WO2024057803A1

WO2024057803A1 - Resin composition, prepreg, film with resin, metal foil with resin, metal-clad laminate, and wiring board

Info

Publication number: WO2024057803A1
Application number: PCT/JP2023/029463
Authority: WO
Inventors: 幹男佐藤; 伸一勝田
Original assignee: パナソニックＩｐマネジメント株式会社
Priority date: 2022-09-16
Filing date: 2023-08-14
Publication date: 2024-03-21

Abstract

One aspect of the present invention relates to a resin composition comprising a radically polymerizable compound (A) that has a carbon-carbon unsaturated double bond in each molecule, a phosphate ester compound (B) that has an alicyclic hydrocarbon structure in each molecule, and an inorganic filler (C), wherein a cured product of said resin composition has a thermal conductivity of not less than 1.0W/m･K.

Description

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

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

As the amount of information processed in various electronic devices increases, mounting technologies such as higher integration of mounted semiconductor devices, higher wiring density, and multilayering are progressing. Moreover, as a wiring board used in various electronic devices, it is desirable to use a wiring board compatible with high frequencies, such as a millimeter wave radar board for in-vehicle applications. Wiring boards used in various electronic devices are required to reduce loss during signal transmission in order to increase signal transmission speed, and this is especially required for wiring boards compatible with high frequencies. Therefore, substrate materials for forming the substrates of wiring boards used in various electronic devices are required to have excellent low dielectric properties such as low relative permittivity and low dielectric loss tangent.

Additionally, wiring boards are required to have excellent flame retardancy. In this regard, resin compositions used as substrate materials often contain halogen-based flame retardants such as brominated flame retardants and halogen-containing compounds such as halogen-containing epoxy resins. A resin composition containing such a halogen-containing compound will contain a halogen in its cured product. When this cured product is burned, there is a risk of generating harmful substances such as hydrogen halides, and it has been pointed out that there is a concern that it will have an adverse effect on the human body and the natural environment. Against this background, substrate materials and the like are required to be halogen-free, that is, to be halogen-free.

Such a substrate material, for example, includes a thermosetting resin and a curing agent, and is compatible with a mixture of the thermosetting resin and curing agent as a halogen-free flame retardant, as disclosed in Patent Document 1. PPE-containing resin compositions are described that include compatible phosphorus compounds and incompatible phosphorus compounds that are incompatible with the mixture. It has been reported that by curing such a resin composition, a cured product having excellent low dielectric properties, flame retardance, etc. can be obtained (Patent Document 1).

On the other hand, in recent years, demands for various properties in insulating layers of wiring boards used in various electronic devices have further increased. For example, it is also desired that wiring boards used in various electronic devices be less susceptible to changes in the external environment. Specifically, in order to obtain a wiring board that has excellent reliability over a wide temperature range, there is a need for a technology that increases the thermal conductivity of a substrate material that constitutes the insulating layer of the wiring board. Further, it is also desired that the wiring board has excellent withstand voltage characteristics such that the withstand voltage does not deteriorate even in an environment with relatively high temperature and humidity. Therefore, the substrate material for constituting the insulating layer of the wiring board is also required to be a material that can yield a cured product that maintains excellent withstand voltage characteristics even after heat treatment and moisture absorption treatment.

However, research by the present inventors revealed that some compatible phosphorus compounds used as halogen-free phosphorus-based flame retardants generate phosphoric acid upon thermal decomposition, resulting in poor resistance after heat treatment and moisture absorption treatment. It has been found that the voltage deteriorates.

Furthermore, wiring boards used in various electronic devices are also required to have excellent adhesion between the metal foil (wiring) and the insulating layer. Metal-clad laminates and resin-coated metal foils used in manufacturing wiring boards and the like include not only an insulating layer but also a metal foil on the insulating layer. Further, the wiring board is also provided with not only an insulating layer but also wiring on the insulating layer. Examples of the wiring include wiring derived from metal foil provided in the metal-clad laminate or the like.

It is desired that the wiring board does not peel off from the insulating layer even if the wiring provided on the wiring board is a finer wiring. In order to meet this requirement, it is preferable that the wiring and the insulating layer have high adhesion in the wiring board. Therefore, metal-clad laminates are required to have high adhesion between the metal foil and the insulating layer, and the substrate material for forming the insulating layer of the wiring board must be a hardened material that has excellent adhesion to the metal foil. It is required that things be obtained.

The present invention has been made in view of the above circumstances, and has low dielectric properties (relative permittivity), excellent flame retardancy and adhesion to metal foil, high thermal conductivity, and It is possible to provide a resin composition from which a cured product is obtained in which deterioration of withstand voltage is suppressed.

International Publication No. 2018/074278

The resin composition according to one aspect of the present invention comprises a radically polymerizable compound (A) having a carbon-carbon unsaturated double bond in the molecule, and a phosphoric acid ester compound (A) having an alicyclic hydrocarbon structure in the molecule. B) and an inorganic filler (C), and the cured product thereof has a thermal conductivity of 1.0 W/m·K or more.

FIG. 1 is a schematic cross-sectional view showing an example of a prepreg according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional view showing an example of a metal-clad laminate according to an embodiment of the present invention. FIG. 3 is a schematic cross-sectional view showing an example of a wiring board according to an embodiment of the present invention. FIG. 4 is a schematic cross-sectional view showing an example of a resin-coated metal foil according to an embodiment of the present invention. FIG. 5 is a schematic cross-sectional view showing an example of a resin-coated film according to an embodiment of the present invention.

Hereinafter, embodiments according to the present invention will be described, but the present invention is not limited thereto.

[Resin composition]
The resin composition according to one embodiment of the present invention comprises a radically polymerizable compound (A) having a carbon-carbon unsaturated double bond in the molecule, and a phosphoric acid ester compound having an alicyclic hydrocarbon structure in the molecule. (B) and an inorganic filler (C), and the cured product has a thermal conductivity of 1.0 W/m·K or more. When cured, a resin composition with such a structure has low dielectric properties (relative permittivity), excellent adhesion to metal foil and flame retardancy, high thermal conductivity, and high resistance to heat and moisture absorption after heat treatment and moisture absorption treatment. A cured product with suppressed deterioration of withstand voltage can be obtained.

When the thermal conductivity of the cured product of the resin composition is 1.0 W/m·K or more, the heat dissipation properties of a substrate such as a wiring board using the cured product of the resin composition can be improved. The thermal conductivity is preferably 1.1 W/m·K or more, more preferably 1.2 W/m·K or more. Note that the upper limit of the thermal conductivity is not particularly limited, and is preferably a high value, but preferably 2.0 W/m·K or less. By setting the thermal conductivity to 2.0 W/m·K or less, a cured product with excellent adhesion to metal foil can be obtained more reliably.

Further, it is preferable that the cured product of the resin composition has a relative dielectric constant of 3.2 to 3.8 at a frequency of 10 GHz. The relative dielectric constant is more preferably 3.3 to 3.5.

(Radical polymerizable compound (A))
The radically polymerizable compound (A) is not particularly limited as long as it is a radically polymerizable compound having a carbon-carbon unsaturated double bond in its molecule. The radically polymerizable compound (A) preferably includes, for example, a polyphenylene ether compound (A1) having a carbon-carbon unsaturated double bond in the molecule. Thereby, low dielectric properties can be ensured in the cured product of the resin composition. It is more preferable to include the polyphenylene ether compound (A1) and the radically polymerizable compound (other radically polymerizable compound) (A2) other than the polyphenylene ether compound (A1). Examples of the other radically polymerizable compound (A2) include a curing agent for the polyphenylene ether compound (A1).

The polyphenylene ether compound (A1) is not particularly limited as long as it is a polyphenylene ether compound having a carbon-carbon unsaturated double bond in the molecule. Examples of the polyphenylene ether compound (A1) include polyphenylene ether compounds having a carbon-carbon unsaturated double bond at the end. More specifically, the polyphenylene ether compound (A1) is a substituted polyphenylene ether compound having a carbon-carbon unsaturated double bond, such as a modified polyphenylene ether compound terminal-modified with a substituent having a carbon-carbon unsaturated double bond. Examples include polyphenylene ether compounds having a group at the end of the molecule.

Examples of the substituent having a carbon-carbon unsaturated double bond include a group represented by the following formula (3) and a group represented by the following formula (4). That is, the polyphenylene ether compound (A1) is, for example, a polyphenylene ether compound having in its molecule at least one selected from a group represented by the following formula (3) and a group represented by the following formula (4). etc. The polyphenylene ether compound (A1) is preferably a polyphenylene ether compound having a group represented by the following formula (3) in the molecule. If so, low dielectric properties can be more reliably obtained in the cured product of the resin composition.

In formula (3), p represents 0 to 10. Ar ₃ represents an arylene group. R ₁₁ to R ₁₃ are each independent. That is, R ₁₁ to R ₁₃ may be the same group or different groups. R ₁₁ to R ₁₃ represent a hydrogen atom or an alkyl group. In addition, in the above formula (3), when p is 0, it indicates that Ar ₃ is directly bonded to the polyphenylene ether.

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

The alkyl group is not particularly limited, and for example, an alkyl group having 1 to 18 carbon atoms is preferable, and an alkyl group having 1 to 10 carbon atoms is more preferable. Specifically, examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a hexyl group, and a decyl group.

In formula (4), R ₁₄ represents a hydrogen atom or an alkyl group. The alkyl group is not particularly limited, and, for example, an alkyl group having 1 to 18 carbon atoms is preferable, and an alkyl group having 1 to 10 carbon atoms is more preferable. Specifically, examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a hexyl group, and a decyl group.

Examples of the group represented by the formula (3) include a vinylbenzyl group (ethenylbenzyl group) represented by the following formula (5). Furthermore, examples of the group represented by the formula (4) include an acryloyl group and a methacryloyl group.

More specifically, the substituent includes vinylbenzyl groups (ethenylbenzyl groups) such as o-ethenylbenzyl group, m-ethenylbenzyl group, and p-ethenylbenzyl group, vinylphenyl group, and acryloyl group. group, and methacryloyl group. The polyphenylene ether compound (A1) may have one type of substituent, or may have two or more types of substituents. The polyphenylene ether compound (A1) may have, for example, any one of an o-ethenylbenzyl group, a m-ethenylbenzyl group, and a p-ethenylbenzyl group, or two types thereof. Or it may have three types.

The polyphenylene ether compound (A1) has a polyphenylene ether chain in the molecule, and preferably has a repeating unit represented by the following formula (6) in the molecule.

In formula (6), t represents 1 to 50. Furthermore, R ₁₅ to R ₁₈ are each independent. That is, R ₁₅ to R ₁₈ may be the same group or different groups. Further, R ₁₅ to R ₁₈ 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.

Specific examples of the functional groups listed in R ₁₅ to R ₁₈ include the following.

The alkyl group is not particularly limited, but for example, an alkyl group having 1 to 18 carbon atoms is preferable, and an alkyl group having 1 to 10 carbon atoms is more preferable. Specifically, examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a hexyl group, and a decyl group.

The alkenyl group is not particularly limited, but for example, an alkenyl group having 2 to 18 carbon atoms is preferable, and an alkenyl group having 2 to 10 carbon atoms is more preferable. Specifically, examples of the alkenyl group include a vinyl group, an allyl group, and a 3-butenyl group.

The alkynyl group is not particularly limited, but for example, an alkynyl group having 2 to 18 carbon atoms is preferable, and an alkynyl group having 2 to 10 carbon atoms is more preferable. Specifically, examples of the alkynyl group include an ethynyl group and a prop-2-yn-1-yl group (propargyl group).

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 preferable, and an alkylcarbonyl group having 2 to 10 carbon atoms is more preferable. Specifically, examples of the alkylcarbonyl group 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.

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 preferable, and an alkenylcarbonyl group having 3 to 10 carbon atoms is more preferable. Specifically, examples of the alkenylcarbonyl group include an acryloyl group, a methacryloyl group, and a crotonoyl group.

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 preferable, and an alkynylcarbonyl group having 3 to 10 carbon atoms is more preferable. Specifically, the alkynylcarbonyl group includes, for example, a propioloyl group.

The weight average molecular weight (Mw) and number average molecular weight (Mn) of the polyphenylene ether compound (A1) are not particularly limited, but specifically, it is preferably 500 to 5000, more preferably 800 to 4000. It is preferably 1,000 to 3,000. Note that the weight average molecular weight and number average molecular weight here may be those measured by a general molecular weight measurement method, and specifically, the values measured using gel permeation chromatography (GPC) are listed. It will be done. In addition, when the polyphenylene ether compound (A1) has a repeating unit represented by the above formula (6) in the molecule, t is such that the weight average molecular weight and number average molecular weight of the polyphenylene ether compound are within such ranges. It is preferable that the value is within the range. Specifically, t in the above formula (6) is preferably 1 to 50.

When the weight average molecular weight and number average molecular weight of the polyphenylene ether compound (A1) are within the above ranges, the polyphenylene ether has excellent low dielectric properties, and the cured product not only has excellent heat resistance but also has good moldability. will also be excellent. This is thought to be due to the following. When the weight average molecular weight and number average molecular weight of ordinary polyphenylene ether are within the above ranges, the heat resistance tends to decrease because the molecular weight is relatively low. In this regard, since the polyphenylene ether compound (A1) has one or more unsaturated double bonds at the terminal, it is thought that as the curing reaction progresses, a cured product with sufficiently high heat resistance can be obtained. . Further, when the weight average molecular weight and number average molecular weight of the polyphenylene ether compound (A1) are within the above ranges, it is considered to have a relatively low molecular weight and therefore has excellent moldability. Therefore, it is thought that such a polyphenylene ether compound not only provides a cured product with excellent heat resistance but also excellent moldability.

In the polyphenylene ether compound (A1), the average number of the substituents (number of terminal functional groups) at the molecular ends per molecule of the polyphenylene ether compound is not particularly limited, but specifically, 1 to 5. The number is preferably 1 to 3, 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. Furthermore, if the number of terminal functional groups is too large, the reactivity becomes too high, which may cause problems such as a decrease in the storage stability of the resin composition or a decrease in the fluidity of the resin composition. In other words, when such a polyphenylene ether compound is used, molding defects such as voids occur during multilayer molding due to insufficient fluidity, resulting in poor moldability that makes it difficult to obtain a highly reliable printed wiring board. Problems may occur.

