Resin compositions, prepregs, resin-coated films, resin-coated metal foils, metal-clad laminates, and wiring boards

Abstract

To provide a resin composition that yields a cured product with a low relative dielectric constant and a low thermal expansion coefficient, and also provide a prepreg, a film with resin, a metal foil with resin, a metal-clad laminate, and a wiring board, each prepared using the resin composition.SOLUTION: A resin composition includes at least one curable compound (A) selected from the group consisting of maleimide compounds, benzoxazine compounds, and hydrocarbon-based compounds, and polysilsesquioxane particles (B). The polysilsesquioxane particles (B) include a structural unit represented by formula (1) in a specific amount within their molecules. In formula (1), R1 is an alkyl group or an aryl group.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to resin compositions, prepregs, resin-coated films, resin-coated metal foils, metal-clad laminates, and wiring boards. [Background technology]

[0002] As the amount of information processing required for various electronic devices increases, mounting technologies such as high integration, high-density wiring, and multi-layering of the semiconductor devices they incorporate are rapidly advancing. Furthermore, the wiring boards used in various electronic devices are required to be high-frequency compatible, such as millimeter-wave radar substrates for automotive applications. The substrate material that constitutes the insulating layer of the wiring boards used in various electronic devices is required to have low relative permittivity and dielectric loss tangent in order to increase the signal transmission speed and reduce signal loss during signal transmission.

[0003] Examples of substrate materials with low relative permittivity and dielectric loss tangent include resin compositions containing curable compounds, and more specifically, resin compositions described in Patent Document 1.

[0004] Patent Document 1 describes a polyphenylene ether resin composition comprising an ethenyl benzylated polyphenylene ether having a number average molecular weight of 1,000 to 7,000 and a crosslinking curing agent. According to Patent Document 1, a polyphenylene ether resin composition can be obtained that allows for the production of highly heat-resistant laminates without reducing dielectric properties, even when using a polyphenylene ether with a low molecular weight. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Special Publication No. 2006-516297 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] Metal-clad laminates and resin-coated metal foils used in the manufacture of wiring boards, etc., have not only an insulating layer but also metal foil on the insulating layer. Similarly, wiring boards also have not only an insulating layer but also wiring on the insulating layer. The wiring can be said to be derived from the metal foil provided on the metal-clad laminate, etc.

[0007] In recent years, there has been a rapid increase in the functionality, performance, thinning, and miniaturization of small portable devices, particularly mobile communication terminals and notebook PCs. Consequently, the printed circuit boards used in these products are required to have finer conductor wiring, multi-layered conductor wiring layers, thinner designs, and improved mechanical properties. In particular, as printed circuit boards become thinner, there is a problem of warping occurring in semiconductor packages on which semiconductor chips are mounted, leading to increased mounting defects. To suppress warping of semiconductor packages on which semiconductor chips are mounted, the insulating layer must have a low coefficient of thermal expansion. Therefore, the substrate material used to form the insulating layer of the printed circuit board must yield a cured product with a low coefficient of thermal expansion. Furthermore, with the thinning of printed circuit boards, a low relative permittivity is also required for the insulating layer constituting the printed circuit board, from the viewpoint of facilitating impedance matching.

[0008] The present invention has been made in view of the above circumstances and aims to provide a resin composition that yields a cured product with a low dielectric constant and a low coefficient of thermal expansion. 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 that can be obtained using the above resin composition. [Means for solving the problem]

[0009] As a result of various studies, the inventors have found that the above objective can be achieved by the present invention described below.

[0010] A resin composition according to one aspect of the present invention comprises a curable compound (A) containing at least one selected from the group consisting of maleimide compounds, benzoxazine compounds, and hydrocarbon compounds, and polysilsesquioxane particles (B), wherein the polysilsesquioxane particles (B) have in their molecule a structural unit represented by the following formula (1) and at least one selected from the following structural units represented by formulas (2) to (5), the ratio of the number of Si atoms contained in the structural unit represented by formula (1) to the total number of Si atoms contained in each of the following structural units represented by formulas (1) to (5) in the polysilsesquioxane particles (B) is 70% or more and less than 100%, and the ratio of the total number of Si atoms contained in each of the following structural units represented by formulas (2) to (4) to the total number of Si atoms contained in each of the following structural units represented by formulas (1) to (5) in the polysilsesquioxane particles (B) is greater than 0% and less than or equal to 20%.

[0011] [ka]

[0012] In formula (1), R1 represents an alkyl group or an aryl group.

[0013] [ka]

[0014] In formula (2), R2 represents an alkyl group or an aryl group.

[0015] [ka]

[0016] [ka]

[0017] [ka] [Effects of the Invention]

[0018] According to the present invention, it is possible to provide a resin composition that yields a cured product with a low dielectric constant and a low coefficient of thermal expansion. Furthermore, according to the present invention, a prepreg, a resin-coated film, a resin-coated metal foil, a metal-clad laminate, and a wiring board can be obtained using the resin composition. [Brief explanation of the drawing]

[0019] [Figure 1] Figure 1 is a schematic cross-sectional view showing an example of a prepreg according to an embodiment of the present invention. [Figure 2] Figure 2 is a schematic cross-sectional view showing an example of a metal-clad laminate according to an embodiment of the present invention. [Figure 3] Figure 3 is a schematic cross-sectional view showing an example of a wiring board according to an embodiment of the present invention. [Figure 4] Figure 4 is a schematic cross-sectional view showing an example of a resin-coated metal foil according to an embodiment of the present invention. [Figure 5] Figure 5 is a schematic cross-sectional view showing an example of a resin-coated film according to an embodiment of the present invention. [Modes for carrying out the invention]

[0020] The embodiments of the present invention will be described below, but the present invention is not limited thereto.

[0021] [Resin composition] A resin composition according to one embodiment of the present invention is a resin composition comprising a curable compound (A) and polysilsesquioxane particles (B), which will be described later.

[0022] (Curable compound (A)) The curable compound (A) is not particularly limited as long as it is at least one selected from the group consisting of maleimide compounds (A1), benzoxazine compounds (A2), and hydrocarbon compounds (A3). The curable compound (A) may contain one of the maleimide compounds (A1), benzoxazine compounds (A2), and hydrocarbon compounds (A3), or it may contain two or more of them. Furthermore, the curable compound (A) may contain one of each of the maleimide compounds (A1), benzoxazine compounds (A2), and hydrocarbon compounds (A3), or it may contain two or more of them.

[0023] (Maleimide compound (A1)) The maleimide compound (A1) is not particularly limited as long as it is a compound having a maleimide group in its molecule. Examples of the maleimide compound (A1) include monofunctional maleimide compounds having one maleimide group in their molecule, polyfunctional maleimide compounds having two or more maleimide groups in their molecule, and modified maleimide compounds. Examples of the modified maleimide compounds include modified maleimide compounds in which part of the molecule is modified with an amine compound, modified maleimide compounds in which part of the molecule is modified with a silicone compound, and modified maleimide compounds in which part of the molecule is modified with both an amine compound and a silicone compound.

[0024] Examples of the maleimide compound (A1) include a maleimide compound (A1-1) having an indane structure in its molecule. Examples of the indane structure include a divalent group formed by removing two hydrogens from indane or indane substituted with substituents, and specifically, a structure represented by the following formula (7) is an example. That is, examples of the maleimide compound (A1-1) include a maleimide compound having a structure represented by the following formula (7) in its molecule. The maleimide compound (A1-1) also has a maleimide group in its molecule.

[0025] [ka]

[0026] In formula (7), each Rb is independent. That is, each Rb may be the same group or a different group. For example, when 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). r represents 0 to 3.

[0027] More specifically, the maleimide compound (A1-1) includes maleimide compounds having a structure represented by the following formula (8) in their molecule.

[0028] [ka]

[0029] 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 (7), 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 represents 0-4. r represents 0-3. n represents 0.95-10.

[0030] 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 (A1-1) with r = 0 is 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. 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. By using C1-C4 alkyl groups, C3-C6 cycloalkyl groups, and C6-C10 aryl groups, solubility in solvents is improved, and a 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.

[0031] The groups represented by Ra and Rb specifically include the following:

[0032] The C1-C10 alkyl group is not particularly limited, and examples include methyl, ethyl, propyl, hexyl, and decyl groups.

[0033] 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.

[0034] 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.

[0035] The aryl group having 6 to 10 carbon atoms is not particularly limited, and examples include a phenyl group and a naphthyl group.

[0036] The aryloxy group having 6 to 10 carbon atoms is not particularly limited, and examples include a phenyloxy group and a naphthyloxy group.

[0037] The arylthio group having 6 to 10 carbon atoms is not particularly limited, and examples include a phenylthio group and a naphthylthio group.

[0038] 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.

[0039] Examples of the halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms.

[0040] q is the average degree of substitution of Ra, preferably 2 to 3, and more preferably 2. Maleimide compounds with such a q are 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.

[0041] 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. In the maleimide compound represented by formula (7) and the maleimide compound represented by formula (8), 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.

[0042] The maleimide compound 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, as determined by GPC measurement.

[0043] Examples of the maleimide compound (A1-1) include maleimide compounds represented by formulas (9) to (11).

[0044] [ka]

[0045] In equation (9), n represents a range of 0.95 to 10.

[0046] [ka]

[0047] In equation (10), n represents a range of 0.95 to 10.

[0048] [ka]

[0049] In equation (11), n ​​represents a range of 0.95 to 10.

[0050] The method for producing the maleimide compound (A1-1) is not particularly limited as long as it can produce the maleimide compound. Specifically, the maleimide compound is obtained by a so-called maleimidation reaction, in which an amine compound represented by the following formula (12) 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 maleimidation 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.

[0051] [ka]

[0052] In formula (12), 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 (7), 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 represents 0-4. r represents 0-3. n represents 0.95-10.

[0053] The amine compound represented by formula (12) 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.

[0054] The maleimide compound (A1) is not limited to the maleimide compound (A1-1), but also includes maleimide compounds (A1-2) other than the maleimide compound (A1-1). Examples of maleimide compounds (A1-2) other than the maleimide compound (A1-1) include maleimide compounds that have a maleimide group in their molecule and do not have an indane structure in their molecule. Examples of maleimide compounds (A1-2) include maleimide compounds that have one or more maleimide groups in their molecule, and modified maleimide compounds. The maleimide compound (A1-2) is not particularly limited as long as it is a maleimide compound that has one or more maleimide groups in its molecule and does not have an indane structure in its molecule. Examples of the maleimide compounds (A1-2) include, for example, phenyl maleimide compounds such as 4,4'-diphenylmethanebismaleimide, polyphenylmethanemaleimide, m-phenylenebismaleimide, bisphenol A diphenyl ether bismaleimide, 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 compounds include, for example, 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, the solid content in MIR-3000-70MT and MIR-5000-60T manufactured by Nippon Kayaku Co., Ltd., BMI-4000 and BMI-5100 manufactured by Yamato Kasei Kogyo Co., Ltd., and BMI-689, BMI-1500, BMI-3000J, and BMI-5000 manufactured by Designer Molecules Inc. may be used.

[0055] (Benzoxazine compound (A2)) The benzoxazine compound (A2) is not particularly limited as long as it is a compound having a benzoxazine group in its molecule. The benzoxazine compound (A2) may be, for example, a benzoxazine resin. As the benzoxazine compound (A2), commercially available products can be used, for example, JBZ-OP100D and ODA-BOZ manufactured by JFE Chemical Corporation, Pd, Fa, ALP-d manufactured by Shikoku Chemicals, Inc., and HFB2006M manufactured by Showa Polymer Co., Ltd.

[0056] (Hydrogen compounds (A3)) The hydrocarbon compound (A3) is not particularly limited as long as it is a thermosetting hydrocarbon compound. Examples of the hydrocarbon compound (A3) include the hydrocarbon compound represented by the following formula (6).

[0057] [ka]

[0058] In formula (6), 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 1 to 10.

[0059] The aromatic cyclic group is not particularly limited, but examples include phenylene, xylylene, naphthylene, torylene, and biphenylene groups. The aliphatic cyclic group is not particularly limited, but examples include groups containing an indan structure and groups containing a cycloolefin structure. Among these, the aromatic cyclic group is preferred for X, and the xylylene group is more preferred. The number of carbon atoms in the hydrocarbon group is not particularly limited as long as it is 6 or more, but is preferably 6 to 20.

[0060] More specifically, examples of hydrocarbon compounds represented by formula (6) include hydrocarbon compounds represented by the following formula (13). Furthermore, it is preferable that the hydrocarbon compound (A3) includes a hydrocarbon compound represented by the following formula (13).

[0061] [ka]

[0062] In equation (13), n represents values ​​from 1 to 10.

