CN116891632A

CN116891632A - Curable composition, cured product, prepreg, circuit board, laminate film, semiconductor sealing material, and semiconductor device

Info

Publication number: CN116891632A
Application number: CN202310255963.5A
Authority: CN
Inventors: 桥本慎太郎; 青山和贤; 下野智弘
Original assignee: DIC Corp
Current assignee: DIC Corp
Priority date: 2022-03-31
Filing date: 2023-03-16
Publication date: 2023-10-17
Also published as: TW202402945A; JP2023152757A; KR20230141566A

Abstract

Disclosed are a curable composition, a cured product, a prepreg, a circuit board, a laminate film, a semiconductor sealing material, and a semiconductor device, each of which exhibits a low dielectric loss tangent and a low moisture absorption rate when cured. The present disclosure relates to a curable composition comprising a first maleimide compound (A1) and a second maleimide compound (A2) having a structural unit different from that of the first maleimide compound (A1), wherein the second maleimide compound (A2) is a compound having a maleimide group and a monocyclic or condensed polycyclic aromatic group to which 2 or more linear or branched alkylene groups are bonded.

Description

Curable composition, cured product, prepreg, circuit board, laminate film, semiconductor sealing material, and semiconductor device

Technical Field

The present disclosure relates to a curable composition, a cured product, a prepreg, a circuit board, a laminate film, a semiconductor sealing material, and a semiconductor device.

Background

A prepreg obtained by impregnating glass cloth with a thermosetting resin such as an epoxy resin or a BT (bismaleimide-triazine) resin, and heat-drying the same, a laminate obtained by heat-curing the prepreg, and a multilayer board obtained by combining the laminate and the prepreg and heat-curing the same are widely used as a circuit board material for electronic devices. Among these, the packaging substrate, which is one of the printed wiring boards that functions as an interposer for mounting semiconductors, is increasingly thinned, and warpage of the packaging substrate at the time of mounting is a problem, so that a material exhibiting high heat resistance is required in order to suppress warpage of the packaging substrate at the time of mounting.

In addition, in recent years, the signal has been accelerated and the frequency has been increased, and it has been desired to provide a thermosetting composition capable of forming a cured product which maintains a sufficiently low dielectric constant in these environments and exhibits a sufficiently low dielectric loss tangent. In particular, in various electric material applications, particularly advanced material applications, further improvements in properties such as heat resistance and dielectric characteristics and materials and compositions having these properties have been demanded recently. For these demands, maleimide resins are attracting attention as materials having both heat resistance and low dielectric constant and low dielectric loss tangent. However, conventional maleimide resins exhibit high heat resistance, but have high hygroscopicity, and dielectric properties (dielectric constant, dielectric loss tangent) do not reach the level required for advanced 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 board having a dielectric constant of 4.0 or less as a laminate without impairing heat resistance.

Prior art literature

Patent literature

Patent document 1: japanese patent laid-open No. 5-247202

Disclosure of Invention

Problems to be solved by the invention

However, the thermosetting resin composition of patent document 1 does not discuss the dielectric loss tangent, and therefore the dielectric loss tangent does not reach the level required for advanced material use, and further, does not satisfy both high glass transition temperature and low dielectric loss tangent. Further, since the transmission loss increases with higher frequencies, it is required to reduce the transmission loss in the high frequency region for the circuit board material. However, the technology of patent document 1 only discusses dielectric characteristics in a frequency band (in the range of hundreds MHz to 3 GHz) that has been used at present, and does not discuss whether or not it is possible to cope with a technology for a 5 th generation mobile communication system (5G) that uses a frequency band of so-called Sub6 or higher (for example, 3.6GHz or higher).

Accordingly, the technical problem to be solved by the present disclosure is to provide a curable composition, a cured product, a prepreg, a circuit board, a laminate film, a semiconductor sealing material, and a semiconductor device, which are hardly broken at the time of curing and exhibit a low dielectric loss tangent and a high glass transition temperature.

Means for solving the problems

As a result of intensive studies to solve the above problems, the present inventors have found that by using a curable composition containing a first maleimide compound (A1) and a second maleimide compound (A2) having a structural unit different from that of the first maleimide compound (A1), breakage at the time of curing is reduced, and a low dielectric loss tangent and a high glass transition temperature are exhibited, and the present invention has been completed by the fact that the second maleimide compound (A2) is a compound having a monocyclic or condensed polycyclic aromatic group and a maleimide group, to which 2 or more linear or branched alkylene groups are bonded.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present disclosure, a curable composition, a cured product, a prepreg, a circuit board, a laminate film, a semiconductor sealing material, and a semiconductor device, which are hardly broken upon curing and exhibit a low dielectric loss tangent and a high glass transition temperature, can be provided.

According to the present disclosure, it is possible to provide a curable composition, cured product, prepreg, circuit board, laminated film, semiconductor sealing material, and semiconductor device which are hard to crack even when cured at a frequency band of Sub6 or more and exhibit low dielectric loss tangent and high glass transition temperature. Such a curable composition is particularly useful for electronic component sealing material applications and the like.

Drawings

FIG. 1A shows GPC measurement results of polymaleimide compound (X) in Synthesis example 1.

FIG. 1B shows the FD-MS measurement result of the polymaleimide compound (X) in Synthesis example 1.

FIG. 1C shows the NMR measurement result of the polymaleimide compound (X) in Synthesis example 1.

Detailed Description

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

[ term ]

The "reaction raw material" in the present specification means a compound that partially constitutes the chemical structure of a target compound by a chemical reaction such as chemical combination or decomposition, and does not include a solvent, a catalyst, or the like that plays a role as an auxiliary agent for the chemical reaction. In the present specification, the "reaction raw material" particularly means, for example, a precursor for obtaining the second maleimide compound (A2) or a precursor compound thereof (for example, an intermediate amine compound (c) obtained by connecting the aromatic amine compounds (a) to each other via the aromatic divinyl compound (b 1)) by a chemical reaction when the second maleimide compound (A2) is used as a target.

The "aromatic group" in the present specification preferably has an aromatic ring having 3 to 30 carbon atoms, and more preferably has an aromatic ring having 4 to 26 carbon atoms. In the present specification, the "aromatic group" may be substituted with a substituent (for example, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a halogen atom) for a hydrogen atom of an aromatic ring in the aromatic group. In addition, the "aromatic group" includes a heteroaromatic group, and-CH in the "aromatic group ₂ -or-ch=may be substituted by-O-, -S-, or-n=in a manner not adjacent to each other.

Examples of the type of the aromatic ring include monocyclic aromatic rings and condensed polycyclic aromatic rings.

Examples of the monocyclic aromatic ring include benzene, furan, pyrrole, thiophene, imidazole, pyrazole, oxazole, isoxazole, thiazole, isothiazole, pyridine, pyrimidine, pyridazine, pyrazine, and triazine. Examples of the condensed polycyclic aromatic ring include naphthalene, anthracene, phenalene, phenanthrene, quinoline, isoquinoline, quinazoline, phthalazine, naphthyridine, coumarin, indole, benzimidazole, benzofuran, and acridine. The hydrogen atom of the aromatic ring in the aromatic group may be substituted with, 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.

The monovalent aromatic group means a group obtained by removing 1 hydrogen atom from the "aromatic group", the divalent aromatic group means a group obtained by removing 2 hydrogen atoms from any one of the "aromatic group", and the trivalent to hexavalent aromatic group means a group obtained by removing 3 to 6 hydrogen atoms from the "aromatic group".

Examples of the "cyclic hydrocarbon group" in the present specification include biphenylene, terphenylene, and a group having 1 or more benzene rings and 1 or more indane rings. Examples of the group having 1 or more benzene rings and 1 or more indane rings include groups represented by the following general formula (M).

(in the formula (M), R ^b Independently represent an alkyl group having 1 to 10 carbon atoms, an alkoxy group or an alkylthio group, an aryl group having 6 to 10 carbon atoms, an aryloxy group or an arylthio group, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a hydroxyl group or a mercapto group, q ^A1 And q ^A2 Each independently represents an integer value of 0 to 3. q ^A1 And q ^A2 In the case of 2 to 3, R ^b May be the same or different within the same ring. n is n ^A1 The average number of repeating units is a number of 0.95 to 10.0. )

Examples of the "aralkyl group" in the present specification include benzyl, diphenylmethyl, naphthylmethyl and the like. The hydrogen atom of the aromatic ring in the aralkyl group may be substituted with, 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. The "aralkylene group" may be a divalent group obtained by removing 1 hydrogen atom from the above-mentioned "aralkyl group".

