained.

[0004] Patent Document 2 describes a divinylbenzylfluorene compound in which two substituents selected from a halogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group, a thioalkoxy group, an aryl group having 6 to 30 carbon atoms, and a heteroaryl group having 3 to 30 carbon atoms are added to a carbon atom of an aromatic ring in a fluorene structure, and a vinylbenzyl group is added to a carbon atom of a five-membered ring in the fluorene structure. Patent Document 2 discloses that it is possible to provide a novel divinylbenzylfluorene compound with improved properties such as transparency and solubility.

[0005] Materials such as resins are sometimes required to have high flame resistance. For example, materials used in electrical equipment and electronic components are required to have high flame resistance from the perspective of safety, etc. More specifically, substrate materials for constituting insulating layers of wiring boards used in electronic devices are required to have high flame resistance so that electronic components such as semiconductor devices can be used properly even in high-temperature environments. Materials such as resins are also sometimes required to have low dielectric properties such as dielectric dissipation factor. Specifically, such substrate materials are required to have low dielectric properties such as dielectric dissipation factor in order to increase signal transmission speed and reduce signal transmission loss, and substrate materials used for high-frequency wiring boards are even more required to have low dielectric properties. For these reasons, materials added to materials such as resins are required to have excellent flame resistance and low dielectric properties such as dielectric dissipation factor.

[0006] JP 2003-283076 A JP 2022-167558 A

[0007] The present invention has been made in view of the above circumstances, and aims to provide a fluorene compound having a low relative dielectric constant and dielectric loss tangent and excellent flame resistance. The present invention also aims to provide a resin composition containing the fluorene compound, and a prepreg, a resin-coated film, a resin-coated metal foil, a metal-clad laminate, and a wiring board obtained using the resin composition.

[0008] One aspect of the present invention is a fluorene compound represented by the following formula (1):

[0009] In formula (1), R １ and R ２ each independently represents an alkyl group having 2 to 5 carbon atoms; R ３ and R ４ each independently represents at least one of an alkenyl group and a group represented by the following formula (2):

[0010] In formula (2), p represents 0 to 10, and R ５ ~R ７each independently represents a hydrogen atom or an alkyl group, and Ar represents an arylene group.

[0011] These and other objects, features, and advantages of the present invention will become apparent from the following detailed description and the accompanying drawings.

[0012] Fig. 1 is a schematic cross-sectional view showing an example of a prepreg according to an embodiment of the present invention. Fig. 2 is a schematic cross-sectional view showing an example of a metal-clad laminate according to an embodiment of the present invention. Fig. 3 is a schematic cross-sectional view showing an example of a wiring board according to an embodiment of the present invention. Fig. 4 is a schematic cross-sectional view showing an example of a resin-coated metal foil according to an embodiment of the present invention. Fig. 5 is a schematic cross-sectional view showing an example of a resin-coated film according to an embodiment of the present invention. Fig. 6 shows an HPLC chart during synthesis of the fluorene compound according to Example 1. Fig. 7 shows a HPLC chart of the fluorene compound according to Example 1. １ 8 shows an HPLC chart during synthesis of the fluorene compound according to Example 2. FIG. 9 shows an HPLC chart during synthesis of the fluorene compound according to Example 2. １ The H-NMR spectrum is shown.

[0013] As a result of various investigations, the present inventors have found that the above object can be achieved by the present invention described below.

[0014] Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to these.

[0015] [Fluorene Compound] The fluorene compound according to the embodiment of the present invention is a fluorene compound represented by the following formula (1).

[0016] In formula (1), R １ and R ２ each independently represents an alkyl group having 2 to 5 carbon atoms; R ３ and R ４ each independently represents at least one of an alkenyl group and a group represented by the following formula (2):

[0017] In formula (2), p represents 0 to 10, and R ５ ~R ７each independently represents a hydrogen atom or an alkyl group, and Ar represents an arylene group.

[0018] The fluorene compound has a low dielectric constant and dielectric dissipation factor and is excellent in flame resistance. This is thought to be due to, for example, the following reasons. As shown in formula (1), the fluorene compound has a fluorene structure and the alkyl group is attached to a carbon atom of a five-membered ring in the fluorene structure (position 9 of the fluorene structure). This allows the low dielectric properties of the fluorene structure to be fully exhibited, and the dielectric constant and dielectric dissipation factor to be sufficiently reduced. Furthermore, as can be seen from formula (1), the fluorene compound has an unsaturated double bond attached to a carbon atom of an aromatic ring in the fluorene structure, allowing the fluorene compound to maintain excellent low dielectric properties while improving flame resistance. In contrast, conventional fluorene compounds have neither an alkyl group having 2 to 5 carbon atoms at position 9 of the fluorene structure nor an unsaturated double bond attached to a carbon atom of an aromatic ring in the fluorene structure. For example, when the fluorene compound described in Patent Document 2 has an unsaturated double bond such as a vinylbenzyl group at the carbon atom of the five-membered ring in the fluorene structure (position 9 of the fluorene structure), the fluorene structure is present in a side chain, which is thought to result in poor flame resistance. Furthermore, since the fluorene structure does not have an alkyl group having 2 to 5 carbon atoms at position 9, it is thought that the low dielectric properties cannot be fully exhibited. Therefore, the fluorene compound has a lower relative dielectric constant and dielectric loss tangent than conventional fluorene compounds, and is a fluorene compound with excellent flame resistance.

[0019] In the formula (1), R １ and R ２ are independent of each other. That is, R １ and R ２ may be the same group or different groups. １ and R ２ represents an alkyl group having 2 to 5 carbon atoms. ３ and R ４ are independent of each other. That is, R ３ and R ４may be the same group or different groups. ３ and R ４ represents at least one of an alkenyl group and a group represented by the following formula (2):

[0020] The alkyl group in the formula (1) is not particularly limited as long as it is an alkyl group having 2 to 5 carbon atoms, and examples thereof include an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, and a pentyl group, etc. Among these, the alkyl group is preferably a butyl group.

[0021] The alkenyl group in the formula (1) is not particularly limited, and examples thereof include alkenyl groups having 2 to 5 carbon atoms. Specific examples of the alkenyl group include a vinyl group, an allyl group, a propenyl group, and a butenyl group, and among these, a vinyl group is preferred.

