Curable compositions, cured products, prepregs, circuit boards, multilayer films, semiconductor sealing materials, and semiconductor devices.

Abstract

The purpose of this disclosure is to provide curable compositions, cured products, prepregs, circuit boards, multilayer films, semiconductor sealing materials, and semiconductor devices that exhibit low dielectric loss tangent and low moisture absorption upon curing. This disclosure pertains to a curable composition characterized by comprising a first maleimide compound (A1) and a second maleimide compound (A2) having structural units different from those contained in the first maleimide compound (A1), wherein the second maleimide compound (A2) is a compound having a monocyclic or condensed polycyclic aromatic group and a maleimide group linked to two or more straight-chain or branched alkylene groups.

Description

Technical Field

[0001] This disclosure relates to curable compositions, cured products, prepregs, circuit boards, multilayer films, semiconductor sealing materials, and semiconductor devices. Background Technology

[0002] Prepregs, obtained by impregnating glass cloth with thermosetting resins such as epoxy resins or BT (bismaleimide-triazine) resins and drying them by heating, laminates obtained by heating and curing the prepregs, and multilayer boards obtained by combining the laminates and the prepregs and heating and curing them are widely used as circuit board materials for electronic devices. Among them, as the packaging substrate, which serves as an interposer for mounting semiconductors, continues to become thinner, warpage of the packaging substrate during mounting has become a problem. Therefore, materials with high heat resistance are needed to suppress warpage of the packaging substrate during mounting.

[0003] Furthermore, the increasing speed and frequency of signals in recent years has created a demand for thermosetting compositions capable of forming cured materials that maintain sufficiently low dielectric constants and exhibit sufficiently low dielectric loss tangents under these conditions. Particularly recently, there has been a demand for materials and compositions with improved properties, such as heat resistance and dielectric characteristics, in various electrical material applications, especially advanced materials applications. Maleimide resins have attracted attention as materials that combine heat resistance with low dielectric constants and low dielectric loss tangents to meet these requirements. However, while conventional maleimide resins exhibit high heat resistance, they also suffer from high hygroscopicity, and their dielectric properties (dielectric constant and dielectric loss tangent) do not meet the levels required for advanced materials applications.

[0004] For example, Patent Document 1 discloses a thermosetting resin composition containing a polymaleimide resin having an indane ring and triallyl cyanurate or an aromatic diamine as a material for printed circuit boards that does not impair heat resistance and has a dielectric constant of 4.0 or less as a laminate.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 5-247202 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] However, the thermosetting resin composition in Patent Document 1 does not discuss the dielectric loss tangent, thus failing to meet the level required for advanced material applications. Furthermore, it does not balance a high glass transition temperature with a low dielectric loss tangent. Additionally, transmission loss increases with higher frequencies, therefore, circuit board materials require reduced transmission loss in high-frequency regions. However, Patent Document 1 only discusses the dielectric properties in currently utilized frequency bands (ranging from several hundred MHz to 3 GHz), without addressing whether it can handle technologies used in 5G mobile communication systems utilizing frequency bands above Sub-6 (e.g., 3.6 GHz and above).

[0010] Therefore, the technical problem to be solved by this disclosure is to provide a curable composition, cured product, prepreg, circuit board, multilayer film, semiconductor sealing material and semiconductor device that is difficult to crack during curing and exhibits low dielectric loss tangent and high glass transition temperature.

[0011] Methods for solving problems

[0012] In order to solve the above-mentioned problems, the inventors have repeatedly conducted in-depth research and discovered that by using a curable composition containing a first maleimide compound (A1) and a second maleimide compound (A2) having structural units different from those contained in the first maleimide compound (A1), and wherein the second maleimide compound (A2) is a compound having a monocyclic or condensed polycyclic aromatic group and a maleimide group connected with two or more straight-chain or branched alkylene groups, cracking during curing is reduced and low dielectric loss tangent and high glass transition temperature are exhibited, thus completing the present invention.

[0013] The effects of the invention

[0014] According to this disclosure, a curable composition, cured product, prepreg, circuit board, multilayer film, semiconductor sealing material, and semiconductor device that are difficult to crack during curing and exhibit low dielectric loss tangent and high glass transition temperature can be provided.

[0015] According to this disclosure, a curable composition, cured product, prepreg, circuit board, multilayer film, semiconductor sealing material, and semiconductor device can be provided that are difficult to crack even when cured in frequency bands above Sub6 and exhibit low dielectric loss tangent and high glass transition temperature. Such a curable composition is particularly useful in applications such as sealing materials for electronic components. Attached Figure Description

[0016] Figure 1A The results of GPC determination for the polymaleimide compound (X) of Synthesis Example 1 are shown.

[0017] Figure 1B The results of FD-MS analysis of the polymaleimide compound (X) of Synthetic Example 1 are shown.

[0018] Figure 1C The NMR results represent the polymaleimide compound (X) synthesized in Example 1. Detailed Implementation

[0019] Hereinafter, embodiments of the present invention (referred to as "this embodiment") will be described in detail, but this disclosure is not limited to the following description and various modifications can be made within its scope.

[0020] [the term]

[0021] In this specification, "reaction material" refers to a compound that partially constitutes the chemical structure of the target compound and is used to obtain the target compound through a chemical reaction such as combination or decomposition. It does not include substances such as solvents or catalysts that act as facilitators in the chemical reaction. Specifically, "reaction material" in this specification refers to, for example, a precursor used to obtain the second maleimide compound (A2) or its precursor compound (e.g., an intermediate amine compound (c) obtained by linking the aforementioned aromatic amine compounds (a) to each other via the aforementioned aromatic divinyl compound (b1)) through a chemical reaction when the target compound is used.

[0022] The term "aromatic group" in this specification preferably refers to an aromatic ring having 3 to 30 carbon atoms, and more preferably an aromatic ring having 4 to 26 carbon atoms. Furthermore, for the "aromatic group" in this specification, the hydrogen atoms of the aromatic ring in the aromatic group may be replaced by substituents (e.g., alkyl groups having 1 to 10 carbon atoms, alkoxy groups having 1 to 10 carbon atoms, or halogen atoms). Additionally, the "aromatic group" includes heteroaromatic groups, and the -CH2- or -CH= in the "aromatic group" may be replaced by -O-, -S-, or -N= in a non-adjacent manner.

[0023] Examples of aromatic ring types include monocyclic aromatic rings and condensed polycyclic aromatic rings.

[0024] Examples of monocyclic aromatic rings include benzene, furan, pyrrole, thiophene, imidazole, pyrazole, oxazole, isoxazole, thiazole, isothiazole, pyridine, pyrimidine, pyridazine, pyrazine, and triazine. Examples of condensed polycyclic aromatic rings include naphthalene, anthracene, phenatene, quinoline, isoquinoline, quinazoline, phthalazine, teridine, coumarin, indole, benzimidazole, benzofuran, and acridine. Furthermore, the hydrogen atoms of the aromatic ring in the aromatic group may be substituted, for example, with alkyl, alkenyl, alkoxy, aryl, aralkyl, or halogen atoms having 1 to 10 carbon atoms.

[0025] It should be noted that a monovalent aromatic group refers to a group obtained by removing one hydrogen atom from an aromatic group, a divalent aromatic group refers to a group obtained by removing any two hydrogen atoms from an aromatic group, and a trivalent to hexavalent aromatic group refers to a group obtained by removing three to six hydrogen atoms from an aromatic group.

[0026] As used in this specification, "cyclic hydrocarbon group" can be exemplified by diphenylene, terphenylene, or groups having one or more benzene rings and one or more indene rings. For example, groups represented by the following general formula (M) can be used as examples of groups having one or more benzene rings and one or more indene rings.

[0027]

[0028] (In formula (M), R) b Each of the following groups independently represents an alkyl, alkoxy, or alkylthio group having 1 to 10 carbon atoms; an aryl, aryloxy, or arylthio group having 6 to 10 carbon atoms; a cycloalkyl, halogen, hydroxyl, or mercapto group having 3 to 10 carbon atoms; q A1 and q A2 Each q represents an integer value from 0 to 3 independently. A1 and q A2 When R is 2 to 3, b Within the same ring, they can be the same or different. A1 (This represents the average number of repeating units, expressed as a value ranging from 0.95 to 10.0.)

[0029] As used in this specification, "aralkyl" may include, for example, benzyl, diphenylmethyl, naphthylmethyl, etc. The hydrogen atom of the aromatic ring in this aralkyl group may be substituted, for example, with an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a halogen atom. It should be noted that "arylene" may include divalent groups obtained by removing any one hydrogen atom from the aforementioned "aralkyl" group.

[0030] In this specification, "alkyl" can be any of the straight-chain, branched, or cyclic forms, such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, 1,2-dimethylpropyl, n-hexyl, isohexyl, (n)heptyl, (n)octyl, (n)nonyl, (n)decyl, (n)undecyl, (n)dodecyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, or cyclononyl.

[0031] In this specification, "cycloalkyl" may include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, methylcyclobutyl, norbornenyl, or adamantyl, etc.

[0032] In this specification, "alkyl thio" may include methyl thio, ethyl thio, propyl thio, butyl thio, octyl thio, or 2-ethylhexyl thio.

[0033] In this specification, "alkenyl" may include ethynyl, 1-propynyl, 2-propynyl, 2-butynyl, pentylyl, hexynyl, vinyl, allyl, or isopropenyl, etc.

[0034] In this specification, "alkoxy" may include, for example, methoxy, ethoxy, propoxy, isopropoxy, butoxy, pentoxy, hexoxy, 2-ethylhexyloxy, octyloxy, or nonyloxy.

[0035] In this specification, "aryl" may include, for example, phenyl, naphthyl, phenatenyl, anthraceneyl, azulenyl, and naphthyl. Furthermore, for this "aryl" group, the hydrogen atom of the aromatic ring may be substituted, for example, by an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkenyl group having 1 to 10 carbon atoms, or a halogen atom. It should be noted that "arylene" may include divalent groups obtained by removing any one hydrogen atom from the aforementioned "aryl" group.

[0036] In this specification, "aryloxy" may include phenoxy, naphthyloxy, anthraceneyloxy, phenanthryloxy, or pyreneyloxy, etc.

[0037] In this specification, "aryl thio" may include aryl thio groups such as phenyl thio, naphthyl thio, anthracene thio, phenanthryl thio, or pyrene thio.

[0038] The term "halogen atom" in this specification may include, for example, fluorine, chlorine, bromine, or iodine atoms.

[0039] In this specification, "structural unit" refers to the (repeating) unit of a chemical structure formed during a reaction or polymerization. In other words, it refers to the part of the structure in the compound formed by a reaction or polymerization that is not involved in the chemical bonds that participate in the reaction or polymerization, and is referred to as a residue.

[0040] [Curing composition]

[0041] The curable composition of this embodiment is a curable composition containing two or more maleimide compounds. As the maleimide compound, it contains maleimide compound (A2), which has a monocyclic or condensed polycyclic aromatic group and a maleimide group connected to two or more straight-chain or branched alkylene groups.

[0042] In other words, the curable composition of this embodiment is a curable composition containing a first maleimide compound (A1) and a second maleimide compound (A2) (hereinafter referred to as the second maleimide compound (A2)) having structural units different from those contained in the first maleimide compound (A1). The second maleimide compound (A2) is a compound having a monocyclic or condensed polycyclic aromatic group and a maleimide group connected to two or more straight-chain or branched alkylene groups.

[0043] Because it contains a second maleimide compound (A2) with a low proportion of polar functional groups in its chemical structure, the composition as a whole exhibits low dielectric properties and a high glass transition temperature. Furthermore, it exhibits moderate toughness upon curing, thus reducing the likelihood of cracking in the cured product. Additionally, compositions for use in cured products that are difficult to crack even in frequency bands above Sub6 and exhibit low dielectric loss tangent and a high glass transition temperature can be provided.

[0044] It should be noted that by exhibiting a high glass transition temperature, thermal deformation can be suppressed and prevented, and / or heat resistance can be improved.

[0045] In the curable composition of this embodiment, the mixing ratio (parts by mass) of the first maleimide compound (A1) to the second maleimide compound (A2) is preferably 90:10 to 10:90, more preferably 80:20 to 20:80, and even more preferably 75:25 to 25:75. By adjusting the mixing ratio within the above range, a high glass transition temperature and excellent low dielectric loss tangent can be exhibited, which is therefore preferred.

[0046] The curable composition of this embodiment may contain a curing agent (B) as needed, within a range that does not impair the curing properties of the present invention. Furthermore, other resins (C), curing accelerators, or additives, besides the first maleimide compound (A1) and the second maleimide compound (A2), may be added to the curable composition of this embodiment. Examples of such additives include flame retardants, inorganic fillers, silane coupling agents, mold release agents, antioxidants, light stabilizers, heat stabilizers, pigments, and emulsifiers.

[0047] Hereinafter, the first maleimide compound (A1) and the second maleimide compound (A2), which are essential components of the curable composition of this embodiment, will be described in detail, and the curing agent (B), other resins (C), curing accelerators and additives, which are optional components, will be described.

[0048] (First maleimide compound (A1))

[0049] The first maleimide compound (A1) involved in this embodiment is a compound having two or more maleimide groups, and may be a compound with a different chemical structure from the second maleimide compound (A2) described later.

[0050] The first maleimide compound (A1) is a compound formed by two or more maleimide groups linked by a linker group, wherein the linker group is preferably a linear or branched alkylene group having 14 to 30 carbon atoms or a linear or branched alkylene group having 1 to 12 carbon atoms. More specifically, the first maleimide compound (A1) is preferably a compound having a structural unit having two or more maleimide groups of the following general formula (M1) linked to a linker group of the following general formula (M2).

[0051]

[0052] (In the above general formula (M1), Ar) M1 A dashed line indicates an aromatic group; a dotted line indicates its absence or a single bond; an asterisk (*) indicates a bond with another atom (e.g., * in the general formula (M2) below).