Note that the number of terminal functional groups of the polyphenylene ether compound includes a numerical value representing the average value of the substituents per molecule of all polyphenylene ether compounds present in 1 mole of the polyphenylene ether compound. The number of terminal functional groups can be determined, for example, by measuring the number of hydroxyl groups remaining in the obtained polyphenylene ether compound and calculating the decrease from the number of hydroxyl groups in the polyphenylene ether before having the substituent (before modification). , can be measured. The number of terminal functional groups is the decrease from the number of hydroxyl groups in the polyphenylene ether before modification. The method for measuring the number of hydroxyl groups remaining in a polyphenylene ether compound is to add a quaternary ammonium salt (tetraethylammonium hydroxide) that associates with hydroxyl groups to a solution of the polyphenylene ether compound, and measure the UV absorbance of the mixed solution. It can be found by

The intrinsic viscosity of the polyphenylene ether compound (A1) is not particularly limited, but specifically, it may be from 0.03 to 0.12 dl/g, but preferably from 0.04 to 0.11 dl/g. It is preferably 0.06 to 0.095 dl/g, and more preferably 0.06 to 0.095 dl/g. If the intrinsic viscosity is too low, the molecular weight tends to be low, making it difficult to obtain low dielectric properties such as a low dielectric constant and a low dielectric loss tangent. Moreover, 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 of the cured product can be achieved.

Note that the intrinsic viscosity here is the intrinsic viscosity measured in methylene chloride at 25°C, and more specifically, for example, a 0.18 g/45 ml methylene chloride solution (liquid temperature 25°C) is measured using a viscometer. These are the values measured in . Examples of this viscometer include AVS500 Visco System manufactured by Schott.

Examples of the polyphenylene ether compound (A1) include a polyphenylene ether compound represented by the following formula (7), a polyphenylene ether compound represented by the following formula (8), and the like. Further, as the polyphenylene ether compound (A1), these polyphenylene ether compounds may be used alone, or these two types of polyphenylene ether compounds may be used in combination.

In formulas (7) and (8), R ₁₉ to R ₂₆ and R ₂₇ to R ₃₄ are each independent. That is, R ₁₉ to R ₂₆ and R ₂₇ to R ₃₄ may be the same group or different groups. Furthermore, R ₁₉ to R ₂₆ and R ₂₇ to R ₃₄ 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. X ₁ and X ₂ are each independent. That is, X ₁ and X ₂ may be the same group or different groups. X ₁ and X ₂ represent substituents having a carbon-carbon unsaturated double bond. A and B represent repeating units represented by the following formula (9) and the following formula (10), respectively. Further, in formula (8), Y represents a linear, branched, or cyclic hydrocarbon having 20 or less carbon atoms.

In formulas (9) and (10), m and n each represent 0 to 20. R ₃₅ to R ₃₈ and R ₃₉ to R ₄₂ are each independent. That is, R ₃₅ to R ₃₈ and R ₃₉ to R ₄₂ may be the same group or different groups. Further, R ₃₅ to R ₃₈ and R ₃₉ to R ₄₂ 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.

The polyphenylene ether compound represented by the formula (7) and the polyphenylene ether compound represented by the formula (8) are not particularly limited as long as they satisfy the above configuration. Specifically, in the formula (7) and the formula (8), R ₁₉ to R ₂₆ and R ₂₇ to R ₃₄ are each independent, as described above. That is, R ₁₉ to R ₂₆ and R ₂₇ to R ₃₄ may be the same group or different groups. Furthermore, R ₁₉ to R ₂₆ and R ₂₇ to R ₃₄ 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.

In formulas (9) and (10), m and n each preferably represent 0 to 20, as described above. Further, m and n preferably represent numerical values such that the total value of m and n is 1 to 30. Therefore, it is more preferable that m represents 0 to 20, n represents 0 to 20, and the sum of m and n represents 1 to 30. Further, R ₃₅ to R ₃₈ and R ₃₉ to R ₄₂ are each independent. That is, R ₃₅ to R ₃₈ and R ₃₉ to R ₄₂ may be the same group or different groups. Further, R ₃₅ to R ₃₈ and R ₃₉ to R ₄₂ 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.

R ₁₉ to R ₄₂ are the same as R ₁₅ to R ₁₈ in the above formula (6).

In the formula (8), Y is a linear, branched, or cyclic hydrocarbon having 20 or less carbon atoms, as described above. Examples of Y include a group represented by the following formula (11).

In the formula (11), R ₄₃ and R ₄₄ each independently represent a hydrogen atom or an alkyl group. Examples of the alkyl group include a methyl group. Examples of the group represented by formula (11) include a methylene group, a methylmethylene group, and a dimethylmethylene group, and among these, a dimethylmethylene group is preferred.

In the formula (7) and the formula (8), X ₁ and X ₂ are each independently a substituent having a carbon-carbon double bond. In addition, in the polyphenylene ether compound represented by the formula (7) and the polyphenylene ether compound represented by the formula (8), X ₁ and X ₂ may be the same group or different groups. You can.

More specific examples of the polyphenylene ether compound represented by the formula (7) include, for example, the polyphenylene ether compound represented by the following formula (12).

More specific examples of the polyphenylene ether compound represented by the formula (8) include, for example, a polyphenylene ether compound represented by the following formula (13), a polyphenylene ether compound represented by the following formula (14), etc. can be mentioned.

In the above formulas (12) to (14), m and n are the same as m and n in the above formula (9) and the above formula (10). Furthermore, in the above formula (12) and the above formula (13), R ₁₁ to R ₁₃ , p, and Ar ₃ are the same as R ₁₁ to R ₁₃ , p, and Ar ₃ in the above formula (3). Further, in the above formula (13) and the above formula (14), Y is the same as Y in the above formula (8). Further, in the above formula (14), R ₁₄ is the same as R ₁₄ in the above formula (4).

The method for synthesizing the polyphenylene ether compound (A1) used in this embodiment is not particularly limited as long as it can synthesize a polyphenylene ether compound having a carbon-carbon unsaturated double bond in the molecule. Specifically, this method includes a method in which polyphenylene ether is reacted with a compound in which a substituent having a carbon-carbon unsaturated double bond and a halogen atom are bonded.

Examples of compounds in which a substituent having a carbon-carbon unsaturated double bond and a halogen atom are bonded include a compound in which a substituent represented by the formulas (3) to (5) above and a halogen atom are bonded. Examples include compounds. Specific examples of the halogen atom include a chlorine atom, a bromine atom, an iodine atom, and a fluorine atom, and among these, a chlorine atom is preferred. More specifically, the compounds in which a substituent having a carbon-carbon unsaturated double bond and a halogen atom are bonded include o-chloromethylstyrene, p-chloromethylstyrene, m-chloromethylstyrene, etc. can be mentioned. The compound in which a substituent having a carbon-carbon unsaturated double bond and a halogen atom are bonded may be used alone or in combination of two or more. For example, o-chloromethylstyrene, p-chloromethylstyrene, and m-chloromethylstyrene may be used alone, or two or three types may be used in combination.

The raw material polyphenylene ether is not particularly limited as long as it can ultimately synthesize a predetermined polyphenylene ether compound. Specifically, polyphenylene ethers such as poly(2,6-dimethyl-1,4-phenylene oxide) and polyphenylene ethers composed of 2,6-dimethylphenol and at least one of bifunctional phenols and trifunctional phenols are used. Examples include those having the main component. Moreover, a bifunctional phenol is a phenol compound having two phenolic hydroxyl groups in the molecule, and examples thereof include tetramethylbisphenol A and the like. Moreover, trifunctional phenol is a phenol compound having three phenolic hydroxyl groups in the molecule.

Examples of the method for synthesizing the polyphenylene ether compound (A1) include the method described above. Specifically, polyphenylene ether as 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 the substituent having the carbon-carbon unsaturated double bond and the halogen atom are bonded react, and the polyphenylene ether compound used in this embodiment is obtained.

The reaction is preferably carried out in the presence of an alkali metal hydroxide. It is thought that this reaction proceeds suitably by doing so. This is considered to be because the alkali metal hydroxide functions as a dehydrohalogenation agent, specifically, as a dehydrochlorination agent. That is, the alkali metal hydroxide eliminates hydrogen halide from the phenol group of polyphenylene ether, the compound in which the substituent having the carbon-carbon unsaturated double bond and the halogen atom are bonded, and so on. By doing so, it is thought that the substituent having the carbon-carbon unsaturated double bond bonds to the oxygen atom of the phenol group instead of the hydrogen atom of the phenol group of polyphenylene ether.

The alkali metal hydroxide is not particularly limited as long as it can function as a dehalogenating agent, and examples thereof include sodium hydroxide. Further, the alkali metal hydroxide is usually used in the form of an aqueous solution, specifically, as an aqueous sodium hydroxide solution.

Reaction conditions such as reaction time and reaction temperature vary depending on the compound in which a substituent having a carbon-carbon unsaturated double bond and a halogen atom are bonded, and the reaction conditions such as reaction time and reaction temperature are determined under conditions that allow the above-mentioned reaction to proceed suitably. If so, there are no particular limitations. Specifically, the reaction temperature is preferably room temperature to 100°C, more preferably 30 to 100°C. Further, the reaction time is preferably 0.5 to 20 hours, more preferably 0.5 to 10 hours.

The solvent used during the reaction can dissolve polyphenylene ether and the compound in which a substituent having the carbon-carbon unsaturated double bond and a halogen atom are bonded, and the solvent can dissolve the polyphenylene ether and the compound having the carbon-carbon unsaturated double bond. It is not particularly limited as long as it does not inhibit the reaction between a substituent having a double bond and a compound to which a halogen atom is bonded. Specifically, toluene etc. are mentioned.

The above reaction is preferably carried out in the presence of not only the alkali metal hydroxide but also a phase transfer catalyst. That is, the above reaction is preferably carried out in the presence of an alkali metal hydroxide and a phase transfer catalyst. It is thought that by doing so, the above reaction proceeds more suitably. This is thought to be due to the following. Phase transfer catalysts have the ability to take up alkali metal hydroxides, are soluble in both polar solvent phases such as water, and non-polar solvent phases such as organic solvents, and transfer between these phases. This is thought to be due to the fact that it is a catalyst that can transfer . Specifically, when an aqueous sodium hydroxide solution is used as the alkali metal hydroxide and an organic solvent such as toluene that is incompatible with water is used as the solvent, the aqueous sodium hydroxide solution is subjected to the reaction. Even if it is added dropwise to the solvent, the solvent and the aqueous sodium hydroxide solution will separate, and it is thought that the sodium hydroxide will be difficult to transfer to the solvent. In this case, it is thought that the aqueous sodium hydroxide solution added as the alkali metal hydroxide becomes less likely to contribute to the promotion of the reaction. On the other hand, 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 transferred to the solvent, and the aqueous sodium hydroxide solution is reacted. This is thought to make it easier to contribute to promotion. Therefore, it is considered that the above reaction proceeds more suitably when the reaction is carried out in the presence of an alkali metal hydroxide and a phase transfer catalyst.

The phase transfer catalyst is not particularly limited, but includes, for example, quaternary ammonium salts such as tetra-n-butylammonium bromide.

The resin composition used in this embodiment preferably contains the polyphenylene ether compound obtained as described above as the polyphenylene ether compound.

Examples of the radically polymerizable compounds (other radically polymerizable compounds) (A2) other than the polyphenylene ether compound include vinyl compounds, allyl compounds, methacrylate compounds, acrylate compounds, and acenaphthylene compounds.

The vinyl compound is a compound having a vinyl group in the molecule. Examples of the vinyl compound include monofunctional vinyl compounds (monovinyl compounds) having one vinyl group in the molecule, and polyfunctional vinyl compounds having two or more vinyl groups in the molecule. Examples of the monofunctional vinyl compound include styrene compounds and the like. Examples of the polyfunctional vinyl compound include polyfunctional aromatic vinyl compounds, vinyl hydrocarbon compounds, and the like. Furthermore, examples of the polyfunctional aromatic vinyl compound include divinylbenzene and the like. Furthermore, examples of the vinyl hydrocarbon compounds include polybutadiene compounds and the like.

The allyl compound is a compound having an allyl group in the molecule, and includes, for example, triallyl isocyanurate compounds such as triallyl isocyanurate (TAIC), diallyl bisphenol compounds, and diallyl phthalate (DAP).

The methacrylate compound is a compound having a methacryloyl group in the molecule, and includes, for example, a monofunctional methacrylate compound having one methacryloyl group in the molecule, and a polyfunctional methacrylate compound having two or more methacryloyl groups in the molecule. It will be done. Examples of the monofunctional methacrylate compound include methyl methacrylate, ethyl methacrylate, propyl methacrylate, and butyl methacrylate. Examples of the polyfunctional methacrylate compound include dimethacrylate compounds such as tricyclodecane dimethanol dimethacrylate (DCP).

The acrylate compound is a compound having an acryloyl group in the molecule, and includes, for example, a monofunctional acrylate compound having one acryloyl group in the molecule, and a polyfunctional acrylate compound having two or more acryloyl groups in the molecule. It will be done. Examples of the monofunctional acrylate compound include methyl acrylate, ethyl acrylate, propyl acrylate, and butyl acrylate. Examples of the polyfunctional acrylate compound include diacrylate compounds such as tricyclodecane dimethanol diacrylate.