[0022] In the formula (2), p represents 0 to 10. ５ ~R ７ are independent of each other. That is, R ５ ~R ７ may be the same group or different groups. ５ ~R ７ represents a hydrogen atom or an alkyl group. Ar represents an arylene group.

[0023] In the formula (2), when p is 0, this indicates that Ar (arylene group) is directly bonded to the aromatic ring of the fluorene structure.

[0024] The alkyl group in the formula (2) is not particularly limited, and is preferably, for example, an alkyl group having 1 to 18 carbon atoms, more preferably an alkyl group having 1 to 10 carbon atoms. Specific examples include a methyl group, an ethyl group, a propyl group, a hexyl group, and a decyl group.

[0025] The arylene group in the formula (2) is not particularly limited. Examples of the arylene group include monocyclic aromatic groups such as phenylene groups, and polycyclic aromatic groups in which the aromatic ring is not monocyclic but polycyclic aromatic such as naphthalene rings. The arylene group also includes derivatives in which the hydrogen atom bonded to the aromatic ring is substituted with a functional group such as an alkenyl group, an alkynyl group, a formyl group, an alkylcarbonyl group, an alkenylcarbonyl group, or an alkynylcarbonyl group.

[0026] Preferred specific examples of the group represented by formula (2) include a vinylphenyl group represented by formula (5) below and a vinylbenzyl group (ethenylbenzyl group) represented by formula (6) below, and among these, the vinylphenyl group represented by formula (5) below is preferred. Furthermore, examples of the vinylbenzyl group include an o-ethenylbenzyl group, a p-ethenylbenzyl group, and an m-ethenylbenzyl group.

[0027]

[0028]

[0029] Specific examples of the fluorene compound include a fluorene compound represented by the following formula (3) and a fluorene compound represented by the following formula (4). The fluorene compound may be a fluorene compound represented by the following formula (3) or a fluorene compound represented by the following formula (4), or may be a fluorene compound containing at least one of a fluorene compound represented by the following formula (3) and a fluorene compound represented by the following formula (4).

[0030]

[0031]

[0032] The fluorene compound preferably has a dielectric dissipation factor at a frequency of 1 GHz of 0.00001 to 0.002, more preferably 0.00001 to 0.001, and even more preferably 0.00001 to 0.0005. That is, the fluorene compound is preferably a fluorene compound represented by formula (1) and having a dielectric dissipation factor within the above range. The fluorene compound preferably has a relative dielectric constant at a frequency of 1 GHz of 2 to 3.5, more preferably 2 to 3. That is, the fluorene compound is preferably a fluorene compound represented by formula (1) and having a relative dielectric constant within the above range. The relative dielectric constant and dielectric dissipation factor referred to here are the relative dielectric constant and dielectric dissipation factor at a frequency of 1 GHz, and examples thereof include the relative dielectric constant and dielectric dissipation factor at a frequency of 1 GHz measured by a cavity resonator perturbation method.

[0033] The fluorene compound preferably has a thermal decomposition residue after heating the fluorene compound to 600°C of 26% by mass or more (i.e., 26 to 100% by mass) relative to the fluorene compound before heating. The ratio of the thermal decomposition residue after heating the fluorene compound to the fluorene compound before heating can be measured, for example, by thermogravimetric analysis (TGA), more specifically, by thermogravimetric-differential thermal analysis (TG-DTA), such as the ratio of the residue when the fluorene compound is heated to 600°C relative to the fluorene compound before heating. That is, in thermogravimetric analysis, the weight after heating to 600° C. is preferably 26% or more (ie, 26 to 100%) of the weight before heating.

[0034] The fluorene compound can be added to materials such as resins. The fluorene compound has a low dielectric constant and dielectric dissipation factor and excellent flame resistance. Adding the fluorene compound to a material can lower the dielectric constant and dielectric dissipation factor, thereby improving flame resistance. Therefore, the material to which the fluorene compound is added is not particularly limited, but is preferably a material that is required to lower the dielectric constant and dielectric dissipation factor and improve flame resistance. Examples of materials to which the fluorene compound can be added include materials used in electrical equipment and electronic components, and more specifically, substrate materials for forming insulating layers of wiring boards used in electronic devices. Examples of materials to which the fluorene compound can be added include resins and resin compositions. Such resins and resin compositions are not particularly limited and can be applied in a wide range of applications. The resins and resins contained in the resin compositions may be, for example, thermoplastic resins, thermosetting resins, or mixtures thereof. Examples of the thermosetting resin include epoxy resins, polyphenylene ether resins, cyanate ester resins, phenolic resins, maleimide compounds, modified polyphenylene ether compounds, styrene-based compounds, polybutadiene-based compounds, styrene-butadiene-based compounds, acrylic compounds, methacrylic compounds, and polyfunctional vinyl aromatic copolymers. Examples of the polyfunctional vinyl aromatic copolymer include copolymers containing repeating units derived from a divinyl aromatic compound and repeating units derived from a monovinyl aromatic compound. Examples of the divinyl aromatic compound include divinylbenzene, and examples of the monovinyl aromatic compound include styrene, ethylvinylbenzene, and methylstyrene.Examples of the thermoplastic resin include polyphenylene sulfide resin, liquid crystal polymer, polyethylene resin, polypropylene resin, polystyrene resin, polyurethane resin, acrylonitrile-butadiene-styrene copolymer (ABS resin), acrylic resin, polyethylene terephthalate resin, polycarbonate resin, polyacetal resin, polyimide resin, polyamide-imide resin, cycloolefin polymer, cycloolefin copolymer, and styrene-based elastomer. The resins may be used alone or in combination of two or more. The fluorene compound is preferably used in an insulating material for wiring boards. Specifically, the fluorene compound is preferably contained in a prepreg, a resin layer of a resin-coated metal foil, a resin layer of a resin-coated film, an insulating layer of a metal-clad laminate, and an insulating layer of a wiring board. The insulating material for wiring boards is required to have a low dielectric constant and dielectric loss tangent and excellent flame resistance. As described above, the fluorene compound has a low dielectric constant and dielectric dissipation factor and excellent flame resistance. Adding the fluorene compound to a material reduces the dielectric constant and dielectric dissipation factor, thereby improving flame resistance. Therefore, the fluorene compound is preferably used in wiring board insulating materials. The amount of the fluorene compound added is preferably 5 to 70 parts by mass, more preferably 10 to 50 parts by mass, per 100 parts by mass of the material (the object to which the fluorene compound is added). If the amount of the fluorene compound added is too small, the effect of adding the fluorene compound, i.e., reducing the dielectric constant and dielectric dissipation factor and improving flame resistance, tends to be insufficient. Furthermore, if the amount of the fluorene compound added is too large, the properties of the material (properties other than low dielectric constant and flame resistance) tend to be reduced. Furthermore, even if the fluorene compound is added in an amount greater than a certain amount, the effect of improving flame resistance tends to saturate. Therefore, if the amount of the fluorene compound added is within the above range, it is possible to reduce the relative dielectric constant and dielectric loss tangent, and improve the flame resistance, while suppressing deterioration of the properties of the material.