[0053] *-L 1 -Ar M2 -L 2 -* (M2)

[0054] (In the above general formula (M2), Ar) M2 L represents a single bond or a cyclic hydrocarbon group. 1 and L 2 Each can be used independently to represent a single bond, or a straight-chain or branched alkylene group; however, L... 1 and L 2Any of them is a linear or branched alkylene group, and * indicates that they are connected to other atoms (e.g., * in the above general formula (M1)).

[0055] It should be noted that in the general formula (M1), the dashed line indicates the absence of a single bond or represents a non-existent bond. When the dashed line is absent, the maleimide group shown in the general formula (M1) can be monovalent. On the other hand, when the dashed line represents a single bond, the maleimide group shown in the general formula (M1) can be divalent.

[0056] As a preferred embodiment of the first maleimide compound (A1) shown in the above general formulas (M1) and (M2), it is preferable to have a compound having two or more maleimide groups shown in the above general formula (M1) linked by one or more linkers shown in the general formula (M2), and more preferably a compound having two or more or five maleimide groups shown in the above general formula (M1) linked by one or more or four or fewer linkers shown in the general formula (M2).

[0057] The preferred first maleimide compound (A1) in this embodiment is preferably a compound having one or more maleimide groups, more preferably a compound having two or more or three maleimide groups, and particularly preferably a bismaleimide compound. From the viewpoint of heat resistance, incorporating a bismaleimide compound into the curable composition is preferable.

[0058] As a specific example of the first maleimide compound (A1) in this embodiment, one or more compounds selected from the group consisting of compounds shown in formulas (A1-1) and (A1-2) are particularly preferred. From the viewpoint of valuing low dielectric loss tangent and water absorption, the first maleimide compound (A1) is more preferably the compound shown in formula (A1-2).

[0059]

[0060] (In the above general formula (A-1), R) A1 and R A2 Each independently represents an alkyl or alkoxy group having 1 to 10 carbon atoms, L 3 Indicates an alkylene group having 1 to 10 carbon atoms, n A1 and n A2 Each of these can be used independently to represent an integer greater than 1 and less than 4.

[0061]

[0062] (In formula (A1-2), R) aEach of the following groups independently represents an alkyl, alkoxy, or alkylthio group having 1 to 10 carbon atoms; an aryl, aryloxy, or arylthio group having 6 to 10 carbon atoms; a cycloalkyl, halogen, nitro, hydroxyl, or mercapto group having 3 to 10 carbon atoms; p A1 and p A2 Represents integer values ​​from 0 to 4. p A1 and p A2 When R is 2 to 4, a Within the same ring, they can be the same or different. R b Each of the following groups independently represents an alkyl, alkoxy, or alkylthio group having 1 to 10 carbon atoms; an aryl, aryloxy, or arylthio group having 6 to 10 carbon atoms; a cycloalkyl, halogen, hydroxyl, or mercapto group having 3 to 10 carbon atoms; q A1 and q A2 Each q represents an integer value from 0 to 3 independently. A1 and q A2 When R is 2 to 3, b Within the same ring, they can be the same or different. A1 (This represents the average number of repeating units, expressed as a value ranging from 0.95 to 10.0.)

[0063] It should be noted that the above q A1 and q A2 and the above p A1 and p A2 When R is 0, a and R b These refer to hydrogen atoms respectively.

[0064] In this embodiment, the compound represented by the above formula (A1-1) can be a commercially available compound or it can be synthesized. For example, examples of commercially available compounds include the BMI series manufactured by Yamato Chemical Co., Ltd., such as 4,4'-diphenylmethane bismaleimide, phenylmethane maleimide, m-phenylene bismaleimide, bisphenol A diphenyl ether bismaleimide, 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide, 4-methyl-1,3-phenylene bismaleimide, or 1,6'-bismaleimide-(2,2,4-trimethyl)hexane, etc.

[0065] The first maleimide compound (A1) has an indane skeleton, resulting in a low proportion of polar functional groups in its structure. Therefore, cured products made using the maleimide compound of the above general formula (A1-2) exhibit excellent dielectric properties and are thus preferred. Furthermore, cured products using conventional maleimide resins tend to be brittle, raising concerns about poor brittleness resistance. However, the maleimide compound of the above general formula (A1-2) has an indane skeleton. Therefore, as a curable composition containing the above general formula (A1-2) and a second maleimide compound (A2) having a monocyclic or condensed polycyclic aromatic group and a maleimide group linked by two or more straight-chain or branched alkylene groups, the curable composition exhibits excellent flexibility and suppleness during curing, and improved brittleness resistance is also expected.

[0066] In addition, R in the above general formula (A1-2) a Preferably, it is any one of alkyl groups having 1 to 4 carbon atoms, cycloalkyl groups having 3 to 6 carbon atoms, or aryl groups having 6 to 10 carbon atoms. By using alkyl groups having 1 to 4 carbon atoms, the planarity and crystallinity near the maleimide group are reduced, thereby increasing the solvent solubility and allowing the cured product to be obtained without impairing the reactivity of the maleimide group. This is a preferred method.

[0067] p in the above general formula (A1-2) A1 and p A2 Each p is preferably 2 to 3, more preferably 2. A1 and p A2 When each is independently 2, the effect of steric hindrance is small, and the electron density on the aromatic ring is increased, making it a preferred method in the production (synthesis) of maleimide.

[0068] In the above general formula (A1-2), q A1 and q A2 R is 0 b Preferably, hydrogen atoms are used; additionally, q A1 and q A2 Each is independently rated as 1 to 3, R b Preferably, it is selected from at least one of the group consisting of alkyl groups having 1 to 4 carbon atoms, cycloalkyl groups having 3 to 6 carbon atoms, and aryl groups having 6 to 10 carbon atoms, particularly through the above-mentioned q A1 and q A2 =0, R b The presence of hydrogen atoms reduces steric hindrance during the formation of the indane skeleton in maleimide, which is advantageous for the manufacture (synthesis) of maleimide and is therefore the preferred method.

[0069] For the first maleimide compound (A1) represented by the above general formula (A1-2), considering the excellent low dielectric constant and low dielectric loss tangent, the molecular weight distribution (weight average molecular weight (Mw) / number average molecular weight (Mn)) calculated by gel permeation chromatography (GPC) is preferably in the range of 1.0 to 4.0, more preferably 1.1 to 3.8, even more preferably 1.2 to 3.6, and particularly preferably 1.3 to 3.4.

[0070] The gel permeation chromatography (GPC) determination method described above is the method described in the Examples section below.

[0071] In the curable composition of this embodiment, the content of the first maleimide compound (A1) relative to 100% by mass of the total curable composition is preferably 5% by mass or more and 95% by mass or less, and most preferably 30% by mass or more and 70% by mass or less. When the content of the first maleimide compound (A1) is in the range of 30% by mass or more and 70% by mass or less, it is preferred from the viewpoint of low dielectric loss tangent.

[0072] (Second maleimide compound (A2))

[0073] The second maleimide compound (A2) involved in this embodiment is a compound having structural units different from those contained in the first maleimide compound (A1), and having a monocyclic or condensed polycyclic aromatic group and a maleimide group connected to two or more straight-chain or branched alkylene groups.

[0074] The aforementioned monocyclic or polycyclic aromatic groups with two or more straight-chain or branched alkylene groups refer to groups containing two or more straight-chain or branched alkylene groups having 1 to 12 carbon atoms, and having one or more of these alkylene groups linked to a single bond on a monocyclic or polycyclic aromatic ring, and being divalent or higher. Therefore, the number of straight-chain or branched alkylene groups linked to the monocyclic or polycyclic aromatic ring is consistent with the valence of the alkylene groups containing the aromatic ring. In this embodiment, the monocyclic or polycyclic aromatic groups with two or more straight-chain or branched alkylene groups are preferably divalent to tetravalent groups, and more preferably divalent to trivalent groups.

[0075] Furthermore, within the molecule of the second maleimide compound (A2) of this embodiment, the structural unit, which differs from the structural unit contained in the first maleimide compound (A1), is preferably a monocyclic or condensed polycyclic aromatic group connected with two or more straight-chain or branched alkylene groups. Therefore, compared to using either compound alone, it exhibits both the low dielectric properties of (A2) and the high glass transition temperature of (A1), demonstrating both low dielectric properties and a high glass transition temperature.

[0076] As a monocyclic or condensed polycyclic aromatic group having two or more straight-chain or branched alkylene groups attached in this embodiment, it is preferably a group represented by the following general formula (I).

[0077]

[0078] (In the above general formula (I), Ar) 1 L represents an aromatic group with a (2+h) valence. 1 L 2 and L 3 Each alkylene group independently represents a carbon group with 1 to 12 carbon atoms; h represents an integer between 0 and 2; and * indicates a bond with another atom.

[0079] It should be noted that in the above general formula (I), when h is 0, the group shown in general formula (I) is divalent, and when h is 2, the group shown in general formula (I) is tetravalent.

[0080] The maleimide group is preferably a group represented by the following general formula (II).

[0081]

[0082] (In the above general formula (II), Ar) 2 (Indicates an aromatic group; dashed lines indicate absence or a single bond; * indicates connection to other atoms.)

[0083] It should be noted that in general formula (II), the dashed line indicates the absence of a single bond or represents a non-existent bond. When the dashed line is absent, the maleimide group in general formula (II) may have a monovalent oxidation state. On the other hand, when the dashed line represents a single bond, the maleimide group in general formula (II) may have a divalent oxidation state.

[0084] The preferred second maleimide compound (A2) in this embodiment is a compound having the structural unit shown in the following general formula (1), or a compound having an aromatic amine compound (a) having one or more alkyl groups (hereinafter also referred to as aromatic amine compound (a)), an aromatic divinyl compound (b1) having two vinyl groups (hereinafter also referred to as aromatic divinyl compound (b1)), and maleic anhydride as reactant (1).

[0085]

[0086] (In the above general formula (1), R) 1 Each can be independently represented as an alkyl group.

[0087] R 2Each of these groups independently represents an alkyl, alkoxy, or alkylthio group having 1 to 10 carbon atoms; an aryl, aryloxy, or arylthio group having 6 to 10 carbon atoms; a cycloalkyl group having 3 to 10 carbon atoms; a halogen atom; a hydroxyl group; or a mercapto group.

[0088] R 3 R 4 R 5 and R 6 Each can independently represent a hydrogen atom or a methyl group, and R 3 and R 4 One side is a hydrogen atom and the other side is a methyl group, R 5 and R 6 One side is a hydrogen atom and the other side is a methyl group.

[0089] X 1 The substituents represented by the following general formula (x) are:

[0090]

[0091] (In the general formula (x), R) 7 and R 8 Each can independently represent a hydrogen atom or a methyl group, and R 7 and R 8 One side is a hydrogen atom and the other side is a methyl group, R 9 Each of these groups independently represents an alkyl, alkoxy, or alkylthio group having 1 to 10 carbon atoms; an aryl, aryloxy, or arylthio group having 6 to 10 carbon atoms; a cycloalkyl group having 3 to 10 carbon atoms; a halogen atom; a hydroxyl group; or a mercapto group, where t represents an integer from 0 to 4.

[0092] r represents the number of connections with X. 1 X of the benzene ring 1 The average of the substitution numbers, where p represents an integer from 1 to 3, q ​​represents an integer from 0 to 4, and k represents an integer from 1 to 100.

[0093] Therefore, during curing, it is possible to achieve a higher level of balance between low moisture absorption and low dielectric loss tangent.

[0094] <Preferred method for the second maleimide compound (A2)>

[0095] The second maleimide compound (A2) of this embodiment preferably has the structural unit shown in the above general formula (1).

[0096] Furthermore, in the above general formula (1), when p is an integer greater than 2, there exist multiple R... 1 They can be the same or different. When q is an integer greater than 2, there exist multiple R... 2They can be the same or different. When t is an integer greater than 2, there exist multiple R... 9 They can be the same or different.

[0097] In the above general formula (1), R 1 Alkyl groups, each individually preferred, represent 1 to 10 carbon atoms; more preferably, they represent 1 to 6 carbon atoms. Furthermore, when p is an integer of 2 or more, multiple R groups are present. 1 They can be the same or different. R is the preferred choice in general formula (1). 1 , which is methyl, ethyl or n-propyl. It should be noted that R in general formula (1) 1 The benzene ring attached can be the benzene ring of an aromatic amine compound (a).

[0098] In the above general formula (1), p preferably represents 1 or 2. It should be noted that R in general formula (1) is preferably... 1 At least one of the 2, 3, 4, 5, or 6 positions of the connected benzene ring is connected with an R 1 .

[0099] In the above general formula (1), R 2 Each of the following is preferably represented independently: an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, or a hydroxyl group; more preferably, an alkyl group having 1 to 10 carbon atoms; and even more preferably, an alkyl group having 1 to 6 carbon atoms. Furthermore, when q is an integer of 2 or more, a plurality of R groups are present. 2 They can be the same or different. R is the preferred choice in general formula (1). 2 , which is methyl, ethyl or n-propyl. It should be noted that R in general formula (1) 2 The connected benzene ring can be the benzene ring of an aromatic divinyl compound (b1). In addition, in the above general formula (1), q preferably represents 0, 1 or 2.

[0100] In the above general formula (1), R 3 and R 4 One side is a hydrogen atom and the other side is a methyl group, R 5 and R 6 One side is a hydrogen atom and the other side is a methyl group. Therefore, the reactivity of the unsaturated bonds inherent in the second maleimide compound (A2) can be maintained at a high level. In the above general formula (1), R... 3 R 4 R 5 and R 6In this compound, if the proportion of alkyl groups increases, the reactivity of the unsaturated bonds inherent in the second maleimide compound (A2) is expected to decrease due to steric hindrance. Therefore, R 3 R 4 R 5 and R 6 If all of them are alkyl groups, the reactivity of the unsaturated bonds in the second maleimide compound (A2) is reduced, and it cannot effectively form a cured product.