The "alkyl" in the present specification may be any of straight-chain, branched or cyclic, and examples thereof include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, 1, 2-dimethylpropyl, n-hexyl, isohexyl, (n) heptyl, (n) octyl, (n) nonyl, (n) decyl, (n) undecyl, (n) dodecyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl or cyclononyl.

The "cycloalkyl" in the present specification may be exemplified by cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, methylcyclobutyl, norbornenyl, adamantyl, and the like.

As the "alkylthio group" in the present specification, there may be mentioned a methylthio group, an ethylthio group, a propylthio group, a butylthio group, an octylthio group or a 2-ethylhexyl thio group.

As the "alkenyl" in the present specification, there may be mentioned ethynyl, 1-propynyl, 2-butynyl, pentynyl, hexynyl, vinyl, allyl, isopropenyl and the like.

Examples of the "alkoxy" in the present specification include methoxy, ethoxy, propoxy, isopropoxy, butoxy, pentyloxy, hexyloxy, 2-ethylhexyl oxy, octyloxy, nonyloxy and the like.

Examples of the "aryl" in the present specification include phenyl, naphthyl, phenalkenyl, phenanthryl, anthracyl, azulenyl (azulenyl), and tetralin. In the "aryl group", the hydrogen atom of the aromatic ring in the aryl group may be substituted with, 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. The "arylene group" may be a divalent group obtained by removing 1 hydrogen atom from the above-mentioned "aryl group".

Examples of the "aryloxy group" in the present specification include phenoxy group, naphthyloxy group, anthracenyloxy group, phenanthrenyloxy group, pyrenyloxy group and the like.

As the "arylthio group" in the present specification, arylthio groups such as phenylthio, naphthylthio, anthrylthio, phenanthrylthio and pyrenylthio are mentioned.

Examples of the "halogen atom" in the present specification include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

The "structural unit" in the present specification means a (repeating) unit of a chemical structure formed at the time of reaction or polymerization, in other words, means a partial structure other than a structure of a chemical bond participating in the reaction or polymerization in a product compound formed by the reaction or polymerization, and means a so-called residue.

[ curable composition ]

The curable composition of the present embodiment is a curable composition containing 2 or more maleimide compounds, and the maleimide compound contains a maleimide compound (A2) having a maleimide group and a mono-or condensed polycyclic aromatic group to which 2 or more linear or branched alkylene groups are bonded.

In other words, the curable composition of the present embodiment is a curable composition containing a first maleimide compound (A1) and a second maleimide compound (A2) having a structural unit different from that contained in the first maleimide compound (A1) (hereinafter simply referred to as a second maleimide compound (A2)), and the second maleimide compound (A2) is a compound having a mono-or condensed polycyclic aromatic group having 2 or more linear or branched alkylene groups bonded thereto and a maleimide group.

Since the second maleimide compound (A2) having a small proportion of polar functional groups in the chemical structure is present, the composition as a whole can exhibit low dielectric characteristics and high glass transition temperature. In addition, since the cured product exhibits moderate toughness during curing, cracking of the cured product itself can be reduced. In addition, it is possible to provide a composition for use in a cured product which is hardly broken even in a frequency band of Sub6 or more and which exhibits a low dielectric loss tangent and a high glass transition temperature.

By exhibiting a high glass transition temperature, thermal deformation can be suppressed, prevented, and/or heat resistance can be improved.

In the curable composition of the present embodiment, the first maleimide compound (A1) and the second maleimide compound (A2) are preferably used in a ratio (parts by mass) of 90:10 to 10:90, more preferably 80:20 to 20:80, still more preferably 75:25 to 25:75, as the components of the first maleimide compound (A1) and the second maleimide compound (A2). By adjusting the blending ratio within the above range, it is possible to exhibit a high glass transition temperature and an excellent low dielectric loss tangent, and thus preferable.

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

Hereinafter, the first maleimide compound (A1) and the second maleimide compound (A2), which are essential components of the curable composition of the present embodiment, will be described in detail, and then the curing agent (B), the other resin (C), the curing accelerator, and the additive, which are optional components, will be described.

(first maleimide Compound (A1))

The first maleimide compound (A1) according to the present embodiment may be a compound having 2 or more maleimide groups, and may have a chemical structure different from that of the second maleimide compound (A2) described later.

The first maleimide compound (A1) is a compound in which 2 or more maleimide groups are linked via a linking group, and the linking group is preferably a linear or branched alkylene group having 14 to 30 carbon atoms or a linear or branched alkylene group having 1 to 12 carbon atoms, which is a cyclic hydrocarbon group. More specifically, the first maleimide compound (A1) is preferably a compound having a structural unit in which 2 or more maleimide groups represented by the following general formula (M1) are linked to a linking group represented by the following general formula (M2).

(in the above general formula (M1), ar ^M1 The term "aromatic group" means an aromatic group, and the dotted line is absent or represents a single bond, and the term "attached to another atom (for example, in the following general formula (M2)"). )

*-L ¹ -Ar ^M2 -L ² -* (M2)

(in the above general formula (M2), ar ^M2 Represents a single bond or a cyclic hydrocarbon group, L ¹ And L ² Each independently represents a single bond or a linear or branched alkylene group, however, L ¹ And L ² Any one of which is a linear or branched alkylene group, and which represents a group bonded to another atom (for example, in the above general formula (M1)Is) is connected. )

In the general formula (M1), the dotted line indicates that a single bond is not present or is represented. When the dotted line is absent, the maleimide group represented by the general formula (M1) may be 1-valent. On the other hand, when the broken line represents a single bond, the maleimide group represented by the general formula (M1) may be divalent.

As a preferred embodiment of the first maleimide compound (A1) represented by the above general formula (M1) and the general formula (M2), a compound having 2 or more maleimide groups represented by the above general formula (M1) linked by 1 or more linking groups represented by the general formula (M2) is preferable, and a compound having 2 or more to 5 or less maleimide groups represented by the above general formula (M1) linked by 1 or more linking groups represented by the general formula (M2) or less is more preferable.

The preferred first maleimide compound (A1) of the present embodiment is preferably a compound having 1 to 4 maleimide groups, more preferably 2 to 3 maleimide groups, and particularly preferably a bismaleimide compound. The blending of the bismaleimide compound in the curable composition is preferable from the viewpoint of heat resistance.

As a specific example of the first maleimide compound (A1) of the present embodiment, for example, 1 or 2 or more compounds selected from the group consisting of compounds represented by the following formulas (A1-1) and (A1-2) are particularly preferable. In view of importance attached to low dielectric loss tangent and water absorption, the first maleimide compound (A1) is more preferably a compound represented by the formula (A1-2).

(in the above general formula (A-1), R ^A1 And R is ^A2 Independently represent an alkyl group or an alkoxy group having 1 to 10 carbon atoms, L ³ Represents an alkylene group having 1 to 10 carbon atoms, n ^A1 And n ^A2 Each independently represents an integer of 1 to 4. )

(in the formula (A1-2), R ^a Independently represent an alkyl group having 1 to 10 carbon atoms, an alkoxy group or an alkylthio group, an aryl group having 6 to 10 carbon atoms, an aryloxy group or an arylthio group, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a nitro group, a hydroxyl group or a mercapto group, p ^A1 And p ^A2 An integer value of 0 to 4 is represented. P is p ^A1 And p ^A2 In the case of 2 to 4, R ^a May be the same or different within the same ring. R is R ^b Independently represent an alkyl group having 1 to 10 carbon atoms, an alkoxy group or an alkylthio group, an aryl group having 6 to 10 carbon atoms, an aryloxy group or an arylthio group, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a hydroxyl group or a mercapto group, q ^A1 And q ^A2 Each independently represents an integer value of 0 to 3. q ^A1 And q ^A2 In the case of 2 to 3, R ^b May be the same or different within the same ring. n is n ^A1 The average number of repeating units is a number of 0.95 to 10.0. )

The above q ^A1 And q ^A2 P as described above ^A1 And p ^A2 When 0, R is ^a And R is ^b Respectively, hydrogen atoms.

In this embodiment, a commercially available compound or a compound synthesized by the above formula (A1-1) may be used. For example, BMI series manufactured by Dai Kagaku Co., ltd, preferably 4,4' -diphenylmethane bismaleimide, phenylmethane maleimide, m-phenylene bismaleimide, bisphenol A diphenylether bismaleimide, 3' -dimethyl-5, 5 ' -diethyl-4, 4' -diphenylmethane bismaleimide, 4-methyl-1, 3-phenylene bismaleimide or 1,6' -bismaleimide- (2, 4-trimethyl) hexane and the like are examples of commercially available compounds.

