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

Abstract

The present invention provides a resin composition that allows for the production of a cured product possessing properties such as low dielectric properties and heat resistance, while also having sufficient toughness to withstand etching. [Solution] A resin composition is provided comprising a polyphenylene ether compound having at least one of an aromatic vinyl group and a (meth)acrylic group, and an allyl compound represented by formula (3), wherein the cured product has a dielectric loss tangent of 0.0016 or less at 10 GHz. JPEG2026067886000040.jpg3873 (In formula (3), R A (This represents an alkyl or alkenyl group having 8 to 22 carbon atoms.)

Description

[Technical Field]

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

[0002] In recent years, with the increasing amount of information processing required for various electronic devices, mounting technologies such as the high integration of semiconductor devices, high density of wiring, and multilayering have been rapidly advancing. Substrate materials used to form the base material of wiring boards in various electronic devices require low dielectric constant and dielectric loss tangent in order to increase signal transmission speed and reduce signal loss during transmission.

[0003] Polyphenylene ether (PPE) is known to have excellent dielectric properties, such as low dielectric constant and dielectric loss tangent, and maintains these properties even in high-frequency ranges (high-frequency regions) from the MHz to GHz bands. For this reason, polyphenylene ether is being considered for use as a molding material for high-frequency applications. More specifically, it is preferably used as a substrate material for constructing the base material of wiring boards used in electronic devices that utilize high-frequency bands.

[0004] For example, Patent Document 1 discloses a resin composition comprising a modified polyphenylene ether compound and a crosslinking curing agent having a carbon-carbon unsaturated double bond, such as triallyl isocyanurate (TAIC) or divinylbenzene. According to a resin composition like the one disclosed in Patent Document 1, it is possible to provide a cured product with low dielectric constant, low dielectric loss tangent, and excellent heat resistance.

[0005] The resin composition described in Patent Document 1 is an excellent resin composition from the viewpoints of low dielectric characteristics and heat resistance. However, according to the research of the present inventors, when an insulating layer containing a cured product of a resin composition containing a crosslinking type curing agent as described above and a copper-clad laminate having metal foils on both sides of the insulating layer are used, it has been found that the crosslink density increases with the three-dimensional crosslinkability of the resin. As the crosslink density increases, it is considered that the toughness of the resin is insufficient. For example, when a resin composition not containing a glass cloth is cured, problems such as cracking during an etching process for forming wiring or the like occur.

[0006] From the above, there has been a demand for the development of a resin composition capable of obtaining a cured product having toughness enough to withstand an etching process while having characteristics such as low dielectric characteristics and heat resistance.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Summary of the Invention

[0008] The present invention has been made in view of such circumstances, and an object thereof is to provide a resin composition capable of improving the toughness and handling property of a cured product while maintaining characteristics such as low dielectric characteristics and high Tg. Another object is to provide a prepreg, a film with resin, a metal foil with resin, a metal-clad laminate, and a wiring board using the resin composition.

[0009] The resin composition according to one aspect of the present invention contains a polyphenylene ether compound having at least one of the groups represented by the following formula (1) and formula (2), and an allyl compound represented by the following formula (3), and in its cured product, the dielectric tangent at 10 GHz is 0.0016 or less.

[0010]

Chemical Formula

[0011]

Chemical formula

[0012]

Chemical formula

Brief description of the drawings

[0013] [Figure 1] Figure 1 is a schematic cross-sectional view showing the configuration of a prepreg according to an embodiment of the present invention. [Figure 2] Figure 2 is a schematic cross-sectional view showing the configuration of a metal-clad laminate according to an embodiment of the present invention. [Figure 3] Figure 3 is a schematic cross-sectional view showing the configuration of a wiring board according to an embodiment of the present invention. [Figure 4] Figure 4 is a schematic cross-sectional view showing the configuration of a metal foil with resin according to an embodiment of the present invention. [Figure 5] Figure 5 is a schematic cross-sectional view showing the configuration of a resin film according to an embodiment of the present invention.

Modes for carrying out the invention

[0014] The resin composition according to an embodiment of the present invention (hereinafter, also simply referred to as the resin composition) is characterized by containing a polyphenylene ether compound having at least one of the groups represented by the above formula (1) and formula (2), and an allyl compound represented by the above formula (3).

[0015] By including the allyl compound in addition to the polyphenylene ether compound, it is possible to provide a resin composition that exhibits not only low dielectric properties and high Tg (glass transition temperature), but also excellent handling properties and toughness in its cured product. This is thought to be because the allyl compound can suppress, to some extent, the increase in crosslink density due to the three-dimensional crosslinking properties of the resin.

[0016] In other words, according to the present invention, it is possible to provide a resin composition that has low dielectric properties and can improve the toughness and handling properties of the cured product while maintaining excellent properties such as high Tg. Furthermore, by using the resin composition, it is possible to provide prepregs, resin-coated films, resin-coated metal foils, metal-clad laminates, and wiring boards that have high toughness and excellent handling properties, as well as properties such as low dielectric properties and high Tg.

[0017] Furthermore, as a material property, materials with a high Tg of cured material exhibit improved heat resistance (solder heat resistance, etc.). In addition, a high Tg of cured material has the advantage of a smaller coefficient of thermal expansion at higher temperatures. Generally, thermal expansion increases rapidly at temperatures above the glass transition temperature. In other words, a low glass transition temperature results in a large coefficient of thermal expansion at temperatures above that temperature. A low glass transition temperature leads to increased thermal expansion at higher temperatures, which can worsen the reliability of interlayer connections in printed circuit boards (e.g., barrel cracking in through-holes), potentially rendering the board unusable. This is thought to be because the difference in coefficients of thermal expansion at high temperatures between the insulating layer, which is made of cured resin material within the substrate, and the through-holes, which are made of metal, increases, causing cracks to form on the walls of the metal through-holes and reducing connection reliability.

[0018] Below, we will first describe in detail each component of the resin composition according to this embodiment.

[0019] <Polyphenylene ether compounds> The polyphenylene ether compound used in this embodiment is a modified polyphenylene ether compound that exhibits excellent low dielectric properties when cured, and is not particularly limited as long as it is a polyphenylene ether compound having at least one of the groups represented by the following formulas (1) and (2). It is believed that by including such a modified polyphenylene ether compound, a resin composition can be obtained in which a cured product with low dielectric properties and high heat resistance can be obtained.

[0020] [ka]

[0021] In formula (1), p represents an integer between 0 and 10. Z represents an arylene group. R1 to R3 are independent of each other; that is, R1 to R3 may be the same group or different groups. R1 to R3 represent a hydrogen atom or an alkyl group.

[0022] In equation (1), if s is 0, it indicates that Z is directly bonded to the end of the polyphenylene ether.

[0023] The arylene group Z described above is not particularly limited. Examples of this arylene group include monocyclic aromatic groups such as phenylene groups, and polycyclic aromatic groups in which the aromatic element is not monocyclic but polycyclic, such as naphthalene rings. Furthermore, this 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. The alkyl group is not particularly limited, 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.

[0024] [ka]

[0025] In formula (2), R4 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.