[0035] [Method for producing fluorene compound] The method for producing the fluorene compound is not particularly limited as long as the fluorene compound can be produced. Specific examples of the method for producing the fluorene compound include a synthesis method using the reaction represented by the following formula (7):

[0036] In formula (7), R １ and R ２ is R in formula (1). １ and R ２ and each independently represents an alkyl group having 2 to 5 carbon atoms. ３ and R ４ is R in formula (1). ３ and R ４ and each independently represents at least one of an alkenyl group and a group represented by formula (2). １ and X ２ each independently represents a halogen atom. Y is -BF ３ K, boronic acid group [—B(OH) ２ ], or a boronic acid ester group.

[0037] The halogen atom is not particularly limited, and examples thereof include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, with a bromine atom being preferred.

[0038] The boronic acid ester group is not particularly limited, and examples thereof include a dioxaborolane group.

[0039] R ３ -Y and R ４ -Y is the same as R ３ and R ４ and the Y bonded thereto, but examples thereof include potassium vinyltrifluoroborate (potassium vinyltrifluoroborate) and 4-vinylphenylboronic acid.

[0040] The catalyst is not particularly limited as long as it is a catalyst that can promote the reaction represented by the formula (7). Examples of the catalyst include a palladium (Pd) catalyst, a nickel (Ni) catalyst, and a ruthenium (Ru) catalyst. The palladium catalyst is not particularly limited as long as it is a palladium catalyst that can promote the reaction represented by the formula (7). Examples of the palladium catalyst include tetrakis(triphenylphosphine)palladium(0) [Pd(PPh ３ ) ４ ], [1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium(II) dichloromethane adduct [PdCl ２ (dppf)], and palladium(II) acetate [Pd(OAc) ２ Examples of the nickel catalyst include [1,1′-bis(diphenylphosphino)ferrocene]dichloronickel(II) [NiCl ２ (dppf)], dichlorobis(triphenylphosphine)nickel(II) [NiCl ２ (PPh ３ ) ２ ], and bis(1,5-cyclooctadiene)nickel(0) [Ni(cod) ２ Among these, examples of the catalyst include tetrakis(triphenylphosphine)palladium(0) [Pd(PPh ３ ) ４ ] is preferred.

[0041] The base is not particularly limited as long as it is a catalyst capable of promoting the reaction represented by formula (7). Examples of the base include carbonate bases such as potassium carbonate, fluoride bases such as cesium fluoride, and amine bases such as tetrabutylammonium hydroxide. Among these, carbonate bases are preferred, and potassium carbonate is more preferred. The base may be used in the form of an aqueous solution.

[0042] The reaction represented by the formula (7) may proceed without using a solvent, or may be carried out in the presence of a solvent. The solvent is not particularly limited as long as it is a solvent that can suitably proceed with the reaction represented by the formula (7). Examples of the solvent include tetrahydrofuran (THF), dimethyl sulfoxide (DMSO), dimethylformamide (DMF), and toluene, and among these, THF is preferred. The solvent may also contain water, and for example, a mixed solvent of THF and water is preferably used. The water may be water contained in the aqueous solution of the base.

[0043] The conditions for the reaction represented by formula (7) are not particularly limited as long as the reaction represented by formula (7) proceeds favorably. For example, the reaction temperature is preferably 50 to 90°C, more preferably 60 to 80°C. The reaction time is preferably 4 to 8 hours, more preferably 4 to 6 hours.

[0044] When the fluorene compound is a fluorene compound represented by formula (3), the fluorene compound can be produced by, for example, a synthesis method using the reaction represented by formula (7) below.

[0045]

[0046] When the fluorene compound is a fluorene compound represented by formula (4), the fluorene compound can be produced by, for example, a synthesis method using the reaction represented by formula (9) below.

[0047]

[0048] [Prepreg, metal-clad laminate, wiring board, resin-coated metal foil, and resin-coated film] By using a resin composition in which the fluorene compound according to this embodiment is added to the thermosetting resin, prepreg, metal-clad laminate, wiring board, resin-coated metal foil, and resin-coated film can be obtained as follows.

[0049] (Prepreg) FIG. 1 is a schematic cross-sectional view showing an example of a prepreg 1 according to an embodiment of the present invention.

[0050] 1, the prepreg 1 according to this embodiment comprises the resin composition or a semi-cured product of the resin composition 2, and a fibrous base material 3. This prepreg 1 comprises the resin composition or a semi-cured product of the resin composition 2, and the fibrous base material 3 present in the resin composition or the semi-cured product of the resin composition 2.

[0051] In this embodiment, the semi-cured product refers to a resin composition that has been partially cured to the extent that it can be further cured. That is, the semi-cured product refers to a resin composition that has been semi-cured (B-staged). For example, when a resin composition is heated, the viscosity initially gradually decreases, and then curing begins, and the viscosity gradually increases. In such a case, the semi-cured state may refer to a state between when the viscosity starts to increase and when the composition is completely cured.

[0052] The prepreg obtained using the resin composition according to this embodiment may comprise a semi-cured product of the resin composition as described above, or may comprise the uncured resin composition itself. That is, it may be a prepreg comprising a semi-cured product of the resin composition (the resin composition in B stage) and a fibrous base material, or a prepreg comprising the resin composition before curing (the resin composition in A stage) and a fibrous base material. Furthermore, the resin composition or the semi-cured product of the resin composition may be the resin composition that has been dried or heat-dried.