[0101] In the above general formula (1), X 1 Represented by the above general formula (x), and in this general formula (x), R 7 Preferably representing a hydrogen atom, R 8 Preferably, it represents a methyl group. Additionally, in the above general formula (x), R... 9 Each of the following is preferably represented independently: an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, or a hydroxyl group; more preferably, an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms; and even more preferably, an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 10 carbon atoms. Furthermore, in the above general formula (x), t preferably represents an integer from 0 to 4, and more preferably an integer from 0 to 3. It should be noted that when t is an integer of 2 or more, multiple R groups exist. 9 They can be the same or different.

[0102] In the above general formula (1), r means that each connection has X 1 X of the benzene ring 1 The average number of substitutions is preferably in the range of 0 to 4, and more preferably in the range of 0 to 3.

[0103] In the above general formula (1), k represents the number of repeating units, preferably an integer from 1 to 100, more preferably an integer from 1 to 90, and even more preferably an integer from 1 to 80.

[0104] The preferred second maleimide compound (A2) in this embodiment is preferably a polymaleimide compound. Furthermore, the number of maleimide groups in this second maleimide compound (A2) is preferably 2 to 20 on average per molecule, more preferably 2 to 15, and even more preferably 2 to 10. By combining the first maleimide compound (A1) as a bismaleimide compound and the second maleimide compound (A2) as a polymaleimide compound having an average of 2 to 10 maleimide groups per molecule, it is preferable from the viewpoint of curability and heat resistance.

[0105] In the curable composition of this embodiment, the content of the second maleimide compound (A2) relative to 100% by mass of the total curable composition is preferably 5% by mass or more and 95% by mass or less, and most preferably 20% by mass or more and 80% by mass or less. When the content of the second maleimide compound (A2) is in the range of 20% by mass or more and 80% by mass or less, it is preferred from the viewpoints of curability and low dielectric loss tangent.

[0106] <Other preferred methods for the second maleimide compound (A2)>

[0107] As another preferred embodiment of the second maleimide compound (A2), it may be a compound in which an aromatic amine compound (a) having one or more alkyl groups, an aromatic divinyl compound (b1) having two vinyl groups, and maleic anhydride are used as reactant (1). In this embodiment, the reactant (1) may further contain an aromatic monovinyl compound (b2) having one vinyl group (hereinafter also referred to as aromatic monovinyl compound (b2)). In addition, the second maleimide compound (A2) of this embodiment is preferably an intermediate amine compound (c) obtained by crosslinking aromatic amine compounds (a) having one or more alkyl groups with each other through an aromatic divinyl compound (b1) having two vinyl groups, and a second maleimide compound (A2) in which maleic anhydride is used as reactant (3). Furthermore, the intermediate amine compound (c) is preferably a compound that uses an aromatic amine compound (a) having one or more alkyl groups but less than three alkyl groups, an aromatic divinyl compound (b1) having two vinyl groups, and an aromatic monovinyl compound (b2) having one vinyl group added as needed as the reaction raw material (2).

[0108] In other words, the intermediate amine compound (c) in this embodiment preferably has the following structure: a structural unit of an aromatic amine compound (a) having an amino group (including substituted amino groups obtained by further substituting the hydrogen atom of the amino group with an alkyl group having 1 to 6 carbon atoms) and one to three alkyl groups on the aromatic ring is chemically bonded to a structural unit of an aromatic divinyl compound (b1) having two vinyl groups, and a structural unit of an aromatic monovinyl compound (b2) is chemically bonded to the aromatic ring in the structural unit of the aromatic amine compound (a) as needed. Furthermore, the second maleimide compound (A2) in this embodiment has a structure in which the amino group (including -NH2 and substituted amino groups) attached to the aromatic ring of the intermediate amine compound (c) is replaced by an N-substituted maleimide ring.

[0109] Therefore, the "second maleimide compound (A2)" in this embodiment and the "intermediate amine compound (c)" which is the precursor of the "second maleimide compound (A2)" are different polymer compounds in that the amino group (including -NH2 and substituted amino groups) attached to the aromatic ring is replaced by an N-substituted maleimide ring.

[0110] It should be noted that the structural unit of the aromatic amine compound (a) mentioned above refers to the group obtained by removing two hydrogen atoms from the aromatic ring of the aromatic amine compound (a). For example, if the aromatic amine compound (a) is as shown in the general formula (a) described later, the group obtained by removing two hydrogen atoms from the benzene ring of the general formula (a) is called the structural unit of the aromatic amine compound (a). Furthermore, the structural unit of the aromatic divinyl compound (b1) mentioned above refers to the group obtained by breaking the unsaturated bonds of the two vinyl groups in the aromatic divinyl compound (b1).

[0111] In this embodiment, an aromatic amine compound (a) having a specific aromatic ring structure is used as the reactant, so the reaction site with the aromatic divinyl compound (b1) described later is easily controlled, and a second maleimide compound (A2) with a uniform chemical structure or chain length is easily obtained. As a result, a second maleimide compound (A2) exhibiting low hygroscopicity and low dielectric loss tangent during curing can be provided.

[0112] Hereinafter, the aromatic amine compound (a) having one or more but less than three alkyl groups, the aromatic divinyl compound (b1) having two vinyl groups, the aromatic monovinyl compound (b2) having one vinyl group (which may be any component), and maleic anhydride, which are constituents of the reaction raw material (1) of the second maleimide compound (A2), will be described, and other preferred embodiments of the second maleimide compound (A2) and the method for manufacturing the second maleimide compound (A2) will be described.

[0113] <<Aromatic Amine Compounds (a)>>

[0114] The aromatic amine compound (a) in this embodiment has an aromatic ring with an amino group (-NH2 or a substituted amino group) attached, and one to three alkyl groups are attached to the aromatic ring. Therefore, the aromatic amine compound (a) can be an amine compound. Furthermore, the aromatic ring forming the central structure of the aromatic amine compound (a) is preferably a monocyclic ring, including an aromatic hydrocarbon ring and an aromatic heterocyclic ring. As an aromatic hydrocarbon ring, a benzene ring is preferred. As an aromatic heterocyclic ring, for example, a hetero-six-membered ring such as a pyran ring or a pyridine ring can be listed. Furthermore, the aromatic amine compound (a) in this embodiment is more preferably an aromatic ring with an unsubstituted amino group (-NH2) attached, and one to three alkyl groups are attached to the aromatic ring.

[0115] In the aromatic amine compound (a) of this embodiment, the alkyl group substituted for one to three hydrogen atoms in the aromatic ring of the aromatic amine compound (a) can be an alkyl group having 1 to 10 carbon atoms, preferably an alkyl group having 1 to 6 carbon atoms, and more preferably an alkyl group having 1 to 3 carbon atoms. The alkyl group can be linear, branched, or cyclic. Examples include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, etc. The smaller the molecular weight of the alkyl group, the more significant the effect (low dimensional change rate) achieved by the present invention. Furthermore, the higher the molecular weight of the alkyl group, the more significant the effect (low water absorption) achieved by the present invention.

[0116] From the viewpoint that the aromatic ring has an amino group (including -NH2 and substituted amino groups) and that the two connecting bonds are suitable for polymerization, the upper limit for the number of alkyl groups attached to the aromatic ring having an amino group (including -NH2 and substituted amino groups) in the aromatic amine compound (a) is simply the number obtained by subtracting 3 from the number of substituted ring constituent atoms in the unsubstituted aromatic ring. For example, if the aromatic ring is a benzene ring, the number of alkyl groups is 3 or less.

[0117] Furthermore, by setting the number of alkyl groups substituted on the aromatic ring of the aromatic amine compound (a) to two or more, the reaction site with the aromatic divinyl compound (b1) described later can be easily controlled, thus easily obtaining a second maleimide compound (A2) with a uniform chemical structure or chain length. As a result, the cured product of the second maleimide compound (A2) readily exhibits low hygroscopicity and excellent high-frequency electrical properties.

[0118] Taking the case where the aromatic ring of the aromatic amine compound (a) in this embodiment is a benzene ring as an example, the preferred mode of the aromatic amine compound (a) will be described.

[0119] In this embodiment, preferably, one or more carbon atoms in the benzene ring constituting the aromatic amine compound (a) that have the largest HOMO electron density (Hückel coefficient) are unsubstituted (or substituted by hydrogen atoms).

[0120] Therefore, it is easy to control the ArS generated by the cationic reagent formed from the aromatic divinyl compound (b1) described later. EReaction and Molecular Design. In more detail, if the carbon atom with the highest HOMO electron density (Hückel coefficient) in the benzene ring constituting the aromatic amine compound (a) is unsubstituted, the carbocation of the aromatic divinyl compound (b1), acting as a cationic reagent, readily reacts with this carbon atom having the highest HOMO electron density. Therefore, by controlling the number and position of alkyl groups attached to the carbon atoms of the benzene ring, the connection sites or number of alkyl groups with the aromatic divinyl compound (b1) can be adjusted. Thus, the chemical structure or molecular chain length of the resulting second maleimide compound (A2) can be easily predicted.

[0121] For example, when the aromatic amine compound (a) has an aniline skeleton having one benzene ring and one amino group, it is preferable that at least one carbon atom at the 2, 4, and 6 positions of the aniline core is substituted with a hydrogen atom. Thus, the cationic reagent formed from the aromatic divinyl compound (b1) described later readily attacks at least one carbon atom at the 2, 4, and 6 positions, which are the meta and para positions with high electron density, of the aniline core. In particular, if an aromatic amine compound (a) having an aniline core substituted with an alkyl group at a specific position is used, the connection site with the aromatic divinyl compound (b1) can be roughly controlled, thus easily yielding a second maleimide compound (A2) with a uniform chemical structure or chain length. For example, if a 2,6-dialkylamine is used as the aromatic amine compound (a), it is considered that a large quantity of a second maleimide compound (A2) connected to the aromatic divinyl compound (b1) at the 4 position is obtained.

[0122] As a specific example of the aromatic amine compound (a) in this embodiment, dimethylaniline (2,3-dimethylaniline, 2,4-dimethylaniline, 2,6-dimethylaniline, 3,4-dimethylaniline or 3,5-dimethylaniline), diethylaniline (2,3-diethylaniline, 2,4-diethylaniline, 2,6-diethylaniline, 3,4-diethylaniline or 3,5-diethylaniline), diisopropylaniline (2,3-diisopropylaniline, 2,4-diisopropylaniline, 2,6-diisopropylaniline, 3,4-diisopropylaniline or 3,5-diethylaniline), ethylmethylaniline (e.g., at the 2,3, 2,4, 2... Ethylmethylaniline (e.g., ethyl methyl aniline with methyl at positions 6, 3, 4, or 3, 5 and ethyl at the other), cyclobutylaniline, cyclopentylaniline, cyclohexylaniline, ortho, meta, or p-toluidine, ortho, meta, or p-ethylaniline, ortho, meta, or p-isopropylaniline, ortho, meta, or p-propylaniline, ortho, meta, or p-butylaniline, methyl isopropylaniline (e.g., methyl isopropylaniline with methyl at positions 2, 3, 2, 4, 2, 6, 3, 4, or 3, 5 and methyl at the other) or ethylbutylaniline (e.g., ethyl butylaniline with ethyl at positions 2, 3, 2, 4, 2, 6, 3, 4, or 3, 5 and butyl at the other), etc. Additionally, the butyl group mentioned above includes n-butyl, tert-butyl, and sec-butyl. It should be noted that the aromatic amine compound (a) in this embodiment can be used alone or in combination of two or more.

[0123] For example, in chemical structures like N-phenylmaleimide, where the maleimide group is directly attached to an unsubstituted benzene ring, the arrangement of the benzene ring and the 5-membered ring of the maleimide in the same plane is stable, making them easy to stack and exhibiting high crystallinity. This results in poor solvent solubility. In contrast, in the cases disclosed herein, such as 2,6-dimethylaniline, where an alkyl group (e.g., methyl) is used as a substituent for the benzene ring, the steric hindrance of the methyl group results in a distorted configuration of the benzene ring and the 5-membered ring of the maleimide, making stacking difficult. This reduces crystallinity and increases solvent solubility, making it a preferred approach. However, if the steric hindrance is too large, there are concerns about hindering the reactivity during the synthesis of maleimide. Therefore, it is preferable to use, for example, an aromatic amine compound having an alkyl group having 1 to 6 carbon atoms (a).

[0124] The aromatic amine compound (a), which is an essential component of the reaction raw material (1) in this embodiment, can be represented by, for example, the following general formula (a).

[0125]

[0126] (In the above general formula (a), R) 1a Indicates alkyl group, p aRepresents integers from 1 to 3. Multiple R exist. 1a They can be the same or different.

[0127] In the above general formula (a), the alkyl group is preferably an alkyl group having 1 to 6 carbon atoms, and more preferably an alkyl group having 1 to 3 carbon atoms. Examples of alkyl groups having 1 to 6 carbon atoms and alkyl groups having 1 to 3 carbon atoms are the same as those described above.

[0128] In the above general formula (a), p a Preferably, it is 1 or 2. It should be noted that R... 1a When multiple alkyl groups are present, they can be the same alkyl group or they can be different alkyl groups.

[0129] It should be noted that in this embodiment, the aromatic amine compound (a) shown in the above general formula (a) can be used alone or in combination of two or more.

[0130] <<Aromatic Divinyl Compounds (b1)>>

[0131] The aromatic divinyl compound (b1) in this embodiment can be used without particular limitation as long as it has two vinyl groups (CH2=CH-) (also called vinyl groups) as substituents on the aromatic ring and can react with the above-mentioned aromatic amine compound (a).

[0132] In addition, in this embodiment, it is preferable that the reaction raw material (1) contains a mixture of aromatic divinyl compound (b1) and aromatic monovinyl compound (b2).