[0063] Examples of the hydrocarbon compound (A3) include aromatic polymers having structural units derived from difunctional aromatic compounds, such as divinyl aromatic compounds, which have two carbon-carbon unsaturated double bonds bonded to an aromatic ring. The structural units derived from the difunctional aromatic compounds are structural units obtained by polymerizing the difunctional aromatic compounds. Preferred difunctional aromatic compounds include, for example, divinylbenzene such as m-divinylbenzene and p-divinylbenzene, with p-divinylbenzene being more preferred. The aromatic polymer may have structural units other than those derived from the difunctional aromatic compounds. Examples of these other structural units include structural units derived from monofunctional aromatic compounds, such as monovinyl aromatic compounds, which have one carbon-carbon unsaturated double bond bonded to an aromatic ring. Examples of monovinyl aromatic compounds include ethyl vinyl aromatic compounds. The structural units derived from the monofunctional aromatic compounds are structural units obtained by polymerizing the monofunctional aromatic compounds. The aromatic polymer may have structural units derived from the difunctional aromatic compound, or, if it has other structural units, it may be a copolymer of structural units derived from the difunctional aromatic compound and other structural units, such as structural units derived from the monofunctional aromatic compound. This copolymer may be a block copolymer or a random copolymer. Examples of the hydrocarbon compound (A3) include the aromatic polymer as described above, among which, for example, a polyfunctional vinyl aromatic copolymer is included. Examples of the polyfunctional vinyl aromatic copolymer include a copolymer having repeating units (a) derived from a divinyl aromatic compound and repeating units (b) derived from a monovinyl aromatic compound. The content of the repeating units (a) and the repeating units (b) in the polyfunctional vinyl aromatic copolymer is not particularly limited, but when the total of the repeating units (a) and the repeating units (b) is 100 mol%, it is preferable, for example, to contain 2 mol% or more and less than 95 mol% of the repeating units (a) and 5 mol% or more and less than 98 mol% of the repeating units (b).Further, the molecular weight of the polyfunctional vinyl aromatic copolymer is not particularly limited, but for example, the number average molecular weight (Mn) is preferably 300 to 10,000. Examples of the polyfunctional vinyl aromatic copolymer include polyfunctional vinyl aromatic copolymers described in Japanese Patent Application Laid-Open No. 2018-168347. Further, the hydrocarbon compound (A3) preferably contains at least one of the polyfunctional vinyl aromatic copolymer and the hydrocarbon compound represented by the formula (6).

[0064] (Polysilsesquioxane particles (B)) The polysilsesquioxane particles (B) have a structural unit represented by the following formula (1) (T 3 structure) and at least one structural unit selected from the group consisting of structural units represented by the following formulas (2) to (5) [the structural unit represented by the following formula (2) (T 2 structure), the structural unit represented by the following formula (3) (Q 2 structure), the structural unit represented by the following formula (4) (Q 3 structure), and the structural unit represented by the following formula (5) (Q 4 structure)] in the molecule.

[0065] In the polysilsesquioxane particles (B), the ratio of the number of Si atoms contained in the structural unit represented by the following formula (1) to the total number of Si atoms contained in each of the structural units represented by the following formulas (1) to (5) is 70% or more and less than 100%. That is, the T 3 the number of Si atoms contained in the structure, the T 3 structure, the T 2 structure, the Q 2 structure, the Q 3 structure, and the Q 4 ratio of the number of Si atoms contained in each structure to the total number of Si atoms [T 3 / (T 3 +T 2 +Q 2 +Q 3 +Q 4 )] is 70% or more and less than 100%.

[0066] In the polysilsesquioxane particles (B), the ratio of the total number of Si atoms contained in each of the structural units represented by the following formulas (2) to (4) to the total number of Si atoms contained in each of the structural units represented by the following formulas (1) to (5) is greater than 0% and less than or equal to 20%. That is, the T 2 Structure, Q 2 Structure, and the aforementioned Q 3 The total number of Si atoms contained in each of the structures, T 3 Structure, T 2 Structure, Q 2 Structure, Q 3 Structure, and the aforementioned Q 4 The ratio of the total number of Si atoms contained in each structure [(T 2 +Q 2 +Q 3 ) / (T 3 +T 2 +Q 2 +Q 3 +Q 4 The percentage is between 0% and 20%.

[0067] The polysilsesquioxane particles (B) are not particularly limited as long as they have structural units represented by the following formula (1) in the molecule in the above ratio, and further have at least one selected from the structural units represented by the following formulas (2) to (5) in the molecule in the above ratio. That is, in the polysilsesquioxane particles (B), the T 3 Having a structure in the molecule, the T 2 Structure, Q 2 Structure, Q 3 Structure, and the aforementioned Q 4 If any of the structures are present in the molecule in the above ratio, then the T 2 Structure, Q 2 Structure, Q 3 Structure, and Q 4 The structure may include structures that are not present within the molecule. Furthermore, the polysilsesquioxane particles (B) are T 3 Structure, T 2 Structure, Q 2 Structure, Q 3 Structure, and the aforementioned Q4 As long as the molecule contains the structures in the above-mentioned ratios, it may also have structures other than those listed above.

[0068] [ka]

[0069] In formula (1), R1 represents an alkyl group or an aryl group.

[0070] [ka]

[0071] In formula (2), R2 represents an alkyl group or an aryl group.

[0072] [ka]

[0073] [ka]

[0074] [ka]

[0075] The alkyl group is not particularly limited, but for example, an alkyl group having 1 to 30 carbon atoms is preferred, and an alkyl group having 1 to 18 carbon atoms is more preferred. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a hexyl group, and a decyl group, among which the methyl group is preferred. The aryl group is not particularly limited, but for example, an aryl group having 6 to 10 carbon atoms is preferred. Examples of the aryl group include a phenyl group and a naphthyl group, among which the phenyl group is preferred. The alkyl groups are preferred for R1 and R2, and a methyl group is more preferred. R1 and R2 may be any one of these groups or a combination of two or more.

[0076] In the polysilsesquioxane particles (B), the T 3 The number of Si atoms included in the structure, the T 3 Structure, T 2 Structure, Q 2 Structure, Q 3 Structure, and the aforementioned Q 4 The ratio of the total number of Si atoms contained in each structure [T 3 / (T 3 +T 2 +Q 2 +Q 3 +Q 4 As mentioned above, the percentage of ) is 70% or more and less than 100%, preferably 80% or more and less than 100%, and more preferably 86% or more and less than 100%. In the polysilsesquioxane particles (B), the percentage of T 3 The more structural elements there are, the more desirable it is to obtain a resin composition that, upon curing, has a low dielectric constant and a low coefficient of thermal expansion. 3 The more structures there are, the fewer hydroxyl groups are contained in the polysilsesquioxane particles (B), and so on, resulting in a cured product with a low dielectric constant and a low coefficient of thermal expansion. Therefore, the ratio [T 3 / (T 3 +T 2 +Q 2 +Q 3 +Q 4)] is within the above range, the cured product of the resulting resin composition tends to have a low relative dielectric constant and a low coefficient of thermal expansion. However, in practice, the polysilsesquioxane particles (B) include the T 2 structure, the Q 2 structure, the Q 3 structure, and the Q 4 structure and other structures other than the T 3 structure in the molecule.

[0077] In the polysilsesquioxane particles (B), the T 2 structure, the Q 2 structure, and the Q 3 the ratio of the total number of Si atoms contained in each of the structures to the total number of Si atoms contained in each of the T 3 structure, the T 2 structure, the Q 2 structure, the Q 3 structure, and the Q 4 structure [(T 2 +Q 2 +Q 3 ) / (T 3 +T 2 +Q 2 +Q 3 +Q 4 )] is, as described above, more than 0% and 20% or less, preferably more than 0% and 15% or less, and more preferably more than 0% and 10% or less. In the polysilsesquioxane particles (B), the T 2 structure, the Q 2 structure, and the Q 3 the smaller the number of these structures, the relatively larger the number of the T 3 structures, and when cured, a resin composition that gives a cured product having a low relative dielectric constant and a low coefficient of thermal expansion can be obtained, which is preferable. This is for the same reason as described above, that is, the greater the number of the T 3 structures, the smaller the number of hydroxyl groups contained in the polysilsesquioxane particles (B), which is considered to result in a cured product having a low relative dielectric constant and a low coefficient of thermal expansion. Therefore, the ratio [(T 2 +Q 2 +Q 3 ) / (T 3 +T2 +Q 2 +Q 3 +Q 4 If the above range is present, the resulting cured resin composition tends to have a low dielectric constant and a low coefficient of thermal expansion.

[0078] The ratio [(T 3 / (T 3 +T 2 +Q 2 +Q 3 +Q 4 ), and the ratio [(T 2 +Q 2 +Q 3 ) / (T 3 +T 2 +Q 2 +Q 3 +Q 4 The measurement method for ) is not particularly limited as long as these ratios can be determined. For example, the T 3 Structure, T 2 Structure, Q 2 Structure, Q 3 Structure, and the aforementioned Q 4 The ratio of Si atoms contained in each part of the structure is T 3 structure, T 2 structure, Q 2 structure, Q 3 Structure, and Q 4 One possible method is to calculate it using a method that can determine the ratio of each structure to the total number of Si atoms contained in each structure, and then calculate it from the obtained ratios. That is, T 3 / (T 3 +T 2 +Q 2 +Q 3 +Q 4 ), T 2 / (T 3 +T 2 +Q 2 +Q 3 +Q 4 ), Q 2 / (T 3 +T 2 +Q 2 +Q 3 +Q 4 ), Q 3 / (T 3 +T2 +Q 2 +Q 3 +Q 4 ), and Q 4 / (T 3 +T 2 +Q 2 +Q 3 +Q 4 Examples include methods that use measurement methods to determine each of the following and then calculate the ratio from the obtained values. Specifically, the following measurement methods are examples.

[0079] First, solids using the dipolar decoupling (DD) method. 29 The silica spectrum is obtained by Si-NMR measurement. 29 In the Si-NMR spectrum, the T 3 Structure, T 2 Structure, Q 2 Structure, Q 3 Structure, and the aforementioned Q 4 The spectrum is obtained as having peaks originating from the Si atoms contained in each part of the structure. 29 In the Si-NMR spectrum, some peaks may overlap. And the silica solid... 29 If the Si-NMR spectrum obtained is a spectrum with overlapping peaks, waveform separation is performed on this spectrum. By doing so, the solid silica can be determined. 29 Each peak in the Si-NMR spectrum is obtained. From the assignment of the obtained spectrum, it can be determined which structure each peak represents.

[0080] Then, the area of ​​each peak (integral area) is calculated from the obtained peaks. Note that the area of ​​each peak can be calculated, for example, as follows: The aforementioned T 3 The peak area of ​​the structure is as follows: 3 Area enclosed by peaks that indicate structure (for example, the T 3 The area enclosed by the peaks and baseline or X-axis that represent the structure is determined. The peak area of ​​other structures (the T 2Structure, Q 2 Structure, Q 3 Structure, and the aforementioned Q 4 The peak area of ​​each structure is also the T 3 It is determined in the same way as the peak area of ​​the structure. And the obtained T 3 Structure, T 2 Structure, Q 2 Structure, Q 3 Structure, and the aforementioned Q 4 The peak area of ​​each structure, ST 3 ST 2 SQ 2 SQ 3 , and SQ 4 The aforementioned ratios are calculated as follows:

[0081] For example, the T 3 The number of Si atoms included in the structure, the T 3 Structure, T 2 Structure, Q 2 Structure, Q 3 Structure, and the aforementioned Q 4 The ratio of the total number of Si atoms contained in each structure [T 3 / (T 3 +T 2 +Q 2 +Q 3 +Q 4 The above T is calculated as follows: 3 Peak area of ​​the structure (ST 3 ) to the aforementioned T 3 Structure, T 2 Structure, Q 2 Structure, Q 3 Structure, and the aforementioned Q 4 The sum of the peak areas of each structure (ST 3 +ST 2 +SQ 2 +SQ 3 +SQ 4 By dividing by ), the ratio [T 3 / (T 3 +T 2 +Q 2 +Q 3 +Q 4 )] is obtained. That is, the ratio [T 3 / (T3 +T 2 +Q 2 +Q 3 +Q 4 )] is ST 3 / (ST 3 +ST 2 +SQ 2 +SQ 3 +SQ 4 It can be calculated as ) × 100 (%).

[0082] Said T 2 Structure, Q 2 Structure, and the aforementioned Q 3 The total number of Si atoms contained in each of the structures, T 3 Structure, T 2 Structure, Q 2 Structure, Q 3 Structure, and the aforementioned Q 4 The ratio of the total number of Si atoms contained in each structure [(T 2 +Q 2 +Q 3 ) / (T 3 +T 2 +Q 2 +Q 3 +Q 4 The above T is calculated as follows: 2 Structure, Q 2 Structure, and the aforementioned Q 3 The sum of the peak areas of each structure (ST 2 +SQ 2 +SQ 3 ) to the aforementioned T 3 Structure, T 2 Structure, Q 2 Structure, Q 3 Structure, and the aforementioned Q 4 The sum of the peak areas of each structure (ST 3 +ST 2 +SQ 2 +SQ 3 +SQ 4 By dividing by ), the ratio [(T 2 +Q 2 +Q 3 ) / (T 3 +T 2 +Q 2 +Q 3+Q 4 )] is obtained. That is, the ratio [(T 2 +Q 2 +Q 3 ) / (T 3 +T 2 +Q 2 +Q 3 +Q 4 )] is (ST 2 +SQ 2 +SQ 3 ) / (ST 3 +ST 2 +SQ 2 +SQ 3 +SQ 4 It can be calculated as ) × 100 (%).