[0026] Preferred specific examples of substituents represented by formula (1) include, for example, substituents containing a vinylbenzyl group. Examples of substituents containing a vinylbenzyl group include substituents represented by the following formula (4). Examples of substituents represented by formula (2) include acrylate groups and methacrylate groups.

[0027] [ka]

[0028] More specifically, examples of the substituents include vinyl benzyl groups (ethenyl benzyl groups) such as p-ethenylbenzyl groups and m-ethenylbenzyl groups, vinylphenyl groups, acrylate groups, and methacrylate groups.

[0029] The polyphenylene ether compound has a polyphenylene ether chain in its molecule, and preferably has a repeating unit represented by the following formula (5) in its molecule.

[0030] [ka]

[0031] In formula (5), t represents a value between 1 and 50. Furthermore, R5 to R8 are independent of each other. That is, R5 to R8 may be the same group or different groups. Also, R5 to R8 represent 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.

[0032] In R5 to R8, the functional groups listed are specifically as follows:

[0033] 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.

[0034] 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.

[0035] 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).

[0036] 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.

[0037] 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.

[0038] 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.

[0039] The weight-average molecular weight (Mw) of the polyphenylene ether compound is not particularly limited. Specifically, it is preferably 500 to 5000, more preferably 800 to 4000, and even more preferably 1000 to 3000. Here, the weight-average molecular weight can be measured by any 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 (5) in its molecule, it is preferable that t is a value such that the weight-average molecular weight of the polyphenylene ether compound falls within this range. Specifically, it is preferable that t is 1 to 50.

[0040] When the weight-average molecular weight of the polyphenylene ether compound is within this 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 is within this range, the molecular weight is relatively low, so the heat resistance of the cured product tends to decrease. In this respect, the polyphenylene ether compound according to this embodiment has one or more unsaturated double bonds at its terminals, so it is thought that a cured product with sufficiently high heat resistance can be obtained. Furthermore, when the weight-average molecular weight of the polyphenylene ether compound is within this 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.

[0041] The average number of substituents (terminal functional groups) at the molecular ends of each molecule of the polyphenylene ether compound is not particularly limited. Specifically, it is preferably 1 to 5, more preferably 1 to 3, and even 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. On the other hand, if the number of terminal functional groups is too large, the reactivity becomes too high, which may lead to problems such as a decrease in the shelf life of the resin composition or a decrease in the fluidity of the resin composition. In other words, using such a polyphenylene ether compound may result in molding defects such as voids occurring during multilayer molding due to insufficient fluidity, making it difficult to obtain a highly reliable printed circuit board.

[0042] The number of terminal functional groups in a polyphenylene ether compound can be expressed as a numerical value representing the average number of substituents per molecule of the modified polyphenylene ether compound present in 1 mole of the polyphenylene ether compound. This 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 decrease from the number of hydroxyl groups in the polyphenylene ether before modification. This decrease 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.

[0043] The intrinsic viscosity of the polyphenylene ether compound in this embodiment is not particularly limited. Specifically, it is preferably 0.03 to 0.12 dl / g, more preferably 0.04 to 0.11 dl / g, and even more preferably 0.06 to 0.095 dl / g. If the intrinsic viscosity is too low, the molecular weight tends to be low, making it difficult to obtain low dielectric properties such as low dielectric constant and low dielectric loss tangent. On the other hand, if the intrinsic viscosity is too high, the viscosity is high, sufficient fluidity cannot be obtained, and the moldability of the cured product tends to decrease. Therefore, if the intrinsic viscosity of the polyphenylene ether compound is within the above range, excellent heat resistance and moldability can be achieved in the cured product.

[0044] The intrinsic viscosity referred to here is the intrinsic viscosity measured in methylene chloride at 25°C. More specifically, it is the value measured using a viscometer in a 0.18 g / 45 ml methylene chloride solution (at a liquid temperature of 25°C). Examples of such viscometers include the Schott AVS500 Visco System.

[0045] Examples of the polyphenylene ether compound of the present embodiment include modified polyphenylene ether compounds represented by the following formulas (6) to (8). Further, as the polyphenylene ether compound of the present embodiment, these modified polyphenylene ether compounds may be used alone or in combination.

[0046]

Chemical formula

[0047]

Chemical formula

[0048]

Chemical formula

[0049] In formulas (6) to (8), R9 to R 16 , R 17 to R 24 and R 25 to R 28 are each independent. That is, R9 to R 16 , R 17 to R 24 and R 25 to R 28 may be the same group or different groups. R9 to R 16 , R 17 to R 24 and R 25 to R 28 represent 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.

[0050] Further, in the above formula (8), s represents an integer of 1 to 100.

[0051] The above R9 to R 16 , R 17 to R 24R 25 ~R 28 Specifically, the functional groups mentioned above include the following:

[0052] 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.

[0053] Furthermore, 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.

[0054] Furthermore, 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).

[0055] Furthermore, 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.

[0056] Furthermore, 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.

[0057] Furthermore, 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.

[0058] Furthermore, in formulas (6) and (8) above, A and B represent repeating units represented by the following formulas (9) and (10), respectively. Also, in formula (7), Y represents a linear, branched, or cyclic hydrocarbon having 20 or fewer carbon atoms.

[0059] [ka]

[0060] [ka]

[0061] In equations (9) and (10), m and n each represent values ​​from 0 to 20. 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 ​​from 0 to 20, n represents values ​​from 0 to 20, and the sum of m and n is between 1 and 30.

[0062] Furthermore, in equations (9) and (10), R 29 ~R 32 R 33 ~R 36 These are independent of each other, R 29 ~R 32 R 33 ~R 36 These may be the same group or different groups, and represent 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.

[0063] In formula (7) above, Y is a linear, branched, or cyclic hydrocarbon having 20 or fewer carbon atoms, as described above. Examples of Y include the group represented by the following formula (11).

[0064] [ka]

[0065] In equation (11) above, R 37 and R 38 Each of these independently represents either a hydrogen atom or an alkyl group. Examples of the alkyl group include a methyl group. Examples of the group represented by formula (11) include a methylene group, a methylmethylene group, and a dimethylmethylene group, among which the dimethylmethylene group is preferred.

[0066] In formulas (6) to (8), X1 to X3 each independently represent the substituent represented by formula (1) and / or the substituent represented by formula (2). In the modified polyphenylene ether compounds represented by formulas (6) to (8), X1 to X3 may be the same substituent or different substituents.

[0067] More specific examples of the modified polyphenylene ether compound represented by formula (6) include, for example, the modified polyphenylene ether compound represented by the following formula (12).

[0068] [ka]

[0069] More specific examples of the modified polyphenylene ether compound represented by formula (7) include, for example, the modified polyphenylene ether compound represented by the following formula (13) and the modified polyphenylene ether compound represented by the following formula (14).

[0070] [ka]

[0071] [ka]

[0072] In equations (12) to (14) above, m and n are the same as m and n in equations (9) and (10) above. Also, in equations (12) and (13) above, R1 to R3, p and Z are the same as R1 to R3, p and Z in equation (1), respectively. Also, in equations (13) and (14) above, Y is the same as Y in equation (7) above. Also, in equation (14) above, R4 is the same as R4 in equation (2) above.

