TWI841328B - Curable composition, cured product, prepreg, circuit board, build-up film, semiconductor packaging material and semiconductor device - Google Patents

Abstract

[Topic] The present disclosure aims to provide a curable composition and a cured product thereof which exhibit low dielectric loss factor and low moisture absorption rate during curing. [Solution] The present disclosure is a curable composition characterized by containing: a polymaleimide compound (A) containing a monocyclic or condensed polycyclic aromatic group having two or more linear or branched alkylene groups bonded thereto, and an amine compound (B).

Description

Curable composition, cured product, prepreg, circuit board, build-up film, semiconductor packaging material and semiconductor device

The present disclosure relates to a curable composition, a cured product, a prepreg, a circuit substrate, a build-up film, a semiconductor packaging material, and a semiconductor device.

Epoxy resin or BT (bismaleimide-tris(II) Prepregs obtained by impregnating glass cloth with thermosetting resins such as ) resins and heating and drying, 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, package substrates, which are a type of printed wiring boards that serve as interposers for mounting semiconductors, are being made thinner, and warping of the package substrates during mounting has become a problem. Therefore, in order to suppress the warping of the package substrates during mounting, materials that exhibit high heat resistance are required. In recent years, as the speed and frequency of signals continue to advance, it is hoped that a thermosetting composition can be provided that can form a cured product that can maintain a sufficiently low dielectric constant and exhibit a sufficiently low dielectric dissipation factor in such an environment. In particular, in recent times, various electronic material applications, especially cutting-edge material applications, require further improvements in performance represented by heat resistance and dielectric properties, as well as materials and compositions that have these properties. In response to these requirements, maleimide resins have attracted attention as materials that have both heat resistance and low dielectric constants and low dielectric dissipation factors. However, although conventional maleimide resins have shown high heat resistance, they have high hygroscopicity and their dielectric properties (dielectric constant and dielectric dissipation factor values) have not reached the level required for cutting-edge material applications. 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 a printed circuit board having a dielectric constant of 4.0 or less and having heat resistance without loss. [Prior Art Document] [Patent Document]

[Patent Document 1] Japanese Patent Application Laid-Open No. 5-247202

[Problems to be solved by the invention]

However, the thermosetting resin composition of Patent Document 1 has not studied the dielectric dissipation factor value, so the dielectric constant and dielectric dissipation factor value do not reach the level required for cutting-edge material applications, and cannot have low moisture absorption at high temperatures, low dielectric constant and low dielectric dissipation factor. In addition, since the transmission loss increases with high frequency, the circuit substrate material requires a reduction in transmission loss in the high frequency region. However, in the technology of Patent Document 1, only the dielectric properties of the currently used frequency band (ranging from hundreds of MHz to 3GHz) are studied, but there is no research on whether it can correspond to the technology of the so-called 5th generation mobile communication system (5G) using frequency bands above Sub6 (for example, above 3.6GHz). Therefore, the technical problem to be solved by the present disclosure is to provide a curable composition, a cured product, a prepreg, a circuit substrate, a build-up film, a semiconductor packaging material and a semiconductor device that has low moisture absorption during curing and exhibits low dielectric loss factor and low dielectric constant. [Means for solving the problem]

The inventors of the present invention have repeatedly studied to solve the above problems, and found that by using a curable composition, it is possible to highly combine low hygroscopicity during curing with low dielectric loss tangent and low dielectric constant, thereby completing the present invention; wherein the curable composition contains: a polymaleimide compound (A) containing a monocyclic or condensed polycyclic aromatic ring containing two or more linear or branched alkylene groups, and an amine compound (B). [Effect of the invention]

According to the present disclosure, a curable composition, a cured product, a prepreg, a circuit substrate, a build-up film, a semiconductor packaging material, and a semiconductor device can be provided, which can highly combine low hygroscopicity, low dielectric constant, and low dielectric dissipation factor during curing. According to the present disclosure, a curable composition, a cured product, a prepreg, a circuit substrate, a build-up film, a semiconductor packaging material, and a semiconductor device can be provided, which can highly combine low hygroscopicity, low dielectric constant, and low dielectric dissipation factor during curing even in a frequency band above Sub6. Such a curable composition is particularly useful in electronic component packaging material applications, etc.

[Form used to implement the invention]

The following describes in detail the embodiments of the present invention (hereinafter referred to as "the present embodiments"), but the present disclosure is not limited to the following description and can be implemented with various modifications within the scope of the gist.

[Terms] The term "reaction raw material" as used in this specification refers to a compound that is used to obtain the target compound through a chemical reaction such as combination or decomposition and partially constitutes the chemical structure of the target compound. Substances that serve as chemical reaction aids such as solvents and catalysts are excluded. In this specification, the term "reaction raw material" refers to, for example, when the target substance is a polymaleimide compound (A), a precursor compound (for example, an intermediate amine compound (c) formed by linking the following aromatic amine compounds (a) to each other via the following aromatic divinyl compound (b1)) through a chemical reaction. The "aromatic group" in the present specification is preferably an aromatic ring having 3 to 30 carbon atoms, and more preferably an aromatic ring having 4 to 26 carbon atoms. In addition, the "aromatic group" in the present specification may be substituted with a substituent such as an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a halogen atom. In addition, the "aromatic group" includes a heteroaromatic group, and may be substituted with -O-, -S-, or -N= so that -CH ₂ - or -CH= in the "aromatic group" is not adjacent to each other. Examples of the aromatic ring include a monocyclic aromatic ring and a condensed polycyclic aromatic ring. Examples of the monocyclic aromatic ring include benzene, furan, pyrrole, thiophene, imidazole, pyrazole, oxadiazole, isoxadiazole, thiazole, isothiazole, pyridine, pyrimidine, thiazolidine, , pyridine ,three As the aforementioned condensed polycyclic aromatic ring, there can be listed, for example, naphthalene, anthracene, phenanthrene, quinoline, isoquinoline, quinazoline, , pteridine, coumarin, indole, benzimidazole, benzofuran, acridine, etc. In addition, the hydrogen atom of the aromatic ring in the aromatic group may be substituted by, for example, 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, an aryl group having 1 to 12 carbon atoms, an aralkyl group having 1 to 12 carbon atoms, or a halogen atom. In addition, the so-called monovalent aromatic group refers to a group in which one hydrogen atom in the "aromatic group" is removed, the so-called divalent aromatic group refers to a group in which any two hydrogen atoms in the "aromatic group" are removed, and the so-called trivalent to hexavalent aromatic groups refer to a group in which 3 to 6 hydrogen atoms in the "aromatic group" are removed. Examples of the "aralkyl" in this specification include benzyl, diphenylmethyl, naphthylmethyl, etc. The hydrogen atom of the aromatic ring in the aralkyl group may be substituted by, for example, 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. In addition, the "aralkyl group" may be a divalent group obtained by removing any one hydrogen atom from the above-mentioned "aralkyl group". The "alkyl" in the present specification may be any of a linear, branched or cyclic structure, and examples thereof include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, dibutyl, tertiary butyl, n-pentyl, isopentyl, tertiary 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. Examples of the "cycloalkyl" in the present specification include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, methylcyclobutyl, norbornyl, or adamantyl. Examples of the "alkylthio" in the present specification include methylthio, ethylthio, propylthio, butylthio, octylthio, or 2-ethylhexylthio. Examples of the "alkenyl" in the present specification include ethenyl group, 1-propenyl, 2-propenyl, 2-butenyl, pentenyl, hexenyl, vinyl group, allyl, or isopropenyl. Examples of the "alkoxy" in the present specification include methoxy, ethoxy, propoxy, isopropoxy, butoxy, pentyloxy, hexyloxy, 2-ethylhexyloxy, octyloxy, or nonyloxy. The "aryl" in the present specification includes, for example, phenyl, naphthyl, phenanthrenyl, anthracenyl, azulenyl, tetrahydronaphthyl, etc. In addition, the "aryl" means that the hydrogen atom of the aromatic ring in the aryl may be substituted by, for example, 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. In addition, the "aryl" includes a divalent group obtained by removing any one hydrogen atom from the above-mentioned "aryl". The "aryloxy" in the present specification includes, for example, phenoxy, naphthyloxy, anthracenyloxy, phenanthrenyloxy, or pyreneoxy. The "arylthio" in the present specification includes, for example, phenylthio, naphthylthio, anthracenylthio, phenanthrenylthio, or pyrenethio. The "halogen atom" in this specification can be exemplified by fluorine atom, chlorine atom, bromine atom or iodine atom, etc. The "structural unit" in this specification refers to the (repeating) unit of the chemical structure formed during reaction or polymerization. In other words, it refers to the partial structure other than the structure of the chemical bond involved in the reaction or polymerization in the resulting compound formed by reaction or polymerization, i.e., the so-called residue.

[Curing composition] The curable composition of this embodiment contains: a polymaleimide compound (A) containing a monocyclic or condensed polycyclic aromatic ring having two or more linear or branched alkylene groups (hereinafter referred to as the polymaleimide compound (A)), and an amine compound (B). Since the polymaleimide compound (A) has a small proportion of polar functional groups in the chemical structure, the composition as a whole can have both excellent low dielectric properties and low hygroscopicity. In addition, by combining the polymaleimide compound (A) and the amine compound (B), even in the frequency band above Sub6, it is possible to have both low hygroscopicity, low dielectric constant and low dielectric dissipation factor during curing.

In the curable composition of the present embodiment, the blending ratio (mass fraction) of the polymaleimide compound (A) and the amine compound (B) is preferably 90:10 to 10:90, more preferably 80:20 to 20:80, and further preferably 75:25 to 25:75. By adjusting the blending ratio within the above range, it is preferred that excellent low hygroscopicity, low dielectric constant, and low dielectric loss factor can be exhibited.

The curable composition of the present embodiment may contain a curing agent (C) other than the amine compound (B) within the scope of not impairing the curing of the present invention. Furthermore, the curable composition of the present embodiment may also add other resins (D), curing accelerators or additives other than the polymaleimide compound (A) and the amine compound (B). Examples of the additives include flame retardants, inorganic fillers, silane coupling agents, mold release agents, antioxidants, light stabilizers, heat stabilizers, pigments, and emulsifiers.

Hereinafter, the essential components of the curable composition of the present embodiment: the polymaleimide compound (A) having a monocyclic or condensed polycyclic aromatic ring having two or more linear or branched alkylene groups and two or more maleimide groups and the amine compound (B) are described in detail, and then the curing agent (C), other resins (D), curing accelerators and additives other than the amine compound (B) which are optional components are described.

