Resin composition, and prepregs, resin-coated films, resin-coated metal foils, metal-clad laminates, and wiring boards using the same.

Abstract

One aspect of the present invention relates to a resin composition containing a maleimide compound (A) having an indane structure in each molecule, and a hydrocarbon compound (B) represented by formula (1). [In formula (1), X represents a C6 or higher hydrocarbon group that includes at least one selected from aromatic ring groups and aliphatic ring groups. n represents an integer of 1-10.]

Description

Technical Field

[0001] The present invention relates to a resin composition, a prepreg using the same, a resin film, a metal foil with resin, a metal-clad laminate, and a wiring board.

Background Art

[0002] In recent years, with the increase in the amount of information processing in various electronic devices, mounting technologies such as high integration of semiconductor devices, high density of wirings, and multi-layerization have been rapidly advancing. For the substrate material constituting the base material of the wiring board used in various electronic devices, it is required to have a low dielectric constant and a low dielectric tangent in order to increase the signal transmission speed and reduce the loss during signal transmission.

[0003] Particularly, as represented by a substrate-like printed wiring board (SLP), in recent years, the boundary between the printed wiring board and the semiconductor package substrate has been disappearing. Therefore, with the miniaturization and high performance of recent electronic devices and the remarkable improvement in information communication speed, it has been required for any substrate to have high-frequency compatibility, excellent heat resistance, and low thermal expansion.

[0004] As a material for such a substrate, maleimide resin is used in that high heat resistance can be ensured, and maleimide having a low dielectric constant and a low dielectric tangent has been proposed in order to achieve low transmission loss in high-frequency applications.

[0005] For example, in Patent Document 1, a resin composition having cured product characteristics with a balanced high glass transition temperature (Tg) and dielectric characteristics (relative dielectric constant, dielectric tangent), etc., is disclosed by combining a polymaleimide resin having a specific structure and a compound containing an unsaturated double bond group.

[0006] Further, in Patent Document 2, a curable resin composition has been reported which, by containing a maleimide having an indane skeleton and a diene polymer, can have a cured product having a low dielectric constant, a low dielectric tangent, and excellent high Tg.

[0007] However, while a certain degree of low dielectric properties can be obtained by using maleimide resins described in Patent Documents 1 and 2, there is a need to ensure even lower dielectric properties. Furthermore, maleimide resins have the drawback of high water absorption, and ensuring low water absorption has not yet been achieved. Wiring boards used in various electronic devices are also required to be less susceptible to changes in the external environment. For example, in order to enable the use of wiring boards even in high-humidity environments, the substrate material that constitutes the insulating layer of the wiring board is required to produce a cured product with low water absorption. It is thought that the insulating layer of a wiring board obtained from a substrate material that produces such a cured product with low water absorption can suppress moisture absorption.

[0008] The present invention has been made in view of these circumstances, and aims to provide a resin composition that can achieve even lower dielectric properties and lower water absorption in the cured product while maintaining properties such as high Tg. The present invention also aims to provide a prepreg, a resin-coated film, a resin-coated metal foil, a metal-clad laminate, and a wiring board using the resin composition. [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] Japanese Patent Publication No. 2017-137492 [Patent Document 2] International Publication No. 2020 / 217678 [Overview of the Initiative]

[0010] A resin composition according to one aspect of the present invention is characterized by containing a maleimide compound (A) having an indan structure in its molecule and a hydrocarbon compound (B) represented by the following formula (1).

[0011] [ka] [In formula (1), X represents a hydrocarbon group having 6 or more carbon atoms, comprising at least one selected from aromatic cyclic groups and aliphatic cyclic groups. n represents an integer from 1 to 10.] [Brief explanation of the drawing]

[0012] [Figure 1] Figure 1 is a schematic cross-sectional view showing the configuration of a prepreg according to one embodiment of the present invention. [Figure 2] Figure 2 is a schematic cross-sectional view showing the configuration of a metal-clad laminate according to one embodiment of the present invention. [Figure 3] Figure 3 is a schematic cross-sectional view showing the configuration of a wiring board according to one embodiment of the present invention. [Figure 4] Figure 4 is a schematic cross-sectional view showing the structure of a resin-coated metal foil according to one embodiment of the present invention. [Figure 5] Figure 5 is a schematic cross-sectional view showing the structure of a resin-coated film according to one embodiment of the present invention. [Figure 6] Figure 6 shows the GPC chart of the compound obtained in Synthesis Example 1. [Figure 7] Figure 7 shows the 1H-NMR chart of the compound obtained in Synthesis Example 1. [Figure 8] Figure 8 shows the GPC chart of the compound obtained in Synthesis Example 2. [Figure 9] Figure 9 shows the 1H-NMR chart of the compound obtained in Synthesis Example 2. [Modes for carrying out the invention]

[0013] A resin composition according to an embodiment of the present invention (hereinafter also simply referred to as a resin composition) is characterized by comprising a maleimide compound (A) having an indane structure in its molecule and a hydrocarbon compound (B) represented by formula (1).

[0014] By including the hydrocarbon compound (B) in addition to the maleimide compound (A) having an indane structure in its molecule, it is possible to achieve even lower dielectric properties and lower water absorption in the cured product while maintaining a high Tg (glass transition temperature).

[0015] Also, as a material property, in a material with a high Tg of the cured product, heat resistance (such as solder heat resistance and reflow heat resistance) is one of the factors for further improvement. Also, the fact that the cured product is a material with a high Tg has the advantage that the thermal expansion coefficient of the material in the temperature range from room temperature to reflow or solder temperature is a small value. This is because generally, at a temperature exceeding the glass transition temperature, the thermal expansion rapidly becomes large. That is, if the glass transition temperature is low, in the high-temperature region exceeding the glass transition temperature, the thermal expansion coefficient becomes large. If the glass transition temperature is low, the thermal expansion in a higher temperature region becomes large, and in a wiring board, for example, problems such as warping may occur, and there is a risk of a decrease in connection reliability.

[0016] Therefore, according to the present embodiment, it is possible to obtain further low dielectric characteristics and low water absorption in the cured product while maintaining characteristics such as low dielectric characteristics and high Tg, and to provide a resin composition. Further, by using the resin composition, it is possible to provide a prepreg, a film with resin, a metal foil with resin, a metal-clad laminate, and a wiring board having characteristics such as low dielectric characteristics, low water absorption, and high Tg.

[0017] Hereinafter, each component of the resin composition according to the present embodiment will be specifically described.

[0018] <Maleimide compound (A)> The maleimide compound (A) used in the present embodiment is not particularly limited as long as it is a maleimide compound having an indane structure in the molecule. By using such a maleimide compound, a resin composition having both high Tg and low dielectric characteristics can be obtained.

[0019] Examples of the indan structure include a divalent group formed by removing two hydrogen atoms from indan or an indan substituted with a substituent, and more specifically, a structure represented by the following formula (2). In other words, an example of the maleimide compound (A) is a maleimide compound having the structure represented by the following formula (2) in its molecule. The maleimide compound (A) also has a maleimide group in its molecule.

[0020] [ka]

[0021] In formula (2), each Rb is independent. That is, each Rb may be the same group or a different group. For example, if r is 2 or 3, the two or three Rb groups bonded to the same benzene ring may be the same group or a different group. Rb represents an alkyl group having 1 to 10 carbon atoms, an alkyloxy group (alkoxy group) having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an arylthio group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a hydroxyl group, or a mercapto group (thiol group). Also, r represents an integer from 0 to 3.

[0022] More specifically, examples include maleimide compounds (A1) having a structure represented by the following formula (3) in their molecule.