[0053] When producing the prepreg, the resin composition 2 is often prepared in a varnish form and used to impregnate the fibrous base material 3, which is a base material for forming the prepreg. That is, the resin composition 2 is usually often a resin varnish prepared in a varnish form. Such a varnish-like resin composition (resin varnish) is prepared, for example, as follows.

[0054] First, each component that is soluble in an organic solvent is added to the organic solvent and dissolved. Heating may be performed as necessary. Then, components that are insoluble in the organic solvent are added as needed, and the mixture is dispersed using a ball mill, bead mill, planetary mixer, roll mill, or the like until a predetermined dispersion state is achieved, thereby preparing a varnish-like resin composition. The organic solvent used here is not particularly limited as long as it dissolves the resin composition and does not inhibit the curing reaction. Specific examples include toluene and methyl ethyl ketone (MEK).

[0055] Specific examples of the fibrous substrate include glass cloth, aramid cloth, polyester cloth, glass nonwoven fabric, aramid nonwoven fabric, polyester nonwoven fabric, pulp paper, and linter paper. Glass cloth can be used to obtain a laminate with excellent mechanical strength, and flattened glass cloth is particularly preferred. A specific example of the flattening process is a method in which glass cloth is continuously pressed with a press roll at an appropriate pressure to compress the yarns flat. The thickness of commonly used fibrous substrates is, for example, 0.01 mm or more and 0.3 mm or less. The glass fibers constituting the glass cloth are not particularly limited, and examples include Q glass, NE glass, E glass, S glass, T glass, L glass, and L2 glass. The surface of the fibrous substrate may be treated with a silane coupling agent. The silane coupling agent is not particularly limited, but examples thereof include silane coupling agents having at least one group selected from the group consisting of a vinyl group, an acryloyl group, a methacryloyl group, a styryl group, an amino group, and an epoxy group in the molecule.

[0056] The method for producing the prepreg is not particularly limited as long as it can produce the prepreg. Specifically, when producing the prepreg, the resin composition according to the present embodiment is often prepared in the form of a varnish, as described above, and used as a resin varnish.

[0057] Specific examples of methods for producing the prepreg 1 include a method in which the resin composition 2, for example, a resin composition 2 prepared in a varnish form, is impregnated into a fibrous substrate 3, followed by drying. The resin composition 2 is impregnated into the fibrous substrate 3 by immersion, coating, or the like. Impregnation can be repeated multiple times as necessary. In this case, by repeating the impregnation using multiple resin compositions with different compositions and concentrations, it is also possible to adjust the final composition and impregnation amount to the desired one.

[0058] The fibrous substrate 3 impregnated with the resin composition (resin varnish) 2 is heated, for example, at 40°C to 180°C for 1 minute to 10 minutes, depending on the desired heating conditions and the resin composition. Prepreg 1 in a pre-cured (A-stage) or semi-cured (B-stage) state is obtained by heating. The organic solvent can be volatilized from the resin varnish by heating, thereby reducing or eliminating the organic solvent.

[0059] (Metal-clad laminate) FIG. 2 is a schematic cross-sectional view showing an example of a metal-clad laminate 11 according to an embodiment of the present invention.

[0060] As shown in FIG. 2 , the metal-clad laminate 11 according to this embodiment includes an insulating layer 12 containing a cured product of the resin composition and a metal foil 13 disposed on the insulating layer 12. Examples of the metal-clad laminate 11 include a metal-clad laminate composed of an insulating layer 12 containing a cured product of the prepreg 1 shown in FIG. 1 and a metal foil 13 laminated together with the insulating layer 12. The insulating layer 12 may be composed of a cured product of the resin composition or a cured product of the prepreg. The thickness of the metal foil 13 varies depending on the performance required of the final wiring board and is not particularly limited. The thickness of the metal foil 13 can be appropriately set depending on the desired purpose, and is preferably, for example, 0.2 to 70 μm. Examples of the metal foil 13 include copper foil and aluminum foil. When the metal foil is thin, it may be a carrier-attached copper foil equipped with a release layer and a carrier to improve handling.

[0061] The method for producing the metal-clad laminate 11 is not particularly limited as long as it can produce the metal-clad laminate 11. Specifically, a method for producing the metal-clad laminate 11 using the prepreg 1 can be used. Examples of such a method include stacking one or more prepregs 1, placing a metal foil 13 such as copper foil on both sides or one side of the prepreg 1, and then heat-pressing and molding the metal foil 13 and the prepreg 1 to form an integrated laminate. That is, the metal-clad laminate 11 can be obtained by laminating the metal foil 13 on the prepreg 1 and then heat-pressing and molding the laminate. The heat-pressing conditions can be appropriately set depending on the thickness of the metal-clad laminate 11, the type of resin composition contained in the prepreg 1, and other factors. While these conditions vary depending on the resin composition, they can be, for example, a temperature of 170 to 230°C, a pressure of 0.5 to 5 MPa, and a time of 60 to 150 minutes. The metal-clad laminate may also be produced without using a prepreg. For example, a method may be used in which a varnish-like resin composition is applied onto a metal foil to form a layer containing the resin composition on the metal foil, and then the layer is heated and pressed.

[0062] (Wiring Board) FIG. 3 is a schematic cross-sectional view showing an example of a wiring board 21 according to an embodiment of the present invention.

[0063] As shown in Fig. 3, wiring board 21 according to this embodiment has insulating layer 12 containing a cured product of the resin composition, and wiring 14 provided on insulating layer 12. Examples of wiring board 21 include a wiring board configured from insulating layer 12 used by curing prepreg 1 shown in Fig. 1, and wiring 14 laminated together with insulating layer 12 and formed by partially removing metal foil 13. Furthermore, insulating layer 12 may be made of a cured product of the resin composition, or may be made of a cured product of the prepreg.

[0064] The method for manufacturing the wiring board 21 is not particularly limited as long as the wiring board 21 can be manufactured. Specific examples include a method of manufacturing the wiring board 21 using the prepreg 1. Examples of this method include a method of manufacturing the wiring board 21 in which wiring is provided as a circuit on the surface of the insulating layer 12 by etching the metal foil 13 on the surface of the metal-clad laminate 11 manufactured as described above. That is, the wiring board 21 is obtained by forming a circuit by partially removing the metal foil 13 on the surface of the metal-clad laminate 11. In addition to the above methods, examples of the method for forming a circuit include circuit formation by a semi-additive process (SAP) or a modified semi-additive process (MSAP).