(Polymaleimide compound (A)) The polymaleimide compound (A) of the present embodiment is a compound having a monocyclic or condensed polycyclic aromatic ring bonded to two or more linear or branched alkylene groups and two or more maleimide groups. The monocyclic or condensed polycyclic aromatic ring bonded to two or more linear or branched alkylene groups refers to a divalent or higher group in which two or more linear or branched alkylene groups having 1 to 12 carbon atoms are present and one side of the two or more alkylene groups is bonded to the monocyclic or condensed polycyclic aromatic ring. Therefore, the number of linear or branched alkylene groups bonded to the monocyclic or condensed polycyclic aromatic ring is consistent with the valence of the alkylene group containing the aforementioned aromatic ring. In the present embodiment, the monocyclic or condensed polycyclic aromatic ring bonded to two or more linear or branched alkylene groups is preferably a divalent to tetravalent group, and more preferably a divalent to trivalent group. In the present embodiment, the monocyclic or condensed polycyclic aromatic ring bonded to two or more linear or branched alkylene groups is preferably a group represented by the following general formula (I). (In the above general formula (I), Ar ¹ represents a (2+h)-valent aromatic group, L ¹ , L ² and L ³ each independently represent an alkylene group having 1 to 12 carbon atoms, h represents an integer from 0 to 2, and * represents a bond with other atoms.) In the above general formula (I), when h is 0, the group represented by the general formula (I) is divalent, and when h is 2, the group represented by the general formula (I) is tetravalent. The maleimide group is preferably a group represented by the following general formula (II). (In the above general formula (II), Ar ² represents an aromatic group, a dotted line represents absence or a single bond, and * represents a bond with another atom.) In addition, in the general formula (II), a dotted line represents absence or a single bond. When the aforementioned dotted line is absent, the maleimide group of the above general formula (II) may become monovalent. On the other hand, when the aforementioned dotted line is a single bond, the maleimide group of the above general formula (II) may become divalent. A suitable polymaleimide compound (A) of the present embodiment is a compound having a structural unit represented by the following general formula (1), or a compound having an aromatic amine compound (a) having one or more alkyl groups and no more than three alkyl groups (hereinafter, also referred to as an aromatic amine compound (a)), an aromatic divinyl compound (b1) having two vinyl groups (hereinafter, also referred to as an aromatic divinyl compound (b1)), and maleic anhydride as reaction raw materials (1). (In the above general formula (1), ^R1 is independently an alkyl group, ^R2 is independently an alkyl group, an alkoxy group or an alkylthio group having 1 to 10 carbon atoms; an aryl group, an aryloxy group or an arylthio group having 6 to 10 carbon atoms; a cycloalkyl group having 3 to 10 carbon atoms; a halogen atom; a hydroxyl group; or an alkyl group; ^R3 , ^R4 , ^R5 and ^R6 are independently a hydrogen atom or a methyl group, and one of ^R3 and ^R4 is a hydrogen atom and the other is a methyl group, and one of ^R5 and ^R6 is a hydrogen atom and the other is a methyl group; ^X1 is a substituent represented by the following general formula (x); (In the general formula (x), ^R7 and ^R8 each independently represent a hydrogen atom or a methyl group, and one of ^R7 and ^R8 is a hydrogen atom and the other is a methyl group, and ^R9 each independently represents an alkyl group, an alkoxy group or an alkylthio group having 1 to 10 carbon atoms; an aryl group, an aryloxy group or an 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 hydroxyl group; and t represents an integer of 0 to 4.) r is the average value of the number of substitutions of ^X1 per benzene ring to which ^X1 is bonded, and represents a number of 0 to 4, p represents an integer of 1 to 3, q represents an integer of 0 to 4, and k represents an integer of 1 to 100.) Thereby, during curing, low hygroscopicity and low dielectric dissipation tangent can be more highly achieved.

<Preferred form of polymaleimide compound (A)> The polymaleimide compound (A) of this embodiment preferably has a structural unit represented by the above general formula (1). In the above general formula (1), when p is an integer greater than 2, multiple R ^1s may be the same or different from each other. When q is an integer greater than 2, multiple R ^2s may be the same or different from each other. When t is an integer greater than 2, multiple R ^9s may be the same or different from each other.

In the above general formula (1), R ¹ is independently an alkyl group having 1 to 10 carbon atoms, and more preferably an alkyl group having 1 to 6 carbon atoms. When p is an integer greater than 2, the plural R ^1s may be the same or different from each other. Preferred R ¹ in the general formula (1) is a methyl group, an ethyl group or an n-propyl group. In addition, the benzene ring to which R ¹ in the general formula (1) is bonded may be the benzene ring of the aromatic amine compound (a). In the above general formula (1), p is preferably 1 or 2. In addition, it is preferred that R ¹ is bonded to at least one of the 2-position, 3-position, 4-position, 5-position or 6-position of the benzene ring to which R 1 in the general formula ( ¹ ) is bonded.

In the above general formula (1), R ² each 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, more preferably an alkyl group having 1 to 10 carbon atoms, and further preferably an alkyl group having 1 to 6 carbon atoms. Furthermore, when q is an integer greater than 2, the plural R ^2s may be the same or different from each other. Preferred R ² in the general formula (1) is a methyl group, an ethyl group or an n-propyl group. In addition, the benzene ring to which R ² in the general formula (1) is bonded may be the benzene ring of the aromatic divinyl compound (b1). Furthermore, in the above general formula (1), q preferably represents 0, 1 or 2.

In the above general formula (1), one of ^R3 and ^R4 is a hydrogen atom and the other is a methyl group, and one of ^R5 and ^R6 is a hydrogen atom and the other is a methyl group. In this way, the reactivity of the unsaturated bond of the polymaleimide compound (A) itself can be maintained at a high level. If the proportion of alkyl groups in ^R3 , ^R4 , ^R5 and ^R6 in the above general formula (1) increases, it is considered that there is a tendency that the reactivity of the unsaturated bond of the polymaleimide compound (A) itself may decrease due to stereo hindrance. Therefore, if ^R3 , ^R4 , ^R5 and ^R6 are all alkyl groups, the reactivity of the unsaturated bond of the polymaleimide compound (A) itself is reduced, and a cured product cannot be formed efficiently.

In the above general formula (1), preferably ^X1 is represented by the above general formula (x), and in the above general formula (x), ^R7 represents a hydrogen atom, and ^R8 represents a methyl group. In the above general formula (x), each ^R9 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; more preferably an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms; further preferably an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 10 carbon atoms. In the above general formula (x), t preferably represents an integer of 0 to 4, and more preferably an integer of 0 to 3. When t is an integer of 2 or more, the plural ^R9s may be the same or different from each other.

In the above general formula (1), r means the average value of the number of substitutions of ^X1 per benzene ring bonded to ^X1 , and is preferably in the range of 0 to 4, and more preferably in the range of 0 to 3. In the above general formula (1), k represents the number of repeating units, and is preferably an integer of 1 to 100, more preferably an integer of 1 to 90, and even more preferably an integer of 1 to 80.

<Other preferred forms of the polymaleimide compound (A)> As another preferred form of the polymaleimide compound (A) of this embodiment, an aromatic amine compound (a) having 1 or more and 3 or less alkyl groups, an aromatic divinyl compound (b1) having 2 vinyl groups, and maleic anhydride may be used as the reaction raw material (1). At this time, in this embodiment, an aromatic monovinyl compound (b2) having 1 vinyl group (hereinafter, also referred to as the aromatic monovinyl compound (b2)) may be further contained in the aforementioned reaction raw material (1). In addition, the polymaleimide compound (A) of the present embodiment is preferably a polymaleimide compound (A) using an intermediate amine compound (c) and maleic anhydride as reaction materials (3), wherein the intermediate amine compound (c) is an aromatic amine compound (a) having 1 to 3 alkyl groups cross-linked with each other through an aromatic divinyl compound (b1) having 2 vinyl groups. Furthermore, the intermediate amine compound (c) is preferably a compound using an aromatic amine compound (a) having 1 to 3 alkyl groups, an aromatic divinyl compound (b1) having 2 vinyl groups, and an aromatic monovinyl compound (b2) having 1 vinyl group as reaction materials (2). In other words, the intermediate amine compound (c) in the present embodiment preferably has a structure in which a structural unit of an aromatic amine compound (a) is chemically linked to a structural unit of an aromatic divinyl compound (b1) having two vinyl groups, and optionally has a structural unit of an aromatic monovinyl compound (b2) chemically bonded to the aforementioned aromatic ring in the structural unit of the aforementioned aromatic amine compound (a), wherein the aromatic amine compound (a) has an aromatic ring bonded to an amine group (including a substituted amine group in which the hydrogen atom of the amine group is further substituted by an alkyl group having 1 to 6 carbon atoms), and has more than 1 and less than 3 alkyl groups on the aforementioned aromatic ring. Moreover, the polymaleimide compound (A) in the present embodiment has a structure in which the amine group (including _-NH2 and substituted amine group) bonded to the aromatic ring of the aforementioned intermediate amine compound (c) is substituted with an N-substituted maleimide ring. Therefore, the "polymaleimide compound (A)" in the present embodiment and the "intermediate amine compound (c)" of the precursor of the "polymaleimide compound (A)" are polymer compounds that are different in that the amine group (including _-NH2 and substituted amine group) bonded to the aromatic ring is substituted with an N-substituted maleimide ring. In addition, the structural unit of the aromatic amine compound (a) mentioned above refers to a group obtained by removing two hydrogen atoms from the aromatic ring of the aromatic amine compound (a). For example, when the aromatic amine compound (a) is represented by the general formula (a) described later, the group formed by removing two hydrogen atoms from the benzene ring of the general formula (a) is referred to as 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 formed by cleaving the unsaturated bonds of the two vinyl groups of the aromatic divinyl compound (b1). In the present embodiment, since the aromatic amine compound (a) having a specific aromatic ring structure is used as a reaction raw material, it becomes easy to control the reaction site with the aromatic divinyl compound (b1) described later, so it becomes easy to obtain a polymaleimide compound (A) having a uniform chemical structure or chain length, and as a result, a polymaleimide compound (A) having low hygroscopicity and low dielectric loss tangent when cured can be provided.

Hereinafter, after explaining the constituent components of the reaction raw material (1) of the polymaleimide compound (A), namely, an aromatic amine compound (a) having one or more but no more than three alkyl groups, an aromatic divinyl compound (b1) having two vinyl groups, an aromatic monovinyl compound (b2) having one vinyl group which may be an optional component, and maleic anhydride, other preferred forms of the polymaleimide compound (A) and a method for producing the polymaleimide compound (A) are explained.

＜＜Aromatic amine compound (a)＞＞ The aromatic amine compound (a) in the present embodiment has an aromatic ring bonded to an amine group ( _-NH2 or a substituted amine group), and one or more and three or less alkyl groups are bonded to the aromatic ring. Therefore, the aromatic amine compound (a) may be an amine compound. In addition, the aromatic ring forming the central structure of the aromatic amine compound (a) is preferably a monocyclic type, including an aromatic hydrocarbon ring and an aromatic heterocyclic ring. As the aromatic hydrocarbon ring, a benzene ring is preferred. As the 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 the present embodiment has an aromatic ring having no substituted amine group and to which -NH ₂ is bonded, and more preferably, one or more and no more than three alkyl groups are bonded to the aromatic ring.

In the aromatic amine compound (a) of the present embodiment, as the alkyl group replacing one or more and three or less hydrogen atoms of the aromatic ring of the aromatic amine compound (a), there can be listed 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 aforementioned alkyl group can be any of a linear type, a branched type, or a cyclic type. For example, there can be listed: a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a dibutyl group, a tertiary butyl group, etc. The smaller the molecular weight of the aforementioned alkyl group, the more significant the effect (low dimensional change rate) achieved by the present invention. In addition, the higher the molecular weight of the aforementioned alkyl group, the more significant the effect (low water absorption) achieved by the present invention.

The upper limit of the number of alkyl groups bonded to the aromatic ring having an amine group (including _-NH2 and substituted amine groups) in the aromatic amine compound (a) is a number obtained by subtracting 3 from the number of substitutable ring-constituting atoms in the unsubstituted aromatic ring, from the viewpoint that the aromatic ring has an amine group (including _-NH2 and substituted amine groups) and two bonds are used for polymerization. For example, when the aromatic ring is a benzene ring, the number of the alkyl groups is 3 or less. In addition, by setting the number of alkyl groups substituted on the aromatic ring of the aromatic amine compound (a) to 2 or more, it is easy to control the reaction site with the aromatic divinyl compound (b1) described later, and thus it is easy to obtain a polymaleimide compound (A) having a uniform chemical structure or chain length. As a result, the cured product of the polymaleimide compound (A) tends to exhibit low moisture absorption and excellent high-frequency electrical properties.

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 form of the aromatic amine compound (a) is described. In this embodiment, among the carbon atoms in the benzene ring constituting the aromatic amine compound (a), the carbon atom having the largest HOMO electron density (Hückel coefficient) is preferably unsubstituted (or substituted with a hydrogen atom). This makes it easy to control the _ArSE reaction and molecular design caused by the cationoid reagent formed by the aromatic divinyl compound (b1) described later. To explain in more detail, among the carbon atoms in the benzene ring constituting the aromatic amine compound (a), if the carbon atom having the largest HOMO electron density (Huckel coefficient) is unsubstituted, the carbon cation of the aromatic divinyl compound (b1) which is a cationic reagent is easily reacted with respect to the carbon atom having the largest HOMO electron density. Therefore, by controlling the number and position of the alkyl groups bonded to the carbon atom of the benzene ring, the bonding site or the number of bonds with the aromatic divinyl compound (b1) can be adjusted. Therefore, it is estimated that the chemical structure or molecular chain length of the obtained polymaleimide compound (A) becomes easy to design. For example, when the aromatic amine compound (a) has an aniline skeleton having one benzene ring and one amino group, at least one carbon atom at the 2-position, 4-position and 6-position of the aniline core is preferably substituted with a hydrogen atom. Thereby, at least one carbon atom at the 2-position, 4-position and 6-position of the aniline core, which has a high electron density of the ortho- and para-positions, becomes easy to attack by the cationic reagent formed by the aromatic divinyl compound (b1) described later. In particular, when an aromatic amine compound (a) having an aniline core substituted with an alkyl group at a specific position is used, the bonding site with the aromatic divinyl compound (b1) can be roughly controlled, so that it becomes easy to obtain a polymaleimide compound (A) with a uniform chemical structure or chain length. For example, when 2,6-dialkylamine is used as the aromatic amine compound (a), it is considered that a large amount of a polymaleimide compound (A) bonded to the aromatic divinyl compound (b1) at the 4-position can be obtained.

