Resin composition, cured product in which resin composition is used, prepreg, printed wiring board, and electronic component for high frequencies

Abstract

Provided is a resin composition exhibiting excellent high frequency characteristics and heat resistance reliability. The resin composition comprises: (A) a polyphenylene ether resin that has, at a terminal end, a functional group including a carbon-carbon double bond; and (B) a compound that is a liquid at 25°C and has an isocyanuric ring structure and two allyl groups per molecule. (Provided that R1 in formula (1) is a hydrogen atom or an alkyl group.)

Description

Resin composition, and cured product, prepreg, printed wiring board, and high frequency electronic component using the same

[0001] The present invention relates to a resin composition, and to a cured product, a prepreg, a printed wiring board, and a high-frequency electronic component using the same.

[0002] In recent years, communication speeds have been increasing for communication electronic devices (electronic substrates) such as smartphones and tablet devices and communication base stations, and the construction of 5G communication networks is progressing. To reduce the loss of electrical signals in the substrates used in communication electronic devices, the demand for low dielectric materials and highly integrated multilayer substrates has increased significantly. To achieve this, low-dielectric resin substrates, ceramic substrates, low-dielectric interlayer adhesives, and the like are being used.

[0003] It is known that thermosetting polyphenylene ether is used as a material for adhesive layers, coverlays, substrates, etc. of multilayer printed wiring boards for high frequency applications (see, for example, Patent Document 1). From the viewpoints of reactivity and solubility in solvents, it is considered preferable that the thermosetting polyphenylene ether has a low molecular weight, and that a vinyl compound (a functional group having a vinyl group) is preferred.

[0004] International Publication No. 2008 / 018483

[0005] However, the present inventors have found that a cured polyphenylene ether obtained by reacting a thermosetting polyphenylene ether having a vinyl group as a functional group suffers from a problem that it undergoes extremely rapid oxidative degradation at high temperatures, resulting in large fluctuations in the value of the dielectric loss tangent (tan δ) in terms of heat resistance reliability.

[0006] The present invention has been made in consideration of the problems of the prior art. The present invention provides a resin composition having excellent heat resistance reliability (in other words, a small rate of change in dielectric loss tangent (tan δ)). Furthermore, the present invention provides a cured product, a prepreg, a printed wiring board, and a high-frequency electronic component using such a resin composition.

[0007] According to the present invention, there are provided the following resin compositions, cured products, prepregs, printed wiring boards, and high-frequency electronic components.

[0008] [1] A resin composition comprising: (A) a polyphenylene ether resin having a group represented by the following formula (1) at its terminal; and (B) a compound having an isocyanuric ring structure and two allyl groups in one molecule, and being liquid at 25°C.

[0009] (However, in the formula (1), R １ represents a hydrogen atom or an alkyl group.

[0010] [2] The resin composition according to [1], wherein the component (B) is a compound represented by the following formula (2):

[0011] (However, in the above formula (2), R ２ is an alkyl group having 4 to 14 carbon atoms.

[0012] [3] The resin composition according to [1] or [2], further comprising (C) a thermoplastic resin having a number average molecular weight of 30,000 or more.

[0013] [4] The resin composition according to [3], wherein the component (C) is a thermoplastic elastomer having a dielectric loss tangent (tan δ) of less than 0.005 in a frequency range of 1 to 100 GHz.

[0014] [5] The resin composition according to [3] or [4], wherein the (C) component is contained in an amount of 20 to 80 parts by mass per 100 parts by mass of the total of the resin components.

[0015] [6] The resin composition according to any one of [1] to [5] above, further comprising (D) an inorganic filler.

[0016] [7] The resin composition according to [6], wherein the (D) component is contained in an amount of 50% by mass or more based on 100% by mass of nonvolatile components in the resin composition.

[0017] [8] The resin composition according to [7], wherein the (D) component is contained in an amount of 60 to 90% by mass based on 100% by mass of nonvolatile components in the resin composition.

[0018] [9] The resin composition according to any one of [1] to [8] above, further comprising (E) a curing catalyst.

[0019]

[10] The resin composition according to any one of [1] to [9], comprising 10 to 50 parts by mass of the component (A) per 100 parts by mass of the total of the resin components.

[0020]

[11] The resin composition according to any one of [1] to

[10] , comprising 3 to 40 parts by mass of the (B) component per 100 parts by mass of the total of the resin components.

[0021]

[12] A cured product of the resin composition according to any one of [1] to

[11] .

[0022]

[13] A prepreg using the resin composition according to any one of [1] to

[11] .

[0023]

[14] A printed wiring board having a cured layer made of the resin composition according to any one of [1] to

[11] .

[0024]

[15] A high-frequency electronic component having the cured product according to

[12] .

[0025] The resin composition of the present invention exhibits the effect of excellent heat resistance reliability (in other words, a small rate of change in dielectric loss tangent (tan δ)). Furthermore, the resin composition of the present invention has good fluidity, so that it is easily embedded in a substrate, and also has excellent film-forming properties. Therefore, the resin composition of the present invention can be suitably used for cured products, prepregs, printed wiring boards, high-frequency electronic components, and the like.

[0026] Furthermore, the cured product, prepreg, printed wiring board, and high-frequency electronic component of the present invention use the resin composition of the present invention described above, and exhibit the effects of excellent dielectric properties, heat resistance, and embeddability.

[0027] 1A and 1B are plan views showing patterning in an evaluation of board pattern embeddability, and are photographic examples of cases where embeddability is good and poor in an evaluation of board pattern embeddability, respectively.

[0028] While the present invention will be described below with reference to exemplary embodiments, it should be understood that the present invention is not limited to the following exemplary embodiments. Therefore, it should be understood that modifications and improvements to the following exemplary embodiments, based on the ordinary knowledge of those skilled in the art, are also within the scope of the present invention, provided that they do not deviate from the spirit of the present invention.