[0065] (Resin-Coated Metal Foil) FIG. 4 is a schematic cross-sectional view showing an example of a resin-coated metal foil 31 according to this embodiment.

[0066] As shown in Fig. 4, the resin-coated metal foil 31 according to this embodiment comprises a resin layer 32 containing the resin composition or a semi-cured product of the resin composition, and a metal foil 13. The resin-coated metal foil 31 has the metal foil 13 on the surface of the resin layer 32. That is, the resin-coated metal foil 31 comprises the resin layer 32 and the metal foil 13 laminated together with the resin layer 32. The resin-coated metal foil 31 may also comprise another layer between the resin layer 32 and the metal foil 13.

[0067] The resin layer 32 may contain a semi-cured product of the resin composition as described above, or may contain the uncured resin composition. That is, the resin-coated metal foil 31 may comprise a resin layer containing a semi-cured product of the resin composition (the resin composition in B-stage) and a metal foil, or a resin layer containing the resin composition before curing (the resin composition in A-stage) and a metal foil. The resin layer may contain the resin composition or a semi-cured product of the resin composition, and may or may not contain a fibrous substrate. The resin composition or the semi-cured product of the resin composition may be the resin composition that has been dried or heat-dried. The fibrous substrate may be the same as the fibrous substrate of a prepreg.

[0068] The metal foil may be any metal foil used in a metal-clad laminate or a resin-coated metal foil, and examples of the metal foil include copper foil and aluminum foil.

[0069] The resin-coated metal foil 31 may be provided with a cover film or the like as necessary. By providing a cover film, it is possible to prevent the inclusion of foreign matter, etc. The cover film is not particularly limited, but examples thereof include polyolefin films, polyester films, polymethylpentene films, and films formed by providing these films with a release agent layer.

[0070] The method for producing the resin-coated metal foil 31 is not particularly limited as long as it can produce the resin-coated metal foil 31. Examples of methods for producing the resin-coated metal foil 31 include a method of applying the varnish-like resin composition (resin varnish) to the metal foil 13 and heating the applied composition. The varnish-like resin composition is applied to the metal foil 13 using, for example, a bar coater. The applied resin composition is heated, for example, at 40°C or higher and 180°C or lower for 0.1 minutes or longer and 10 minutes or shorter, depending on the resin composition. The heated resin composition is formed on the metal foil 13 as an uncured resin layer 32. The heating volatilizes the organic solvent from the resin varnish, thereby reducing or eliminating the organic solvent.

[0071] (Resin-Coated Film) FIG. 5 is a schematic cross-sectional view showing an example of a resin-coated film 41 according to this embodiment.

[0072] 5 , the resin-coated film 41 according to this embodiment includes a resin layer 42 containing the resin composition or a semi-cured product of the resin composition, and a support film 43. The resin-coated film 41 includes the resin layer 42 and the support film 43 laminated together with the resin layer 42. The resin-coated film 41 may also include another layer between the resin layer 42 and the support film 43.

[0073] The resin layer 42 may contain a semi-cured product of the resin composition as described above, or may contain the uncured resin composition. That is, the resin-coated film 41 may comprise a resin layer containing a semi-cured product of the resin composition (the resin composition in B-stage) and a support film, or a resin-coated film comprising a resin layer containing the resin composition before curing (the resin composition in A-stage) and a support film. The resin layer may contain the resin composition or a semi-cured product of the resin composition, and may or may not contain a fibrous substrate. The resin composition or the semi-cured product of the resin composition may be obtained by drying or heat-drying the resin composition. The fibrous substrate may be the same as the fibrous substrate of a prepreg.

[0074] Any support film used for a resin-coated film can be used without limitation as the support film 43. Examples of the support film include electrically insulating films such as polyester film, polyethylene terephthalate (PET) film, polyimide film, polyparabanic acid film, polyether ether ketone film, polyphenylene sulfide film, polyamide film, polycarbonate film, and polyarylate film.

[0075] The resin-coated film 41 may be provided with a cover film or the like as necessary. By providing a cover film, it is possible to prevent the inclusion of foreign matter, etc. The cover film is not particularly limited, but examples thereof include a polyolefin film, a polyester film, and a polymethylpentene film.

[0076] The support film and the cover film may be subjected to surface treatment such as matte treatment, corona treatment, release treatment, and roughening treatment, if necessary.

[0077] The method for producing the resin-coated film 41 is not particularly limited as long as it can produce the resin-coated film 41. Examples of methods for producing the resin-coated film 41 include a method of applying the varnish-like resin composition (resin varnish) to a support film 43 and heating the resulting film. The varnish-like resin composition is applied to the support film 43 using, for example, a bar coater. The applied resin composition is heated, for example, at 40°C or higher and 180°C or lower for 0.1 minutes or longer and 10 minutes or shorter, depending on the resin composition. The heated resin composition is formed on the support film 43 as an uncured resin layer 42. The heating volatilizes the organic solvent from the resin varnish, thereby reducing or eliminating the organic solvent.

[0078] When a resin composition containing the fluorene compound according to this embodiment is cured, a cured product having a low dielectric constant and dielectric loss tangent and excellent flame resistance is obtained. Therefore, when the prepreg is cured, a cured product having a low dielectric constant and dielectric loss tangent and excellent flame resistance is obtained. The resin-coated metal foil and the resin-coated film are, respectively, resin-coated metal foil and resin-coated film, each having a resin layer that becomes an insulating layer containing the cured product upon curing. The metal-clad laminate and the wiring board are, respectively, metal-clad laminate and wiring board, each having an insulating layer containing the cured product. The prepreg, the resin-coated film, the resin-coated metal foil, and the metal-clad laminate can be suitably used to manufacture the wiring board, and can also be used to manufacture, for example, a multilayer wiring board. For example, a multilayer wiring board can be manufactured by laminating the resin-coated film on a wiring board and then peeling off the support film, or by laminating the resin-coated film on a wiring board after peeling off the support film. The resin-coated metal foil can be, for example, laminated on a wiring board, and then a multilayer wiring board can be manufactured. In this way, by using the resin-coated film and the resin-coated metal foil, etc., it is possible to manufacture a multi-layer wiring board having an insulating layer containing the cured product.