Specific examples of the aromatic amine compound (a) of the present embodiment include 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-diisopropylaniline), ethylmethylaniline (e.g., 2,3-, 2,4-, 2,6-, 3,4-diisopropylaniline or 3,5-diisopropylaniline), The aniline may be ethyl methyl aniline, wherein one of the 2, 4, 3, 5 positions is a methyl group and the other is an ethyl group, cyclobutyl aniline, cyclopentyl aniline, cyclohexyl aniline, o, m or p-toluidine, o, m or p-ethyl aniline, o, m or p-isopropyl aniline, o, m or p-propyl aniline, o, m or p-butyl aniline, methyl isopropyl aniline (e.g., methyl isopropyl aniline, wherein one of the 2, 3, 2, 4, 2, 6, 3, 4 or 3, 5 positions is a methyl group and the other is an isopropyl group), or ethyl butyl aniline (e.g., ethyl butyl aniline, wherein one of the 2, 3, 2, 4, 2, 6, 3, 4 or 3, 5 positions is an ethyl group and the other is a butyl group). The butyl group mentioned above includes normal butyl, tertiary butyl and secondary butyl. In addition, the aromatic amine compound (a) in this embodiment may be used alone or in combination of two or more kinds.

For example, in the case of N-phenylmaleimide, in the case of a chemical structure in which the maleimide group is directly bonded to the unsubstituted benzene ring, the benzene ring and the five-membered ring of maleimide are arranged on the same plane and are stable, so it becomes easy to stack (stacking), and it will show high crystallinity. Therefore, it becomes the cause of poor solvent solubility. In contrast, in the case of the present disclosure, for example: like 2,6-dimethylaniline, in the case of having an alkyl group (for example, methyl) as a substituent to the benzene ring, due to the stereo hindrance of the methyl group, the benzene ring and the five-membered ring of maleimide adopt a staggered conformation, becoming difficult to stack, so that the crystallinity is reduced, the solvent solubility is improved, and it becomes a better state. However, if the stereo hindrance is too large, the reactivity in the synthesis of maleimide may be hindered. Therefore, it is preferable to use an aromatic amine compound (a) having an alkyl group having 1 to 6 carbon atoms.

The aromatic amine compound (a) required as the reaction raw material (1) in the present embodiment can be represented by the following general formula (a), for example. (In the above general formula (a), R ^1a represents an alkyl group, and ^pa represents an integer of 1 to 3. Multiple R ^1a may be the same or different.)

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 the alkyl group having 1 to 6 carbon atoms and the alkyl group having 1 to 3 carbon atoms are the same as those described above. In the above general formula (a), p ^a is preferably 1 or 2. In addition, when R ^1a exists in plural numbers, they may be the same alkyl groups or different alkyl groups. In addition, in the present embodiment, the aromatic amine compound (a) represented by the above general formula (a) may be used alone or in combination of two or more.

<<Aromatic divinyl compound (b1)>> 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 referred to as vinyl) as substituents on the aromatic ring and can react with the aromatic amine compound (a). In this embodiment, a mixture of the aromatic divinyl compound (b1) and the aromatic monovinyl compound (b2) is preferably contained in the reaction raw material (1). Examples of the aromatic divinyl compound (b1) include divinylbenzene, divinylbiphenyl, divinylnaphthalene, and various compounds in which the aromatic rings of these are substituted with one or more substituents such as an alkyl group, alkoxy group or alkylthio group having 1 to 10 carbon atoms; an aryl group, aryloxy group 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 hydroxyl group. The preferred form of the substituent is the same as ^R2 in the general formula (1). The alkyl group may be a linear type or a branched type. From the viewpoint of exhibiting a high heat resistance effect, the number of carbon atoms of the alkyl group or alkoxy group is preferably 1 to 4. Specifically, the alkyl group may include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a tertiary butyl group, an isobutyl group, etc. The alkoxy group may include, for example, a methoxy group, an ethoxy group, a propoxy group, a butoxy group, etc. The halogen atom may include a fluorine atom, a chlorine atom, a bromine atom, etc.

The aromatic divinyl compound (b1) as the reaction material (1) of the polymaleimide compound (A) disclosed herein is preferably represented by the following formula (b1). (In the above general formula (b1), ^R2b each independently represents an alkyl group, alkoxy group or alkylthio group having 1 to 10 carbon atoms; an aryl group, aryloxy group 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 an alkyl group, and ^q1b represents an integer of 0 to 4. In addition, when ^q1b is an integer of 2 or more, the plural ^R2b groups may be the same or different from each other.)

R ^2b in the above formula (b1) may correspond to R ² in the general formula (1). Therefore, R ^2b in the above general formula (b1) is the same as in the general formula (1), and each 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, and more preferably represents an alkyl group having 1 to 10 carbon atoms, and further preferably represents an alkyl group having 1 to 6 carbon atoms. In the above general formula (b1), q ^1b is preferably 0 to 2. In addition, when q ^1b is 2 or more, the plural R ^b1s may be the same group or different groups.

Specific examples of the aromatic divinyl compound (b1) of the present embodiment include 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, 1,4-divinyl-2,5-dibutylbenzene, Divinylbenzenes such as methoxybenzene and compounds containing derivatives thereof, and divinylnaphthalenes such as 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 containing derivatives thereof, but are not limited thereto. In addition, the aromatic divinyl compound (b1) in this embodiment may be used alone or in combination of two or more. In particular, from the viewpoint of fluidity, the aromatic divinyl compound (b1) is preferably divinylbenzene and a compound having a substituent on its aromatic ring, and more preferably divinylbenzene. Furthermore, in this embodiment, the substitution position of the vinyl group of divinylbenzene is not particularly limited, but preferably the meta-position is the main component. The content of the meta-position in divinylbenzene is preferably 40% by mass or more, and more preferably 50% by mass or more, relative to the total amount of divinylbenzene. In this embodiment, relative to the total amount (100% by mass) of the polymaleimide compound (A), the structural unit of the aromatic divinyl compound (b1) preferably contains 10 to 90% by mass, and more preferably 20 to 90% by mass. The structural unit of the aromatic divinyl compound (b1) mentioned above refers to the group obtained by removing two hydrogen atoms (a total of four hydrogen atoms) from two vinyl groups of the aromatic divinyl compound (b1).

＜＜Aromatic monovinyl compound (b2)＞＞ The polymaleimide compound (A) in this embodiment may further use other compounds as reaction raw materials in addition to the aromatic amine compound (a), the aromatic divinyl compound (b1) and maleic anhydride. As the other compound, for example, an aromatic monovinyl compound (b2) having one vinyl group may be listed. That is, in the embodiment, it is preferred to use the aromatic amine compound (a), the aromatic divinyl compound (b1), the aromatic monovinyl compound (b2) and maleic anhydride as the reaction raw materials (1). The polymaleimide compound (A) of this embodiment uses an aromatic monovinyl compound (b2) in addition to the aromatic amine compound (a), the aromatic divinyl compound (b1) and maleic anhydride as its reaction raw materials, so that the cured product of the polymaleimide compound (A) obtained in the end is excellent in terms of low dielectric loss factor, which is preferred. In addition, since the aromatic monovinyl compound (b2) also generates carbon cations like the aromatic divinyl compound (b1), it is easy to react with the carbon atom with the largest HOMO electron density (Huckel coefficient) among the carbon atoms in the aromatic hydrocarbon ring constituting the aromatic amine compound (a).

The aromatic monovinyl compound (b2) in the present embodiment includes, for example, vinylbenzene (styrene), vinylbiphenyl, vinylnaphthalene, and various compounds substituted on the aromatic rings of these with 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 alkyl groups. The aforementioned alkyl group may be either a straight chain type or a branched type, and may have an unsaturated bond in the structure. Among them, when low hygroscopicity is important, the aforementioned alkyl group or the aforementioned alkoxy group preferably has 1 to 4 carbon atoms. As the aforementioned alkyl group, specifically, methyl, ethyl, propyl, isopropyl, butyl, tertiary butyl, isobutyl, etc. can be listed. Examples of the alkoxy group include methoxy, ethoxy, propoxy, butoxy, etc. Examples of the halogen atom include fluorine, chlorine, and bromine.

The aromatic monovinyl compound (b2) that can be used as the reaction material (1) of the polymaleimide compound (A) disclosed herein can be represented by the following general formula (b2). (In the above general formula (b2), R ^9b each independently represents an alkyl group, alkoxy group or alkylthio group having 1 to 10 carbon atoms; an aryl group, aryloxy group 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 an alkyl group, and t ^1b represents an integer of 0 to 5. In addition, when t ^1b is an integer of 2 or more, the plural R ^9b may be the same or different from each other.)

R ^9b in the above formula (b2) may correspond to R ⁹ in the general formula (x). Therefore, R ^9b in the above general formula (b1) is the same as the general formula (x), and each 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, and more preferably represents an alkyl group having 1 to 10 carbon atoms, and further preferably represents an alkyl group having 1 to 6 carbon atoms. In the above general formula (b1), t ^1b is preferably 1 to 4. In addition, when t ^1b is 2 or more, the plural R ^9b may be the same group or different groups.

Specific examples of the aromatic monovinyl compound (b2) of this embodiment include: vinylbenzenes such as styrene, fluorostyrene, vinylchlorotoluene, alkylvinylbenzenes (o-, m-, p-methylstyrene, o-, m-, p-ethylvinylbenzene), o-, m-, p-(chloromethyl)styrene and compounds containing derivatives thereof; biphenyl compounds such as 4-vinylbiphenyl, 4-vinyl-p-terphenyl and compounds containing derivatives thereof; and vinylnaphthalenes such as 1-vinylnaphthalene, 2-vinylnaphthalene and compounds containing derivatives thereof, but are not limited thereto. In particular, from the perspective of raw material acquisition, alkylvinylbenzenes and compounds having substituents on their aromatic rings are preferred, and ethylvinylbenzene is more preferred. In addition, the substitution positions of the vinyl and ethyl groups of ethylvinylbenzene are not particularly limited, but preferably the meta-form is the main component, and the content of the meta-form in ethylvinylbenzene is preferably 40% by mass or more, and further preferably 50% by mass or more relative to the total amount of ethylvinylbenzene.

When an aromatic monovinyl compound (b2) is used as the reaction raw material (1) of the polymaleimide compound (A) in this embodiment, the molar ratio ((b1)/(b2)) of the aromatic divinyl compound (b1) to the aromatic monovinyl compound (b2) in the aforementioned reaction raw material (1) is preferably 99/1 to 50/50, and more preferably 98/2 to 70/30. In this embodiment, the structural unit of the aromatic monovinyl compound (b2) preferably contains 0 to 40% by mass, and more preferably contains 0 to 30% by mass, relative to the total amount (100% by mass) of the polymaleimide compound (A). The structural unit of the aromatic monovinyl compound (b2) mentioned above refers to a group obtained by removing two hydrogen atoms from one vinyl group of the aromatic monovinyl compound (b2).

-Maleic Anhydride- In the present embodiment, maleic anhydride is an essential component of the reaction raw material (1) of the polymaleimide compound (A), and is used for maleimidizing the amine groups (including _-NH2 and substituted amine groups) derived from the aromatic amine compound (a) as described in the column of the production method of the polymaleimide compound (A) described below.