[0023] [ka]

[0024] In formula (3), each Ra is independent. That is, each Ra may be the same group or a different group. For example, when q is 2 to 4, the 2 to 4 Ra groups bonded to the same benzene ring may be the same group or a different group. Ra represents an alkyl group having 1 to 10 carbon atoms, an alkyloxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an arylthio group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a nitro group, a hydroxyl group, or a mercapto group. Rb is the same as Rb in formula (1), and each independently represents a C1-C10 alkyl group, a C1-C10 alkyloxy group, a C1-C10 alkylthio group, a C6-C10 aryl group, a C6-C10 aryloxy group, a C6-C10 arylthio group, a C3-C10 cycloalkyl group, a halogen atom, a nitro group, a hydroxyl group, or a mercapto group. q is an integer from 0 to 4. r is an integer from 0 to 3. n is an integer from 0.95 to 10.

[0025] r is the average value of the degree of substitution of Rb, and a smaller value is preferable, specifically, a value of 0 is preferable. That is, in the benzene ring to which Rb can be bonded, it is preferable that a hydrogen atom is bonded at the position where Rb can be bonded. The maleimide compound with r = 0 has the advantage of being easy to synthesize. This is thought to be due to reduced steric hindrance and increased electron density of the aromatic ring. Furthermore, when r is 1 to 3, Rb is preferably at least one selected from the group consisting of C1-C4 alkyl groups, C3-C6 cycloalkyl groups, and C6-C10 aryl groups among the groups mentioned above. Furthermore, Ra is preferably at least one selected from the group consisting of C1-C4 alkyl groups, C3-C6 cycloalkyl groups, and C6-C10 aryl groups among the groups mentioned above. It is thought that by using C1-C4 alkyl groups, C3-C6 cycloalkyl groups, and C6-C10 aryl groups, the compound becomes more soluble in solvents, and the decrease in the reactivity of the maleimide group can be suppressed, resulting in a suitable cured product. This is thought to be due to a decrease in planarity and crystallinity near the maleimide group.

[0026] The following are specific examples of groups represented by Ra and Rb.

[0027] The C1-C10 alkyl group is not particularly limited, and examples include methyl, ethyl, propyl, hexyl, and decyl groups.

[0028] The alkyloxy group having 1 to 10 carbon atoms is not particularly limited, and examples include methyloxy group, ethyloxy group, propyloxy group, hexyloxy group, and decyloxy group.

[0029] The alkylthio group having 1 to 10 carbon atoms is not particularly limited, and examples include methylthio group, ethylthio group, propylthio group, hexylthio group, and decylthio group.

[0030] The aryl group having 6 to 10 carbon atoms is not particularly limited, and examples include a phenyl group and a naphthyl group.

[0031] The aryloxy group having 6 to 10 carbon atoms is not particularly limited, and examples include a phenyloxy group and a naphthyloxy group.

[0032] The arylthio group having 6 to 10 carbon atoms is not particularly limited, and examples include a phenylthio group and a naphthylthio group.

[0033] The cycloalkyl group having 3 to 10 carbon atoms is not particularly limited, and examples include a cyclopropyl group, a cyclobutyl group, a cyclohexyl group, and a cyclooctyl group.

[0034] Examples of the halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms.

[0035] q is the average degree of substitution of Ra, preferably 2 to 3, and more preferably 2. Maleimide compounds with q = 2 have the advantage of being easy to synthesize. This is thought to be because, especially when q is 2, the steric hindrance decreases and the electron density of the aromatic ring increases.

[0036] n is the average value of the number of repetitions, and as described above, it is preferably 0.95 to 10, more preferably 0.98 to 8, more preferably 1 to 7, and even more preferably 1.1 to 6. Furthermore, in the maleimide compound (A1) represented by formula (3), it is preferable that the content of the maleimide compound in which n, the average value of the number of repetitions (degree of polymerization), is 0 is 32% by mass or less of the total amount of the maleimide compound.

[0037] The maleimide compound (A) of this embodiment preferably has a molecular weight distribution (Mw / Mn) of 1 to 4, more preferably 1.1 to 3.8, even more preferably 1.2 to 3.6, and particularly preferably 1.3 to 3.4, obtained by GPC measurement. The molecular weight distribution is obtained by GPC measurement.

[0038] More specifically, the maleimide compound (A) can be, for example, maleimide compounds represented by the following formulas (5) to (7).

[0039] [ka]

[0040] In equation (5), n represents an integer between 0.95 and 10.

[0041] [ka]

[0042] In equation (6), n represents an integer between 0.95 and 10.

[0043] [ka]

[0044] In equation (7), n represents an integer between 0.95 and 10.

[0045] The method for producing the maleimide compound (A) of this embodiment is not particularly limited. Specifically, for example, it can be obtained by a so-called maleimide reaction, in which an amine compound represented by the following formula (8) and maleic anhydride are reacted in an organic solvent such as toluene in the presence of a catalyst such as toluenesulfonic acid. More specifically, after this maleimide reaction, unreacted maleic anhydride and other impurities are removed by washing with water or the like, and the solvent is removed by reducing the pressure. A dehydrating agent may be used during this reaction.

[0046] [ka]

[0047] In formula (8), each Ra is independent. That is, each Ra may be the same group or a different group. For example, when q is 2 to 4, the 2 to 4 Ra groups bonded to the same benzene ring may be the same group or a different group. Ra represents an alkyl group having 1 to 10 carbon atoms, an alkyloxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an arylthio group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a nitro group, a hydroxyl group, or a mercapto group. Rb is the same as Rb in formula (1), and each independently represents a C1-C10 alkyl group, a C1-C10 alkyloxy group, a C1-C10 alkylthio group, a C6-C10 aryl group, a C6-C10 aryloxy group, a C6-C10 arylthio group, a C3-C10 cycloalkyl group, a halogen atom, a nitro group, a hydroxyl group, or a mercapto group. q is an integer from 0 to 4. r is an integer from 0 to 3. n is an integer from 0.95 to 10.

[0048] The amine compound represented by formula (8) can be obtained, for example, by reacting 2,6-dimethylaniline and α,α'-dihydroxy-1,3-diisopropylbenzene in an organic solvent such as xylene, using activated clay as a catalyst.

[0049] In this embodiment, a commercially available maleimide compound (A) can also be used.

[0050] <Hydrogen compounds (B)> The hydrocarbon compound (B) contained in the resin composition of this embodiment is a compound represented by the following formula (1).

[0051] [ka]

[0052] In formula (1), X represents a hydrocarbon group having 6 or more carbon atoms, which includes at least one selected from aromatic cyclic groups and aliphatic cyclic groups. Also, n represents an integer from 1 to 10.

[0053] By including such hydrocarbon compound (B), the resin composition of this embodiment is expected to achieve even lower dielectric properties in its cured product while maintaining a high Tg, and furthermore, to suppress water absorption to a low level.

[0054] The aforementioned aromatic cyclic group is not particularly limited, but examples include a phenylene group, a xylylene group, a naphthylene group, a torylene group, a biphenylene group, and the like.

[0055] The aliphatic cyclic group is not particularly limited, but examples include a group containing an indane structure represented by formula (2), a group containing a cycloolefin structure, and the like.

[0056] The number of carbon atoms is not particularly limited as long as it is 6 or more, but from the viewpoint of maintaining a high Tg, it is more preferably 6 or more and 20 or less.

[0057] In a preferred embodiment, the hydrocarbon compound of this embodiment includes a hydrocarbon compound (B1) represented by the following formula (4).

[0058] [ka]

[0059] In equation (4), n represents an integer between 1 and 10.

[0060] It is believed that including such a hydrocarbon compound (B1) makes it possible to more reliably obtain the effects described above.

[0061] <Reactive compound (C)> The resin composition according to this embodiment may optionally contain a reactive compound (C) that reacts with at least one of the maleimide compound (A) and the hydrocarbon compound (B), to the extent that it does not impair the effects of the present invention. It is believed that by including such a reactive compound (C), adhesion (e.g., adhesion to metal foil) and low thermal expansion can be further imparted to the resin composition.