The acenaphthylene compound is a compound having an acenaphthylene structure in its molecule. Examples of the acenaphthylene compound include acenaphthylene, alkylacenaphthylenes, halogenated acenaphthylenes, and phenylacenaphthylenes. Examples of the alkylacenaphthylenes include 1-methylacenaphthylene, 3-methylacenaphthylene, 4-methylacenaphthylene, 5-methylacenaphthylene, 1-ethylacenaphthylene, and 3-ethylacenaphthylene. Examples include phthylene, 4-ethylacenaphthylene, 5-ethylacenaphthylene, and the like. Examples of the halogenated acenaphthylenes include 1-chloroacenaphthylene, 3-chloroacenaphthylene, 4-chloroacenaphthylene, 5-chloroacenaphthylene, 1-bromoacenaphthylene, and 3-bromoacenaphthylene. Examples include ethylene, 4-bromoacenaphthylene, 5-bromoacenaphthylene, and the like. Examples of the phenylacenaphthylenes include 1-phenylacenaphthylene, 3-phenylacenaphthylene, 4-phenylacenaphthylene, and 5-phenylacenaphthylene. The acenaphthylene compound may be a monofunctional acenaphthylene compound having one acenaphthylene structure in the molecule, as described above, or a polyfunctional acenaphthylene compound having two or more acenaphthylene structures in the molecule. .

The radically polymerizable compound (A) may be composed of the polyphenylene ether compound (A1), or may be composed of the radically polymerizable compound (other radically polymerizable compound) other than the polyphenylene ether compound (A1) ( A2) may also be used. As described above, the radically polymerizable compound (A) preferably contains the polyphenylene ether compound (A1), and the polyphenylene ether compound (A1) and the other radically polymerizable compound (A2) are combined. It is more preferable to include.

Further, the other radically polymerizable compounds (A2) may be used alone or in combination of two or more. Among the above-mentioned radically polymerizable compounds, the other radically polymerizable compounds (A2) include polyfunctional aromatic vinyl compounds, allyl compounds, polyfunctional methacrylate compounds, polyfunctional acrylate compounds, polybutadiene compounds, acenaphthylene compounds, and styrene. Compounds etc. are preferred. Further, as the other radically polymerizable compound (A2), divinylbenzene and acenaphthylene are more preferable among the above-mentioned radically polymerizable compounds. deterioration can be suppressed more reliably.

The weight average molecular weight of the radically polymerizable compound (A) varies depending on the radically polymerizable compound (A) and is not particularly limited, but for example, it is preferably less than 10,000, and preferably from 500 to 5000. More preferred. When the radically polymerizable compound (A) is, for example, the polyphenylene ether compound (A1), its weight average molecular weight is preferably from 500 to 5,000, and preferably from 800 to 4,000, as described above. is more preferable, and even more preferably 1000 to 3000. Note that the weight average molecular weight here may be one measured by a general molecular weight measurement method, and specifically, a value measured using gel permeation chromatography (GPC), etc. can be mentioned.

When the radically polymerizable compound (A) contains the polyphenylene ether compound (A1), the content of the polyphenylene ether compound (A1) is 50 to 90 parts by mass based on 100 parts by mass of the radically polymerizable compound (A). Parts by mass are preferred. When the content of the polyphenylene ether compound (A1) is within the above range, the resin composition can be suitably cured, and the cured product has excellent low dielectric properties, adhesion to metal foil, and While maintaining flame retardancy, it is possible to increase thermal conductivity and suppress deterioration of withstand voltage after heat treatment and moisture absorption treatment. A more preferable range is 60 to 80 parts by mass.

(Phosphate ester compound (B))
The phosphoric ester compound (B) is not particularly limited as long as it is a phosphoric ester compound having an alicyclic hydrocarbon structure in its molecule. Since the phosphoric acid ester compound (B) is a phosphoric acid ester compound having an alicyclic hydrocarbon structure in its molecule, even if a compatible phosphorus flame retardant is used as a flame retardant, the cured product of the resin composition is It is possible to suppress the generation of phosphate ions due to heat treatment, suppress deterioration of withstand voltage after heat treatment and moisture absorption treatment, impart flame retardancy, and ensure low dielectric properties.

The alicyclic hydrocarbon structure is not particularly limited, and, for example, a 3- to 12-membered saturated alicyclic hydrocarbon structure is preferred, and a 5- to 7-membered saturated alicyclic hydrocarbon structure is more preferred. That is, the phosphoric acid ester compound (B) preferably contains a 3- to 12-membered saturated alicyclic hydrocarbon structure as the alicyclic hydrocarbon structure; More preferably, it contains a hydrocarbon structure. Examples of the alicyclic hydrocarbon structure include a divalent group of a saturated alicyclic hydrocarbon, which may have a substituent bonded to carbon forming the ring. Further, the alicyclic hydrocarbon structure may be a monocyclic alicyclic hydrocarbon structure or a polycyclic alicyclic hydrocarbon structure. Examples of the alicyclic hydrocarbon structure include divalent groups of cycloalkanes such as cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclononane, cyclodecane, cycloundecane, and cyclododecane. . Examples of the polycyclic alicyclic hydrocarbon structure include divalent groups of bicyclic alicyclic hydrocarbons and divalent groups of tricyclic alicyclic hydrocarbons. Examples of the divalent group of the bicyclic alicyclic hydrocarbon include bicyclo[1.1.0]butane, bicyclo[3.2.1]octane, bicyclo[5.2.0]nonane, and bicyclo [4.3.2] Divalent groups of bicyclic alicyclic hydrocarbons such as undecane and the like can be mentioned. Examples of the divalent group of the tricyclic alicyclic hydrocarbon include tricyclic alicyclic groups such as tricyclo[2.2.1.0]heptane and tricyclo[5.3.1.1]dodecane. Examples include divalent groups of formula hydrocarbons. The alicyclic hydrocarbon structure may be used alone or in combination of two or more. The substituent bonded to the carbon forming the ring is not particularly limited, and includes, for example, an alkyl group, an alkenyl group, an alkynyl group, a formyl group, an alkylcarbonyl group, an alkenylcarbonyl group, or an alkynylcarbonyl group, More specifically, the substituents listed below as R ₁ to R ₁₀ may be mentioned. These substituents may be used alone or in combination of two or more. That is, the number of substituents bonded to the carbon constituting the ring of the alicyclic hydrocarbon structure may be one, or two or more, and in the case of two or more, each substituent is , may be the same group or may be different groups. Furthermore, when there are two or more substituents, each of the substituents may be bonded to the same carbon among the carbons constituting the ring of the alicyclic hydrocarbon structure, or may be bonded to different carbon atoms. May be bonded to carbon.

Among the carbons constituting the ring of the alicyclic hydrocarbon structure, two bonds are formed on the same carbon, as in the divalent groups represented by the following formulas (15) to (18). or may be formed of different carbons.

More specifically, the alicyclic hydrocarbon structure includes divalent groups represented by the following formulas (15) to (18).

Examples of the phosphoric ester compound (B) include phosphoric ester compounds having at least one structure represented by the following formula (1) in the molecule. That is, examples of the phosphoric ester compound (B) include phosphoric ester compounds containing a structure represented by the following formula (1) as a structure containing phosphorus in the phosphoric ester compound (B). More specifically, examples of the phosphoric ester compound (B) include phosphoric ester compounds having the alicyclic hydrocarbon structure and a structure represented by the following formula (1) in the molecule.

In formula (1), R ₁ to R ₁₀ are each independent. That is, R ₁ to R ₁₀ may be the same group or different groups. Further, R ₁ to R ₁₀ 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.

The structure represented by the formula (1) is not particularly limited, but preferably has a substituent at the ortho position. Specifically, in the structure represented by formula (1), R ₁ , R ₅ , R ₆ , and R ₁₀ are atoms other than hydrogen atoms, that is, alkyl groups, alkenyl groups, alkynyl groups, formyl groups, and alkyl groups. A carbonyl group, an alkenylcarbonyl group, or an alkynylcarbonyl group, and in the structure represented by the above formula (1), a group other than R ₁ , R ₅ , R ₆ , and R ₁₀ (that is, R ₂ to R ₄ , and R ₇ to R ₉ ) are preferably hydrogen atoms. Specific examples of R ₁ to R ₁₀ in the formula (1) include the following groups.

The alkyl group is not particularly limited, and is preferably an alkyl group having 1 to 10 carbon atoms, more preferably an alkyl group having 1 to 6 carbon atoms, and even more preferably an alkyl group having 1 to 4 carbon atoms. Further, R ₁ , R ₅ , R ₆ and R ₁₀ are particularly preferably alkyl groups having 1 to 4 carbon atoms. The alkyl group may be linear or branched.

Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, n-pentyl group, isopentyl group, 2-methylbutyl group, 1- Methylbutyl group, 1,2-dimethylpropyl group, neopentyl group (2,2-dimethylpropyl group), tert-pentyl group (1,1-dimethylpropyl group), n-hexyl group, isohexyl group, 1-methylpentyl group , 2-methylpentyl group, 3-methylpentyl group, 1-ethylbutyl group, 2-ethylbutyl group, 1,1-dimethylbutyl group, 1,2-dimethylbutyl group, 1,3-dimethylbutyl group, 2,2 -dimethylbutyl group, 2,3-dimethylbutyl group, 1-ethyl-1-methylpropyl group, 1-ethyl-2-methylpropyl group, n-heptyl group, isoheptyl group, 1-methylhexyl group, 2-methyl Hexyl group, 3-methylhexyl group, 4-methylhexyl group, 1-ethylpentyl group, 2-ethylpentyl group, 3-ethylpentyl group, 1-propylbutyl group, 1,1-dimethylpentyl group, 1,2 -dimethylpentyl group, 1,3-dimethylpentyl group, 1,4-dimethylpentyl group, 1-ethyl-1-methylbutyl group, 1-ethyl-2-methylbutyl group, 1-ethyl-3-methylbutyl group, 2- Ethyl-1-methylbutyl group, 2-ethyl-1-methylbutyl group, 2-ethyl-2-methylbutyl group, 2-ethyl-3-methylbutyl group, 1,1-diethylpropyl group, n-octyl group, isooctyl group, 1-methylheptyl group, 2-methylheptyl group, 3-methylheptyl group, 4-methylheptyl group, 5-methylheptyl group, 1-ethylhexyl group, 2-ethylhexyl group, 3-ethylhexyl group, 4-ethylhexyl group, Examples include 1-propylheptyl group, 2-propylheptyl group, nonyl group, and decyl group. Among these, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, n-pentyl group, isopentyl group, 2-methylbutyl group, 1-methylbutyl group, 1, 2-dimethylpropyl group, neopentyl group (2,2-dimethylpropyl group), tert-pentyl group (1,1-dimethylpropyl group), n-hexyl group, isohexyl group, 1-methylpentyl group, 2-methylpentyl group group, 3-methylpentyl group, 1-ethylbutyl group, 2-ethylbutyl group, 1,1-dimethylbutyl group, 1,2-dimethylbutyl group, 1,3-dimethylbutyl group, 2,2-dimethylbutyl group, Alkyl groups having 1 to 6 carbon atoms such as 2,3-dimethylbutyl group, 1-ethyl-1-methylpropyl group, and 1-ethyl-2-methylpropyl group are more preferable, and methyl group, ethyl group, n- More preferred are alkyl groups having 1 to 4 carbon atoms such as propyl group, isopropyl group, n-butyl group, isobutyl group, and tert-butyl group.

The alkenyl group is not particularly limited, and is preferably an alkenyl group having 1 to 10 carbon atoms, more preferably an alkenyl group having 1 to 6 carbon atoms, and even more preferably an alkenyl group having 1 to 4 carbon atoms. Further, R ₁ , R ₅ , R ₆ and R ₁₀ are particularly preferably alkenyl groups having 1 to 4 carbon atoms. The alkenyl group may be linear or branched.

Examples of the alkenyl group include methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, tert-butoxy group, n-pentyloxy group, isopentyloxy group, 2-methyl Butoxy group, 1-methylbutoxy group, 1,2-dimethylpropoxy group, neopentyloxy group (2,2-dimethylpropoxy group), tert-pentyloxy group (1,1-dimethylpropoxy group), n-hexyloxy group, isohexyloxy group, 1-methylpentyloxy group, 2-methylpentyloxy group, 3-methylpentyloxy group, 1-ethylbutoxy group, 2-ethylbutoxy group, 1,1-dimethylbutoxy group, 1, 2-dimethylbutoxy group, 1,3-dimethylbutoxy group, 2,2-dimethylbutoxy group, 2,3-dimethylbutoxy group, 1-ethyl-1-methylpropoxy group, 1-ethyl-2-methylpropoxy group, n-heptyloxy group, isoheptyloxy group, 1-methylhexyloxy group, 2-methylhexyloxy group, 3-methylhexyloxy group, 4-methylhexyloxy group, 1-ethylpentyloxy group, 2-ethylpentyl group Oxy group, 3-ethylpentyloxy group, 1-propylbutoxy group, 1,1-dimethylpentyloxy group, 1,2-dimethylpentyloxy group, 1,3-dimethylpentyloxy group, 1,4-dimethylpentyloxy group group, 1-ethyl-1-methylbutoxy group, 1-ethyl-2-methylbutoxy group, 1-ethyl-3-methylbutoxy group, 2-ethyl-1-methylbutoxy group, 2-ethyl-1-methylbutoxy group group, 2-ethyl-2-methylbutoxy group, 2-ethyl-3-methylbutoxy group, 1,1-diethylpropoxy group, n-octyloxy group, isooctyloxy group, 1-methylheptyloxy group, 2- Methylheptyloxy group, 3-methylheptyloxy group, 4-methylheptyloxy group, 5-methylheptyloxy group, 1-ethylhexyloxy group, 2-ethylhexyloxy group, 3-ethylhexyloxy group, 4-ethylhexyloxy group, Examples include 1-propylheptyloxy group, 2-propylheptyloxy group, nonyloxy group, and decyloxy group. Among these, methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, tert-butoxy group, n-pentyloxy group, isopentyloxy group, 2-methylbutoxy group, 1- Methylbutoxy group, 1,2-dimethylpropoxy group, neopentyloxy group (2,2-dimethylpropoxy group), tert-pentyloxy group (1,1-dimethylpropoxy group), n-hexyloxy group, isohexyloxy group group, 1-methylpentyloxy group, 2-methylpentyloxy group, 3-methylpentyloxy group, 1-ethylbutoxy group, 2-ethylbutoxy group, 1,1-dimethylbutoxy group, 1,2-dimethylbutoxy group , 1,3-dimethylbutoxy group, 2,2-dimethylbutoxy group, 2,3-dimethylbutoxy group, 1-ethyl-1-methylpropoxy group, and 1-ethyl-2-methylpropoxy group with 1 carbon number -6 alkenyl groups are more preferred, and alkenyl groups having 1 to 4 carbon atoms such as methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, and tert-butoxy are even more preferred. .