[0083] The structure of the polysilsesquioxane particles (B) is not particularly limited and includes, for example, cage structures such as complete cage structures and incomplete cage structures such as partially cracked cage structures, ladder structures, and random structures. The polysilsesquioxane particles (B) may contain one of these structures individually or in combination of two or more. Furthermore, it is preferable that the polysilsesquioxane particles (B) contain polysilsesquioxane with a random structure. Examples of the polysilsesquioxane particles (B) include polysilsesquioxane particles containing polysilsesquioxane with a random structure as the main component (e.g., more than 50% by mass) and polysilsesquioxane with other structures as a minor component (e.g., less than 50% by mass), and polysilsesquioxane particles consisting of polysilsesquioxane with a random structure.

[0084] The particle size of the polysilsesquioxane particles (B) is not particularly limited, but is preferably 0.01 to 10 μm, and more preferably 0.1 to 5 μm, in terms of volume-average particle size. If the particle size of the polysilsesquioxane particles (B) is within the above range, a resin composition is obtained that, upon curing, has a low dielectric constant and a low coefficient of thermal expansion. The volume-average particle size here can be calculated from the particle size distribution measured by known methods such as dynamic light scattering. For example, it can be measured by a particle size analyzer (Multisizer 3 manufactured by Beckman Coulter, Inc.).

[0085] The hydroxyl equivalent of the polysilsesquioxane particles (B) is not particularly limited, but is preferably 300 to 3000 g / eq, and more preferably 500 to 2500 g / eq. If the hydroxyl equivalent of the polysilsesquioxane particles (B) is within the above range, a resin composition is obtained in which the cured product has a low dielectric constant and a low coefficient of thermal expansion. The hydroxyl equivalent here can be determined, for example, from the product's specification value.

[0086] The polysilsesquioxane particles (B) may be surface-treated polysilsesquioxane particles or untreated polysilsesquioxane particles. Examples of surface treatments include treatment with a silane coupling agent.

[0087] The silane coupling agent is not particularly limited, and examples include silane coupling agents having at least one functional group selected from the group consisting of vinyl group, styryl group, methacryloyl group, acryloyl group, phenylamino group, isocyanurate group, ureido group, mercapto group, isocyanate group, epoxy group, and acid anhydride group. That is, this silane coupling agent has at least one of vinyl group, styryl group, methacryloyl group, acryloyl group, phenylamino group, isocyanurate group, ureido group, mercapto group, isocyanate group, epoxy group, and acid anhydride group as a reactive functional group, and further includes compounds having hydrolyzable groups such as methoxy group and ethoxy group.

[0088] Examples of silane coupling agents that have a vinyl group include vinyltriethoxysilane and vinyltrimethoxysilane. Examples of silane coupling agents that have a styryl group include p-styryltrimethoxysilane and p-styryltriethoxysilane. Examples of silane coupling agents that have a methacryloyl group include 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, and 3-methacryloxypropylethyldiethoxysilane. Examples of silane coupling agents that have an acryloyl group include 3-acryloxypropyltrimethoxysilane and 3-acryloxypropyltriethoxysilane. Examples of silane coupling agents having a phenylamino group include N-phenyl-3-aminopropyltrimethoxysilane and N-phenyl-3-aminopropyltriethoxysilane.

[0089] Examples of the polysilsesquioxane particles (B) include BQ1510-SB, BQ1510-SSB, and BQQ1510, all manufactured by TAT.

[0090] (Reactive compound (C)) The resin composition may contain a reactive compound (C) that reacts with the curable compound (A). Alternatively, the resin composition may not contain the reactive compound (C), but it is preferable that it contains the reactive compound (C).

[0091] The reactive compound (C) is not particularly limited as long as it is a reactive compound that reacts with the curable compound (A) to contribute to the curing of the resin composition. Here, the reactive compound (C) is a compound that reacts with the curable compound (A) to contribute to the curing of the resin composition, and is a different compound from the curable compound (A). Examples of the reactive compound (C) include polyphenylene ether compounds having a carbon-carbon unsaturated double bond in the molecule, epoxy compounds, methacrylate compounds, acrylate compounds, cyanate ester compounds, active ester compounds, allyl compounds, acenaphthylene compounds, and vinyl compounds.

[0092] The polyphenylene ether compound is not particularly limited as long as it is a polyphenylene ether compound having a carbon-carbon unsaturated double bond in its molecule. Examples of the polyphenylene ether compound include polyphenylene ether compounds having a carbon-carbon unsaturated double bond at its terminus, and more specifically, modified polyphenylene ether compounds that have been terminally modified with substituents having carbon-carbon unsaturated double bonds, and other polyphenylene ether compounds having substituents having carbon-carbon unsaturated double bonds at their molecular termini.

[0093] Examples of substituents having a carbon-carbon unsaturated double bond include the group represented by formula (14) and the group represented by formula (15) below. That is, examples of the polyphenylene ether compound include a polyphenylene ether compound having at least one selected from the group represented by formula (14) and the group represented by formula (15) below in its molecule.

[0094] [ka]

[0095] In formula (14), p represents a value between 0 and 10. Ar represents an arylene group. R3 to R5 are independent of each other; that is, R3 to R5 may be the same group or different groups. R3 to R5 represent a hydrogen atom or an alkyl group. In formula (14), when p is 0, it indicates that Ar is directly bonded to the polyphenylene ether.

[0096] The aforementioned arylene group is not particularly limited. Examples of such arylene groups include monocyclic aromatic groups such as phenylene groups, and polycyclic aromatic groups such as naphthalene rings. Furthermore, 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, alkynyl group, formyl group, alkylcarbonyl group, alkenylcarbonyl group, or alkynylcarbonyl group.

[0097] The alkyl group is not particularly limited, but for example, alkyl groups having 1 to 18 carbon atoms are preferred, and alkyl groups having 1 to 10 carbon atoms are more preferred. Specifically, examples include methyl groups, ethyl groups, propyl groups, hexyl groups, and decyl groups.

[0098] [ka]

[0099] In formula (15), R6 represents a hydrogen atom or an alkyl group. The alkyl group is not particularly limited, but for example, alkyl groups having 1 to 18 carbon atoms are preferred, and alkyl groups having 1 to 10 carbon atoms are more preferred. Specifically, examples include methyl groups, ethyl groups, propyl groups, hexyl groups, and decyl groups.

[0100] Examples of the group represented by formula (14) include the vinylbenzyl group (ethenylbenzyl group) represented by formula (16) below. Examples of the group represented by formula (15) include the acryloyl group and the methacryloyl group.

[0101] [ka]

[0102] More specifically, examples of the substituents include vinyl benzyl groups (ethenyl benzyl groups) such as o-ethenylbenzyl groups, m-ethenylbenzyl groups, and p-ethenylbenzyl groups, vinylphenyl groups, acryloyl groups, and methacryloyl groups. The polyphenylene ether compound may have one of the substituents or two or more. For example, the polyphenylene ether compound may have any of the o-ethenylbenzyl groups, m-ethenylbenzyl groups, and p-ethenylbenzyl groups, or it may have two or three of these.

[0103] The polyphenylene ether compound has a polyphenylene ether chain in its molecule, and preferably has a repeating unit represented by the following formula (17) in its molecule.

[0104] [ka]

[0105] In equation (17), t represents a range of 1 to 50. Also, R7 to R 10 These are independent of each other. That is, R7~R 10 These may be the same group or different groups. Also, R7~R 10 This represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, a formyl group, an alkylcarbonyl group, an alkenylcarbonyl group, or an alkynylcarbonyl group. Among these, hydrogen atoms and alkyl groups are preferred.

[0106] R7~R 10 Specifically, the functional groups mentioned include the following:

[0107] The alkyl group is not particularly limited, but for example, alkyl groups having 1 to 18 carbon atoms are preferred, and alkyl groups having 1 to 10 carbon atoms are more preferred. Specifically, examples include methyl groups, ethyl groups, propyl groups, hexyl groups, and decyl groups.

[0108] The alkenyl group is not particularly limited, but for example, an alkenyl group having 2 to 18 carbon atoms is preferred, and an alkenyl group having 2 to 10 carbon atoms is more preferred. Specifically, examples include vinyl groups, allyl groups, and 3-butenyl groups.

[0109] The alkynyl group is not particularly limited, but for example, an alkynyl group having 2 to 18 carbon atoms is preferred, and an alkynyl group having 2 to 10 carbon atoms is more preferred. Specifically, examples include the ethynyl group and the propa-2-in-1-yl group (propargyl group).

[0110] The alkylcarbonyl group is not particularly limited as long as it is a carbonyl group substituted with an alkyl group, but for example, alkylcarbonyl groups having 2 to 18 carbon atoms are preferred, and alkylcarbonyl groups having 2 to 10 carbon atoms are more preferred. Specifically, examples include acetyl group, propionyl group, butyryl group, isobutyryl group, pivaloyl group, hexanoyl group, octanoyl group, and cyclohexylcarbonyl group.

[0111] The alkenylcarbonyl group is not particularly limited as long as it is a carbonyl group substituted with an alkenyl group, but for example, an alkenylcarbonyl group having 3 to 18 carbon atoms is preferred, and an alkenylcarbonyl group having 3 to 10 carbon atoms is more preferred. Specifically, examples include acryloyl groups, methacryloyl groups, and crotonoyl groups.

[0112] The alkynylcarbonyl group is not particularly limited as long as it is a carbonyl group substituted with an alkynyl group, but for example, an alkynylcarbonyl group having 3 to 18 carbon atoms is preferred, and an alkynylcarbonyl group having 3 to 10 carbon atoms is more preferred. Specifically, for example, a propioloyl group can be mentioned.

[0113] The weight-average molecular weight (Mw) and number-average molecular weight (Mn) of the polyphenylene ether compound are not particularly limited, but are preferably 500 to 5000, more preferably 800 to 4000, and even more preferably 1000 to 3000. Here, the weight-average molecular weight and number-average molecular weight can be measured by a general molecular weight measurement method, specifically values ​​measured using gel permeation chromatography (GPC). Furthermore, if the polyphenylene ether compound has repeating units represented by formula (17) in its molecule, it is preferable that t is a value such that the weight-average molecular weight and number-average molecular weight of the polyphenylene ether compound fall within this range. Specifically, t is preferably 1 to 50.

[0114] When the weight-average molecular weight and number-average molecular weight of the polyphenylene ether compound are within the above range, it possesses the excellent low dielectric properties of polyphenylene ether, resulting in a cured product that is not only superior in heat resistance but also in moldability. This is thought to be due to the following: In ordinary polyphenylene ethers, when the weight-average molecular weight and number-average molecular weight are within the above range, the molecular weight is relatively low, so the heat resistance tends to decrease. In this respect, since the polyphenylene ether compound has one or more unsaturated double bonds at its terminals, it is thought that the curing reaction proceeds to obtain a cured product with sufficiently high heat resistance. Furthermore, when the weight-average molecular weight and number-average molecular weight of the polyphenylene ether compound are within the above range, the molecular weight is relatively low, so it is thought to have excellent moldability. Therefore, it is thought that such a polyphenylene ether compound can be obtained that is not only superior in heat resistance but also in moldability.

[0115] The average number of said substituents at the molecular terminals per molecule of the polyphenylene ether compound (the number of terminal functional groups) in the above polyphenylene ether compound is not particularly limited. Specifically, it is preferably 1 to 5, more preferably 1 to 3, and still more preferably 1.5 to 3. If the number of terminal functional groups is too low, it tends to be difficult to obtain a cured product with sufficient heat resistance. If the number of terminal functional groups is too high, the reactivity becomes excessively high, which may cause problems such as reduced storage stability of the resin composition or decreased fluidity of the resin composition. That is, when such a polyphenylene ether compound is used, insufficient fluidity may cause molding defects such as void generation during multilayer molding, leading to the problem of moldability that makes it difficult to obtain a highly reliable printed wiring board.

[0116] The number of terminal functional groups of the polyphenylene ether compound may be a numerical value representing the average number of the above substituents per molecule of all polyphenylene ether compounds in 1 mole of the polyphenylene ether compound. The number of terminal functional groups can be measured, for example, by measuring the number of hydroxyl groups remaining in the obtained polyphenylene ether compound, and calculating the decrease from the number of hydroxyl groups of the polyphenylene ether before introducing the substituents (before modification). The decrease from the number of hydroxyl groups of the polyphenylene ether before modification corresponds to the number of terminal functional groups. The method for measuring the number of hydroxyl groups remaining in the polyphenylene ether compound can be carried out by adding a quaternary ammonium salt that associates with hydroxyl groups (tetraethylammonium hydroxide) to a solution of the polyphenylene ether compound, and measuring the UV absorbance of the mixed solution.

