Resin composition, and prepreg, film with resin, metal foil with resin, metal-clad laminate, and wiring board each using same

Abstract

One aspect of the present invention relates to a resin composition which contains a polyphenylene ether compound (A) that has a functional group containing a carbon-carbon unsaturated double bond, a silica filler (B), and a curing agent (C), wherein: the silica filler (B) has an average particle diameter of 0.5 μm or more and 5.0 μm or less, the average particle diameter being obtained by arithmetically averaging the volume-based frequency distribution of the particle size distribution; and when D10 is the volume-based 10% cumulative particle diameter, D50 is the volume-based 50% cumulative particle diameter, and D90 is the volume-based 90% cumulative particle diameter in the particle size distribution of the silica filler (B), at least one of the ratio V (D10 / D50) of the D10 to the D50 and the ratio W (D50 / D90) of the D50 to the D90 is 0.6 or more in cases where the average particle diameter is less than 1.0 μm, and is 0.7 or more in cases where the average particle diameter is 1.0 μm or more.

Description

Resin composition, and prepreg, resin-coated film, resin-coated metal foil, metal-clad laminate, and wiring board using the same

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

[0002] In recent years, with the increase in the amount of information processed in various electronic devices, there has been rapid progress in packaging technologies, such as higher integration of semiconductor devices, higher density wiring, and multi-layering. Thermosetting resins are generally used as substrate materials for the base materials of wiring boards used in various electronic devices, and they are required to have high heat resistance (glass transition temperature) to cope with high temperatures such as reflow and multi-layering, as well as low dielectric constant and dielectric loss tangent to increase signal transmission speed and reduce loss during signal transmission.

[0003] Examples of substrate materials for forming the insulating layer of such wiring boards include resin compositions described in Patent Document 1.

[0004] Patent Document 1 discloses a polyphenylene ether resin composition comprising: (A) a modified polyphenylene ether copolymer in which phenolic hydroxyl groups at the molecular terminals of a polyphenylene ether copolymer are modified with a compound having a carbon-carbon unsaturated double bond; and (B) a high molecular weight substance having a glass transition temperature (Tg) of 20°C or lower as measured by DSC and a number average molecular weight Mn of 1,000 to 10,000, wherein the polyphenylene ether resin composition is characterized in that the component (A) and the component (B) undergo phase separation in a cured state.

[0005] The resin composition containing the polyphenylene ether compound described in Patent Document 1 is said to be capable of suppressing warpage of the substrate material while maintaining excellent dielectric properties.

[0006] On the other hand, resin compositions used in substrate materials are required to have good adhesion in their cured products, but adding silica filler to a resin composition often causes problems with interlayer adhesion when used as a substrate material.

[0007] JP 2017-128718 A

[0008] The present invention has been made in view of the above circumstances, and aims to provide a resin composition that has low dielectric properties and excellent adhesion in a cured product, as well as a prepreg, a resin-coated film, a resin-coated metal foil, a metal-clad laminate, and a wiring board using the resin composition.

[0009] A resin composition according to one aspect of the present invention includes a polyphenylene ether compound (A) having a functional group containing a carbon-carbon unsaturated double bond, a silica filler (B), and a curing agent (C), wherein the silica filler (B) has an average particle size of 0.5 μm or more and 5.0 μm or less, which is obtained by arithmetically averaging the volume-based frequency distribution in the particle size distribution, and wherein, in the particle size distribution of the silica filler (B), when D10 is the volume-based cumulative 10% particle size, D50 is the volume-based cumulative 50% particle size, and D90 is the volume-based cumulative 90% particle size, at least one of V (D10 / D50), a ratio of D10 to D50, and W (D50 / D90), a ratio of D50 to D90, is 0.6 or more when the average particle size is less than 1.0 μm, and is 0.7 or more when the average particle size is 1.0 μm or more.

[0010] Fig. 1 is a schematic cross-sectional view showing the configuration of a prepreg according to one embodiment of the present invention. Fig. 2 is a schematic cross-sectional view showing the configuration of a metal-clad laminate according to one embodiment of the present invention. Fig. 3 is a schematic cross-sectional view showing the configuration of a wiring board according to one embodiment of the present invention. Fig. 4 is a schematic cross-sectional view showing the configuration of a resin-coated metal foil according to one embodiment of the present invention. Fig. 5 is a schematic cross-sectional view showing the configuration of a resin-coated film according to one embodiment of the present invention.

[0011] (Resin Composition) A resin composition according to an embodiment of the present invention (hereinafter also referred to simply as the resin composition) includes a polyphenylene ether compound (A) having a functional group containing a carbon-carbon saturated double bond, a silica filler (B), and a curing agent (C). The silica filler (B) has an average particle size of 0.5 μm or more and 5.0 μm or less. Furthermore, when the volume-based cumulative 10% particle size in the particle size distribution of the silica filler (B) is defined as D10, the volume-based cumulative 50% particle size is defined as D50, and the volume-based cumulative 90% particle size is defined as D90, at least one of the ratio V (D10 / D50) of D10 to D50 and the ratio W (D50 / D90) of D50 to D90 is 0.6 or more when the average particle size is less than 1.0 μm, and 0.7 or more when the average particle size is 1.0 μm or more.

[0012] The resin composition of this embodiment contains the polyphenylene ether compound (A), the silica filler (B), and the curing agent (C), and thus the cured product of the resin composition can have low dielectric properties. Furthermore, since the silica filler (B) has the above-mentioned structure, the resin composition of this embodiment also has excellent adhesion (particularly interlayer adhesion), making it very useful for industrial applications.

[0013] That is, according to the present invention, a resin composition can be provided that has low dielectric properties in the cured product and also has excellent interlayer adhesion. Furthermore, by using the resin composition, it is possible to provide a prepreg, a resin-coated film, a resin-coated metal foil, a metal-clad laminate, and a wiring board that have excellent properties.

[0014] Each component of the resin composition according to this embodiment will be specifically described below.

[0015] <Polyphenylene ether compound (A)> The polyphenylene ether compound that can be used in the present embodiment is not particularly limited as long as it is a polyphenylene ether compound having a functional group containing a carbon-carbon unsaturated double bond in the molecule. Specific examples of polyphenylene ether compounds having a functional group containing a carbon-carbon unsaturated double bond include polyphenylene ether compounds having a group represented by the following formula (1) or formula (2). It is believed that the inclusion of such a modified polyphenylene ether compound results in a resin composition that can give a cured product with low dielectric properties and high heat resistance.

[0016]

[0017] In formula (1), s represents an integer of 0 to 10. Z represents an arylene group. １ ~R ３ are independent of each other. That is, R １ ~R ３ may be the same group or different groups. １ ~R ３ represents a hydrogen atom or an alkyl group.

[0018] In addition, in formula (1), when s is 0, this indicates that Z is directly bonded to the end of the polyphenylene ether.

[0019] The arylene group represented by Z is not particularly limited. Examples of the arylene group include monocyclic aromatic groups such as a phenylene group, and polycyclic aromatic groups in which the aromatic ring is not monocyclic but is a polycyclic aromatic ring such as a naphthalene ring. The arylene group also includes derivatives in which a hydrogen atom bonded to the aromatic ring is substituted with a functional group such as an alkenyl group, an alkynyl group, a formyl group, an alkylcarbonyl group, an alkenylcarbonyl group, or an alkynylcarbonyl group. The alkyl group is not particularly limited, and is preferably an alkyl group having 1 to 18 carbon atoms, more preferably an alkyl group having 1 to 10 carbon atoms. Specific examples include a methyl group, an ethyl group, a propyl group, a hexyl group, and a decyl group.

[0020]

[0021] In formula (2), R ４ represents a hydrogen atom or an alkyl group. The alkyl group is not particularly limited, and is preferably, for example, an alkyl group having 1 to 18 carbon atoms, more preferably an alkyl group having 1 to 10 carbon atoms. Specific examples include a methyl group, an ethyl group, a propyl group, a hexyl group, and a decyl group.

[0022] Preferred specific examples of the substituent represented by formula (1) include, for example, a substituent containing a vinylbenzyl group. Examples of the substituent containing a vinylbenzyl group include, for example, a substituent represented by formula (3) below. Furthermore, examples of the substituent represented by formula (2) include an acrylate group and a methacrylate group.