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

The structure represented by the formula (1) includes any one of a hydrogen atom, the alkyl group, the alkenyl group, the alkynyl group, the formyl group, the alkylcarbonyl group, the alkenylcarbonyl group, and the alkynylcarbonyl group. It may have seeds or a combination of two or more types.

Further, the phosphoric ester compound (B) includes a phosphoric ester compound having a structure represented by the following formula (2), and preferably contains this phosphoric ester compound.

In formula (2), Ar ₁ and Ar ₂ each independently represent an arylene group. T represents a divalent group of a 3- to 12-membered saturated alicyclic hydrocarbon.

The arylene group is not particularly limited. Examples of the arylene group include monocyclic aromatic groups such as a phenylene group, and polycyclic aromatic groups such as a naphthalene ring. Examples of the arylene group include a group represented by the following formula (19).

In formula (19), R ₄₅ to R ₄₈ are each independent. That is, R ₄₅ to R ₄₈ may be the same group or different groups. Furthermore, R ₄₅ to R ₄₈ 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.

Examples of R ₄₅ to R ₄₈ in the formula (19) include the same groups as R ₁ to R ₁₀ in the formula (1).

Further, more specific examples of the phosphoric ester compound having the structure represented by the above formula (2) include, for example, the phosphoric ester compound represented by the following formula (20).

In formula (20), R ₄₉ to R ₆₈ are each independent. That is, R ₄₉ to R ₆₈ may be the same group or different groups. Further, R ₄₉ to R ₆₈ in the above formula (20) include the same groups as R ₁ to R ₁₀ in the above formula (1), such as a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, a formyl group, and an alkyl group. Indicates a carbonyl group, alkenylcarbonyl group, or alkynylcarbonyl group. Moreover, Ar ₁ , Ar ₂ and T are the same as Ar ₁ , Ar ₂ and T in the above formula (2).

More specific examples of the phosphoric acid ester compound (B) include, for example, compounds represented by the following formulas (21) to (24).

The phosphoric acid ester compound (B) may be used alone or in combination of two or more.

The method for producing the phosphoric ester compound (B) is not particularly limited as long as the phosphoric ester compound (B) can be produced, and any known method can be used. Examples of the method for producing the phosphoric acid ester compound (B) include a method using phosphoryl chloride (phosphorus oxychloride).

The content of the phosphoric acid ester compound (B) is preferably 15 to 50 parts by mass, more preferably 15 to 35 parts by mass, based on 100 parts by mass of the radically polymerizable compound (A). , more preferably 15 to 25 parts by mass.

If the content of the phosphoric acid ester compound (B) is too low, the obtained cured product tends to have insufficient flame retardancy. Moreover, when the content of the phosphoric acid ester compound (B) is too large, the content of the radically polymerizable compound (A) becomes relatively too small, and after heat treatment and moisture absorption treatment of the obtained cured product, The withstand voltage tends to deteriorate. From these facts, when the content of the phosphoric acid ester compound (B) is 15 to 50 parts by mass with respect to 100 parts by mass of the radically polymerizable compound (A), heat treatment and moisture absorption treatment in the cured product are possible. A resin composition that can exhibit sufficient flame retardancy while suppressing subsequent deterioration of withstand voltage can be obtained.

Note that the resin composition may contain a flame retardant other than the phosphoric acid ester compound (B).

(Incompatible phosphorus compound (D))
It is preferable that the resin composition further includes the incompatible phosphorus compound (D). That is, it is preferable that the resin composition contains the phosphoric acid ester compound (B) and the incompatible phosphorus compound (D) as compounds that can act as a flame retardant. By using the phosphoric acid ester compound (B) and the incompatible phosphorus compound (D) together, in the cured product of the resin composition, flame retardance is ensured while reducing adhesion to the metal foil. Can be suppressed.

The incompatible phosphorus compound (D) is not particularly limited as long as it acts as a flame retardant and is incompatible with the mixture. Here, the term "incompatible" refers to a state in which the target substance (phosphorus compound) is not compatible with the radically polymerizable compound (A) and is dispersed in the form of islands in the mixture. Examples of the incompatible phosphorus compound (D) include compounds containing phosphorus and forming salts, such as phosphinate compounds, polyphosphate compounds, and phosphonium salt compounds, and phosphine oxide compounds. In addition, examples of phosphinate compounds include aluminum dialkylphosphinate, aluminum trisdiethylphosphinate, aluminum trismethylethylphosphinate, aluminum trisdiphenylphosphinate, zinc bisdiethylphosphinate, zinc bismethylethylphosphinate, and bisdiphenyl. Zinc phosphinate, titanyl bisdiethylphosphinate, titanyl bismethylethylphosphinate, titanyl bisdiphenylphosphinate, and the like. Examples of the polyphosphate compound include melamine polyphosphate, melam polyphosphate, and melem polyphosphate. Further, examples of the phosphonium salt compound include tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium bromide, and the like. Examples of phosphine oxide compounds include phosphine oxide compounds having two or more diphenylphosphine oxide groups in the molecule (diphenylphosphine oxide compounds), and more specifically, paraxylylenebisdiphenylphosphine oxide, etc. can be mentioned. Further, the above-mentioned incompatible phosphorus compounds may be used alone or in combination of two or more.

In the present embodiment, the content of the phosphoric acid ester compound (B) is 25 to 100 parts by mass based on a total of 100 parts by mass of the phosphoric acid ester compound (B) and the incompatible phosphorus compound (D). parts, more preferably 25 to 75 parts by weight, and most preferably 25 to 50 parts by weight.

The content of the phosphoric acid ester compound (B) is 25 to 100 parts by mass based on the total of 100 parts by mass of the phosphoric acid ester compound (B) and the incompatible phosphorus compound (D), It is possible to obtain a cured product that has excellent adhesion to metal foil while ensuring flame retardancy.

(Inorganic filler (C))
The resin composition according to this embodiment further contains an inorganic filler (C). The inorganic filler (C) is not particularly limited as long as it can be used as an inorganic filler contained in a resin composition, but examples include boron nitride filler, silica filler, aluminum oxide filler, titanium oxide filler, and titanium oxide filler. Metal oxide fillers such as magnesium fillers and mica fillers, aluminum hydroxide fillers, and metal hydroxide fillers such as magnesium hydroxide fillers, talc fillers, aluminum borate fillers, barium sulfate fillers, aluminum nitride fillers, silicon nitride fillers, Examples include magnesium carbonate fillers such as anhydrous magnesium carbonate fillers, calcium carbonate fillers, and the like.

The boron nitride filler is not particularly limited, and examples include hexagonal normal pressure phase (h-BN) filler, cubic high pressure phase (c-BN) filler, and the like. Further, the silica filler is not particularly limited, and examples thereof include crushed silica filler and silica particle filler, and silica particle filler is preferable. Further, examples of the silica particle filler include crystalline silica filler, amorphous silica filler, fused silica filler, precipitated silica filler, etc., and fused silica filler is preferable. The magnesium carbonate filler is not particularly limited, but anhydrous magnesium carbonate (synthetic magnesite) filler is preferable.

These inorganic fillers may be used alone or in combination of two or more.

In addition, the inorganic fillers as exemplified above include an inorganic filler (C-1) with a thermal conductivity of 10 W/m・K or more and an inorganic filler (C-1) with a thermal conductivity of less than 10 W/m・K. The inorganic filler (C) preferably includes an inorganic filler (C-1) having a thermal conductivity of 10 W/m·K or more. It is thought that this makes it possible to more reliably achieve high thermal conductivity in the cured product of the resin composition. In addition, the inorganic filler (C) includes an inorganic filler (C-1) with a thermal conductivity of 10 W/m·K or more, and an inorganic filler (C-2) with a thermal conductivity of less than 10 W/m·K. ). By using the inorganic filler (C-1) and the inorganic filler (C-2) together as the inorganic filler (C), it is possible to ensure adhesion to the metal foil and to achieve high filling of the inorganic filler. This has the advantage that deterioration of withstand voltage after heat treatment and moisture absorption treatment due to chemical reaction can be suppressed.

Examples of the inorganic filler (C-1) include boron nitride filler, aluminum oxide filler, magnesium oxide filler, magnesium carbonate filler, silicon nitride filler, aluminum nitride filler, and the like. Among these, as the inorganic filler (C-1), boron nitride filler, aluminum oxide filler, magnesium oxide filler, and magnesium carbonate filler are preferable, and boron nitride filler is more preferable. The inorganic filler (C-1) contains a boron nitride filler, that is, the inorganic filler (C) contains a boron nitride filler, thereby ensuring low dielectric properties in the cured product of the resin composition. The heat dissipation properties of a cured product and a substrate such as a wiring board using the cured product can be improved. As the inorganic filler (C-1), the inorganic fillers exemplified above may be used alone or in combination of two or more.

Examples of the inorganic filler (C-2) include fused silica filler, magnesium hydroxide filler, mica filler, and the like. Among these, fused silica filler is preferable as the inorganic filler (C-2). As the inorganic filler (C-2), the inorganic fillers exemplified above may be used alone or in combination of two or more.

The inorganic filler (C) may be a surface-treated inorganic filler or may be a surface-untreated inorganic filler. Furthermore, examples of the surface treatment include treatment with a silane coupling agent.

Examples of the silane coupling agent include a silane coupling agent 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, this silane coupling agent has at least one of a vinyl group, a styryl group, a methacryloyl group, an acryloyl group, and a phenylamino group as a reactive functional group, and also has a methoxy group, an ethoxy group, etc. Examples include compounds having a hydrolyzable group.

The silane coupling agent has a vinyl group, and examples thereof include vinyltriethoxysilane and vinyltrimethoxysilane. The silane coupling agent has a styryl group, and examples thereof include p-styryltrimethoxysilane and p-styryltriethoxysilane. The silane coupling agent has a methacryloyl group, and examples thereof include 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, and 3-methacryloxypropylethyldiethoxysilane. The silane coupling agent has an acryloyl group, and examples thereof include 3-acryloxypropyltrimethoxysilane and 3-acryloxypropyltriethoxysilane. Examples of the silane coupling agent that has a phenylamino group include N-phenyl-3-aminopropyltrimethoxysilane and N-phenyl-3-aminopropyltriethoxysilane.

The content of the inorganic filler (C) is preferably 100 to 380 parts by mass based on 100 parts by mass of the radically polymerizable compound (A). Thereby, in the cured product of the resin composition, deterioration of withstand voltage after heat treatment and moisture absorption treatment can be more reliably suppressed. The content of the inorganic filler (C) is more preferably 200 to 380 parts by mass, and even more preferably 300 to 380 parts by mass, based on 100 parts by mass of the radically polymerizable compound (A). .

Further, when the inorganic filler (C) includes an inorganic filler (C-1) having a thermal conductivity of 10 W/m·K or more, the inorganic filler (C-1) is The content of the filler (C-1) is preferably 25 to 100 parts by mass. It is thought that this makes it possible to more reliably achieve high thermal conductivity in the cured product of the resin composition.

When the inorganic filler (C-1) contains a boron nitride filler, that is, when the inorganic filler (C) contains a boron nitride filler, the content of the boron nitride filler is the same as that of the inorganic filler (C). The amount is preferably 25 to 100 parts by weight per 100 parts by weight. It is thought that this makes it possible to more reliably achieve high thermal conductivity in the cured product of the resin composition. The content of the boron nitride filler is more preferably 25 to 70 parts by mass, and even more preferably 30 to 50 parts by mass, based on 100 parts by mass of the inorganic filler (C).

Furthermore, the inorganic filler (C) includes an inorganic filler (C-1) having a thermal conductivity of 10 W/m·K or more, and an inorganic filler (C-2) having a thermal conductivity of less than 10 W/m·K. ), the content of the inorganic filler (C-1) is 25 parts by mass based on a total of 100 parts by mass of the inorganic filler (C-1) and the inorganic filler (C-2). The amount is preferably 70 parts by mass. Thereby, in the cured product of the resin composition, deterioration of withstand voltage after heat treatment and moisture absorption treatment can be more reliably suppressed. The content of the inorganic filler (C-1) is 25 to 50 parts by mass based on a total of 100 parts by mass of the inorganic filler (C-1) and the inorganic filler (C-2). The amount is more preferably 25 to 40 parts by mass.

In the inorganic filler (C) of the present embodiment, in the particle size distribution of the inorganic filler (C), the peak of the particle size distribution measured by laser diffraction particle size distribution measuring method is 1.0 to 50.0 μm. It is preferable that at least two of them exist in the range of . That is, in the inorganic filler used in this embodiment, it is preferable that inorganic fillers having at least two types of peak particle sizes (peak tops) are mixed. By using an inorganic filler having at least two peaks within the above particle size range, high thermal conductivity and low dielectric properties (Dk) can be achieved in the cured product of the resin composition.

Furthermore, it is preferable that at least one peak exists in the particle size range of 1.0 to 5.0 μm and at least one peak exists in the particle size range of 5.0 to 50.0 μm. In other words, the inorganic fillers used in a more preferred embodiment include an inorganic filler with a relatively small particle size, an inorganic filler with a relatively large particle size, and an inorganic filler with at least two types of peak particle sizes (peak tops). Fillers are mixed. It is thought that this makes it possible to ensure both adhesion with the metal foil and high thermal conductivity.

In this specification, the particle size distribution is a value measured by particle size distribution measurement using a laser diffraction/scattering method. For example, the particle size distribution measuring device "LA-960V2" used in the examples described below (manufactured by Horiba, Ltd.), etc. Furthermore, in the present embodiment, the peak refers to the maximum value in a particle size distribution graph, and specifically, in a particle size distribution graph where the horizontal axis is the particle diameter and the vertical axis is the relative particle amount (frequency). This is the numerical value obtained by the maximum value of .