[0117] The intrinsic viscosity of the polyphenylene ether compound is not particularly limited. Specifically, it may be 0.03 to 0.12 dl / g, preferably 0.04 to 0.11 dl / g, and more preferably 0.06 to 0.095 dl / g. If the intrinsic viscosity is too low, the molecular weight tends to be low, and low dielectric properties such as low relative dielectric constant and low dielectric loss tangent tend to be difficult to obtain. If the intrinsic viscosity is too high, the viscosity will be high, sufficient fluidity cannot be obtained, and the moldability of the cured product tends to decrease. Therefore, when the intrinsic viscosity of the polyphenylene ether compound falls within the above range, excellent heat resistance and moldability of the cured product can be achieved.

[0118] Note that the intrinsic viscosity herein is an intrinsic viscosity measured in methylene chloride at 25°C. More specifically, it is, for example, a value obtained by measuring a 0.18 g / 45 ml methylene chloride solution (liquid temperature: 25°C) with a viscometer. Examples of such a viscometer include AVS500 Visco System manufactured by Schott.

[0119] Examples of the polyphenylene ether compound include a polyphenylene ether compound represented by the following formula (18) and a polyphenylene ether compound represented by the following formula (19). As the polyphenylene ether compound, these polyphenylene ether compounds may be used alone, or these two types of polyphenylene ether compounds may be used in combination.

[0120]

Chemical Formula

[0121]

Chemical Formula

[0122] In formula (18) and formula (19), R 11 ~R 18 and R 19 ~R 26 are each independent. That is, R 11~R 18 R 19 ~R 26 These may be the same group or different groups. Also, R 11 ~R 18 R 19 ~R 26 X1 represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, a formyl group, an alkylcarbonyl group, an alkenylcarbonyl group, or an alkynylcarbonyl group. X1 and X2 are independent of each other. That is, X1 and X2 may be the same group or different groups. X1 and X2 represent substituents having a carbon-carbon unsaturated double bond. A and B represent repeating units represented by the following formulas (20) and (21), respectively. In formula (19), Y represents a linear, branched, or cyclic hydrocarbon having 20 or fewer carbon atoms.

[0123] [ka]

[0124] [ka]

[0125] In equations (20) and (21), m and n represent values ​​from 0 to 20, respectively. 27 ~R 30 R 31 ~R 34 These are independent of each other. That is, R 27 ~R 30 R 31 ~R 34 These may be the same group or different groups. Also, R 27 ~R 30 R 31 ~R 34 This represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, a formyl group, an alkylcarbonyl group, an alkenylcarbonyl group, or an alkynylcarbonyl group.

[0126] The polyphenylene ether compound represented by formula (18) and the polyphenylene ether compound represented by formula (19) are not particularly limited as long as they satisfy the above configuration. Specifically, in formulas (18) and (19), R 11 ~R 18 R 19 ~R 26 As mentioned above, they are independent of each other. That is, R 11 ~R 18 R 19 ~R 26 These may be the same group or different groups. Also, R 11 ~R 18 R 19 ~R 26 This represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, a formyl group, an alkylcarbonyl group, an alkenylcarbonyl group, or an alkynylcarbonyl group. Among these, hydrogen atoms and alkyl groups are preferred.

[0127] In equations (20) and (21), it is preferable that m and n represent values ​​between 0 and 20, as described above. Furthermore, it is preferable that m and n represent values ​​such that the sum of m and n is between 1 and 30. Therefore, it is more preferable that m represents values ​​between 0 and 20, n represents values ​​between 0 and 20, and the sum of m and n is between 1 and 30. Also, R 27 ~R 30 R 31 ~R 34 These are independent of each other. That is, R 27 ~R 30 R 31 ~R 34 These may be the same group or different groups. Also, R 27 ~R 30 R 31 ~R 34 This represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, a formyl group, an alkylcarbonyl group, an alkenylcarbonyl group, or an alkynylcarbonyl group. Among these, hydrogen atoms and alkyl groups are preferred.

[0128] R11 ~R 34 is the same as R7 to R in the above formula (17) 10 .

[0129] In the above formula (19), Y is, as described above, a linear, branched or cyclic hydrocarbon having 20 or less carbon atoms. Examples of Y include groups represented by the following formula (22).

[0130]

Chemical Formula

[0131] In the above formula (22), R 35 and R 36 each independently represent a hydrogen atom or an alkyl group. Examples of the alkyl group include a methyl group. Examples of the group represented by formula (22) include a methylene group, a methylmethylene group, and a dimethylmethylene group. Among these, a dimethylmethylene group is preferable.

[0132] In the above formula (18) and the above formula (19), X1 and X2 are each independently a substituent having a carbon-carbon double bond. In the polyphenylene ether compound represented by formula (18) and the polyphenylene ether compound represented by formula (19), X1 and X2 may be the same group or different groups.

[0133] More specific examples of the polyphenylene ether compound represented by the above formula (18) include polyphenylene ether compounds represented by the following formula (23).

[0134]

Chemical Formula

[0135] More specific examples of polyphenylene ether compounds represented by formula (19) include, for example, the polyphenylene ether compound represented by formula (24) below, and the polyphenylene ether compound represented by formula (25) below.

[0136] [ka]

[0137] [ka]

[0138] In equations (23) to (25) above, m and n are the same as m and n in equations (20) and (21) above. Also, in equations (23) and (24) above, R3 to R5, p and Ar are the same as R3 to R5, p and Ar in equation (14) above. Also, in equations (24) and (25) above, Y is the same as Y in equation (12) above. Also, in equation (25) above, R6 is the same as R6 in equation (15) above.

[0139] The method for synthesizing the polyphenylene ether compound used in this embodiment is not particularly limited, as long as it can synthesize a polyphenylene ether compound having a carbon-carbon unsaturated double bond in its molecule. Specifically, this method includes reacting a polyphenylene ether with a compound in which a substituent having a carbon-carbon unsaturated double bond and a halogen atom are bonded.

[0140] Examples of compounds in which a substituent having a carbon-carbon unsaturated double bond is bonded to a halogen atom include compounds in which a substituent represented by formulas (14) to (16) is bonded to a halogen atom. Specifically, examples of halogen atoms include chlorine atoms, bromine atoms, iodine atoms, and fluorine atoms, with chlorine atoms being preferred among these. More specifically, examples of compounds in which a substituent having a carbon-carbon unsaturated double bond is bonded to a halogen atom include o-chloromethylstyrene, p-chloromethylstyrene, and m-chloromethylstyrene. The compounds in which a substituent having a carbon-carbon unsaturated double bond is bonded to a halogen atom may be used alone or in combination of two or more. For example, o-chloromethylstyrene, p-chloromethylstyrene, and m-chloromethylstyrene may be used alone or in combination of two or three.

[0141] The raw material, polyphenylene ether, is not particularly limited as long as it can ultimately synthesize the desired polyphenylene ether compound. Specifically, examples include polyphenylene ethers mainly composed of 2,6-dimethylphenol and at least one of a difunctional phenol and a trifunctional phenol, or poly(2,6-dimethyl-1,4-phenylene oxide). A difunctional phenol is a phenol compound having two phenolic hydroxyl groups in its molecule, such as tetramethylbisphenol A. A trifunctional phenol is a phenol compound having three phenolic hydroxyl groups in its molecule.

[0142] The method for synthesizing the polyphenylene ether compound is as described above. Specifically, the polyphenylene ether described above and the compound in which a substituent having a carbon-carbon unsaturated double bond and a halogen atom are bonded are dissolved in a solvent and stirred. By doing so, the polyphenylene ether and the compound in which the substituent having a carbon-carbon unsaturated double bond and a halogen atom are bonded react to obtain the polyphenylene ether compound used in this embodiment.

[0143] It is preferable to carry out the above reaction in the presence of an alkali metal hydroxide. This is thought to allow the reaction to proceed favorably. This is because the alkali metal hydroxide functions as a dehalogenating agent, specifically a dehydrochlorinating agent. That is, the alkali metal hydroxide removes hydrogen halides from the phenol group of the polyphenylene ether and from the compound in which the substituent having a carbon-carbon unsaturated double bond and the halogen atom are bonded. In this way, the substituent having a carbon-carbon unsaturated double bond is thought to bond to the oxygen atom of the phenol group of the polyphenylene ether in place of the hydrogen atom of the phenol group.

[0144] The alkali metal hydroxide is not particularly limited as long as it can act as a dehalogenating agent, but examples include sodium hydroxide. Furthermore, alkali metal hydroxides are usually used in aqueous solution form, specifically as an aqueous solution of sodium hydroxide.

[0145] The reaction conditions, such as reaction time and reaction temperature, vary depending on the compound in which a substituent having a carbon-carbon unsaturated double bond is bonded to a halogen atom, and are not particularly limited as long as the above-mentioned conditions allow the reaction to proceed favorably. Specifically, the reaction temperature is preferably room temperature to 100°C, and more preferably 30 to 100°C. The reaction time is preferably 0.5 to 20 hours, and more preferably 0.5 to 10 hours.

[0146] The solvent used in the reaction is not particularly limited, as long as it can dissolve the polyphenylene ether and the compound in which the substituent having a carbon-carbon unsaturated double bond and a halogen atom are bonded, and does not inhibit the reaction between the polyphenylene ether and the compound in which the substituent having a carbon-carbon unsaturated double bond and a halogen atom are bonded. Specifically, examples include toluene.

[0147] The above reaction is preferably carried out in the presence of not only an alkali metal hydroxide but also a phase-transfer catalyst. In other words, the above reaction is preferably carried out in the presence of both an alkali metal hydroxide and a phase-transfer catalyst. It is believed that the above reaction proceeds more favorably by doing so. This is thought to be because the phase-transfer catalyst has the function of incorporating alkali metal hydroxides, is soluble in both the polar solvent phase such as water and the non-polar solvent phase such as an organic solvent, and is a catalyst that can move between these phases. Specifically, when an aqueous sodium hydroxide solution is used as the alkali metal hydroxide and an organic solvent such as toluene, which is immiscible with water, is used as the solvent, even if the aqueous sodium hydroxide solution is added dropwise to the solvent being used in the reaction, the solvent and the aqueous sodium hydroxide solution will separate, and it is thought that the sodium hydroxide will not easily migrate into the solvent. In that case, it is thought that the aqueous sodium hydroxide solution added as the alkali metal hydroxide will not contribute much to promoting the reaction. In contrast, when the reaction is carried out in the presence of an alkali metal hydroxide and a phase-transfer catalyst, the alkali metal hydroxide is incorporated into the phase-transfer catalyst and migrates to the solvent, and the aqueous sodium hydroxide solution is thought to contribute more readily to promoting the reaction. For this reason, the above reaction is thought to proceed more favorably when carried out in the presence of an alkali metal hydroxide and a phase-transfer catalyst.

[0148] The phase transfer catalyst is not particularly limited, but examples include quaternary ammonium salts such as tetra-n-butylammonium bromide.

[0149] The polyphenylene ether compound contained in the resin composition preferably includes the polyphenylene ether compound obtained as described above.

[0150] The epoxy compound is a compound having an epoxy group in its molecule, and specifically includes bisphenol-type epoxy compounds such as bisphenol A-type epoxy compounds, phenol novolac-type epoxy compounds, cresol novolac-type epoxy compounds, dicyclopentadiene-type epoxy compounds, bisphenol A novolac-type epoxy compounds, biphenyl aralkyl-type epoxy compounds, and naphthalene ring-containing epoxy compounds. The epoxy compound also includes epoxy resins, which are polymers of each of the epoxy compounds.

[0151] 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).

[0152] 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.

[0153] The aforementioned cyanate ester compounds are compounds having a cyanate group in their molecule, and examples include 2,2-bis(4-cyanatephenyl)propane, bis(3,5-dimethyl-4-cyanatephenyl)methane, and 2,2-bis(4-cyanatephenyl)ethane.

[0154] 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.

[0155] 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).

[0156] The aforementioned acenaphthylene compounds are compounds having an acenaphthylene structure in their molecules, and examples include acenaphthylene, alkylacenaphthylenes, halogenated acenaphthylenes, and phenylacenaphthylenes. Examples of the alkylacenaphthylenes include 1-methylacenaphthylene, 3-methylacenaphthylene, 4-methylacenaphthylene, 5-methylacenaphthylene, 1-ethylacenaphthylene, 3-ethylacenaphthylene, 4-ethylacenaphthylene, and 5-ethylacenaphthylene. Examples of the halogenated acenaphthylenes include 1-chloroacenaphthylene, 3-chloroacenaphthylene, 4-chloroacenaphthylene, 5-chloroacenaphthylene, 1-bromoacenaphthylene, 3-bromoacenaphthylene, 4-bromoacenaphthylene, and 5-bromoacenaphthylene. Examples of the phenylacenaphthylenes include 1-phenylacenaphthylene, 3-phenylacenaphthylene, 4-phenylacenaphthylene, and 5-phenylacenaphthylene. The acenaphthylene compound may be a monofunctional acenaphthylene compound having one acenaphthylene structure in the molecule, as described above, or a polyfunctional acenaphthylene compound having two or more acenaphthylene structures in the molecule.