[0023]

[0024] More specific examples of the substituent include vinylbenzyl groups (ethenylbenzyl groups) such as p-ethenylbenzyl and m-ethenylbenzyl groups, vinylphenyl groups, acrylate groups, and methacrylate groups.

[0025] The polyphenylene ether compound has a polyphenylene ether chain in the molecule, and preferably has, for example, a repeating unit represented by the following formula (4) in the molecule.

[0026]

[0027] In formula (4), t represents 1 to 50. ５ ~R ８ are independent of each other. That is, R ５ ~R ８ may be the same group or different groups. ５ ~R ８ 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 which a hydrogen atom and an alkyl group are preferred.

[0028] R ５ ~R８ Specific examples of the functional groups mentioned in the above include the following:

[0029] The alkyl group is not particularly limited, but is preferably an alkyl group having 1 to 18 carbon atoms, and more preferably an alkyl group having 1 to 10 carbon atoms. Specific examples include a methyl group, an ethyl group, a propyl group, a hexyl group, and a decyl group.

[0030] The alkenyl group is not particularly limited, but is preferably an alkenyl group having 2 to 18 carbon atoms, and more preferably an alkenyl group having 2 to 10 carbon atoms. Specific examples include a vinyl group, an allyl group, and a 3-butenyl group.

[0031] The alkynyl group is not particularly limited, but is preferably an alkynyl group having 2 to 18 carbon atoms, and more preferably an alkynyl group having 2 to 10 carbon atoms. Specific examples include an ethynyl group and a prop-2-yn-1-yl group (propargyl group).

[0032] The alkylcarbonyl group is not particularly limited as long as it is a carbonyl group substituted with an alkyl group, but for example, an alkylcarbonyl group having 2 to 18 carbon atoms is preferred, and an alkylcarbonyl group having 2 to 10 carbon atoms is more preferred. Specific examples include an acetyl group, a propionyl group, a butyryl group, an isobutyryl group, a pivaloyl group, a hexanoyl group, an octanoyl group, and a cyclohexylcarbonyl group.

[0033] 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. Specific examples include an acryloyl group, a methacryloyl group, and a crotonoyl group.

[0034] 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. Specific examples include a propioloyl group.

[0035] The weight-average molecular weight (Mw) of the polyphenylene ether compound is not particularly limited. Specifically, it is preferably 500 to 5,000, more preferably 800 to 4,000, and even more preferably 1,000 to 3,000. The weight-average molecular weight may be measured by a general molecular weight measurement method, specifically, a value measured using gel permeation chromatography (GPC), etc. Furthermore, when the polyphenylene ether compound has a repeating unit represented by the formula (4) in the molecule, t is preferably a value such that the weight-average molecular weight of the polyphenylene ether compound falls within this range. Specifically, t is preferably 1 to 50.

[0036] When the weight-average molecular weight of the polyphenylene ether compound is within this range, it is believed that the compound will have the excellent low dielectric properties of polyphenylene ether, and will not only have superior heat resistance but also excellent moldability in the cured product. This is believed to be due to the following reasons. When the weight-average molecular weight of a typical polyphenylene ether is within this range, it has a relatively low molecular weight, and the heat resistance of the cured product tends to decrease. In this regard, the polyphenylene ether compound according to this embodiment has one or more unsaturated double bonds at its terminals, and therefore is believed to be able to obtain a cured product with sufficiently high heat resistance. Furthermore, when the weight-average molecular weight of the polyphenylene ether compound is within this range, it is believed to have a relatively low molecular weight, and therefore is believed to be able to obtain a cured product with excellent moldability. Therefore, it is believed that such a polyphenylene ether compound will not only have superior heat resistance but also excellent moldability in the cured product.

[0037] The average number of the substituents (number of terminal functional groups) at the molecular terminals per molecule of the polyphenylene ether compound is not particularly limited. Specifically, it is preferably 1 to 3, and more preferably 1.5 to 3. If the number of terminal functional groups is too small, it tends to be difficult to obtain a cured product with sufficient heat resistance. Furthermore, if the number of terminal functional groups is too large, the reactivity becomes too high, which may cause problems such as reduced shelf life and reduced fluidity of the resin composition. That is, when such a polyphenylene ether compound is used, insufficient fluidity may cause molding defects such as the generation of voids during multilayer molding, leading to moldability problems such as difficulty in obtaining a highly reliable printed wiring board. Therefore, the polyphenylene ether compound (A) of this embodiment preferably contains a polyphenylene ether compound (A-1) having 1 to 3 functional groups per molecule.

[0038] The number of terminal functional groups of a polyphenylene ether compound may be, for example, a numerical value representing the average number of the substituents per molecule of all modified polyphenylene ether compounds present 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 modified polyphenylene ether compound and calculating the difference from the number of hydroxyl groups in the polyphenylene ether before modification. This difference from the number of hydroxyl groups in the polyphenylene ether before modification is the number of terminal functional groups. The number of hydroxyl groups remaining in the modified polyphenylene ether compound can be measured by adding a quaternary ammonium salt (tetraethylammonium hydroxide) that associates with hydroxyl groups to a solution of the modified polyphenylene ether compound and measuring the UV absorbance of the resulting mixed solution.

[0039] Examples of the polyphenylene ether compound of the present embodiment include a modified polyphenylene ether compound represented by the following formula (5) and a modified polyphenylene ether compound represented by the following formula (6). Furthermore, as the polyphenylene ether compound of the present embodiment, these modified polyphenylene ether compounds may be used alone, or these two types of modified polyphenylene ether compounds may be used in combination.

[0040]

[0041]

[0042] In formula (5) and formula (6), R ９ ~R １６ and R １７ ~R ２４ each independently 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. １ and X ２ each independently represents a substituent having a carbon-carbon unsaturated double bond. A and B represent repeating units represented by the following formulas (7) and (8), respectively. In addition, in formula (6), Y represents a linear, branched, or cyclic hydrocarbon having 20 or less carbon atoms.

[0043]

[0044]

[0045] In formula (7) and formula (8), m and n each represent an integer of 0 to 20. ２５ ~R ２８ and R ２９ ~R ３２ each independently 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.

[0046] The modified polyphenylene ether compound represented by the formula (5) and the modified polyphenylene ether compound represented by the formula (6) are not particularly limited as long as they satisfy the above-mentioned constitution. Specifically, in the formulas (5) and (6), R ９ ~R １６ and R １７ ~R ２４ As described above, each of R is independent. ９ ~R １６ and R １７ ~R ２４ may be the same group or different groups. ９ ~R １６ and R １７ ~R ２４ 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 which a hydrogen atom and an alkyl group are preferred.

[0047] In formula (7) and formula (8), m and n each preferably represent a value of 0 to 20, as described above. Furthermore, it is preferable that m and n represent a numerical value such that the sum of m and n is 1 to 30. Therefore, it is more preferable that m represents a value of 0 to 20, n represents a value of 0 to 20, and the sum of m and n represents a value of 1 to 30. Furthermore, R ２５ ~R ２８ and R ２９ ~R ３２ are independent of each other. That is, R ２５ ~R ２８ and R ２９ ~R ３２ may be the same group or different groups. ２５ ~R ２８ and R ２９ ~R ３２ 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 which a hydrogen atom and an alkyl group are preferred.

[0048] R ９ ~R ３２is R in the above formula (4). ５ ~R ８ is the same as

[0049] In the formula (6), as described above, Y is a linear, branched, or cyclic hydrocarbon having 20 or less carbon atoms. Examples of Y include a group represented by the following formula (9).

[0050]

[0051] In the formula (9), R ３３ and R ３４ are each independently a hydrogen atom or an alkyl group. Examples of the alkyl group include a methyl group. Examples of the group represented by formula (9) include a methylene group, a methylmethylene group, and a dimethylmethylene group, and among these, a dimethylmethylene group is preferred.

[0052] In the formula (5) and the formula (6), X １ and X ２ are each independently a substituent (functional group) having a carbon-carbon unsaturated double bond. １ and X ２ There are no particular limitations on the substituent X as long as it is a substituent having a carbon-carbon unsaturated double bond. １ and X ２ Examples of the substituents include the substituents represented by the formula (1) and the substituents represented by the formula (2). In the modified polyphenylene ether compound represented by the formula (5) and the modified polyphenylene ether compound represented by the formula (6), X １ and X ２ may be the same substituent or different substituents.