[0073] 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 that has been terminally modified by the group represented by formula (1) and / or formula (2). Specifically, examples include reacting a polyphenylene ether with a compound in which a substituent having a carbon-carbon unsaturated double bond and a halogen atom are bonded.

[0074] 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 (1), (2), and (5) is bonded to a halogen atom. Specifically, examples of the halogen atom include chlorine, bromine, iodine, and fluorine atoms, with chlorine 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 p-chloromethylstyrene and m-chloromethylstyrene.

[0075] The raw material, polyphenylene ether, is not particularly limited as long as it can ultimately synthesize the desired modified 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.

[0076] The method for synthesizing the polyphenylene ether compound of this embodiment is as described above. Specifically, the polyphenylene ether described above and a 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 a 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.

[0077] 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 a substituent having a carbon-carbon unsaturated double bond is bonded to a halogen atom. 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.

[0078] 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.

[0079] The reaction conditions, such as reaction time and reaction temperature, vary depending on the compound, such as the substituent having a carbon-carbon unsaturated double bond bonded to a halogen atom, and are not particularly limited as long as the above-mentioned reaction proceeds 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.

[0080] The solvent used in the reaction is not particularly limited, as long as it can dissolve the polyphenylene ether and the compound having a substituent with a carbon-carbon unsaturated double bond bonded to a halogen atom, and does not inhibit the reaction between the polyphenylene ether and the compound having a substituent with a carbon-carbon unsaturated double bond bonded to a halogen atom. Specifically, examples include toluene.

[0081] 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.

[0082] The phase transfer catalyst is not particularly limited, but examples include quaternary ammonium salts such as tetra-n-butylammonium bromide.

[0083] The resin composition used in this embodiment preferably contains, as the polyphenylene ether compound, the modified polyphenylene ether compound obtained as described above.

[0084] <Allyl compounds> The allyl compound in this embodiment serves as a so-called curing agent and can be used without particular limitation as long as it is represented by the following formula (3).

[0085] [ka]

[0086] In formula (3), R A This represents an alkyl or alkenyl group having 8 to 22 carbon atoms. By using the allyl compound having such an alkyl or alkenyl group with such a number of carbon atoms, it is possible to provide a resin composition that can produce a cured product with excellent crosslinking properties and high toughness. As a result, even if the resin composition does not contain a substrate such as glass cloth, cracking during etching or other processes can be suppressed.

[0087] From the viewpoint of improving handling properties, the number of carbon atoms is more preferably 12 or more and more preferably 18 or less. This is thought to improve the resin flowability of the resin composition, and to result in superior circuit filling properties when using the resin composition of this embodiment to create multilayer circuit boards and the like.

[0088] In preferred embodiments, it is desirable that the equivalent amount of the reactive group (allyl group) in the allyl compound is 1000 or less. It is believed that a high Tg can be obtained more reliably if the equivalent amount is 1000 or less.

[0089] Examples of the C8-C22 alkyl group include linear or branched alkyl groups, such as octyl, nonyl, decyl, dodecyl, tetradecyl, hexadecyl, octadecyl, eicosyl, and docosyl groups. Examples of the C8-C22 alkenyl group include the decenyl group.

[0090] Specific allyl compounds used in this embodiment include, for example, 5-octyl-1,3-diallyl isocyanurate, 5-dodecyl-1,3-diallyl isocyanurate, 5-tetradecyl-1,3-diallyl isocyanurate, 5-hexadecyl-1,3-diallyl isocyanurate, 5-octadecyl-1,3-diallyl isocyanurate, 5-eicosyl-1,3-diallyl isocyanurate, 5-docosyl-1,3-diallyl isocyanurate, and 5-decenyl-1,3-diallyl isocyanurate.

[0091] The method for producing the allyl compound in this embodiment is not particularly limited, but for example, the allyl compound can be obtained by reacting diallyl isocyanurate and alkyl halide in an aprotic polar solvent such as N,N'-dimethylformamide in the presence of a basic substance such as sodium hydroxide, potassium carbonate, or triethylamine at a temperature of about 60°C to 150°C.

[0092] (Inorganic fillers) The resin composition according to this embodiment may further contain an inorganic filler. Examples of inorganic fillers include those added to enhance the heat resistance and flame retardancy of the cured resin composition, and are not particularly limited. It is believed that by including an inorganic filler, it is possible to further enhance the heat resistance and flame retardancy, as well as suppress the increase in the coefficient of thermal expansion.

[0093] Examples of inorganic fillers that can be used in this embodiment include silica such as spherical silica, alumina, titanium oxide, metal oxides such as mica, metal hydroxides such as aluminum hydroxide and magnesium hydroxide, talc, aluminum borate, barium sulfate, and calcium carbonate. Among these, silica, mica, and talc are preferred, and spherical silica is more preferred. Furthermore, one type of inorganic filler may be used alone, or two or more types may be used in combination. In addition, the inorganic fillers described above may be used as is, or they may be surface-treated with an epoxysilane type, vinylsilane type, methacrylicsilane type, or aminosilane type silane coupling agent. This silane coupling agent can be added by integral blending rather than by pre-surface treatment of the filler.

[0094] (Styrene polymer) The resin composition of this embodiment may also contain styrene polymers in addition to the components described above. Including styrene polymers is thought to offer advantages such as improved handling properties (resin flowability) when the resin composition is made into a varnish, and further reduction of the dielectric constant of the resin.

[0095] The styrene-based polymer used in this embodiment is, for example, a polymer obtained by polymerizing monomers containing a styrene-based monomer, and may also be a styrene-based copolymer. Examples of the styrene-based copolymer include copolymers obtained by copolymerizing one or more styrene-based monomers with one or more other monomers copolymerizable with the styrene-based monomer. Examples of styrene-based monomers include styrene and styrene derivatives.

[0096] Specific styrene-based polymers can be broadly used from those already known and are not particularly limited, but examples include polymers having a structural unit (a structure derived from a styrene monomer) represented by the following formula (15) in their molecule.

[0097] [ka]

[0098] In formula (15), R 39 ~R 41 Each independently represents a hydrogen atom or an alkyl group, R 42 The group is 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. The alkenyl group is preferably an alkenyl group having 1 to 10 carbon atoms. Specifically, examples include a methyl group, an ethyl group, a propyl group, a hexyl group, and a decyl group.

[0099] The styrene-based polymer of this embodiment preferably contains at least one structural unit represented by formula (15), but may also contain a combination of two or more different types. Furthermore, it may contain a structure in which the structural unit represented by formula (15) is repeated.

[0100] Furthermore, in addition to the structural unit represented by formula (15) above, the styrene polymer of this embodiment may also have at least one of the structural units represented by the following formulas (16), (17), and (18) as other monomers copolymerizable with the styrene monomer.