<Preferred form of polymaleimide compound (A)> Below, the suitable form of the polymaleimide compound (A) disclosed in the present invention is described by taking the case where each aromatic ring is a benzene ring as an example. The following chemical structure is used to illustrate the present invention by way of example, and the scope of the present invention is not limited to the following chemical structure.

In this embodiment, the polymaleimide compound (A) is preferably represented by the following general formula (2). (In the above general formula (2), ^R1 is independently an alkyl group, ^R2 is 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, ^R3 , ^R4 , ^R5 , and ^R6 are independently a hydrogen atom or a methyl group, and one of ^R3 and ^R4 is a hydrogen atom and the other is a methyl group, and one of ^R5 and ^R6 is a hydrogen atom and the other is a methyl group; ^X1 is a substituent represented by the following general formula (x); (In the general formula (x), ^R7 and ^R8 each independently represent a hydrogen atom or a methyl group, and one of ^R7 and ^R8 is a hydrogen atom and the other is a methyl group, ^R9 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, and t represents an integer of 0 to 4.) ^M21 represents a hydrogen atom or a group represented by the following general formula (i), ^M22 represents a hydrogen atom, a group represented by the following general formula (ii), or a group represented by the following general formula (iii); [In the above general formula (i), R ⁹ 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 ⁷ and R ⁸ each independently represent a hydrogen atom or a methyl group, and one of R ⁷ and R ⁸ is a hydrogen atom and the other is a methyl group, t represents an integer of 0 to 4, and * represents a bond with other atoms. In addition, when t is an integer of 2 or more, the plural R ^9s may be the same or different from each other.] [In the above general formula (ii), R ¹ⁱⁱ represents an alkyl group, and p ⁱⁱ represents an integer of 0 to 4. In addition, when p ⁱⁱ is an integer of 2 or more, the plural R ¹ⁱⁱ may be the same or different from each other. In the above general formula (iii), R ¹ⁱⁱⁱ represents an alkyl group, R ⁹ 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 ⁷ and R ⁸ each independently represent a hydrogen atom or a methyl group, and one of R ⁷ and R ⁸ is a hydrogen atom and the other is a methyl group, p ⁱⁱⁱ represents an integer of 0 to 3, t represents an integer of 0 to 4, r ¹ⁱⁱⁱ is the average value of the number of substitutions per benzene ring bonded to X ¹ , and represents a number of 1 to 4, and * represents a bond to other atoms. In addition, when ^piii is an integer greater than or equal to 2, a plurality of ^R1iii may be the same or different from each other, and when t is an integer greater than or equal to 2, a plurality of ^R9 may be the same or different from each other.] r is the average value of the number of substitutions of ^X1 per benzene ring to which X1 is ^bonded , and represents a number from 0 to 4, 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.) In the above general formula (2), when p is an integer greater than or equal to 2, a plurality of ^R1 may be the same or different from each other, when q is an integer greater than or equal to 2, a plurality of ^R2 may be the same or different from each other, and when t is an integer greater than or equal to 2, a plurality of ^R9 may be the same or different from each other. In addition, the preferred forms of R ¹ to R ⁹ , X ¹ , p, q, r, t and k in the general formula (2) are the same as those in the general formula (1). Furthermore, the general formula (i) corresponds to the general formula (x), R ¹ⁱⁱ in the general formula (ii) corresponds to R ¹ in the general formula (1), and R ¹ⁱⁱⁱ in the general formula (iii) corresponds to R ¹ in the general formula (1).

The number average molecular weight (Mn) of the polymaleimide compound (A) 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 polymaleimide compound (A) is preferably in the range of 400 to 500,000, more preferably in the range of 450 to 400,000. From the viewpoint of excellent low dielectric constant and low dielectric loss factor, the molecular weight distribution (weight average molecular weight (Mw)/number average molecular weight (Mn)) of the polymaleimide compound (A) disclosed herein is preferably in the range of 1.001 to 500, more preferably in the range of 1.001 to 400, as measured by gel permeation chromatography (GPC). In addition, according to the GPC graph obtained by GPC measurement, the molecular weight distribution spans a wide range. When there are many high molecular weight components, the proportion of high molecular weight components that contribute to flexibility increases. Therefore, compared with the cured product using the conventional maleimide, a cured product with suppressed brittleness and excellent flexibility and softness can be obtained, which is a better state. In addition, 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 polymaleimide compound (A) of this embodiment are measured using gel permeation chromatography (hereinafter referred to as "GPC") under the measurement conditions described in the embodiments described below.

When the polymaleimide compound (A) in the present embodiment contains an indane skeleton (or a structural unit having an indane skeleton) represented by the following general formula (3), the ratio of the indane skeleton relative to the total amount (100% by mass) of the polymaleimide compound (A) is preferably 10% by mass or less, more preferably 5% by mass or less, further preferably 3% by mass or less, further preferably 2% by mass or less, and particularly preferably 0.9% by mass or less. (In the above general formula (3), R ³¹ , R ³² and R ³³ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R ³⁴ each independently represents an alkyl group, alkoxy group or alkylthio group having 1 to 10 carbon atoms; an aryl group, aryloxy group 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 an alkyl group, q ³ represents an integer of 0 to 3, and when q ³ is an integer greater than 2, the multiple R ^34s may be the same or different from each other. In addition, * represents a bond with other atoms.) In the above general formula (3), R ³⁴ each independently represents an alkyl group having 1 to 6 carbon atoms, and more preferably represents an alkyl group having 1 to 3 carbon atoms. In the general formula (3), R ³¹ , R ³² and R ³³ are preferably hydrogen atoms or methyl groups. In the curable composition of the present embodiment, the polymaleimide compound (A) is preferably contained in an amount of 60 mass % to 95 mass %, more preferably 70 mass % to 93 mass %, and most preferably 80 mass % to 90 mass %. When the content of the polymaleimide compound (A) is in the range of 60 mass % to 95 mass %, it is preferred from the viewpoint of heat resistance.

<Method for producing polymaleimide compound (A)> The following is a description of the method for producing the polymaleimide compound (A) disclosed herein. The method for producing the polymaleimide compound (A) of 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 the reaction raw materials (1), or as long as the structural unit represented by the above general formula (1) is present, it can be produced in any manner. As an example of the method for producing the polymaleimide compound (A) disclosed herein, for example, a method comprising the following steps (1) and (2) can be cited. Step (1): reacting the aromatic amine compound (a) as the reaction raw material (2) with the aromatic divinyl compound (b1) to obtain the intermediate amine compound (c) in the present embodiment; Step (2): reacting the intermediate amine compound (c) obtained in the above step (1) as the reaction raw material (3) with maleic anhydride to obtain the polymaleimide compound (A) disclosed herein. Specifically, the method for producing the polymaleimide compound (A) of the present embodiment preferably comprises: a step (1) of reacting an aromatic amine compound (a) with an aromatic divinyl compound (b1) under a solid acid catalyst (also referred to as a crosslinking step), and a step (2) of condensing the intermediate amine compound (c) generated by the aforementioned step (1) with maleic anhydride (also referred to as a condensation step). The following describes the steps of the method for producing the polymaleimide compound (A) disclosed herein in order.

＜＜Step (1): Production step of intermediate amine compound (c)＞＞ The following is a description of the production step of the intermediate amine compound (c) in this embodiment. Step (1) in this embodiment is not particularly limited, but is, for example, a step of reacting the above-mentioned aromatic amine compound (a), the above-mentioned aromatic divinyl compound (b1) (for example, divinylbenzene), and other compounds such as an aromatic monovinyl compound (b2) (for example, ethylvinylbenzene) as required in the presence of an acid catalyst. In this way, the intermediate amine compound (c) can be generated.

As the blending ratio of the aromatic amine compound (a) and the aromatic divinyl compound (b1), the molar ratio of the aromatic divinyl compound (b1) is preferably 0.1 to 10 moles, and more preferably 0.2 to 3 moles, relative to 1 mole of the aromatic amine compound (a). In addition, when the aromatic monovinyl compound (b2) is used in combination, the total molar ratio of the aromatic divinyl compound (b1) and the aromatic monovinyl compound (b2) is preferably 0.1 to 10 moles, and more preferably 0.2 to 3 moles, relative to 1 mole of the aromatic amine compound (a). In addition, as a specific method for implementing the above reaction, generally all the raw materials are charged at once and reacted directly at a specified temperature, or an aromatic amine compound (a) and an acid catalyst are charged, and an aromatic divinyl compound (b1) and other compounds (for example, an aromatic monovinyl compound (b2)) are dripped while maintaining a specified temperature, and reacted simultaneously. At this time, the dripping time is usually 0.1 to 12 hours, preferably less than 6 hours. After the reaction, when a solvent is used, the solvent and unreacted products are distilled off as needed to obtain the aforementioned intermediate amine compound (c). When a solvent is not used, the target intermediate amine compound (c) can be obtained by distilling off the unreacted products.

The acid catalyst used in step (1) of the present embodiment may include, for example, 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 resins, and polyacid salts. However, from the perspective of handling, solid acids that can be easily removed by filtering after the reaction are preferred. When other acids are used, neutralization with alkali and washing with water are preferably performed after the reaction. The amount of the acid catalyst mixed is in the range of 1 to 100 parts by mass relative to the total amount of 100 parts by mass of the raw materials (aromatic divinyl compound (b1) or a mixture of aromatic divinyl compound (b1) and aromatic monovinyl compound (b2), and aromatic amine compound (a)). However, from the perspective of handling and economy, it is preferably 1 to 60 parts by mass. The reaction temperature is usually in the range of 100 to 270°C, but in order to suppress the formation of isomers and avoid side reactions such as thermal decomposition, it is preferably 100 to 220°C.

In step (1) of the present embodiment, the reaction time of the mixture of the aromatic divinyl compound (b1) or the aromatic divinyl compound (b1) and the aromatic monovinyl compound (b2) with the aromatic amine compound (a), i.e., the time of the crosslinking reaction, is usually within the range of 1 to 48 hours in total, preferably within the range of 1 to 30 hours in total, under the aforementioned reaction temperature conditions, because if the reaction time is too short, the reaction will not proceed completely, and if the reaction time is too long, side reactions such as thermal decomposition of the product will occur. In the method for producing the intermediate amine compound (c) in the present embodiment, since aniline or its derivatives also serve as solvents, it is not necessary to use other solvents, but solvents may also be used. For example, when divinylbenzene is used as a raw material for the reaction, the following method can be adopted: using a solvent capable of azeotropic dehydration such as toluene, xylene or chlorobenzene, and if necessary, azeotropically dehydrating the water contained in the catalyst, etc., first distilling off the solvent, and then reacting within the above reaction temperature range.

The intermediate amine compound (c) obtained in the above step (1) is preferably represented by the following general formula (4). (In the above general formula (4), ^R1 is independently an alkyl group, ^R2 is independently an alkyl group, an alkoxy group or an alkylthio group having 1 to 10 carbon atoms; an aryl group, an aryloxy group or an arylthio group having 6 to 10 carbon atoms; a cycloalkyl group having 3 to 10 carbon atoms; a halogen atom; a hydroxyl group or an alkyl group; ^R3 , ^R4 , ^R5 and ^R6 are independently a hydrogen atom or a methyl group, and one of ^R3 and ^R4 is a hydrogen atom and the other is a methyl group, and one of ^R5 and ^R6 is a hydrogen atom and the other is a methyl group; ^X1 is a substituent represented by the following general formula (x); (In the general formula (x), ^R7 and ^R8 each independently represent a hydrogen atom or a methyl group, and one of ^R7 and ^R8 is a hydrogen atom and the other is a methyl group, ^R9 represents ^an alkyl group, and t represents an integer from 0 to 4.) r is the average value of the number of substitutions of ^X1 per benzene ring bonded to X1, and represents a number from 0 to 4, 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.)

In the above general formula (4), when p is an integer greater than 2, plural R ^1s may be the same or different from each other. When q is an integer greater than 2, plural R ^2s may be the same or different from each other. When t is an integer greater than 2, plural R ^9s may be the same or different from each other.