[0157] 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.

[0158] Among these, the reactive compound (C) is preferably the polyphenylene ether compound (a polyphenylene ether compound having a carbon-carbon unsaturated double bond in its molecule) and triallyl isocyanurate compounds such as triallyl isocyanurate (TAIC). Furthermore, the reactive compound (C) may be used alone or in combination of two or more types.

[0159] The weight-average molecular weight of the reactive compound is not particularly limited, but is preferably 100 to 5000, more preferably 100 to 4000, and even more preferably 100 to 3000. If the weight-average molecular weight of the reactive compound is too low, the reactive compound may easily volatilize from the resin composition's compounding system. If the weight-average molecular weight of the reactive compound is too high, the viscosity of the varnish of the resin composition, or the melt viscosity when the resin composition is in the B stage, may become too high, potentially leading to poor moldability and poor appearance after molding. Therefore, when the weight-average molecular weight of the reactive compound is within this range, a resin composition with superior heat resistance and moldability of the cured product can be obtained. This is thought to be because the resin composition can be cured suitably. Here, the weight-average molecular weight can be any value measured by a general molecular weight measurement method, specifically, values ​​measured using gel permeation chromatography (GPC), etc.

[0160] The number of functional groups per molecule of the reactive compound that contribute to the reaction during curing of the resin composition varies depending on the weight-average molecular weight of the reactive compound, but is preferably 1 to 20, and more preferably 2 to 18. If the number of functional groups is too small, it tends to be difficult to obtain a cured product with sufficient heat resistance. On the other hand, if the number of functional groups is too large, the reactivity becomes too high, which may cause problems such as a decrease in the shelf life of the resin composition or a decrease in the fluidity of the resin composition.

[0161] (Styrene-based elastomer (D)) The resin composition may optionally contain a styrene-based elastomer (D) as long as it does not impair the effects of the present invention. The resin composition may not contain the styrene-based elastomer (D), but it is preferable that it contains the styrene-based elastomer (D).

[0162] The styrene-based elastomer (D) is not particularly limited, and examples include elastomers containing copolymers obtained by polymerizing monomers including styrene monomers. Furthermore, the styrene-based elastomer (D) is a compound different from the hydrocarbon compound (A3). Examples of the styrene-based elastomer (D) include elastomers containing copolymers obtained by copolymerizing one or more of the styrene monomers with one or more other monomers copolymerizable with the styrene monomers. The copolymer constituting the styrene-based elastomer (D) may be a random copolymer, a block copolymer, an alternating copolymer, or a graft copolymer, as long as it has a structure derived from the styrene monomer within its molecule. Among these, a block copolymer, i.e., a styrene-based block copolymer, is preferred as the copolymer constituting the styrene-based elastomer (D). The styrene-based block copolymer is not particularly limited, and examples include block copolymers obtained by polymerizing monomers including styrene monomers. In other words, the styrene-based block copolymer is a block copolymer having at least a structure (repeating unit) derived from the styrene-based monomer in its molecule. Examples of the styrene-based block copolymer include block copolymers obtained by copolymerizing one or more of the styrene-based monomers with one or more other monomers copolymerizable with the styrene-based monomers. As described above, the styrene-based block copolymer only needs to be a block copolymer having at least a structure (repeating unit) derived from the styrene-based monomer in its molecule, and examples include binary copolymers, ternary copolymers, and quaternary or more copolymers. The binary copolymer is a binary copolymer of a structure (repeating unit) derived from the styrene-based monomer and a structure (repeating unit) derived from the other copolymerizable monomer.Furthermore, examples of the ternary copolymer include a ternary copolymer of a structure (repeating unit) derived from the styrene monomer, a structure (repeating unit) derived from another copolymerizable monomer, and a ternary copolymer of a structure (repeating unit) derived from another copolymerizable monomer, a structure (repeating unit) derived from the styrene monomer, and a structure (repeating unit) derived from another copolymerizable monomer. The styrene copolymer may also be a hydrogenated styrene copolymer obtained by hydrogenating the styrene copolymer. Furthermore, the styrene copolymer may also be a hydrogenated styrene block copolymer obtained by hydrogenating the styrene block copolymer.

[0163] The styrene monomer is not particularly limited, but examples include styrene, styrene derivatives, styrene in which some of the hydrogen atoms of the benzene ring are substituted with alkyl groups, styrene in which some of the hydrogen atoms of the vinyl group are substituted with alkyl groups, vinyltoluene, α-methylstyrene, butylstyrene, dimethylstyrene, and isopropenyltoluene. The styrene monomer may be used individually or in combination of two or more. The other copolymerizable monomers are not particularly limited, but examples include olefins such as α-pinene, β-pinene, and dipentene, non-conjugated dienes such as 1,4-hexadiene and 3-methyl-1,4-hexadiene, and conjugated dienes such as 1,3-butadiene and 2-methyl-1,3-butadiene (isoprene). The other copolymerizable monomers may be used individually or in combination of two or more.

[0164] The styrene-based copolymer can be a wide range of conventionally known copolymers and is not particularly limited, but examples include copolymers (preferably block copolymers) having a structural unit represented by the following formula (26) (a structure derived from the styrene-based monomer) in the molecule.

[0165] [ka]

[0166] In formula (26), R 38 ~R 40 Each independently represents a hydrogen atom or an alkyl group, and R 41 This represents a group selected from the group consisting of a hydrogen atom, an alkyl group, an alkenyl group, and an isopropenyl group. The alkyl group is not particularly limited, but for example, an alkyl group having 1 to 18 carbon atoms is preferred, and an alkyl group having 1 to 10 carbon atoms is more preferred. Specifically, examples include a methyl group, an ethyl group, a propyl group, a hexyl group, and a decyl group. Furthermore, the alkenyl group is preferably an alkenyl group having 1 to 10 carbon atoms.

[0167] The styrene copolymer preferably contains at least one structural unit represented by formula (26), and may contain a combination of two or more different structural units. Furthermore, the styrene copolymer may contain a structure in which the structural unit represented by formula (26) is repeated.

[0168] In addition to the structural unit represented by formula (26), the styrene copolymer may also have at least one of the structural units represented by the following formulas (27) to (29) as a structural unit derived from another monomer copolymerizable with the styrene monomer. Furthermore, the structural unit derived from the other monomer copolymerizable with the styrene monomer may include structures in which each of the structural units represented by the following formulas (27) to (29) is repeated.

[0169] [ka]

[0170] [ka]

[0171] [ka]

[0172] In equations (27) to (29) above, R 42 ~R 59 Each of these independently represents a group selected from the group consisting of a hydrogen atom, an alkyl group, an alkenyl group, and an isopropenyl group. The alkyl group is not particularly limited, but for example, an alkyl group having 1 to 18 carbon atoms is preferred, and an alkyl group having 1 to 10 carbon atoms is more preferred. Specifically, examples include a methyl group, an ethyl group, a propyl group, a hexyl group, and a decyl group. Furthermore, the alkenyl group is preferably an alkenyl group having 1 to 10 carbon atoms.

[0173] The styrene copolymer preferably contains at least one structural unit represented by formulas (27) to (29), and may contain a combination of two or more different structural units. Furthermore, the styrene copolymer may contain a structure in which the structural units represented by formulas (27) to (29) are repeated.

[0174] More specifically, the structural units represented by formula (26) include the structural units represented by formulas (30) to (32) below. Furthermore, the structural units represented by formula (26) may also be structures in which the structural units represented by formulas (30) to (32) below are repeated. The structural units represented by formula (26) may be a single unit or a combination of two or more different units.

[0175] [ka]

[0176] [ka]

[0177] [ka]

[0178] More specifically, the structural units represented by formula (27) include the structural units represented by formulas (33) to (39) below. Furthermore, the structural units represented by formula (27) may also be structures in which the structural units represented by formulas (33) to (39) below are repeated. The structural units represented by formula (27) may be a single unit or a combination of two or more different units.

[0179] [ka]

[0180] [ka]

[0181] [ka]

[0182] [ka]

[0183] [ka]

[0184] [ka]

[0185] [ka]

[0186] More specifically, the structural units represented by formula (28) include the structural units represented by formulas (40) and (41) below. Furthermore, the structural units represented by formula (28) may also be structures in which the structural units represented by formulas (40) and (41) below are repeated. The structural units represented by formula (28) may be a single unit or a combination of two or more different units.

[0187] [ka]

[0188] [ka]

[0189] More specifically, the structural units represented by formula (29) include the structural units represented by formulas (42) and (43) below. Furthermore, the structural units represented by formula (29) may also be structures in which the structural units represented by formulas (42) and (43) below are repeated. The structural units represented by formula (29) may be a single unit or a combination of two or more different units.

[0190] [ka]

[0191] [ka]

[0192] Preferred examples of the styrene copolymer include copolymers obtained by copolymerizing one or more styrene monomers such as styrene, vinyltoluene, α-methylstyrene, isopropenyltoluene, divinylbenzene, and allylstyrene. More specifically, examples of the styrene copolymer include methylstyrene (ethylene / butylene) methylstyrene block copolymer, methylstyrene (ethylene-ethylene / propylene) methylstyrene block copolymer, styrene isoprene block copolymer, styrene isoprene styrene block copolymer, styrene (ethylene / butylene) styrene block copolymer, styrene (ethylene-ethylene / propylene) styrene block copolymer, styrene butadiene styrene block copolymer, styrene (butadiene / butylene) styrene block copolymer, and styrene isobutylene styrene block copolymer. Examples of the hydrogenated styrene copolymer include hydrogenated products of the styrene copolymer. More specifically, examples of the hydrogenated styrene-based copolymers include hydrogenated methylstyrene (ethylene / butylene) methylstyrene block copolymer, hydrogenated methylstyrene (ethylene-ethylene / propylene) methylstyrene block copolymer, hydrogenated styrene isoprene block copolymer, hydrogenated styrene isoprene styrene block copolymer, hydrogenated styrene (ethylene / butylene) styrene block copolymer, and hydrogenated styrene (ethylene-ethylene / propylene) styrene block copolymer.

[0193] The styrene copolymer may be one of the exemplified styrene copolymers used alone, or two or more may be used in combination.

[0194] In the styrene copolymer, when at least one of the structural units represented by formulas (30) to (32) is included, the mass fraction (i.e., the content of styrene-derived structural units) is preferably about 10 to 60% of the total polymer, and more preferably about 20 to 40%. This has the advantage of maintaining good compatibility with the radical polymerizable compound while also obtaining superior dielectric properties when the resin composition is cured.

[0195] The weight-average molecular weight of the styrene copolymer is preferably 10,000 to 200,000, and more preferably 50,000 to 180,000. If the molecular weight is too low, the glass transition temperature of the cured resin composition tends to decrease, and the heat resistance tends to decrease. If the molecular weight is too high, the viscosity of the resin composition when it is made into a varnish and the viscosity of the resin composition during heat molding tend to become too high. If the molecular weight is within the above range, there is an advantage in that it is possible to ensure appropriate resin fluidity in the resin composition or the semi-cured state (B stage) of the resin composition. The weight-average molecular weight can be measured by any general molecular weight measurement method, specifically, values ​​measured using gel permeation chromatography (GPC), etc.

[0196] The styrene-based elastomer (D) is preferably a styrene-based copolymer with a hardness of 20 to 100, and more preferably a styrene-based copolymer with a hardness of 30 to 80. It is believed that by including a styrene-based copolymer with a hardness within the above range, a resin composition can be obtained in which, upon curing, the dielectric properties such as relative permittivity are lower and the cured product has a lower coefficient of thermal expansion.

[0197] The hardness mentioned above may include, for example, durometer hardness, and more specifically, durometer hardness measured using a Type A durometer conforming to JIS K 6253.

[0198] As the styrene-based elastomer (D), commercially available products can be used, for example, Septon V9827, Septon V9461, Septon 1020, Septon 2002, Septon 2004F, Septon 2005, Septon 2006, Septon 2063, Septon 2104, Septon 4033, Septon 4044, Septon 4055, Septon 4077, manufactured by Kuraray Co., Ltd. Septon 4099, Septon 8004, Septon 8006, Septon 8007L, Septon HG252, Hybrar 5125, Hybrar 5127, Hybrar 7125F, and Hybrar 7311F, FTR2140 and FTR6125 from Mitsui Chemicals, Inc., and DYNARON 1320P, DYNARON 1321P, and DYNARON 2324P from JSR Corporation. DYNARON4600P, DYNARON6200P, DYNARON6201B, DYNARON8600P, DYNARON8300P, DYNARON8903P, and DYNARON9901P, and Asahi Kasei Corporation's ToughTec H1221, ToughTec H1062, ToughTec H1521, ToughTec H1051, ToughTec H1517, ToughTec H1043, You may also use ToughTec N504, ToughTec H1272, ToughTec M1943, ToughTec M1911, ToughTec M1913, ToughTec MP10, ToughTec P1083, ToughTec P1500, ToughTec P5051, and ToughTec P2000, as well as Kaneka Corporation's SIBSTAR series 062M, 062T, 072T, 073T, 102T, and 103T, etc.