[0101] [ka]

[0102] [ka]

[0103] [ka]

[0104] In equations (16), (17), and (18) above, R 43 ~R 60Each 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. The alkenyl group is preferably an alkenyl group having 1 to 10 carbon atoms. Specifically, examples include a methyl group, an ethyl group, a propyl group, a hexyl group, and a decyl group. The styrene polymer of this embodiment preferably contains at least one of the structural units represented by formulas (16), (17), and (18), and may contain a combination of two or more different types. It may also contain a structure in which the structural units represented by formulas (16), (17), and / or (18) are repeated.

[0105] Furthermore, more specifically, structural units represented by formula (15) above include, for example, the structural units represented by formulas (19) to (21) below. The structural unit represented by formula (15) above may be one of these alone, or it may be a combination of two or more different types. Moreover, it may also be a structure in which the structural units represented by formulas (19) to (21) below are repeated.

[0106] [ka]

[0107] More specifically, structural units represented by formula (16) above include, for example, the structural units represented by formulas (22) to (28) below. The structural unit represented by formula (16) above may be one of these types alone, or it may be a combination of two or more different types. Furthermore, it may also be a structure in which the structural units represented by formulas (22) to (28) below are repeated.

[0108] [ka]

[0109] [ka]

[0110] [ka]

[0111] [ka]

[0112] [ka]

[0113] [ka]

[0114] [ka]

[0115] Furthermore, more specifically, structural units represented by formula (17) above include, for example, the structural units represented by formulas (29) to (30) below. The structural unit represented by formula (17) above may be one of these alone, or it may be a combination of two or more different types. Moreover, it may also be a structure in which the structural units represented by formulas (29) to (30) below are repeated.

[0116] [ka]

[0117] [ka]

[0118] Furthermore, more specifically, structural units represented by formula (18) include, for example, the structural units represented by formulas (31) to (32) below. The structural unit represented by formula (18) above may be one of these alone, or it may be a combination of two or more different types. Moreover, it may also be a structure in which the structural units represented by formulas (31) to (32) below are repeated.

[0119] [ka]

[0120] [ka]

[0121] Preferred examples of styrene-based polymers include polymers or copolymers obtained by polymerizing or copolymerizing one or more styrene-based monomers such as styrene, vinyltoluene, α-methylstyrene, isopropenyltoluene, divinylbenzene, and allylstyrene. More specifically, examples include styrene-butadiene copolymers, styrene-isobutylene copolymers, and styrene-isobutylene-styrene copolymers. Hydrogenated styrene-based polymers are also acceptable, such as hydrogenated methylstyrene (ethylene / butylene)methylstyrene copolymers, hydrogenated methylstyrene (ethylene-ethylene / propylene)methylstyrene copolymers, hydrogenated styrene-isoprene copolymers, hydrogenated styrene-isoprenestyrene copolymers, hydrogenated styrene (ethylene / butylene)styrene copolymers, and hydrogenated styrene (ethylene-ethylene / propylene)styrene copolymers.

[0122] The styrene-based polymer may be one of the examples given above, or two or more may be used in combination.

[0123] In the styrene-based polymer, when it contains at least one of the structural units represented by formulas (19) to (21), its mole fraction is preferably about 10 to 40% of the total polymer, and more preferably about 15 to 35%. This has the further advantage of maintaining compatibility with the resin, thereby ensuring uniformity of properties within the resin composition.

[0124] The polymerization form of the styrene-based polymer is not particularly limited and may be a block copolymer, alternating copolymer, random copolymer, graft copolymer, etc. Furthermore, its form may be liquid, solid, elastomer, etc., and it may also be hydrogenated.

[0125] The number-average molecular weight of the styrene polymer in this embodiment is preferably around 50,000 to 200,000, and more preferably around 50,000 to 150,000. Having a number-average molecular weight within this range has the advantage of ensuring proper resin fluidity in the B-stage of the cured resin. Here, the number-average molecular weight can be measured using any general molecular weight measurement method, specifically, values ​​measured using gel permeation chromatography (GPC).

[0126] The styrene-based polymer used in this embodiment can also be a commercially available product, such as "SIBSTAR® 073T" from Kaneka Corporation, "Septon V9827" and "Septon 2002" from Kuraray Co., Ltd., and "ToughTec® H1041" from Asahi Kasei Corporation.

[0127] (Content of each component) In the resin composition of this embodiment, the content of the polyphenylene ether compound is preferably 10 to 90 parts by mass, more preferably 15 to 80 parts by mass, and even more preferably 20 to 70 parts by mass, based on 100 parts by mass of the total of the polyphenylene ether compound, the allyl compound, and (if the styrene polymer is included, the styrene polymer). That is, the content of the polyphenylene ether compound is preferably 10 to 90% by mass relative to the components other than the inorganic filler in the resin composition. If the content of the polyphenylene ether compound is within the above range, it is considered that a resin composition with low dielectric properties and high heat resistance can be obtained more reliably.

[0128] Furthermore, the content of the allyl compound is preferably 10 to 50 parts by mass, and more preferably 15 to 50 parts by mass, based on 100 parts by mass of the total of the polyphenylene ether compound, the allyl compound, and (if the styrene polymer is included, the styrene polymer) in the resin composition. It is believed that if the content of the allyl compound is within the above range, the resin composition will have superior toughness of the cured product.

[0129] Furthermore, if the resin composition of this embodiment contains the styrene polymer, the content of the styrene polymer is preferably 10 to 60 parts by mass, and more preferably 15 to 60 parts by mass, based on 100 parts by mass of the total of the polyphenylene ether compound, the allyl compound, and the styrene polymer in the resin composition. It is believed that if the content of the styrene polymer is within the above range, the resin flowability and varnish handling properties will be further improved.

[0130] Furthermore, if the resin composition of this embodiment contains an inorganic filler, the amount of the inorganic filler is preferably 50 to 300 parts by mass, more preferably 70 to 300 parts by mass, and even more preferably 100 to 300 parts by mass, based on 100 parts by mass of the total of the polyphenylene ether compound, the allyl compound, and (if the styrene polymer is included, the styrene polymer). It is believed that if the amount of the inorganic filler is within the above range, it is possible to suppress the increase in the coefficient of thermal expansion in the cured product and to suppress the increase in resin flowability.

[0131] <Other ingredients> The resin composition according to this embodiment may contain components other than those described above (other components) as necessary, as long as they do not impair the effects of the present invention. Other components contained in the resin composition according to this embodiment may further include additives such as reaction initiators, silane coupling agents, flame retardants, defoaming agents, antioxidants, heat stabilizers, antistatic agents, ultraviolet absorbers, dyes and pigments, dispersants and lubricants. In addition, the resin composition of this embodiment may contain other thermosetting resins such as epoxy resins, maleimide resins, aromatic hydrocarbon resins and aliphatic hydrocarbon resins, in addition to the polyphenylene ether compound, the allyl compound and the heavy styrene composite.

[0132] As described above, the resin composition according to this embodiment may contain a reaction initiator. Even if the resin composition contains the polyphenylene ether compound, the curing agent, and the polymer, the curing reaction can still proceed. 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.