[0062] Here, a reactive compound refers to a compound that reacts with at least one of the hydrocarbon compound (B) and the maleimide compound to contribute to the curing of the resin composition. Examples of the reactive compound (C) include a maleimide compound (D) different from the maleimide compound (A), epoxy compounds, methacrylate compounds, acrylate compounds, vinyl compounds, cyanate ester compounds, activated ester compounds, allyl compounds, benzoxazine compounds, phenol compounds, and polyphenylene ether compounds.

[0063] Maleimide compound (D), which is different from maleimide compound (A), is a maleimide compound that has a maleimide group in its molecule and does not have an indane structure in its molecule. Maleimide compound (D) is not particularly limited as long as it has one or more maleimide groups in its molecule and does not have an indane structure in its molecule, but examples include maleimide compounds having one or more maleimide groups in their molecule and modified maleimide compounds.

[0064] More specific examples of the maleimide compound (D) include phenyl maleimide compounds such as 4,4'-diphenylmethanebismaleimide, polyphenylmethanemaleimide, m-phenylenebismaleimide, bisphenol A diphenyl etherbismaleimide, 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethanebismaleimide, 4-methyl-1,3-phenylenebismaleimide, biphenylaralkyl type polymaleimide compounds, and N-alkylbismaleimide compounds having an aliphatic skeleton. Examples of the modified maleimide compound include modified maleimide compounds in which part of the molecule is modified with an amine compound, and modified maleimide compounds in which part of the molecule is modified with a silicone compound. As a maleimide compound different from the aforementioned maleimide compound, commercially available products may be used. For example, MIR-3000-70MT and MIR-5000 from Nippon Kayaku Co., Ltd., BMI-4000, BMI-5100, BMI-2300, and BMI-TMH from Yamato Kasei Kogyo Co., Ltd., and BMI-689, BMI-1500, BMI-3000J, and BMI-5000 from Designer Molecules Inc. may be used.

[0065] The epoxy compounds are compounds having an epoxy group in their molecule, and specifically include bixylenol-type epoxy compounds, bisphenol A-type epoxy compounds, bisphenol F-type epoxy compounds, bisphenol S-type epoxy compounds, bisphenol AF-type epoxy compounds, dicyclopentadiene-type epoxy compounds, trisphenol-type epoxy compounds, naphthol novolac-type epoxy compounds, phenol novolac-type epoxy compounds, tert-butyl-catechol-type epoxy compounds, naphthalene-type epoxy compounds, naphthol-type epoxy compounds, anthracene-type epoxy compounds, glycidylamine-type epoxy compounds, glycidyl ester-type epoxy compounds, cresol novolac-type epoxy compounds, biphenyl-type epoxy compounds, linear aliphatic epoxy compounds, epoxy compounds having a butadiene structure, alicyclic epoxy compounds, heterocyclic epoxy compounds, spiro-ring-containing epoxy compounds, cyclohexane-type epoxy compounds, cyclohexanedimethanol-type epoxy compounds, naphthylene ether-type epoxy compounds, trimethylol-type epoxy compounds, and tetraphenylethane-type epoxy compounds. Furthermore, the epoxy compound also includes epoxy resins, which are polymers of each of the epoxy compounds.

[0066] The methacrylate compound is a compound having a methacryloyl group in its molecule, and examples include monofunctional methacrylate compounds having one methacryloyl group in their molecule, and polyfunctional methacrylate compounds having two or more methacryloyl groups in their molecule. Examples of the monofunctional methacrylate compound include methyl methacrylate, ethyl methacrylate, propyl methacrylate, and butyl methacrylate. Examples of the polyfunctional methacrylate compound include dimethacrylate compounds such as tricyclodecanedimethanol dimethacrylate (DCP).

[0067] The acrylate compound is a compound having an acryloyl group in its molecule, and examples include monofunctional acrylate compounds having one acryloyl group in their molecule, and polyfunctional acrylate compounds having two or more acryloyl groups in their molecule. Examples of the monofunctional acrylate compound include methyl acrylate, ethyl acrylate, propyl acrylate, and butyl acrylate. Examples of the polyfunctional acrylate compound include diacrylate compounds such as tricyclodecanedimethanol diacrylate.

[0068] The vinyl compound is a compound having a vinyl group in its molecule, and examples include monofunctional vinyl compounds (monovinyl compounds) having one vinyl group in their molecule, and polyfunctional vinyl compounds having two or more vinyl groups in their molecule. Examples of the polyfunctional vinyl compound include divinylbenzene, curable polybutadiene having a carbon-carbon unsaturated double bond in its molecule, and curable butadiene-styrene copolymer having a carbon-carbon unsaturated double bond in its molecule.

[0069] The aforementioned cyanate ester compounds are compounds having a cyanate group in their molecule, and examples include phenol novolac type cyanate ester compounds, naphthol aralkyl type cyanate ester compounds, biphenyl aralkyl type cyanate ester compounds, naphthylene ether type cyanate ester compounds, xylene resin type cyanate ester compounds, adamantane skeleton type cyanate ester compounds, and the like.

[0070] The aforementioned active ester compounds are compounds having highly reactive ester groups in their molecules, and examples include benzenecarboxylic acid active esters, benzenedicarboxylic acid active esters, benzenetricarboxylic acid active esters, benzenetetracarboxylic acid active esters, naphthalenecarboxylic acid active esters, naphthalenedicarboxylic acid active esters, naphthalentricarboxylic acid active esters, naphthalenetetracarboxylic acid active esters, fluorenecarboxylic acid active esters, fluorentricarboxylic acid active esters, and fluorenetetracarboxylic acid active esters.

[0071] The allyl compounds are compounds having an allyl group in their molecule, and examples include triallyl isocyanurate compounds such as triallyl isocyanurate (TAIC), diallyl bisphenol compounds, and diallyl phthalate (DAP).

[0072] The benzoxazine compound can be, for example, a benzoxazine compound represented by the following general formula (CI).

[0073] [ka]

[0074] In formula (C-1), R 1 represents the k-valence base, R 2 Each of these independently represents a halogen atom, an alkyl group, or an aryl group. k represents an integer from 2 to 4, and l represents an integer from 0 to 4.

[0075] Commercially available products include "JBZ-OP100D" and "ODA-BOZ" from JFE Chemical Corporation; "Pd," "Fa," and "ALP-d" from Shikoku Chemicals Corporation; and "HFB2006M" from Showa Polymer Co., Ltd.

[0076] The phenol compounds can include compounds containing a hydroxyl group bonded to an aromatic ring in their molecule. Examples include bisphenol A type phenol compounds, bisphenol E type phenol compounds, bisphenol F type phenol compounds, bisphenol S type phenol compounds, phenol novolac compounds, bisphenol A novolac type phenol compounds, glycidyl ester type phenol compounds, aralkyl novolac type phenol compounds, biphenyl aralkyl type phenol compounds, cresol novolac type phenol compounds, polyfunctional phenol compounds, naphthol compounds, naphthol novolac compounds, polyfunctional naphthol compounds, anthracene type phenol compounds, naphthalene skeleton-modified novolac type phenol compounds, phenol aralkyl type phenol compounds, naphthol aralkyl type phenol compounds, dicyclopentadiene type phenol compounds, biphenyl type phenol compounds, alicyclic phenol compounds, polyol type phenol resins, phosphorus-containing phenol compounds, polymerizable unsaturated hydrocarbon group-containing phenol compounds, and hydroxyl group-containing silicone compounds.