In addition, the preferred forms of R ¹ to R ⁹ , X ¹ , p, q, r, t and k in the general formula (4) are the same as those in the general formula (1). In addition, as another preferred form of the intermediate amine compound (c) obtained through the step (1), there can be cited a structure in which the N-substituted maleimide group in the general formula (2) which is also a preferred form of the polymaleimide compound (A) is replaced by an amino group (including -NH ₂ and substituted amino groups).

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. In addition, the amine equivalent of the intermediate amine compound (c) in this specification is measured by the neutralization titration method specified in JIS K 0070 (1992).

＜＜Step (2): Maleimidation＞＞ Step (2) in this embodiment is a step of reacting the intermediate amine compound (c) obtained in step (1) with maleic anhydride. Since the amine group (including _-NH2 and substituted amine group) of the intermediate amine compound (c) can be substituted into a chemical structure of an N-substituted maleimide ring by maleimidation, the polymaleimide compound (A) disclosed herein can be obtained. In this embodiment, the intermediate amine compound (c) represented by the above general formula (4) obtained in step (1) is put 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 reducing the pressure to obtain the target polymaleimide compound (A). In addition, a dehydrating agent may be used during the reaction as needed.

The organic solvent used in step (2) of the present embodiment includes ketones such as acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, cyclohexanone, acetophenone, etc., aprotic solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone, acetonitrile, cyclobutane sulfone, cyclic ethers such as dioxane, tetrahydrofuran, esters such as ethyl acetate, butyl acetate, etc., and aromatic solvents such as benzene, toluene, xylene, etc. These solvents may be used alone or in combination.

In step (2) of the present embodiment, the mixing ratio of the intermediate amine compound (c) and maleic anhydride is preferably in the range of 1 to 5 equivalents of maleic anhydride relative to the amino group equivalent of the intermediate amine compound (c), more preferably 1 to 3 equivalents, and the reaction is preferably carried out in an organic solvent at a mass ratio of 0.1 to 10, preferably 0.2 to 5, relative to the total amount of the intermediate amine compound (c) and maleic anhydride.

The catalyst that can be used in step (2) of this embodiment includes: inorganic salts such as acetates, chlorides, bromides, sulfates, nitrates, etc. of nickel, cobalt, sodium, calcium, iron, lithium, manganese, etc.; inorganic acids such as phosphoric acid, hydrochloric acid, sulfuric acid; organic acids such as oxalic acid, benzenesulfonic acid, toluenesulfonic acid, methanesulfonic acid, fluoromethanesulfonic acid, etc.; solid acids such as activated clay, acid clay, silica alumina, zeolite, strongly acidic ion exchange resins, polyacid salts, etc., and toluenesulfonic acid is particularly preferred.

As the dehydrating agent used in step (2) of the present embodiment, there can be listed lower aliphatic carboxylic acid anhydrides such as acetic anhydride, propionic anhydride, butyric anhydride, oxides such as phosphorus pentoxide, calcium oxide, barium oxide, inorganic acids such as sulfuric acid, porous ceramics such as molecular sieves, etc., and acetic anhydride is preferably used. There is no particular limitation on the amount of the catalyst and dehydrating agent used in step (2) of the present embodiment, but usually, the catalyst can be used in an amount of 0.0001 to 1.0 mol, preferably 0.01 to 0.3 mol, and the dehydrating agent can be used in an amount of 1 to 3 mol, preferably 1 to 1.5 mol, relative to 1 equivalent of the amino group ( _-NH2 ) of the intermediate amine compound (c). In step (2) of the present embodiment, as the reaction conditions for maleimidation, the intermediate amine compound (c) and maleic anhydride may be added 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, and then the 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.

(Amine compound (B)) The curable composition of the present embodiment contains an amine compound (B). Since the combination of the amine compound (B) and the polymaleimide compound (A) can help the low-temperature curing as a whole and show excellent molding processability, it can be used as a molding material for structural materials and is useful. In addition, by reacting with the polymaleimide compound (A), it can act as a curing agent and produce three-dimensional crosslinking, so that a cured product with excellent heat resistance can be obtained, which becomes a better state. As the amine compound (B) in the present embodiment, there can be listed compounds having primary to tertiary amine groups, preferably hydrocarbons having 1 or more carbon atoms, preferably 3 to 25 carbon atoms, and hydrocarbon compounds having 2 or more primary amine groups in one molecule are more preferred. As the amine compound (B), an aliphatic amine compound or an aromatic amine compound is preferred, and an aliphatic primary diamine compound or an aromatic primary diamine compound is more preferred. In addition, the aromatic amine compound includes an aromatic heterocyclic compound, and the aliphatic amine compound includes an alicyclic aliphatic compound. Specific examples of the aliphatic amine compound of the present embodiment include: ethylenediamine, diethylenetriamine, hexamethylenediamine, triethylenetetramine, isophoronediamine, guanidine derivatives, guanamine derivatives, 1,3-diaminomethylcyclohexane, The aliphatic amine compound may be used alone or in combination of two or more. Specific examples of the aromatic amine compound of the present embodiment include o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 3-methyl-1,4-diaminobenzene, m-xylenediamine, p-xylenediamine, diethyltoluenediamine, 2,5-dimethyl-1,4-diaminobenzene, diaminodiphenylmethane (e.g., 4,4'-diaminodiphenylmethane), diaminodiphenylethane, 4,4'-diamino-3,3'-dimethyl-diphenylmethane, 4,4'-diamino-3,3'-diethyl-diphenylmethane, diaminodiphenyl ether (e.g., 4,4'-diaminodiphenyl ether), diaminodiphenyl sulfone (e.g., 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone), 4,4'-diaminodiphenyl ketone, diaminodiphenyl ether ..., 3,3'-diaminodiphenyl sulfone), 4,4'-diaminodiphenyl ketone, diaminodiphenyl ether (e.g., 4,4'-diaminodi Aniline, 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dihydroxybenzidine, 2,2-bis(3-amino-4-hydroxyphenyl)propane, 3,3-dimethyl-5,5-diethyl-4,4-diphenylmethanediamine, 2,2-bis(4-aminophenyl)propane, 2,2-bis(4-(4-aminophenyl)propane The aromatic amine compound may be used alone or in combination of two or more. Among the aromatic amine compounds, m-phenylenediamine, p-phenylenediamine, 3-methyl-1,4-diaminobenzene or 2,5-dimethyl-1,4-diaminobenzene is more preferred when mechanical properties during curing are important. On the other hand, when heat resistance is important, 4,4'-diaminodiphenylmethane, 3,3'-dimethyl-4,4'-diaminobiphenyl, 4,4'-diamino-3,3'-dimethyl-diphenylmethane, 4,4'-diamino-3,3'-diethyl-diphenylmethane, 4,4'-bis(4-aminophenoxy)biphenyl, or 2,2-bis(4-(4-aminophenoxy)phenyl)propane is more preferred. Moreover, when solubility in solvents or handling properties are important, 4,4'-diaminodiphenylmethane, 3,3'-dimethyl-4,4'-diaminobiphenyl, 4,4'-diamino-3,3'-diethyl-diphenylmethane, and 2,2-bis(4-(4-aminophenoxy)phenyl)propane are more preferred. Furthermore, when low dielectric properties are important, 4,4'-diamino-3,3'-diethyl-diphenylmethane and 2,2-bis(4-(4-aminophenoxy)phenyl)propane are more preferred. In addition, as other amine compounds (B) other than the above-mentioned aliphatic amine compounds and the above-mentioned aromatic amine compounds, hydroxyammonium sulfate, _BF3 -amine complex, etc. can be listed. As the preferred amine compound (B) of this embodiment, when control of the curing reaction and formability are important, aromatic amine compounds are preferred. Since aliphatic amine compounds act as catalysts and tend to advance the curing reaction early, when formability is important, aromatic amine compounds are preferably used.

In the curable composition of the present embodiment, the amine compound (B) is preferably contained in an amount of 5 mass % to 50 mass % relative to the entire curable composition, more preferably in an amount of 7 mass % to 30 mass % and most preferably in an amount of 10 mass % to 20 mass %. When the content of the amine compound (B) is in the range of 10 mass % to 20 mass %, it is preferred from the viewpoint of heat resistance.

(Curing agent (C) other than amine compound (B)) The curing composition of this embodiment may also contain a curing agent (C) other than amine compound (B) within the range that does not impair the curing of the present invention. In addition, relative to the total amount of 100 mass% of the curing composition, the amount of the curing agent (C) is preferably 2 mass% to 20 mass%, and the most preferred amount is 5 mass% to 10 mass%. The content of the curing agent (C) in the range of 5 mass% to 10 mass% is preferred from the perspective of curability and low dielectric loss factor.

Examples of the curing agent (C) of this embodiment include cyanate compounds, amide compounds, anhydride compounds, phenol compounds, polyphenylene ether compounds, compounds having a substituent containing an unsaturated double bond, diene polymers, etc. These curing agents may be used alone or in combination of two or more.

Examples of the cyanate compounds include bisphenol A type cyanate resins, bisphenol F type cyanate resins, bisphenol E type cyanate resins, bisphenol S type cyanate resins, bisphenol thioether type cyanate resins, phenylene ether type cyanate resins, naphthylene ether type cyanate resins, biphenyl type cyanate resins, tetramethylbiphenyl type cyanate resins, polyhydroxynaphthalene type cyanate resins, phenol novolac type cyanate resins, cresol novolac type cyanate resins, triphenylmethane type cyanate resins, Cyanate resins, tetraphenylethane type cyanate resins, dicyclopentadiene-phenol addition reaction type cyanate resins, phenol aralkyl type cyanate resins, naphthol novolac type cyanate resins, naphthol aralkyl type cyanate resins, naphthol-phenol co-phenol novolac type cyanate resins, naphthol-cresol co-phenol novolac type cyanate resins, aromatic hydrocarbon formaldehyde resin-modified phenol resin type cyanate resins, biphenyl-modified novolac type cyanate resins, anthracene type cyanate resins, etc. These may be used alone or in combination of two or more.

Examples of the amide compounds include dicyandiamide and polyamide resins synthesized from a dimer of perilla oil acid and ethylenediamine.

Examples of the acid anhydride compounds include phthalic anhydride, trimellitic anhydride, pyrophthalic anhydride, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, hexahydrophthalic anhydride, and methylhexahydrophthalic anhydride.

Examples of the phenolic compounds include phenol novolac resins, cresol novolac resins, aromatic hydrocarbon formaldehyde resin-modified phenolic resins, dicyclopentadiene phenol addition resins, phenol aralkyl resins (XYLOK resins), polyvalent phenol novolac resins synthesized from polyvalent hydroxyl compounds and formaldehyde, such as resorcin novolac resins, and polyvalent phenol novolac resins. Varnish resin, naphthol aralkyl resin, trihydroxymethyl methane resin, tetraphenol ethane resin, naphthol phenol varnish resin, naphthol-phenol co-phenol varnish resin, naphthol-cresol co-phenol varnish resin, biphenyl modified phenol resin (a polyphenol compound formed by connecting a phenol nucleus with a di-methylene group), biphenyl modified naphthol resin (a polyphenol compound formed by connecting a phenol nucleus with a di-methylene group), aminotri Polyphenol compounds such as modified phenol resins (polyphenol compounds formed by linking phenol nuclei with melamine, benzoguanamine, etc.), alkoxy-containing aromatic ring-modified phenolic varnish resins (polyphenol compounds formed by linking phenol nuclei and alkoxy-containing aromatic rings with formaldehyde), etc.

The polyphenylene ether compound is preferably a compound having a structure represented by the following general formula (5) or (6).

In the above general formulae (5) and (6), ^Rd1 to ^Rd8 are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an alkenyl group having 1 to 5 carbon atoms, a cycloalkyl group having 3 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, a thioether group having 1 to 5 carbon atoms, an alkylcarbonyl group having 2 to 5 carbon atoms, an alkyloxycarbonyl group having 2 to 5 carbon atoms, an alkylcarbonyloxy group having 2 to 5 carbon atoms, an alkylsulfonyl group having 1 to 5 carbon atoms, etc. As the terminal structure of the structures of the above general formulae (5) and (6), there are those having a hydroxyl group or a group containing a reactive double bond, etc. In addition, v is an integer value of 1 to 30, and w and u are also integer values of 1 to 30.