[0029] [Resin Composition] One embodiment of the resin composition of the present invention is a resin composition comprising: (A) a polyphenylene ether resin having a group represented by the following formula (1) at its terminal; and (B) a compound having an isocyanuric ring structure and two allyl groups in one molecule and being liquid at 25°C. Hereinafter, (A) the polyphenylene ether resin having a group represented by the following formula (1) at its terminal may be referred to as component (A). Similarly, (B) the compound having an isocyanuric ring structure and two allyl groups in one molecule and being liquid at 25°C may be referred to as component (B).

[0030] (However, in the above formula (1), R １ represents a hydrogen atom or an alkyl group.

[0031] The resin composition of this embodiment has excellent high-frequency characteristics, heat resistance, and heat resistance reliability. Excellent heat resistance reliability refers to a small change in dielectric loss tangent (tan δ) in a heat resistance reliability test. For example, an example of excellent heat resistance reliability is a small rate of change in dielectric loss tangent (tan δ) after being left in an environment of 125°C for 1,000 hours compared to before being left. Furthermore, the resin composition of this embodiment has good fluidity, so it also has good embeddability in a substrate.

[0032] The polyphenylene ether resin used as component (A) has a group represented by the above formula (1) at its terminal, which can improve the heat resistance and heat resistance reliability described above. The present inventors have successfully developed a resin composition having excellent dielectric properties and heat resistance, which can be used in adhesive layers, coverlays, substrates, etc. of multilayer printed wiring boards for high-frequency applications (e.g., Japanese Patent Application No. 2021-149098). This resin composition comprises (A) a polyphenylene ether resin having a functional group containing a carbon-carbon double bond at its terminal, and (B) a compound having an isocyanuric ring structure and two allyl groups in one molecule and being liquid at 25°C. As a result of further intensive research into such resin compositions, the present inventors discovered that by converting the terminal of the polyphenylene ether resin used as component (A) to a group represented by the above formula (1), the heat resistance and heat resistance reliability of the resin composition are significantly improved, leading to the completion of the present invention.

[0033] As described above, the compound serving as component (B) is a compound having an isocyanuric ring structure and two allyl groups in one molecule, which can reduce the melt viscosity of the resin composition and improve its embeddability in wiring. Furthermore, the compound serving as component (B) has two allyl groups, which allows it to obtain extremely good low dielectric properties. Furthermore, the resin composition of this embodiment can obtain high heat resistance and heat resistance reliability by crosslinking and curing such components (A) and (B).

[0034] In addition to the components (A) and (B), the resin composition of the present embodiment may contain other components such as a thermoplastic resin (C), an inorganic filler (D), and a curing catalyst (E). Hereinafter, the components described above may be referred to as components (C) to (E) as appropriate.

[0035] [Component (A)] Component (A) is a polyphenylene ether resin having a group represented by the above formula (1) at its terminal. Component (A) is not particularly limited as long as it has a group represented by the above formula (1) at its terminal and a polyphenylene ether in its skeleton. By including component (A), heat resistance and heat resistance reliability can be extremely effectively improved. Hereinafter, a polyphenylene ether resin having a group represented by the above formula (1) as component (A) may be referred to as a modified polyphenylene ether. The modified polyphenylene ether of component (A) is preferably a thermosetting resin.

[0036] In the above formula (1), R １ represents a hydrogen atom or an alkyl group. １ The alkyl group is preferably an alkyl group having 1 to 3 carbon atoms, more preferably an alkyl group having 1 carbon atom. Specific examples include a methyl group, an ethyl group, and a propyl group.

[0037] Examples of the group represented by formula (1) include an acrylate group and a methacrylate group.

[0038] Furthermore, the modified polyphenylene ether having a group represented by formula (1) has a polyphenylene ether chain in the molecule, and preferably has, for example, a repeating unit represented by the following structural formula (3) in the molecule.

[0039]

[0040] In the structural formula (3), m represents 1 to 50. ２２ ~R ２５ are each independently and may be the same as or different from one another. ２２ ~R ２５ represents a hydrogen atom or an alkyl group.

[0041] R ２２ ~R ２５ The alkyl group in is not particularly limited, but is preferably an alkyl group having 1 to 8 carbon atoms, and more preferably an alkyl group having 1 to 3 carbon atoms. Specific examples include a methyl group, an ethyl group, a propyl group, a hexyl group, and an octyl group.

[0042] Examples of modified polyphenylene ethers having a group represented by formula (1) include those having a group represented by formula (1) at the terminal of a polyphenylene ether represented by formula (4) or (5) below. Specific examples of modified polyphenylene ethers include modified polyphenylene ethers represented by formula (6) or (7) below.

[0043]

[0044] In formulas (4) to (7), s and t are preferably such that the sum of s and t is, for example, 1 to 30. Furthermore, s is preferably 0 to 20, and t is preferably 0 to 20. That is, it is preferable that s represents 0 to 20, t represents 0 to 20, and the sum of s and t represents 1 to 30. Furthermore, in formulas (4) to (7), Y represents an alkylene group having 1 to 3 carbon atoms or a direct bond, and examples of this alkylene group include a dimethylmethylene group. Furthermore, in formulas (6) and (7), R １ is R in the above formula (1). １ and represents a hydrogen atom or an alkyl group. The alkyl group is not particularly limited, and is preferably, for example, an alkyl group having 1 to 3 carbon atoms, and more preferably an alkyl group having 1 carbon atom. Specific examples include a methyl group, an ethyl group, and a propyl group.

[0045] The number-average molecular weight (Mn) of the modified polyphenylene ether having a group represented by formula (1) is not particularly limited. Specifically, it is preferably 500 to 5,000, more preferably 800 to 4,000, and even more preferably 1,000 to 3,000. Here, the number-average molecular weight may be measured by a general molecular weight measurement method, and specifically, a value measured using gel permeation chromatography (GPC) may be mentioned. Furthermore, when the modified polyphenylene ether having a group represented by formula (1) has a repeating unit represented by formula (3) in the molecule, m is preferably a value such that the weight-average molecular weight of the modified polyphenylene ether falls within this range. Specifically, m is preferably 1 to 50.