[0133] The reaction initiator is not particularly limited as long as it can promote the curing reaction of the resin composition. Specifically, examples include metal oxides, azo compounds, peroxides, and the like.

[0134] Examples of metal oxides include metal carboxylate salts.

[0135] Examples of peroxides include α,α'-di(t-butylperoxy)diisopropylbenzene, 2,5-dimethyl-2,5-di(t-butylperoxy)-3-hexine, benzoyl peroxide, 3,3',5,5'-tetramethyl-1,4-diphenoquinone, chloranil, 2,4,6-tri-t-butylphenoxyl, t-butylperoxyisopropyl monocarbonate, and azobisisobutyronitrile.

[0136] 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).

[0137] Among the preferred reaction initiators, α,α'-di(t-butylperoxy)diisopropylbenzene is preferably used. α,α'-di(t-butylperoxy)diisopropylbenzene has low volatility, so it does not volatilize during drying or storage, resulting in good stability. Furthermore, because α,α'-di(t-butylperoxy)diisopropylbenzene has a relatively high reaction initiation temperature, it can suppress the acceleration of the curing reaction at points where curing is not required, such as during prepreg drying. This suppression of the curing reaction helps to prevent a decrease in the shelf life of the resin composition.

[0138] The reaction initiators described above may be used individually or in combination of two or more.

[0139] If the resin composition of this embodiment contains the reaction initiator, the amount thereof is not particularly limited, but for example, it is preferably 0.5 to 2.0 parts by mass, more preferably 0.8 to 1.5 parts by mass, and even more preferably 0.9 to 1.0 parts by mass, based on 100 parts by mass of the total of the polyphenylene ether compound, the allyl compound, and (if the styrene polymer is included, further including the styrene polymer).

[0140] (Prepregs, resin-coated films, metal-clad laminates, wiring boards, and resin-coated metal foils) Next, we will describe prepregs for wiring boards, metal-clad laminates, wiring boards, and resin-coated metal foils using the resin composition of this embodiment.

[0141] Figure 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, each reference numeral indicates: 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.

[0142] 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 containing the thermally expandable microcapsules, and a fibrous base material 3. An example of this prepreg 1 is one in which the fibrous base material 3 is present within the resin composition or its semi-cured product 2. That is, this prepreg 1 comprises the resin composition or its semi-cured product, and the fibrous base material 3 present within the resin composition or its semi-cured product 2.

[0143] In this embodiment, "semi-cured product" refers to a resin composition that has been partially cured to the extent that it can be further cured. In other words, a semi-cured product is a resin composition that has been partially cured (stage B). For example, when a resin composition is heated, its viscosity gradually decreases at first, then curing begins, and the viscosity gradually increases. In such a case, a semi-cured state would be the state between when the viscosity begins to increase and when it is not yet completely cured.

[0144] The prepreg obtained using the resin composition according to this embodiment may include a semi-cured product of the resin composition as described above, or it may include the uncured resin composition itself. That is, it may be a prepreg comprising a semi-cured product of the resin composition (the resin composition in stage B) and a fibrous substrate, or it may be a prepreg comprising the uncured resin composition (the resin composition in stage A) and a fibrous substrate. Specifically, for example, a resin composition may contain a fibrous substrate. The resin composition or its semi-cured product may be obtained by heat-drying the resin composition.

[0145] The resin composition according to this embodiment is often prepared in a varnish-like form and used as a resin varnish when manufacturing the prepreg, or resin-coated metal foil or metal-clad laminate described later. Such a resin varnish is prepared, for example, as follows.

[0146] First, each component that can be dissolved in an organic solvent, such as the resin component and reaction initiator, is added to the organic solvent and dissolved. Heating may be performed as needed. Then, an inorganic filler or the like, which is a component that does not dissolve in the organic solvent, is added and 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 modified polyphenylene ether compound, the allyl compound, and the styrene polymer, etc., and does not inhibit the curing reaction. Specifically, examples include toluene, methyl ethyl ketone, cyclohexanone, and propylene glycol monomethyl ether acetate. These may be used individually or in combination of two or more.

[0147] A method for producing the prepreg 1 of this embodiment using the varnish-like resin composition of this embodiment is, for example, to impregnate a fibrous substrate 3 with the resin varnish-like resin composition 2 and then dry it.

[0148] Specific examples of fibrous base materials used in the manufacture of prepregs include glass cloth, aramid cloth, polyester cloth, LCP (liquid crystal polymer) nonwoven fabric, glass nonwoven fabric, aramid nonwoven fabric, polyester nonwoven fabric, pulp paper, and linter paper. When glass cloth is used, a laminate with excellent mechanical strength can be obtained, and flattened glass cloth is particularly preferred. The glass cloth used in this embodiment is not particularly limited, but examples include low dielectric constant glass cloths such as E glass, S glass, NE glass, Q glass, and L glass. Specifically, the flattening process can be carried out, for example, by continuously pressing the glass cloth with a press roll at an appropriate pressure to flatten the yarn. The thickness of the fibrous base material can generally be 0.01 to 0.3 mm.

[0149] The resin varnish (resin composition 2) is impregnated into the fibrous substrate 3 by dipping, coating, etc. This impregnation can be repeated multiple times as needed. Furthermore, it is possible to repeat the impregnation using multiple resin varnishes with different compositions and concentrations to finally adjust to the desired composition (content ratio) and resin amount.

[0150] A fibrous substrate 3 impregnated with resin varnish (resin composition 2) is heated under desired heating conditions, for example, at 80°C or higher and 180°C or lower for 1 minute or more and 10 minutes or less. Heating causes the solvent to evaporate from the varnish, reducing or removing the solvent to obtain a prepreg 1 in a pre-cured state (Stage A) or a semi-cured state (Stage B).

[0151] Furthermore, as shown in Figure 4, the resin-coated metal foil 31 of this embodiment has a structure in which a resin layer 32 containing the above-mentioned resin composition or a semi-cured product of the resin composition and a metal foil 13 are laminated together. That is, the resin-coated metal foil of this embodiment may be a resin-coated metal foil comprising a resin layer containing the resin composition before curing (the resin composition in stage A) and a metal foil, or it may be a resin-coated metal foil comprising a resin layer containing a semi-cured product of the resin composition (the resin composition in stage B) and a metal foil.

[0152] One method for producing such resin-coated metal foil 31 is to apply a resin varnish-like resin composition, as described above, to the surface of a metal foil 13 such as copper foil, and then dry it. Examples of such application methods include bar coaters, comma coaters, die coaters, roll coaters, gravure coaters, and the like.

[0153] The metal foil 13 can be any metal foil used in metal-clad laminates, wiring boards, etc., for example, copper foil and aluminum foil.

[0154] Furthermore, as shown in Figure 5, the resin-coated film 41 of this embodiment has a structure in which a resin layer 42 containing the above-mentioned resin composition or a semi-cured product of the resin composition and a film support substrate 43 are laminated together. That is, the resin-coated film of this embodiment may be a resin-coated film comprising the resin composition before curing (the resin composition in stage A) and a film support substrate, or it may be a resin-coated film comprising a semi-cured product of the resin composition (the resin composition in stage B) and a film support substrate.