[0079] As described above, this specification discloses various aspects of the technology, the main technologies of which are summarized below.

[0080] The fluorene compound according to the first aspect of the present invention is a fluorene compound represented by the formula (1).

[0081] The fluorene compound according to the second aspect of the present invention is the fluorene compound according to the first aspect of the present invention, wherein the fluorene compound represented by the formula (1) includes at least one of the fluorene compound represented by the formula (3) and the fluorene compound represented by the formula (4).

[0082] The fluorene compound according to the third aspect of the present invention is the fluorene compound according to the first or second aspect of the present invention, wherein the dielectric loss tangent at a frequency of 1 GHz is 0.00001 to 0.001.

[0083] A fluorene compound according to a fourth aspect of the present invention is the fluorene compound according to any one of the first to third aspects of the present invention, wherein the weight of the fluorene compound after heating to 600°C is 26% or more of the weight before heating in thermogravimetric analysis.

[0084] A resin composition according to a fifth aspect of the present invention is a resin composition containing the fluorene compound according to any one of the first to fourth aspects of the present invention and a thermosetting resin.

[0085] A prepreg according to a sixth aspect of the present invention is a prepreg comprising the resin composition according to the fifth aspect of the present invention or a semi-cured product of the resin composition, and a fibrous base material.

[0086] A resin-coated film according to a seventh aspect of the present invention is a resin-coated film comprising a resin layer containing the resin composition according to the fifth aspect of the present invention or a semi-cured product of the resin composition, and a support film.

[0087] The resin-coated metal foil according to the eighth aspect of the present invention is a resin-coated metal foil comprising a resin layer containing the resin composition according to the fifth aspect of the present invention or a semi-cured product of the resin composition, and a metal foil.

[0088] A metal-clad laminate according to a ninth aspect of the present invention is a metal-clad laminate comprising an insulating layer containing a cured product of the resin composition according to the fifth aspect of the present invention and a metal foil.

[0089] A metal-clad laminate according to a tenth aspect of the present invention is a metal-clad laminate comprising an insulating layer containing a cured product of the prepreg according to the sixth aspect of the present invention and a metal foil.

[0090] A wiring board according to an eleventh aspect of the present invention is a wiring board comprising an insulating layer containing a cured product of the resin composition according to the fifth aspect of the present invention, and wiring.

[0091] A wiring board according to a twelfth aspect of the present invention is a wiring board comprising an insulating layer containing a cured product of the prepreg according to the sixth aspect of the present invention, and wiring.

[0092] According to the present invention, a fluorene compound having a low dielectric constant and a low dielectric loss tangent and excellent flame resistance can be provided. Also, according to the present invention, a resin composition containing the fluorene compound, and a prepreg, a resin-coated film, a resin-coated metal foil, a metal-clad laminate, and a wiring board obtained using the resin composition can be provided.

[0093] The present invention will be explained in more detail below with reference to examples, but the scope of the present invention is not limited to these examples.

[0094] [Examples 1 and 2, and Comparative Examples 1 to 3]

[0095] Example 1 The synthesis of a fluorene compound according to Example 1 will be described.

[0096] The fluorene compound represented by the formula (3) was synthesized as shown in the formula (8).

[0097] Specifically, a 200 mL three-neck flask equipped with a water bath, a magnetic stirrer, and a condenser was first prepared. 5.1 g (approximately 12.5 mmol) of the compound represented by formula (A) (2,7-dibromo-9,9-dipropylfluorene, molecular weight: 408), 5.0 g (approximately 37.3 mmol) of the compound represented by formula (B-1) (potassium vinyltrifluoroborate (potassium vinyltrifluoroborate), molecular weight: 134), and 80 mL of tetrahydrofuran (THF) were added to the three-neck flask, and the atmosphere inside the flask was replaced with argon. Tetrakis(triphenylphosphine)palladium(0) [Pd(PPh ３ ) ４ 0.6 g (approximately 0.052 mmol) of potassium carbonate (K) (molecular weight: 1156) was added. Thereafter, the liquid in the three-neck flask was stirred by rotating the stirring bar of the magnetic stirrer. ２ CO ３ 5.16 g (approximately 37.4 mmol) of K (molecular weight: 138) was added to 8 mL of distilled water (product number 043-16785 manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.). ２ CO ３ An aqueous solution (about 4.7 mol / L) was added to the three-necked flask and stirred at reflux temperature (70°C) for 5 hours. This allowed the reaction represented by formula (8) to proceed. The reaction solution obtained by this stirring was cooled to room temperature, and the aqueous phase was removed from the reaction solution. After that, magnesium sulfate (MgSO ４ ) was added to the three-neck flask to dry the oil phase. Then, THF was distilled off. The solid obtained in this way was dissolved in a mixed solvent of toluene and heptane in a volume ratio of 1:1, and fractionation was performed twice using silica gel column chromatography (silica gel: 1.09385.5000 manufactured by Merck) using the mixed solvent (mixed solvent of toluene and heptane) as the elution solvent. The fraction containing the target substance was dried at 70°C using a rotary evaporator. The obtained solid was dried at 70°C and 100 Pa for 1 hour. 2.7 g of a white solid was obtained.

[0098] The purity of the obtained solid was measured using a high performance liquid chromatograph (HPLC) under the following measurement conditions: column: ZORBAX RX-SiL (normal phase) manufactured by Agilent Technologies, Inc., eluent: a mixed solvent of toluene and ethyl acetate in a mass ratio of 1:1, 1.0 / min, observation wavelength: 300 nm. The measurement results (HPLC chart) are shown in FIG. 6. From FIG. 6, it was found that the purity was approximately 99.4%. Note that FIG. 6 shows the HPLC chart during the synthesis of the fluorene compound according to Example 1, with the vertical axis representing intensity (mAU) and the horizontal axis representing elution time (min).