[0053] More specific examples of the modified polyphenylene ether compound represented by the formula (5) include modified polyphenylene ether compounds represented by the following formula (10).

[0054]

[0055] More specific examples of the modified polyphenylene ether compound represented by formula (6) include a modified polyphenylene ether compound represented by formula (11) below and a modified polyphenylene ether compound represented by formula (12) below.

[0056]

[0057]

[0058] In the above formulas (10) to (12), m and n are the same as m and n in the above formulas (7) and (8). １ ~R ３ , p and Z are R in the above formula (1), respectively. １ ~R ３ , s, and Z. In the formulas (11) and (12), Y is the same as Y in the formula (6). In the formula (12), R ４ is R in the above formula (2). ４ is the same as

[0059] It is believed that by using the modified polyphenylene ether compound as described above, it is possible to improve adhesion while maintaining low dielectric properties such as low dielectric loss tangent and excellent heat resistance.

[0060] The modified polyphenylene ether compounds may be used singly or in combination of two or more.

[0061] The polyphenylene ether compound used in the resin composition of this embodiment can be synthesized by a known method, or a commercially available product can be used. Examples of commercially available products include "OPE-2st 1200" and "OPE-2st 2200" manufactured by Mitsubishi Gas Chemical Company, Inc., and "SA9000" manufactured by SABIC Innovative Plastics.

[0062] The content of the polyphenylene ether compound (A) is preferably 30% by mass or more and 80% by mass or less, and more preferably 35% by mass or more and 75% by mass or less, relative to 100% by mass of the total of the polyphenylene ether compound (A) and the curing agent (C). It is believed that within this mass% range, low dielectric properties can be more reliably ensured, plate thickness accuracy can be maintained, and low dielectric properties can be guaranteed. Therefore, by including the polyphenylene ether compound (A) in such a content, the resin composition of this embodiment can more reliably obtain low dielectric properties in its cured product.

[0063] <Silica Filler (B)> The silica filler (B) used in this embodiment has an average particle size of 0.5 μm or more and 5.0 μm or less. Furthermore, when the volume-based cumulative 10% particle size in the particle size distribution of the silica filler (B) is D10, the volume-based cumulative 50% particle size is D50, and the volume-based cumulative 90% particle size is D90, at least one of the ratio V (D10 / D50) of D10 to D50 and the ratio W (D50 / D90) of D50 to D90 is 0.6 or more when the average particle size is less than 1.0 μm, and 0.7 or more when the average particle size is 1.0 μm or more. By using such a silica filler (B), it is possible to improve adhesion (particularly interlayer adhesion) while maintaining low dielectric properties in the resin composition.

[0064] In this embodiment, the term "average particle size" refers to the arithmetic mean of the volume-based frequency distribution in the particle size distribution.

[0065] It is more preferable that the ratio (%) of the ratio V (D10 / D50) to the ratio W (D50 / D90) is 90% or more, which is considered to have the advantage of more reliably achieving both high adhesion and low dielectric loss.

[0066] In this specification, the average particle size and the particle size distribution are values ​​measured by particle size distribution measurement using a laser diffraction / scattering method, and can be measured using, for example, a laser diffraction / scattering particle size distribution measuring apparatus "LA-960V2" (manufactured by HORIBA, Ltd.) used in the examples described later.

[0067] The silica filler (B) is not particularly limited as long as it satisfies the above-mentioned requirements and can be used as an inorganic filler. Preferably, a spherical silica filler with a reduced hydroxyl group content is used. Preferably, the spherical silica filler does not contain silica fillers with a diameter of 50 nm or less.

[0068] The silica filler (B) as described above can be obtained, for example, by the following method.

[0069] First, R ｍ Six ３ By the hydrolysis and condensation reaction of the above, a spherical polysiloxane containing T units is obtained. ３ are hydrogen atoms or independently selectable organic groups having 1 to 18 carbon atoms, X is a hydrolyzable group, and the T units are R ３ SiO ３ The spherical polysiloxane is then calcined under a dry oxidizing gas atmosphere to obtain spherical silica powder with a low hydroxyl group content. The calcination temperature is between 850 and 1200°C. The obtained spherical silica powder has a Q １ Unit, Q ２ Unit, Q ３ Units and Q ４ It is composed of at least one unit selected from the following: １ The unit is Si(OH) ３ O- and Q ２ The unit is Si(OH) ２ O ２ - and Q ３ The unit is SiOHO ３ - and Q ４ The unit is SiO ４ - and Q ４ The content of the unit is greater than or equal to 95%.

[0070] In the silica filler (B) of this embodiment, it is preferable that the content of hydroxy groups (OH groups) is low. From this viewpoint, the Q ４ The content of the unit is preferably 95% or more, which is thought to have the advantage of reducing dielectric loss.

[0071] The hydrolyzable group is preferably an alkoxy group or a halogen atom. The catalyst for the hydrolysis condensation reaction may be a salt or an acid.

[0072] The oxidizing gas preferably contains oxygen gas to completely oxidize the organic compounds in the polysiloxane. A preferred oxygen gas is air. The calcination step is preferably carried out by electrical heating or indirect gas heating. The calcination temperature is more preferably between 850 and 1100°C, and the calcination time is preferably between 6 and 12 hours.

[0073] The spherical polysiloxane may further contain Q units, D units, and / or M units, where Q units = SiO ４ - and D unit = R ４ R ５ SiO ２ - and M unit = R ６ R ７ R ８ SiO ２ In the above chemical formula, R ４ , R ５ , R ６ , R ７ and R ８ are each independently selected hydrogen atoms or hydrocarbon groups of 1 to 18 carbon atoms.

[0074] Furthermore, the obtained spherical silica powder may be subjected to a surface treatment. That is, the silica filler (B) of this embodiment may be a surface-treated silica filler or a non-surface-treated silica filler. Examples of the surface treatment include treatment with a silane coupling agent.

[0075] Silane coupling agents that can be used for surface treatment include (R Ａ９ ) ａ (R Ａ１０ ) ｂ Si(M) ４－ａ－ｂ In the above chemical formula, R Ａ９ and R Ａ１０are independently selectable hydrocarbon groups having 1 to 18 carbon atoms, hydrogen atoms, or hydrocarbon groups having 1 to 18 carbon atoms substituted with a functional group. The functional groups include at least one selected from the group consisting of organic functional groups such as vinyl groups, allyl groups, styryl groups, epoxy groups, aliphatic amino groups, aromatic amino groups, methacryloxypropyl groups, acryloxypropyl groups, ureidopropyl groups, chloropropyl groups, mercaptopropyl groups, polysulfide groups, and isocyanatopropyl groups. M is an alkoxy group having 1 to 18 carbon atoms or a halogen atom, a=0, 1, 2, or 3, b=0, 1, 2, or 3, and a+b=1, 2, or 3, and the disilazane is represented by (R Ａ１１ R Ａ１２ R Ａ１３ )SiNHSi(R Ａ１４ R Ａ１５ R Ａ１６ ) and R Ａ１１ , R Ａ１２ , R Ａ１３ , R Ａ１４ , R Ａ１５ and R Ａ１６ is an independently selectable hydrocarbon group having 1 to 18 carbon atoms or a hydrogen atom.

[0076] The silica filler obtained as described above is preferably further subjected to dry or wet sieving or inertial classification to remove coarse particles of 1 μm, 3 μm, 5 μm, 10 μm, 20 μm or more from the spherical silica powder filler.

[0077] The content of the silica filler (B) is preferably 10 parts by mass or more and 400 parts by mass or less, and more preferably 30 parts by mass or more and 150 parts by mass or less, relative to 100 parts by mass of the total of the polyphenylene ether compound (A) and the curing agent (C) described below. By including the silica filler (B) in such an amount, it is believed that the resin composition of this embodiment can more reliably obtain low dielectric properties and excellent adhesion in the cured product thereof.

[0078] The resin composition of this embodiment may contain an inorganic filler other than the silica filler (B) as long as the effects of the present invention are not impaired. The inorganic filler other than the silica filler (B) is not particularly limited as long as it can be used as an inorganic filler contained in the resin composition. Specific examples include metal oxides such as alumina, titanium oxide, magnesium oxide, and mica, metal hydroxides such as aluminum hydroxide and magnesium hydroxide, talc, aluminum borate, barium sulfate, aluminum nitride, silicon nitride, magnesium carbonate such as anhydrous magnesium carbonate, boron nitride, calcium carbonate, and the like. Among these, anhydrous magnesium carbonate, alumina, silicon nitride, and the like are preferred.