[0077] The aforementioned polyphenylene ether compounds can be synthesized by known methods or commercially available compounds can be used. Examples of commercially available compounds include "OPE-2st 1200" and "OPE-2st 2200" from Mitsubishi Gas Chemical Company, Inc., and "SA9000," "SA90," "SA120," and "Noryl640" from SABIC Innovative Plastics Corporation.

[0078] The reactive compound (C) may be any of the compounds listed above, either individually or in combination of two or more.

[0079] (Content) In the resin composition of this embodiment, the content of the maleimide compound (A) is preferably 20 to 80 parts by mass per 100 parts by mass of the total mass of the maleimide compound (A) and the hydrocarbon compound (B). Within this range, it is considered that the effects of the present invention described above can be obtained more reliably. The more preferable range is 30 parts by mass or more and 70 parts by mass or less.

[0080] Furthermore, if the resin composition of this embodiment contains the reactive compound (C), the content of the hydrocarbon compound (B) is preferably 5 to 50 parts by mass, and more preferably 20 to 50 parts by mass, based on 100 parts by mass of the total of the maleimide compound (A), the hydrocarbon compound (B), and the reactive compound (C).

[0081] In that case, the content of the reactive compound (C) is preferably 1 to 40 parts by mass, and more preferably 1 to 30 parts by mass, based on 100 parts by mass of the total of the maleimide compound (A), the hydrocarbon compound (B), and the reactive compound (C).

[0082] (Inorganic fillers) The resin composition according to this embodiment may further contain an inorganic filler. Examples of inorganic fillers include those added to enhance the heat resistance and flame retardancy of the cured resin composition, and are not particularly limited. It is believed that by including an inorganic filler, it is possible to further enhance the heat resistance and flame retardancy, as well as suppress the coefficient of thermal expansion to a lower level (achieving even lower thermal expansion).

[0083] Specific examples of inorganic fillers that can be used in this embodiment include, for example, silica, alumina, titanium oxide, magnesium oxide and mica, metal oxides such as magnesium hydroxide and aluminum hydroxide, talc, aluminum borate, barium sulfate, aluminum nitride, boron nitride, barium titanate, strontium titanate, calcium titanate, aluminum titanate, barium zirconate titanate, barium zirconate, calcium zirconate, zirconium phosphate, and magnesium carbonate such as zirconium tungstate phosphate and anhydrous magnesium carbonate, and calcium carbonate, as well as boehmite-treated versions thereof. Among these, silica, metal hydroxides such as magnesium hydroxide and aluminum hydroxide, aluminum oxide, boron nitride, and barium titanate and strontium titanate are preferred, with silica being more preferred. The silica is not particularly limited and examples include crushed silica, spherical silica, and silica particles.

[0084] These inorganic fillers may be used individually or in combination of two or more types. Furthermore, while the inorganic fillers described above may be used as is, they may also be surface-treated with epoxysilane, vinylsilane, methacrylicsilane, phenylaminosilane, or aminosilane type silane coupling agents. These silane coupling agents can be added using an integral blending method, rather than being pre-surface-treated with the fillers.

[0085] If the resin composition of this embodiment contains an inorganic filler, its content is preferably 10 to 300 parts by mass, and more preferably 40 to 250 parts by mass, based on 100 parts by mass of the total mass of the maleimide compound (A) and the hydrocarbon compound (B).

[0086] (Flame retardant) The resin composition according to this embodiment may further contain a flame retardant. By including a flame retardant, the flame retardancy of the cured product of the resin composition can be further enhanced.

[0087] The flame retardants that can be used in this embodiment are not particularly limited. Specifically, in fields where halogen-based flame retardants such as brominated flame retardants are used, for example, ethylenedipentabromobenzene, ethylenebistetrabromoimide, decabromodiphenyl oxide, and tetradecabromodifenoxybenzene, which have a melting point of 300°C or higher, are preferred. It is believed that by using halogen-based flame retardants, the desorption of halogens at high temperatures can be suppressed, thereby suppressing the decrease in heat resistance. In addition, in fields where halogen-free is required, flame retardants containing phosphorus (phosphorus-based flame retardants) may be used. The phosphorus-based flame retardants are not particularly limited, but examples include HCA-based flame retardants, phosphate ester-based flame retardants, phosphazene-based flame retardants, bisdiphenylphosphine oxide-based flame retardants, and phosphinate-based flame retardants. Specific examples of HCA-based flame retardants include 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-yl-10-oxide, 10-(2,5-dihydroxyphenyl)-9,10-dihydro9-oxa-10-phosphaphenanthrene-10-oxide, or compounds obtained by pre-reacting these. Specific examples of phosphate ester-based flame retardants include condensed phosphate esters of dixylenyl phosphate. Specific examples of phosphazene-based flame retardants include phenoxyphosphazene. Specific examples of bis-diphenylphosphine oxide-based flame retardants include xylylenebis-diphenylphosphine oxide. Specific examples of phosphinate-based flame retardants include, for example, phosphinate metal salts of aluminum dialkylphosphinate salts. The flame retardants described above may be used individually or in combination of two or more.

[0088] If the resin composition of this embodiment contains a flame retardant, its content is preferably 3 to 50 parts by mass, and more preferably 5 to 40 parts by mass, based on 100 parts by mass of the total mass of the resin composition other than the inorganic filler.

[0089] <Other ingredients> The resin composition according to this embodiment may contain components other than those described above (other components) as necessary, as long as they do not impair the effects of the present invention. Other components contained in the resin composition according to this embodiment may further include, for example, catalysts such as reaction initiators and reaction accelerators, silane coupling agents, polymerization inhibitors, polymerization retardants, flame retardant aids, defoamers, leveling agents, antioxidants, heat stabilizers, antistatic agents, ultraviolet absorbers, dyes and pigments, dispersants and lubricants and other additives.

[0090] As described above, the resin composition according to this embodiment may contain a reaction initiator (catalyst) and a reaction accelerator. The reaction initiator and reaction accelerator are not particularly limited as long as they can accelerate the curing reaction of the resin composition. Specifically, examples include metal oxides, azo compounds, peroxides, imidazole compounds, phosphorus-based curing accelerators, amine-based curing accelerators, and the like.

[0091] Examples of metal oxides include zinc octylate, tin octylate, zinc naphthenate, cobalt naphthenate, tin stearate, and zinc stearate.

[0092] Examples of peroxides include α,α'-di(t-butylperoxy)diisopropylbenzene, 2,5-dimethyl-2,5-di(t-butylperoxy)-3-hexine, benzoyl peroxide, 3,3',5,5'-tetramethyl-1,4-diphenoquinone, chloranil, 2,4,6-tri-t-butylphenoxyl, t-butylperoxyisopropyl monocarbonate, and azobisisobutyronitrile.

[0093] Examples of azo compounds include 2,2'-azobis(2,4,4-trimethylpentane), 2,2'-azobis(N-butyl-2-methylpropionamide), and 2,2'-azobis(2-methylbutyronitrile).

[0094] Among the preferred reaction initiators, α,α'-di(t-butylperoxy)diisopropylbenzene is preferably used. α,α'-di(t-butylperoxy)diisopropylbenzene has low volatility, so it does not volatilize during drying or storage, resulting in good stability. Furthermore, because α,α'-di(t-butylperoxy)diisopropylbenzene has a relatively high reaction initiation temperature, it can suppress the acceleration of the curing reaction at points where curing is not required, such as during prepreg drying. This suppression of the curing reaction helps to prevent a decrease in the shelf life of the resin composition.

[0095] 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.

[0096] Examples of amine-based curing accelerators include trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine (DMAP), benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, and 1,8-diazabicyclo(5,4,0)-undecene.

[0097] Examples of imidazole compounds include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6-[ 2'-methylimidazolyl-(1')-ethyl-s-triazine, 2,4-diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanurate adduct, 2- Examples of imidazole compounds include phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazoline, and 2-phenylimidazoline.