Since the first maleimide compound (A1) has an indane skeleton, the proportion of polar functional groups in the structure is small, and thus a cured product produced using the maleimide compound represented by the general formula (A1-2) is preferable because of excellent dielectric characteristics. Further, since the cured product using the conventional maleimide resin tends to be brittle and is liable to be poor in brittleness resistance, the maleimide compound represented by the general formula (A1-2) has an indane skeleton, and therefore, it is preferable that the entire curable composition of the second maleimide compound (A2) containing the general formula (A1-2) and having a mono-or condensed polycyclic aromatic group having 2 or more linear or branched alkylene groups and a maleimide group attached thereto is excellent in flexibility and softness at the time of curing, and an improvement in brittleness resistance is expected.

In addition, R of the above general formula (A1-2) ^a The above alkyl group having 1 to 4 carbon atoms, cycloalkyl group having 3 to 6 carbon atoms, aryl group having 6 to 10 carbon atoms are preferable, and the use of the alkyl group having 1 to 4 carbon atoms is preferable because the planarity in the vicinity of the maleimide group is reduced, the crystallinity is reduced, the solvent solubility is improved, and the reactivity of the maleimide group is not impaired, thereby obtaining a cured product.

P in the above general formula (A1-2) ^A1 And p ^A2 Each independently is preferably 2 to 3, more preferably 2. Above p ^A1 And p ^A2 When each is independently 2, the effect of steric hindrance is small, and the electron density on the aromatic ring is increased, which is a preferable mode in the production (synthesis) of maleimide.

Q in the above general formula (A1-2) ^A1 And q ^A2 Is 0, R ^b Preferably a hydrogen atom, in addition, q ^A1 And q ^A2 Each independently is 1 to 3, R ^b Preferably at least 1 selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms and an aryl group having 6 to 10 carbon atoms, particularly by q ^A1 And q ^A2 Is 0, R ^b The hydrogen atom is advantageous for the production (synthesis) of maleimide because it reduces steric hindrance when forming an indane skeleton in maleimide.

The molecular weight distribution (weight average molecular weight (Mw)/number average molecular weight (Mn)) of the first maleimide compound (A1) represented by the above general formula (A1-2) as measured by Gel Permeation Chromatography (GPC) is preferably in the range of 1.0 to 4.0, more preferably 1.1 to 3.8, even more preferably 1.2 to 3.6, particularly preferably 1.3 to 3.4, from the viewpoint of excellent low dielectric constant and low dielectric loss tangent.

The Gel Permeation Chromatography (GPC) measurement method is the method described in the example column.

In the curable composition of the present embodiment, the content of the first maleimide compound (A1) is preferably 5 mass% or more and 95 mass% or less, and most preferably 30 mass% or more and 70 mass% or less, with respect to 100 mass% of the total curable composition. When the content of the first maleimide compound (A1) is in the range of 30 mass% to 70 mass%, it is preferable from the viewpoint of low dielectric loss tangent.

(second maleimide Compound (A2))

The second maleimide compound (A2) according to the present embodiment is a compound having a structural unit different from that contained in the first maleimide compound (A1) and having a mono-or condensed polycyclic aromatic group to which 2 or more linear or branched alkylene groups are bonded, and a maleimide group.

The single-ring or condensed polycyclic aromatic group having 2 or more linear or branched alkylene groups bonded thereto is a divalent or more group having 2 or more linear or branched alkylene groups having 1 to 12 carbon atoms and one bond of 2 or more alkylene groups bonded to a single-ring or condensed polycyclic aromatic ring. Thus, the number of straight-chain or branched alkylene groups bonded to the monocyclic or condensed polycyclic aromatic ring corresponds to the valence of the alkylene group containing the aromatic ring. In this embodiment, the monocyclic or condensed polycyclic aromatic group to which 2 or more linear or branched alkylene groups are bonded is preferably a group having a valence of 2 to 4, more preferably a group having a valence of 2 to 3.

In addition, in the molecule of the second maleimide compound (A2) of the present embodiment, a single-ring or condensed polycyclic aromatic group having 2 or more linear or branched alkylene groups bonded thereto is preferable as a structural unit different from that contained in the first maleimide compound (A1). Thus, the performance of both the low dielectric characteristics of (A2) and the high glass transition temperature of (A1) is exhibited, and the low dielectric characteristics and the high glass transition temperature can be exhibited as compared with the case of using them alone.

In the present embodiment, the monocyclic or condensed polycyclic aromatic group to which 2 or more linear or branched alkylene groups are bonded is preferably a group represented by the following general formula (I).

(in the above general formula (I), ar ¹ An aromatic group represented by the formula (2+h), L ¹ 、L ² And L ³ Each independently represents an alkylene group having 1 to 12 carbon atoms, h represents an integer of 0 to 2 inclusive, and each represents a bond to another atom. )

In the general formula (I), the group represented by the general formula (I) is 2-valent when h is 0, and the group represented by the general formula (I) is 4-valent when h is 2.

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

(in the above general formula (II), ar ² The aromatic group is represented, the dotted line is absent or represents a single bond, and the dotted line represents a connection to another atom. )

In the general formula (II), the dotted line indicates that a single bond is not present or represented. When the dotted line is absent, the maleimide group of the general formula (II) may be 1-valent. On the other hand, when the broken line represents a single bond, the maleimide group of the general formula (II) may be 2-valent.

The second maleimide compound (A2) of the present embodiment is preferably a compound having a structural unit represented by the following general formula (1), or a compound having an aromatic amine compound (a) (hereinafter, also referred to as an aromatic amine compound (a)), an aromatic divinyl compound (b 1) (hereinafter, also referred to as an aromatic divinyl compound (b 1)) having 2 vinyl groups, and maleic anhydride as the reaction raw materials (1).

(in the above general formula (1), R ¹ Each independently represents an alkyl group,

R ² independently represent an alkyl group having 1 to 10 carbon atoms, an alkoxy group or an alkylthio group; aryl, aryloxy or arylthio groups having 6 to 10 carbon atoms; cycloalkyl having 3 to 10 carbon atoms; a halogen atom; a hydroxyl group; or a mercapto group, or a thiol group,

R ³ 、R ⁴ 、R ⁵ and R is ⁶ Each independently represents a hydrogen atom or a methyl group, and R ³ And R is ⁴ One of them is hydrogen atom and the other is methyl, R ⁵ And R is ⁶ One of which is a hydrogen atom and the other is a methyl group,

X ¹ represents a substituent represented by the following general formula (x),

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

r is X is connected to each 1 ¹ X of benzene ring of (B) ¹ The average value of the substitution numbers of (a) 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. )

This makes it possible to achieve both low hygroscopicity and low dielectric loss tangent at a higher level during curing.

< preferred embodiment of the second maleimide Compound (A2) >

The second maleimide compound (A2) of the present embodiment preferably has a structural unit represented by the above general formula (1).

In the general formula (1), when p is an integer of 2 or more, a plurality of R's are present ¹ May be the same as or different from each other. q is an integer of 2 or more, and a plurality of R's are present ² May be the same as or different from each other. When t is an integer of 2 or more, a plurality of R's are present ⁹ May be the same as or different from each other.

In the general formula (1), R ¹ Each independently preferably represents an alkyl group having 1 to 10 carbon atoms, and more preferably represents an alkyl group having 1 to 6 carbon atoms. In addition, when p is an integer of 2 or more, a plurality of R's are present ¹ May be the same as or different from each other. R is preferably as in the formula (1) ¹ Methyl, ethyl or n-propyl. R in the general formula (1) ¹ The benzene ring to which it is attached may be the benzene ring of the aromatic amine compound (a).

In the above general formula (1), p preferably represents 1 or 2. R in the general formula (1) is preferable ¹ At least one of the 2-, 3-, 4-, 5-or 6-positions of the benzene ring attached is attached with R ¹ 。

In the general formula (1), R ² Each independently preferably 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 represents an alkyl group having 1 to 10 carbon atoms, and still more preferably represents an alkyl group having 1 to 6 carbon atoms. In addition, when q is an integer of 2 or more, a plurality of R's are present ² May be the same as or different from each other. R is preferably as in the formula (1) ² Methyl, ethyl or n-propyl. R in the general formula (1) ² The benzene ring attached may be an aromatic divinyl compound(b1) A benzene ring of (a) is used. In the general formula (1), q preferably represents 0, 1 or 2.