[0079] <Curing Agent (C)> The resin composition of this embodiment contains a curing agent (C). The curing agent (C) is not particularly limited as long as it is a curing agent that reacts with the polyphenylene ether compound (A). Preferably, the curing agent (C) used in this embodiment contains a curing agent having a carbon-carbon unsaturated double bond in the molecule.

[0080] By including such a curing agent (C), the resin composition of this embodiment is thought to have advantages such as improved heat resistance, an increased glass transition temperature, and improved copper foil peel strength.

[0081] Specific examples of the curing agent (C) include at least one compound selected from the group consisting of polyfunctional methacrylate compounds, polyfunctional acrylate compounds, polyfunctional alkenyl compounds, and polyfunctional maleimide compounds, each of which has two or more reactive carbon-carbon unsaturated double bonds in the molecule. These compounds may be used alone or in combination of two or more.

[0082] Examples of polyfunctional methacrylate compounds include polyfunctional methacrylate compounds having two or more methacryloyl groups in the molecule, and more specifically, examples thereof include dimethacrylate compounds such as tricyclodecane dimethanol dimethacrylate (DCP).

[0083] Examples of polyfunctional acrylate compounds include polyfunctional acrylate compounds having two or more acryloyl groups in the molecule, and more specific examples include diacrylate compounds such as tricyclodecane dimethanol diacrylate.

[0084] The polyfunctional alkenyl compound may be a polyfunctional alkenyl compound having two or more alkenyl groups in the molecule.Specifically, a polybutadiene compound having two or more vinyl groups, or an allyl compound having two or more allyl groups in the molecule may be used, and examples thereof include triallyl isocyanurate compounds such as triallyl isocyanurate (TAIC), diallyl bisphenol compounds, and diallyl phthalate (DAP).

[0085] The polyfunctional maleimide compound may be any maleimide compound having two or more maleimide groups in the molecule, without any particular limitation. Specific examples include aromatic maleimide compounds containing an aromatic group in the molecule, imide group-containing maleimide compounds having an imide group in the molecule, aliphatic maleimide compounds containing a long-chain alkyl group in the molecule, and maleimide compounds having an arylene structure in the molecule that is bonded and oriented at the meta position.

[0086] Furthermore, it is preferable that the curing agent (C) further contains at least one selected from a polybutadiene compound having a number average molecular weight of 1,000 to 10,000, a butadiene-styrene copolymer, and an acrylate copolymer. This is believed to have the advantage of improving low dielectric properties. The polybutadiene compound is preferably liquid at room temperature and has a glass transition temperature (Tg) of 20°C or lower.

[0087] When the resin composition of this embodiment contains a curing agent (C), the content thereof is preferably 20% by mass or more and 70% by mass or less, and more preferably 25% by mass or more and 60% by mass or less, relative to 100% by mass of the total of the polyphenylene ether compound (A) and the curing agent (C). The content ratio of the polyphenylene ether compound (A) to the curing agent (C) is preferably 3:7 to 8:2, and more preferably 3.5:6.5 to 7.5:2.5, in mass ratio.

[0088] <Silane coupling agent (D)> The resin composition of this embodiment may contain a silane coupling agent (D) in addition to the above components. It is believed that this improves the adhesion between the polyphenylene ether compound (A) and the silica filler (B). The silane coupling agent (D) referred to here may be a silane coupling agent used for the surface treatment of the silica filler (B), or the surface-treated filler may be a silane coupling agent that is separately blended into the resin composition.

[0089] As the silane coupling agent (D), it is preferable to use a silane coupling agent having a functional group containing a carbon-carbon unsaturated bond. Examples include silane coupling agents having at least one functional group selected from the group consisting of a vinyl group, a styryl group, a methacryloyl group, an acryloyl group, and a phenylamino group. That is, the silane coupling agent has at least one reactive functional group selected from the group consisting of a vinyl group, a styryl group, a methacryloyl group, an acryloyl group, and a phenylamino group, and further includes compounds having a hydrolyzable group such as a methoxy group or an ethoxy group. These can be used alone or in combination of two or more.

[0090] More specific examples of the silane coupling agent (D) include those having a vinyl group, such as vinyltriethoxysilane and vinyltrimethoxysilane. Examples of the silane coupling agent having a styryl group include p-styryltrimethoxysilane and p-styryltriethoxysilane. Examples of the silane coupling agent having a methacryloyl group include 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, and 3-methacryloxypropylethyldiethoxysilane. Examples of the silane coupling agent having an acryloyl group include 3-acryloxypropyltrimethoxysilane and 3-acryloxypropyltriethoxysilane. Examples of the silane coupling agent include those having a phenylamino group, such as N-phenyl-3-aminopropyltrimethoxysilane and N-phenyl-3-aminopropyltriethoxysilane.

[0091] The content of the silane coupling agent (D) is preferably 0.1 parts by mass or more and 2.0 parts by mass or less, and more preferably 0.2 parts by mass or more and 1.5 parts by mass or less, relative to 100 parts by mass of the total of the polyphenylene ether compound (A) and the curing agent (C), whether it is added externally (added separately from the surface treatment of the silica filler (B)) or used in the surface treatment of the silica filler (B).

[0092] <Phosphorus-Based Flame Retardant (E)> The resin composition of this embodiment may further contain a phosphorus-based flame retardant (E) to enhance flame retardancy. Examples of the phosphorus-based flame retardant (E) include phosphate esters such as condensed phosphate esters and cyclic phosphate esters, phosphazene compounds such as cyclic phosphazene compounds, phosphinate-based flame retardants such as metal phosphinates such as aluminum dialkylphosphinates, melamine-based flame retardants such as melamine phosphate and melamine polyphosphate, and phosphine oxide compounds having diphenylphosphine oxide groups. These may be used alone or in combination of two or more. Preferably, the phosphorus-based flame retardant (E) is a phosphine oxide compound having a melting point of 280°C or higher and two or more diphenylphosphine oxide groups per molecule.

[0093] When the resin composition of the present embodiment contains the phosphorus-based flame retardant (E), the content thereof is preferably 10 parts by mass or more and 80 parts by mass or less, and more preferably 20 parts by mass or more and 70 parts by mass or less, relative to 100 parts by mass of the total of the polyphenylene ether compound (A) and the curing agent (C).

[0094] <Other Components> The resin composition according to the present embodiment may contain components (other components) other than the above-described components, as necessary, within a range that does not impair the effects of the present invention. Examples of other components contained in the resin composition according to the present embodiment include catalysts such as reaction initiators and reaction accelerators, polymerization inhibitors, polymerization retarders, free radical compounds, flame retardant aids, antifoaming agents, leveling agents, antioxidants, heat stabilizers, antistatic agents, UV absorbers, and additives such as dyes, pigments, dispersants, and lubricants.

[0095] As described above, the resin composition according to this embodiment may contain a reaction initiator (catalyst) and a reaction accelerator. The radical polymerization (curing) reaction of the resin composition may proceed even without a reaction initiator. However, depending on the process conditions, it may be difficult to raise the temperature high enough for curing to proceed, so a reaction initiator may be added. The reaction initiator and reaction accelerator are not particularly limited as long as they can accelerate the curing reaction of the resin composition. Specific examples include metal oxides, azo compounds, peroxides, imidazole compounds, phosphorus-based curing accelerators, and amine-based curing accelerators.

[0096] Specific examples of metal oxides include metal carboxylates. Examples of organic peroxides include α,α'-di(t-butylperoxy)diisopropylbenzene, 2,5-dimethyl-2,5-di(t-butylperoxy)-3-hexyne, benzoyl peroxide, 3,3',5,5'-tetramethyl-1,4-diphenoquinone, chloranil, 2,4,6-tri-t-butylphenoxyl, t-butylperoxyisopropyl monocarbonate, and azobisisobutyronitrile. Specific examples of azo compounds include 2,2'-azobis(2,4,4-trimethylpentane), 2,2'-azobis(N-butyl-2-methylpropionamide), and 2,2'-azobis(2-methylbutyronitrile). The above-mentioned reaction initiators may be used alone or in combination of two or more.