[0098] The reaction initiators described above may be used individually or in combination of two or more.

[0099] If the resin composition of this embodiment contains the reaction initiator, the amount thereof is not particularly limited, but for example, it is preferably 0.01 to 5.0 parts by mass, more preferably 0.01 to 3 parts by mass, and even more preferably 0.05 to 3.0 parts by mass, based on 100 parts by mass of the total of the maleimide compound (A), the hydrocarbon compound (B), and (if the reactive compound (C) is included, the reactive compound (C)).

[0100] (Prepregs, resin-coated films, metal-clad laminates, wiring boards, and resin-coated metal foils) Next, a prepreg, metal-clad laminate, wiring board, and resin-coated metal foil for a wiring board using the resin composition of this embodiment will be described. In the drawings, each reference numeral indicates the following, respectively: 1 prepreg, 2 resin composition or semi-cured resin composition, 3 fibrous substrate, 11 metal-clad laminate, 12 insulating layer, 13 metal foil, 14 wiring, 21 wiring board, 31 resin-coated metal foil, 32, 42 resin layer, 41 resin-coated film, and 43 support film.

[0101] Figure 1 is a schematic cross-sectional view showing an example of prepreg 1 according to an embodiment of the present invention.

[0102] As shown in Figure 1, the prepreg 1 according to this embodiment comprises the resin composition or a semi-cured product 2 of the resin composition and a fibrous base material 3. An example of this prepreg 1 is one in which the fibrous base material 3 is present within the resin composition or its semi-cured product 2. That is, this prepreg 1 comprises the resin composition or its semi-cured product and the fibrous base material 3 present within the resin composition or its semi-cured product 2.

[0103] In this embodiment, "semi-cured product" refers to a resin composition that has been partially cured to the extent that it can be further cured. In other words, a semi-cured product is a resin composition that has been partially cured (stage B). For example, when a resin composition is heated, its viscosity gradually decreases at first, then curing begins, and the viscosity gradually increases. In such a case, a semi-cured state would be the state between when the viscosity begins to increase and when it is not yet completely cured.

[0104] The prepreg obtained using the resin composition according to this embodiment may include a semi-cured product of the resin composition as described above, or it may include 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 stage B) and a fibrous substrate, or it may be a prepreg comprising the uncured resin composition (the resin composition in stage A) and a fibrous substrate. Specifically, for example, a resin composition may contain a fibrous substrate. The resin composition or its semi-cured product may be obtained by heat-drying the resin composition.

[0105] The resin composition according to this embodiment is often prepared in a varnish-like form and used as a resin varnish when manufacturing the prepreg, or resin-coated metal foil or metal-clad laminate described later. Such a resin varnish is prepared, for example, as follows.

[0106] First, each component that can be dissolved in an organic solvent, such as the resin component and reaction initiator, is added to the organic solvent and dissolved. Heating may be performed as needed during this process. Subsequently, an inorganic filler or the like, which is a component that does not dissolve in the organic solvent, is added, and the mixture is dispersed using a ball mill, bead mill, planetary mixer, roll mill, etc., until a predetermined dispersion state is reached, thereby preparing a varnish-like resin composition. The organic solvent used here is not particularly limited as long as it dissolves the maleimide compound (A), the hydrocarbon compound (B), and the reactive compound (C) as needed, etc., without inhibiting the curing reaction. Specifically, examples include toluene, methyl ethyl ketone, cyclohexanone, cyclopentanone, methylcyclohexane, dimethylformamide, and propylene glycol monomethyl ether acetate. These may be used individually or in combination of two or more.

[0107] A method for producing the prepreg 1 of this embodiment using the varnish-like resin composition of this embodiment is, for example, to impregnate a fibrous substrate 3 with the resin varnish-like resin composition 2 and then dry it.

[0108] Specific examples of fibrous base materials used in the manufacture of prepregs include glass cloth, aramid cloth, polyester cloth, LCP (liquid crystal polymer) nonwoven fabric, glass nonwoven fabric, aramid nonwoven fabric, polyester nonwoven fabric, pulp paper, and linter paper. When glass cloth is used, a laminate with excellent mechanical strength can be obtained, and flattened glass cloth is particularly preferred. The glass cloth used in this embodiment is not particularly limited, but examples include low dielectric constant glass cloths such as E glass, S glass, NE glass, Q glass, and L glass. Specifically, the flattening process can be carried out, for example, by continuously pressing the glass cloth with a press roll at an appropriate pressure to flatten the yarn. The thickness of the fibrous base material can generally be 0.01 to 0.3 mm.

[0109] The resin varnish (resin composition 2) is impregnated into the fibrous substrate 3 by dipping, coating, etc. This impregnation can be repeated multiple times as needed. Furthermore, it is possible to repeat the impregnation using multiple resin varnishes with different compositions and concentrations to finally adjust to the desired composition (content ratio) and resin amount.

[0110] A fibrous substrate 3 impregnated with resin varnish (resin composition 2) is heated under desired heating conditions, for example, at 80°C or higher and 180°C or lower for 1 minute or more and 10 minutes or less. Heating causes the solvent to evaporate from the varnish, reducing or removing the solvent to obtain a prepreg 1 in a pre-cured state (Stage A) or a semi-cured state (Stage B).

[0111] Furthermore, as shown in Figure 4, the resin-coated metal foil 31 of this embodiment has a structure in which a resin layer 32 containing the above-mentioned resin composition or a semi-cured product of the resin composition and a metal foil 13 are laminated together. That is, the resin-coated metal foil of this embodiment may be a resin-coated metal foil comprising a resin layer containing the resin composition before curing (the resin composition in stage A) and a metal foil, or it may be a resin-coated metal foil comprising a resin layer containing a semi-cured product of the resin composition (the resin composition in stage B) and a metal foil.

[0112] One method for producing such resin-coated metal foil 31 is to apply a resin varnish-like resin composition, as described above, to the surface of a metal foil 13 such as copper foil, and then dry it. Examples of such application methods include bar coaters, comma coaters, die coaters, roll coaters, gravure coaters, and the like.

[0113] The metal foil 13 can be any metal foil used in metal-clad laminates, wiring boards, etc., for example, copper foil and aluminum foil.

[0114] Furthermore, as shown in Figure 5, the resin-coated film 41 of this embodiment has a structure in which a resin layer 42 containing the above-mentioned resin composition or a semi-cured product of the resin composition and a film support substrate 43 are laminated together. That is, the resin-coated film of this embodiment may be a resin-coated film comprising the resin composition before curing (the resin composition in stage A) and a film support substrate, or it may be a resin-coated film comprising a semi-cured product of the resin composition (the resin composition in stage B) and a film support substrate.

[0115] As a method for producing such a resin-coated film 41, for example, a resin varnish-like resin composition as described above can be applied to the surface of a film support substrate 43, and then the solvent can be evaporated from the varnish to reduce the amount of solvent, or the solvent can be removed, thereby obtaining a resin-coated film in a pre-cured state (Stage A) or a semi-cured state (Stage B).

[0116] Examples of the film support substrate include electrically insulating films such as polyimide film, PET (polyethylene terephthalate) film, polyethylene naphthalate film, polyester film, polyparabanic acid film, polyether ether ketone film, polyphenylene sulfide film, aramid film, polycarbonate film, and polyarylate film.

[0117] In addition, in the resin-coated film and resin-coated metal foil of this embodiment, similar to the prepreg described above, the resin composition or its semi-cured product may be obtained by drying or heat-drying the resin composition.