[0046] When the number-average molecular weight of the modified polyphenylene ether having the group represented by formula (1) is within the above-mentioned range, it has excellent dielectric properties derived from the polyphenylene ether and also has excellent embeddability in a substrate. For example, when the number-average molecular weight of a conventional polyphenylene ether is within the above-mentioned range, it has a relatively low molecular weight and tends to have excellent embeddability in a substrate. On the other hand, since the modified polyphenylene ether having the group represented by formula (1) has the group represented by formula (1) at its terminal, it can improve the heat resistance and heat resistance reliability of the cured product.

[0047] Furthermore, in the modified polyphenylene ether used as component (A), the average number of groups represented by the above formula (1) at the molecular terminals per molecule of the modified polyphenylene ether (number of terminal functional groups) is not particularly limited. Specifically, it is preferably 1 to 5, more preferably 1 to 3, and even more preferably 1.5 to 3. If the number of terminal functional groups is too small, curability tends to be poor, and it is difficult to obtain sufficient strength, adhesiveness, and heat resistance of the cured product. Furthermore, if the number of terminal functional groups is too large, the reactivity may be too high, which may result in problems such as reduced shelf life of the resin composition, reduced fluidity of the resin composition, brittleness of the cured product, and reduced adhesiveness. In other words, the use of such modified polyphenylene ether may result in problems such as molding defects such as the generation of voids during multilayer molding, increased susceptibility to cracking and delamination of the substrate, and difficulty in obtaining highly reliable printed wiring boards.

[0048] The number of terminal functional groups in the modified polyphenylene ether described above can be, for example, a numerical value representing the average number of groups represented by the above formula (1) per molecule of all modified polyphenylene ethers present in 1 mole of the modified polyphenylene ether. This number of terminal functional groups can be measured, for example, by measuring the number of hydroxyl groups remaining in the obtained modified polyphenylene ether and calculating the difference from the number of hydroxyl groups in the polyphenylene ether before modification. This difference from the number of hydroxyl groups in the polyphenylene ether before modification is the number of terminal functional groups. The number of hydroxyl groups remaining in the modified polyphenylene ether can be measured by adding a quaternary ammonium salt (tetraethylammonium hydroxide) that associates with hydroxyl groups to a solution of the modified polyphenylene ether and measuring the UV absorbance of the resulting mixed solution.

[0049] The method for synthesizing the modified polyphenylene ether used as component (A) is not particularly limited as long as it is possible to synthesize a modified polyphenylene ether having a group represented by the above formula (1) at its terminal.

[0050] The component (A) may be a modified polyphenylene ether having a group represented by the above formula (1) at its terminal, which may be used alone, or two or more modified polyphenylene ethers having a group represented by the above formula (1) at their terminal may be used in combination.

[0051] There are no particular restrictions on the content of component (A) in the resin composition, but it is preferable that the content of component (A) be 10 to 50 parts by mass, more preferably 20 to 45 parts by mass, and particularly preferably 25 to 40 parts by mass, per 100 parts by mass of the total resin components. When the content of component (A) within this range per 100 parts by mass of the total resin components is within this range, the curability is good, and the flexibility of the resin composition, the heat resistance of the cured product, and processability such as film formation are improved. The toughness of the cured product is not lost, and adhesive properties are not reduced. The content of component (A) in the resin components can be measured, for example, by infrared spectroscopy (FTIR) or gas chromatography mass spectrometry. Examples of resin components in the resin composition include component (A), component (B), and, optionally, component (C). Therefore, the content of component (A) per 100 parts by mass of the total resin components in the resin composition can be determined, for example, as the content of component (A) per 100 parts by mass of the total of components (A), (B), and (C). Note that the content of component (B) per 100 parts by mass of the total resin components, which will be described later, can also be calculated in the same manner as above.

[0052] An example of the modified polyphenylene ether having a group represented by the above formula (1) at its terminal, component (A), is "Noryl SA9000" manufactured by SABIC Innovative Plastics.

[0053] [Component (B)] Component (B) is a compound that has an isocyanuric ring structure and two allyl groups per molecule and is liquid at 25°C. The inclusion of component (B) reduces the melt viscosity of the resin composition, improving its embeddability in wiring. Furthermore, the compound as component (B) has two allyl groups, resulting in extremely good low dielectric properties. For example, using a compound having an isocyanuric ring structure and three allyl groups per molecule instead of component (B) would not provide sufficient low dielectric properties. It is believed that using a compound having three allyl groups results in a three-dimensional crosslinked structure, resulting in insufficient dielectric properties. On the other hand, a compound having a bifunctional allyl group, such as component (B) of the resin composition of this embodiment, results in a linear crosslinked structure, resulting in a smaller dipole moment, a measure of molecular polarization, and therefore low dielectric properties. It is believed that the isocyanuric ring structure in component (B) improves the heat resistance and heat resistance reliability of the resin composition. In addition, embeddability is improved when the component (B) of the resin composition of this embodiment is a compound that is liquid at 25° C. On the other hand, if a compound that is solid at 25° C. is used as the component (B), embeddability will be deteriorated, which is not preferable.

[0054] The molecular weight of component (B) is preferably 300 to 400, and more preferably 320 to 400. When the molecular weight of component (B) is within the above range, the dielectric properties and fluidity are excellent.

[0055] The component (B) is preferably a compound represented by the following formula (2).

[0056]

[0057] In the above formula (2), R ２ is an alkyl group having 4 to 14 carbon atoms, preferably an alkyl group having 8 to 14 carbon atoms, and particularly preferably an alkyl group having 10 to 12 carbon atoms.

[0058] The content of component (B) is preferably 20 to 80 parts by mass per 100 parts by mass of component (A). This configuration reduces the melt viscosity of the resin composition, improving the embeddability in wiring and improving heat resistance and heat resistance reliability. While not particularly limited, the content of component (B) is more preferably 25 to 75 parts by mass, and even more preferably 30 to 70 parts by mass per 100 parts by mass of component (A).