In the general formula (1), R ³ And R is ⁴ One of them is hydrogen atom and the other is methyl, R ⁵ And R is ⁶ One of which is a hydrogen atom and the other is a methyl group. This can maintain the reactivity of the unsaturated bond of the second maleimide compound (A2) itself at a high level. R in the above general formula (1) ³ 、R ⁴ 、R ⁵ And R is ⁶ If the proportion of the alkyl group is increased, the reactivity of the unsaturated bond possessed by the second maleimide compound (A2) itself may be expected to be lowered due to steric hindrance thereof. Thus, R is ³ 、R ⁴ 、R ⁵ And R is ⁶ If all of the groups are alkyl groups, the reactivity of the unsaturated bonds of the second maleimide compound (A2) itself is lowered, and a cured product cannot be efficiently formed.

In the general formula (1), X ¹ Represented by the above general formula (x), and in the general formula (x), R ⁷ Preferably represents a hydrogen atom, R ⁸ Preferably represents methyl. In the general formula (x), R is ⁹ Each independently preferably 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, and still more preferably an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 10 carbon atoms. In the general formula (x), t preferably represents an integer of 0 to 4, and more preferably represents an integer of 0 to 3. When t is an integer of 2 or more, a plurality of R's are present ⁹ May be the same as or different from each other.

In the above general formula (1), r means that X is bonded to each 1 ¹ X of benzene ring of (B) ¹ The average value of the number of substitution is preferably in the range of 0 to 4, 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 still more preferably an integer of 1 to 80.

The preferred second maleimide compound (A2) of the present embodiment is preferably a polymaleimide compound. The maleimide groups in the second maleimide compound (A2) are preferably 2 to 20, more preferably 2 to 15, still more preferably 2 to 10, on average, per molecule. The combination of the first maleimide compound (A1) being a bismaleimide compound and the second maleimide compound (A2) being a polymaleimide compound having an average of 2 to 10 maleimide groups per molecule is preferable from the viewpoints of curability and heat resistance.

In the curable composition of the present embodiment, the content of the second maleimide compound (A2) is preferably 5 mass% or more and 95 mass% or less, and most preferably 20 mass% or more and 80 mass% or less, with respect to 100 mass% of the total curable composition. When the content of the second maleimide compound (A2) is in the range of 20 mass% to 80 mass%, it is preferable from the viewpoints of curability and low dielectric loss tangent.

< other preferred modes of the second maleimide Compound (A2) >

As another preferable embodiment of the second maleimide compound (A2) of the present embodiment, an aromatic amine compound (a) having 1 to 3 alkyl groups, an aromatic divinyl compound (b 1) having 2 vinyl groups, and maleic anhydride may be used as the reaction raw material (1). In this case, in the present embodiment, the reaction raw material (1) may further contain an aromatic monovinyl compound (b 2) having 1 vinyl group (hereinafter, also referred to as an aromatic monovinyl compound (b 2)). The second maleimide compound (A2) of the present embodiment is preferably an intermediate amine compound (c) obtained by crosslinking aromatic amine compounds (a) having 1 to 3 alkyl groups with aromatic divinyl compounds (b 1) having 2 vinyl groups, and a second maleimide compound (A2) obtained by crosslinking maleic anhydride as the reaction raw material (3). Further, the intermediate amine compound (c) is preferably a compound obtained by using, as the reaction raw material (2), an aromatic amine compound (a) having 1 to 3 alkyl groups, an aromatic divinyl compound (b 1) having 2 vinyl groups, and an aromatic monovinyl compound (b 2) having 1 vinyl group, if necessary.

In other words, the intermediate amine compound (c) in the present embodiment preferably has the following structure: an aromatic ring having an amino group (substituted amino group obtained by further substituting an alkyl group having 1 to 6 carbon atoms for a hydrogen atom of the amino group) and a structural unit of the aromatic amine compound (a) having 1 or more and 3 or less alkyl groups on the aromatic ring is chemically bonded to a structural unit of the aromatic divinyl compound (b 1) having 2 vinyl groups, and the structural unit of the aromatic monovinyl compound (b 2) as required is chemically bonded to the aromatic ring in the structural unit of the aromatic amine compound (a). The second maleimide compound (A2) in the present embodiment has an amino group (including-NH) attached to the aromatic ring of the intermediate amine compound (c) ₂ And substituted amino groups. ) Structure substituted with an N-substituted maleimide ring.

Thus, the "second maleimide compound (A2)" and the "intermediate amine compound (c)" as a precursor of the "second maleimide compound (A2)" in the present embodiment are obtained by reacting an amino group (including-NH) ₂ And substituted amino groups. ) Different polymer compounds in this regard are substituted with N-substituted maleimide rings.

The structural unit of the aromatic amine compound (a) is a group obtained by removing 2 hydrogen atoms from the aromatic ring of the aromatic amine compound (a). For example, in the case where the aromatic amine compound (a) is represented by the general formula (a) described below, a group obtained by removing 2 hydrogen atoms from the benzene ring of the general formula (a) is referred to as a structural unit of the aromatic amine compound (a). The structural unit of the aromatic divinyl compound (b 1) is a group obtained by cleavage of an unsaturated bond of 2 vinyl groups of the aromatic divinyl compound (b 1).

In the present embodiment, since the aromatic amine compound (a) having a specific aromatic ring structure is used as a reaction raw material, the reaction site with the aromatic divinyl compound (b 1) described later is easily controlled, and therefore the second maleimide compound (A2) having a uniform chemical structure or chain length is easily obtained, and as a result, the second maleimide compound (A2) exhibiting low hygroscopicity and low dielectric loss tangent at the time of curing can be provided.

Hereinafter, as constituent components of the reaction raw material (1) of the second maleimide compound (A2), the aromatic amine compound (a) having 1 to 3 alkyl groups, the aromatic divinyl compound (b 1) having 2 vinyl groups, the aromatic monovinyl compound (b 2) having 1 vinyl group as an optional component, and maleic anhydride will be described, and further preferred embodiments of the second maleimide compound (A2) and the method for producing the second maleimide compound (A2) will be described.

An aromatic amine Compound (a)

The aromatic amine compound (a) in the present embodiment has an amino group (-NH) attached thereto ₂ Or substituted amino group), and 1 to 3 alkyl groups are bonded to the aromatic ring. Accordingly, the aromatic amine compound (a) may be an amine compound. The aromatic ring forming the central structure of the aromatic amine compound (a) is preferably a monocyclic ring, and includes an aromatic hydrocarbon ring and an aromatic heterocyclic ring. The aromatic hydrocarbon ring is preferably a benzene ring. Examples of the aromatic heterocycle include a hetero six-membered ring such as a pyran ring and a pyridine ring. Further, the aromatic amine compound (a) in the present embodiment more preferably has-NH group to which an unsubstituted amino group is bonded ₂ And the aromatic ring is connected with 1 to 3 alkyl groups.

In the aromatic amine compound (a) of the present embodiment, the alkyl group substituted on 1 to 3 hydrogen atoms of the aromatic ring of the aromatic amine compound (a) may be an alkyl group having 1 to 10 carbon atoms, preferably an alkyl group having 1 to 6 carbon atoms, and more preferably an alkyl group having 1 to 3 carbon atoms. The alkyl group may be any of a linear type, a branched type, and a cyclic type. Examples thereof include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl and the like. The smaller the molecular weight of the above alkyl group, the more remarkable the effect (low dimensional change rate) achieved by the present invention. In addition, the higher the molecular weight of the alkyl group, the more remarkable the effect (low water absorption) achieved by the present invention.

Having amino groups (including-NH) from the aromatic ring ₂ And substituted amino groups. ) And 2 linkages can be used for polymerization, the aromatic amine compound (a) has an amino group (including-NH) ₂ And substituted amino groups. ) The upper limit of the number of alkyl groups bonded to the aromatic ring is a number obtained by subtracting 3 from the number of substitutable ring constituent atoms in the aromatic ring in the unsubstituted state. 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, the reaction site with the aromatic divinyl compound (b 1) described later can be easily controlled, and therefore the second maleimide compound (A2) having a uniform chemical structure or chain length can be easily obtained. As a result, the cured product of the second maleimide compound (A2) is likely to exhibit low hygroscopicity and excellent high-frequency electric characteristics.

A preferred embodiment of the aromatic amine compound (a) will be described with reference to the case where the aromatic ring of the aromatic amine compound (a) in the present embodiment is a benzene ring as an example.

In this embodiment, it is preferable that 1 or more carbon atoms having the largest HOMO electron density (shock modulus) among carbon atoms in the benzene ring constituting the aromatic amine compound (a) are unsubstituted (or substituted with hydrogen atoms).