[0155] As a method for producing such a resin-coated film 41, for example, a resin varnish-like resin composition as described above can be applied to the surface of a film support substrate 43, and then the solvent can be evaporated from the varnish to reduce the amount of solvent, or the solvent can be removed, thereby obtaining a resin-coated film in a pre-cured state (Stage A) or a semi-cured state (Stage B).

[0156] Examples of the film support substrate include electrically insulating films such as polyimide film, PET (polyethylene terephthalate) film, polyester film, polyparabanic acid film, polyether ether ketone film, polyphenylene sulfide film, aramid film, polycarbonate film, and polyarylate film.

[0157] In addition, in the resin-coated film and resin-coated metal foil of this embodiment, similar to the prepreg described above, the resin composition or its semi-cured product may be obtained by drying or heat-drying the resin composition.

[0158] The thickness of the metal foil 13 and the film support substrate 43 can be set appropriately according to the desired purpose. For example, the metal foil 13 can be approximately 0.2 to 70 μm thick. If the thickness of the metal foil is, for example, 10 μm or less, a carrier-equipped copper foil with a release layer and carrier may be used to improve handling. The resin varnish is applied to the metal foil 13 and the film support substrate 43 by coating, and this can be repeated multiple times as needed. In this case, it is also possible to repeatedly coat using multiple resin varnishes with different compositions and concentrations to finally adjust to the desired composition (content ratio) and amount of resin.

[0159] The drying or heat drying conditions in the manufacturing method of the resin-coated metal foil 31 and resin film 41 are not particularly limited, but after applying the resin varnish-like resin composition to the metal foil 13 or film support substrate 43, the resin is heated under desired heating conditions, for example, at 80 to 170°C for about 1 to 10 minutes, to volatilize the solvent from the varnish and reduce or remove the solvent, thereby obtaining the resin-coated metal foil 31 or resin film 41 in a pre-cured state (A stage) or a semi-cured state (B stage).

[0160] The resin-coated metal foil 31 and the resin film 41 may be provided with a cover film or the like, if necessary. Providing a cover film can prevent the incorporation of foreign matter. The cover film is not particularly limited as long as it can be peeled off without damaging the form of the resin composition, but for example, polyolefin film, polyester film, TPX film, films formed by providing a release agent layer on these films, and paper obtained by laminating these films onto a paper substrate can be used.

[0161] As shown in Figure 2, the metal-clad laminate 11 of this embodiment is characterized by having an insulating layer 12 containing a cured product of the resin composition described above or a cured product of the prepreg described above, and a metal foil 13. The metal foil 13 used in the metal-clad laminate 11 can be the same as the metal foil 13 described above.

[0162] Furthermore, the metal-clad laminate 11 of this embodiment can also be made using the resin-coated metal foil 31 or resin film 41 described above.

[0163] As a method for producing a metal-clad laminate using the prepreg 1, resin-coated metal foil 31, or resin film 41 obtained as described above, one or more sheets of the prepreg 1, resin-coated metal foil 31, or resin film 41 are stacked, and then metal foil 13 such as copper foil is stacked on both the top and bottom surfaces or on one or both surfaces. This is then heated and pressurized to create a laminate that is metal-clad on both sides or on one side. The heating and pressurizing conditions can be appropriately set depending on the thickness of the laminate to be manufactured and the type of resin composition, but for example, the temperature can be set to 170-220°C, the pressure to 1.5-5.0 MPa, and the time to 60-150 minutes.

[0164] Alternatively, the metal-clad laminate 11 may be manufactured by forming a film-like resin composition on a metal foil 13 and then heating and pressurizing it, without using a prepreg 1 or the like.

[0165] As shown in Figure 3, the wiring board 21 of this embodiment has an insulating layer 12 containing a cured product of the resin composition or a cured product of the prepreg described above, and wiring 14.

[0166] The resin composition of this embodiment is suitably used as a material for the insulating layer of a wiring board. As a method for manufacturing the wiring board 21, for example, a wiring board 21 can be obtained by etching the metal foil 13 on the surface of the metal-clad laminate 13 obtained above to form circuits (wirings), thereby providing a conductor pattern (wirings 14) as a circuit on the surface of the laminate. In addition to the method described above, other methods for forming circuits include, for example, circuit formation by the semi-additive process (SAP) or the modified semi-additive process (MSAP).

[0167] The prepregs, resin-coated films, and resin-coated metal foils obtained using the resin composition of this embodiment are extremely useful for industrial applications because, in their cured form, they possess low dielectric properties and high Tg, while also exhibiting excellent toughness and handling properties. Furthermore, the metal-clad laminates and wiring boards obtained by curing them have the advantages of low dielectric properties, high Tg, and excellent handling properties.

[0168] 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]

[0169] First, we will describe each component used in preparing the resin composition in this embodiment.

[0170] (Polyphenylene ether compounds) • PPE1: Modified polyphenylene ether obtained by modifying the terminal hydroxyl groups of polyphenylene ether with methacrylic groups (SA9000 manufactured by SABIC Innovative Plastics, with an intrinsic viscosity (IV) of 0.085 dl / g in methylene chloride at 25°C, weight-average molecular weight Mw 1700, and 1.8 terminal functional groups).

[0171] The intrinsic viscosity was obtained by measuring a 0.18 g / 45 ml methylene chloride solution of modified polyphenylene ether (at a liquid temperature of 25°C) using a viscometer (Schott AVS500 Visco System).

[0172] • PPE2: Bifunctional vinyl benzyl-modified PPE (Mw: 1700) First, modified polyphenylene ether (modified PPE-1) was synthesized. The average number of phenolic hydroxyl groups at the molecular ends of one polyphenylene ether molecule is referred to as the number of terminal hydroxyl groups.

[0173] Modified polyphenylene ether 1 (modified PPE-1) was obtained by reacting polyphenylene ether with chloromethylstyrene. Specifically, first, 200 g of polyphenylene ether (SA90, manufactured by SABIC Innovative Plastics, with an intrinsic viscosity (IV) of 0.083 dl / g, 1.9 terminal hydroxyl groups, and a weight molecular weight of Mw1700), 30 g of a mixture of p-chloromethylstyrene and m-chloromethylstyrene in a mass ratio of 50:50 (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-necked flask equipped with a temperature controller, a stirrer, a cooling device, and a dropping funnel, and the mixture was stirred. The mixture was then stirred until the polyphenylene ether, chloromethylstyrene, and tetra-n-butylammonium bromide dissolved in the toluene. During this process, the mixture was gradually heated until the liquid temperature reached 75°C. Then, an aqueous solution of sodium hydroxide (20 g sodium hydroxide / 20 g water) was added dropwise to the solution over 20 minutes as an alkali metal hydroxide. After that, the mixture was stirred at 75°C for 4 hours. Next, the contents of the flask were neutralized with 10% by mass hydrochloric acid, and then a large amount of methanol was added. This caused a precipitate to form in the liquid in the flask, that is, the products contained in the reaction mixture in the flask were reprecipitated. This precipitate was then removed by filtration, washed three times with a methanol-water mixture in a mass ratio of 80:20, and then dried under reduced pressure at 80°C for 3 hours.