(Other ingredients)
The resin composition according to the present embodiment may contain components other than the above-mentioned components (other components), as necessary, within a range that does not impair the effects of the present invention. Other components contained in the resin composition according to the present embodiment include, for example, a styrene polymer, a free radical compound, a reaction initiator, a silane coupling agent, an antifoaming agent, an antioxidant, a heat stabilizer, It may further contain additives such as antistatic agents, ultraviolet absorbers, dyes and pigments, dispersants, and lubricants. In addition to the radically polymerizable compound (A), the resin composition of the present embodiment also contains a thermosetting resin such as an epoxy resin, a maleimide resin, an aromatic hydrocarbon resin, and an aliphatic hydrocarbon resin. Good too.

- Styrenic polymer The resin composition of the present embodiment may further contain a styrene polymer in addition to the components described above. It is thought that the resin composition containing the styrene polymer has the advantage of further lowering the dielectric constant of the resin.

The styrenic polymer used in this embodiment is, for example, a polymer obtained by polymerizing a monomer containing a styrene monomer, and may be a styrene copolymer. The styrenic copolymer is, for example, a copolymer of one or more styrene monomers and one or more other monomers copolymerizable with the styrene monomer. Examples include the resulting copolymers. Examples of the styrene monomer include styrene, styrene derivatives, and styrene in which some of the hydrogen atoms are substituted with substituents.

As a specific styrenic polymer, a wide variety of conventionally known polymers can be used, and is not particularly limited. Examples include polymers having the following.

In formula (25), R ₆₉ to R ₇₁ each independently represent a hydrogen atom or an alkyl group, and R ₇₂ is selected from the group consisting of a hydrogen atom, an alkyl group, an alkenyl group, and an isopropenyl group. Indicates the group. The alkyl group is not particularly limited, and, for example, an alkyl group having 1 to 18 carbon atoms is preferable, and an alkyl group having 1 to 10 carbon atoms is more preferable. Further, the alkenyl group is preferably an alkenyl group having 1 to 10 carbon atoms. Specific examples include methyl group, ethyl group, propyl group, hexyl group, and decyl group.

The styrenic polymer of this embodiment preferably contains at least one type of structural unit represented by the above formula (25), but may contain a combination of two or more different types. Moreover, it is preferable that the styrenic polymer includes a structure in which structural units represented by the above formula (25) are repeated.

Preferred examples of styrenic polymers include those obtained by polymerizing or copolymerizing one or more styrene monomers such as styrene, vinyltoluene, α-methylstyrene, isopropenyltoluene, divinylbenzene, and allylstyrene. Examples include polymers or copolymers, and more specific examples include styrene-butadiene copolymers, styrene-isobutylene copolymers, and the like. Further, the styrenic polymer may be a hydrogenated styrene polymer, such as 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, and hydrogenated styrene (ethylene-ethylene/propylene) Examples include styrene copolymers.

Note that, as the styrene-based polymer, those exemplified above may be used alone, or two or more types may be used in combination.

By including such a styrene polymer, in addition to the above-mentioned effects, the moisture absorption rate of the cured product of the resin composition can be suppressed, and the deterioration of electrical properties due to an increase in the amount of moisture absorption can be suppressed. It can also be effective.

In the case where the styrenic polymer of the preferred embodiment contains at least one type of structural unit represented by the above formula (25), the molar fraction of the structural unit is about 10 to 70% with respect to the entire polymer. It is preferably 15% to 65%, more preferably 15% to 65%. As a result, compatibility with the resin can be maintained, resulting in the further advantage that uniformity of properties within the resin composition can be maintained.

The polymerization form of the styrenic polymer is not particularly limited, and may be a block copolymer, an alternating copolymer, a random copolymer, a graft copolymer, or the like. It may also be in the form of an elastomer.

The weight average molecular weight of the styrenic polymer of this embodiment is preferably about 10,000 to 200,000, more preferably about 20,000 to 150,000. When the weight average molecular weight is within the above range, there is an advantage that appropriate resin fluidity can be ensured in the B stage of the cured resin product. Note that the number average molecular weight here may be one measured by a general molecular weight measurement method, and specifically, a value measured using gel permeation chromatography, etc. can be mentioned.

In a preferred embodiment, the styrenic polymer more desirably includes a styrene-isobutylene-styrene block copolymer (SIBS) containing a structural unit represented by the following formula (26). Thereby, it becomes possible to obtain a resin composition with high gas barrier properties, and there is an advantage that moisture absorption into the resin composition can be suppressed.

In formula (26), the sum of a1, a2 represents an integer of 1,000 to 60,000, b represents an integer of 1,000 to 70,000, and the sum of a1, a2 and b is 10, 000 to 130,000.

Although the method for producing the styrenic polymer used in this embodiment is not particularly limited, for example, to show an example of the method for producing the SIBS, first, isobutylene is polymerized by a living cationic polymerization method, and then styrene is added. It can be synthesized by polymerization.

The styrenic polymer of this embodiment can be a commercially available one, such as "SIBSTAR (registered trademark) 073T", "SIBSTAR (registered trademark) 103T", "SIBSTAR (registered trademark)" manufactured by Kaneka Corporation. ) 102T" and "Septon V9827" manufactured by Kuraray Co., Ltd..

When the resin composition of the present embodiment contains the styrenic polymer, the content of the styrene polymer is not particularly limited, but is 1 to 30 parts by mass based on 100 parts by mass of the radically polymerizable compound (A). It is preferably 1 to 20 parts by weight, more preferably 1 to 15 parts by weight. When the content of the styrene polymer is 30 parts by mass or less based on 100 parts by mass of the radically polymerizable compound (A), the cured product of the resin composition has excellent moldability and flame retardancy. is more reliably obtained, and by using 1 part by mass or more, low dielectric properties can be more reliably ensured in the cured product of the resin composition.

-Free radical compound The resin composition of this embodiment may contain a free radical compound. It is thought that the inclusion of the free radical compound in the resin composition has the advantage of improving the flowability of the resin and improving the moldability. The free radical compound is not particularly limited as long as it is a free radical compound used as a polymerization inhibitor.

More specific free radical compounds that can be preferably used in this embodiment include 4-amino-2,2,6,6-tetramethylpiperidine 1-oxyl free radical, 4-acetamido-2,2,6, 6-tetramethylpiperidine 1-oxyl free radical, 4-amino-2,2,6,6-tetramethylpiperidine 1-oxyl free radical, 4-carboxy-2,2,6,6-tetramethylpiperidine 1-oxyl Free radical, 4-cyano-2,2,6,6-tetramethylpiperidine 1-oxyl free radical, 4-glycidyloxy-2,2,6,6-tetramethylpiperidine 1-oxyl free radical, 4-hydroxy- 2,2,6,6-tetramethylpiperidine 1-oxyl free radical, 4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxylbenzoate free radical, 4-isothiocyanato-2,2,6, 6-tetramethylpiperidine 1-oxyl free radical, 4-(2-iodoacetamido)-2,2,6,6-tetramethylpiperidine 1-oxyl free radical, 4-[2-[2-(4-iodophenoxy) ) Ethoxy]carbonyl]benzoyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl, 4-methoxy-2,2,6,6-tetramethylpiperidine-1-oxyl free radical, 4-methacryloyloxy- 2,2,6,6-tetramethylpiperidine 1-oxyl free radical, 4-oxo-2,2,6,6-tetramethylpiperidine 1-oxyl free radical, 4-oxo-2,2,6,6- Tetramethylpiperidine 1-oxyl free radical, 2,2,6,6-tetramethylpiperidine 1-oxyl free radical, 2,2,6,6-tetramethyl-4-(2-propynyloxy)piperidine 1-oxyl free Radical, 2,2,6,6-tetramethylpiperidine-1-oxyl Free radical, 4,5-dihydro-4,4,5,5-tetramethyl-2-phenyl-1H-imidazol-1-yloxy-1- oxide, sebacate bis(2,2,6,6-tetramethyl-4-piperidyl-1-oxyl), 3-carboxy-2,2,5,5-tetramethylpyrrolidine 1-oxyl free radical, 4-( 2-chloroacetamido)-2,2,6,6-tetramethylpiperidine 1-oxyl free radical, 2-(4-nitrophenyl)-4,4,5,5-tetramethylimidazoline-3-oxide-1- Oxyl free radical, 2-(14-carboxytetradecyl)-2-ethyl-4,4-dimethyl-3-oxazolidinyloxy free radical, 1,1-diphenyl-2-picrylhydrazyl free radical, etc. Can be mentioned. These may be used alone or in combination of two or more. Commercially available free radical compounds such as those described above can also be used, and are available from Tokyo Chemical Industry Co., Ltd., for example.

When the resin composition of the present embodiment contains the free radical compound, the content of the free radical compound is not particularly limited, but is 0.01 to 0.0 with respect to 100 parts by mass of the radically polymerizable compound (A). The amount is preferably 0.1 part by weight, and more preferably 0.01 to 0.05 part by weight.

- Reaction initiator As described above, the resin composition according to the present embodiment may contain a reaction initiator (initiator). Even if the resin composition contains, for example, the polyphenylene ether compound and the curing agent, the curing reaction can proceed. However, depending on the process conditions, it may be difficult to raise the temperature to a high temperature until curing progresses, so a reaction initiator may be added.

The reaction initiator is not particularly limited as long as it can promote the curing reaction of the resin composition. Specific examples include metal oxides, azo compounds, and organic peroxides.

Specific examples of the metal oxide include carboxylic acid metal salts.

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, azobisisobutyronitrile, etc. can be mentioned.

Specifically, the azo compounds include 2,2'-azobis(2,4,4-trimethylpentane), 2,2'-azobis(N-butyl-2-methylpropionamide), 2,2'- Examples include azobis(2-methylbutyronitrile).

Among these, preferred reaction initiators are 2,2'-azobis(2,4,4-trimethylpentane), 2,2'-azobis(N-butyl-2-methylpropionamide), and the like. These reaction initiators have little effect on dielectric properties. In addition, since the reaction initiation temperature is relatively high, it is possible to suppress the acceleration of the curing reaction at a time when curing is not necessary, such as when drying the prepreg, and it is possible to suppress a decrease in the storage stability of the resin composition. This is because it has the advantage of being possible.

The reaction initiators as described above may be used alone or in combination of two or more.

When the resin composition of the present embodiment contains the reaction initiator, the content thereof is not particularly limited, but is 0.5 to 3 parts by mass based on 100 parts by mass of the radically polymerizable compound (A). The amount is preferably 0.5 to 2 parts by mass, and more preferably 0.5 to 2 parts by mass.

- Silane coupling agent As mentioned above, the resin composition according to this embodiment may contain a silane coupling agent. The silane coupling agent may be contained in the resin composition as it is, or may be contained as a silane coupling agent used when surface-treating the inorganic filler in advance. Among these, the silane coupling agent is preferably contained as a silane coupling agent used when surface-treating the inorganic filler in advance. Moreover, it is more preferable that the silane coupling agent is contained as a silane coupling agent used when surface-treating the inorganic filler in advance, and that the silane coupling agent is further contained in the resin composition as it is. Further, in the case of prepreg, the prepreg may contain a silane coupling agent used when surface-treating the fibrous base material in advance. Examples of the silane coupling agent include those similar to the silane coupling agents described above used when surface treating the inorganic filler.

When the resin composition of the present embodiment contains a silane coupling agent, its content is not particularly limited, but it should be 1 to 6 parts by mass based on 100 parts by mass of the radically polymerizable compound (A). The amount is preferably 2 to 5 parts by mass, and more preferably 2 to 5 parts by mass.

(Application)
The resin composition is used when manufacturing prepreg, as described below. Further, the resin composition is used when forming a resin layer included in a resin-coated metal foil and a resin-coated film, and an insulating layer included in a metal-clad laminate and a wiring board. Further, as described above, the resin composition provides a cured product having excellent low dielectric properties such as a low relative dielectric constant. Therefore, the resin composition is suitably used to form an insulating layer included in a high frequency compatible wiring board such as a wiring board for an antenna or an antenna substrate for millimeter wave radar. That is, the resin composition is suitable for manufacturing wiring boards compatible with high frequencies.

(Production method)
The method for producing the resin composition is not particularly limited, and for example, the radically polymerizable compound (A) and the phosphoric acid ester compound (B) are mixed with other organic components as necessary, and then , a method of adding the inorganic filler (C), and the like. Specifically, in the case of obtaining a varnish-like composition containing an organic solvent, the method described in the explanation of the prepreg mentioned later may be used.

Next, prepregs, metal-clad laminates, wiring boards, resin-coated metal foils, and resin-coated films using the resin composition according to the present embodiment will be described with reference to the drawings. In addition, in each drawing, each code|symbol is 1: prepreg, 2: resin composition or semi-cured product of a resin composition, 3: fibrous base material, 11: metal-clad laminate, 12: insulating layer, 13: metal Foil, 14: Wiring, 21: Wiring board, 31: Metal plate with resin, 32 and 42: Resin layer, 41: Film with resin, 43: Support film.

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

As shown in FIG. 1, the prepreg 1 according to the present embodiment includes the resin composition or a semi-cured product 2 of the resin composition, and a fibrous base material 3. This prepreg 1 includes the resin composition or a semi-cured product 2 of the resin composition, and a fibrous base material 3 present in the resin composition or the semi-cured product 2 of the resin composition.

Note that in this embodiment, the semi-cured product is a state in which the resin composition is partially cured to the extent that it can be further cured. That is, the semi-cured product is a semi-cured (B-staged) resin composition. For example, when a resin composition is heated, the viscosity first gradually decreases, and then curing starts and the viscosity gradually increases. In such a case, semi-curing includes a state between when the viscosity begins to rise and before it is completely cured.

Further, the prepreg obtained using the resin composition according to the present embodiment may include a semi-cured product of the resin composition as described above, or may include the uncured resin composition. It may also include the composition itself. That is, it may be a prepreg comprising a semi-cured product of the resin composition (the resin composition at the B stage) and a fibrous base material, or a prepreg comprising the semi-cured product of the resin composition (the resin composition at the A stage), or a prepreg comprising the resin composition before curing (the resin composition at the A stage). It may be a prepreg comprising a material) and a fibrous base material. Further, the resin composition or the semi-cured product of the resin composition may be one obtained by drying or heating drying the resin composition.