[0059] The resin composition preferably contains 3 to 40 parts by mass of component (B) per 100 parts by mass of the resin components, more preferably 5 to 30 parts by mass, and particularly preferably 10 to 25 parts by mass. When the content of component (B) per 100 parts by mass of the resin components is within this range, the melt viscosity of the resin composition is reduced, improving the embeddability in wiring, while preventing a decrease in the heat resistance and heat reliability of the cured product and a deterioration in dielectric properties. The content of component (B) and its content in the resin components can be measured, for example, by infrared spectroscopy (FTIR) or gas chromatography mass spectrometry.

[0060] An example of the component (B) that has an isocyanuric ring structure and two allyl groups in one molecule and is liquid at 25° C. is "L-DAIC," a product name manufactured by Shikoku Chemical Industries, Ltd.

[0061] [Component (C)] Component (C) is a thermoplastic resin. While the thermoplastic resin used as component (C) is not particularly limited, it is preferably a thermoplastic elastomer having a dielectric dissipation factor (tan δ) of less than 0.005 in the frequency range of 1 to 100 GHz. This contributes to the excellent dielectric properties of the thermosetting film formed from the resin composition of this embodiment in the high-frequency range. The "thermoplastic elastomer having a dielectric dissipation factor (tan δ) of less than 0.005 in the frequency range of 1 to 100 GHz" is preferably a styrene-based thermoplastic elastomer. Examples of styrene-based thermoplastic elastomers include block copolymers containing a block of styrene or an analog thereof as at least one terminal block and an elastomer block of a conjugated diene as at least one intermediate block. Examples include styrene / butadiene / styrene block copolymer (SBS), styrene / butadiene / butylene / styrene block copolymer (SBBS), styrene / ethylene / butylene / styrene block copolymer (SEBS), styrene / ethylene / ethylene / propylene / styrene block copolymer (SEEPS), etc. The inclusion of a styrene-based thermoplastic elastomer can impart flexibility to the resin composition, maintain the toughness of the cured product, improve adhesion, and reduce dielectric properties.

[0062] The thermoplastic resin of component (C) is more preferably a styrene / ethylene / butylene / styrene block copolymer (SEBS), a styrene / ethylene / ethylene / propylene / styrene block copolymer (SEEPS), etc. By including such a styrene-based thermoplastic elastomer as component (C), which is a hydrogenated styrene-based thermoplastic elastomer, the dielectric properties and heat resistance reliability can be improved (the rate of change of the dielectric dissipation factor (tan δ) can be reduced).

[0063] The content of component (C) is not particularly limited, but when component (C) is included, the resin composition preferably contains 20 to 80 parts by mass of component (C) per 100 parts by mass of the total resin components, more preferably 30 to 70 parts by mass, and even more preferably 40 to 60 parts by mass. By containing component (C) in this range, the heat resistance reliability of the resin composition can be improved (the rate of change of the dielectric dissipation factor (tanδ) can be reduced), and the solder heat resistance can be further improved.

[0064] The number-average molecular weight of the thermoplastic resin of component (C) is preferably 30,000 or more, more preferably 40,000 or more, and even more preferably 50,000 or more. The number-average molecular weight of the thermoplastic resin of component (C) is preferably 30,000 to 150,000, more preferably 40,000 to 120,000, and particularly preferably 50,000 to 100,000. Having a number-average molecular weight within this range improves solder heat resistance. Note that as the molecular weight of the thermoplastic resin of component (C) increases, the melt viscosity of the resin composition tends to increase, resulting in poor embeddability in substrates. However, by including component (B), a compound having an isocyanuric ring structure and two allyl groups per molecule and liquid at 25°C, the melt viscosity of the resin composition can be reduced and its embeddability in wiring can be improved, even when a thermoplastic resin with a high molecular weight is used.

[0065] [Component (D)] Component (D) is an inorganic filler. The inorganic filler is required to have insulating properties and a low thermal expansion coefficient. A common inorganic filler can be used as the inorganic filler. Examples of inorganic fillers include silica, alumina, aluminum nitride, calcium carbonate, aluminum silicate, magnesium silicate, magnesium carbonate, barium sulfate, barium carbonate, lime sulfate, aluminum hydroxide, calcium silicate, potassium titanate, titanium oxide, zinc oxide, silicon carbide, silicon nitride, and boron nitride. The inorganic filler may be used alone or in combination of two or more. In particular, silica filler is preferred from the viewpoint of low thermal expansion coefficient and low dielectric properties.

[0066] The inorganic filler may be surface-treated with a silane coupling agent having one or more functional groups selected from acrylic, methacrylic, styryl, amino, epoxy, vinyl, ureido, mercapto, isocyanate, and sulfide, or a silane coupling agent having a long-chain hydrocarbon group. For example, the inorganic filler is preferably surface-treated with a surface treatment agent such as an aminosilane coupling agent, a ureidosilane coupling agent, an epoxysilane coupling agent, a mercaptosilane coupling agent, a vinylsilane coupling agent, a styrylsilane coupling agent, a (meth)acrylatesilane coupling agent, an isocyanatesilane coupling agent, a sulfidesilane coupling agent, an octylsilane coupling agent, an octenylsilane coupling agent, an organosilazane compound, or a titanate coupling agent to improve its moisture resistance, dispersibility, etc. These may be used alone or in combination of two or more. More preferably, among surface-treated silica fillers, it is preferable to use a silica filler that has been surface-treated with a vinylsilane coupling agent. By using a silica filler that has been surface-treated with a vinylsilane coupling agent, it is possible to improve the toughness and adhesiveness of the cured product by reacting with component (A) and component (B). It is also preferable to use a silica filler that has been surface-treated with a silane coupling agent having a long-chain hydrocarbon group. By using a silica filler that has been surface-treated with a silane coupling agent having a long-chain hydrocarbon group, it is possible to improve the moisture resistance of the cured product.