[0133] Examples of aromatic divinyl compounds (b1) include, for example, divinylbenzene, divinylbiphenyl, divinylnaphthalene, and various compounds obtained by substituting one or more alkyl, alkoxy, or alkylthio groups having 1 to 10 carbon atoms; aryl, aryloxy, or arylthio groups having 6 to 10 carbon atoms; cycloalkyl groups having 3 to 10 carbon atoms; halogen atoms; hydroxyl groups; or mercapto groups. A preferred form of this substituent is R in the above general formula (1). 2 The same applies. Furthermore, the aforementioned alkyl group can be either straight-chain or branched. From the viewpoint of exhibiting high heat resistance, the number of carbon atoms in the aforementioned alkyl or alkoxy group is preferably 1 to 4. Specifically, examples of the aforementioned alkyl group include methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, and isobutyl. Examples of the aforementioned alkoxy group include methoxy, ethoxy, propoxy, and butoxy. Examples of the aforementioned halogen atom include fluorine, chlorine, and bromine.

[0134] The aromatic divinyl compound (b1) used as the reaction raw material (1) for the second maleimide compound (A2) of this disclosure is preferably represented by the following formula (b1).

[0135]

[0136] (In the above general formula (b1), R) 2b Each of the following groups independently represents an alkyl, alkoxy, or alkylthio group having 1 to 10 carbon atoms; an aryl, aryloxy, or arylthio group having 6 to 10 carbon atoms; a cycloalkyl group having 3 to 10 carbon atoms; a halogen atom; a hydroxyl group; or a mercapto group, q 1b Represents integers from 0 to 4. It should be noted that q... 1b In the case of integers greater than 2, there exist multiple R. 2b They can be the same or they can be different.

[0137] R in the above formula (b1) 2b It can correspond to R in general formula (1) 2 Therefore, R in the above general formula (b1) 2b Similar to general formula (1), each is preferably represented by an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, or a hydroxyl group, more preferably by an alkyl group having 1 to 10 carbon atoms, and even more preferably by an alkyl group having 1 to 6 carbon atoms.

[0138] In the above general formula (b1), q 1b The preferred value is 0 to 2. It should be noted that q 1b In the case of two or more R, there are multiple R b1 They can be the same group or they can be different groups.

[0139] Specific examples of the aromatic divinyl compound (b1) in this embodiment include, for example, 1,2-divinylbenzene, 1,3-divinylbenzene, 1,4-divinylbenzene, 2,5-dimethyl-1,4-divinylbenzene, 2,5-diethyl-1,4-divinylbenzene, cis,cis,β,β'-diethoxy-m-m-divinylbenzene, 1,4-divinyl-2,5-dibutylbenzene, 1,4-divinyl-2,5-dihexylbenzene, and 1,4-divinyl-2,5-dimethoxy Divinylbenzene compounds, including benzobenzene and compounds derived therefrom; and divinylnaphthalene compounds, including 1,3-divinylnaphthalene, 1,4-divinylnaphthalene, 1,5-divinylnaphthalene, 1,6-divinylnaphthalene, 1,7-divinylnaphthalene, 2,3-divinylnaphthalene, 2,6-divinylnaphthalene, 2,7-divinylnaphthalene, 3,4-divinylnaphthalene, 1,8-divinylnaphthalene, 1,5-dimethoxy-4,8-divinylnaphthalene and compounds derived therefrom, but not limited to these.

[0140] It should be noted that the aromatic divinyl compound (b1) in this embodiment can be used alone or in combination of two or more.

[0141] In particular, from a flowability viewpoint, divinylbenzene and compounds having substituents on their aromatic rings are preferred as aromatic divinyl compounds (b1), with divinylbenzene being more preferred. Furthermore, in this embodiment, the substitution position of the vinyl group in divinylbenzene is not particularly limited, but a meta-form is preferred as the main component. The content of the meta-form in divinylbenzene is preferably 40% by mass or more, more preferably 50% by mass or more, relative to the total amount of divinylbenzene.

[0142] In this embodiment, the structural unit of the aromatic divinyl compound (b1) preferably contains 10 to 90% by mass relative to the total amount (100% by mass) of the second maleimide compound (A2), more preferably 20 to 90% by mass. The structural unit of the aromatic divinyl compound (b1) refers to a group obtained by removing two hydrogen atoms (a total of four hydrogen atoms) from each of the two vinyl groups of the aromatic divinyl compound (b1).

[0143] <<Aromatic Monovinyl Compounds (b2)>>

[0144] In this embodiment, the second maleimide compound (A2) may further utilize other compounds as reactants besides the aromatic amine compound (a), the aromatic divinyl compound (b1), and maleic anhydride. Examples of such other compounds include, for instance, an aromatic monovinyl compound (b2) having one vinyl group. Specifically, in this embodiment, it is preferable to use the aromatic amine compound (a), the aromatic divinyl compound (b1), the aromatic monovinyl compound (b2), and maleic anhydride as reactants (1). In this embodiment, the second maleimide compound (A2) uses an aromatic monovinyl compound (b2) as a reactant in addition to the aromatic amine compound (a), the aromatic divinyl compound (b1), and maleic anhydride, resulting in a cured second maleimide compound (A2) that exhibits excellent low dielectric loss tangent, and is therefore preferred.

[0145] In addition, aromatic monovinyl compounds (b2) also generate carbocations in the same way as aromatic divinyl compounds (b1), and therefore readily react with the carbon atoms in the aromatic hydrocarbon rings that constitute aromatic amine compounds (a) that have the highest HOMO electron density (Hückel coefficient).

[0146] The aromatic monovinyl compound (b2) in this embodiment can be exemplified by vinylbenzene (styrene), vinylbiphenyl, vinylnaphthalene, and various compounds obtained by substituting one or more alkyl, alkoxy, or alkylthio groups having 1 to 10 carbon atoms, aryl, aryloxy, or arylthio groups having 6 to 10 carbon atoms, cycloalkyl groups having 3 to 10 carbon atoms, halogen atoms, hydroxyl groups, or mercapto groups, etc. The alkyl group can be either straight-chain or branched, and can have unsaturated bonds in its structure. Where low hygroscopicity is important, the alkyl group or alkoxy group is preferably 1 to 4 carbon atoms. Specifically, examples of the alkyl group include methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, isobutyl, etc. Examples of the alkoxy group include methoxy, ethoxy, propoxy, butoxy, etc. Examples of the halogen atom include fluorine, chlorine, bromine, etc.

[0147] The aromatic monovinyl compound (b2) that can serve as the reaction raw material (1) for the second maleimide compound (A2) of this disclosure can be represented by the following general formula (b2).

[0148]

[0149] (In the above general formula (b2), R) 9b Each of the following can independently represent an alkyl, alkoxy, or alkylthio group having 1 to 10 carbon atoms; an aryl, aryloxy, or arylthio group having 6 to 10 carbon atoms; a cycloalkyl group having 3 to 10 carbon atoms; a halogen atom; a hydroxyl group; or a mercapto group. 1b Represents integers from 0 to 5. It should be noted that t... 1b In the case of integers greater than 2, there exist multiple R. 9b They can be the same or they can be different.

[0150] R in the above formula (b2) 9b It can correspond to R in the general formula (x) 9 Therefore, R in the above general formula (b1) 9b Similar to general formula (x), each is preferably represented independently as an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, or a hydroxyl group, more preferably as an alkyl group having 1 to 10 carbon atoms, and even more preferably as an alkyl group having 1 to 6 carbon atoms.

[0151] In the above general formula (b1), t 1b The preferred value is 1 to 4. It should be noted that t 1b In the case of two or more R, there are multiple R 9b They can be the same group or they can be different groups.

[0152] Specific examples of aromatic monovinyl compounds (b2) in this embodiment include, for example, vinylbenzene compounds such as styrene, fluorostyrene, vinylbenzyl chloride, alkylvinylbenzene (o-, m-, p-methylstyrene; o-, m-, p-ethylvinylbenzene), o-, m-, p-(chloromethyl)styrene and compounds composed of their derivatives; biphenyl compounds such as 4-vinylbiphenyl, 4-vinyl-p-terphenyl and compounds composed of their derivatives; and vinylnaphthalene compounds such as 1-vinylnaphthalene, 2-vinylnaphthalene and compounds composed of their derivatives, but are not limited to these.

[0153] In particular, from the viewpoint of obtaining raw materials, alkyl vinylbenzenes and compounds having substituents on their aromatic rings are preferred, and ethyl vinylbenzenes are more preferred.

[0154] Furthermore, the substitution positions of vinyl and ethyl groups in ethyl vinylbenzene are not particularly limited, but the meta group is preferred as the main component. The content of the meta group in ethyl vinylbenzene is more preferably 40% by mass or more relative to the total amount of ethyl vinylbenzene, and even more preferably 50% by mass or more.

[0155] When using an aromatic monovinyl compound (b2) as the reaction raw material (1) of the second maleimide compound (A2) in this embodiment, the molar ratio ((b1) / (b2)) of the aromatic monovinyl compound (b2) to the aromatic divinyl compound (b1) in the above-mentioned reaction raw material (1) is preferably 99 / 1 to 50 / 50, more preferably 98 / 2 to 70 / 30.

[0156] In this embodiment, relative to the total amount (100% by mass) of the second maleimide compound (A2), the structural unit of the aromatic monovinyl compound (b2) preferably contains 0 to 40% by mass, more preferably 0 to 30% by mass. The structural unit of the aromatic monovinyl compound (b2) refers to a group obtained by removing two hydrogen atoms from one vinyl group of the aromatic monovinyl compound (b2).

[0157] <<Malic anhydride>>

[0158] In this embodiment, maleic anhydride is an essential component of the reaction raw material (1) of the second maleimide compound (A2), as described later in the section on the method of manufacturing the second maleimide compound (A2), and is used for the maleimization of the amino group (including -NH2 and substituted amino groups) from the aromatic amine compound (a).

[0159] <Preferred method for the second maleimide compound (A2)>

[0160] Hereinafter, the preferred second maleimide compound (A2) of this disclosure will be described using the case where each aromatic ring is a benzene ring as an example. The following chemical structural formulas are used to illustrate this disclosure, and the scope of this disclosure is not limited to the following chemical structural formulas.

[0161] In this embodiment, the second maleimide compound (A2) is preferably represented by the following general formula (2).

[0162]

[0163] (In the above general formula (2), R) 1 Each independently represents an alkyl group, R 2 Each of the following independently represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, or a hydroxyl group; R 3 R 4 R 5 and R 6 Each can independently represent a hydrogen atom or a methyl group, and R 3 and R 4 One side is a hydrogen atom and the other side is a methyl group, R 5 and R 6 One side is a hydrogen atom and the other side is a methyl group.

[0164] X 1 The substituents represented by the following general formula (x) are:

[0165]

[0166] (In the general formula (x), R) 7 and R 8 Each can independently represent a hydrogen atom or a methyl group, and R 7 and R 8 One side is a hydrogen atom and the other side is a methyl group, R 9 (This indicates an alkyl group with 1 to 10 carbon atoms, an alkoxy group with 1 to 10 carbon atoms, an aryl group with 6 to 10 carbon atoms, a cycloalkyl group with 3 to 10 carbon atoms, a halogen atom, or a hydroxyl group; t represents an integer from 0 to 4.)

[0167] M 21 M represents a hydrogen atom or a group represented by the following general formula (i). 22 Represents a hydrogen atom, a group represented by general formula (ii) below, or a group represented by general formula (iii) below.

[0168]

[0169] In the above general formula (i), R 9R represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, or a hydroxyl group. 7 and R 8 Each can independently represent a hydrogen atom or a methyl group, and R 7 and R 8 One side is a hydrogen atom and the other side is a methyl group, t represents an integer from 0 to 4, and * indicates a bond with other atoms. It should be noted that when t is an integer greater than 2, multiple R groups exist. 9 They can be the same or different.

[0170]

[0171] In the above general formula (ii), R 1ii Indicates alkyl group, p ii Represents integers from 0 to 4. It should be noted that p... ii In the case of integers greater than 2, there exist multiple R. 1ii They can be the same or different. In the above general formula (iii), R 1iii R represents an alkyl group. 9 R represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, or a hydroxyl group. 7 and R 8 Each can independently represent a hydrogen atom or a methyl group, and R 7 and R 8 One side is a hydrogen atom and the other side is a methyl group, p iii t represents integers from 0 to 3, r represents integers from 0 to 4, and r represents integers from 0 to 4. 1iii For each connection there is X 1 The average number of substitutions on the benzene ring, representing numbers from 1 to 4, with * indicating bonds to other atoms. It should be noted that p... iii In the case of integers greater than 2, there exist multiple R. 1iii They can be the same or different. When t is an integer greater than 2, there exist multiple R. 9 They can be the same or different.

[0172] r represents the number of connections with X. 1 X of the benzene ring 1 The average of the substitution numbers, where p represents an integer from 1 to 3, q ​​represents an integer from 0 to 4, and k represents an integer from 1 to 100.

[0173] In the above general formula (2), when p is an integer greater than 2, there exist multiple R... 1They can be the same or different. When q is an integer greater than 2, there exist multiple R. 2 They can be the same or different. When t is an integer greater than 2, there exist multiple R. 9 They can be the same or different.

[0174] It should be noted that R in the above general formula (2) 1 ~R 9 X 1 The preferred methods for p, q, r, t, and k are the same as those in the general formula (1) above. Furthermore, the general formula (i) above corresponds to the general formula (x) above, and R in the general formula (ii) above... 1ii R corresponds to the above general formula (1) 1 R in the above general formula (iii) 1iii R corresponds to the above general formula (1) 1 .

[0175] The number-average molecular weight (Mn) of the second maleimide compound (A2) disclosed herein is preferably in the range of 350 to 2,000, more preferably in the range of 400 to 1,500. Furthermore, the weight-average molecular weight (Mw) of the second maleimide compound (A2) is preferably in the range of 400 to 500,000, more preferably in the range of 450 to 400,000.