[0199] (Inorganic filler (E)) The resin composition may optionally contain inorganic fillers (E) other than the polysilsesquioxane particles (B), as long as this does not impair the effects of the present invention. Even if the polysilsesquioxane particles (B) act as a filler, the resin composition may still contain inorganic fillers (E) other than the polysilsesquioxane particles (B).

[0200] The inorganic filler (E) is not particularly limited as long as it is an inorganic filler that can be used as an inorganic filler contained in the resin composition. Examples of the inorganic filler (E) include silica, alumina, titanium oxide, magnesium oxide and mica and other metal oxides, metal hydroxides such as magnesium hydroxide and aluminum hydroxide, talc, aluminum borate, barium sulfate, aluminum nitride, boron nitride, barium titanate, magnesium carbonate such as anhydrous magnesium carbonate, and calcium carbonate. Among these, silica, metal hydroxides such as magnesium hydroxide and aluminum hydroxide, aluminum oxide, boron nitride and barium titanate are preferred, and silica is more preferred. The silica is not particularly limited, and examples include crushed silica, spherical silica and silica particles, with spherical silica being preferred. That is, it is preferable to use the polysilsesquioxane particles (B) and silica in combination in the resin composition, and it is more preferable to use the polysilsesquioxane particles (B) and spherical silica in combination.

[0201] The inorganic filler (E) may be a surface-treated inorganic filler or an untreated inorganic filler. The surface treatment can be, for example, treatment with a silane coupling agent. The silane coupling agent is not particularly limited and can be, for example, a silane coupling agent similar to the one used for surface treatment of the polysilsesquioxane particles (B).

[0202] The average particle size of the inorganic filler (E) is not particularly limited, but is preferably 0.05 to 10 μm, and more preferably 0.1 to 8 μm. Here, the average particle size refers to the volume-average particle size. The volume-average particle size can be measured, for example, by laser diffraction.

[0203] (Content) The content of the polysilsesquioxane particles (B) is preferably 10 to 200 parts by mass, more preferably 30 to 150 parts by mass, and even more preferably 50 to 120 parts by mass, per 100 parts by mass of the resin component. That is, the content of the polysilsesquioxane particles (B) is preferably 10 to 200 parts by mass, more preferably 30 to 150 parts by mass, and even more preferably 50 to 120 parts by mass, per 100 parts by mass of the total of the curable compound (A), the reactive compound (C), and the styrene-based elastomer (D). More specifically, if the resin component includes the curable compound (A) and the reactive compound (C) but does not include the styrene-based elastomer (D), the content of the polysilsesquioxane particles (B) is preferably 10 to 200 parts by mass, more preferably 30 to 150 parts by mass, and even more preferably 50 to 120 parts by mass, based on 100 parts by mass of the total of the curable compound (A) and the reactive compound (C). Furthermore, if the resin component includes the curable compound (A) but does not include the reactive compound (C) and the styrene-based elastomer (D), the content of the polysilsesquioxane particles (B) is preferably 10 to 200 parts by mass, more preferably 30 to 150 parts by mass, and even more preferably 50 to 120 parts by mass, based on 100 parts by mass of the curable compound (A). Furthermore, when the resin component includes the curable compound (A), the reactive compound (C), and the styrene-based elastomer (D), the content of the polysilsesquioxane particles (B) is preferably within the above range, i.e., 10 to 200 parts by mass, more preferably 30 to 150 parts by mass, and even more preferably 50 to 120 parts by mass, per 100 parts by mass of the total of the curable compound (A), the reactive compound (C), and the styrene-based elastomer (D). When the content of the polysilsesquioxane particles (B) is within the above range, the effects achieved by including the polysilsesquioxane particles (B) can be fully exhibited, and a resin composition with a low dielectric constant and a low coefficient of thermal expansion can be more preferably obtained when cured.

[0204] The resin composition may contain the reactive compound (C) as described above. When the resin composition contains the reactive compound (C), the content of the reactive compound (C) is preferably 10 to 40 parts by mass per 100 parts by mass of the total of the curable compound (A) and the reactive compound (C). Furthermore, the content of the curable compound (A) is preferably 50 to 90 parts by mass per 100 parts by mass of the total of the curable compound (A) and the reactive compound (C).

[0205] The resin composition may contain the styrene-based elastomer (D) as described above. When the resin composition contains the styrene-based elastomer (D), the amount of the styrene-based elastomer (D) is preferably 10 to 60 parts by mass per 100 parts by mass of the resin component, i.e., 100 parts by mass of the total of the curable compound (A), the reactive compound (C), and the styrene-based elastomer (D).

[0206] The resin composition may contain the inorganic filler (E) as described above. When the resin composition contains the inorganic filler (E), that is, when the polysilsesquioxane particles (B) and the inorganic filler (E) are used in combination, the amount of the inorganic filler (E) is preferably 10 to 50 parts by mass per 100 parts by mass of the total of the polysilsesquioxane particles (B) and the inorganic filler (E).

[0207] (Other ingredients) The resin composition may contain components other than the curable compound (A) and the polysilsesquioxane particles (B) (other components) to the extent that they do not impair the effects of the present invention. The resin composition may contain, as described above, the reactive compound (C), the styrene-based elastomer (D), and the inorganic filler (E) as the other components. Examples of other components other than the reactive compound (C), the styrene-based elastomer (D), and the inorganic filler (E) include, for example, flame retardants, reaction initiators, reaction accelerators, catalysts, polymerization retarders, polymerization inhibitors, dispersants, leveling agents, coupling agents, defoamers, antioxidants, heat stabilizers, antistatic agents, ultraviolet absorbers, dyes and pigments, and lubricants.

[0208] As described above, the resin composition according to this embodiment may contain a flame retardant. By including a flame retardant, the flame retardancy of the cured resin composition can be enhanced. The flame retardant is not particularly limited. Specifically, in fields where halogen-based flame retardants such as brominated flame retardants are used, for example, ethylene dipentabromobenzene, ethylene bistetrabromoimide, decabromodiphenyl oxide, tetradecabromodiphenoxybenzene, and bromostyrene compounds that react with the polymerizable compound are preferred, each having a melting point of 300°C or higher. It is believed that by using a halogen-based flame retardant, the desorption of halogens at high temperatures can be suppressed, thereby suppressing a decrease in heat resistance. In addition, in fields where halogen-free is required, a phosphorus-containing flame retardant (phosphorus-based flame retardant) may be used. The phosphorus-based flame retardant is not particularly limited, but examples include phosphate ester-based flame retardants, phosphazene-based flame retardants, bis-diphenylphosphine oxide-based flame retardants, and phosphinate-based flame retardants. 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 xylylene bis-diphenylphosphine oxide. Specific examples of phosphinate-based flame retardants include, for example, phosphinate metal salts of aluminum dialkylphosphinate. The flame retardants described above may be used individually or in combination of two or more.

[0209] As described above, the resin composition according to this embodiment may contain a reaction initiator. The reaction initiator is not particularly limited as long as it can promote the curing reaction of the resin composition, and examples include peroxides and organic azo compounds. Examples of peroxides include α,α'-bis(t-butylperoxy-m-isopropyl)benzene, 2,5-dimethyl-2,5-di(t-butylperoxy)-3-hexine, and benzoyl peroxide. Examples of organic azo compounds include azobisisobutyronitrile. In addition, metal carboxylate salts can be used in combination as needed. By doing so, the curing reaction can be further promoted. Among these, α,α'-bis(t-butylperoxy-m-isopropyl)benzene is preferably used. Because α,α'-bis(t-butylperoxy-m-isopropyl)benzene has a relatively high reaction initiation temperature, it can suppress the promotion of the curing reaction at times when curing is not necessary, such as during prepreg drying, and can suppress a decrease in the shelf life of the resin composition. Furthermore, α,α'-bis(t-butylperoxy-m-isopropyl)benzene has low volatility, so it does not volatilize during prepreg drying or storage, resulting in good stability. Also, the reaction initiator may be used alone or in combination of two or more.

[0210] As described above, the resin composition according to this embodiment may contain a silane coupling agent. The silane coupling agent may be contained in the resin composition, or it may be contained in the inorganic filler contained in the resin composition as a silane coupling agent that has been pre-surface-treated. Among these, it is preferable that the silane coupling agent be contained in the inorganic filler as a silane coupling agent that has been pre-surface-treated, and it is even more preferable that the resin composition also contains the silane coupling agent in this manner. In the case of a prepreg, the prepreg may contain a silane coupling agent that has been pre-surface-treated in the fibrous substrate. Examples of the silane coupling agent include those similar to the silane coupling agent used when surface-treating the inorganic filler as described above.

[0211] The resin composition according to this embodiment is a resin composition that yields a cured product with a low dielectric constant and a low coefficient of thermal expansion.

[0212] (Application) The aforementioned resin composition is used in the manufacture of prepregs, as will be described later. Furthermore, the resin composition is used in forming resin layers in resin-coated metal foils and resin-coated films, and in forming insulating layers in metal-clad laminates and wiring boards.

[0213] (Manufacturing method) The method for producing the resin composition is not particularly limited, and examples include mixing the curable compound (A) and the polysilsesquioxane particles (B) in predetermined amounts. Furthermore, when obtaining a varnish-like composition containing an organic solvent, the method described later may be used.

[0214] By using the resin composition according to this embodiment, prepregs, metal-clad laminates, wiring boards, resin-coated metal foils, and resin-coated films can be obtained as follows.

[0215] [Prepreg] Figure 1 is a schematic cross-sectional view showing an example of prepreg 1 according to an embodiment of the present invention.

[0216] 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. This prepreg 1 comprises the resin composition or a semi-cured product 2 of the resin composition and a fibrous base material 3 present in the resin composition or the semi-cured product 2 of the resin composition.

[0217] In this embodiment, a 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, and then curing begins, causing the viscosity to gradually increase. In such a case, a semi-cured state would be the state between the time the viscosity begins to increase and before it is completely cured.

[0218] 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. 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.

[0219] When manufacturing the prepreg, the resin composition 2 is often prepared in a varnish-like form for impregnation into the fibrous substrate 3, which is the base material for forming the prepreg. That is, the resin composition 2 is usually a resin varnish prepared in a varnish-like form. Such a varnish-like resin composition (resin varnish) is prepared, for example, as follows.

[0220] First, each component that can be dissolved in an organic solvent is added to the organic solvent and dissolved. Heating may be used as needed during this process. Then, components that cannot be dissolved in the organic solvent are added as needed, 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 polyphenylene ether compound and the reactive compound, etc., and does not inhibit the curing reaction. Specifically, examples include toluene and methyl ethyl ketone (MEK).

[0221] 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. When glass cloth is used, a laminate with excellent mechanical strength can be obtained, and flattened glass cloth is particularly preferred. Specific examples of the flattening process include a method in which the glass cloth is continuously pressed with a press roll at an appropriate pressure to flatten the yarn. The thickness of the fibrous substrate commonly used is, for example, 0.01 mm to 0.3 mm. The glass fibers constituting the glass cloth are not particularly limited, but examples include Q glass, NE glass, E glass, S glass, T glass, L glass, and L2 glass. The surface of the fibrous substrate may also be surface-treated with a silane coupling agent. The silane coupling agent is not particularly limited, but examples include a silane coupling agent having at least one group selected from the group consisting of vinyl group, acryloyl group, methacryloyl group, styryl group, amino group, and epoxy group in its molecule.

[0222] The method for manufacturing the prepreg is not particularly limited as long as it can produce the prepreg. Specifically, when manufacturing the prepreg, the resin composition according to this embodiment is often prepared in a varnish-like state as described above and used as a resin varnish.

[0223] A specific method for manufacturing the prepreg 1 is to impregnate a fibrous substrate 3 with the resin composition 2, for example, a resin composition 2 prepared in the form of a varnish, and then dry it. The resin composition 2 is impregnated into the fibrous substrate 3 by immersion, coating, etc. It is also possible to repeat the impregnation process multiple times as needed. Furthermore, by repeating the impregnation process using multiple resin compositions with different compositions and concentrations, it is possible to adjust the final composition and amount of impregnation to the desired level.

[0224] The fibrous substrate 3 impregnated with the resin composition (resin varnish) 2 is heated under desired heating conditions, for example, at 40°C to 180°C for 1 minute to 10 minutes. Heating yields a prepreg 1 in either a pre-cured state (Stage A) or a semi-cured state (Stage B). Heating can also cause organic solvents to volatilize from the resin varnish, reducing or removing them.