[0097] When the resin composition of the present embodiment contains the reaction initiator, its content is not particularly limited, but is preferably, for example, about 0.1 to 5.0 parts by mass per 100 parts by mass of the polyphenylene ether compound (A) and the curing agent (C) in total.

[0098] (Prepreg, Resin-Coated Film, Metal-Clad Laminate, Wiring Board, and Resin-Coated Metal Foil) Next, a prepreg for wiring boards, a metal-clad laminate, a wiring board, and a resin-coated metal foil using the resin composition of this embodiment will be described.

[0099] 1 is a schematic cross-sectional view showing an example of a prepreg 1 according to an embodiment of the present invention. In the following description, the respective reference numerals represent: 1 prepreg, 2 resin composition or semi-cured resin composition, 3 fibrous substrate, 11 metal-clad laminate, 12 insulating layer, 13 metal foil, 14 wiring, 21 wiring board, 31 resin-coated metal foil, 32, 42 resin layer, 41 resin-coated film, and 43 support film.

[0100] As shown in Fig. 1 , the prepreg 1 according to this embodiment comprises the resin composition or a semi-cured product of the resin composition 2, and a fibrous base material 3. Examples of this prepreg 1 include those in which the fibrous base material 3 is present in the resin composition or a semi-cured product thereof 2. That is, this prepreg 1 comprises the resin composition or a semi-cured product thereof, and the fibrous base material 3 present in the resin composition or a semi-cured product thereof 2.

[0101] In this embodiment, the term "semi-cured product" refers to a resin composition that has been partially cured to the extent that it can be further cured. That is, the semi-cured product is a resin composition that has been semi-cured (B-staged). For example, when a resin composition is heated, the viscosity initially gradually decreases, and then curing begins, and the viscosity gradually increases. In such a case, the semi-cured state can be exemplified by the state between when the viscosity starts to increase and when the composition is completely cured.

[0102] The prepreg obtained using the resin composition according to this embodiment may comprise a semi-cured product of the resin composition as described above, or may comprise the uncured resin composition itself. That is, it may be a prepreg comprising a semi-cured product of the resin composition (the resin composition in B stage) and a fibrous substrate, or a prepreg comprising the resin composition before curing (the resin composition in A stage) and a fibrous substrate. Specific examples include those in which a fibrous substrate is present in the resin composition. The resin composition or its semi-cured product may be obtained by heating and drying the resin composition.

[0103] The resin composition according to the present embodiment is often prepared in the form of a varnish and used as a resin varnish when producing the prepreg, or the resin-coated metal foil or metal-clad laminate described below. Such a resin varnish is prepared, for example, as follows.

[0104] First, each component soluble in an organic solvent, such as a resin component and a reaction initiator, is added to an organic solvent and dissolved. Heating may be performed as necessary. Then, an inorganic filler, such as silica filler (B), which is a component insoluble in an organic solvent, is added and dispersed using a ball mill, bead mill, planetary mixer, roll mill, or the like until a predetermined dispersion state is achieved, thereby preparing a varnish-like resin composition. The organic solvent used here is not particularly limited as long as it dissolves the resin components, such as the polyphenylene ether compound (A) and the curing agent (C), and does not inhibit the curing reaction. Specific examples include toluene, methyl ethyl ketone, cyclohexanone, cyclopentanone, methylcyclohexane, dimethylformamide, and propylene glycol monomethyl ether acetate. These may be used alone or in combination of two or more.

[0105] As a method for producing the prepreg 1 of this embodiment using the varnish-like resin composition of this embodiment, for example, a method of impregnating the fibrous base material 3 with the resin composition 2 in the form of a resin varnish and then drying it can be mentioned.

[0106] Specific examples of fibrous substrates used in producing prepregs include glass cloth, aramid cloth, polyester cloth, LCP (liquid crystal polymer) nonwoven fabric, glass nonwoven fabric, aramid nonwoven fabric, polyester nonwoven fabric, pulp paper, and linter paper. The use of glass cloth results in a laminate with excellent mechanical strength, and flattened glass cloth is particularly preferred. The glass cloth used in this embodiment is not particularly limited, but examples include low-dielectric-constant glass cloths such as E glass, S glass, NE glass, Q glass, and L glass. Flattening can be performed, for example, by continuously pressing the glass cloth with a press roll at an appropriate pressure to compress the yarns flat. The thickness of the fibrous substrate can generally be, for example, 0.01 to 0.3 mm.

[0107] The resin varnish (resin composition 2) is impregnated into the fibrous substrate 3 by immersion, coating, or the like. This impregnation can be repeated multiple times as necessary. In this case, it is also possible to repeat the impregnation using multiple resin varnishes with different compositions and concentrations, and to adjust the final composition (content ratio) and resin amount to the desired one.

[0108] The fibrous substrate 3 impregnated with the resin varnish (resin composition 2) is heated under desired heating conditions, for example, at a temperature of 80°C or higher and 180°C or lower for 1 minute or longer and 10 minutes or shorter. By heating, the solvent is volatilized from the varnish, reducing or removing the solvent, thereby obtaining a prepreg 1 in an uncured (A-stage) or semi-cured (B-stage) state.

[0109] 4, the resin-coated metal foil 31 of this embodiment has a configuration in which a resin layer 32 containing the above-mentioned resin composition or a semi-cured product of the resin composition is laminated with a metal foil 13. That is, the resin-coated metal foil of this embodiment may be a resin-coated metal foil comprising a resin layer containing the resin composition before curing (the resin composition in A stage) and a metal foil, or a resin-coated metal foil comprising a resin layer containing a semi-cured product of the resin composition (the resin composition in B stage) and a metal foil.

[0110] Examples of a method for producing such a resin-coated metal foil 31 include a method in which the resin composition in the form of a resin varnish as described above is applied to the surface of a metal foil 13 such as a copper foil, followed by drying. Examples of the application method include a bar coater, a comma coater, a die coater, a roll coater, a gravure coater, and the like.

[0111] As the metal foil 13, any metal foil that is used in metal-clad laminates, wiring boards, etc. can be used without any limitation, and examples thereof include copper foil and aluminum foil.

[0112] 5, the resin-coated film 41 of this embodiment has a configuration in which a resin layer 42 containing the above-mentioned resin composition or a semi-cured product of the resin composition is laminated on a film support substrate 43. That is, the resin-coated film of this embodiment may be a resin-coated film comprising the resin composition before curing (the resin composition in A stage) and a film support substrate, or may be a resin-coated film comprising a semi-cured product of the resin composition (the resin composition in B stage) and a film support substrate.

[0113] A method for producing such a resin-coated film 41 includes, for example, applying a resin varnish-like resin composition as described above to the surface of the film support substrate 43, and then evaporating the solvent from the varnish to reduce or remove the solvent, thereby obtaining a resin-coated film in a pre-cured (A stage) or semi-cured (B stage) state.

[0114] Examples of the film support substrate include electrically insulating films such as polyimide films, PET (polyethylene terephthalate) films, polyethylene naphthalate films, polyester films, polyparabanic acid films, polyether ether ketone films, polyphenylene sulfide films, aramid films, polycarbonate films, and polyarylate films.

[0115] In the resin-coated film and resin-coated metal foil of this embodiment, the resin composition or the semi-cured product thereof may be obtained by drying or heat-drying the resin composition, as in the prepreg described above.

[0116] The thickness of the metal foil 13 and the film support substrate 43 can be appropriately set depending on the desired purpose. For example, a metal foil 13 having a thickness of approximately 0.2 to 70 μm can be used. When the thickness of the metal foil is, for example, 10 μm or less, a carrier-attached copper foil having a release layer and a carrier for improved handling may be used. The resin varnish is applied to the metal foil 13 and the film support substrate 43 by coating, which can be repeated multiple times as needed. In addition, it is also possible to repeatedly apply multiple resin varnishes with different compositions and concentrations to adjust the final composition (content ratio) and resin amount to the desired level.

[0117] The drying or heating and drying conditions in the manufacturing method of the resin-coated metal foil 31 or the resin-coated film 41 are not particularly limited, but after applying a resin varnish-like resin composition to the metal foil 13 or the film support substrate 43, it is heated under the desired heating conditions, for example, at 50 to 180°C for about 0.1 to 10 minutes, to volatilize the solvent from the varnish and reduce or remove the solvent, thereby obtaining the resin-coated metal foil 31 or the resin-coated film 41 in a pre-cured (A stage) or semi-cured (B stage) state.