[0118] The thickness of the metal foil 13 and the film support substrate 43 can be set appropriately according to the desired purpose. For example, the metal foil 13 can be approximately 0.2 to 70 μm thick. If the thickness of the metal foil is, for example, 10 μm or less, a carrier-equipped copper foil with a release layer and carrier may be used to improve handling. The resin varnish is applied to the metal foil 13 and the film support substrate 43 by coating, and this can be repeated multiple times as needed. In this case, it is also possible to repeatedly coat using multiple resin varnishes with different compositions and concentrations to finally adjust to the desired composition (content ratio) and amount of resin.

[0119] The drying or heat drying conditions in the manufacturing method of the resin-coated metal foil 31 and resin-coated film 41 are not particularly limited, but after applying a resin varnish-like resin composition to the metal foil 13 or film support substrate 43, the resin is heated under desired heating conditions, for example, at 50 to 180°C for about 0.1 to 10 minutes, to volatilize the solvent from the varnish and reduce or remove the solvent, thereby obtaining the resin-coated metal foil 31 or resin-coated film 41 in a pre-cured state (A stage) or a semi-cured state (B stage).

[0120] The resin-coated metal foil 31 and the resin-coated film 41 may be provided with a cover film or the like, if necessary. Providing a cover film can prevent the incorporation of foreign matter. The cover film is not particularly limited as long as it can be peeled off without damaging the form of the resin composition, but for example, polyolefin film, polyester film, TPX film, films formed by providing a release agent layer on these films, and paper obtained by laminating these films onto a paper substrate can be used.

[0121] As shown in Figure 2, the metal-clad laminate 11 of this embodiment is characterized by having an insulating layer 12 containing a cured product of the resin composition or a cured product of the prepreg described above, and a metal foil 13. The metal foil 13 used in the metal-clad laminate 11 can be the same as the metal foil 13 described above.

[0122] Furthermore, the metal-clad laminate 11 of this embodiment can also be made using the resin-coated metal foil 31 or resin-coated film 41 described above.

[0123] As a method for producing a metal-clad laminate using the prepreg 1, resin-coated metal foil 31, or resin-coated film 41 obtained as described above, one or more sheets of the prepreg 1, resin-coated metal foil 31, or resin-coated film 41 are stacked, and then metal foil 13 such as copper foil is stacked on both sides or one side of the stack. This is then heated and pressurized to create a laminate that is metal-clad on both sides or on one side. The heating and pressurizing conditions can be appropriately set depending on the thickness of the laminate to be manufactured and the type of resin composition, but for example, the temperature can be set to 170-230°C, the pressure to 1.5-5.0 MPa, and the time to 60-150 minutes.

[0124] Alternatively, the metal-clad laminate 11 may be manufactured by forming a film-like resin composition on a metal foil 13 and then heating and pressurizing it, without using a prepreg 1 or the like.

[0125] As shown in Figure 3, the wiring board 21 of this embodiment has an insulating layer 12 containing a cured product of the resin composition or a cured product of the prepreg described above, and wiring 14.

[0126] The resin composition of this embodiment is suitably used as a material for the insulating layer of a wiring board. As a method for manufacturing the wiring board 21, for example, a wiring board 21 can be obtained by etching the metal foil 13 on the surface of the metal-clad laminate 11 obtained above to form circuits (wirings), thereby providing a conductor pattern (wirings 14) as a circuit on the surface of the laminate. In addition to the method described above, other methods for forming circuits include, for example, circuit formation by the semi-additive process (SAP) or the modified semi-additive process (MSAP).

[0127] The prepregs, resin-coated films, and resin-coated metal foils obtained using the resin composition of this embodiment are extremely useful for industrial applications because, in their cured form, they possess excellent low dielectric properties and high Tg while also suppressing water absorption. Furthermore, the metal-clad laminates and wiring boards obtained by curing them have the advantage of possessing low dielectric properties and high Tg, and suppressing moisture absorption.

[0128] The present invention will be described in more detail below with reference to examples, but the scope of the present invention is not limited thereto. [Examples]

[0129] First, the components used in preparing the resin composition in this embodiment will be described.

[0130] (Maleimide compound (A)) Maleimide compound 1: A maleimide compound represented by formula (3) above (a maleimide compound having an indane structure in its molecule).

[0131] Specifically, it is a maleimide compound synthesized as follows:

[0132] First, 48.5 g (0.4 mol) of 2,6-dimethylaniline, 272.0 g (1.4 mol) of α,α'-dihydroxy-1,3-diisopropylbenzene, 280 g of xylene, and 70 g of activated clay were charged into a 1 L flask equipped with a thermometer, condenser, Dean-Stark tube, and stirrer, and heated to 120°C while stirring. Further heating was carried out to 210°C while removing the distillate using a Dean-Stark tube. The reaction was carried out in this manner for 6 hours. After that, the mixture was cooled to 140°C, and 145.4 g (1.2 mol) of 2,6-dimethylaniline was charged, followed by heating to 220°C. The reaction was carried out in this manner for 3 hours. After the reaction, the mixture was air-cooled to 100°C, diluted with 300 g of toluene, the activated clay was removed by filtration, and 345.2 g of solid was obtained by distilling off the solvent and unreacted low molecular weight substances under reduced pressure. The obtained solid was an amine compound represented by the following formula (9) (amine equivalent 348, softening point 71°C).

[0133] [ka]

[0134] Next, 131.8 g (1.3 mol) of maleic anhydride and 700 g of toluene were charged into a 2 L flask equipped with a thermometer, condenser, Dean-Stark tube, and stirrer, and stirred at room temperature. Then, a mixed solution of 345.2 g of the amine compound represented by formula (9) and 175 g of DMF was added dropwise over 1 hour. After the addition was complete, the mixture was stirred at room temperature for a further 2 hours to allow the reaction to proceed. Subsequently, 37.1 g of p-toluenesulfonic acid monohydrate was added, and the reaction mixture was heated under reflux. The azeotropic formation of water and toluene was cooled and separated, and only toluene was returned to the system to carry out the dehydration reaction for 8 hours. After air cooling to room temperature, the mixture was concentrated under reduced pressure, and the brown solution was dissolved in 600 g of ethyl acetate. The mixture was washed three times with 150 g of deionized water and three times with 150 g of 2% sodium bicarbonate aqueous solution. Sodium sulfate was added, the mixture was dried, and the reaction product was concentrated under reduced pressure. The resulting product was vacuum-dried at 80°C for 4 hours to obtain 407.6 g of solid. The obtained solid was analyzed using FD-MS spectroscopy and GPC, and was found to be a maleimide compound represented by formula (3) above (n = 2.59, molecular weight distribution (Mw / Mn) = 1.49).

[0135] Maleimide compound 2: A maleimide compound represented by formula (3) above (a maleimide compound having an indane structure in its molecule).

[0136] Specifically, it is a maleimide compound synthesized as follows:

[0137] First, 48.5 g (0.4 mol) of 2,6-dimethylaniline, 272.0 g (1.4 mol) of α,α'-dihydroxy-1,3-diisopropylbenzene, 280 g of xylene, and 70 g of activated clay were charged into a 1 L flask equipped with a thermometer, condenser, Dean-Stark tube, and stirrer, and heated to 120°C while stirring. Further heating was carried out to 210°C while removing the distillate using a Dean-Stark tube. The reaction was carried out in this manner for 3 hours. After that, the mixture was cooled to 140°C, and 145.4 g (1.2 mol) of 2,6-dimethylaniline was charged, followed by heating to 220°C. The reaction was carried out in this manner for 3 hours. After the reaction, the mixture was air-cooled to 100°C, diluted with 300 g of toluene, the activated clay was removed by filtration, and 364.1 g of solid was obtained by distilling off the solvent and unreacted low molecular weight substances under reduced pressure. The obtained solid was an amine compound represented by the following formula (10) (amine equivalent 298, softening point 70°C).