Thereby, arS due to the cationic reagent formed from the aromatic divinyl compound (b 1) described later can be easily controlled _E Reaction and molecular design. More specifically, if the carbon atom having the largest HOMO electron density (shock modulus) among the carbon atoms in the benzene ring constituting the aromatic amine compound (a) is unsubstituted, the carbocation of the aromatic divinyl compound (b 1) as the cationic agent easily reacts with the carbon atom having the largest HOMO electron density. Thus, by controlling the number and position of alkyl groups attached to carbon atoms of the benzene ringThe position, etc., of the aromatic divinyl compound (b 1) can be adjusted. Therefore, it is presumed that the chemical structure or molecular chain length of the obtained second maleimide compound (A2) is easily designed.

For example, in the case where the aromatic amine compound (a) has an aniline skeleton having 1 benzene ring and 1 amino group, it is preferable that at least one carbon atom of the 2-, 4-and 6-positions of the aniline core is substituted with a hydrogen atom. Thus, the cationic reagent formed from the aromatic divinyl compound (b 1) described later is liable to attack carbon atoms in at least one of the 2-, 4-and 6-positions of the meta-and para-positions, which are the aniline nucleus, having a high electron density. In particular, if the aromatic amine compound (a) having an aniline nucleus with an alkyl group substituted at a specific position is used, the connection site with the aromatic divinyl compound (b 1) can be controlled approximately, and therefore the second maleimide compound (A2) having a uniform chemical structure or chain length can be easily obtained. For example, if 2, 6-dialkylamine is used as the aromatic amine compound (a), it is considered that the second maleimide compound (A2) linked to the aromatic divinyl compound (b 1) at the 4-position is obtained in large amount.

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 (for example, ethyl methylaniline in which either of the 2,3, 2,4, 2,6, 3,4 or 3,5 positions is methyl and the other is ethyl), cyclobutylaniline, cyclopentylaniline, cyclohexylaniline, o, m or p-methylaniline, o, m or p-ethylaniline, o, m or p-isopropylaniline, o, m or p-butylaniline, methyl isopropylaniline (e.g., methyl in either of the 2,3, 4, 2,6, 3,4 or 3,5 positions and isopropyl in the other) or ethyl butylaniline (e.g., ethyl butylaniline in either of the 2,3, 2,4, 2,6, 3,4 or 3,5 positions and butyl in the other), and the like. In addition, the above butyl group includes n-butyl, t-butyl and sec-butyl. The aromatic amine compound (a) in the present embodiment may be used alone or in combination of 2 or more.

For example, in the case where a maleimide group is directly bonded to a chemical structure of an unsubstituted benzene ring like N-phenylmaleimide, the state where the benzene ring and the 5-membered ring of maleimide are aligned on the same plane is stable, and therefore, they are easily stacked, and exhibit high crystallinity. Therefore, the solvent solubility is poor. In contrast, in the case of the present disclosure, for example, in the case where an alkyl group (for example, methyl group) is provided as a substituent for the benzene ring as in 2, 6-dimethylaniline, a 5-membered ring-twisted configuration of the benzene ring and maleimide is obtained due to steric hindrance of the methyl group, and stacking is difficult, and therefore crystallinity is reduced and solvent solubility is improved, which is a preferable mode. However, if the steric hindrance is too large, there is a concern that reactivity at the time of synthesis of maleimide is hindered, and therefore, for example, the aromatic amine compound (a) having an alkyl group having 1 to 6 carbon atoms is preferably used.

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

(in the above general formula (a), R ^1a Represents alkyl, p ^a An integer of 1 to 3. A plurality of R's are present ^1a May be the same or different. )

In the general formula (a), the alkyl group is preferably an alkyl group having 1 to 6 carbon atoms, 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 Preferably 1 or 2. R is as follows ^1a Where there are plural, they may be the same alkyl groups as each other or may be different alkyl groups.

In the present embodiment, the aromatic amine compound (a) represented by the general formula (a) may be used alone or in combination of 2 or more.

Aromatic divinyl Compound (b 1)

The aromatic divinyl compound (b 1) in the present embodiment has only 2 vinyl groups (CH) ₂ =ch-) (also referred to as vinyl. ) The substituent on the aromatic ring and the aromatic amine compound (a) can be reacted with each other, and the aromatic amine compound (a) can be used without particular limitation.

In the present embodiment, the reaction raw material (1) preferably contains a mixture of the aromatic divinyl compound (b 1) and the aromatic monovinyl compound (b 2).

Examples of the aromatic divinyl compound (b 1) include divinylbenzene, divinylbiphenyl, divinylnaphthalene, and an alkyl group, an alkoxy group, or an alkylthio group having 1 or more carbon atoms and having 1 to 10 carbon atoms substituted on the aromatic ring thereof; aryl, aryloxy or arylthio groups having 6 to 10 carbon atoms; cycloalkyl having 3 to 10 carbon atoms; a halogen atom; a hydroxyl group; or a mercapto group or the like. As a preferable embodiment of the substituent, R in the above general formula (1) ² The same applies to the above-described method. The alkyl group may be either a linear type or a branched type. Among them, the number of carbon atoms of the alkyl group or the alkoxy group is preferably 1 to 4 from the viewpoint of exhibiting the effect of high heat resistance. Specific examples of the alkyl group include methyl, ethyl, propyl, isopropyl, butyl, t-butyl, and isobutyl. Examples of the alkoxy group include methoxy, ethoxy, propoxy, and butoxy. Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.

The aromatic divinyl compound (b 1) as the reaction raw material (1) of the second maleimide compound (A2) of the present disclosure is preferably represented by the following formula (b 1).

(in the above general formula (b 1), R ^2b Independently represent an alkyl group having 1 to 10 carbon atoms, an alkoxy group or an alkylthio group; aryl, aryloxy or arylthio groups having 6 to 10 carbon atoms; cycloalkyl having 3 to 10 carbon atoms; a halogen atom; a hydroxyl group; or mercapto, q ^1b And represents an integer of 0 to 4. Q is as follows ^1b When the number is an integer of 2 or more, a plurality of R's are present ^2b May be the same as or different from each other. )

R in the above formula (b 1) ^2b Can correspond to R in the general formula (1) ² . Thus, R in the above general formula (b 1) ^2b Similarly to the general formula (1), each independently preferably 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 represents an alkyl group having 1 to 10 carbon atoms, and still more preferably represents an alkyl group having 1 to 6 carbon atoms.

In the above general formula (b 1), q ^1b Preferably 0 to 2. Q is as follows ^1b In the case of more than 2, a plurality of R's are present ^b1 May be the same groups as each other or may be different groups.

Specific examples of the aromatic divinylbenzene compound (b 1) of the present embodiment include divinylbenzene such as 1, 2-divinylbenzene, 1, 3-divinylbenzene, 1, 4-divinylbenzene, 2, 5-dimethyl-1, 4-divinylbenzene, 2, 5-diethyl-1, 4-divinylbenzene, cis, β, β' -diethoxy-m-divinylbenzene, 1, 4-divinyl-2, 5-dibutylbenzene, 1, 4-divinyl-2, 5-dihexylbenzene, 1, 4-divinyl-2, 5-dimethoxybenzene, and compounds composed of derivatives thereof; and divinyl naphthalenes such as 1, 3-divinyl naphthalene, 1, 4-divinyl naphthalene, 1, 5-divinyl naphthalene, 1, 6-divinyl naphthalene, 1, 7-divinyl naphthalene, 2, 3-divinyl naphthalene, 2, 6-divinyl naphthalene, 2, 7-divinyl naphthalene, 3, 4-divinyl naphthalene, 1, 8-divinyl naphthalene, 1, 5-dimethoxy-4, 8-divinyl naphthalene, and compounds composed of derivatives thereof, but are not limited thereto.

The aromatic divinyl compound (b 1) in the present embodiment may be used alone or in combination of 2 or more.

In particular, from the viewpoint of fluidity, as the aromatic divinylbenzene compound (b 1), divinylbenzene and a compound having a substituent on its aromatic ring are preferable, and divinylbenzene is more preferable. In the present embodiment, the substitution position of the vinyl group of divinylbenzene is not particularly limited, and a meta-form is preferable as the main component. The meta-position content in divinylbenzene is preferably 40 mass% or more, more preferably 50 mass% or more, relative to the total amount of divinylbenzene.

In this embodiment, the structural unit of the aromatic divinyl compound (b 1) is preferably contained in an amount of 10 to 90 mass%, more preferably 20 to 90 mass%, relative to the total amount (100 mass%) of the second maleimide compound (A2). The structural unit of the aromatic divinyl compound (b 1) is a group obtained by removing 2 hydrogen atoms (total of 4 hydrogen atoms) from each of 2 vinyl groups of the aromatic divinyl compound (b 1).