[0176] For the second maleimide compound (A2) of this disclosure, considering its excellent low dielectric constant and low dielectric loss tangent, the molecular weight distribution (weight-average molecular weight (Mw) / number-average molecular weight (Mn)) calculated by gel permeation chromatography (GPC) is preferably in the range of 1.001 to 500, more preferably 1.001 to 400. It should be noted that, according to the GPC chromatogram obtained by GPC, when the molecular weight distribution spans a wide range and contains a high proportion of high molecular weight components, the proportion of high molecular weight components that contribute to flexibility increases. Therefore, compared with conventional cured products using maleimide, brittleness is suppressed, and a cured product with excellent flexibility and suppleness can be obtained, which is a preferred method.

[0177] It should be noted that the number-average molecular weight (Mn), weight-average molecular weight (Mw), and molecular weight distribution (weight-average molecular weight (Mw) / number-average molecular weight (Mn)) of the second maleimide compound (A2) in this embodiment were determined by gel permeation chromatography (hereinafter referred to as "GPC") under the determination conditions described in the examples below.

[0178] In this embodiment, when the second maleimide compound (A2) contains an indane skeleton (or a structural unit having an indane skeleton) as shown in the following general formula (3), the ratio of the indane skeleton relative to the total amount (100% by mass) of the second maleimide compound (A2) is preferably 10% by mass or less, preferably 5% by mass or less, more preferably 3% by mass or less, even more preferably 2% by mass or less, and particularly preferably 0.9% by mass or less.

[0179]

[0180] (In the above general formula (3), R) 31 R 32 and R 33 R represents either a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, respectively. 34 Each of the following groups independently represents an alkyl, alkoxy, or alkylthio group having 1 to 10 carbon atoms; an aryl, aryloxy, or arylthio group having 6 to 10 carbon atoms; a cycloalkyl group having 3 to 10 carbon atoms; a halogen atom; a hydroxyl group; or a mercapto group, q 3 q represents an integer from 0 to 3. 3 In the case of integers greater than 2, there exist multiple R. 34 They can be the same or different. Also, * indicates a connection to other atoms.

[0181] In the above general formula (3), R 34 Preferably, each alkyl group independently represents 1 to 6 carbon atoms, and more preferably, it represents 1 to 3 carbon atoms. Furthermore, in the above general formula (3), R... 31 R 32 and R 33 Preferably, it contains hydrogen atoms or methyl groups.

[0182] <Method for manufacturing the second maleimide compound (A2)>

[0183] The following describes the method for manufacturing the second maleimide compound (A2) disclosed herein.

[0184] The preparation method of the second maleimide compound (A2) in this embodiment is not particularly limited, as long as an aromatic amine compound (a), an aromatic divinyl compound (b1), and maleic anhydride are used as reactants (1), or the compound is prepared in a manner having the structural unit shown in the above general formula (1). As an example of the preparation method of the second maleimide compound (A2) disclosed herein, a preparation method including the following steps (1) and (2) can be listed.

[0185] Step (1): The step of reacting an aromatic amine compound (a) with an aromatic divinyl compound (b1) as a reaction raw material (2) to obtain the intermediate amine compound (c) in this embodiment;

[0186] Step (2): The process of reacting the intermediate amine compound (c) obtained in step (1) with maleic anhydride as a reaction raw material (3) to obtain the second maleimide compound (A2) disclosed herein.

[0187] Specifically, the method for producing the second maleimide compound (A2) in this embodiment preferably includes a step (1) (also called a crosslinking step) in which an aromatic amine compound (a) and an aromatic divinyl compound (b1) are reacted under a solid acid catalyst, and a step (2) (also called a condensation step) in which the intermediate amine compound (c) generated by the above step (1) is condensed with maleic anhydride.

[0188] The following describes each step of the method for manufacturing the second maleimide compound (A2) disclosed herein.

[0189] <<Process (1): Manufacturing process of intermediate amine compound (c)>>

[0190] The manufacturing process of the intermediate amine compound (c) in this embodiment will be described below.

[0191] Step (1) in this embodiment is not particularly limited, and may be a step of reacting the above-mentioned aromatic amine compound (a), the above-mentioned aromatic divinyl compound (b1) (e.g., divinylbenzene), and further, as needed, other compounds such as aromatic monovinyl compound (b2) (e.g., ethylvinylbenzene) in the presence of an acid catalyst. This produces an intermediate amine compound (c).

[0192] As for the mixing ratio of the aromatic amine compound (a) and the aromatic divinyl compound (b1), considering the balance of formability and curability during the manufacture of the resulting cured product, the molar ratio of the aromatic divinyl compound (b1) to 1 mole of the aromatic amine compound (a) is preferably 0.1 to 10 moles, more preferably 0.2 to 3 moles. Furthermore, when using the aromatic monovinyl compound (b2), the molar ratio of the total of the aromatic divinyl compound (b1) and the aromatic monovinyl compound (b2) to 1 mole of the aromatic amine compound (a) is preferably 0.1 to 10 moles, more preferably 0.2 to 3 moles.

[0193] Furthermore, as a specific method for carrying out the above reaction, all the raw materials are usually loaded together and reacted directly at a predetermined temperature; or an aromatic amine compound (a) and an acid catalyst are loaded, and while maintaining the predetermined temperature, an aromatic divinyl compound (b1), other compounds (e.g., an aromatic monovinyl compound (b2)), etc., are added dropwise while the reaction is carried out. In this case, the dropwise addition time is usually 0.1 to 12 hours, preferably 6 hours or less. After the reaction, if a solvent is used, the solvent and unreacted substances are removed by distillation as needed to obtain the above-mentioned intermediate amine compound (c); if no solvent is used, the unreacted substances are removed by distillation, thereby obtaining the above-mentioned intermediate amine compound (c) as the target substance.

[0194] For the acid catalyst used in step (1) of this embodiment, examples include inorganic acids such as phosphoric acid, hydrochloric acid, and sulfuric acid, organic acids such as oxalic acid, benzenesulfonic acid, toluenesulfonic acid, methanesulfonic acid, and fluoromethanesulfonic acid, as well as solid acids such as activated clay, acid clay, silica-alumina, zeolite, strong acid ion exchange resin, and heteropolyhydrochloric acid. From the viewpoint of processability, it is preferable to use a solid acid that can be easily removed by filtration after the reaction. When using other acids, it is preferable to perform base-based neutralization and water-based washing after the reaction.

[0195] Regarding the amount of the acid catalyst, relative to 100 parts by mass of the total amount of added raw materials (aromatic divinyl compound (b1) or a mixture of aromatic divinyl compound (b1) and aromatic monovinyl compound (b2), and aromatic amine compound (a)), the acid catalyst is prepared in the range of 1 to 100 parts by mass. Considering processability and economy, 1 to 60 parts by mass is preferred. The reaction temperature is generally in the range of 100 to 270°C, and is preferably 100 to 220°C to suppress the formation of isomer structures and avoid side reactions such as thermal decomposition.

[0196] In step (1) of this embodiment, the reaction time of the aromatic divinyl compound (b1) or the mixture of aromatic divinyl compound (b1) and aromatic monovinyl compound (b2) and the mixture of aromatic amine compound (a), i.e. the crosslinking reaction time, is such that the reaction will not proceed completely if the time is short, and side reactions such as thermal decomposition of the product will occur if the time is long. Therefore, under the above reaction temperature conditions, the reaction time is usually in the range of 1 to 48 hours, and preferably in the range of 1 to 30 hours.

[0197] In the method for producing the intermediate amine compound (c) in this embodiment, aniline or its derivatives also serve as solvents, so other solvents are not necessary, but solvents may also be used. For example, when the reaction is carried out using divinylbenzene as a raw material, the following method can be used: using a solvent that can azeotropically dehydrate, such as toluene, xylene, or chlorobenzene, the water contained in the catalyst, etc., is azeotropically dehydrated as needed, the solvent is removed by distillation, and then the reaction is carried out within the above-mentioned reaction temperature range.

[0198] The intermediate amine compound (c) obtained by the above process (1) preferably has structural units represented by the following general formula (4).

[0199]

[0200] (In the above general formula (4), R) 1 Each independently represents an alkyl group, R 2 Each of these groups independently represents an alkyl, alkoxy, or alkylthio group having 1 to 10 carbon atoms; an aryl, aryloxy, or arylthio group having 6 to 10 carbon atoms; a cycloalkyl group having 3 to 10 carbon atoms; a halogen atom; or a hydroxyl or mercapto group.

[0201] R 3 R 4 R 5 and R 6 Each can independently represent a hydrogen atom or a methyl group, and R 3 and R 4 One side is a hydrogen atom and the other side is a methyl group, R 5 and R 6 One side is a hydrogen atom and the other side is a methyl group.

[0202] X 1 The substituents represented by the following general formula (x) are:

[0203]

[0204] (In the general formula (x), R) 7 and R 8 Each can independently represent a hydrogen atom or a methyl group, and R 7 and R 8 One side is a hydrogen atom and the other side is a methyl group, R 9 (This indicates an alkyl group, and t represents an integer from 0 to 4.)

[0205] r represents the number of connections with X. 1 X of the benzene ring 1 The average of the substitution numbers, where p represents an integer from 1 to 3, q ​​represents an integer from 0 to 4, and k represents an integer from 1 to 100.

[0206] Furthermore, in the above general formula (4), when p is an integer greater than 2, there exist multiple R... 1 They can be the same or different. When q is an integer greater than 2, there exist multiple R... 2 They can be the same or different. When t is an integer greater than 2, there exist multiple R... 9 They can be the same or different.

[0207] It should be noted that R in the above general formula (4) 1 ~R 9 X 1 The preferred forms of p, q, r, t, and k are the same as those in the general formula (1) above. Additionally, as another preferred form of the intermediate amine compound (c) obtained through the above step (1), the structure in the general formula (2) above, in which the N-substituted maleimide group is substituted with an amino group (including -NH2 and substituted amino groups), is also listed as a preferred form of the second maleimide compound (A2).

[0208] In this embodiment, the amine equivalent of the intermediate amine compound (c) is preferably 172 to 400 g / equivalent, and more preferably 172 to 350 g / equivalent.

[0209] It should be noted that the determination of the amine equivalent of the intermediate amine compound (c) in this specification is set as the value determined by the neutralization titration method specified in JISK 0070 (1992).

[0210] <<Process (2): Maleimide>>

[0211] In this embodiment, step (2) is a step of reacting the intermediate amine compound (c) obtained in step (1) with maleic anhydride. By performing a maleimide reaction on the amino group (including -NH2 and substituted amino groups) of the intermediate amine compound (c), a chemical structure in which the above-mentioned amino group is substituted by an N-substituted maleimide ring can be formed, thus obtaining the second maleimide compound (A2) of this disclosure.

[0212] In this embodiment, the intermediate amine compound (c) of the above general formula (4) obtained by step (1) is loaded into a reactor, dissolved in a suitable solvent, and then reacted with maleic anhydride in the presence of a catalyst. After the reaction, unreacted maleic anhydride or other impurities are removed by washing with water, and the solvent is removed by depressurization, thereby obtaining the second maleimide compound (A2) as the target. In addition, a dehydrating agent may be used during the reaction as needed.

[0213] Organic solvents that can be used in step (2) of this embodiment include ketones such as acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, cyclohexanone, and acetophenone; nonprotic solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone, acetonitrile, and sulfolane; cyclic ethers such as dioxane and tetrahydrofuran; esters such as ethyl acetate and butyl acetate; and aromatic solvents such as benzene, toluene, and xylene. They can be used alone or in combination.

[0214] In step (2) of this embodiment, the preferred method is to mix the intermediate amine compound (c) and maleic anhydride in a ratio of maleic anhydride to the amino equivalent of intermediate amine compound (c) in the range of 1 to 5, more preferably in a ratio of 1 to 3, and react them in an organic solvent in a mass ratio of 0.1 to 10, preferably 0.2 to 5, relative to the total amount of intermediate amine compound (c) and maleic anhydride.

[0215] As catalysts that can be used in step (2) of this embodiment, examples include inorganic salts such as acetates, chlorides, bromides, sulfates, and nitrates of nickel, cobalt, sodium, calcium, iron, lithium, and manganese; inorganic acids such as phosphoric acid, hydrochloric acid, and sulfuric acid; organic acids such as oxalic acid, benzenesulfonic acid, toluenesulfonic acid, methanesulfonic acid, and fluoromethanesulfonic acid; solid acids such as activated clay, acid clay, silica-alumina, zeolite, and strongly acidic ion exchange resin; heteropolyhydrochloric acid, etc., with toluenesulfonic acid being particularly preferred.

[0216] As a dehydrating agent used in step (2) of this embodiment, examples include lower aliphatic carboxylic anhydrides such as acetic anhydride, propionic anhydride, and butyric anhydride; oxides such as phosphorus pentoxide, calcium oxide, and barium oxide; inorganic acids such as sulfuric acid; and porous ceramics such as molecular sieves. Acetic anhydride is preferred.

[0217] In step (2) of this embodiment, there are no particular restrictions on the amount of catalyst and dehydrating agent that can be used. Generally, relative to the amino (-NH2)1 equivalent of the intermediate amine compound (c), the catalyst can be used in amounts of 0.0001 to 1.0 moles, preferably 0.01 to 0.3 moles, and the dehydrating agent can be used in amounts of 1 to 3 moles, preferably 1 to 1.5 moles.

[0218] In step (2) of this embodiment, as the reaction conditions for maleimide formation, the above-mentioned intermediate amine compound (c) and maleic anhydride are loaded and reacted at a temperature range of 10 to 100°C, preferably 30 to 60°C, for 0.5 to 12 hours, preferably 1 to 4 hours. Then, the above-mentioned catalyst is added and reacted at a temperature range of 90 to 130°C, preferably 105 to 120°C, for 1 to 24 hours, preferably 1 to 10 hours.