[0118] The resin-coated metal foil 31 or the resin-coated film 41 may be provided with a cover film or the like, as necessary. The provision of a cover film can prevent the inclusion of foreign matter, etc. The cover film is not particularly limited as long as it can be peeled off without damaging the shape of the resin composition. For example, a polyolefin film, a polyester film, a TPX film, a film formed by providing a release agent layer on any of these films, or even paper formed by laminating any of these films onto a paper substrate can be used.

[0119] 2, the metal-clad laminate 11 of this embodiment is characterized by having an insulating layer 12 containing a cured product of the above-described resin composition or a cured product of the above-described prepreg, and a metal foil 13. Note that the metal foil 13 used in the metal-clad laminate 11 may be the same as the metal foil 13 described above.

[0120] The metal-clad laminate 11 of this embodiment can also be produced using the resin-coated metal foil 31 or resin-coated film 41 described above.

[0121] A method for producing a metal-clad laminate using the prepreg 1, resin-coated metal foil 31, or resin-coated film 41 obtained as described above involves stacking one or more prepregs 1, resin-coated metal foils 31, or resin-coated films 41, and then stacking a metal foil 13 such as copper foil on both sides or one side of the prepreg 1, and then heat-pressure molding the stack to form an integrated laminate, thereby producing a double-sided or single-sided metal foil-clad laminate. The heat-pressure conditions can be set appropriately depending on the thickness of the laminate to be produced, the type of resin composition, and the like, but can be, for example, a temperature of 170 to 230°C, a pressure of 1.5 to 5.0 MPa, and a time of 60 to 150 minutes.

[0122] Alternatively, the metal-clad laminate 11 may be produced by forming a film-like resin composition on the metal foil 13 and then applying heat and pressure, without using the prepreg 1 or the like.

[0123] As shown in FIG. 3, the wiring board 21 of this embodiment has an insulating layer 12 containing the cured product of the resin composition or the cured product of the prepreg, and wiring 14 .

[0124] The resin composition of this embodiment is suitable for use as a material for the insulating layer of a wiring board. For example, a method for producing a wiring board 21 includes etching the metal foil 13 on the surface of the metal-clad laminate 11 obtained above to form a circuit (wiring), thereby obtaining a wiring board 21 having a conductor pattern (wiring 14) as a circuit on the surface of the laminate. In addition to the above-described methods, examples of the circuit formation method include circuit formation by a semi-additive process (SAP) or a modified semi-additive process (MSAP).

[0125] The prepreg, resin-coated film, and resin-coated metal foil obtained using the resin composition of this embodiment have excellent low dielectric properties and adhesion (particularly interlayer peel strength) when cured, making them very useful for industrial applications. Furthermore, metal-clad laminates and wiring boards obtained by curing them also have the same excellent properties.

[0126] This specification discloses various aspects of the technology as described above, but the main technologies among them are summarized below.

[0127] A resin composition according to a first aspect of the present invention comprises a polyphenylene ether compound (A) having a functional group containing a carbon-carbon unsaturated double bond, a silica filler (B), and a curing agent (C), wherein the silica filler (B) has an average particle size of 0.5 μm or more and 5.0 μm or less, which is obtained by arithmetically averaging the volume-based frequency distribution in the particle size distribution, and wherein, in the particle size distribution of the silica filler (B), when D10 is the volume-based cumulative 10% particle size, D50 is the volume-based cumulative 50% particle size, and D90 is the volume-based cumulative 90% particle size, at least one of a ratio V (D10 / D50) of D10 to D50 and a ratio W (D50 / D90) of D50 to D90 is 0.6 or more when the average particle size is less than 1.0 μm, and is 0.7 or more when the average particle size is 1.0 μm or more.

[0128] In the resin composition according to the second aspect of the present invention, the ratio (%) of the ratio V to the ratio W in the resin composition of the first aspect is 90% or more.

[0129] A resin composition according to a third aspect of the present invention is the resin composition according to the first or second aspect, wherein the functional group possessed by the polyphenylene ether compound (A) includes at least one selected from the functional groups represented by the formula (1) and the formula (2).

[0130] A resin composition according to a fourth aspect of the present invention is the resin composition according to any one of the first to third aspects, wherein the polyphenylene ether compound (A) comprises a polyphenylene ether compound (A-1) having 1 to 3 functional groups in the molecule.

[0131] A resin composition according to a fifth aspect of the present invention is the resin composition of any one of the first to fourth aspects, wherein the weight average molecular weight of the polyphenylene ether compound (A) is 500 to 5,000.

[0132] A resin composition according to a sixth aspect of the present invention is the resin composition according to any one of the first to fifth aspects, wherein the curing agent (C) contains at least one selected from the group consisting of a polyfunctional methacrylate compound, a polyfunctional acrylate compound, a polyfunctional alkenyl compound, and a polyfunctional maleimide compound, each having two or more reactive carbon-carbon unsaturated double bonds in the molecule.

[0133] A resin composition according to a seventh aspect of the present invention is the resin composition of any one of the first to sixth aspects, wherein the curing agent (C) further contains at least one selected from a polybutadiene compound having a number average molecular weight of 1,000 to 10,000, a butadiene-styrene copolymer, and an acrylate copolymer.

[0134] A resin composition according to an eighth aspect of the present invention is the resin composition of any one of the first to seventh aspects, wherein the content of the silica filler (B) is 10 parts by mass or more and 400 parts by mass or less relative to 100 parts by mass of the total of the polyphenylene ether compound (A) and the curing agent (C).

[0135] A resin composition according to a ninth aspect of the present invention is the resin composition of any one of the first to eighth aspects, wherein the content of the polyphenylene ether compound (A) is 30% by mass or more and 80% by mass or less, relative to 100% by mass of the total of the polyphenylene ether compound (A) and the curing agent (C).

[0136] A resin composition according to a tenth aspect of the present invention is the resin composition of any one of the first to ninth aspects, wherein the content of the curing agent (C) is 20% by mass or more and 70% by mass or less, relative to 100% by mass of the total of the polyphenylene ether compound (A) and the curing agent (C).

[0137] A resin composition according to an eleventh aspect of the present invention is the resin composition according to any one of the first to tenth aspects, further comprising a silane coupling agent (D) having a functional group containing a carbon-carbon unsaturated bond.

[0138] A resin composition according to a twelfth aspect of the present invention is the resin composition according to any one of the first to eleventh aspects, which contains a phosphorus-based flame retardant (E) having a melting point of 280°C or higher and having two or more diphenylphosphine oxide groups in the molecule.

[0139] A prepreg according to a thirteenth aspect of the present invention comprises the resin composition of any one of the first to twelfth aspects or a semi-cured product of the resin composition, and a fibrous base material.

[0140] A resin-coated film according to a fourteenth aspect of the present invention comprises a resin layer containing the resin composition of any one of the first to twelfth aspects or a semi-cured product of the resin composition, and a support film.

[0141] A resin-coated metal foil according to a fifteenth aspect of the present invention comprises a resin layer containing the resin composition of any one of the first to twelfth aspects or a semi-cured product of the resin composition, and a metal foil.

[0142] A metal-clad laminate according to a sixteenth aspect of the present invention has an insulating layer containing a cured product of the resin composition according to any one of the first to twelfth aspects or a cured product of the prepreg according to the thirteenth aspect, and a metal foil.

[0143] A wiring board according to a seventeenth aspect of the present invention has an insulating layer including a cured product of the resin composition according to any one of the first to twelfth aspects or a cured product of the prepreg according to the thirteenth aspect, and wiring.

[0144] The present invention will be explained in more detail below with reference to examples, but the scope of the present invention is not limited to these examples.

[0145] First, the components used in preparing the resin composition in this example will be described.

[0146] <Polyphenylene ether compound (A-1)> Modified PPE1: polyphenylene ether compound having a methacryloyl group at the end ("SA9000" manufactured by SABIC Innovative Plastics, a modified polyphenylene ether in which the terminal hydroxyl group of polyphenylene ether is modified with a methacryloyl group, weight average molecular weight Mw 2000)

[0147] Modified PPE2 is a modified polyphenylene ether obtained by reacting polyphenylene ether with chloromethylstyrene. Specifically, it is a modified polyphenylene ether obtained by the following reaction.