[0067] The shape of the inorganic filler is not particularly limited, and examples include spherical, flaky, needle-like, and amorphous shapes. Spherical shapes are preferred from the viewpoints of high filling and dispersibility of the inorganic filler in the resin composition, the fluidity of the resin composition, and a low thermal expansion coefficient of the cured product. The average particle diameter is preferably 0.05 to 20 μm, more preferably 0.1 to 15 μm, and even more preferably 0.5 to 10 μm. Having the average particle diameter of the inorganic filler within this range provides excellent embedding ability between the microstructures of substrates and electronic components. It also enables the resin composition to be formed into a thin film. The average particle diameter is the particle diameter at 50% of the cumulative value in the particle size distribution on a volume basis, measured by laser diffraction / scattering. The average particle diameter can be measured, for example, using a laser scattering / diffraction particle size distribution analyzer: LS13320 (manufactured by Beckman Coulter, Inc., wet type).

[0068] When the resin composition contains the (D) component, the content is not particularly limited, but the (D) component is preferably contained in an amount of 50% by mass or more, more preferably 60% by mass or more, and even more preferably 65% ​​by mass or more, based on 100% by mass of the nonvolatile components in the resin composition. This configuration reduces the thermal expansion coefficient. More specifically, by having the (D) component content within the above range, the linear expansion coefficient α1 of the cured resin composition below the glass transition temperature and the linear expansion coefficient α2 of the cured resin composition above the glass transition temperature can be reduced. Furthermore, the (D) component is preferably contained in an amount of 50 to 95% by mass, more preferably 60 to 90% by mass, and even more preferably 65 to 85% by mass, based on 100% by mass of the nonvolatile components in the resin composition. By having the (D) component content within the above range, the linear expansion coefficient α2 above the glass transition temperature can be reduced, thereby reducing stress during heat resistance reliability testing of multilayer substrates.

[0069] In addition, when the resin composition contains 50% by mass or more of the component (D) as described above in order to reduce the thermal expansion coefficient of the resin composition, the melt viscosity of the resin composition increases when the inorganic filler is highly loaded, which tends to reduce the embeddability into a substrate. However, by including the component (B), which is a compound having an isocyanuric ring structure and two allyl groups in one molecule and which is liquid at 25°C, the melt viscosity of the resin composition can be reduced and the embeddability into wiring can be improved, even when the inorganic filler is highly loaded.

[0070] The silica filler used in component (D) is not particularly limited and may include fused silica, ordinary silica, spherical silica, crushed silica, crystalline silica, amorphous silica, etc. From the viewpoints of dispersibility of the silica filler, flowability of the thermosetting resin composition, surface smoothness of the cured product, dielectric properties, low thermal expansion coefficient, adhesiveness, etc., spherical fused silica is desirable.

[0071] The method for surface treating the silica filler with the above-mentioned coupling agent is not particularly limited, and examples thereof include a dry method and a wet method.

[0072] The dry method is a method in which silica filler and an appropriate amount of silane coupling agent relative to the surface area of ​​the silica filler are placed in a stirring device, and stirring is performed under appropriate conditions, or the silica filler is placed in a stirring device in advance, and while stirring under appropriate conditions, an appropriate amount of silane coupling agent relative to the surface area of ​​the silica filler is added by dropping or spraying in the form of a liquid or solution, and the silane coupling agent is uniformly attached to the surface of the silica filler by stirring, and the surface is treated (by hydrolysis).As the stirring device, for example, a mixer that can stir and mix at high speed such as a Henschel mixer can be mentioned, but it is not particularly limited.

[0073] The wet method is a method in which a sufficient amount of silane coupling agent is dissolved in water or an organic solvent relative to the surface area of ​​the silica filler to be surface treated, and the silica filler is added to the surface treatment solution, which is then stirred to form a slurry, thereby allowing the silane coupling agent and the silica filler to react sufficiently.The silica filler is then separated from the surface treatment solution using filtration, centrifugation, etc., and heated and dried to perform the surface treatment.

[0074] [Component (E)] Component (E) is a curing catalyst. The curing catalyst as component (E) is an additive for satisfactorily initiating the reaction between components (A) and (B). By including such component (E), the degree of curing of the resin composition for a certain curing temperature and time can be improved. For this reason, it is preferable that the resin composition of this embodiment further includes a curing catalyst as component (E).

[0075] The curing catalyst for component (E) may be any that induces a curing reaction between components (A) and (B), and a conventionally known reaction initiator (e.g., a polymerization initiator) may be used. For example, curing catalysts include organic peroxides and azo compounds. Examples of curing catalysts for component (E) include organic peroxides manufactured by NOF Corporation, such as those under the trade names "Percumyl D" and "Perbutyl C." The component (E) may be used alone or in combination of two or more.

[0076] Furthermore, when component (E) is contained, the content of component (E) is preferably 0.1 to 5 parts by mass per 100 parts by mass of the total resin components of the resin composition. By configuring in this manner, it is possible to satisfactorily improve heat resistance and adhesiveness. Although not particularly limited, the content of component (E) is more preferably 0.1 to 4 parts by mass, and even more preferably 0.1 to 3 parts by mass, per 100 parts by mass of the total resin components of the resin composition.

[0077] [Component (F)] Component (F) is an antioxidant. The antioxidant of component (F) is an additive for improving heat resistance reliability. By including such component (F), it is possible to improve heat resistance reliability.

[0078] [Component (G)] The component (G) is a silane coupling agent. By adding the silane coupling agent as the component (G), adhesion can be improved.

[0079] [Other Components] The resin composition of this embodiment may further contain components other than the components (A) to (E) described above. Examples of other components include various additives such as solvents, dispersants, antifoaming agents, leveling agents, thixotropic agents, flame retardants, and fluxes.

[0080] [Method for Producing Resin Composition] The resin composition of this embodiment can be produced by a conventional method, for example, by dissolving, mixing, and dispersing the components described above together with a solvent using a bead mill, a Raikai mill, a pot mill, a three-roll mill, a rotary mixer, a twin-screw mixer, a dissolver, a stirrer, or the like.