The thioether group having 1 to 5 carbon atoms is not particularly limited, and examples thereof include methylthio, ethylthio, propylthio, isopropylthio, butylthio, and pentylthio.

The alkylcarbonyl group having 2 to 5 carbon atoms is not particularly limited, and examples thereof include methylcarbonyl, ethylcarbonyl, propylcarbonyl, isopropylcarbonyl, and butylcarbonyl.

The alkyloxycarbonyl group having 2 to 5 carbon atoms is not particularly limited, and examples thereof include methyloxycarbonyl, ethyloxycarbonyl, propyloxycarbonyl, isopropyloxycarbonyl, and butyloxycarbonyl.

The alkylcarbonyloxy group having 2 to 5 carbon atoms is not particularly limited, and examples thereof include methylcarbonyloxy, ethylcarbonyloxy, propylcarbonyloxy, isopropylcarbonyloxy, and butylcarbonyloxy.

The alkylsulfonyl group having 1 to 5 carbon atoms is not particularly limited, but examples thereof include methylsulfonyl, ethylsulfonyl, propylsulfonyl, isopropylsulfonyl, butylsulfonyl, and pentylsulfonyl.

In this embodiment, ^Rd1 to ^Rd8 in the general formulae (5) and (6) may be the same as or different from each other, and are preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a cycloalkyl group having 3 to 5 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, further preferably a hydrogen atom, a methyl group, or an ethyl group, and particularly preferably a hydrogen atom or a methyl group.

In the general formula (6), Y can be a divalent aromatic group derived from an aromatic compound having two phenolic hydroxyl groups. The aromatic compound having two phenolic hydroxyl groups is not particularly limited, but 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, tetramethylbisphenol A, etc. can be mentioned. Among these, hydroquinone, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 4,4'-biphenol, bisphenol A, bisphenol E, bisphenol F are preferred, and 4,4'-biphenol, bisphenol A, and tetramethylbisphenol A are more preferred. In addition, since the two phenolic hydroxyl groups of the aromatic compound having two phenolic hydroxyl groups will form a phenylene ether bond (two oxygen atoms bonded to Y), Y will become a divalent aromatic group derived from the aromatic compound having two phenolic hydroxyl groups. In other words, the group obtained by removing any two hydrogen atoms from the aromatic compound having two phenolic hydroxyl groups is regarded as a "divalent aromatic group derived from the aromatic compound having two phenolic hydroxyl groups".

The above-mentioned compound having a substituent containing an unsaturated double bond is not particularly limited as long as it has a substituent containing two or more unsaturated bonds in the molecule, but examples thereof include allyl, isopropenyl, 1-propenyl, acrylyl, methacryl, styryl, styrylmethyl, etc. as the above-mentioned substituent containing an unsaturated bond.

Examples of the diene polymer include non-modified diene polymers that are not modified by polar groups. Here, the polar group is a functional group that affects dielectric properties, and examples thereof include phenol groups, amino groups, and epoxy groups. The diene polymer is not particularly limited, and examples thereof include 1,2-polybutadiene and 1,4-polybutadiene.

As the diene polymer, a butadiene homopolymer and its derivatives in which 50% or more of the butadiene units in the polymer chain are 1,2-bonds may be used.

(Other resins (D)) In addition to the polymaleimide compound (A) and the amine compound (B), other resins (D) may be contained as long as the purpose of the present disclosure is not impaired. As the other resin (D), dimaleimides other than the aforementioned polymaleimide compound (A), allyl ether compounds, allyl amine compounds, triallyl cyanurate, alkenylphenol compounds, vinyl-containing polyolefin compounds, epoxy resins, phenol resins, active ester resins, polyphenylene ether resins, benzophenone resins, etc. may be appropriately blended. Resin, styrene maleic anhydride copolymer, polybutadiene and its modified products, polyacetal resin, polyvinyl alcohol resin, liquid crystal polymer, fluorine resin, polystyrene, polyethylene, polyimide resin, thermosetting polyimide resin, silicone, silicone oil, etc. In addition, since the curable composition of the present embodiment contains an amine compound (B), an epoxy resin can also be selected as the other resin (D). Thus, in the curable composition containing the polymaleimide compound (A), the amine compound (B) and the epoxy resin, since the amine compound (B) acts as a curing agent, the adhesion to copper is improved, which can be useful, for example, in the manufacture of circuit boards using copper foil.

The epoxy resin is not particularly limited, but examples thereof include phenol novolac epoxy resins, cresol novolac epoxy resins, α-naphthol novolac epoxy resins, β-naphthol novolac epoxy resins, bisphenol A novolac epoxy resins, biphenyl novolac epoxy resins, etc.; phenol aralkyl epoxy resins, naphthol aralkyl epoxy resins; Epoxy resins, aralkyl epoxy resins such as phenol biphenyl aralkyl epoxy resins; bisphenol type epoxy resins such as bisphenol A type epoxy resin, bisphenol AP type epoxy resin, bisphenol AF type epoxy resin, bisphenol B type epoxy resin, bisphenol BP type epoxy resin, bisphenol C type epoxy resin, bisphenol E type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, tetrabromobisphenol A type epoxy resin Biphenyl type epoxy resins, tetramethylbiphenyl type epoxy resins, epoxy resins having a biphenyl skeleton and a diglycidyloxybenzene skeleton, etc.; naphthalene type epoxy resins; binaphthol type epoxy resins; binaphthyl type epoxy resins; dicyclopentadiene type epoxy resins such as dicyclopentadiene phenol type epoxy resins; tetracyclopentadienyl diamino diphenylmethane type epoxy resins, tricyclopentadienyl-p-amine Epoxy resins such as epoxy resins of hydroxyphenol type, epoxy resins of epoxy resins of diaminodiphenyl sulfone, epoxy resins of epoxy resins of diglycidyl ester type, epoxy resins of epoxy resins of hexahydrophthalic anhydride, etc.; benzopyran type epoxy resins such as dibenzopyran, hexamethyldibenzopyran, 7-phenylhexamethyldibenzopyran, etc. These can be used alone or in combination of two or more. The content of other resins (D) 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, relative to 100% by mass of the total amount of the curable composition. If the content of other resins (D) is in the range of 5 mass% to 10 mass%, it is better from the perspective of heat resistance.

(Hardening accelerator) The curable composition of this embodiment can also be used in combination with a hardening accelerator as needed. Various hardening accelerators can be used as the aforementioned hardening accelerator, for example, the addition of polymerization initiators such as organic peroxides and azo compounds or alkaline catalysts such as phosphine compounds and tertiary amines is effective. Specific examples of the aforementioned hardening accelerator include benzoyl peroxide, diisopropylbenzene peroxide, azobisisobutylonitrile, triphenylphosphine, TPP-MK, TPP-K, triethylamine, imidazoles, etc. The hardening accelerator can be used alone or in combination of two or more. As for the blending amount of the hardening accelerator in this embodiment, it is preferably 0.05 to 5% by mass of the entire hardening resin composition.

(Additives) The curable composition of this embodiment can also be used with additives as needed. Examples of the aforementioned additives include silane coupling agents, mold release agents, pigments, emulsifiers, non-halogen flame retardants, inorganic fillers, flame retardants, solvents, etc. The content of the additive is preferably 1% by mass to 20% by mass, and the most preferred is 3% by mass to 10% by mass, relative to the total amount of the curable composition of 100% by mass.

As the flame retardant, there can be cited inorganic phosphorus flame retardants, organic phosphorus flame retardants, halogen flame retardants or non-halogen flame retardants. The curable composition of the present embodiment is preferably blended with a non-halogen flame retardant that does not substantially contain halogen atoms in order to exert flame retardancy within the scope of not impairing the purpose. As the non-halogen flame retardant, there can be cited, for example, phosphorus flame retardants, nitrogen flame retardants, silicone flame retardants, inorganic flame retardants, organic metal salt flame retardants, etc. These can be used alone or in combination.

The curable composition of the present embodiment may also be blended with an inorganic filler as needed. Examples of the aforementioned inorganic filler include fused silica, crystalline silica, alumina, silicon nitride, aluminum hydroxide, and the like. In the case where the blending amount of the aforementioned inorganic filler is particularly high, it is preferred to use fused silica. The aforementioned fused silica may be used in either a crushed or spherical form, but in order to increase the blending amount of the fused silica and suppress the increase in the melt viscosity of the molding material, it is preferred to mainly use spherical forms. In order to further increase the blending amount of spherical silica, it is preferred to appropriately adjust the particle size distribution of the spherical silica. In view of flame retardancy, a higher filling rate is preferred, and a filling rate of 30% by mass or more and 50% by mass or less relative to the total amount of the curable composition is particularly preferred. When the curable composition is used for the purpose of a conductive paste as described in detail below, a conductive filler such as silver powder or copper powder may be used.

In the curable composition of the present embodiment, the lower limit of the total content of the polymaleimide compound (A) and the amine compound (B) relative to the whole curable composition (100 mass%) is preferably 40 mass%, 42 mass%, 45 mass%, 47 mass%, 48 mass% or 50 mass%. In addition, the upper limit of the above-mentioned total content is preferably 100 mass%, 99 mass%, 98 mass% or 97 mass%. The above upper limit and the above lower limit can be arbitrarily combined. Therefore, for example, in the curable composition of the present embodiment, the total content of the polymaleimide compound (A) and the amine compound (B) is preferably 40% by mass or more and 100% by mass or less relative to the whole curable composition (100% by mass), the total content of the polymaleimide compound (A) and the amine compound (B) is more preferably 45% by mass or more and 100% by mass or less, and the total content of the polymaleimide compound (A) and the amine compound (B) is further preferably 50% by mass or more and 100% by mass or less. In the curable composition of the present embodiment, the lower limit of the total content of the polymaleimide compound (A), the amine compound (B) and the inorganic filler relative to the whole curable composition (100% by mass) is preferably 70% by mass, 73% by mass, 75% by mass, 77% by mass or 80% by mass. Furthermore, the upper limit of the above-mentioned total content is preferably 100 mass%, 99 mass%, 98 mass% or 97 mass%. The above-mentioned upper limit value and the above-mentioned lower limit value can be arbitrarily combined in the same manner as the range of the total content of the polymaleimide compound (A) and the amine compound (B). In the curable composition of this embodiment, the lower limit of the total content of the polymaleimide compound (A), the amine compound (B) and the additive is preferably 43 mass%, 45 mass%, 48 mass%, 50 mass% or 53 mass% relative to the whole curable composition (100 mass%). Furthermore, the upper limit of the above-mentioned total content is preferably 100 mass%, 99 mass%, 98 mass% or 97 mass%. The aforementioned upper limit value and the aforementioned lower limit value can be arbitrarily combined, as can the range of the total content of the polymaleimide compound (A) and the amine compound (B).

[Hardened product] The cured product disclosed herein is preferably obtained by the aforementioned curable composition. The aforementioned cured product can be obtained by subjecting the aforementioned curable composition to a curing reaction. The aforementioned curable composition is obtained by uniformly mixing the aforementioned components (e.g., curing agent, admixture), and can be easily made into a cured product by the same method as the known method. As the aforementioned cured product, there can be listed formed cured products such as laminated products, cast products, adhesive layers, coatings, and films. As for the aforementioned curing (thermal curing) reaction, it is easy to proceed even without a catalyst, but in the case of further accelerating the reaction, it is effective to add a polymerization initiator such as an organic peroxide or an azo compound, or an alkaline catalyst such as a phosphine compound or a tertiary amine. For example, there are benzoyl peroxide, diisopropylbenzene peroxide, azobis(isobutylene nitrile), triphenylphosphine, triethylamine, imidazoles, etc. The blending amount is preferably 0.05 to 5% by mass of the entire curable resin composition.