[0138] [ka]

[0139] Next, 131.8 g (1.3 mol) of maleic anhydride and 700 g of toluene were charged into a 2 L flask equipped with a thermometer, condenser, Dean-Stark tube, and stirrer, and stirred at room temperature. Then, a mixed solution of 364.1 g of the amine compound represented by formula (10) and 175 g of DMF was added dropwise over 1 hour. After the addition was complete, the mixture was stirred at room temperature for a further 2 hours to allow the reaction to proceed. Subsequently, 37.1 g of p-toluenesulfonic acid monohydrate was added, and the reaction mixture was heated under reflux. The azeotropic formation of water and toluene was cooled and separated, and only toluene was returned to the system to carry out the dehydration reaction for 8 hours. After air cooling to room temperature, the mixture was concentrated under reduced pressure, and the brown solution was dissolved in 600 g of ethyl acetate. The mixture was washed three times with 150 g of deionized water and three times with 150 g of 2% sodium bicarbonate aqueous solution. Sodium sulfate was added, the mixture was dried, and the reaction product was concentrated under reduced pressure. The resulting product was vacuum-dried at 80°C for 4 hours to obtain 413.0 g of solid. The obtained solid was analyzed using FD-MS spectroscopy and GPC, and was found to be a maleimide compound represented by formula (3) above (n = 1.47, molecular weight distribution (Mw / Mn) = 1.81).

[0140] (Hydrogen compounds (B)) • Production of hydrocarbon compound 1 First, the weight-average molecular weight (Mw) and number-average molecular weight (Mn) used in the production of hydrocarbon compound 1 below were determined by the following analytical method.

[0141] (Analysis method) The calculation was performed using polystyrene standard solutions and converted to polystyrene equivalents.

[0142] GPC: DGU-20A3R, LC-20AD, SIL-20AHT, RID-20A, SPD-20A, CTO-2, CBM-20A (all manufactured by Shimadzu Corporation) Columns: Shodex KF-603, KF-602 x2, KF-601 x2) Linking eluent: tetrahydrofuran Flow rate: 0.5ml / min. Column temperature: 40℃ Detection: RI (Differential Refraction Detector)

[0143] (Synthesis Example 1) 296 parts of 2-bromoethylbenzene (Tokyo Chemical Industries, Ltd.), 70 parts of α,α'-dichloro-p-xylene (Tokyo Chemical Industries, Ltd.), and 18.4 parts of methanesulfonic acid (Tokyo Chemical Industries, Ltd.) were charged into a flask equipped with a thermometer, condenser, and stirrer, and the mixture was reacted at 130°C for 8 hours. After cooling, the mixture was neutralized with an aqueous sodium hydroxide solution, extracted with 1200 parts of toluene, and the organic layer was washed five times with 100 parts of water. By distilling off the solvent and excess 2-bromoethylbenzene under heated reduced pressure, 160 parts of an olefin compound precursor (BEB-1) having a 2-bromoethylbenzene structure was obtained as a liquid resin (Mn: 538, Mw: 649). The GPC chart of the obtained compound is shown in Figure 6. The repeating unit n, calculated from the area % of the GPC chart, was 1.7. The 1H-NMR chart (DMSO-d6) of the obtained compound is shown in Figure 7. 1 Signals originating from the bromoethyl group were observed at 2.95–3.15 ppm and 3.60–3.75 ppm in the 1H-NMR chart.

[0144] (Synthesis Example 2) Next, 22 parts of BEB-1 obtained in Synthesis Example 1, 50 parts of toluene, 150 parts of dimethyl sulfoxide, 15 parts of water, and 5.4 parts of sodium hydroxide were added to a flask equipped with a thermometer, condenser, and stirrer, and the reaction was carried out at 40°C for 5 hours. After cooling, 100 parts of toluene were added, the organic layer was washed five times with 100 parts of water, and the solvent was removed by distillation under reduced pressure and heating to obtain 13 parts of a liquid olefin compound having a styrene structure as a functional group (Mn: 432, Mw: 575). The GPC chart of the obtained compound is shown in Figure 8. The repeating unit n calculated from the area % of the GPC chart was 1.7. The 1H-NMR data (DMSO-d6) of the obtained compound is shown in Figure 9. 1 Signals originating from vinyl groups were observed at 5.10–5.30 ppm, 5.50–5.85 ppm, and 6.60–6.80 ppm in the 1H-NMR chart.

[0145] The aforementioned liquid olefin compound was designated as hydrocarbon compound 1.

[0146] (styrene) • Styrene (B1: Reagent manufactured by Wako Pure Chemical Industries, Ltd.) (Diene polymer) • Diene polymer (polybutadiene, B-3000: manufactured by Nippon Soda Co., Ltd.)

[0147] (Reactive compound (C)) • Maleimide compound (D) (Solid content in MIR-3000-70MT, manufactured by Nippon Kayaku Co., Ltd.) • Polyphenylene ether compound (OPE-2st 1200, a polyphenylene ether compound having a vinylbenzyl group (ethenylbenzyl group) at the terminal end, manufactured by Mitsubishi Gas Chemical Company, Inc.)

[0148] (Reaction initiators / reaction accelerators) • Peroxides (Perkmill D, Dicumyl Peroxide, manufactured by NOF Corporation) (Flame retardant) • Aromatic condensed phosphate ester (PX-200, manufactured by Daihachi Chemical Industry Co., Ltd.) (Inorganic fillers) • Silica particles: "SO-C2" spherical silica (manufactured by Admatex Co., Ltd.)

[0149] <Examples 1-6, Comparative Examples 1-2> [Preparation method] (Resin varnish) First, the resin components (maleimide compounds, hydrocarbon compounds, reactive compounds, etc.) were added to toluene in the proportions (parts by mass) shown in Table 1, so that the solid content concentration was 50% by mass, and then mixed. Depending on the sample, a reaction initiator and inorganic filler were added to the mixture, and after stirring for 60 minutes, the mixture was dispersed using a bead mill to obtain a resin varnish.

[0150] (Creation of evaluation board) The prepreg and evaluation substrate (metal-clad laminate) were obtained as follows.

[0151] First, the obtained varnish was impregnated into a fibrous substrate (glass cloth: #2116 type, L glass, manufactured by Asahi Kasei Corporation), and then heated and dried at 120°C for 3 minutes to produce a prepreg. At that time, the content of the components constituting the resin composition relative to the prepreg (resin content) was adjusted to 50% by mass due to the curing reaction.

[0152] Next, an evaluation substrate (metal-clad laminate) was obtained as follows.

[0153] Two of the obtained prepregs were stacked together, and copper foil (Furukawa Electric Co., Ltd.'s "FV-WS" copper foil, thickness: 18 μm) was placed on both sides. This was used as the pressure-bearing body, and it was heated to a temperature of 220°C at a heating rate of 4°C / min. By heating and pressurizing it at 220°C for 120 minutes under a pressure of 2 MPa, an evaluation substrate (metal-clad laminate) with a resin layer thickness of approximately 250 μm was obtained, with copper foil bonded to both sides.

[0154] Using the prepreg and evaluation substrate (metal-clad laminate) prepared as described above, evaluation tests were conducted using the method shown below.

[0155] <Evaluation Test 1> (Glass transition temperature (Tg)) Using an unclad plate obtained by etching away the copper foil from the evaluation substrate described above, the Tg was measured using a Seiko Instruments Inc. viscoelastic spectrometer "DMS100". Dynamic viscoelasticity measurement (DMA) was performed using a tensile module at a frequency of 10 Hz. Tg was defined as the temperature at which tanδ was maximum when the temperature was increased from room temperature to 350°C at a heating rate of 5°C / min. In this test, a Tg of 250°C or higher was considered acceptable. Since Tg was only evaluated up to 350°C, values ​​exceeding 350°C are indicated as ">350".