[0081] [Uses of Resin Composition] The resin composition of this embodiment can be suitably used as a resin composition for protective agents, adhesives, and adhesive films used in electronic components. The resin composition of this embodiment can also be suitably used as an interlayer bonding sheet or interlayer adhesive for multilayer wiring boards. When the resin composition of this embodiment is used for various applications for electronic components, there are no particular restrictions on the electronic components to be bonded, and examples include various printed wiring boards such as ceramic substrates and organic substrates, various electronic components, semiconductor chips, and semiconductor devices.

[0082] Adhesive films, interlayer bonding sheets, interlayer adhesives, etc. using the resin composition of this embodiment are contained as cured products of the resin composition in laminates and semiconductor devices that constitute electronic components, etc. Therefore, laminates and semiconductor devices that constitute electronic components, etc. preferably contain a cured product of the resin composition of this embodiment.

[0083] The resin composition of the present embodiment can also be used as a prepreg using the resin composition, or as a high frequency electronic component having a cured product of the resin composition.

[0084] [Elastic Modulus at Room Temperature (25°C)] The resin composition of this embodiment preferably has an elastic modulus at room temperature (25°C) of 1.0 to 15.0 GPa, more preferably 1.5 to 12.0 GPa, even more preferably 2.0 to 10.0 GPa, and particularly preferably 4.1 to 9.0 GPa. When the elastic modulus at 25°C is within the above range, the surface of the cured product is less susceptible to scratches, and a cured product with high hardness can be obtained. On the other hand, if the elastic modulus is lower than the above range, the cured product will be soft, and defects such as scratches and breakage may occur in the cured product during the process of producing a wiring board.

[0085] [Elastic Modulus at 200°C] From the viewpoint of reducing the occurrence of stress and distortion when heated, the resin composition of the present embodiment preferably has an elastic modulus at 200°C of 0.1 to 5.0 GPa, more preferably 0.1 to 3.0 GPa, and even more preferably 0.1 to 2.0 GPa.

[0086] [Glass Transition Temperature (Tg)] The resin composition of this embodiment preferably has a glass transition temperature of 120 to 170°C, more preferably 130 to 165°C, even more preferably 135 to 160°C, and particularly preferably 140 to 158°C. Having a glass transition temperature within the above range allows for a cured product to be obtained that has flexibility sufficient to accommodate deformation and has good impact resistance. If the glass transition temperature is higher than the above range, the cured product is likely to become brittle, and defects such as scratches, chips, and cracks may occur in the cured product during the process of producing a wiring board. On the other hand, if the glass transition temperature is lower than the above range, stress may be generated during a reliability test (e.g., a thermal cycling test) of the multilayer board, which may cause problems during the reliability test.

[0087] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. In the following examples, parts and % represent parts by mass and % by mass unless otherwise specified.

[0088] (Examples 1 to 16, Comparative Examples 1 to 5) [Sample Preparation] Each component other than component (D) and component (E) was weighed out to the blending ratio (parts by mass) shown in Tables 1 to 5 below, and then placed in a dissolving container together with a specified solvent. With the lid on, the container was heated to 70°C and mixed under normal pressure for 3 to 6 hours while stirring at 100 to 400 rpm using a stirrer. After cooling to room temperature, component (D) was added and mixed at 100 to 400 rpm for 1 hour, followed by dispersion using a bead mill. Then, component (E) was added and mixed at 100 to 400 rpm using a stirrer for 1 hour. In this manner, dissolved dispersions containing the resin compositions of Examples 1 to 16 and Comparative Examples 1 to 5 were prepared.

[0089] The raw materials used in preparing the dissolved dispersions containing the resin compositions in Examples 1 to 16 and Comparative Examples 1 to 5 are as follows.

[0090] [Component (A)] (A1): Polyphenylene ether resin having a group represented by formula (1) at its terminal, manufactured by SABIC Innovative Plastics, trade name "Noryl SA9000", Mn: 1850 to 1950. [Component (A')] (A'2): Polyphenylene ether resin not having a group represented by formula (1) at its terminal, manufactured by Mitsubishi Gas Chemical Company, Inc., trade name "OPE-2St 2200", Mn: 2200.

[0091] [Component (B): Compound having an isocyanuric ring structure and two allyl groups in one molecule] (B1): Shikoku Chemical Industry Co., Ltd., trade name "L-DAIC", a compound represented by the above formula (2). In the above formula (2), R ２ is an alkyl group having 4 to 14 carbon atoms. [Component (B'): a compound other than component (B) that has an allyl group in one molecule] (B'2): Mitsubishi Chemical Corporation, trade name "TAIC", a compound that has an isocyanuric ring structure and three allyl groups in one molecule.

[0092] [Component (C): Thermoplastic Resin] (C1): Hydrogenated styrene-based thermoplastic elastomer (SEBS) manufactured by Kraton Polymers, trade name "Kraton G1652", Mn: 54,000. (C2): Hydrogenated styrene-based thermoplastic elastomer (SEEPS) manufactured by Kuraray, trade name "Septon 4033", Mn: 74,000. (C3): Hydrogenated styrene-based thermoplastic elastomer (SEBS) manufactured by Kuraray, trade name "Septon 8004", Mn: 76,000.

[0093] [Component (D): Inorganic Filler] (D1): Spherical silica surface-treated with 7-octenyltrimethoxysilane (a silane coupling agent manufactured by Shin-Etsu Chemical Co., Ltd. under the trade name "KBM-1083") (the spherical silica used was manufactured by Denka under the trade name "FB-3SDX (average particle size 3 μm)"). (D2): Spherical silica surface-treated with octyltriethoxysilane (a silane coupling agent manufactured by Shin-Etsu Chemical Co., Ltd. under the trade name "KBE-3083") (the spherical silica used was manufactured by Denka under the trade name "FB-3SDX (average particle size 3 μm)"). (D3): Spherical silica not surface-treated with a silane coupling agent (the spherical silica used was manufactured by Denka under the trade name "FB-3SDX (average particle size 3 μm)". (D4): Spherical silica surface-treated with a silane coupling agent KBM-1003 (manufactured by Admatechs Co., Ltd., product name "10SV-C12 (average particle size 1 μm)" was used). (D5): Spherical silica surface-treated with a silane coupling agent KBM-1083 (manufactured by Admatechs Co., Ltd., product name "20SV-C9 (average particle size 2 μm)" was used).