[0219] (Curing agent (B))

[0220] In the curing composition of this embodiment, a curing agent (B) may also be added within a range that does not impair the curing properties of the present invention. It should be noted that, relative to 100% by mass of the total curing composition, the curing agent (B) is preferably 2% by mass or more and 20% by mass or less, and most preferably 5% by mass or more and 10% by mass or less. A curing agent (B) content in the range of 5% by mass or more and 10% by mass or less is preferred from the viewpoint of low dielectric loss tangent.

[0221] Examples of curing agents (B) used in this embodiment include amine compounds, cyanate ester compounds, amide compounds, acid anhydride compounds, phenol compounds, polyphenylene ether compounds, compounds having substituents containing unsaturated double bonds, diene polymers, etc. These curing agents can be used alone or in combination of two or more.

[0222] Examples of the aforementioned amine compounds include diaminodiphenylmethane, diethylenetriamine, triethylenetetramine, diaminodiphenyl sulfone, isophorone diamine, imidazole, BF3-amine complexes, and guanidine derivatives.

[0223] Examples of the aforementioned cyanate compounds include, for example, bisphenol A type cyanate resin, bisphenol F type cyanate resin, bisphenol E type cyanate resin, bisphenol S type cyanate resin, bisphenol sulfide type cyanate resin, phenyl ether type cyanate resin, naphthyl ether type cyanate resin, biphenyl type cyanate resin, tetramethylbiphenyl type cyanate resin, polyhydroxynaphthalene type cyanate resin, phenol phenolic varnish type cyanate resin, cresol phenolic varnish type cyanate resin, triphenylmethane type cyanate resin, tetraphenylethane type cyanate resin, dicyclopentadiene-phenol addition reaction type cyanate resin, phenol aralkyl type cyanate resin, naphthol phenolic cyanate resin, naphthol aralkyl type cyanate resin, naphthol-phenol cocondensed phenolic cyanate resin, naphthol-cresol cocondensed phenolic cyanate resin, aromatic hydrocarbon formaldehyde resin modified phenol resin type cyanate resin, biphenyl modified phenolic cyanate resin, anthracene type cyanate resin, etc. They can be used individually or in combination of two or more.

[0224] Examples of the aforementioned amide compounds include dicyandiamide and polyamide resins synthesized from dimers of linolenic acid and ethylenediamine.

[0225] Examples of the aforementioned anhydride compounds include phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, hexahydrophthalic anhydride, and methylhexahydrophthalic anhydride.

[0226] Examples of the aforementioned phenolic compounds include phenolic varnish resins, cresol phenolic varnish resins, aromatic hydrocarbon formaldehyde resin-modified phenolic resins, dicyclopentadiene phenol addition-type resins, phenol aralkyl resins (Zyloc resins), polyvalent phenolic varnish resins synthesized from polyvalent hydroxyl compounds represented by resorcinol phenolic varnish resins and formaldehyde, naphthol aralkyl resins, trimethylolpropane resins, tetraphenol ethane resins, naphthol phenolic varnish resins, and naphthol-phenol cocondensed phenolic varnish resins. Naphthol-cresol cocondensed phenolic varnish resin, biphenyl-modified phenol resin (a polyvalent phenol compound with a phenol core linked by dimethylene groups), biphenyl-modified naphthol resin (a polyvalent naphthol compound with a phenol core linked by dimethylene groups), aminotriazine-modified phenol resin (a polyvalent phenol compound with a phenol core linked by melamine, benzoguanamine, etc.), and alkoxy-containing aromatic ring-modified phenolic varnish resin (a polyvalent phenol compound with a phenol core and an alkoxy-containing aromatic ring linked by formaldehyde), etc., are all polyvalent phenol compounds.

[0227] As the above-mentioned polyphenylene ether compounds, it is preferred, for example, to have the structure shown in the following general formula (5) or (6).

[0228]

[0229] In the above general formulas (5) and (6), R d1 ~R d8 Examples of structures that can be independently listed include hydrogen atoms, alkyl groups with 1 to 5 carbon atoms, alkenyl groups with 1 to 5 carbon atoms, cycloalkyl groups with 3 to 5 carbon atoms, alkoxy groups with 1 to 5 carbon atoms, thioether groups with 1 to 5 carbon atoms, alkyl carbonyl groups with 2 to 5 carbon atoms, alkoxy carbonyl groups with 2 to 5 carbon atoms, alkyl carbonyloxy groups with 2 to 5 carbon atoms, and alkyl sulfonyl groups with 1 to 5 carbon atoms. As terminal structures of the structures in the above general formulas (5) and (6), structures having groups containing hydroxyl groups or reactive double bonds can be listed. Furthermore, v is an integer value from 1 to 30, and w and u are also integer values ​​from 1 to 30.

[0230] There are no particular limitations on the thioether groups with 1 to 5 carbon atoms mentioned above, and examples include methyl thio, ethyl thio, propyl thio, isopropyl thio, butyl thio, pentyl thio, etc.

[0231] There are no particular limitations on the alkyl carbonyl groups with 2 to 5 carbon atoms mentioned above, and examples include methyl carbonyl, ethyl carbonyl, propyl carbonyl, isopropyl carbonyl, butyl carbonyl, etc.

[0232] There are no particular limitations on the alkoxycarbonyl groups with 2 to 5 carbon atoms mentioned above, and examples include methyloxycarbonyl, ethyloxycarbonyl, propyloxycarbonyl, isopropyloxycarbonyl, butyloxycarbonyl, etc.

[0233] There are no particular limitations on the alkyl carbonyloxy groups with 2 to 5 carbon atoms mentioned above, and examples include methyl carbonyloxy, ethyl carbonyloxy, propyl carbonyloxy, isopropyl carbonyloxy, butyl carbonyloxy, etc.

[0234] There are no particular limitations on the alkyl sulfonyl groups with 1 to 5 carbon atoms mentioned above, and examples include methyl sulfonyl, ethyl sulfonyl, propyl sulfonyl, isopropyl sulfonyl, butyl sulfonyl, pentyl sulfonyl, etc.

[0235] In this embodiment, R in the above general formulas (5) and (6) d1 ~R d8 They may be the same or different from each other, preferably hydrogen atoms, alkyl groups having 1 to 5 carbon atoms, or cycloalkyl groups having 3 to 5 carbon atoms, more preferably hydrogen atoms or alkyl groups having 1 to 5 carbon atoms, even more preferably hydrogen atoms, methyl, or ethyl, and particularly preferably hydrogen atoms or methyl.

[0236] The Y in the above general formula (6) can be listed as a divalent aromatic group from aromatic compounds having two phenolic hydroxyl groups.

[0237] Furthermore, there are no particular limitations on the aromatic compounds having two phenolic hydroxyl groups mentioned above, and examples include catechol, resorcinol, hydroquinone, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 4,4'-biphenol, bisphenol A, bisphenol B, bisphenol BP, bisphenol C, bisphenol F, and tetramethylbisphenol A. Among these, hydroquinone, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 4,4'-biphenol, bisphenol A, bisphenol E, and bisphenol F are preferred, and 4,4'-biphenol, bisphenol A, and tetramethylbisphenol A are more preferred.

[0238] Furthermore, in the aforementioned aromatic compound with two phenolic hydroxyl groups, the two phenolic hydroxyl groups form a phenyl ether bond (the two oxygen atoms connected to Y), thus Y becomes a divalent aromatic group from the aromatic compound with two phenolic hydroxyl groups. In other words, the group obtained by removing any two hydrogen atoms from the aforementioned aromatic compound with two phenolic hydroxyl groups is considered as "a divalent aromatic group from the aromatic compound with two phenolic hydroxyl groups".

[0239] As for compounds having the above-mentioned substituents containing unsaturated double bonds, there is no particular limitation as long as the molecule has two or more substituents containing unsaturated bonds. Examples of substituents containing unsaturated bonds include allyl, isopropenyl, 1-propenyl, acryloyl, methacryloyl, styryl, styrylmethyl, etc.

[0240] Examples of diene polymers mentioned above include unmodified diene polymers that have not been modified by polar groups. Here, polar groups are functional groups that affect dielectric properties; examples include phenolic groups, amino groups, and epoxy groups. There are no particular limitations on the diene polymers mentioned above; for example, 1,2-polybutadiene and 1,4-polybutadiene can be used.

[0241] As the diene-based polymers mentioned above, homopolymers of butadiene in which more than 50% of the butadiene units in the polymer chain are 1,2-bonded and their derivatives can also be used.

[0242] (Other resins (C))

[0243] Furthermore, other resins (C) may be included in addition to the first maleimide compound (A1) and the second maleimide compound (A2), provided that this does not impair the purpose of this disclosure. These other resins (C) may be suitable as bismaleimides, allyl ether compounds, allyl amine compounds, triallyl cyanurate, alkenylphenol compounds, vinyl-containing polyolefin compounds, epoxy resins, phenolic resins, reactive ester resins, polyphenylene ether resins, benzoxazine resins, styrene-maleic anhydride copolymers, polybutadiene and its modified forms, polyacetal resins, polyvinyl alcohol resins, liquid crystal polymers, fluoropolymers, polystyrene, polyethylene, polyimide resins, thermosetting polyimide resins, silicone, silicone oil, etc.

[0244] The content of other resins (C) relative to 100% by mass of the total curable composition is preferably 2% by mass or more and 20% by mass or less, and most preferably 5% by mass or more and 10% by mass or less. When the content of other resins (C) is in the range of 5% by mass or more and 10% by mass or less, it is preferred from the viewpoint of heat resistance and compatibility.

[0245] (Curing accelerator)

[0246] The curing composition of this embodiment can also be appropriately combined with a curing accelerator as needed. Various substances can be used as the curing accelerator; for example, adding polymerization initiators such as organic peroxides and azo compounds, or basic catalysts such as phosphine compounds and tertiary amines is effective. Specific examples of the curing accelerator include benzoyl peroxide, dicumyl peroxide, azobisisobutyronitrile, triphenylphosphine, TPP-MK, TPP-K, triethylamine, imidazoles, etc. The curing accelerator can be used alone or in combination with two or more. The preferred amount of the curing accelerator in this embodiment is 0.05% to 5% by mass of the total curing resin composition.

[0247] (additive)

[0248] The curable composition of this embodiment may also be appropriately combined with additives as needed. Examples of such additives include silane coupling agents, release agents, pigments, emulsifiers, non-halogenated flame retardants, inorganic fillers, flame retardants, and solvents. The content of additives is preferably 1% to 20% by mass relative to 100% of the total weight of the curable composition, and most preferably 3% to 10% by mass.

[0249] Examples of flame retardants include inorganic phosphorus-based flame retardants, organophosphorus-based flame retardants, halogen-based flame retardants, and non-halogen-based flame retardants. In the curable composition of this embodiment, to achieve flame retardancy without compromising the intended purpose, it is more preferable to incorporate a non-halogen-based flame retardant that substantially does not contain halogen atoms. Examples of such non-halogen-based flame retardants include phosphorus-based flame retardants, nitrogen-based flame retardants, organosilicon-based flame retardants, inorganic flame retardants, and organometallic salt-based flame retardants, which can be used alone or in combination.

[0250] In the curable composition of this embodiment, inorganic fillers can be added as needed. Examples of such inorganic fillers include fused silica, crystalline silica, alumina, silicon nitride, and aluminum hydroxide. When the amount of the inorganic filler is particularly increased, fused silica is preferred. The fused silica can be either crushed or spherical; to increase the amount of fused silica and suppress the increase in the melt viscosity of the molding material, spherical fused silica is preferred. Furthermore, to increase the amount of spherical silica, the particle size distribution of the spherical silica is appropriately adjusted. Regarding its filling rate, considering flame retardancy, a high rate is preferred, particularly 30% by mass or more and 50% by mass or less relative to the total amount of the curable composition. Additionally, when the above-mentioned curable composition is used for applications such as conductive pastes detailed below, conductive fillers such as silver powder and copper powder can be used.

[0251] In the curable composition of this embodiment, the lower limit of the total content of the first maleimide compound (A1) and the second maleimide compound (A2) relative to the total curable composition (100% by mass) is preferably 40%, 42%, 45%, 47%, 48%, or 50% by mass. Furthermore, the upper limit of the above-mentioned total content is preferably 100%, 99%, 98%, or 97% by mass. The above-mentioned upper and lower limits can be combined arbitrarily. Therefore, for example, in the curable composition of this embodiment, the total content of the first maleimide compound (A1) and the second maleimide compound (A2) relative to the total curable composition (100% by mass) is preferably 40% by mass or more and 100% by mass or less, the total content of the first maleimide compound (A1) and the second maleimide compound (A2) is more preferably 45% by mass or more and 100% by mass or less, and the total content of the first maleimide compound (A1) and the second maleimide compound (A2) is even more preferably 50% by mass or more and 100% by mass or less.

[0252] In the curable composition of this embodiment, the lower limit of the total content of the first maleimide compound (A1), the second maleimide compound (A2), and the inorganic filler relative to the total curable composition (100% by mass) is preferably 80%, 82%, 84%, 86%, or 88% by mass. Furthermore, the upper limit of the above-mentioned total content is preferably 100%, 99%, 98%, or 97% by mass. Similar to the range of the total content of the first maleimide compound (A1) and the second maleimide compound (A2), the above-mentioned upper and lower limits can be arbitrarily combined.

[0253] In the curable composition of this embodiment, the lower limit of the total content of the first maleimide compound (A1), the second maleimide compound (A2), and the additive relative to the total curable composition (100% by mass) is preferably 43%, 45%, 48%, 50%, or 53% by mass. Furthermore, the upper limit of the above-mentioned total content is preferably 100%, 99%, 98%, or 97% by mass. Similar to the range of the total content of the first maleimide compound (A1) and the second maleimide compound (A2), the above-mentioned upper and lower limits can be combined arbitrarily.