[Heat-resistant materials and electronic materials] The cured product obtained by the curable composition containing the polymaleimide compound (A) and the amine compound (B) disclosed herein has excellent low moisture absorption and low dielectric properties, and can be used in heat-resistant components or electronic components. In particular, it can be used in prepregs, circuit boards, semiconductor packaging materials, semiconductor devices, build-up films, build-up substrates, adhesives or resistor materials using conductive pastes, etc. In addition, it can also be used as a base resin for fiber-reinforced resins, and is particularly suitable as a prepreg with high heat resistance or a small dimensional change rate. Furthermore, the polymaleimide compound (A) contained in the curable composition can be coated because it has excellent solubility in various solvents. The heat-resistant components and electronic components obtained in this way can be applied to various uses, such as industrial machinery parts, general machinery parts, automobile, railway, vehicle parts, aerospace and aviation related parts, electronic and electrical parts, building materials, container and packaging components, daily necessities, sports and leisure products, wind power generation shell components, etc., but are not limited to these.

Hereinafter, representative products (circuit boards, semiconductor packaging materials, semiconductor devices, prepregs, build-up substrates, build-up films, and conductive pastes) manufactured using the curable resin composition of the present invention will be described with examples.

[Circuit board] This disclosure is a circuit board of a laminate of the following prepreg and copper foil. As a method of obtaining a printed circuit board from the curable composition of this embodiment, there can be cited a method of laminating the above-mentioned prepreg by a common method, appropriately stacking copper foil, and heating and pressing at 170 to 300°C for 10 minutes to 3 hours under a pressure of 1 to 10 MPa.

[Semiconductor packaging material] This disclosure is a semiconductor packaging material containing a curable composition of the present embodiment. The semiconductor packaging material obtained using the curable composition of the present embodiment has improved hygroscopicity and low dielectric loss tangent by using the polymaleimide compound (A) and amine compound (B) disclosed herein, so that the processability, formability, and reflow resistance in the manufacturing step are excellent, making it a better state. The curable composition of the present embodiment used in the aforementioned semiconductor packaging material may contain an inorganic filler. In addition, as the filling rate of the aforementioned inorganic filler, the inorganic filler can be used in a range of 0.5 to 1200 parts by mass relative to 100 parts by mass of the curable composition of the present embodiment. In addition, as mentioned above, the inorganic filler material may include, for example, barium sulfate, barium titanate, amorphous silica, crystalline silica, Neuburg siliceous earth, fused silica, spherical silica, talc, clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, silicon nitride, aluminum nitride, etc.

As a method for obtaining the aforementioned semiconductor packaging material, there can be cited the following method: In the curable composition of the present embodiment, a curing accelerator and/or additive of any component is melt-mixed sufficiently as needed until it becomes uniform using an extruder, a kneader, a roll, etc. When used as a high heat conductivity semiconductor packaging material for power transistors and power ICs, a high filling of crystalline silica, alumina, silicon nitride, etc. having a higher thermal conductivity than molten silica, or molten silica, crystalline silica, alumina, silicon nitride, etc. can be used. The filling rate is preferably 30 to 95 parts by mass of the inorganic filler per 100 parts by mass of the curable composition. In order to improve flame retardancy, moisture resistance, and solder crack resistance and reduce the linear expansion coefficient, it is more preferably 70 parts by mass or more, and further preferably 80 parts by mass or more.

[Semiconductor device] The present disclosure is a semiconductor device comprising a cured product of the aforementioned semiconductor packaging material. The semiconductor device obtained by using the semiconductor packaging material obtained by using the curable composition of the present embodiment has low viscosity and excellent fluidity due to the use of the polymaleimide compound (A) and amine compound (B) disclosed herein. In addition, due to the improvement of moisture absorption, thermoelastic modulus or adhesion with metal materials, the processability, formability and reflow resistance in the manufacturing step are excellent, thus becoming a better state.

As a method for obtaining the aforementioned semiconductor device, there can be cited a method of molding the aforementioned semiconductor packaging material using a casting molding machine, a transfer molding machine, an injection molding machine, etc., and further heating and curing it at a temperature range of room temperature (20°C) to 250°C.

[Prepreg] The present invention discloses a semi-cured prepreg having a reinforcing substrate and a curable composition of the present embodiment impregnated in the reinforcing substrate. As a method for obtaining a prepreg from the curable composition, there can be listed: mixing with an organic solvent described later, impregnating the varnished curable composition into a reinforcing substrate (paper, glass cloth, glass non-woven fabric, aramid paper, aramid cloth, glass felt, glass fiber yarn cloth, etc.), and then heating at a heating temperature corresponding to the type of solvent used, preferably 50 to 170°C, so that the curable composition is semi-cured (or uncured) to obtain a prepreg. The mass ratio of the curable composition and the reinforcing substrate used at this time is not particularly limited, but it is generally preferred to adjust the resin content in the prepreg to 20-60 mass %. In this embodiment, the semi-cured material of the curable composition is obtained by adjusting the heating temperature and heating time, and stopping the curing reaction in the middle without completing it. In addition, for example, the semi-cured material can have a curing degree of, for example, 85% or less and 5% or more. On the other hand, the cured material in this embodiment can have a higher curing degree than the semi-cured material. In addition, the curing degree of the semi-cured material can be calculated by the following formula by measuring the curing heat generated when the curable composition is heated and the curing heat generated by the semi-cured material by DSC. Curing degree (%) = [1-(curing heat generated by the semi-cured material/curing heat generated by the curing composition)] × 100

As the organic solvent used in the production of the prepreg of the present embodiment, for example, there can be listed methyl ethyl ketone, acetone, dimethylformamide, methyl isobutyl ketone, methoxypropanol, cyclohexanone, methyl thiocyanate, ethyl diglycol acetate, propylene glycol monomethyl ether acetate, etc., and their selection and appropriate amount of use can be appropriately selected according to the application. However, for example, as described below, in the case of further producing a printed circuit board from the prepreg, it is preferred to use a polar solvent having a boiling point of 160° C. or less, such as methyl ethyl ketone, acetone, and dimethylformamide, and it is preferred that the non-volatile component is used in a ratio of 40 to 80 mass %. Furthermore, the reinforcing substrate used in the manufacture of the prepreg of the present embodiment includes inorganic fibers such as glass fibers, polyester fibers, and polyamide fibers, woven or nonwoven fabrics including organic fibers, or pads, papers, etc., and these can be used alone or in combination.

The heat treatment conditions of the prepreg of this embodiment are appropriately selected according to the type and amount of the organic solvent, catalyst, and various additives used, but are generally preferably carried out at a temperature of 80 to 220° C. for 3 to 30 minutes.

[Build-up substrate] As a method for obtaining a build-up substrate from the curable composition of the present embodiment, a method through the following steps 1 to 3 can be listed. In step 1, first, the aforementioned curable composition appropriately mixed with rubber, filler, etc. is applied to the circuit substrate on which the circuit is formed by using a spray coating method, a curtain coating method, etc., and then cured. In step 2, as needed, after opening a designated through hole portion, etc. on the circuit substrate on which the curable composition is applied, it is treated with a roughening agent, and its surface is washed with hot water to form bumps on the aforementioned substrate, and a metal such as copper is plated. In step 3, the operations of steps 1 to 2 are repeated in sequence as needed, and the resin insulation layer and the conductor layer of the specified circuit pattern are alternately stacked (built up) to form a build-up substrate. In addition, in the aforementioned steps, the opening of the through hole portion can be performed after the outermost resin insulation layer is formed. In addition, the build-up substrate in this embodiment can also be made by heating and pressing the copper foil with resin formed by semi-hardening the composition on the copper foil at 170 to 300°C on the wiring substrate with the circuit formed, thereby omitting the steps of forming a roughened surface and plating treatment to produce a build-up substrate.

[Build-up film] This disclosure is a build-up film containing the curable composition of the present embodiment. As a method for manufacturing the build-up film of the present embodiment, it can be listed as: after applying the above-mentioned curable composition on a support film (Y), it is dried to form a layer of the curable composition on the support film (Y), and the method is used to manufacture it as a bonding film for a multi-layer printed wiring board. When a build-up film is made from a curable composition, it is important that the film softens under the temperature conditions of vacuum lamination (usually 70 to 140°C) and exhibits fluidity (resin flow) that allows resin filling in through holes or through-holes in the circuit substrate while laminating the circuit substrate. It is preferred to blend the above components in a manner that exhibits such characteristics. In addition, in the resulting build-up film and circuit substrate (copper-clad laminate, etc.), in order to avoid the phenomenon of locally different characteristic values due to phase separation, etc., and to exhibit certain performance in any part, appearance uniformity is required.

Here, the diameter of the through hole of the multi-layer printed wiring board is usually 0.1-0.5mm, and the depth is usually 0.1-1.2mm. It is usually better to fill the resin within this range. In addition, when the two sides of the circuit substrate are laminated, it is better to fill about 1/2 of the through hole.

Specifically, the method for manufacturing the above-mentioned adhesive film can be, after preparing the above-mentioned curable resin composition in a varnish state, applying the varnish-like composition on the surface of the supporting film (Y), and further drying the organic solvent by heating or blowing hot air, etc., to form a composition layer (X) composed of the curable composition, thereby manufacturing. As the organic solvent, for example, ketones such as acetone, methyl ethyl ketone, and cyclohexanone, acetates such as ethyl acetate, butyl acetate, thiourea acetate, propylene glycol monomethyl ether acetate, and carbitol acetate, carbitols such as thiourea and butyl carbitol, aromatic hydrocarbons such as toluene and xylene, dimethylformamide, dimethylacetamide, and N-methylpyrrolidone are preferably used. Furthermore, it is preferred that the non-volatile component be used in a ratio of 30 to 60% by mass.

The thickness of the formed composition layer (X) is usually preferably set to be greater than the thickness of the conductor layer. Since the thickness of the conductor layer of the circuit substrate is usually in the range of 5 to 70 μm, the thickness of the resin composition layer is preferably 10 to 100 μm. Furthermore, the composition layer (X) in this embodiment can also be protected by a protective film described later. By protecting with a protective film, dust and the like can be prevented from adhering to and damaging the surface of the resin composition layer.

The above-mentioned support film (Y) and protective film can be listed as follows: polyolefins such as polyethylene, polypropylene, polyvinyl chloride, etc., polyesters such as polyethylene terephthalate (hereinafter also referred to as "PET"), polyethylene naphthalate, etc., polycarbonate, polyimide, and even metal foils such as release paper, copper foil, and aluminum foil. In addition, the support film and the protective film can be subjected to release treatment in addition to matte treatment and corona treatment. Although the thickness of the support film is not particularly limited, it is usually used in the range of 10 to 150 μm, preferably in the range of 25 to 50 μm. In addition, the thickness of the protective film is preferably set to 1 to 40 μm.

The supporting film (Y) is peeled off after being laminated on the circuit substrate or after forming an insulating layer by heat curing. If the supporting film (Y) is peeled off after the subsequent film is heat cured, the adhesion of dust, etc., during the curing step can be prevented. In the case of peeling off after curing, the supporting film is usually subjected to a demolding treatment in advance. In addition, a multi-layer printed circuit substrate can be manufactured from the layered film obtained as described above. For example, when the resin composition layer (X) is protected by a protective film, after peeling off the protective film, the resin composition layer (X) is laminated on one or both sides of the circuit substrate by vacuum lamination, so as to be in direct contact with the circuit substrate. The lamination method can be batch-type or roll-to-roll continuous. In addition, the build-up film and the circuit substrate can be heated (preheated) as needed before lamination. The lamination conditions are preferably a lamination temperature of 70 to 140°C, a lamination pressure of 1 to 11 kgf/cm ² (9.8×10 ⁴ to 107.9×10 ⁴ N/m ² ), and lamination is preferably performed under reduced pressure of 20 mmHg (26.7 hPa) or less.

<Conductive paste> As a method for obtaining a conductive paste from the curable composition of the present invention, for example, there can be cited a method of dispersing conductive particles in the composition. The conductive paste can be used as a paste resin composition for circuit connection or an anisotropic conductive adhesive depending on the type of conductive particles used. [Example]

The present invention is described in more detail by way of examples and comparative examples, but the following "parts" and "%" are based on mass unless otherwise specified. In addition, the physical properties of the synthesized polymaleimide compound (A) were measured as follows and are shown in Table 1.