[0225] The resin composition according to this embodiment is a resin composition that yields a cured product with a low dielectric constant and a low coefficient of thermal expansion. That is, when the resin composition is cured, it becomes a cured product with a low dielectric constant and a low coefficient of thermal expansion. Therefore, a prepreg comprising this resin composition or a semi-cured product of this resin composition is a prepreg that yields a cured product with a low dielectric constant and a low coefficient of thermal expansion. Furthermore, this prepreg can suitably manufacture a wiring board having an insulating layer containing a cured product with a low dielectric constant and a low coefficient of thermal expansion.

[0226] [Metal-clad laminate] Figure 2 is a schematic cross-sectional view showing an example of a metal-clad laminate 11 according to an embodiment of the present invention.

[0227] As shown in Figure 2, the metal-clad laminate 11 according to this embodiment has an insulating layer 12 containing a cured product of the resin composition and a metal foil 13 provided 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 Figure 1 and a metal foil 13 laminated together with the insulating layer 12. The insulating layer 12 may be made of a cured product of the resin composition or a cured product of the prepreg. The thickness of the metal foil 13 is not particularly limited and varies depending on the performance required of the final printed circuit board. The thickness of the metal foil 13 can be set appropriately according to 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, and if the metal foil is thin, it may be a carrier-equipped copper foil with a release layer and carrier to improve handling.

[0228] The method for manufacturing the metal-clad laminate 11 is not particularly limited as long as it can be manufactured. Specifically, one method is to manufacture the metal-clad laminate 11 using the prepreg 1. This method involves stacking one or more prepreg 1 sheets, further stacking metal foil 13 such as copper foil on both the top and bottom surfaces or one or both surfaces, and then heat-pressure-molding the metal foil 13 and the prepreg 1 to laminate and integrate them, thereby producing a laminate 11 with metal foil on both sides or one side. In other words, the metal-clad laminate 11 is obtained by laminating the metal foil 13 onto the prepreg 1 and then heat-pressure-molding it. The heating and pressing conditions can be appropriately set depending on the thickness of the metal-clad laminate 11 and the type of resin composition contained in the prepreg 1. For example, the temperature can be 170-230°C, the pressure 2-4 MPa, and the time 60-150 minutes. The metal-clad laminate may also be manufactured without using prepreg. For example, one method involves applying a varnish-like resin composition onto a metal foil to form a layer containing the resin composition on the metal foil, and then heating and pressurizing it.

[0229] The resin composition according to this embodiment is a resin composition that yields a cured product with a low relative permittivity and a low coefficient of thermal expansion. That is, when the resin composition is cured, it becomes a cured product with a low relative permittivity and a low coefficient of thermal expansion. Therefore, a metal-clad laminate having an insulating layer containing the cured product of this resin composition is a metal-clad laminate having an insulating layer containing a cured product with a low relative permittivity and a low coefficient of thermal expansion. Furthermore, this metal-clad laminate can suitably manufacture a wiring board having an insulating layer containing a cured product with a low relative permittivity and a low coefficient of thermal expansion.

[0230] [Wiring board] Figure 3 is a schematic cross-sectional view showing an example of a wiring board 21 according to an embodiment of the present invention.

[0231] As shown in Figure 3, the wiring board 21 according to this embodiment has an insulating layer 12 containing a cured product of the resin composition and wiring 14 provided on the insulating layer 12. Examples of the wiring board 21 include a wiring board composed of an insulating layer 12 made by curing the prepreg 1 shown in Figure 1, and wiring 14 laminated together with the insulating layer 12 and formed by partially removing the metal foil 13. Furthermore, the insulating layer 12 may be made of a cured product of the resin composition, or it may be made of a cured product of the prepreg.

[0232] The method for manufacturing the wiring board 21 is not particularly limited as long as it can be manufactured. Specifically, one example is a method of manufacturing the wiring board 21 using the prepreg 1. This method includes, for example, manufacturing a 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 to form wiring. That is, the wiring board 21 is obtained by partially removing the metal foil 13 on the surface of the metal-clad laminate 11 to form a circuit. In addition to the above method, other methods for circuit formation include, for example, circuit formation by the semi-additive process (SAP) or the modified semi-additive process (MSAP).

[0233] The resin composition according to this embodiment is a resin composition that yields a cured product with a low relative permittivity and a low coefficient of thermal expansion. That is, when the resin composition is cured, it becomes a cured product with a low relative permittivity and a low coefficient of thermal expansion. Therefore, a wiring board having an insulating layer containing the cured product of this resin composition is a wiring board having an insulating layer containing a cured product with a low relative permittivity and a low coefficient of thermal expansion.

[0234] [Metal foil with resin coating] Figure 4 is a schematic cross-sectional view showing an example of a resin-coated metal foil 31 according to this embodiment.

[0235] As shown in Figure 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. This resin-coated metal foil 31 has the metal foil 13 on the surface of the resin layer 32. That is, this resin-coated metal foil 31 comprises the resin layer 32 and the metal foil 13 laminated together with the resin layer 32. In addition, the resin-coated metal foil 31 may have other layers between the resin layer 32 and the metal foil 13.

[0236] The resin layer 32 may contain a semi-cured product of the resin composition as described above, or it 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 stage B) and a metal foil, or it may comprise a resin layer containing the uncured resin composition (the resin composition in stage A) and a metal foil. Furthermore, 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. 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. Furthermore, the fibrous substrate may be the same as the fibrous substrate of a prepreg.

[0237] The aforementioned metal foil can be any metal foil used in metal-clad laminates or resin-coated metal foils without limitation. Examples of such metal foils include copper foil and aluminum foil.

[0238] The resin-coated metal foil 31 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, but examples include polyolefin film, polyester film, polymethylpentene film, and films formed by providing a release agent layer on these films.

[0239] 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 applying the varnish-like resin composition (resin varnish) onto the metal foil 13 and heating it. The varnish-like resin composition is applied onto the metal foil 13, for example, by using a bar coater. The applied resin composition is heated, for example, at a temperature of 40°C to 180°C for 0.1 minutes to 10 minutes. The heated resin composition is formed on the metal foil 13 as an uncured resin layer 32. The heating can cause the organic solvent to volatilize from the resin varnish, thereby reducing or removing the organic solvent.

[0240] The resin composition according to this embodiment is a resin composition that yields a cured product with a low relative permittivity and a low coefficient of thermal expansion. That is, when the resin composition is cured, it becomes a cured product with a low relative permittivity and a low coefficient of thermal expansion. For this reason, a resin-coated metal foil comprising a resin layer containing this resin composition or a semi-cured product of this resin composition is a resin-coated metal foil comprising a resin layer that yields an insulating layer containing a cured product with a low relative permittivity and a low coefficient of thermal expansion. This resin-coated metal foil can be used when manufacturing a wiring board having an insulating layer containing a cured product with a low relative permittivity and a low coefficient of thermal expansion. For example, a multilayer wiring board can be manufactured by laminating it on top of a wiring board. A wiring board obtained using such a resin-coated metal foil has an insulating layer containing a cured product with a low relative permittivity and a low coefficient of thermal expansion.

[0241] [Resin-coated film] Figure 5 is a schematic cross-sectional view showing an example of a resin-coated film 41 according to this embodiment.

[0242] As shown in Figure 5, the resin-coated film 41 according to this embodiment comprises a resin layer 42 containing the resin composition or a semi-cured product of the resin composition, and a support film 43. This resin-coated film 41 comprises the resin layer 42 and a support film 43 laminated together with the resin layer 42. The resin-coated film 41 may also have other layers between the resin layer 42 and the support film 43.

[0243] The resin layer 42 may contain a semi-cured product of the resin composition as described above, or it 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 of stage B) and a support film, or it may comprise a resin layer containing the uncured resin composition (the resin composition of stage A) and a support film. Furthermore, 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. 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. Furthermore, the fibrous substrate may be the same as the fibrous substrate of the prepreg.

[0244] The support film 43 can be any support film used for resin-coated films without limitation. Examples of such support films include polyester film, polyethylene terephthalate (PET) film, polyimide film, polyparabanic acid film, polyether ether ketone film, polyphenylene sulfide film, polyamide film, polycarbonate film, and electrically insulating films such as polyarylate film.

[0245] 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, but examples include polyolefin film, polyester film, and polymethylpentene film.

[0246] The support film and the cover film may be subjected to surface treatments such as matte treatment, corona treatment, release treatment, and roughening treatment, as needed.

[0247] The method for manufacturing the resin-coated film 41 is not particularly limited as long as it can be manufactured. Examples of methods for manufacturing the resin-coated film 41 include applying the varnish-like resin composition (resin varnish) onto a support film 43 and heating it. The varnish-like resin composition is applied onto the support film 43, for example, by using a bar coater. The applied resin composition is heated, for example, at a temperature of 40°C to 180°C for 0.1 minutes to 10 minutes. The heated resin composition is formed on the support film 43 as an uncured resin layer 42. The heating can cause organic solvents to volatilize from the resin varnish, thereby reducing or removing the organic solvents.

[0248] The resin composition according to this embodiment is a resin composition that yields a cured product with a low dielectric constant and a low coefficient of thermal expansion. That is, when the resin composition is cured, it becomes a cured product with a low dielectric constant and a low coefficient of thermal expansion. For this reason, a resin-coated film comprising a resin layer containing this resin composition or a semi-cured product of this resin composition is a resin-coated film comprising a resin layer that yields an insulating layer containing a cured product with a low dielectric constant and a low coefficient of thermal expansion. This resin-coated film can be suitably used in the manufacture of a wiring board having an insulating layer containing a cured product with a low dielectric constant and a low coefficient of thermal expansion. For example, a multilayer wiring board can be manufactured by laminating it onto a wiring board and then peeling off the support film, or by laminating it onto a wiring board after peeling off the support film. A wiring board obtained using such a resin-coated film has an insulating layer containing a cured product with a low dielectric constant and a low coefficient of thermal expansion.

[0249] As described above, this specification discloses various aspects of technology, the main technologies among them are summarized below.

[0250] The resin composition according to the first embodiment comprises at least one curable compound (A) selected from the group consisting of maleimide compounds, benzoxazine compounds, and hydrocarbon compounds, and polysilsesquioxane particles (B), wherein the polysilsesquioxane particles (B) have in their molecule a structural unit represented by the following formula (1) and at least one selected from the following structural units represented by formulas (2) to (5), the ratio of the number of Si atoms contained in the structural unit represented by formula (1) in the polysilsesquioxane particles (B) to the total number of Si atoms contained in each of the following structural units represented by formulas (1) to (5) is 70% or more and less than 100%, and the ratio of the total number of Si atoms contained in each of the following structural units represented by formulas (2) to (4) in the polysilsesquioxane particles (B) to the total number of Si atoms contained in each of the following structural units represented by formulas (1) to (5) is greater than 0% and 20% or less.

[0251] [ka]

[0252] In formula (1), R1 represents an alkyl group or an aryl group.

[0253] [ka]

[0254] In formula (2), R2 represents an alkyl group or an aryl group.

[0255] [ka]

[0256] [ka]

[0257] [ka]

[0258] The resin composition according to the second embodiment is a resin composition according to the first embodiment in which the polysilsesquioxane particles (B) contain polysilsesquiosane with a random structure.

[0259] The third aspect of the resin composition is a resin composition according to the first or second aspect, wherein the hydrocarbon compound comprises at least one of a polyfunctional vinyl aromatic copolymer and a hydrocarbon compound represented by the following formula (6).

[0260] [ka]

[0261] In formula (6), X represents a hydrocarbon group having 6 or more carbon atoms, comprising at least one selected from aromatic cyclic groups and aliphatic cyclic groups, and n represents 1 to 10.

[0262] The fourth aspect of the resin composition is a resin composition that further comprises a reactive compound (C) that reacts with the curable compound (A) in any one of the first to third aspects of the resin composition.

[0263] The fifth embodiment of the resin composition is a resin composition according to any one of the first to fourth embodiments, wherein the content of the polysilsesquioxane particles (B) is 10 to 200 parts by mass per 100 parts by mass of the resin component.

[0264] The prepreg according to the sixth embodiment is a prepreg comprising a resin composition according to any one of the first to fifth embodiments or a semi-cured product of the resin composition and a fibrous substrate.

[0265] The seventh embodiment of the resin-coated film is a resin-coated film comprising a resin layer containing a resin composition according to any one of the first to fifth embodiments or a semi-cured product of the resin composition, and a support film.

[0266] The eighth aspect of the resin-coated metal foil is a resin-coated metal foil comprising a resin layer containing a resin composition according to any one of the first to fifth aspects or a semi-cured product of the resin composition, and a metal foil.

[0267] The metal-clad laminate according to the ninth embodiment is a metal-clad laminate comprising an insulating layer containing a cured product of a resin composition according to any one of the first to fifth embodiments, and a metal foil.

[0268] The metal-clad laminate according to the tenth embodiment is a metal-clad laminate comprising an insulating layer containing a cured prepreg according to the sixth embodiment and a metal foil.