Aromatic monovinyl Compound (b 2)

The second maleimide compound (A2) in the present embodiment may further use other compounds as reaction raw materials in addition to the aromatic amine compound (a), the aromatic divinyl compound (b 1) and the maleic anhydride. Examples of the other compound include an aromatic monovinyl compound (b 2) having 1 vinyl group. That is, in the embodiment, it is preferable to use the aromatic amine compound (a), the aromatic divinyl compound (b 1), the aromatic monovinyl compound (b 2) and maleic anhydride as the reaction raw material (1). The second maleimide compound (A2) of the present embodiment is preferably a cured product of the second maleimide compound (A2) obtained by using an aromatic monovinyl compound (b 2) as a reaction raw material in addition to the aromatic amine compound (a), the aromatic divinyl compound (b 1) and the maleic anhydride, since the cured product is excellent in low dielectric loss tangent.

In addition, since the aromatic monovinyl compound (b 2) also generates a carbocation similarly to the aromatic divinyl compound (b 1), it is easy to react with a carbon atom having the maximum HOMO electron density (shock modulus) among carbon atoms in the aromatic hydrocarbon ring constituting the aromatic amine compound (a).

Examples of the aromatic monovinyl compound (b 2) in the present embodiment include vinylbenzene (styrene), vinylbiphenyl, vinylnaphthalene, and an alkyl group, an alkoxy group, or an alkylthio group having 1 or more carbon atoms and 1 to 10 substituted on the aromatic ring thereof; aryl, aryloxy or arylthio groups having 6 to 10 carbon atoms; cycloalkyl having 3 to 10 carbon atoms; a halogen atom; a hydroxyl group; or a mercapto group or the like. The alkyl group may be either a linear type or a branched type, and may have an unsaturated bond in the structure. In the case where low hygroscopicity is important, the alkyl group or the alkoxy group is preferably a group having 1 to 4 carbon atoms. Specific examples of the alkyl group include methyl, ethyl, propyl, isopropyl, butyl, t-butyl, and isobutyl. Examples of the alkoxy group include methoxy, ethoxy, propoxy, and butoxy. Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.

The aromatic monovinyl compound (b 2) which can be the reaction raw material (1) of the second maleimide compound (A2) of the present disclosure can be represented by the following general formula (b 2).

(in the above general formula (b 2), R ^9b Independently represent an alkyl group having 1 to 10 carbon atoms, an alkoxy group or an alkylthio group; aryl, aryloxy or arylthio groups having 6 to 10 carbon atoms; cycloalkyl having 3 to 10 carbon atoms; a halogen atom; a hydroxyl group; or mercapto, t ^1b An integer of 0 to 5. It is noted that t ^1b When the number is an integer of 2 or more, a plurality of R's are present ^9b May be the same as or different from each other. )

R in the above formula (b 2) ^9b Can correspond to R in the general formula (x) ⁹ . Thus, R in the above general formula (b 1) ^9b Similarly to the general formula (x), each independently preferably 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 represents an alkyl group having 1 to 10 carbon atoms, and still more preferably represents an alkyl group having 1 to 6 carbon atoms.

In the above general formula (b 1), t ^1b Preferably 1 to 4. It is noted that t ^1b In the case of more than 2, a plurality of R's are present ^9b May be the same groups as each other or may be different groups.

Specific examples of the aromatic monovinyl compound (b 2) of the present embodiment include vinylbenzenes such as styrene, fluorinated styrene, vinylbenzyl chloride, alkyl vinylbenzene (o-, m-, p-methylstyrene; o-, m-, p-ethylvinylbenzene), o-, m-, p- (chloromethyl) styrene, and compounds comprising derivatives thereof; biphenyl compounds such as 4-vinylbiphenyl, 4-vinyl-p-terphenyl, and compounds comprising derivatives thereof; and vinyl naphthalenes such as 1-vinyl naphthalene, 2-vinyl naphthalene, and compounds comprising derivatives thereof, but are not limited thereto.

In particular, from the viewpoint of obtaining a raw material, alkyl vinyl benzene and a compound having a substituent on an aromatic ring thereof are preferable, and ethyl vinyl benzene is more preferable.

The substitution positions of the vinyl group and the ethyl group of the ethylvinylbenzene are not particularly limited, and the meta-form is preferably used as a main component, and the content of the meta-form in the ethylvinylbenzene is more preferably 40 mass% or more, and further preferably 50 mass% or more, with respect to the total amount of the ethylvinylbenzene.

When the aromatic monovinyl compound (b 2) is used as the reaction raw material (1) of the second maleimide compound (A2) in the present embodiment, the molar ratio ((b 1)/(b 2)) of the aromatic monovinyl compound (b 2) to the aromatic divinyl compound (b 1) in the reaction raw material (1) is preferably 99/1 to 50/50, more preferably 98/2 to 70/30.

In this embodiment, the structural unit of the aromatic monovinyl compound (b 2) is preferably contained in an amount of 0 to 40% by mass, more preferably 0 to 30% by mass, relative to the total amount (100% by mass) of the second maleimide compound (A2). The structural unit of the aromatic monovinyl compound (b 2) is a group obtained by removing 2 hydrogen atoms from 1 vinyl group of the aromatic monovinyl compound (b 2).

Maleic anhydride-

In the present embodiment, maleic anhydride is an essential component of the reaction raw material (1) of the second maleimide compound (A2), and is used for reacting an amino group (including-NH) derived from the aromatic amine compound (a), as described in the column of the method for producing the second maleimide compound (A2) described later ₂ And substituted amino groups. ) Reaction of maleimido.

< preferred embodiment of the second maleimide Compound (A2) >

Hereinafter, a preferred mode of the second maleimide compound (A2) of the present disclosure will be described by taking a case where each aromatic ring is a benzene ring as an example. The following chemical formulas are used to exemplarily illustrate the present disclosure, and the scope of the present disclosure is not limited to the following chemical formulas.

In the present embodiment, the second maleimide compound (A2) is preferably represented by the following general formula (2).

(in the above general formula (2), R ¹ Each independently represents alkyl, 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, R ³ 、R ⁴ 、R ⁵ And R is ⁶ Each independently represents a hydrogen atom or a methyl group, and R ³ And R is ⁴ One of them is hydrogen atom and the other is methyl, R ⁵ And R is ⁶ One of which is a hydrogen atom and the other is a methyl group，

X ¹ Represents a substituent represented by the following general formula (x),

(in the general formula (x), R ⁷ And R is ⁸ Each independently represents a hydrogen atom or a methyl group, and R ⁷ And R is ⁸ One of them is hydrogen atom and the other is methyl, R ⁹ 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. )

M ²¹ Represents a hydrogen atom or a group represented by the following general formula (i), M ²² 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 is ⁸ Each independently represents a hydrogen atom or a methyl group, and R ⁷ And R is ⁸ One of which is a hydrogen atom and the other is a methyl group, t represents an integer from 0 to 4, and is bonded to another atom. When t is an integer of 2 or more, a plurality of R's are present ⁹ May be the same as or different from each other.]

[ in the above general formula (ii), R ¹ⁱⁱ Represents alkyl, p ⁱⁱ And represents an integer of 0 to 4. P is the same as ⁱⁱ When the number is an integer of 2 or more, a plurality of R's are present ¹ⁱⁱ Can be mutually connected withEither the same or different. In the above general formula (iii), R ¹ⁱⁱⁱ Represents alkyl, 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 is ⁸ Each independently represents a hydrogen atom or a methyl group, and R ⁷ And R is ⁸ One of which 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 For every 1 is connected with X ¹ The average value of substitution numbers of benzene rings of (a) represents a number of 1 to 4, and is connected with other atoms. P is the same as ⁱⁱⁱ When the number is an integer of 2 or more, a plurality of R's are present ¹ⁱⁱⁱ And when t is an integer of 2 or more, R is present in plural ⁹ May be the same as or different from each other.]

In the general formula (2), when p is an integer of 2 or more, a plurality of R's are present ¹ And when q is an integer of 2 or more, R's are present ² And when t is an integer of 2 or more, R is present in plural ⁹ May be the same as or different from each other. )

R in the above general formula (2) ¹ ～R ⁹ 、X ¹ The preferred modes of the above general formula (1) are the same as those of the above general formula (p, q, r, t) and k. Further, the general formula (i) corresponds to the general formula (x), R in the general formula (ii) ¹ⁱⁱ Corresponding to R in the above general formula (1) ¹ R in the above general formula (iii) ¹ⁱⁱⁱ Corresponding to R in the above general formula (1) ¹ 。

The number average molecular weight (Mn) of the second maleimide compound (A2) of the present disclosure is preferably in the range of 350 to 2,000, more preferably in the range of 400 to 1,500. The weight average molecular weight (Mw) of the second maleimide compound (A2) is preferably in the range of 400 to 500,000, more preferably in the range of 450 to 400,000.