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

First, each component of the resin composition that can be dissolved in an organic solvent is poured into an organic solvent and dissolved therein. At this time, heating may be performed if necessary. After that, components that do not dissolve in organic solvents (for example, inorganic fillers, etc.) are added as necessary, and dispersed using a ball mill, bead mill, planetary mixer, roll mill, etc. until a predetermined dispersion state is achieved. By doing so, a varnish-like resin composition is prepared. The organic solvent used here is not particularly limited as long as it dissolves the modified polyphenylene ether compound, the curing agent, etc. and does not inhibit the curing reaction. Specific examples include toluene and methyl ethyl ketone (MEK).

The method for manufacturing the prepreg is not particularly limited as long as the prepreg can be manufactured. Specifically, when manufacturing a prepreg, the resin composition used in this embodiment described above is often prepared in the form of a varnish and used as a resin varnish, as described above.

Specific examples of the fibrous base material include glass cloth, aramid cloth, polyester cloth, glass nonwoven fabric, aramid nonwoven fabric, polyester nonwoven fabric, pulp paper, and linter paper. Note that when glass cloth is used, a laminate with excellent mechanical strength can be obtained, and glass cloth that has been flattened is particularly preferred. Specifically, the flattening process includes, for example, a method in which a glass cloth is continuously pressed with a press roll at an appropriate pressure to compress the yarn into a flat shape. Note that the thickness of the commonly used fibrous base material is, for example, 0.01 mm or more and 0.3 mm or less.

The method for manufacturing the prepreg is not particularly limited as long as the prepreg can be manufactured. Specifically, when manufacturing a prepreg, the resin composition according to the present embodiment described above is often prepared in the form of a varnish and used as a resin varnish, as described above.

Examples of the method for manufacturing the prepreg 1 include a method in which the fibrous base material 3 is impregnated with the resin composition 2, for example, the resin composition 2 prepared in the form of a varnish, and then dried. The resin composition 2 is impregnated into the fibrous base material 3 by dipping, coating, or the like. It is also possible to repeat the impregnation multiple times if necessary. Further, at this time, by repeating impregnation using a plurality of resin compositions having different compositions and concentrations, it is possible to finally adjust the desired composition and impregnation amount.

The fibrous base material 3 impregnated with the resin composition (resin varnish) 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. By heating, prepreg 1 in a pre-cured (A stage) or semi-cured state (B stage) is obtained. In addition, by the heating, the organic solvent can be volatilized from the resin varnish, and the organic solvent can be reduced or removed.

The resin composition according to the present embodiment or the prepreg comprising the semi-cured product of this resin composition has low dielectric properties (relative permittivity), excellent adhesion with metal foil and flame retardancy, and high thermal conductivity. This is a prepreg from which a cured product with suppressed deterioration of withstand voltage after heat treatment and moisture absorption treatment can be obtained.

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

As shown in FIG. 2, the metal-clad laminate 11 is composed of an insulating layer 12 containing a cured product of the prepreg 1 shown in FIG. has been done. That is, the metal-clad laminate 11 includes an insulating layer 12 containing a cured resin composition and a metal foil 13 provided on the insulating layer 12. Further, the insulating layer 12 may be made of a cured product of the resin composition, or may be made of a cured product of the prepreg. Further, the thickness of the metal foil 13 is not particularly limited and varies depending on the performance required of the ultimately obtained wiring board. The thickness of the metal foil 13 can be appropriately set depending on the desired purpose, and is preferably 0.2 to 70 μm, for example. Further, examples of the metal foil 13 include copper foil and aluminum foil, and when the metal foil is thin, it may be a carrier-attached copper foil provided with a peeling layer and a carrier to improve handling properties. Good too.

The method for manufacturing the metal-clad laminate 11 is not particularly limited as long as the metal-clad laminate 11 can be manufactured. Specifically, a method of producing the metal-clad laminate 11 using the prepreg 1 can be mentioned. This method involves stacking one or more prepregs 1, then stacking a metal foil 13 such as copper foil on both or one side of the top and bottom, and forming the metal foil 13 and the prepreg 1 under heat and pressure to form an integrated laminate. By doing so, a method of producing a laminate 11 with metal foil on both sides or with metal foil on one side can be mentioned. That is, the metal-clad laminate 11 is obtained by laminating the metal foil 13 on the prepreg 1 and molding it under heat and pressure. Further, the heating and pressing conditions can be appropriately set depending on the thickness of the metal-clad laminate 11 to be manufactured, the type of composition of the prepreg 1, and the like. For example, the temperature can be 170 to 220°C, the pressure can be 3 to 4 MPa, and the time can be 60 to 150 minutes. Further, the metal-clad laminate may be manufactured without using prepreg. For example, a method may be used in which a varnish-like resin composition is applied onto a metal foil, a layer containing the resin composition is formed on the metal foil, and then heated and pressed.

The metal-clad laminate including the insulating layer containing the cured product of the resin composition according to the present embodiment has low dielectric properties (relative permittivity), excellent adhesion with metal foil and flame retardancy, and high thermal conductivity. This is a metal-clad laminate including an insulating layer that is high in voltage and has suppressed deterioration of withstand voltage after heat treatment and moisture absorption treatment.

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

As shown in FIG. 3, the wiring board 21 according to the present embodiment includes an insulating layer 12 used by curing the prepreg 1 shown in FIG. The wiring 14 is formed by partially removing the foil 13. That is, the wiring board 21 has an insulating layer 12 containing a cured resin composition, and wiring 14 provided on both or one side of the upper and lower sides of the insulating layer 12. Further, the insulating layer 12 may be made of a cured product of the resin composition, or may be made of a cured product of the prepreg.

The method for manufacturing the wiring board 21 is not particularly limited as long as the wiring board 21 can be manufactured. Specifically, a method of manufacturing the wiring board 21 using the prepreg 1 may be mentioned. In this method, for example, wiring is provided as a circuit on the surface of the insulating layer 12 by etching the metal foil 13 on the surface of the metal-clad laminate 11 produced as described above to form wiring. For example, a method of manufacturing the printed circuit board 21 may be mentioned. That is, the wiring board 21 is obtained by partially removing the metal foil 13 on the surface of the metal-clad laminate 11 to form a circuit. In addition to the above-mentioned methods, methods for forming the circuit include, for example, semi-additive process (SAP) and modified semi-additive process (MSAP). The wiring board 21 is an insulating layer that has low dielectric properties (relative permittivity), excellent adhesion with metal foil and flame retardancy, high thermal conductivity, and suppresses deterioration of withstand voltage after heat treatment and moisture absorption treatment. It has 12.

Such wiring boards have low dielectric properties (relative permittivity), excellent adhesion to metal foil and flame retardancy, high thermal conductivity, and suppressed deterioration of withstand voltage after heat treatment and moisture absorption treatment. It is a wiring board including an insulating layer.

[Metal foil with resin]
FIG. 4 is a schematic cross-sectional view showing an example of a resin-coated metal foil 31 according to the present embodiment.

As shown in FIG. 4, the resin-coated metal foil 31 according to the present embodiment includes a resin layer 32 containing the resin composition or a semi-cured product of the resin composition, and a metal foil 13. This resin-coated metal foil 31 has a metal foil 13 on the surface of the resin layer 32. That is, this resin-coated metal foil 31 includes the resin layer 32 and the metal foil 13 laminated together with the resin layer 32. Further, the resin-coated metal foil 31 may include another layer between the resin layer 32 and the metal foil 13.

Further, the resin layer 32 may include a semi-cured product of the resin composition as described above, or may include an uncured resin composition. . That is, the resin-coated metal foil 31 may be a resin-coated metal foil that includes a resin layer containing a semi-cured product of the resin composition (the B-stage resin composition) and a metal foil, or The resin-coated metal foil may include a resin layer containing the previous resin composition (the A-stage resin composition) and a metal foil. Further, the resin layer only needs to contain the resin composition or a semi-cured product of the resin composition, and may or may not contain a fibrous base material. Further, the resin composition or the semi-cured product of the resin composition may be one obtained by drying or heating drying the resin composition. Further, as the fibrous base material, the same fibrous base material as the prepreg can be used.

Furthermore, as the metal foil, metal foils used for metal-clad laminates can be used without limitation. Examples of the metal foil include copper foil and aluminum foil.

The resin-coated metal foil 31 and the resin-coated film 41 described below may be provided with a cover fill or the like, if necessary. By providing a cover film, it is possible to prevent foreign matter from entering. The cover film is not particularly limited, but includes, for example, a polyolefin film, a polyester film, a polymethylpentene film, and a film formed by providing a release agent layer on these films.

The method for manufacturing the resin-coated metal foil 31 is not particularly limited as long as the resin-coated metal foil 31 can be manufactured. Examples of the method for manufacturing the resin-coated metal foil 31 include a method in which the varnish-like resin composition (resin varnish) is applied onto the metal foil 13 and heated. The varnish-like resin composition is applied onto the metal foil 13 using, for example, a bar coater. The applied resin composition is heated under conditions of, for example, 80° C. or higher and 180° C. or lower for 1 minute or more and 10 minutes or less. The heated resin composition is formed on the metal foil 13 as an uncured resin layer 32 . In addition, by the heating, the organic solvent can be volatilized from the resin varnish, and the organic solvent can be reduced or removed.

The resin-coated metal foil provided with the resin layer containing the resin composition or semi-cured product of this resin composition according to the present embodiment has low dielectric properties (relative dielectric constant), and has low adhesion with the metal foil and flame retardancy. This is a resin-coated metal foil that can suitably yield a cured product with excellent thermal conductivity and suppressed deterioration of withstand voltage after heat treatment and moisture absorption treatment.

[Film with resin]
FIG. 5 is a schematic cross-sectional view showing an example of the resin-coated film 41 according to the present embodiment.

As shown in FIG. 5, the resin-coated film 41 according to the present embodiment includes a resin layer 42 containing the resin composition or a semi-cured product of the resin composition, and a support film 43. This resin-coated film 41 includes the resin layer 42 and a support film 43 laminated together with the resin layer 42. Further, the resin-coated film 41 may include another layer between the resin layer 42 and the support film 43.

Further, the resin layer 42 may include a semi-cured product of the resin composition as described above, or may include an uncured resin composition. . That is, the resin-coated film 41 may include a resin layer containing a semi-cured product of the resin composition (the B-stage resin composition) and a support film, or may include a support film containing the resin composition before curing. The resin-coated film may include a resin layer containing a substance (the resin composition at A stage) and a support film. Further, the resin layer only needs to contain the resin composition or a semi-cured product of the resin composition, and may or may not contain a fibrous base material. Further, the resin composition or the semi-cured product of the resin composition may be one obtained by drying or heating drying the resin composition. Further, as the fibrous base material, the same fibrous base material as the prepreg can be used.

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

The resin-coated film 41 may include a cover film or the like, if necessary. By providing a cover film, it is possible to prevent foreign matter from entering. The cover film is not particularly limited, and examples thereof include polyolefin film, polyester film, and polymethylpentene film.

The support film and cover film may be subjected to surface treatments such as matte treatment, corona treatment, mold release treatment, and roughening treatment, as necessary.

The method for producing the resin-coated film 41 is not particularly limited as long as the resin-coated film 41 can be produced. Examples of the method for manufacturing the resin-coated film 41 include a method in which the varnish-like resin composition (resin varnish) is applied onto the support film 43 and heated. The varnish-like resin composition is applied onto the support film 43 using, for example, a bar coater. The applied resin composition is heated under conditions of, for example, 80° C. or higher and 180° C. or lower for 1 minute or more and 10 minutes or less. The heated resin composition is formed on the support film 43 as an uncured resin layer 42 . In addition, by the heating, the organic solvent can be volatilized from the resin varnish, and the organic solvent can be reduced or removed.

A resin-coated film including a resin layer containing the resin composition or a semi-cured product of this resin composition according to the present embodiment has low dielectric properties (relative dielectric constant), and has excellent adhesion to metal foil and flame retardancy. This is a resin-coated film that can suitably yield a cured product that has high thermal conductivity and suppresses deterioration of withstand voltage after heat treatment and moisture absorption treatment.

This specification discloses techniques in various aspects as described above, and the main techniques are summarized below.

The resin composition in the first aspect includes a radically polymerizable compound (A) having a carbon-carbon unsaturated double bond in the molecule, and a phosphoric acid ester compound (B) having an alicyclic hydrocarbon structure in the molecule. and an inorganic filler (C), and the cured product has a thermal conductivity of 1.0 W/m·K or more.

In the resin composition in the second embodiment, in the resin composition in the first embodiment, the phosphoric acid ester compound (B) has at least one structure represented by the following formula (1) in the molecule.

[In formula (1), R ₁ to R ₁₀ each independently 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. ]

In the resin composition according to the third aspect, in the resin composition according to the first or second aspect, the alicyclic hydrocarbon structure includes a 3- to 12-membered saturated alicyclic hydrocarbon structure.

The resin composition according to the fourth aspect is the resin composition according to any one of the first to third aspects, in which the phosphoric acid ester compound (B) has a structure represented by the following formula (2) in the molecule. Contains a phosphoric acid ester compound having at least one of the following.

[In formula (2), Ar ₁ and Ar ₂ each independently represent an arylene group, and T represents a divalent group of a 3- to 12-membered saturated alicyclic hydrocarbon. ]

In the resin composition according to any one of the first to fourth aspects, the content of the inorganic filler (C) is 100 parts by mass of the radically polymerizable compound (A). 100 to 380 parts by mass.

In the resin composition according to any one of the first to fifth aspects, the inorganic filler (C) is an inorganic filler having a thermal conductivity of 10 W/m·K or more. (C-1) and an inorganic filler (C-2) having a thermal conductivity of less than 10 W/m·K.

The resin composition according to the seventh aspect is the resin composition according to the sixth aspect, wherein the inorganic filler (C-1) is a boron nitride filler, an aluminum oxide filler, a magnesium oxide filler, a magnesium carbonate filler, a silicon nitride filler. , aluminum nitride filler.

The resin composition according to the eighth aspect is the resin composition according to the sixth or seventh aspect, wherein the inorganic filler (C-2) is selected from the group consisting of fused silica filler, magnesium hydroxide filler, and mica filler. Contains at least one species.