[0174] The obtained solid, 1 The sample was analyzed by 1H-NMR (400 MHz, CDCl3, TMS). NMR analysis revealed peaks originating from ethenylbenzyl at 5–7 ppm. This confirmed that the obtained solid is a polyphenylene ether with ethenylbenzylation at its molecular ends.

[0175] Furthermore, the molecular weight distribution of the modified polyphenylene ether was measured using GPC. From the obtained molecular weight distribution, the weight-average molecular weight (Mw) was calculated to be 1700.

[0176] Furthermore, the number of terminal functional groups in the modified polyphenylene ether was measured as follows.

[0177] First, the modified polyphenylene ether was accurately weighed. Let the weight be X (mg). Then, this weighed modified polyphenylene ether was dissolved in 25 mL of methylene chloride, and 100 μL of an ethanol solution of 10% by mass 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, Shimadzu Corporation). From the measurement results, the number of terminal hydroxyl groups of the modified polyphenylene ether was calculated using the following formula.

[0178] Residual OH amount (μmol / g) = [(25×Abs) / (ε×OPL×X)]×10 6 Here, ε represents the extinction coefficient, which is 4700 L / mol·cm. OPL is the cell path length, which is 1 cm.

[0179] Furthermore, the calculated residual OH amount (number of terminal hydroxyl groups) of the modified polyphenylene ether was almost zero, indicating that the hydroxyl groups of the polyphenylene ether before modification were almost completely modified. From this, it was found that the decrease from the number of terminal hydroxyl groups of the polyphenylene ether before modification corresponds to the number of terminal hydroxyl groups of the polyphenylene ether before modification. In other words, the number of terminal hydroxyl groups of the polyphenylene ether before modification corresponds to the number of terminal functional groups of the modified polyphenylene ether. That is, the number of terminal functional groups was 1.8. Let's call this "PPE2".

[0180] (Allyl compounds) • Production of allyl compound A In a 1 L three-necked round-bottom flask equipped with a stirrer and condenser, 104.5 g (0.5 mol) of diallyl isocyanurate, 0.5 mol of C8 alkyl halide, and 48.4 g (0.35 mol) of potassium carbonate were charged, along with 400 ml of N,N'-dimethylformamide as a solvent. The mixture was heated while stirring and maintained at 140°C for 4 hours. After removing the solvent under reduced pressure, 400 ml of benzene was added to the reaction product to extract the target product. After washing the extract with water, it was dried over anhydrous magnesium sulfate, and the benzene was further removed by distillation to obtain allyl compound A: long-chain alkyl-modified diallyl isocyanurate (C8). • Production of allyl compound B Allyl compound B: long-chain alkyl-modified diallyl isocyanurate (12 carbon atoms) was obtained by the same method as for allyl compound A, except that the alkyl halide was changed to an alkyl halide with 12 carbon atoms. • Production of allyl compound C Allyl compound C: long-chain alkyl-modified diallyl isocyanurate (14 carbon atoms) was obtained by the same method as for allyl compound A, except that the alkyl halide was changed to an alkyl halide with 14 carbon atoms. • Production of allyl compound D Allyl compound D: long-chain alkyl-modified diallyl isocyanurate (18 carbon atoms) was obtained by the same method as for allyl compound A, except that the alkyl halide was changed to an alkyl halide with 18 carbon atoms. • Production of allyl compound E Allyl compound E: long-chain alkylene-modified diallyl isocyanurate (10 carbon atoms) was obtained by the same method as for allyl compound A, except that the alkyl halide was replaced with a C10 alkylene halide.

[0181] (Other hardening agents) • TAIC: Triallyl isocyanurate (manufactured by Nippon Chemical Corporation) • MeDAIC: Methyldiallyl isocyanurate (manufactured by Shikoku Chemicals Co., Ltd.) • TMAIC: Trimetallyl isocyanurate (manufactured by Nippon Chemical Corporation) • DVB-810: Divinylbenzene (manufactured by Nippon Steel & Sumitomo Metal Chemical Co., Ltd.)

[0182] (Styrene polymer) • Septon V9827: Hydrogenated methylstyrene (ethylene / butylene) methylstyrene copolymer (manufactured by Kuraray Co., Ltd., weight-average molecular weight 92,000) • Septon 2002: Hydrogenated styrene (ethylene / propylene) styrene copolymer (manufactured by Kuraray Co., Ltd., weight-average molecular weight 54,000) • ToughTec H1041: Hydrogenated styrene (ethylene / butylene) styrene copolymer (manufactured by Asahi Kasei Corporation, 75,000) • SIBSTAR073T: Styrene-isobutylene-styrene triblock copolymer (manufactured by Kaneka Corporation, weight-average molecular weight 80,000)

[0183] (Reaction initiator) • Peroxide: "Perbutyl P", 1,3-bis(butylperoxyisopropyl)benzene (manufactured by Nippon Oil & Fats Co., Ltd.)

[0184] (Inorganic filler) • Silica particles: "SC2300-SVJ" vinylsilane-treated spherical silica (manufactured by Admatex Co., Ltd.)

[0185] <Examples 1-15, Comparative Examples 1-6> [Preparation method] (Resin varnish) First, the resin components (PPE, allyl compounds, styrene polymers, etc.) were added to toluene in the proportions (parts by mass) shown in Tables 1 and 2, so that the solid content concentration was 60% by mass, and then mixed. Peroxides, inorganic fillers, etc. were added to the mixture, and after stirring for 60 minutes, the mixture was dispersed using a bead mill to obtain a resin varnish.

[0186] (Resin-coated film and evaluation substrate) Resin-coated films were prepared using the resin varnishes of each example and comparative example prepared above. A PET film (SP-PETO1, manufactured by Mitsui Chemicals Tohcello Co., Ltd.) was used as the substrate. The resin varnish was applied to the substrate surface to a thickness of 130 μm or more after drying, and this was heated and dried at 120-160°C for approximately 2-5 minutes to obtain a resin-coated film. The substrate was then peeled off from the obtained resin-coated film, sandwiched between 35 μm thick copper foils and laminated, and heated and pressurized at 200°C and 4 MPa for 2 hours to obtain an evaluation substrate with an insulating layer thickness of 130 μm.

[0187] <Evaluation Test> (Handling: Cutter cut) A cutter knife blade was inserted into the evaluation substrate at a 20° angle, and a 10cm long cut was formed at a cutting speed of 2cm / sec. The area of ​​resin chipping around the formed cut was measured. ◎: Area of ​​resin chipping around the cut surface is 5mm 2 less than ○: Area of ​​resin chipping around the cut surface is 5mm 2 50mm or more 2 less than △: Area of ​​resin chipping around the cut surface is 50mm 2 100mm or more 2 less than ×: Area of ​​resin chipping around the cut surface is 100mm 2 That's all.