[0094] [Component (E): Curing catalyst] (E1): Product name "Perkmyl D" manufactured by NOF Corporation.

[0095] [Component (F): Antioxidant] (F1): A hindered phenol-based antioxidant (melting point 220-222°C), product name "AO-20", manufactured by ADEKA Corporation. (F2): A hindered phenol-based antioxidant (melting point 51-54°C), product name "AO-50", manufactured by ADEKA Corporation.

[0096] [Component (G): Silane Coupling Agent] (G1): Silane coupling agent (bis(triethoxysilylpropyl)tetrasulfide), product name "Kabras 4", manufactured by Osaka Soda Co., Ltd.

[0097] The "Total Resin Components" column in Tables 1 to 4 shows the total amount (parts by mass) of the components corresponding to the resin components among the raw materials used to prepare the resin compositions. The "Total Solid Content" column in Tables 1 to 4 shows the total amount (parts by mass) of the components corresponding to the solid content among the raw materials used to prepare the resin compositions. The "Filler Ratio (Wt%)" column in Tables 1 to 4 shows the ratio (% by mass) of component (D) in the solid content raw materials used to prepare the resin compositions.

[0098] The dissolved dispersions containing the resin compositions of Examples 1 to 11 and Comparative Examples 1 to 5 obtained as described above were evaluated and measured for "heat resistance reliability," "solder heat resistance," and "substrate pattern embeddability" using the methods described below. For each evaluation and measurement, a resin film was prepared using the following method, and the prepared resin film was used for evaluation and measurement. First, the dissolved dispersion containing each resin composition was applied to a release-treated PET film using a knife. The dissolved dispersion on the PET film was then dried at a temperature of 80 to 130°C to prepare a resin film with a thickness of 50 to 100 μm. The results are shown in Tables 1 to 4.

[0099] [Heat Resistance Reliability] [Initial Values ​​(Dielectric Constant (ε) and Dielectric Loss Tangent (tan δ))] The resin film prepared by the method described above was cured at a temperature of 200°C for 1 hour under a pressure of 1 MPa to prepare a sample for measuring the dielectric constant (ε) and dielectric loss tangent (tan δ). The dielectric constant (ε) and dielectric loss tangent (tan δ) of the prepared sample were measured using a 10 GHz resonator according to the SPDR method. The dielectric constant (ε) is preferably less than 3.50, and more preferably less than 3.25. The dielectric loss tangent is preferably less than 0.003, and more preferably less than 0.002.

[0100] [Changes (%) relative to the initial values ​​after 125°C x 1000 hours (dielectric constant (ε) and dielectric loss tangent (tan δ)] The cured resin film, whose dielectric properties (initial values) had been measured as described above, was left at 125°C for 1000 hours, and then the dielectric constant (ε) and dielectric loss tangent (tan δ) after 125°C x 1000 hours were measured at room temperature and humidity using a 10 GHz resonator according to the SPDR method. The changes (%) relative to the initial values ​​for the measured dielectric constant (ε) and dielectric loss tangent (tan δ) after 125°C x 1000 hours were calculated. The changes (%) relative to the initial values ​​were calculated by dividing the difference between each measured value after 1000 hours and the initial value by the initial value and multiplying the result by 100.

[0101] [Soldering Heat Resistance (280°C, 290°C, 300°C)] The resin film prepared by the method described above was sandwiched between 18 μm thick copper foil and cured at 200°C for 1 hour under a pressure of 3 MPa to prepare a sample (double-sided copper-laminated board) for evaluating soldering heat resistance. The prepared double-sided copper-laminated board was cut into 25 mm squares and floated in a solder bath at 280°C, 290°C, or 300°C for 1 minute each. During this time, the appearance of each sample was visually inspected and evaluated based on the following evaluation criteria. An evaluation result of "◯" was deemed to be acceptable. ◯: No change. ×: Blistering and copper foil peeling were observed.

[0102] [Substrate Pattern Embeddability] A substrate for embeddability evaluation was prepared by patterning a 0.1 mm thick FR4 (manufactured by Panasonic) copper foil with a thickness of 35 μm using a conventional method, as shown in Fig. 1. Fig. 1 is a plan view showing the patterning used in the evaluation of substrate pattern embeddability. L / S in Fig. 1 indicates line and space.

[0103] Next, the resin film and copper foil (18 μm) were cut into 100 × 100 mm pieces, and the copper foil, resin film, embeddability evaluation substrate, resin film, and copper foil were laminated in this order. This was cured at a temperature of 200°C for 1 hour under a pressure of 3 MPa, and then the copper foil on one side was etched away to expose the surface of the resin film. The appearance of the resin film was observed to evaluate the embeddability.

[0104] Figure 2 shows a photographic example of good embeddability, and Figure 3 shows a photographic example of poor embeddability. As shown in Figure 3, when the embeddability is poor and there are areas where the resin film is not embedded between the patterns (poorly embedded areas), the color of the poorly embedded areas is observed to be whitish in patches. An evaluation result of "◯" is considered to be pass. ◯: No poorly embedded areas are observed. ×: Poorly embedded areas are observed.

[0105] Furthermore, the dispersions containing the resin compositions of Examples 7 and 12 to 16 were evaluated and measured for "modulus of elasticity at room temperature (25°C)," "modulus of elasticity at 200°C," and "glass transition temperature (Tg)" by the methods described below. The evaluation results are shown in Table 5.

[0106] <<Evaluation of Elastic Modulus>> Measurement was carried out by dynamic mechanical analysis (DMA). Specifically, the film was heat-cured at 200°C and peeled from the support, and then a test piece (10±0.5 mm x 40±1 mm) was cut out from the adhesive film, and the width and thickness of the test piece were measured. Then, measurements were carried out using a DMS6100 (3°C / min, 23-250°C, 10 Hz). The storage modulus at 25°C was defined as the "elastic modulus at room temperature (25°C)," and the storage modulus at 200°C was defined as the "elastic modulus at 200°C."