[0254] [cured material]

[0255] The cured product disclosed herein is preferably obtained from the above-described curable composition. The cured product is obtained by subjecting the above-described curable composition to a curing reaction. The above-described curable composition can be obtained by uniformly mixing the above-described components (e.g., curing agent, compounding agent), and the cured product can be easily prepared using methods similar to those known in the past. Examples of the above-described cured products include laminates, castings, adhesive layers, coatings, films, and other molded cured products.

[0256] The aforementioned curing (thermocuring) reaction can be easily carried out without a catalyst, but for a faster reaction, the addition of polymerization initiators such as organic peroxides and azo compounds, or basic catalysts such as phosphine compounds and tertiary amines, is effective. Examples include benzoyl peroxide, dicumyl peroxide, azobisisobutyronitrile, triphenylphosphine, triethylamine, and imidazoles, preferably in amounts of 0.05 to 5% by mass of the total curable resin composition.

[0257] [Heat-resistant materials and electronic materials]

[0258] The cured product obtained from the curable composition containing the first maleimide compound (A1) and the second maleimide compound (A2) of this disclosure exhibits excellent low moisture absorption and low dielectric properties, making it suitable for use in heat-resistant components or electronic components. It is particularly suitable for use in prepregs, circuit boards, semiconductor sealing materials, semiconductor devices, multilayer films, multilayer substrates, adhesives using conductive pastes, and photoresist materials. Furthermore, it is suitable for use as a matrix resin for fiber-reinforced resins, and is particularly suitable as a prepreg with high heat resistance or low dimensional change rate. In addition, the second maleimide compound (A2) contained in the above-described curable composition exhibits excellent solubility in various solvents, thus enabling coating. The heat-resistant components and electronic components thus obtained are suitable for a wide range of applications, including, but not limited to, industrial machinery parts, general machinery parts, automotive / railway / vehicle parts, aerospace-related parts, electronic / electrical parts, building materials, container / packaging components, household goods, sports / leisure products, and wind power generation frame components.

[0259] Hereinafter, representative articles (circuit boards, semiconductor sealing materials, semiconductor devices, prepregs, multilayer substrates, multilayer films, conductive pastes) manufactured using the curable resin compositions of the present invention will be described by way of example.

[0260] [Circuit board]

[0261] This disclosure pertains to a circuit board as a laminate of the prepreg and copper foil described below. As a method for obtaining a printed circuit board from the curable composition of this embodiment, an example is to laminate the prepreg using conventional methods, appropriately overlap the copper foil, and heat and press it at 170-300°C for 10 minutes to 3 hours under a pressure of 1-10 MPa.

[0262] [Semiconductor sealing materials]

[0263] This disclosure pertains to a semiconductor sealing material containing the curable composition of this embodiment. The semiconductor sealing material obtained using the curable composition of this embodiment improves hygroscopicity and reduces dielectric loss tangent by using the first maleimide compound (A1) and the second maleimide compound (A2) of this disclosure. Therefore, it exhibits excellent processability, moldability, and reflow resistance during the manufacturing process, making it a preferred method.

[0264] The curable composition of this embodiment used in the aforementioned semiconductor sealing material can contain an inorganic filler. It should be noted that the filling rate of the inorganic filler, relative to 100 parts by weight of the curable composition of this embodiment, can be, for example, in the range of 0.5 to 1200 parts by weight. Furthermore, as described above, examples of such inorganic fillers include barium sulfate, barium titanate, amorphous silica, crystalline silica, Noiburg silica, fused silica, spherical silica, talc, clay, magnesium carbonate, calcium carbonate, alumina, aluminum hydroxide, silicon nitride, and aluminum nitride.

[0265] As a method for obtaining the aforementioned semiconductor sealing material, methods can be listed such as further using an extruder, kneader, roller, etc., to fully melt and mix curing accelerators and / or additives, which are any components, to achieve uniformity in the curable composition of this embodiment. When used as a high thermal conductivity semiconductor sealing material for power transistors and power ICs, highly filled materials such as crystalline silica, alumina, and silicon nitride, which have thermal conductivity higher than fused silica, can be used, or fused silica, crystalline silica, alumina, and silicon nitride can be used. Regarding the filling rate, inorganic fillers are preferably used in the range of 30 to 95 parts by mass relative to 100 parts by mass of the curable composition. More preferably, 70 parts by mass or more, and even more preferably 80 parts by mass or more, are used to improve flame retardancy, moisture resistance, solder crack resistance, and reduce the coefficient of linear expansion.

[0266] [Semiconductor Devices]

[0267] This disclosure pertains to a semiconductor device comprising a cured semiconductor sealing material as described above. Semiconductor devices obtained using the semiconductor sealing material obtained with the curable composition of this embodiment exhibit low viscosity and excellent flowability due to the use of the first maleimide compound (A1) and the second maleimide compound (A2) of this disclosure. Furthermore, they improve hygroscopicity, thermal modulus of elasticity, and adhesion to metallic materials, thus offering excellent processability, moldability, and reflow resistance during manufacturing, making them a preferred method.

[0268] As a method for obtaining the above-mentioned semiconductor device, one example is to form the semiconductor sealing material by means of casting, transfer molding machine, injection molding machine, etc., and then heat and cure it in a temperature range of room temperature (20°C) to 250°C.

[0269] [Prepreg]

[0270] This disclosure pertains to a prepreg having a reinforcing substrate and a curable composition of this embodiment impregnated in the reinforcing substrate. As a method for obtaining the prepreg from the curable composition, one method includes impregnating a reinforcing substrate (paper, glass cloth, glass nonwoven fabric, aramid paper, aramid cloth, glass mat, glass yarn bundle, etc.) with an organic solvent (described later), and then heating the prepreg at a temperature corresponding to the type of solvent used, preferably 50 to 170°C, thereby partially curing (or not curing) the curable composition to obtain the prepreg. The mass ratio of the curable composition to the reinforcing substrate used in this process is not particularly limited, but it is generally preferred to prepare the prepreg with a resin content of 20 to 60% by mass.

[0271] In this embodiment, the semi-cured product of the curable composition is obtained by adjusting the heating temperature and heating time to stop the curing reaction midway, preventing it from completing. Furthermore, the semi-cured product may have a degree of curing of 5% or less (below 85%). On the other hand, the cured product in this embodiment may have a higher degree of curing than the semi-cured product.

[0272] It should be noted that the degree of curing of the semi-cured material can be determined by DSC measurement of the heat release during curing of the curing composition and the heat release during curing of its semi-cured material, and calculated by the following formula.

[0273] Degree of Curing (%) = [1 - (Heat release during curing of the semi-cured product / Heat release during curing of the curable composition)] × 100

[0274] Examples of organic solvents used in the manufacture of the prepreg in this embodiment include methyl ethyl ketone, acetone, dimethylformamide, methyl isobutyl ketone, methoxypropanol, cyclohexanone, methyl cellosolve, ethyl diethylene glycol acetate, and propylene glycol monomethyl ether acetate. The selection and appropriate amount of these solvents can be chosen according to the intended use. For example, in the case of further manufacturing a printed circuit board from the prepreg as described below, polar solvents with a boiling point of 160°C or lower, such as methyl ethyl ketone, acetone, and dimethylformamide, are preferred. Furthermore, the non-volatile components are preferably used at a ratio of 40-80% by mass. Additionally, the reinforcing substrate used in the manufacture of the prepreg in this embodiment can be woven fabric, nonwoven fabric, felt, or paper made of inorganic or organic fibers such as glass fiber, polyester fiber, or polyamide fiber; these can be used individually or in combination.

[0275] The heat treatment conditions for the prepreg in this embodiment can be appropriately selected according to the type and amount of organic solvent, catalyst, and various additives used, and are usually carried out at a temperature of 80 to 220°C for 3 to 30 minutes.

[0276] [Laminated substrate]

[0277] As a method for obtaining a multilayer substrate from the curable composition of this embodiment, the following steps 1 to 3 can be described. In step 1, firstly, the curable composition, appropriately formulated with rubber, fillers, etc., is applied to a circuit board on which a circuit is formed using a spraying method, curtain coating method, etc., and then cured. In step 2, as needed, predetermined through-holes, etc., are made on the circuit board coated with the curable composition, then treated with a roughening agent, and its surface is washed with hot water to form an uneven surface on the substrate, and then a metal such as copper is plated. In step 3, the operations of steps 1 to 2 are repeated sequentially as desired, alternately laminating a resin insulating layer and a conductor layer with a predetermined circuit pattern to form the multilayer substrate. It should be noted that in the above steps, the through-holes can be made after the outermost resin insulating layer is formed. In addition, regarding the multilayer substrate in this embodiment, a resin-coated copper foil, which is semi-cured on a copper foil, can be heated and pressed onto a wiring substrate on which a circuit is formed by heating at 170 to 300°C. This can create a roughened surface, save the plating process, and produce a multilayer substrate.

[0278] [Laminated membrane]

[0279] This disclosure pertains to a multilayer film containing the curable composition of this embodiment. A method for manufacturing the multilayer film of this embodiment can be exemplified by the following steps: applying the curable composition onto a support film (Y), drying it, forming a layer of the curable composition on the support film (Y), and thus producing an adhesive film for a multilayer printed circuit board.

[0280] When manufacturing multilayer films from curable compositions, it is important that the film softens under the lamination temperature conditions (typically 70–140°C) in a vacuum lamination process. During lamination of the circuit board, it should exhibit resin flowability (resin flow) capable of filling vias or through-holes present in the circuit board. Preferably, the aforementioned components are formulated in a manner that exhibits such characteristics. It should be noted that, in order to prevent localized differences in characteristic values ​​caused by phase separation or other factors, uniform appearance is required in the resulting multilayer film and circuit board (copper clad laminate, etc.).

[0281] Here, the diameter of the through-hole in the multilayer printed circuit board is typically 0.1–0.5 mm, and the depth is typically 0.1–1.2 mm. It is generally preferred that resin filling be performed within this range. It should be noted that when laminating both sides of the circuit board, it is preferable to fill approximately 1 / 2 of the through-hole.

[0282] Regarding the method for manufacturing the aforementioned adhesive film, specifically, after preparing the aforementioned curable composition in the form of a varnish, the varnish-like composition is coated onto the surface of a support film (Y), and then the organic solvent is dried by heating or blowing hot air to form a composition layer (X) composed of the curable composition, thereby enabling the manufacture. As the aforementioned organic solvent, ketones such as acetone, methyl ethyl ketone, and cyclohexanone are preferably used; acetates such as ethyl acetate, butyl acetate, cellolytic acetate, propylene glycol monomethyl ether acetate, and carbitol acetate; carbitols such as cellolytic agents and butyl carbitol; aromatic hydrocarbons such as toluene and xylene; and dimethylformamide, dimethylacetamide, and N-methylpyrrolidone. Furthermore, it is preferable to use a proportion of 30 to 60% by mass for the non-volatile components.

[0283] The thickness of the formed composition layer (X) is preferably greater than or equal to the thickness of the conductor layer. The thickness of the conductor layer in the circuit board is typically in the range of 5 to 70 μm, therefore the thickness of the resin composition layer is preferably 10 to 100 μm. It should be noted that the composition layer (X) in this embodiment can be protected by the protective film described later. By using the protective film, the adhesion of dust, scratches, etc., on the surface of the resin composition layer can be prevented.

[0284] The aforementioned support film (Y) and protective film can be exemplified by polyolefins such as polyethylene, polypropylene, and polyvinyl chloride; polyesters such as polyethylene terephthalate (hereinafter sometimes abbreviated as "PET") and polyethylene naphthalate; polycarbonate, polyimide, and further examples include release paper, copper foil, aluminum foil, and other metal foils. It should be noted that, in addition to MAD treatment and corona treatment, the support film and protective film can also undergo release treatment. The thickness of the support film is not particularly limited, typically ranging from 10 to 150 μm, preferably in the range of 25 to 50 μm. Furthermore, the thickness of the protective film is preferably set to 1 to 40 μm.

[0285] The aforementioned support film (Y) is peeled off after being laminated onto the circuit board or after forming an insulating layer through heat curing. Peeling off the support film (Y) after the adhesive film has been heat-cured prevents the adhesion of dust and other contaminants during the curing process. When peeling is performed after curing, the support film is typically pre-treated with a demolding process.

[0286] It should be noted that multilayer printed circuit boards can be manufactured from the laminated film obtained as described above. For example, when the resin composition layer (X) is protected by a protective film, after peeling them off, lamination is performed on one or both sides of the circuit board by, for example, vacuum lamination, in a manner that the resin composition layer (X) is directly in contact with the circuit board. The lamination method can be intermittent or continuous using rollers. In addition, the laminated film and the circuit board can be preheated as needed before lamination (preheating). Regarding the lamination conditions, the lamination temperature is preferably set to 70 to 140°C, and the lamination pressure is preferably set to 1 to 11 kgf / cm². 2 (9.8×10 4 ~107.9×10 4 N / m 2 It is preferable to perform lamination under reduced pressure, with the air pressure set to below 20 mmHg (26.7 hPa).

[0287] <Conductive Paste>

[0288] As a method for obtaining conductive paste from the curable composition of the present invention, a method of dispersing conductive particles in the composition can be cited as an example. The above-mentioned conductive paste can be formulated into a paste resin composition for circuit connection or an anisotropic conductive adhesive, depending on the type of conductive particles used.

[0289] [Example]

[0290] The present invention is specifically illustrated through examples and comparative examples. Unless otherwise specified, "parts" and "%" refer to mass. Furthermore, the physical properties of the synthesized second maleimide compound (A2) were determined as follows, and are shown in Table 1.

[0291] (1) Amine equivalent

[0292] The amine equivalent of intermediate amine compound (c) was determined by the following method.

[0293] In a 500 mL Erlenmeyer flask with a stopper, accurately weigh approximately 2.5 g of the intermediate amine compound (c), 7.5 g of pyridine, 2.5 g of acetic anhydride, and 7.5 g of triphenylphosphine as the sample. Then, install a cooling tube and heat under reflux in an oil bath set at 120 °C for 150 minutes.