In the second maleimide compound (A2) of the present disclosure, the molecular weight distribution (weight average molecular weight (Mw)/number average molecular weight (Mn)) calculated by Gel Permeation Chromatography (GPC) measurement is preferably in the range of 1.001 to 500, more preferably 1.001 to 400, from the viewpoint of excellent low dielectric constant and low dielectric loss tangent. In addition, according to the GPC diagram obtained by GPC measurement, when the molecular weight distribution is large across a wide range and the high molecular weight component is large, the proportion of the high molecular weight component contributing to flexibility is large, so that brittleness is suppressed as compared with a cured product using maleimide in the related art, and a cured product excellent in flexibility and softness can be obtained, which is a preferable aspect.

The number average molecular weight (Mn), the weight average molecular weight (Mw), and the molecular weight distribution (weight average molecular weight (Mw)/number average molecular weight (Mn)) of the second maleimide compound (A2) of the present embodiment were measured by gel permeation chromatography (hereinafter abbreviated as "GPC") under the measurement conditions described in examples described below.

In the case where the second maleimide compound (A2) 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 to the total amount (100% by mass) of the second maleimide compound (A2) is preferably 10% by mass or less, more preferably 5% by mass or less, still more preferably 3% by mass or less, still more 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 is ³³ R independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms ³⁴ Independently represent an alkyl group having 1 to 10 carbon atoms, an alkoxy group or an alkylthio group; aryl, aryloxy or arylthio groups having 6 to 10 carbon atoms; cycloalkyl having 3 to 10 carbon atomsThe method comprises the steps of carrying out a first treatment on the surface of the A halogen atom; a hydroxyl group; or mercapto, q ³ Represents an integer of 0 to 3, q ³ When the number is an integer of 2 or more, a plurality of R's are present ³⁴ May be the same or different from each other. In addition, represents a bond to other atoms. )

In the above general formula (3), R ³⁴ Preferably, 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 is ³¹ 、R ³² And R is ³³ Preferably a hydrogen atom or a methyl group.

< method for producing second maleimide Compound (A2)

Hereinafter, a method for producing the second maleimide compound (A2) of the present disclosure will be described.

The method for producing the second maleimide compound (A2) of the present embodiment is not particularly limited as long as it is produced using the aromatic amine compound (a), the aromatic divinyl compound (b 1) and maleic anhydride as the reaction raw materials (1), or as long as it has a structural unit represented by the above general formula (1). As an example of the method for producing the second maleimide compound (A2) of the present disclosure, for example, a production method comprising the following steps (1) and (2) can be cited.

Step (1): a step of reacting an aromatic amine compound (a) with an aromatic divinyl compound (b 1) as a reaction raw material (2) to obtain an intermediate amine compound (c) in the present embodiment;

step (2): and (c) reacting the intermediate amine compound (c) obtained in the step (1) with maleic anhydride as a reaction raw material (3) to obtain a second maleimide compound (A2) of the present disclosure.

Specifically, the method for producing the second maleimide compound (A2) of the present embodiment preferably includes a step (1) of reacting the aromatic amine compound (a) and the aromatic divinyl compound (b 1) with a solid acid catalyst (also referred to as a crosslinking step), and a step (2) of condensing the intermediate amine compound (c) produced in the step (1) with maleic anhydride (also referred to as a condensation step).

The steps of the method for producing the second maleimide compound (A2) of the present disclosure will be described in order.

Process (1): process for producing intermediate amine Compound (c) >

Hereinafter, a process for producing the intermediate amine compound (c) in this embodiment will be described.

The step (1) in the present embodiment is not particularly limited, and is, for example, a step of reacting the above-mentioned aromatic amine compound (a), the above-mentioned aromatic divinyl compound (b 1) (for example, divinylbenzene), and, if necessary, other compounds such as the aromatic monovinyl compound (b 2) (for example, ethylvinylbenzene) in the presence of an acid catalyst. Thereby, the intermediate amine compound (c) can be produced.

The proportion of the aromatic amine compound (a) to the aromatic divinyl compound (b 1) is preferably 0.1 to 10 moles, more preferably 0.2 to 3 moles, based on 1 mole of the aromatic amine compound (a), in view of the balance of physical properties of moldability and curability at the time of producing the resulting cured product. In the case of using the aromatic monovinyl compound (b 2) in combination, the molar ratio of the aromatic divinyl compound (b 1) to the total of the aromatic monovinyl compounds (b 2) is preferably 0.1 to 10 moles, more preferably 0.2 to 3 moles, relative to 1 mole of the aromatic amine compound (a).

In addition, as a specific method for carrying out the above reaction, it is common to charge all the raw materials together and directly react them at a predetermined temperature; or by charging the aromatic amine compound (a) and the acid catalyst, and reacting them while dropping the aromatic divinyl compound (b 1), other compounds (for example, the aromatic monovinyl compound (b 2)), and the like, while maintaining the temperatures at a predetermined temperature. In this case, the dropping time is usually 0.1 to 12 hours, preferably 6 hours or less. After the reaction, the solvent and the unreacted product are distilled off as needed in the case of using the solvent, and the unreacted product is distilled off in the case of not using the solvent, whereby the intermediate amine compound (c) as the target product can be obtained.

The acid catalyst used in step (1) of the present embodiment may be, for example, an inorganic acid such as phosphoric acid, hydrochloric acid, and sulfuric acid, an organic acid such as oxalic acid, benzenesulfonic acid, toluenesulfonic acid, methanesulfonic acid, and fluoromethanesulfonic acid, an activated clay, an acid clay, silica-alumina, a solid acid such as zeolite, and a strongly acidic ion exchange resin, or heteropolyhydrochloric acid, and it is preferable from the viewpoint of handling that the solid acid of the catalyst can be easily removed by filtration after the reaction, and when other acid is used, alkali-based neutralization and water-based washing are preferably performed after the reaction.

The amount of the acid catalyst to be blended is preferably 1 to 60 parts by mass in terms of handling property and economy, based on 100 parts by mass of the total amount of the raw materials to be added (the aromatic divinyl compound (b 1) or the mixture of the aromatic divinyl compound (b 1) and the aromatic monovinyl compound (b 2)) and the aromatic amine compound (a)). The reaction temperature is usually in the range of 100 to 270. DegreeC, preferably 100 to 220. DegreeC, in order to suppress the formation of the isomer structure and avoid side reactions such as thermal decomposition.

In the step (1) of the present embodiment, the reaction time of the mixture of the aromatic divinyl compound (b 1) or the aromatic divinyl compound (b 1) and the aromatic monovinyl compound (b 2) and the aromatic amine compound (a), that is, the crosslinking reaction time, is usually in the range of 1 to 48 hours under the above-mentioned reaction temperature conditions, and preferably in the range of 1 to 30 hours, since the reaction does not proceed completely in a short period of time, and side reactions such as thermal decomposition reaction of the product occur if the reaction time is long.

In the method for producing the intermediate amine compound (c) in the present embodiment, aniline or its derivative also serves as a solvent, and therefore, it is not necessary to use another solvent, but a solvent may be used. For example, in the case of carrying out the reaction using divinylbenzene as a raw material, the following method can be employed: the reaction is carried out at the above-mentioned reaction temperature range by using a solvent which can be azeotropically dehydrated such as toluene, xylene or chlorobenzene, azeotropically dehydrating the water contained in the catalyst, etc., if necessary, and then distilling off the solvent.

The intermediate amine compound (c) obtained in the step (1) preferably has a structural unit represented by the following general formula (4), for example.

(in the above general formula (4), R ¹ Each independently represents alkyl, R ² Independently represent an alkyl group having 1 to 10 carbon atoms, an alkoxy group or an alkylthio group; aryl, aryloxy or arylthio groups having 6 to 10 carbon atoms; cycloalkyl having 3 to 10 carbon atoms; a halogen atom; a hydroxyl group or a mercapto group,

X ¹ represents a substituent represented by the following general formula (x),

(in the general formula (x), R ⁷ And R is ⁸ Each independently represents a hydrogen atom or a methyl group, and R ⁷ And R is ⁸ One of them is hydrogen atom and the other is methyl, R ⁹ Alkyl is represented, and t is an integer of 0 to 4. )

In the general formula (4), when p is an integer of 2 or more, a plurality of R's are present ¹ May be the same as or different from each other. q is an integer of 2 or more, and a plurality of R's are present ² May be identical to each other or alsoMay be different. When t is an integer of 2 or more, a plurality of R's are present ⁹ May be the same as or different from each other.