(1) Amine equivalent The amine equivalent of the intermediate amine compound (c) was measured by the following measurement method. In a 500 mL Erlenmeyer flask with a stopper, approximately 2.5 g of the intermediate amine compound (c) as a sample, 7.5 g of pyridine, 2.5 g of acetic anhydride, and 7.5 g of triphenylphosphine were accurately weighed, and a cooling tube was installed. The mixture was heated to reflux in an oil bath set at 120°C for 150 minutes. After cooling, 5.0 mL of distilled water, 100 mL of propylene glycol monomethyl ether, and 75 mL of tetrahydrofuran were added, and titrated with 0.5 mol/L potassium hydroxide-ethanol solution by potentiometric titration. A blank test was performed in the same manner for correction. Amine equivalent (g/equivalent) = (S×2,000)/(Blank-A) S: Sample amount (g) A: Consumption of 0.5mol/L potassium hydroxide-ethanol solution (mL) Blank: Consumption of 0.5mol/L potassium hydroxide-ethanol solution in blank test (mL)

(2) GPC measurement Using the following measuring device and measuring conditions, the number average molecular weight (Mn), weight average molecular weight (Mw) and molecular weight distribution (Mw/Mn) of the polymaleimide compound (A) obtained in the examples and comparative examples were calculated. "Measurement device" "HLC-8320 GPC" manufactured by Tosoh Co., Ltd. "Measurement conditions" Column: Guard column "HXL-L" manufactured by Tosoh Co., Ltd. + "TSK-GEL G2000HXL" manufactured by Tosoh Co., Ltd. + "TSK-GEL G2000HXL" manufactured by Tosoh Co., Ltd. + "TSK-GEL G3000HXL" manufactured by Tosoh Co., Ltd. + "TSK-GEL G4000HXL" manufactured by Tosoh Co., Ltd. Detector: RI (differential refractometer) Data processing: "GPC Workstation EcoSEC-WorkStation" manufactured by Tosoh Co., Ltd. Measurement conditions: Column temperature 40℃ Development solvent Tetrahydrofuran Flow rate 1.0ml/min Standard: According to the measurement manual of the aforementioned "GPC Workstation EcoSEC-WorkStation", the following monodisperse polystyrene with known molecular weight was used. (Polystyrene is used) Tosoh Co., Ltd. "A-500" Tosoh Co., Ltd. "A-1000" Tosoh Co., Ltd. "A-2500" Tosoh Co., Ltd. "A-5000" Tosoh Co., Ltd. "F-1" Tosoh Co., Ltd. "F-2" Tosoh Co., Ltd. "F-4" Tosoh Co., Ltd. "F-10" Tosoh Co., Ltd. "F-20" Tosoh Co., Ltd. "F-40" Tosoh Co., Ltd. "F-80" Tosoh Co., Ltd. "F-128" Sample: A tetrahydrofuran solution of the polymaleimide compound (A) obtained in the synthesis example, in which the resin solid content is converted to 1.0 mass%, is filtered with a microfilter (50 μl).

(3) FD-MS measurement The FD-MS spectrum of the polymaleimide compound (A) obtained in the embodiment was measured using the following measuring device and measuring conditions. Measuring device: JMS-T100GC AccuTOF Measuring conditions Measuring range: m/z = 4.00 to 2000.00 Rate of change: 51.2 mA/min Final current value: 45 mA Cathode voltage: -10 kV Recording interval: 0.07 sec

(4) ¹³ C-NMR measurement The ¹³ C-NMR spectrum of the polymaleimide compound (A) obtained in the example was measured using the following measuring device and measuring conditions. ¹³ C-NMR: "JNM-ECZ400S" manufactured by JEOL RESONANCE Resonance frequency: 100 MHz Accumulated times: 4000 times Solvent: Chloroform-d Sample concentration: 12 mass % Relaxation reagent: Chromium (III) acetylacetonate

(5) Synthesis of polymaleimide compound (A) <Synthesis Example 1> Synthesis of polymaleimide compound (A-1) (I) Synthesis of intermediate amine compound (c-1) In a flask equipped with a thermometer, a cooling tube, a Dean-Stark trap and a stirrer, 242.4 g (2.0 mol) of 2-ethylaniline, 242 g of xylene and 80 g of activated clay were added, and the temperature was raised to 130°C while 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 NIPPON STEEL Chemical & Material) was added dropwise over 2 hours, and the mixture was directly reacted for 1 hour. Then, the temperature was raised to 190°C over 6 hours and maintained for 10 hours. After the reaction, the air is cooled to 100°C, diluted with 300 g of toluene, and the activated clay is removed by filtration. The solvent and low molecular weight substances such as unreacted products are distilled off under reduced pressure to obtain the intermediate amine compound (c-1). The amine equivalent of the intermediate amine compound (c-1) is 214 g/equivalent. (II) Maleimidation In a 2L flask equipped with a thermometer, a cooling tube, a Dean-Stark trap and a stirrer, 117.7 g (1.2 mol) of maleic anhydride and 700 g of toluene are added and stirred at room temperature. Then, a mixed solution of 214 g (1 equivalent) of the intermediate amine compound (c-1) and 175 g of DMF is dropped over 1 hour, and then allowed to react for 2 hours. 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 toluene was returned to the system and the dehydration reaction was carried out for 5 hours. After air cooling to room temperature, the mixture was neutralized with 49% NaOH. Then, toluene and water were distilled off under reduced pressure at 60°C, and 600 g of MEK (methyl ethyl ketone) was added to the DMF solution remaining in the flask. After the solution was heated to 60°C, the solution was separated three times with 200 g of ion exchange water to remove the salt in the solution. Furthermore, sodium sulfate was added for drying, and the mixture was concentrated under reduced pressure. The obtained reaction product was vacuum dried at 80°C to obtain a polymaleimide compound (A-1). The chemical structure and characteristic analysis of the polymaleimide compound (A-1) were confirmed by GPC, FD-MS and ¹³ C-NMR. The measurement results are shown in Figures 1A to 1C. According to the GPC measurement results, the Mn of the polymaleimide compound (A-1) was 998, the Mw was 367,834, and the Mw/Mn was 368.697.

<Examples 1 to 2 and Comparative Examples 1 to 3> <<Preparation of curable composition and preparation of cured product>> The polymaleimide compound (A-1) obtained in the above-mentioned synthesis example 1, the comparison maleimide (1) ("BMI-2300" manufactured by Yamato Chemical Industries, Ltd.), the comparison maleimide (2) ("BMI-5100" manufactured by Yamato Chemical Industries, Ltd.), the amine compound (B-1) (4,4'-diaminodiphenylmethane (manufactured by Tokyo Chemical Industry Co., Ltd.)) as the amine compound (B), the amine compound (B-2) (4,4'-methylenebis(2-ethyl-6-methylaniline)), and the DCPO ("PERCUMYL D (パークミル D)", Dicumyl　Peroxide manufactured by NOF Corporation) was mixed to prepare the curable compositions of Examples 1 to 2 and Comparative Examples 1 to 3.

Next, the curable compositions of Examples 1 to 2 and Comparative Examples 1 to 3 were cured using the following curing conditions to prepare cured products corresponding to the curable compositions of Examples 1 to 2 and Comparative Examples 1 to 3. Furthermore, the physical properties of dielectric constant, dielectric loss factor, and hygroscopicity were evaluated by the following method. The results are shown in Table 1. ＜＜Curing Conditions＞＞ Using a vacuum press, after 2 hours at 200°C, heat curing was performed at 250°C for 2 hours. Thickness after molding: 1.3mm ＜＜Evaluation of dielectric constant and dielectric loss factor＞＞ According to JIS-C-6481, the network analyzer "E8362C" manufactured by Agilent Technologies Co., Ltd. was used to measure the dielectric constant (Dk) and dielectric loss factor (Df) of the test piece at 10GHz after being absolutely dried and stored indoors at 23°C and 50% humidity for 24 hours by the cavity resonance method. ＜＜Evaluation of hygroscopicity＞＞ In this embodiment and comparative example, the evaluation method of low hygroscopicity is to calculate the hygroscopicity rate (%) by the following method for evaluation. A test piece of 5mm×55mm×1.3mm was cut from the hardened product obtained above, and after being kept at 85℃, 85%RH, and 1 atmosphere for 50 hours using a pressure cooker tester, the moisture absorption rate (%) was calculated using the following formula for evaluation. Moisture absorption rate (%) = (mass of the test piece after the test - mass of the test piece before the test) / (mass of the test piece before the test) × 100

[Table 1] Table 1 Embodiment 1 Embodiment 2 Comparison Example 1 Comparison Example 2 Comparison Example 3 Polymaleimide compound (A-1) (parts by weight) 20 20 Comparative Polymaleimide (1) (parts by weight) 20 Comparative Polymaleimide (2) (parts by weight) 20 20 Amine compound (B-1) (parts by mass) 3 3 3 Amine compound (B-2) (parts by mass) 3 3 Catalyst (DCPO) (weight) 0.23 0.23 0.23 0.23 0.23 characteristic Dielectric constant Dk(10GHz) 2.52 2.53 Cannot rate due to cracked resin board 2.67 2.69 Dielectric dissipation factor Df(10GHz) 0.0033 0.0026 0.0039 0.0035 Moisture absorption rate (%) 1.22 0.91 2.22 1.99

From the results shown in Table 1 above, when comparing Examples 1 to 2 with Comparative Examples 1 to 3, it can be confirmed that by using the curable composition containing polymaleimide compound (A) and amine compound (B) of Examples 1 to 2, low dielectric constant and low dielectric loss factor, and low moisture absorption rate under high temperature and high humidity are achieved. In addition, it is confirmed that by using the curable composition containing polymaleimide compound (A) and amine compound (B) of Examples 1 to 2, low moisture absorption, low dielectric constant and low dielectric loss factor during curing can be highly combined even in the frequency band above Sub6. [Possibility of industrial use]

According to the present disclosure, a curable composition and a cured product thereof can be provided which exhibit low dielectric properties and low moisture absorption rate during curing.

without

FIG1A shows the GPC measurement result of the polymaleimide compound (A-1) of Synthesis Example 1. FIG1B shows the FD-MS measurement result of the polymaleimide compound (A-1) of Synthesis Example 1. FIG1C shows the ¹³ C-NMR measurement result of the polymaleimide compound (A-1) of Synthesis Example 1.

without.

Claims (8)

A curable composition is characterized by comprising: a polymaleimide compound (A) containing a monocyclic or condensed polycyclic aromatic group having two or more linear or branched alkylene groups bonded thereto; and an amine compound (B). In the curable composition of claim 1, the polymaleimide compound (A) has a structural unit represented by the following general formula (1): (In the above general formula (1), ^R1 is independently an alkyl group, ^R2 is independently an alkyl group, an alkoxy group or an alkylthio group having 1 to 10 carbon atoms; an aryl group, an aryloxy group or an arylthio group having 6 to 10 carbon atoms; a cycloalkyl group having 3 to 10 carbon atoms; a halogen atom; a hydroxyl group; or an alkyl group; ^R3 , ^R4 , ^R5 and ^R6 are independently a hydrogen atom or a methyl group, and one of ^R3 and ^R4 is a hydrogen atom and the other is a methyl group, and one of ^R5 and ^R6 is a hydrogen atom and the other is a methyl group; ^X1 is a substituent represented by the following general formula (x); (In the general formula (x), ^R7 and ^R8 each independently represent a hydrogen atom or a methyl group, and one of ^R7 and ^R8 is a hydrogen atom and the other is a methyl group, and ^R9 each independently represents an alkyl group, an alkoxy group or an alkylthio group having 1 to 10 carbon atoms; an aryl group, an aryloxy group or an 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 hydroxyl group; t represents an integer from 0 to 4;) r is the average value of the number of substitutions of ^X1 per benzene ring bonded to ^X1 , and represents a number from 0 to 4, 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). A hardened product of the hardenable composition according to claim 1 or 2. A prepreg having a reinforcing base material and a semi-cured material of the curable composition of claim 1 or 2 impregnated in the reinforcing base material. A circuit substrate comprises a laminate of the prepreg as claimed in claim 4 and copper foil. A build-up film comprising the curable composition of claim 1 or 2. A semiconductor packaging material comprising the hardening composition of claim 1 or 2. A semiconductor device comprising a hardened semiconductor packaging material as claimed in claim 7.