[0148] First, 200 g of polyphenylene ether (SA90 manufactured by SABIC Innovative Plastics, 2 terminal hydroxyl groups, weight average molecular weight Mw 1700), 30 g of a 50:50 mass ratio mixture of p-chloromethylstyrene and m-chloromethylstyrene (chloromethylstyrene: CMS manufactured by Tokyo Chemical Industry Co., Ltd.), 1.227 g of tetra-n-butylammonium bromide as a phase transfer catalyst, and 400 g of toluene were charged into a 1-liter three-neck flask equipped with a temperature controller, a stirrer, a cooling device, and a dropping funnel, and the mixture was stirred. The polyphenylene ether, chloromethylstyrene, and tetra-n-butylammonium bromide were stirred until they were dissolved in toluene. The mixture was gradually heated, and finally heated until the liquid temperature reached 75 ° C. Then, an aqueous sodium hydroxide solution (20 g sodium hydroxide / 20 g water) was added dropwise to the solution as an alkali metal hydroxide over 20 minutes. The mixture was then stirred at 75°C for an additional 4 hours. Next, the contents of the flask were neutralized with 10% by mass hydrochloric acid, and a large amount of methanol was added. This caused a precipitate to form in the liquid in the flask. That is, the product contained in the reaction solution in the flask was reprecipitated. The precipitate was then filtered, washed three times with a mixture of methanol and water in a mass ratio of 80:20, and then dried under reduced pressure at 80°C for 3 hours.

[0149] The obtained solid is １ H-NMR (400MHz, CDCl ３, TMS). As a result of NMR measurement, a peak derived from a vinylbenzyl group (ethenylbenzyl group) was confirmed at 5 to 7 ppm. This confirmed that the obtained solid was a modified polyphenylene ether compound having a vinylbenzyl group (ethenylbenzyl group) as the substituent at the molecular end in the molecule. Specifically, it was confirmed that it was an ethenylbenzylated polyphenylene ether. The obtained modified polyphenylene ether compound was represented by the above formula (14), in which Y is a dimethylmethylene group (represented by formula (12), and R in formula (12) ３３ and R ３４ is a methyl group), Z is a phenylene group, and R １ The compound was a modified polyphenylene ether compound in which R3 was a hydrogen atom and n was 1.

[0150] The number of terminal functional groups of the modified polyphenylene ether was measured as follows. First, the modified polyphenylene ether was accurately weighed. The weight at that time was designated X (mg). The weighed modified polyphenylene ether was then dissolved in 25 mL of methylene chloride, and 100 μL of a 10 mass% ethanol solution of tetraethylammonium hydroxide (TEAH) (TEAH:ethanol (volume ratio) = 15:85) was added to the solution. The absorbance (Abs) at 318 nm was then measured using a UV spectrophotometer (UV-1600, manufactured by Shimadzu Corporation). The number of terminal hydroxyl groups of the modified polyphenylene ether was then calculated from the measurement results using the following formula:

[0151] Residual OH amount (μmol / g) = [(25×Abs) / (ε×OPL×X)]×10 ６ Here, ε is the extinction coefficient and is 4700 L / mol·cm, and OPL is the cell optical path length and is 1 cm.

[0152] The calculated residual OH amount (number of terminal hydroxyl groups) of the modified polyphenylene ether was almost zero, which indicated that the hydroxyl groups of the polyphenylene ether before modification were almost entirely modified. This indicated that the decrease from the number of terminal hydroxyl groups of the polyphenylene ether before modification was the number of terminal hydroxyl groups of the polyphenylene ether before modification. In other words, it was found that the number of terminal hydroxyl groups of the polyphenylene ether before modification was the number of terminal functional groups of the modified polyphenylene ether. In other words, the number of terminal functional groups was two.

[0153] The molecular weight distribution of the modified polyphenylene ether was measured by GPC. The weight average molecular weight (Mw) was calculated from the molecular weight distribution. The Mw was found to be 1,900.

[0154] <Silica Filler (B)> Silica Filler 1 (manufactured by Zhejiang Sanshiji New Materials Technology Co., Ltd., "EQ0610-SMC") Silica Filler 2 (manufactured by Zhejiang Sanshiji New Materials Technology Co., Ltd., "EQ2410-SMC") Silica Filler 3 (manufactured by Zhejiang Sanshiji New Materials Technology Co., Ltd., "EQ5010-SMC") Silica Filler 4 (vinylsilane-treated spherical silica, silica particles "SC2300-SVJ" manufactured by Admatechs Co., Ltd.) Silica Filler 5 (manufactured by Zhejiang Sanshiji New Materials Technology Co., Ltd., "VF02510-SM")

[0155] <Curing Agent (C)> Curing agent 1: allyl compound (triallyl isocyanurate ("TAIC" manufactured by Nippon Chemical Industry Co., Ltd.)) Curing agent 2: polybutadiene oligomer ("B-1000" manufactured by Nippon Soda Co., Ltd., number average molecular weight 1200)

[0156] <Silane Coupling Agent (D)> Silane coupling agent: 3-methacryloxypropyltrimethoxysilane (a silane coupling agent having a methacryl group in the molecule, "KBM-503" manufactured by Shin-Etsu Chemical Co., Ltd.)

[0157] <Phosphorus-based flame retardant (E)> Phosphorus-based flame retardant: diphenylphosphine oxide compound, manufactured by Shinichi Chemical Co., Ltd., "PQ60"

[0158] <Reaction initiator> Peroxide 1: α,α'-di(t-butylperoxy)diisopropylbenzene ("Perbutyl P (PBP)" manufactured by NOF Corporation)

[0159] Examples 1 to 5 and Comparative Examples 1 and 2 [Preparation Method] (Resin Varnish) First, the resin components were added to a solvent (toluene) at the blending ratios (parts by mass) shown in Table 2 below, and mixed to a solids concentration of 100% by mass. The resulting mixture was stirred for 60 minutes. Thereafter, an inorganic filler (silica filler) was added to the resulting mixture, and after pre-dispersion using a stirrer, the filler was dispersed using a bead mill. This resulted in a varnish-like resin composition (varnish).

[0160] (Preparation of Evaluation Board) A prepreg and an evaluation board (metal-clad laminate) were obtained as follows.

[0161] First, a fibrous substrate (glass cloth: #1078 type, L2 glass manufactured by Asahi Kasei Corporation) was impregnated with the obtained varnish, and then heated and dried at 120°C for 3 minutes to produce a resin prepreg with a thickness of 125 μm. At this time, the content of the components constituting the resin composition by the curing reaction relative to the prepreg (resin content) was adjusted to be approximately 56 mass%.

[0162] Next, an evaluation substrate (metal-clad laminate) was obtained as follows.

[0163] Two or six of the resulting prepregs were stacked, and copper foil (NANYA PLASTICS CORP. "TLCV1" copper foil thickness: 18 μm) was placed on both sides. This was used as a pressure body, and heated to 210°C at a temperature increase rate of 3°C / min, and then heated and pressurized at 210°C for 90 minutes under a pressure of 3 MPa, to obtain an evaluation substrate (metal-clad laminate) with copper foil bonded to both sides and a resin layer thickness of approximately 750 μm.

[0164] Using the evaluation substrate (metal-clad laminate) prepared as described above, an evaluation test was carried out by the following method.

[0165] <Evaluation Test 1> [Particle Size Distribution of Silica Filler] First, the particle size distribution of the silica filler used in each example and comparative example was determined by measurement using a laser diffraction / scattering particle size distribution measuring device LA-960V2 (manufactured by Horiba, Ltd.). The specifications of the device are as follows: Measurement principle: Mie scattering theory Measurement method: Flow measurement Measurement range: 0.01 μm to 5000 μm Light source: LD (650 nm), approximately 5 mW, LED (405 mm), approximately 3 mW Detector: 1 ring-shaped 64-segment silicon photodiode, 5 4-channel array detectors, 3 silicon photodetectors Refractive index: 1.460-0.000i

[0166] The specifications of the measurement unit (circulation system) are as follows: Dispersion: ultrasonic probe Circulation: centrifugal pump Mixing: rotor Flow cell material: synthetic quartz

[0167] The particle size distribution measurement conditions are as follows.