[0099] Then, the obtained solid is １ H-NMR at 400 MHz, solvent: CD ２ Cl ２ The analysis was performed under the measurement conditions of 0.05 mass % trimethylsilane (TMS) content. １ H-NMR spectrum (of the obtained solid １ The H-NMR spectrum is shown in Figure 7. １ From the H-NMR spectrum, it was found that the solid was a fluorene compound represented by the formula (3). １ In the H-NMR spectrum, peak 71 around chemical shift δ7-8 is a peak due to hydrogen of the aromatic ring in the fluorene compound represented by formula (3), peak 72 around chemical shift δ5-7 is a peak due to hydrogen of the vinyl group in the fluorene compound represented by formula (3), and peak 73 around chemical shift δ2 and chemical shift δ0.5-1 are peaks due to hydrogen of the propyl group in the fluorene compound represented by formula (3), so it was confirmed that it was the fluorene compound represented by formula (3). In addition, peak 74 around chemical shift δ1.5 is a peak due to water, and peak 75 around chemical shift δ0 is a peak due to TMS. In addition, Figure 7 shows the fluorene compound according to Example 1. １ 1 H-NMR spectrum is shown, where the vertical axis indicates intensity and the horizontal axis indicates chemical shift δ.

[0100] The molecular weight of the fluorene compound represented by the formula (3) was 302, and the purity was about 99.4%, so the yield of the fluorene compound represented by the formula (3) in this reaction was about 71%.

[0101] Example 2 The synthesis of a fluorene compound according to Example 2 will be described.

[0102] The fluorene compound represented by the formula (4) was synthesized as shown in the formula (9).

[0103] Specifically, a 200 mL three-neck flask equipped with a water bath, a magnetic stirrer, and a condenser was first prepared. 4.6 g (approximately 11.3 mmol) of the compound represented by formula (A) (2,7-dibromo-9,9-dipropylfluorene, molecular weight: 408), 5.0 g (approximately 33.8 mmol) of the compound represented by formula (B-2) (4-vinylphenylboronic acid, molecular weight: 148), and 80 mL of tetrahydrofuran (THF) were added to the three-neck flask, and the atmosphere inside the flask was replaced with argon. Tetrakis(triphenylphosphine)palladium(0) [Pd(PPh ３ ) ４ 0.6 g (approximately 0.052 mmol) of potassium carbonate (K) (molecular weight: 1156) was added. Thereafter, the liquid in the three-neck flask was stirred by rotating the stirring bar of the magnetic stirrer. ２ CO ３ 4.67 g (approximately 33.8 mmol) of K (molecular weight: 138) was added to 16 mL of distilled water (product number 043-16785 manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.). ２ CO ３ An aqueous solution (approximately 2.1 mol / L) was added to the three-neck flask and stirred at reflux temperature (70°C) for 5 hours. This allowed the reaction represented by formula (9) to proceed. The reaction solution obtained by this stirring was cooled to room temperature, and the aqueous phase was removed from the reaction solution. After that, magnesium sulfate (MgSO ４) was poured into the three-neck flask to dry the oil phase. Then, THF was distilled off. The solid obtained in this manner was dissolved in toluene at 70°C, and fractionation was performed twice using silica gel column chromatography (silica gel: 1.09385.5000 manufactured by Merck) using toluene as the elution solvent. The fraction containing the target substance was dried at 70°C using a rotary evaporator. The obtained solid was suspended and washed once with 50 mL of ethanol and once with 50 mL of heptane. The suspended and washed solid was then dissolved in as little toluene at 70°C as possible, and reprecipitated by gradually adding heptane. The solid obtained by this reprecipitation was dissolved in as little toluene at 70°C as possible, and reprecipitated by gradually adding heptane. That is, reprecipitation was performed twice. The solid obtained by this reprecipitation twice was dried at 70°C and 100 Pa for 1 hour. 1.69 g of a white solid was obtained.

[0104] The purity of the obtained solid was measured using a high performance liquid chromatograph (HPLC) under the following measurement conditions: column: ZORBAX RX-SiL (normal phase) manufactured by Agilent Technologies, Inc., eluent: a mixed solvent of toluene and ethyl acetate in a mass ratio of 1:1, 1.0 / min, observation wavelength: 300 nm. The measurement results (HPLC chart) are shown in Figure 8. From Figure 8, it was found that the purity was approximately 99.6%. Note that Figure 8 shows the HPLC chart during the synthesis of the fluorene compound of Example 2, with the vertical axis representing intensity (mAU) and the horizontal axis representing elution time (min).

[0105] Then, the obtained solid is １ H-NMR at 400 MHz, solvent: CD ２ Cl ２ The analysis was performed under the measurement conditions of 0.05% by mass of TMS. １ H-NMR spectrum (of the obtained solid １ The H-NMR spectrum is shown in Figure 9. １ From the H-NMR spectrum, it was found that the solid was a fluorene compound represented by the formula (4).１ In the H-NMR spectrum, peak 91 near chemical shift δ7-8 is a peak due to hydrogen atoms of the aromatic ring in the fluorene compound represented by formula (4), peak 92 near chemical shift δ5-7 is a peak due to hydrogen atoms of the vinyl group in the fluorene compound represented by formula (4), and peaks 93 near chemical shift δ2 and chemical shift δ0.5-1 are peaks due to hydrogen atoms of the propyl group in the fluorene compound represented by formula (4), confirming that the fluorene compound is represented by formula (4). Peak 94 near chemical shift δ1.5 is a peak due to water, and peak 95 near chemical shift δ0 is a peak due to TMS. FIG. 9 shows the structure of the fluorene compound according to Example 2. １ 1 H-NMR spectrum is shown, where the vertical axis indicates intensity and the horizontal axis indicates chemical shift δ.

[0106] The molecular weight of the fluorene compound represented by the formula (4) was 455, and the purity was about 99.6%, so the yield of this reaction was about 33%.

[0107] Comparative Example 1 The compound according to Comparative Example 1 is a compound represented by the following formula (10) (4,4'-divinylbiphenyl (DVBP), DVBP manufactured by JFE Chemical Corporation).

[0108]

[0109] Comparative Example 2 The compound according to Comparative Example 2 is a compound (fluorene) represented by the following formula (11).

[0110]

[0111] Comparative Example 3 The compound according to Comparative Example 3 is a compound represented by the following formula (12) (9,9-bis(4-allyloxyphenyl)fluorene).