[0188] (modulus of elasticity) The elastic modulus of the evaluation substrate was measured using a viscoelastic spectrometer "DMS100" manufactured by Seiko Instruments Inc. Specifically, dynamic viscoelasticity measurement (DMA) was performed with a tensile module at a frequency of 10 Hz, and the storage modulus E'(GPa) at room temperature (25°C) was measured when the temperature was raised from room temperature to 280°C under a heating rate of 5°C / min.

[0189] In this test, a low modulus of elasticity indicates high toughness, and a modulus of elasticity of 4 GPa or less is considered a passing grade.

[0190] (Glass transition temperature (Tg)) The Tg of the aforementioned evaluation substrate was measured using a viscoelastic spectrometer "DMS100" manufactured by Seiko Instruments Inc. Dynamic viscoelasticity measurement (DMA) was performed using a tensile module at a frequency of 10 Hz. Tg was defined as the temperature at which tanδ was maximized when the temperature was increased from room temperature to 300°C at a heating rate of 5°C / min. In this example, a Tg of 160°C or higher was considered acceptable.

[0191] (Dielectric properties: Dielectric loss tangent (Df)) The dielectric loss tangent (Df) of the evaluation substrate was measured using the cavity resonator perturbation method. Specifically, a network analyzer (N5230A manufactured by Agilent Technologies, Inc.) was used to measure the dielectric loss tangent (Df) of the test specimen at 10 GHz. In this example, a Df of 0.0016 or less was considered acceptable.

[0192] (Resin flowability) Resin flowability was evaluated using the resin-coated film described above. The resin varnishes of Examples 1 to 15 were measured in accordance with IPC-TM-650. The molding conditions were 171°C and a pressure of 14 kgf / cm². 2 The film was then pressed with a hot plate for 15 minutes. Two resin films, prepared as described above, were used for the measurement. The resin flowability value indicates the quality of circuit filling. If the resin flowability value is too low, the resin composition derived from the resin film does not sufficiently penetrate between the circuits, and voids are formed. In this example, a resin flowability of 10% or more is considered acceptable.

[0193] The results are shown in Tables 1 and 2.

[0194] [Table 1]

[0195] [Table 2]

[0196] (Consideration) As is clear from the results shown in Table 1, it was confirmed that the resin composition of the present invention yields a cured product with low dielectric properties and high Tg, while also exhibiting excellent handling properties and toughness. Furthermore, the resin composition of the example according to the present invention also exhibits excellent resin flowability, which is considered advantageous for circuit filling when creating multilayer wiring boards and the like.

[0197] In particular, in equation (3), R A It was also confirmed that handling performance is improved when an allyl compound with an alkyl or alkenyl group having 8 to 18 carbon atoms is used, or when a styrene polymer is used in combination.

[0198] In contrast, as is clear from Table 2, Comparative Examples 1 to 4, which did not use the allyl compound according to the present invention, showed a high elastic modulus and poor handling properties. Furthermore, in Comparative Example 5, in which the amount of allyl compound was increased without containing the polyphenylene ether compound, the cured product became brittle, making it impossible to measure the elastic modulus, and resulting in poor handling properties. In addition, Comparative Example 6, in which a styrene-based polymer was added instead of the polyphenylene ether compound, showed good handling properties, but a sufficient Tg could not be obtained.

[0199] This application is based on Japanese Patent Application No. 2020-146564, filed on September 1, 2020, and its contents are included in this application.

[0200] In order to express the present invention, the invention has been adequately and sufficiently described above through embodiments with reference to specific examples and drawings, etc. However, those skilled in the art should recognize that it is easy to modify and / or improve the embodiments described above. Therefore, unless the modifications or improvements implemented by those skilled in the art fall outside the scope of the claims described in the claims, such modifications or improvements shall be interpreted as being included within the scope of the claims. [Industrial applicability]

[0201] The present invention has broad industrial applicability in the field of technology relating to electronic materials and various devices using them.

Claims

1. A polyphenylene ether compound having at least one of the groups represented by the following formulas (1) and (2), A resin composition comprising an allyl compound represented by the following formula (3), A resin composition in which the cured product has a dielectric loss tangent of 0.0016 or less at 10 GHz. 【Chemistry 1】 (In formula (1), p represents an integer from 0 to 10. Z represents an arylene group. R １ ~R ３ (Each of these independently represents a hydrogen atom or an alkyl group.) 【Chemistry 2】 (In formula (2), R ４ (This represents a hydrogen atom or an alkyl group.) 【Transformation 3】 (In formula (3), R Ａ (This represents an alkyl or alkenyl group having 8 to 22 carbon atoms.)

2. The resin composition according to claim 1, further containing an inorganic filler.

3. The resin composition according to claim 1 or 2, wherein the allyl compound is contained in 10 to 50 parts by mass with respect to a total of 100 parts by mass of the polyphenylene ether compound and the allyl compound.

4. Furthermore, the resin composition according to any one of claims 1 to 3, further comprising a styrene polymer having a structural unit represented by the following formula (15). 【Chemistry 4】 (In formula (15), R ３９ ~R ４１ Each independently represents a hydrogen atom or an alkyl group, R ４２ (This indicates a group selected from the group consisting of a hydrogen atom, an alkyl group, an alkenyl group, and an isopropenyl group.)

5. The resin composition according to claim 4, wherein the allyl compound is contained in 10 to 50 parts by mass with respect to a total of 100 parts by mass of the polyphenylene ether compound, the allyl compound, and the styrene polymer.

6. The resin composition according to claim 4 or 5, wherein the weight-average molecular weight of the styrene polymer is 10,000 to 300,000.

7. The resin composition according to any one of claims 4 to 6, wherein the styrene polymer is at least one selected from the group consisting of hydrogenated methylstyrene (ethylene / butylene) methylstyrene copolymer, hydrogenated methylstyrene (ethylene-ethylene / propylene) methylstyrene copolymer, hydrogenated styrene isoprene copolymer, hydrogenated styrene isoprene styrene copolymer, hydrogenated styrene (ethylene / butylene) styrene copolymer, hydrogenated styrene (ethylene / propylene) styrene copolymer, hydrogenated styrene (ethylene-ethylene / propylene) styrene copolymer, styrene-isobutylene copolymer, and styrene-isobutylene-styrene copolymer.

8. The resin composition according to any one of claims 4 to 7, wherein the styrene polymer is contained in 10 to 60 parts by mass with respect to a total of 100 parts by mass of the polyphenylene ether compound, the allyl compound, and the styrene polymer.

9. The resin composition according to any one of claims 1 to 8, further comprising a reaction initiator.

10. A prepreg comprising a resin composition according to any one of claims 1 to 9 or a semi-cured product of the resin composition, and a fibrous substrate.

11. A resin-coated film having a resin layer containing the resin composition described in any one of claims 1 to 9 or a semi-cured product of the resin composition, and a support film.

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

13. A metal-clad laminate having an insulating layer containing a cured resin composition according to any one of claims 1 to 9 or a cured prepreg according to claim 10, and a metal foil.

14. A wiring substrate having an insulating layer containing a cured resin composition according to any one of claims 1 to 9 or a cured prepreg according to claim 10, and wiring.

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