[0107] Glass Transition Temperature (Tg) Measurement was performed using the dynamic mechanical analysis (DMA) described above. Specifically, the film was heat-cured at 200°C and peeled from the support. Test pieces (10±0.5 mm x 40±1 mm) were then cut from the adhesive film, and the width and thickness of the test pieces were measured. Measurement was then performed using a DMS6100 (3°C / min, 23-250°C, 10 Hz). The peak temperature of tan δ was read and used as Tg.

[0108] <Impact Resistance> Ball impact drop strength was measured. Specifically, the film was heat-cured at 200°C to prepare a test piece measuring 20 mm x 30 mm and 1 mm thick. This test piece was placed on an iron plate, and an alumina ball weighing 25 g was dropped from a height of 50 cm onto it to perform an impact resistance test. Three tests were conducted, and samples that did not crack in any of the tests were rated as good.

[0109]

[0110]

[0111]

[0112]

[0113]

[0114] [Results] As shown in Tables 1 and 2, for Examples 1 to 10, by using SA-9000 as component (A), the rate of change in tan δ was 20% or less in terms of heat resistance reliability, and the solder heat resistance was good, passing at 300° C. Furthermore, by using L-DAIC as component (B), the board embeddability was good, passing.

[0115] Comparative Example 1, in which the component (A) of Example 7 was replaced with OPE-2ST 2200, exhibited a large change in tan δ of 58.9% for heat resistance reliability, making it inferior in this respect. Comparative Example 2, in which the component (B) of Example 1 was replaced with TAIC, exhibited a large initial value of tan δ of 0.0022, more than 0.002, making it inferior in this respect. Comparative Example 3, in which the component (A) of Example 1 was replaced with OPE-2ST 2200, exhibited a large change in tan δ of 24.1%, more than 20%, for heat resistance reliability, and also failed the soldering heat resistance test at 280°C, making it inferior in this respect. Similarly, Comparative Example 1, which also used OPE-2ST 2200, passed the soldering heat resistance test at 300°C. This is because Comparative Example 3 used the component (G), Kabras 4, which made the difference in heat resistance between SA-9000 and OPE-2ST 2200 more pronounced. Comparative Example 4, in which the L-DAIC of component (B) was further removed from Comparative Example 3 and the lost amount was replaced with component (C), had poor solder heat resistance similar to Comparative Example 3, and furthermore, the board pattern embeddability was unacceptable.

[0116] Table 4 shows the case where the inorganic filler (D) component is not used. With regard to heat resistance reliability, the rate of change in tan δ was 176.8% in Example 11, which used SA-9000 as the (A) component, while it was 222.2% in Comparative Example 5, which used OPE-2St 2200, making Example 11 superior. Furthermore, with regard to solder heat resistance, Example 11 passed at 300°C, while Comparative Example 5 failed at 300°C. With regard to board pattern embeddability, both Example 11 and Comparative Example 5 passed because they used L-DAIC as the (B) component. Regarding the heat resistance reliability of ε, the change was generally small, and all Examples and Comparative Examples were good.

[0117] As shown in Table 5, in Example 7 and Examples 12 to 16, the modulus of elasticity at room temperature (25°C) was 4.1 to 9.0 GPa or less, and the modulus of elasticity at 200°C was 0.1 to 2.0 GPa or less, which were good. Furthermore, the glass transition temperatures of Examples 7 and Examples 12 to 16 were in the range of 140 to 158°C, which were good. Furthermore, no defects such as cracks were observed in any of the examples regarding impact resistance.

[0118] The resin composition of the present invention can be used as a resin composition for adhesives or adhesive films used in electronic components. The resin composition of the present invention can also be used as a bonding sheet or interlayer adhesive for interlayer bonding of multilayer wiring boards. The resin composition of the present invention can also be used as a prepreg using a cured product of the resin composition, or as a high-frequency electronic component having a cured product of the resin composition.

Claims

1. (A) a polyphenylene ether resin having a group represented by the following formula (1) at its terminal; (B) a compound having an isocyanuric ring structure and two allyl groups in one molecule and being liquid at 25°C; A resin composition comprising: 【Chemistry 1】 (In the above formula (1), R １ represents a hydrogen atom or an alkyl group.

2. The resin composition according to claim 1, wherein the component (B) is a compound represented by the following formula (2): 【Chemistry 2】 (In the above formula (2), R ２ is an alkyl group having 4 to 14 carbon atoms.

3. The resin composition according to claim 1 or 2, further comprising (C) a thermoplastic resin having a number average molecular weight of 30,000 or more.

4. The resin composition according to claim 3, wherein the component (C) is a thermoplastic elastomer having a dielectric tangent (tan δ) of less than 0.005 in a frequency range of 1 to 100 GHz.

5. The resin composition according to claim 3, comprising 20 to 80 parts by mass of the (C) component per 100 parts by mass of the total of the resin components.

6. The resin composition according to claim 1 or 2, further comprising (D) an inorganic filler.

7. The resin composition according to claim 6, wherein the resin composition contains 50% by mass or more of the component (D) based on 100% by mass of nonvolatile components.

8. The resin composition according to claim 7, wherein the resin composition contains 60 to 90% by mass of the (D) component based on 100% by mass of non-volatile components.

9. The resin composition according to claim 1 or 2, further comprising a curing catalyst (E).

10. The resin composition according to claim 1 or 2, comprising 10 to 50 parts by mass of the (A) component per 100 parts by mass of the total of the resin components.

11. The resin composition according to claim 1 or 2, comprising 3 to 40 parts by mass of the (B) component per 100 parts by mass of the total of the resin components.

12. A cured product of the resin composition according to claim 1 or 2.

13. A prepreg using the resin composition according to claim 1 or 2.

14. A printed wiring board having a cured layer made of the resin composition according to claim 1 or 2.

15. A high frequency electronic component comprising the cured product according to claim 12.

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