[0112]

[0113] [Evaluation] The compounds according to Examples 1 and 2 and Comparative Examples 1 to 3 were evaluated as follows.

[0114] (Flame Resistance) Using a thermogravimetric-differential thermal analyzer (TG-DTA) device (STA300 manufactured by Hitachi High-Tech Science Corporation), the residual mass ratio (the ratio of the weight of the residue when heated to 600°C to the mass before heating) of each compound according to Example 1, Example 2, and Comparative Examples 1 to 3 was measured when heated to 600°C. The higher this residual mass ratio, the higher the flame resistance; for example, a residual mass ratio of 26% by mass or more indicates sufficient flame resistance.

[0115] (Dielectric Properties: Dielectric Loss Tangent) The dielectric loss tangent at 1 GHz of each of the compounds according to Example 1, Example 2, and Comparative Examples 1 to 3 was measured by a cavity resonator perturbation method. Specifically, the dielectric loss tangent (Df) of each compound at 1 GHz was measured using a network analyzer (N5230A manufactured by Keysight Technologies, Inc.). If the measured dielectric loss tangent Df was 0.00001 to 0.001, it was determined to be "passed."

[0116] The results are shown in Table 1.

[0117]

[0118] As can be seen from Table 1, the fluorene compound represented by formula (1) (specifically, the fluorene compound according to Example 1: the fluorene compound represented by formula (3), and the fluorene compound according to Example 2: the fluorene compound represented by formula (4)) had a higher residual mass percentage than the compound according to Comparative Example 2 (the compound represented by formula (11)) and the compound according to Comparative Example 3 (the compound represented by formula (12)), specifically, a high residual mass percentage of 30 mass% or more. Furthermore, the fluorene compound represented by formula (1) had a lower dielectric loss tangent than the compound according to Comparative Example 1 (the compound represented by formula (10)) and the compound according to Comparative Example 3 (the compound represented by formula (12)), specifically, a low dielectric loss tangent of 0.00001 to 0.001. Therefore, it was found that the fluorene compound represented by formula (1) is a fluorene compound having a low relative dielectric constant and dielectric loss tangent and excellent flame resistance.

[0119] When the fluorene compounds according to Examples 1 and 2 were incorporated into a resin, a resin composition was obtained that had a low relative dielectric constant and dielectric loss tangent and excellent flame resistance, regardless of the type of resin incorporated, compared to when the fluorene compounds according to Comparative Examples 1 to 3 were incorporated into the same resin at the same content.

[0120] When the prepregs obtained using the resin compositions containing the fluorene compounds according to Examples 1 and 2 were cured, the cured products had lower relative dielectric constants and dielectric loss tangents and were superior in flame resistance compared to the cured products of the prepregs obtained using the fluorene compounds according to Comparative Examples 1 to 3.

[0121] By curing the resin layer containing the resin composition containing the fluorene compound according to Example 1 and Example 2, an insulating layer having a lower dielectric constant and dielectric dissipation factor and superior flame resistance was obtained compared to the insulating layer obtained by curing the resin layer containing the fluorene compound according to Comparative Examples 1 to 3. Therefore, by using the resin composition containing the fluorene compound according to Example 1 and Example 2, it was possible to produce a resin-coated metal foil and a resin-coated film having a resin layer that, upon curing, becomes an insulating layer having a low dielectric constant and dielectric dissipation factor and superior flame resistance. Furthermore, by using the resin composition containing the fluorene compound according to Example 1 and Example 2, a metal-clad laminate and a wiring board having an insulating layer having a low dielectric constant and dielectric dissipation factor and superior flame resistance were obtained.

[0122] This application is based on Japanese Patent Application No. 2024-051827 filed on March 27, 2024, the contents of which are incorporated herein by reference.

[0123] In order to express the present invention, the present invention has been properly and sufficiently described through the embodiments in the above, but it should be recognized that those skilled in the art can easily change and / or improve the above-mentioned embodiments. Therefore, unless the changes or improvements made by those skilled in the art are at a level that causes departure from the scope of the claims described in the claims, such changes or improvements are interpreted as being included in the scope of the claims.

[0124] The present invention provides a fluorene compound having a low dielectric constant and dielectric loss tangent and excellent flame resistance. The present invention also provides a resin composition containing the fluorene compound, and a prepreg, a resin-coated film, a resin-coated metal foil, a metal-clad laminate, and a wiring board obtained using the resin composition.

Claims

1. A fluorene compound represented by the following formula (1): [In formula (1), R １ and R ２ each independently represents an alkyl group having 2 to 5 carbon atoms; R ３ and R ４ each independently represents at least one of an alkenyl group and a group represented by the following formula (2): [In formula (2), p represents 0 to 10, and R ５ ~R ７ each independently represents a hydrogen atom or an alkyl group, and Ar represents an arylene group.

2. The fluorene compound according to claim 1, wherein the fluorene compound represented by formula (1) includes at least one of a fluorene compound represented by the following formula (3) and a fluorene compound represented by the following formula (4):

3. The fluorene compound according to claim 1, which has a dielectric loss tangent of 0.00001 to 0.001 at a frequency of 1 GHz.

4. The fluorene compound according to claim 1, wherein the weight after heating to 600°C is 26% or more of the weight before heating in thermogravimetric analysis.

5. A resin composition comprising the fluorene compound according to any one of claims 1 to 4 and a thermosetting resin.

6. A prepreg comprising the resin composition according to claim 5 or a semi-cured product of said resin composition and a fibrous base material.

7. A resin-coated film comprising a resin layer containing the resin composition according to claim 5 or a semi-cured product of said resin composition, and a support film.

8. A resin-coated metal foil comprising a resin layer containing the resin composition according to claim 5 or a semi-cured product of said resin composition, and a metal foil.

9. A metal-clad laminate comprising an insulating layer containing a cured product of the resin composition according to claim 5 and a metal foil.

10. A metal-clad laminate comprising an insulating layer containing the cured product of the prepreg according to claim 6 and a metal foil.

11. A wiring board comprising an insulating layer containing a cured product of the resin composition according to claim 5 and wiring.

12. A wiring board comprising an insulating layer containing the cured product of the prepreg according to claim 6 and wiring.

Images