[0294] After cooling, add 5.0 mL of distilled water, 100 mL of propylene glycol monomethyl ether, and 75 mL of tetrahydrofuran. Titrate with 0.5 mol / L potassium hydroxide-ethanol solution using potentiometric titration. Perform a blank test using the same method to correct the titration.

[0295] Amine equivalent (g / equivalent) = (S × 2,000) / (blank - A)

[0296] S: Amount of sample (g)

[0297] A: Volume (mL) of 0.5 mol / L potassium hydroxide-ethanol solution consumed.

[0298] Blank: The volume (mL) of 0.5 mol / L potassium hydroxide-ethanol solution consumed in the blank test.

[0299] (2) GPC determination

[0300] Using the following measuring apparatus and conditions, the number-average molecular weight (Mn), weight-average molecular weight (Mw), and molecular weight distribution (Mw / Mn) of the second maleimide compound (A2) obtained in the Examples and Comparative Examples were calculated.

[0301] "Measuring device"

[0302] "HLC-8320GPC" manufactured by TOSOH Co., Ltd.

[0303] "Measurement conditions"

[0304] Column: Guard column "HXL-L" made by TOSOH Co., Ltd. + "TSK-GELG2000HXL" made by TOSOH Co., Ltd. + "TSK-GEL G2000HXL" made by TOSOH Co., Ltd. + "TSK-GEL G3000HXL" made by TOSOH Co., Ltd. + "TSK-GEL G4000HXL" made by TOSOH Co., Ltd.

[0305] Detector: RI (Differential Refractometer)

[0306] Data processing: "GPC Workstation EcoSEC-WorkStation" manufactured by TOSOH Corporation

[0307] Measurement conditions: column temperature 40℃

[0308] Expand solvent tetrahydrofuran

[0309] Flow rate 1.0 ml / min

[0310] Standard: Based on the above-mentioned "GPC Workstation EcoSEC-WorkStation" test manual, use the following monodisperse polystyrene with known molecular weight.

[0311] (Using polystyrene)

[0312] "A-500" made by TOSOH Co., Ltd.

[0313] "A-1000" made by TOSOH Co., Ltd.

[0314] "A-2500" manufactured by TOSOH Co., Ltd.

[0315] "A-5000" made by TOSOH Co., Ltd.

[0316] "F-1" manufactured by TOSOH Co., Ltd.

[0317] "F-2" manufactured by TOSOH Co., Ltd.

[0318] "F-4" manufactured by TOSOH Co., Ltd.

[0319] "F-10" manufactured by TOSOH Co., Ltd.

[0320] "F-20" manufactured by TOSOH Co., Ltd.

[0321] "F-40" manufactured by TOSOH Co., Ltd.

[0322] "F-80" manufactured by TOSOH Co., Ltd.

[0323] "F-128" manufactured by TOSOH Co., Ltd.

[0324] Sample: 50 μl was obtained by filtering a tetrahydrofuran solution of the second maleimide compound (A2) obtained in the synthesis example, which was calculated as 1.0% by mass of resin solids, through a microfilter.

[0325] (3) FD-MS determination

[0326] The second maleimide compound (A2) obtained in the examples was determined by FD-MS chromatography using the following measuring apparatus and conditions.

[0327] Measurement device: JMS-T100GC AccuTOF

[0328] Measurement conditions

[0329] Measurement range: m / z = 4.00~2000.00

[0330] Rate of change: 51.2 mA / min

[0331] Final current value: 45mA

[0332] Cathode voltage: -10kV

[0333] Recording interval: 0.07 sec

[0334] (4) 13 C-NMR determination

[0335] The second maleimide compound (A2) obtained in the examples 13 C-NMR chromatography was performed using the following apparatus and conditions.

[0336] 13 C-NMR: "JNM-ECZ400S" manufactured by JEOL RESONANCE

[0337] Resonant frequency: 100MHz

[0338] Points earned: 4000 times

[0339] Solvent: Chloroform-d

[0340] Sample concentration: 12% by mass

[0341] Buffer reagent: Chromium acetylacetonate (III)

[0342] (5) Synthesis of the second maleimide compound (A2)

[0343] <Synthetic Example 1> Synthesis of polymaleimide compound (X)

[0344] (I) Synthesis of intermediate amine compound (c-1)

[0345] In a flask equipped with a thermometer, cooling tube, Dean-Stark trap, and stirrer, 242.4 g (2.0 mol) of 2-ethylaniline, 242 g of xylene, and 80 g of activated clay were added. The mixture was heated to 130°C with stirring and maintained for 30 minutes. Then, 272.0 g of DVB-810 (a mixture of divinylbenzene / ethylstyrene (divinylbenzene / ethylstyrene = 81 / 19 (mol)%), manufactured by JITCO Chemicals & Materials) was added dropwise over 2 hours, allowing the reaction to proceed directly for 1 hour. The temperature was then raised to 190°C over 6 hours and maintained for 10 hours. After the reaction, the mixture was cooled to 100°C with air, diluted with 300 g of toluene, and the activated clay was removed by filtration. Solvent and unreacted low-molecular-weight substances were removed by distillation under reduced pressure to obtain the intermediate amine compound (c-1). The amine equivalent of the intermediate amine compound (c-1) was 214 g / equivalent.

[0346] (II) Maleimide

[0347] In a 2L flask equipped with a thermometer, cooling tube, Dean-Stark trap, and stirrer, 117.7 g (1.2 mol) of maleic anhydride and 700 g of toluene were added and stirred at room temperature. Next, a mixed solution of 214 g (1 equivalent) of intermediate amine compound (c-1) and 175 g of DMF was added dropwise over 1 hour, and the reaction was allowed to proceed for 2 hours. Then, 37.1 g of p-toluenesulfonic acid monohydrate was added to the reaction solution, and the mixture was heated to 115°C. After cooling and separating the azeotropic water and toluene under reflux, only the toluene was returned to the system for a 5-hour dehydration reaction. After air cooling to room temperature, the mixture was neutralized with 49% NaOH. Then, toluene and water were removed by vacuum distillation at 60°C. 600 g of MEK (methyl ethyl ketone) was added to the remaining DMF solution in the flask. The solution was then heated to 60°C and subjected to three separate treatments with 200 g of deionized water to remove salts from the solution. After further drying with sodium sulfate, the mixture was concentrated under reduced pressure, and the resulting reactants were dried under vacuum at 80°C to obtain polymaleimide compound (X) as the second maleimide compound (A2). The chemical structure and properties of this polymaleimide compound (X) were determined using GPC, FD-MS, and... 13 C-NMR confirmation. The measurement results are shown below. Figures 1A to 1C In addition, according to GPC measurements, the Mn of polymaleimide compound (X) is 998, the Mw is 367,834, and the Mw / Mn ratio is 368.697.

[0348] <Examples 1-4 and Comparative Examples 1-4>

[0349] <<Preparation of Curable Compositions and Production of Cured Products>>

[0350] As the first maleimide compound (A1), the first maleimide compound (1) (the maleimide compound A-1 described in Synthesis Example 1 of Patent No. 6797356, a bismaleimide compound having an indane skeleton described (hereinafter chemical formula (7)) is used. A1 =1.47, molecular weight distribution (Mw / Mn) =1.81), first maleimide compound (2) ("BMI-1000" manufactured by Yamato Chemical Industry Co., Ltd. (chemical formula (8) below), and first maleimide compound (3) ("BMI-5100" manufactured by Yamato Chemical Industry Co., Ltd. (chemical formula (9) below).

[0351]

[0352] In addition, as the second maleimide compound (A2), the polymaleimide compound (X) obtained in the above synthesis example 1 was used.

[0353] The first maleimide compound (A1), the second maleimide compound (A2), and DCPO (“PERCUMYL D”, manufactured by Nippon Oil Co., Ltd., Dicumyl Peroxide) as a curing catalyst were mixed in the proportions shown in Table 1 below to prepare the curable compositions of Examples 1 to 4 and Comparative Examples 1 to 4.

[0354] Next, the curable compositions of Examples 1-4 and Comparative Examples 1-4 were cured under the following curing conditions to prepare cured products corresponding to the curable compositions of Examples 1-4 and Comparative Examples 1-4, respectively. Furthermore, the dielectric loss tangent and glass transition temperature were evaluated using the methods described below. The results are shown in Table 1.

[0355] <<Curing Conditions>>

[0356] After being vacuum-pressed at 200°C for 2 hours, it is then heated and cured at 250°C for 2 hours.

[0357] Thickness of the formed plate: 1.3mm

[0358] <<Evaluation of Dielectric Constant and Dielectric Loss Tangent>>

[0359] According to JIS-C-6481, using an Agilent Technologies network analyzer "E8362C", the dielectric constant (Dk) and dielectric loss tangent (Df) of a test piece after it has been completely dried and stored indoors at 23°C and 50% humidity for 24 hours were determined by the void resonance method at 10 GHz.

[0360] <<Glass Transition Temperature>>

[0361] For each cured product obtained by curing the curable compositions in this embodiment and comparative example, a size of 5 mm in width and 54 mm in length was cut out and used as a test piece. The test piece was evaluated using a viscoelasticity measuring device (DMA: Hitachi High-Tech Corporation solid viscoelasticity measuring device "DMS6100", deformation mode: double-sided support bending, measurement mode: sinusoidal vibration, frequency 1 Hz, heating rate 3 °C / min), with the temperature at which the elastic modulus changed the most (and the tanδ change rate was also the most) being taken as the glass transition temperature (Tg(°C)).

[0362] [Table 1]

[0363]

[0364] The results shown in Table 1 above confirm that, when comparing Examples 1-4 with Comparative Examples 1-4, it can be confirmed that by using the curable compositions of Examples 1-4 containing the first maleimide compound (A1) and the second maleimide compound (A2), cured products with low dielectric loss tangent, high glass transition temperature, and resistance to cracking can be formed. Furthermore, it has been confirmed that by using the curable compositions of Examples 1-4 containing the first maleimide compound (A1) and the second maleimide compound (A2), cured products with low dielectric loss tangent, high glass transition temperature, and resistance to cracking can be formed even in the frequency band above Sub6.

[0365] [Industry availability]

[0366] According to this disclosure, it is possible to provide curable compositions and cured products thereof that are difficult to crack during curing and exhibit low dielectric properties and high glass transition temperature.

Claims

1. A curable composition, characterized in that, A curable composition comprising a first maleimide compound (A1) and a second maleimide compound (A2) having structural units different from those contained in the first maleimide compound (A1). The second maleimide compound (A2) is a compound having a monocyclic or condensed polycyclic aromatic group and a maleimide group connected by two or more straight-chain or branched alkylene groups. The first maleimide compound (A1) is a compound represented by the general formula (A1-2). The second maleimide compound (A2) has the structural unit shown in the following general formula (1). In the above general formula (A1-2), R a Each of these groups independently represents an alkyl, alkoxy, or alkylthio group having 1 to 10 carbon atoms; an aryl, aryloxy, or arylthio group having 6 to 10 carbon atoms; a cycloalkyl, halogen, nitro, hydroxyl, or mercapto group having 3 to 10 carbon atoms. p A1 and p A2 p represents an integer value from 0 to 4. A1 and p A2 When R is 2 to 4, a Within the same ring, they can be the same or different. R b Each of these groups independently represents an alkyl, alkoxy, or alkylthio group having 1 to 10 carbon atoms; an aryl, aryloxy, or arylthio group having 6 to 10 carbon atoms; a cycloalkyl, halogen, hydroxyl, or mercapto group having 3 to 10 carbon atoms. q A1 and q A2 Each of the integer values ​​from 0 to 3 can be represented independently, q A1 and q A2 When R is 2 to 3, b Within the same ring, they can be the same or different. n A1 The average number of repeating units represents a value ranging from 0.95 to 10.

0. In the above general formula (1), R 1 Each can be independently represented as an alkyl group. R 2 Each of these groups independently represents an alkyl, alkoxy, or alkylthio group having 1 to 10 carbon atoms; an aryl, aryloxy, or arylthio group having 6 to 10 carbon atoms; a cycloalkyl group having 3 to 10 carbon atoms; a halogen atom; a hydroxyl group; or a mercapto group. R 3 R 4 R 5 and R 6 Each can independently represent a hydrogen atom or a methyl group, and R 3 and R 4 One side is a hydrogen atom and the other side is a methyl group, R 5 and R 6 One side is a hydrogen atom and the other side is a methyl group. X 1 The substituents represented by the following general formula (x) are: In the general formula (x), R 7 and R 8 Each can independently represent a hydrogen atom or a methyl group, and R 7 and R 8 One side is a hydrogen atom and the other side is a methyl group, R 9 Each of these groups independently represents an alkyl, alkoxy, or alkylthio group having 1 to 10 carbon atoms; an aryl, aryloxy, or arylthio group having 6 to 10 carbon atoms; a cycloalkyl group having 3 to 10 carbon atoms; a halogen atom; a hydroxyl group; or a mercapto group, where t represents an integer from 0 to 4. r represents the number of connections with X. 1 X of the benzene ring 1 The average of the substitution numbers, where p represents an integer from 1 to 3, q ​​represents an integer from 0 to 4, and k represents an integer from 1 to 100.

2. The curable composition according to claim 1, wherein the second maleimide compound (A2) is a polymaleimide compound.

3. The cured product of the curable composition according to claim 1 or 2.

4. A prepreg having a reinforcing substrate and a semi-cured product of the curable composition of claim 1 or 2 impregnated in the reinforcing substrate.

5. A circuit board, comprising a laminate having the prepreg and copper foil as described in claim 4.

6. A laminated film comprising the curable composition of claim 1 or 2.

7. A semiconductor sealing material comprising the curable composition of claim 1 or 2.

8. A semiconductor device comprising a cured form of the semiconductor sealing material of claim 7.

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