In the resin composition according to any one of the sixth to eighth aspects, the content of the inorganic filler (C-1) is higher than that of the inorganic filler (C-1). The amount is 25 to 70 parts by mass based on 100 parts by mass in total with the inorganic filler (C-2).

In the resin composition according to any one of the first to ninth aspects, the content of the phosphoric acid ester compound (B) is 100% by mass of the radically polymerizable compound (A). 15 to 50 parts by mass.

The resin composition in the eleventh aspect further includes an incompatible phosphorus compound (D) that is not compatible with the radically polymerizable compound (A) in the resin composition in any one of the first to tenth aspects. .

The resin composition according to the twelfth aspect is the resin composition according to any one of the first to eleventh aspects, wherein the incompatible phosphorus compound (D) is a phosphine oxide compound, a phosphinate compound, a polyphosphate compound, and at least one selected from the group consisting of phosphonium salt compounds.

In the resin composition according to any one of the first to twelfth aspects, the content of the phosphoric ester compound (B) is such that the content of the phosphoric ester compound (B) and the content of the phosphoric ester compound (B) are as follows. The amount is 25 to 100 parts by mass based on 100 parts by mass in total with the incompatible phosphorus compound (D).

The resin composition according to the fourteenth aspect is the resin composition according to any one of the first to thirteenth aspects, wherein the radically polymerizable compound (A) has a carbon-carbon unsaturated double bond in the molecule. Contains at least one selected from the group consisting of polyphenylene ether compounds, polyfunctional aromatic vinyl compounds, allyl compounds, polyfunctional methacrylate compounds, polyfunctional acrylate compounds, polybutadiene compounds, acenaphthylene compounds, and styrene compounds.

The resin composition according to the fifteenth aspect is the resin composition according to the fourteenth aspect, wherein the polyphenylene ether compound is at least one of a group represented by the following formula (3) and a group represented by the following formula (4). Contains polyphenylene ether compounds having in the molecule.

[In formula (3), p represents 0 to 10, Ar ₃ represents an arylene group, and R ₁₁ to R ₁₃ each independently represent a hydrogen atom or an alkyl group. ]

[In formula (4), R ₁₄ represents a hydrogen atom or an alkyl group. ]

The resin composition according to a sixteenth aspect is the resin composition according to any one of the first to fifteenth aspects, wherein a cured product of the resin composition has a dielectric constant of 3.2 to 3.8 at 10 GHz. be.

The prepreg in the seventeenth embodiment includes the resin composition in any one of the first to sixteenth embodiments or a semi-cured product of the resin composition, and a fibrous base material.

The resin-coated film in the eighteenth embodiment includes a resin layer containing the resin composition in any one of the first to sixteenth embodiments or a semi-cured product of the resin composition, and a support film.

The resin-coated metal foil in the nineteenth embodiment includes a resin layer containing the resin composition in any one of the first to sixteenth embodiments or a semi-cured product of the resin composition, and a metal foil.

The metal-clad laminate in the 20th embodiment includes an insulating layer containing the cured product of the resin composition in any one of the 1st to 16th embodiments or the cured prepreg in the 17th embodiment, and a metal foil. .

The wiring board in the 21st embodiment includes an insulating layer containing a cured product of the resin composition in any one of the 1st to 16th embodiments or a cured product of the prepreg in the 17th embodiment, and wiring.

The present invention will be explained in more detail below with reference to Examples, but the scope of the present invention is not limited thereto.

[Examples 1 to 17 and Comparative Examples 1 to 5]
In this example, each component used when preparing a resin composition will be explained.

((A) Radical polymerizable compound)
・PPE-1: Modified polyphenylene ether in which the terminal hydroxyl group of polyphenylene ether is modified with a methacryloyl group (SA9000 manufactured by SABIC Innovative Plastics, number average molecular weight Mn 2300, number of terminal functional groups: 2)
- PPE-2: A polyphenylene ether compound (modified polyphenylene ether compound obtained by reacting polyphenylene ether and chloromethylstyrene) having a vinylbenzyl group (ethenylbenzyl group) at the end. Specifically, it is a modified polyphenylene ether compound obtained by reacting as follows.

First, polyphenylene ether (SA90 manufactured by SABIC Innovative Plastics, number of terminal hydroxyl groups: 2, weight average molecular weight Mw 1700) was placed in a 1 liter three-necked flask equipped with a temperature controller, stirring device, cooling equipment, and dropping funnel. 200 g, 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.), and tetra-n-butylammonium as a phase transfer catalyst. 1.227 g of bromide and 400 g of toluene were charged and stirred. Then, the mixture was stirred until polyphenylene ether, chloromethylstyrene, and tetra-n-butylammonium bromide were dissolved in toluene. At that time, the mixture was gradually heated until the liquid temperature finally reached 75°C. Then, an aqueous sodium hydroxide solution (20 g of sodium hydroxide/20 g of water) was added dropwise to the solution as an alkali metal hydroxide over 20 minutes. Thereafter, the mixture was further stirred at 75°C for 4 hours. Next, after neutralizing the contents of the flask with 10% by mass hydrochloric acid, a large amount of methanol was added. By doing so, a precipitate formed in the liquid in the flask. That is, the product contained in the reaction solution in the flask was reprecipitated. Then, this precipitate was taken out by filtration, washed three times with a mixture of methanol and water in a mass ratio of 80:20, and then dried at 80° C. for 3 hours under reduced pressure.

The obtained solid was analyzed by ¹ H-NMR (400 MHz, CDCl ₃ , TMS). As a result of NMR measurement, a peak derived from 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 in the molecule at the end of the molecule. Specifically, it was confirmed that it was ethenylbenzylated polyphenylene ether. The obtained modified polyphenylene ether compound is represented by the above formula (13), Y in formula (13) is a dimethylmethylene group (represented by formula (11), and R ₄₃ and R ₄₄ in formula (11) was a methyl group), Ar ₃ was a phenylene group, R ₁₁ to R ₁₃ were hydrogen atoms, and p was 1.

Additionally, 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 is assumed to be X (mg). Then, this weighed modified polyphenylene ether was dissolved in 25 mL of methylene chloride, and a 10% by mass ethanol solution of tetraethylammonium hydroxide (TEAH) (TEAH:ethanol (volume ratio) = 15:85) was added to the solution. After adding 100 μL, absorbance (Abs) at 318 nm was measured using a UV spectrophotometer (UV-1600, manufactured by Shimadzu Corporation). Then, from the measurement results, the number of terminal hydroxyl groups of the modified polyphenylene ether was calculated using the following formula.

Residual OH amount (μmol/g) = [(25×Abs)/(ε×OPL×X)]×106
Here, ε indicates the extinction coefficient and is 4700 L/mol·cm. Further, OPL is the cell optical path length and is 1 cm.

Since the calculated residual OH amount (number of terminal hydroxyl groups) of the modified polyphenylene ether was almost zero, it was found that the hydroxyl groups of the polyphenylene ether before modification were almost modified. From this, it was found that the decrease from the number of terminal hydroxyl groups of polyphenylene ether before modification was the number of terminal hydroxyl groups of polyphenylene ether before modification. That is, it was found that the number of terminal hydroxyl groups of polyphenylene ether before modification is the number of terminal functional groups of modified polyphenylene ether. In other words, the number of terminal functional groups was two.

Additionally, the intrinsic viscosity (IV) of the modified polyphenylene ether was measured in methylene chloride at 25°C. Specifically, the intrinsic viscosity (IV) of the modified polyphenylene ether was determined by measuring a 0.18 g/45 ml methylene chloride solution (liquid temperature 25°C) of the modified polyphenylene ether using a viscometer (AVS500 Visco System manufactured by Schott). It was measured. As a result, the intrinsic viscosity (IV) of the modified polyphenylene ether was 0.086 dl/g.

Additionally, the molecular weight distribution of the modified polyphenylene ether was measured using GPC. Then, the weight average molecular weight (Mw) was calculated from the obtained molecular weight distribution. As a result, Mw was 1900.

・Curing agent-1: Triallyl isocyanurate (manufactured by Nippon Kasei Co., Ltd., "TAIC")
・Curing agent-2: Divinylbenzene (manufactured by Nippon Steel & Sumitomo Metal Corporation, "DVB810")

((B) Phosphoric ester compound)
・(B) Phosphoric ester compound-1: Phosphoric ester compound having an alicyclic hydrocarbon structure in the molecule (3,3,5-trimethyl-1,1-bis(4-hydroxyphenyl)cyclohexane and 2, It is a phosphoric acid ester compound obtained by reacting 6-xylenol and phosphoryl chloride. Specifically, it is a phosphoric acid ester compound obtained by reacting as follows.

<DXPC synthesis method>
First, dixylyl phosphorochloridate (DXPC) was synthesized. Specifically, it was synthesized as follows.

Into a 2-liter four-necked flask equipped with a stirrer, a thermometer, and a hydrochloric acid recovery device (condenser connected to a water scrubber), 767 g of phosphoryl chloride (phosphorus oxychloride) (manufactured by Tokyo Kasei Kogyo Co., Ltd.), 2, It was filled with 1200 g of 6-xylenol (manufactured by Tokyo Chemical Industry Co., Ltd.), 140 g of xylene as a solvent, and 6.2 g of magnesium chloride as a catalyst.

The liquid in the four-necked flask was heated while stirring, and the temperature of the liquid was gradually raised to 160° C. over about 3 hours. As a result, the reaction between 2,6-xylenol and phosphoryl chloride proceeded, and hydrogen chloride (hydrochloric acid gas) generated by the reaction was recovered with a water scrubber. Thereafter, the pressure inside the flask was gradually reduced to 20 kPa at the same temperature (160° C.) to remove xylene, unreacted phosphoryl chloride, unreacted 2,6-xylenol, and by-produced hydrogen chloride. By doing so, 1700 g of dixylyl phosphorochloridate (DXPC) represented by the following formula (27) was obtained.

<Synthesis method of phosphate ester compound>
Next, using dixylyl phosphorochloridate (DXPC) obtained by the above-mentioned DXPC synthesis method, a phosphoric acid ester compound having an alicyclic hydrocarbon structure in the molecule (represented by the above formula (22) A phosphoric acid ester compound) was synthesized. Specifically, it was synthesized as follows.

In a 2-liter four-necked flask equipped with a stirrer, thermometer, dropping funnel, and condenser, 460 g of dixylylphosphorochloridate (DXPC) obtained by the DXPC synthesis method, 3,3,5- 196 g of trimethyl-1,1-bis(4-hydroxyphenyl)cyclohexane (BisP-TMC manufactured by Honshu Kagaku Kogyo Co., Ltd.), 540 g of toluene as a solvent, and 140 g of tetrahydrofuran were charged. Additionally, 151 g of triethylamine was charged into the dropping funnel as a hydrogen halide scavenger.

The liquid in the four-necked flask was heated while stirring until the liquid temperature reached 65°C. Thereafter, while maintaining the same temperature (65° C.), triethylamine in the dropping funnel was added dropwise over 1 hour and 30 minutes. After the dropwise addition was completed, the mixture was stirred at the same temperature (65°C) for 2 hours. The reaction product thus obtained was washed with dilute hydrochloric acid and water, neutralized and washed with an aqueous sodium hydroxide solution, and washed again with water. Thereafter, the solution was heated until the temperature reached 110° C., the pressure was reduced to 1 kPa, and water, toluene, and tetrahydrofuran were recovered. Furthermore, steam distillation was performed at 110° C. under a reduced pressure of 1 kPa to distill off low-boiling components, and then the mixture was cooled to room temperature. By doing so, 553 g of a pale yellow transparent glassy solid was obtained. It was confirmed by ¹ H-NMR that the obtained product was a phosphoric acid ester compound represented by the above formula (22).

(Other phosphate ester compounds)
・Other phosphate ester compounds-1: Phosphate ester compounds that do not have an alicyclic hydrocarbon structure in the molecule (manufactured by Daihachi Chemical Co., Ltd., "PX-200", represented by the following formula (28) phosphoric acid ester compound)

((D) Incompatible phosphorus compound)
・(D) Incompatible phosphorus compound-1: diphenylphosphine oxide compound (manufactured by Shinichi Kako Co., Ltd., "PQ60")
・(D) Incompatible phosphorus compound-2: phosphinate compound (manufactured by Clariant Japan Co., Ltd., "OP-935")

((C) Inorganic filler)
・(C-1) Inorganic filler-1: Boron nitride filler (manufactured by Denka Co., Ltd., "SGP", thermal conductivity 40 to 80 W/m K, volume average particle diameter 18 μm)
・(C-1) Inorganic filler-2: Boron nitride filler (manufactured by MARUKA Co., Ltd., "AP-20S", thermal conductivity 60 W/m K, volume average particle diameter 0.7 μm)
・(C-1) Inorganic filler-3: Aluminum oxide filler (manufactured by Denka Co., Ltd., "DAW-03DC", thermal conductivity 20 to 40 W/m K, volume average particle diameter 4.9 μm)
・(C-1) Inorganic filler-4: Magnesium carbonate filler (manufactured by Kamishima Chemical Co., Ltd., "Magthermo MS-L", thermal conductivity 15 W/m K, volume average particle diameter 8.0 μm)
・(C-1) Inorganic filler-5: Magnesium oxide filler (manufactured by Ube Materials Co., Ltd., "RF-10CS", thermal conductivity 60 W/m K, volume average particle diameter 6.0 μm)
・(C-2) Inorganic filler-1: Silica filler (manufactured by Denka Co., Ltd., "FB-7SDC", thermal conductivity 1 W/m K, volume average particle diameter 5 μm)

(Reaction initiator)
・Reaction initiator-1: peroxide (1,3-bis(butylperoxyisopropyl)benzene, manufactured by NOF Corporation, "Perbutyl P")

(coupling agent)
・Coupling agent-1: Silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., "KBM-503")

(free radical compound)
・Free radical compound-1: 4-benzoyloxy TEMPO, a free radical compound represented by the following formula (manufactured by Tokyo Chemical Industry Co., Ltd., "H0878")

[Preparation method]
First, each organic resin component other than the inorganic filler is added to toluene as a solvent and mixed in the composition (parts by mass) shown in Tables 1 and 2 so that the solid content concentration is 60 to 70% by mass. Ta. The mixture was stirred for 60 minutes. Thereafter, each component was added to the resulting liquid in the proportions (parts by mass) listed in Tables 1 and 2, and the inorganic filler was dispersed using a bead mill. By doing so, a varnish-like resin composition (varnish) was obtained.