[0168] Each measurement sample was placed in a flow cell via a sample bath using toluene as a dispersion solvent, and laser diffraction / scattering particle size distribution measurement was carried out in a stirred state.

[0169] The particle size distribution was analyzed and calculated using the analytical software LA-960 for Windows attached to the LA-960V2, and the D50 and D90 of each were determined.

[0170] [Average Particle Size of Silica Filler] The average particle size of each silica filler was measured using the above-mentioned LA-960V2.

[0171] The results are shown in Table 1.

[0172]

[0173] (Dielectric Property 1: Dielectric Loss Tangent (Df)) An unclad plate obtained by etching the copper foil from the 750 μm thick evaluation substrate (metal-clad laminate) was used as a test specimen, and the relative permittivity and dielectric loss tangent at 10 GHz were measured using a cavity resonator perturbation method. Specifically, the dielectric loss tangent of the evaluation substrate at 10 GHz was measured using a network analyzer (N5230A manufactured by Keysight Technologies, Inc.). In this test, a Df of 0.00265 or less was considered to be pass.

[0174] (Dielectric Property 2: Dielectric Loss Tangent (Df) After Drying) After drying the test piece at 105° C. for 2 hours, the dielectric loss tangent of the evaluation substrate at 10 GHz was measured in the same manner as above. In this test, a Df of 0.00220 or less was considered to be a pass.

[0175] (Interlayer Peel Strength) The insulating layer (prepreg) on ​​the top surface of the evaluation substrate (metal-clad laminate) was peeled off at a rate of 50 mm / min using a tensile tester (i.e., the insulating layer on the top surface was peeled off from the insulating layer underneath), and the peel strength (N / mm ２ The peel strength is the interlayer peel strength. The higher the peel strength, the higher the interlayer adhesion. When the measured interlayer peel strength was 0.4 N / mm ２ If it was above that, it was considered a pass.

[0176] The results are shown in Table 2.

[0177]

[0178] (Discussion) As is clear from the results shown in Table 2, it was confirmed that the resin composition of the present invention can provide a cured product having low dielectric properties (Df) and excellent interlayer peel strength (adhesion). In contrast, Comparative Examples 1 and 2, which used a resin composition containing a silica filler that does not satisfy the requirements of the present invention, resulted in poor results in at least one of low dielectric properties and interlayer peel strength.

[0179] <Evaluation Test 2> The evaluation boards of Examples 1 to 5 were further subjected to the following test.

[0180] (Dielectric Property 3: Dielectric Constant (Dk)) An unclad board obtained by removing the copper foil from an evaluation substrate (metal-clad laminate) by etching was used as a test specimen, and the dielectric constant and dielectric loss tangent at 10 GHz were measured using a cavity resonator perturbation method. Specifically, the dielectric constant of the evaluation substrate at 10 GHz was measured using a network analyzer (N5230A manufactured by Keysight Technologies, Inc.). In this test, a Dk of 3.50 or less was considered to be pass.

[0181] (Copper Foil Peel Strength) The copper foil was peeled off from the evaluation substrate (metal-clad laminate), and the peel strength at this time was measured in accordance with JIS C 6481 (1996). Specifically, the evaluation substrate was set to a width and length of 10 mm, and the copper foil was peeled off at a rate of 50 mm / min using a tensile tester, and the peel strength at this time (N / mm ２ This peel strength is the copper foil peel strength, and it is understood that the higher this is, the higher the adhesion of the metal foil (copper foil). In this test, the copper foil peel strength measured was 0.4 N / mm ２ If it was above that, it was considered a pass.

[0182] The results are shown in Table 3.

[0183]

[0184] (Discussion) From the results in Table 3, it was confirmed that in the Examples using the resin compositions of the present invention, in addition to the results of Evaluation Test 1, they also had excellent low dielectric properties (Dk) and copper foil peel strength.

[0185] This application is based on Japanese Patent Application No. 2023-222739, filed on December 28, 2023, the contents of which are incorporated herein by reference.

[0186] In order to express the present invention, the present invention has been properly and sufficiently described above through embodiments with reference to specific examples, drawings, etc., but it should be recognized that those skilled in the art can easily make changes and / or improvements to the above-described embodiments. Therefore, unless changes or improvements made by those skilled in the art deviate from the scope of the claims set forth in the claims, such changes or improvements are construed as being encompassed within the scope of the claims.

[0187] The present invention has wide industrial applicability in technical fields related to electronic materials, electronic devices, optical devices, and the like.

Claims

1. A resin composition comprising a polyphenylene ether compound (A) having a functional group containing a carbon-carbon unsaturated double bond, a silica filler (B), and a curing agent (C), wherein the silica filler (B) has an average particle diameter obtained by arithmetically averaging the frequency distribution based on volume in the particle size distribution of 0.5 μm or more and 5.0 μm or less, and when the cumulative 10% particle diameter based on volume in the particle size distribution of the silica filler (B) is D10, the cumulative 50% particle diameter based on volume is D50, and the cumulative 90% particle diameter based on volume is D90, at least one of the ratio V (D10 / D50) of D10 to D50 and the ratio W (D50 / D90) of D50 to D90 is 0.6 or more when the average particle diameter is less than 1.0 μm and 0.7 or more when the average particle diameter is 1.0 μm or more.

2. The resin composition according to claim 1, wherein the ratio (%) of the ratio V to the ratio W is 90% or more.

3. The resin composition according to claim 1, wherein the functional group of the polyphenylene ether compound (A) contains at least one selected from the functional groups represented by formula (1) and formula (2). (In formula (1), s represents an integer of 0 to 10. Z represents an arylene group. R １ ~R ３ each independently represents a hydrogen atom or an alkyl group.) (In formula (2), R ４ represents a hydrogen atom or an alkyl group.) 4. The resin composition according to claim 1, wherein the polyphenylene ether compound (A) contains a polyphenylene ether compound (A-1) having 1 to 3 of the functional groups in the molecule.

5. The resin composition according to claim 1, wherein the weight average molecular weight of the polyphenylene ether compound (A) is 500 to 5000.

6. The resin composition according to claim 1, wherein the curing agent (C) contains at least one selected from the group consisting of a polyfunctional methacrylate compound, a polyfunctional acrylate compound, a polyfunctional alkenyl compound, and a polyfunctional maleimide compound having 2 or more reactive carbon-carbon unsaturated double bonds in the molecule.

7. The resin composition according to claim 6, wherein the curing agent (C) further contains at least one selected from the group consisting of a polybutadiene compound, a butadiene-styrene copolymer, and an acrylate copolymer having a number average molecular weight of 1000 to 10000.

8. The resin composition according to claim 1, wherein the content of the silica filler (B) is 40 parts by mass or more and 400 parts by mass or less with respect to 100 parts by mass in total of the polyphenylene ether compound (A) and the curing agent (C).

9. The resin composition according to claim 1, wherein the content of the polyphenylene ether compound (A) is 30% by mass or more and 80% by mass or less with respect to 100% by mass in total of the polyphenylene ether compound (A) and the curing agent (C).

10. The resin composition according to claim 1, wherein the content of the curing agent (C) is 20% by mass or more and 70% by mass or less based on 100% by mass of the total of the polyphenylene ether compound (A) and the curing agent (C).

11. The resin composition according to claim 1, which contains a silane coupling agent (D) having a functional group containing a carbon-carbon unsaturated bond.

12. The resin composition according to claim 1, which contains a phosphorus-based flame retardant (E) having a melting point of 280°C or higher and having two or more diphenylphosphine oxide groups in the molecule.

13. A prepreg having the resin composition according to any one of claims 1 to 12 or a semi-cured product of the resin composition and a fibrous substrate.

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

15. A metal-clad laminate having a resin layer containing the resin composition according to any one of claims 1 to 12 or a semi-cured product of the resin composition and a metal foil.

16. A metal-clad laminate having an insulating layer containing a cured product of the resin composition according to any one of claims 1 to 12 and a metal foil.

17. A wiring board having an insulating layer containing a cured product of the resin composition according to any one of claims 1 to 12 and a wiring.

18. A metal-clad laminate having an insulating layer containing a cured product of the prepreg according to claim 13 and a metal foil.

19. A wiring board having an insulating layer containing a cured product of the prepreg according to claim 13 and a wiring.

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