[0156] (Dielectric properties: relative permittivity (Dk) and dielectric loss tangent (Df)) An unclad board, obtained by etching away the copper foil from the aforementioned evaluation substrate (metal-clad laminate), was used as a test specimen, and the relative permittivity and dielectric loss tangent at 10 GHz were measured using the cavity resonator perturbation method. Specifically, a network analyzer (N5230A manufactured by Keysight Technologies, Inc.) was used to measure the relative permittivity and dielectric loss tangent of the evaluation substrate at 10 GHz. In this test, a pass was defined as a Dk of less than 3.5 and a Df of less than 0.0035.

[0157] (Water absorption rate) Unclad plates, obtained by etching away the copper foil from the aforementioned evaluation substrate (metal-clad laminate), were used as test specimens, and the water absorption rate (%) was measured according to the method compliant with IPC-TM-650 2.6.2.1. In this test, a water absorption rate of less than 0.4% was considered acceptable.

[0158] The results are shown in Table 1.

[0159] [Table 1]

[0160] (Consideration) As is clear from the results shown in Table 1, it was confirmed that the resin composition of the present invention yields a cured product with low dielectric properties, high Tg, and low water absorption.

[0161] In contrast, Comparative Example 1, which used a maleimide compound without an indan structure, exceeded the passing criteria for high Tg and low dielectric constant, but the dielectric loss tangent (Df) did not meet the passing criteria for this test, and the water absorption rate was also high. Similarly, Comparative Example 2, which did not contain the hydrocarbon compound (B) represented by formula (1), also showed high values ​​for dielectric loss tangent and water absorption rate, and did not meet the passing criteria.

[0162] <Evaluation Test 2> (Coefficient of thermal expansion (CTE)) An unclad plate, obtained by etching away the copper foil from the aforementioned evaluation substrate (metal-clad laminate), was used as a test specimen. The coefficient of thermal expansion in the substrate direction (tensile direction, Y direction) at temperatures below the glass transition temperature of the resin cured product was measured by the TMA method (Thermo-mechanical analysis). Specifically, a TMA device (TMA6000, manufactured by SII Nanotechnology Co., Ltd.) was used for measurement in tensile mode. To eliminate the effect of thermal strain on the test specimen, the heating-cooling cycle was repeated twice, and the average coefficient of thermal expansion from 50°C to 100°C on the second temperature displacement chart was measured. A smaller value indicates a more favorable result. The unit is ppm / °C. [Measurement conditions] • 1st cycle: Temperature increase range 30℃ → 275℃ Heating rate: 20°C / min, Load: 10g • 2nd cycle: Temperature increase range 30℃ → 300℃ Heating rate: 10°C / min, Load: 10g The results are shown in Table 2.

[0163] [Table 2]

[0164] (Consideration) The results in Table 2 show that, compared to Example 1, Examples 4 and 5 exhibited improved low thermal expansion properties due to the inclusion of the reactive compound (C). Furthermore, the results in Example 6 confirmed that the inclusion of an inorganic filler resulted in a very low coefficient of thermal expansion.

[0165] This application is based on Japanese Patent Application No. 2021-83146, filed on 17 May 2021, the contents of which are included in this application.

[0166] In order to express the present invention, the invention has been adequately and sufficiently described above through embodiments with reference to specific examples and drawings, etc. However, those skilled in the art should recognize that it is easy to modify and / or improve the embodiments described above. Therefore, unless the modifications or improvements implemented by those skilled in the art fall outside the scope of the claims described in the claims, such modifications or improvements shall be interpreted as being included within the scope of the claims. [Industrial applicability]

[0167] The present invention has broad industrial applicability in the technical fields of electronic materials, electronic devices, optical devices, and the like.

Claims

1. A maleimide compound (A) having an indane structure in its molecule, A hydrocarbon compound (B) represented by the following formula (1) contains, 【Chemistry 1】 [In formula (1), X represents a hydrocarbon group having 6 or more carbon atoms, comprising at least one selected from aromatic cyclic groups and aliphatic cyclic groups. n represents an integer from 1 to 10.] A resin composition wherein the hydrocarbon compound (B) comprises a hydrocarbon compound (B1) represented by the following formula (4). 【Chemistry 4】 [n represents an integer between 1 and 10.]

2. The resin composition according to claim 1, wherein the indan structure includes a structure represented by the following formula (2). 【Chemistry 2】 [In formula (2), Rb independently represents a C1-C10 alkyl group, a C1-C10 alkyloxy group, a C1-C10 alkylthio group, a C6-C10 aryl group, a C6-C10 aryloxy group, a C6-C10 arylthio group, a C3-C10 cycloalkyl group, a halogen atom, a hydroxyl group, or a mercapto group. r represents an integer from 0 to 3.]

3. The resin composition according to claim 1, wherein the maleimide compound (A) comprises a maleimide compound (A1) represented by the following formula (3). 【Transformation 3】 [In formula (3), Ra independently represents a C1-C10 alkyl group, a C1-C10 alkyloxy group, a C1-C10 alkylthio group, a C6-C10 aryl group, a C6-C10 aryloxy group, a C6-C10 arylthio group, a C3-C10 cycloalkyl group, a halogen atom, a nitro group, a hydroxyl group, or a mercapto group. Rb independently represents a C1-C10 alkyl group, a C1-C10 alkyloxy group, a C1-C10 alkylthio group, a C6-C10 aryl group, a C6-C10 aryloxy group, a C6-C10 arylthio group, a C3-C10 cycloalkyl group, a halogen atom, a nitro group, a hydroxyl group, or a mercapto group. q represents an integer from 0 to 4, r represents an integer from 0 to 3, and n represents an integer from 0.95 to 10.]

4. The resin composition according to claim 1, wherein the content of the maleimide compound (A) is 20 to 80 parts by mass with respect to 100 parts by mass of the total mass of the maleimide compound (A) and the hydrocarbon compound (B).

5. The resin composition according to claim 1, comprising a reactive compound (C) that reacts with at least one of the maleimide compound (A) and the hydrocarbon compound (B).

6. The resin composition according to claim 5, wherein the reactive compound (C) comprises at least one selected from the group consisting of a maleimide compound (D) different from the maleimide compound (A), an epoxy compound, a methacrylate compound, an acrylate compound, a vinyl compound, a cyanate ester compound, an active ester compound, an allyl compound, a benzoxazine compound, a phenol compound, and a polyphenylene ether compound.

7. The resin composition according to claim 5, wherein the content of the hydrocarbon compound (B) is 5 to 50 parts by mass with respect to 100 parts by mass of the total of the maleimide compound (A), the hydrocarbon compound (B), and the reactive compound (C).

8. The resin composition according to claim 5, wherein the content of the reactive compound (C) is 1 to 40 parts by mass with respect to 100 parts by mass of the total of the maleimide compound (A), the hydrocarbon compound (B), and the reactive compound (C).

9. The resin composition according to claim 1, comprising an inorganic filler.

10. The resin composition according to claim 1, comprising a phosphorus-based flame retardant.

11. A prepreg having a resin composition according to any one of claims 1 to 10 or a semi-cured product of the resin composition and a fibrous substrate.

12. A resin-coated film having a resin layer containing the resin composition according to any one of claims 1 to 10 or a semi-cured product of the resin composition, and a support film.

13. A resin-coated metal foil having a resin layer containing the resin composition according to any one of claims 1 to 10 or a semi-cured product of the resin composition, and a metal foil.

14. A metal-clad laminate having an insulating layer containing a cured resin composition according to any one of claims 1 to 10, and a metal foil.

15. A wiring substrate having an insulating layer containing a cured product of the resin composition according to any one of claims 1 to 10, and wiring.

16. A metal-clad laminate having an insulating layer containing a cured prepreg according to claim 11 and a metal foil.

17. A wiring substrate having an insulating layer containing a cured prepreg according to claim 11, and wiring.

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