Next, an evaluation board (cured prepreg) was obtained as follows.

A prepreg was produced by impregnating a fibrous base material (glass cloth: #1078 type, L glass manufactured by Asahi Kasei Corporation) with the obtained varnish, and then heating and drying it at 120° C. for 2 minutes. Then, 1, 2, 4, and 6 sheets of each of the obtained prepregs were stacked, and each side was laminated with copper foil (Fukuda Metal Foil & Powder Industries Co., Ltd. "CF-T4X-SV" copper foil thickness: 35 μm) and heated. Copper-clad laminates of four different thicknesses were prepared by heating to a temperature of 200°C at a rate of 4°C/min and heating and pressing at 200°C for 120 minutes at a pressure of 3 MPa.

The copper-clad laminate prepared as described above was used as an evaluation board and evaluated by the method shown below. In addition, in the evaluation test of dielectric properties (relative permittivity) described later, a copper-clad laminate made of four prepregs from which the copper foil was removed (cured prepreg) was used. In the copper foil peel strength evaluation test described below, a copper-clad laminate made of four prepreg layers was used. In the measurement of thermal conductivity described below, a cured product of one prepreg and a copper-clad laminate made of two prepregs from which the copper foil was removed (cured prepreg) were used. In the flame retardancy evaluation test described below, a copper-clad laminate made of six prepregs from which the copper foil was removed (cured prepreg) was used.

In addition, in the evaluation test of withstand voltage after heat treatment and moisture absorption treatment, which will be described later, an evaluation substrate (cured prepreg) was obtained as follows. A prepreg was produced by impregnating a fibrous base material (glass cloth: #3313 type, E glass, manufactured by Nitto Boseki Co., Ltd.) with the obtained varnish, and then heating and drying it at 110° C. for 2 minutes. Four sheets of each of the obtained prepregs were stacked, and copper foil (Fukuda Metal Foil & Powder Industries Co., Ltd. "CF-T4X-SV" copper foil thickness: 35 μm) was laminated on both sides, and the temperature was increased at a heating rate of 4°C/min. Copper-clad laminates of three different thicknesses were produced by heating to 200° C. and heating and pressing at 200° C. for 120 minutes at a pressure of 3 MPa. The obtained copper-clad laminate from which the copper foil was removed (cured prepreg) was used.

[Dielectric properties (relative permittivity)]
The relative dielectric constant (Dk) of the evaluation substrate (cured prepreg) at a frequency of 10 GHz was measured using the cavity resonator perturbation method. Specifically, the dielectric constant of the evaluation board at 10 GHz was measured using a network analyzer (N5230A manufactured by Keysight Technologies, Inc.). Note that a dielectric constant of 3.2 to 3.8 is favorable.

[Copper foil peel strength]
Using the evaluation board described above, the peel strength of the copper foil from the insulating layer was measured in accordance with JIS C 6481. A pattern with a width of 10 mm and a length of 100 mm was formed and peeled off at a speed of 50 mm/min using a tensile tester, and the peel strength at that time was measured. The unit of measurement is N/mm. The acceptance criterion in this example was 0.50 N/mm or more.

[Thermal conductivity]
The thermal conductivity of the obtained evaluation board (cured prepreg) was measured by a method based on ASTM D5470. Specifically, using a thermal property evaluation device (T3Ster DynTIM Tester manufactured by Mentor Graphics), the thermal resistance and The thickness was measured, the measured values were plotted on a graph, approximated by a straight line, and the thermal conductivity was calculated from the increase in thermal resistance and thickness. The acceptance criterion for thermal conductivity in this example was 1.0 W/m·K or more.

[Flame retardance]
A test piece with a length of 125 mm and a width of 12.5 mm was cut out from the evaluation board. Then, a combustion test was conducted on this test piece according to "Test for Flammability of Plastic Materials-UL 94" by Underwriters Laboratories. As a result, if the flammability was at the "V-0" level, it was evaluated as "V-0", and if it was at the "HB" level, it was evaluated as "HB".

[Withstand voltage after heat treatment and moisture absorption treatment]
A test piece with a diameter of 100±5 mm and a thickness of 0.5 mm was cut from the evaluation board. Then, with respect to this test piece, the withstand voltage after heat treatment and moisture absorption treatment was measured using a withstand voltage (AC) testing device (YOU-DAA-100R manufactured by Onda Co., Ltd.) according to the ASTM-D-149 standard test method. did. The specific measurement conditions are as follows.

(Selection of boost speed)
A test piece with a diameter of 100±5 mm and a thickness of 0.5 mm was cut from the evaluation board. This test piece was sandwiched between upper and lower electrodes (shape: cylindrical, material: stainless steel) with a diameter of 25 mm x 25 mm and an edge of 3.2 mm R, and a voltage increase rate at which dielectric breakdown occurred from 0 V in 10 to 20 seconds was selected.

(Aging treatment)
Three test pieces each having a diameter of 100±5 mm and a thickness of 0.5 mm were further cut out from the evaluation board. The cut test pieces were subjected to aging treatment at a treatment temperature of 150° C. and treatment times of 500 hours, 750 hours, and 1000 hours, respectively. Then, the test pieces subjected to each aging treatment were subjected to a moisture absorption treatment at 35° C. and 90% for 96 hours.

(Measurement of withstand voltage)
In the test piece subjected to aging and moisture absorption treatment, the voltage was increased at the voltage increase rate selected above, and the dielectric breakdown voltage was measured. A significant difference was determined by the aging treatment time (half-life time) at which the withstand voltage of the test piece after the aging treatment was less than 50% when the withstand voltage of the test piece that had not been subjected to the aging treatment was 100%. The evaluation criteria are as follows.
◎: Withstand voltage 50% or more after aging treatment time of 1000 hours 〇: Withstand voltage 50% or more after aging treatment time 750 hours, withstand voltage less than 50% after aging treatment time 1000 hours △: Withstand voltage 50% after aging treatment time 500 hours Above, withstand voltage is less than 50% after aging treatment time of 750 hours ×: Withstand voltage is less than 50% after aging treatment time of 500 hours

[Consideration]
As can be seen from Table 1, all examples using the resin composition of the present invention had low dielectric properties (relative permittivity), excellent adhesion to metal foil and flame retardancy, and high thermal conductivity. It was confirmed that a cured product was obtained in which the voltage resistance was high and the deterioration of withstand voltage after heat treatment and moisture absorption treatment was suppressed.

On the other hand, as shown in Table 2, the samples of Comparative Examples 1 to 3 and 5, which did not contain the phosphoric acid ester compound (B) having an alicyclic hydrocarbon structure in the molecule, had good peel strength, flame retardancy, Or, the suppression of deterioration of withstand voltage after heat treatment and moisture absorption treatment was insufficient. Specifically, the sample of Comparative Example 1 using only an incompatible phosphorus compound was unable to obtain sufficient peel strength. In addition, a sample of Comparative Example 2 using only a phosphoric acid ester compound that does not have an alicyclic hydrocarbon structure in its molecule, and a phosphoric ester compound that does not have an alicyclic hydrocarbon structure in its molecule In the sample of Comparative Example 3 using a phosphorus compound incompatible with the above, deterioration in withstand voltage was observed after heat treatment and moisture absorption treatment. The sample of Comparative Example 5 in which no flame retardant was used did not have sufficient flame retardancy. Further, the sample of Comparative Example 4 had a thermal conductivity of a cured product of the resin composition of less than 1.0 W/m·K, and thus did not have sufficient thermal conductivity.

Furthermore, when comparing Example 1 and Example 2, the sample of Example 2 using divinylbenzene as a curing agent was more heat-treated and moisture-absorbing than the sample of Example 1 using triallylisocyanurate as a curing agent. It was confirmed that the subsequent deterioration of withstand voltage was suppressed.

Moreover, when comparing Example 1 and Example 3, the sample of Example 3 using a modified polyphenylene ether compound having a vinylbenzyl group at the end is different from the sample using a polyphenylene ether compound in which the terminal hydroxyl group of polyphenylene ether is modified with a methacroyl group. It was confirmed that the sample had a lower dielectric property superior to that of the sample of Example 1 used.

In addition, the samples of Examples 7, 16, and 17 had a lower content of inorganic filler (C-2) than Example 1, and together with boron nitride filler as inorganic filler (C-1), aluminum oxide filler, Magnesium carbonate filler and magnesium oxide filler are used respectively. It was confirmed that the samples of Examples 7, 16, and 17 had better thermal conductivity than the sample of Example 1. This is because the thermal conductivity of the inorganic filler itself is higher for the inorganic filler (C-1) than for the inorganic filler (C-2), so the thermal conductivity of the cured product also tends to be higher. It is thought that.

This application is based on Japanese Patent Application No. 2022-148396 filed on September 16, 2022, and its contents are included in the present application.

In order to express the present invention, the present invention has been appropriately and fully explained through the embodiments above with reference to specific examples, drawings, etc., but those skilled in the art will be able to modify and/or improve the above-described embodiments. It should be recognized that this can be done easily. Therefore, unless the modification or improvement carried out by a person skilled in the art does not leave the scope of the claims stated in the claims, such modifications or improvements do not fall outside the scope of the claims. It is interpreted as encompassing.

The present invention has wide industrial applicability in technical fields related to electronic materials and various devices using the same.

Claims

A radically polymerizable compound (A) having a carbon-carbon unsaturated double bond in the molecule,
A phosphoric acid ester compound (B) having an alicyclic hydrocarbon structure in the molecule;
Including an inorganic filler (C),
A resin composition whose cured product has a thermal conductivity of 1.0 W/m·K or more.
The resin composition according to claim 1, wherein the phosphoric acid ester compound (B) has at least one structure represented by the following formula (1) in the molecule.

[In formula (1), R 1 to R 10 each independently 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. ]
The resin composition according to claim 1, wherein the alicyclic hydrocarbon structure includes a 3- to 12-membered saturated alicyclic hydrocarbon structure.
The resin composition according to claim 1, wherein the phosphoric ester compound (B) contains a phosphoric ester compound having at least one structure represented by the following formula (2) in the molecule.

[In formula (2), Ar 1 and Ar 2 each independently represent an arylene group, and T represents a divalent group of a 3- to 12-membered saturated alicyclic hydrocarbon. ]
The resin composition according to claim 1, wherein the content of the inorganic filler (C) is 100 to 380 parts by mass based on 100 parts by mass of the radically polymerizable compound (A).
The inorganic filler (C) is an inorganic filler (C-1) with a thermal conductivity of 10 W/m・K or more, and an inorganic filler (C-2) with a thermal conductivity of less than 10 W/m・K. The resin composition according to claim 1, comprising:
7. The inorganic filler (C-1) includes at least one selected from the group consisting of boron nitride filler, aluminum oxide filler, magnesium oxide filler, magnesium carbonate filler, silicon nitride filler, and aluminum nitride filler. The resin composition described.
The resin composition according to claim 6, wherein the inorganic filler (C-2) contains at least one selected from the group consisting of fused silica filler, magnesium hydroxide filler, and mica filler.
A content of the inorganic filler (C-1) is 25 to 70 parts by mass based on a total of 100 parts by mass of the inorganic filler (C-1) and the inorganic filler (C-2). 6. The resin composition according to 6.
The resin composition according to claim 1, wherein the content of the phosphoric acid ester compound (B) is 15 to 50 parts by mass based on 100 parts by mass of the radically polymerizable compound (A).
The resin composition according to claim 1, further comprising an incompatible phosphorus compound (D) that is incompatible with the radically polymerizable compound (A).
The resin composition according to claim 11, wherein the incompatible phosphorus compound (D) contains at least one selected from the group consisting of a phosphine oxide compound, a phosphinate compound, a polyphosphate compound, and a phosphonium salt compound.
A content of the phosphoric acid ester compound (B) is 25 to 100 parts by mass based on a total of 100 parts by mass of the phosphoric acid ester compound (B) and the incompatible phosphorus compound (D). 12. The resin composition according to 11.
The radically polymerizable compound (A) is a polyphenylene ether compound having a carbon-carbon unsaturated double bond in the molecule, a polyfunctional aromatic vinyl compound, an allyl compound, a polyfunctional methacrylate compound, a polyfunctional acrylate compound, a polybutadiene compound, The resin composition according to claim 1, containing at least one selected from the group consisting of an acenaphthylene compound and a styrene compound.
The resin composition according to claim 14, wherein the polyphenylene ether compound contains a polyphenylene ether compound having at least one of a group represented by the following formula (3) and a group represented by the following formula (4) in the molecule.

[In formula (3), p represents 0 to 10, Ar 3 represents an arylene group, and R 11 to R 13 each independently represent a hydrogen atom or an alkyl group. ]

[In formula (4), R 14 represents a hydrogen atom or an alkyl group. ]
The resin composition according to claim 1, wherein the cured product of the resin composition has a dielectric constant of 3.2 to 3.8 at 10 GHz.
A prepreg comprising the resin composition according to any one of claims 1 to 16 or a semi-cured product of the resin composition, and a fibrous base material.
A resin-coated film comprising a resin layer containing the resin composition according to any one of claims 1 to 16 or a semi-cured product of the resin composition, and a support film.
A resin-coated metal foil comprising a resin layer containing the resin composition according to any one of claims 1 to 16 or a semi-cured product of the resin composition, and a metal foil.
A metal-clad laminate comprising an insulating layer containing a cured product of the resin composition according to any one of claims 1 to 16, and metal foil.
A wiring board comprising an insulating layer containing a cured product of the resin composition according to any one of claims 1 to 16, and wiring.
A metal-clad laminate comprising an insulating layer containing the cured prepreg according to claim 17 and metal foil.
A wiring board comprising an insulating layer containing the cured prepreg according to claim 17 and wiring.