[0269] The metal-clad laminate according to the 11th embodiment is a wiring board comprising an insulating layer containing a cured resin composition according to any one of the first to fifth embodiments, and wiring.

[0270] The metal-clad laminate according to the twelfth embodiment is a wiring board comprising an insulating layer containing a cured prepreg according to the sixth embodiment and wiring.

[0271] 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]

[0272] [Examples 1-5 and Comparative Examples 1-3] In this embodiment, each component used in preparing the resin composition will be described.

[0273] (curable compound) Maleimide compound-1: Solid content in MIR-5000-60T manufactured by Nippon Kayaku Co., Ltd. Maleimide compound-2: Solid content in MIR-3000-70MT manufactured by Nippon Kayaku Co., Ltd. Hydrocarbon compounds: These are polyfunctional vinyl aromatic copolymers obtained by the following reaction.

[0274] 3.0 moles (390.6 g) of divinylbenzene, 1.8 moles (229.4 g) of ethylvinylbenzene, 10.2 moles (1066.3 g) of styrene, and 15.0 moles (1532.0 g) of n-propyl acetate were placed in a 5.0 L reactor. 600 mmol of diethyl ether complex of boron trifluoride was added at 70°C, and the reaction was allowed to proceed for 4 hours. Afterward, to stop the reaction, an aqueous sodium bicarbonate solution was added to the resulting reaction solution, followed by washing the oil layer three times with pure water. The solid was then recovered by defloration under reduced pressure at 60°C. The obtained solid was weighed, and it was confirmed that 896.7 g was obtained.

[0275] The structure of the obtained solid (polymer) was determined using a JNM-LA600 nuclear magnetic resonance spectrometer manufactured by JEOL Ltd. 13 C-NMR and 1The results were measured by 1H-NMR analysis. Chloroform-d1 was used as the solvent, and the resonance line of tetramethylsilane was used as an internal standard. Furthermore, 13 C-NMR and 1 In addition to the 1H-NMR measurement results, the amount of a specific structural unit introduced into the copolymer was calculated from the data on the total amount of each structural unit introduced into the copolymer obtained from GC analysis. The amount of pendant vinyl group units contained in the polyfunctional vinyl aromatic copolymer was then calculated from the amount of this specific structural unit introduced at the end and the number-average molecular weight obtained from the GPC measurement.

[0276] The obtained solid is as described above. 13 C-NMR and 1 By performing 1H-NMR analysis, resonance lines originating from each monomer unit were observed. Furthermore, based on the NMR measurement results and GC analysis results, it was determined that this solid is the polyfunctional vinyl aromatic copolymer. Based on the NMR measurement results and GC analysis results, the constituent units of this polyfunctional vinyl aromatic copolymer were calculated as follows: structural units derived from divinylbenzene accounted for 30.4 mol% (33.1 mass%), structural units derived from styrene accounted for 57.4 mol% (52.7 mass%), structural units derived from ethyl vinylbenzene accounted for 12.2 mol% (14.2 mass%), and structural units with residual vinyl groups derived from divinylbenzene accounted for 23.9 mol% (25.9 mass%).

[0277] The molecular weight and molecular weight distribution of the obtained solid (polyfunctional vinyl aromatic copolymer) were measured using a GPC (HLC-8120GPC manufactured by Tosoh Corporation), with tetrahydrofuran as the solvent, a flow rate of 1.0 ml / min, a column temperature of 38°C, and a calibration curve using monodisperse polystyrene. As a result, the number-average molecular weight Mn of the obtained solid was 2980, the weight-average molecular weight Mw was 41300, and the Mw / Mn ratio was 13.9.

[0278] Benzooxazine compound: ALP-d manufactured by Shikoku Chemicals Co., Ltd. (catalyst) PBP: α,α'-di(t-butylperoxy)diisopropylbenzene (Perbutyl P(PBP) manufactured by NOF Corporation) (filling material) Polysilsesquioxane particles-1: BQ1510-SB made of TAT (structural unit represented by formula (1) above (T 3 R1 in the structure and the structural unit (T) represented by formula (2) above 2 In the structure, R2 is a methyl group, [T 3 / (T 3 +T 2 +Q 2 +Q 3 +Q 4 )]:91%, [T 2 / (T 3 +T 2 +Q 2 +Q 3 +Q 4 )]:9%, hydroxyl equivalent: 778.18g / eq) Polysilsesquioxane particles-2: BQ1510-SSB made of TAT (structural unit represented by formula (1) above (T 3 R1 in the structure and the structural unit (T) represented by formula (2) above 2 In the structure, R2 is a methyl group, [T 3 / (T 3 +T 2 +Q 2 +Q 3 +Q 4 )]:94%, [T 2 / (T 3 +T 2 +Q 2 +Q 3 +Q 4 )]:6%, hydroxyl equivalent: 1110.42g / eq) Polysilsesquioxane particles-3: BQQ1510 made of TAT (structural unit represented by formula (1) above (T 3 R1 in the structure and the structural unit (T) represented by formula (2) above 2 In the structure, R2 is a methyl group, [T 3 / (T 3 +T 2 +Q 2 +Q 3 +Q 4 )]:85.9%, [T 2 / (T 3 +T 2 +Q 2 +Q 3 +Q 4 )]: 11.5%, [Q 3 / (T 3 +T 2 +Q 2 +Q 3 +Q 4 )]: 1.1%, [Q 4 / (T 3 +T 2 +Q 2 +Q 3 +Q 4 )]:1.5%, [(T 2 +Q 2 +Q 3 ) / (T 3 +T 2 +Q 2 +Q 3 +Q 4 )]:14.1%, hydroxyl equivalent: 540.25g / eq) Spherical silica: Spherical silica surface-treated with a silane coupling agent containing vinyl groups in its molecule (vinylsilane-treated spherical silica, SC2050-MNU manufactured by Admatex Co., Ltd.) [Preparation method] First, the components other than the filler were added to methyl ethyl ketone (MEK) in the composition (parts by mass) listed in Table 1, so that the solid content concentration was 50% by mass, and the mixture was mixed. The resulting mixture was stirred for 60 minutes. Then, the filler was added to the resulting liquid in the composition (parts by mass) listed in Table 1, and dispersed using a bead mill. In this way, a varnish-like resin composition (varnish) was obtained.

[0279] Next, the prepreg was obtained as follows.

[0280] The obtained varnish was impregnated into a fibrous substrate (glass cloth: NEA2116-S201 manufactured by Nitto Boseki Co., Ltd.), and then heated and dried at 120-150°C for 3 minutes to prepare a prepreg. At that time, the content of the components constituting the resin composition in the prepreg (resin content) was adjusted to 40-50% by mass as a result of the curing reaction.

[0281] The resin compositions and prepregs prepared as described above were evaluated by the following method.

[0282] [Dielectric properties (relative permittivity)] Copper foil (3EC-LPIII, 12 μm thick, manufactured by Mitsui Mining & Smelting Co., Ltd.) was placed on both sides of each obtained prepreg. This was used as the pressure-bearing body and heated to 220°C at a heating rate of 3°C / min. By heating and pressurizing at 220°C for 120 minutes under a pressure of 2 MPa, an evaluation substrate (metal-clad laminate) with copper foil bonded to both sides and a thickness of approximately 0.1 mm was obtained.

[0283] An unclad plate, obtained by etching away the copper foil from the aforementioned evaluation substrate (metal-clad laminate), was used as a test specimen, and its relative permittivity at 10 GHz was measured using the cavity resonator perturbation method. Specifically, a network analyzer (N5230A manufactured by Agilent Technologies, Inc.) was used to measure the relative permittivity of the evaluation substrate at 10 GHz.

[0284] [Coefficient of thermal expansion] An unclad plate, obtained by etching away the copper foil from the aforementioned evaluation substrate (metal-clad laminate), was used as a test specimen, and the coefficient of thermal expansion in the Y-axis direction (CTE: ppm / °C) was measured by TMA (Thermo-mechanical Analysis) according to JIS C 6481. A TMA apparatus (TMA6000 manufactured by SII Nanotechnology Co., Ltd.) was used for the measurement, and measurements were taken in the range of 50 to 260°C.

[0285] [Copper foil peel strength] The copper foil was peeled off the evaluation substrate (metal-clad laminate), and the peel strength was measured in accordance with JIS C 6481 (1996). Specifically, a pattern with a width of 10 mm, a length of 100 mm, and a thickness of 0.012 mm was formed on the evaluation substrate, and the copper foil was peeled off at a speed of 50 mm / min using a tensile testing machine, and the peel strength (N / mm) at that time was measured.

[0286] The results for each of the above evaluations are shown in Table 1. Note that the parentheses [( )] in the filler category indicate the percentage (by volume) of the filler relative to the resin composition.

[0287] The results for each of the above evaluations are shown in Table 1.

[0288] [Table 1]

[0289] As can be seen from Table 1, for the resin composition containing the curable compound (A), [T 3 / (T 3 +T 2 +Q 2 +Q 3 +Q 4 )] is 70% or more and less than 100%, and [(T 2 +Q 2 +Q 3 ) / (T 3 +T 2 +Q 2 +Q 3 +Q 4 When polysilsesquioxane particles (B) in a concentration of more than 0% and less than or equal to 20% (Examples 1-5) were included, the resulting cured resin composition had a lower coefficient of thermal expansion compared to cases where no filler such as polysilsesquioxane particles was included (Comparative Examples 1 and 2). Furthermore, even when the resin compositions in Examples 1-5 included a filler, the resulting cured resin composition had a lower dielectric constant compared to cases where spherical silica was included as a filler (Comparative Example 3). From these findings, it was found that when polysilsesquioxane particles (B) are included as a filler, a resin composition with a low dielectric constant and a low coefficient of thermal expansion can be obtained. Moreover, even when polysilsesquioxane particles (B) are included, a resin composition with a low dielectric constant and a low coefficient of thermal expansion can be obtained while suppressing (without significantly reducing) the decrease in copper foil peel strength. [Explanation of Symbols]

[0290] 1 Prepreg 2. Resin composition or semi-cured resin composition 3. Fibrous base material 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 43 Support film

Claims

1. A curable compound (A) selected from the group consisting of maleimide compounds, benzoxazine compounds, and hydrocarbon compounds, Contains polysilsesquioxane particles (B), The polysilsesquioxane particles (B) contain polysilsesquioxane with a random structure. The polysilsesquioxane particle (B) has in its molecule a structural unit represented by the following formula (1) and at least one selected from the structural units represented by the following formulas (2) to (5). In the polysilsesquioxane particles (B), the ratio of the number of Si atoms contained in the structural unit represented by the following formula (1) to the total number of Si atoms contained in each of the structural units represented by the following formulas (1) to (5) is 70% or more and less than 100%. A resin composition in which the ratio of the total number of Si atoms contained in each of the structural units represented by the following formulas (2) to (4) in the polysilsesquioxane particles (B) to the total number of Si atoms contained in each of the structural units represented by the following formulas (1) to (5) is greater than 0% and less than or equal to 20%. 【Chemistry 1】 [In formula (1), R １ This represents an alkyl group or an aryl group. 【Chemistry 2】 [In formula (2), R ２ This represents an alkyl group or an aryl group. 【Transformation 3】 【Chemistry 4】 【Transformation 5】

2. The resin composition according to claim 1, wherein the particle size of the polysilsesquioxane particles (B) is 0.01 to 10 μm in volume average particle size.

3. The resin composition according to claim 1, wherein the hydroxyl group equivalent of the polysilsesquioxane particles (B) is 300 to 3000 g / eq.

4. The resin composition according to claim 1, wherein the hydrocarbon compound comprises at least one of a polyfunctional vinyl aromatic copolymer and a hydrocarbon compound represented by the following formula (6). 【Transformation 6】 [In formula (6), X represents a hydrocarbon group having 6 or more carbon atoms, comprising at least one selected from aromatic cyclic groups and aliphatic cyclic groups, and n represents 1 to 10.]

5. The resin composition according to claim 1, further comprising a reactive compound (C) that reacts with the curable compound (A).

6. The resin composition according to claim 1, wherein the content of the polysilsesquioxane particles (B) is 10 to 200 parts by mass per 100 parts by mass of the resin component.

7. A prepreg comprising a resin composition according to any one of claims 1 to 6 or a semi-cured product of the resin composition, and a fibrous substrate.

8. A resin-coated film comprising a resin layer containing the resin composition described in any one of claims 1 to 6 or a semi-cured product of the resin composition, and a support film.

9. A resin-coated metal foil comprising a resin layer containing the resin composition according to any one of claims 1 to 6 or a semi-cured product of the resin composition, and a metal foil.

10. A metal-clad laminate comprising an insulating layer containing a cured product of the resin composition according to any one of claims 1 to 6, and a metal foil.

11. A metal-clad laminate comprising an insulating layer containing a cured prepreg according to claim 7, and a metal foil.

12. A wiring board comprising an insulating layer containing a cured resin composition according to any one of claims 1 to 6, and wiring.

13. A wiring board comprising an insulating layer containing a cured prepreg according to claim 7, and wiring.

Images