R in the above general formula (4) ¹ ～R ⁹ 、X ¹ The preferred modes of the above general formula (1) are the same as those of the above general formula (p, q, r, t) and k. Further, as another preferable embodiment of the intermediate amine compound (c) obtained in the step (1), there is a structure in which the N-substituted maleimide group in the above general formula (2) is substituted with an amino group (including-NH 2 and a substituted amino group), which is also a preferable embodiment of the second maleimide compound (A2).

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

The measurement of the amine content of the intermediate amine compound (c) in the present specification is set to a value measured by a method according to the neutralization titration method defined in JIS K0070 (1992).

Process (2): maleimide >

The step (2) in the present embodiment is a step of reacting the intermediate amine compound (c) obtained in the step (1) with maleic anhydride. Amino groups (including-NH) of the amine compound (c) through an intermediate ₂ And substituted amino groups. ) The maleinization reaction is performed, and the chemical structure in which the above-described amino group is substituted with an N-substituted maleimide ring can be formed, and thus the second maleimide compound (A2) of the present disclosure can be obtained.

In this embodiment, the intermediate amine compound (c) represented by the general formula (4) obtained in the step (1) is charged into a reactor, dissolved in an appropriate 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 or the like, and the solvent is removed under reduced pressure, whereby the second maleimide compound (A2) as the target compound can be obtained. In addition, a dehydrating agent may be used in the reaction as required.

Examples of the organic solvent that can be used in step (2) of the present embodiment include ketones such as acetone, methyl Ethyl Ketone (MEK), methyl isobutyl ketone, cyclohexanone, and acetophenone; aprotic solvents such as N, N-dimethylformamide, N-dimethylacetamide, dimethylsulfoxide, N-methyl-2-pyrrolidone, acetonitrile, sulfolane, and the like; cyclic ethers such as dioxane and tetrahydrofuran; esters such as ethyl acetate and butyl acetate; aromatic solvents such as benzene, toluene and xylene may be used alone or in combination.

In the 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 the amino equivalent of maleic anhydride to the intermediate amine compound (c), more preferably 1 to 3 equivalents of maleic anhydride, and the mixture is reacted in an organic solvent in which the mass ratio of maleic anhydride to the total amount of the intermediate amine compound (c) and maleic anhydride is 0.1 to 10, preferably 0.2 to 5.

Examples of the catalyst that can be used in the step (2) of the present embodiment include inorganic salts such as acetates, chlorides, bromides, sulfates, and nitrates of nickel, cobalt, sodium, calcium, iron, lithium, and manganese; inorganic acids such as phosphoric acid, hydrochloric acid, and sulfuric acid; organic acids such as oxalic acid, benzenesulfonic acid, toluenesulfonic acid, methanesulfonic acid, fluoromethanesulfonic acid and the like; solid acids such as activated clay, acid clay, silica-alumina, zeolite, and strongly acidic ion exchange resins; heteropolyhydrochloric acid, etc., and toluene sulfonic acid is particularly preferably used.

Examples of the dehydrating agent used in step (2) of the present embodiment include lower aliphatic carboxylic anhydrides such as acetic anhydride, propionic anhydride, and butyric anhydride; oxides such as phosphorus pentoxide, calcium oxide, and barium oxide; inorganic acids such as sulfuric acid; porous ceramics such as molecular sieves, etc., acetic anhydride is preferably used.

The amount of the catalyst and the dehydrating agent that can be used in the step (2) of the present embodiment is not particularly limited, and generally, the catalyst and the dehydrating agent are used in combination with the amino group (-NH) of the intermediate amine compound (c) ₂ ) The catalyst may be used in an amount of 0.0001 to 1.0 mol, preferably 0.01 to 0.3 mol, and the dehydrating agent may be used in an amount of 1 to 3 mol, preferably 1 to 1.5 mol, based on 1 equivalent.

In the step (2) of the present embodiment, the reaction conditions for the maleimide may be such that the intermediate amine compound (c) and maleic anhydride are charged and reacted at a temperature ranging from 10 to 100 ℃, preferably from 30 to 60 ℃ for 0.5 to 12 hours, preferably from 1 to 4 hours, and then the catalyst is added and reacted at a temperature ranging from 90 to 130 ℃, preferably from 105 to 120 ℃ for 1 to 24 hours, preferably from 1 to 10 hours.

(curing agent (B))

The curable composition of the present embodiment may further contain a curing agent (B) within a range that does not impair the curing of the present invention. The curing agent (B) is preferably 2 mass% to 20 mass%, and most preferably 5 mass% to 10 mass%, based on 100 mass% of the total curable composition. When the content of the curing agent (B) is in the range of 5 mass% to 10 mass%, it is preferable from the viewpoint of low dielectric loss tangent.

Examples of the curing agent (B) of the present embodiment include amine compounds, cyanate compounds, amide compounds, acid anhydride compounds, phenol compounds, polyphenylene ether compounds, compounds having a substituent containing an unsaturated double bond, and diene polymers. These curing agents may be used alone or in combination of 2 or more.

Examples of the amine compound include diaminodiphenylmethane, diethylenetriamine, triethylenetetramine, diaminodiphenylsulfone, isophoronediamine, imidazole, and BF ₃ Amine complexes, guanidine derivatives, etc.

Examples of the cyanate ester compound include bisphenol a type cyanate ester resin, bisphenol F type cyanate ester resin, bisphenol E type cyanate ester resin, bisphenol S type cyanate ester resin, bisphenol sulfide type cyanate ester resin, phenyl ether type cyanate ester resin, naphthalene ether type cyanate ester resin, biphenyl type cyanate ester resin, tetramethylbiphenyl type cyanate ester resin, polyhydroxynaphthalene type cyanate ester resin, phenol novolac type cyanate ester resin, cresol novolac type cyanate ester resin, triphenylmethane type cyanate ester resin, tetraphenylethane type cyanate ester resin, dicyclopentadiene-phenol addition reaction type cyanate ester resin, phenol aralkyl type cyanate ester resin, naphthol phenol type cyanate ester resin, naphthol aralkyl type cyanate ester resin, naphthol-phenol copolyformal type cyanate ester resin, naphthol-cresol copolyformal type cyanate ester resin, aromatic hydrocarbon formaldehyde resin modified phenol resin type cyanate ester resin, biphenyl modified phenol type cyanate ester resin, anthracene type cyanate ester resin, and the like. These may be used alone or in combination of 2 or more kinds.

Examples of the amide compound include dicyandiamide, and polyamide resins synthesized from a dimer of linolenic acid and ethylenediamine.

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

Examples of the phenol-based compound include phenol novolac resins, cresol novolac resins, aromatic hydrocarbon formaldehyde resin-modified phenol resins, dicyclopentadiene phenol addition resins, phenol aralkyl resins (Zyloc resins), polyvalent phenol novolac resins synthesized from polyvalent hydroxyl compounds typified by resorcinol novolac resins and formaldehyde, naphthol aralkyl resins, trimethylol methane resins, tetraphenol ethane resins, naphthol novolac resins, naphthol-phenol copoly novolac resins, naphthol-cresol copoly novolac resins, biphenyl-modified phenol resins (polyvalent phenol compounds in which phenol cores are linked by a dimethylene group), biphenyl-modified naphthol resins (polyvalent phenol compounds in which phenol cores are linked by a dimethylene group), aminotriazine-modified phenol resins (polyvalent phenol compounds in which phenol cores are linked by a melamine group, benzoguanamine group, or the like), and polyvalent benzene compounds in which an aromatic ring-modified novolac resin containing an alkoxy group (polyvalent phenol compounds in which a phenol core and an aromatic ring containing an alkoxy group are linked by a formaldehyde).

The polyphenylene ether compound preferably has a structure represented by the following general formula (5) or (6), for example.

In the above general formulae (5) and (6), R ^d1 ～R ^d8 Examples of the "alkyl" include 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 alkoxycarbonyl group having 2 to 5 carbon atoms, an alkylcarbonyloxy group having 2 to 5 carbon atoms, and an alkylsulfonyl group having 1 to 5 carbon atoms. Examples of the terminal structure of the structures of the general formulae (5) and (6) include a structure having a group containing a hydroxyl group or a reactive double bond. 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 a methylthio group, an ethylthio group, a propylthio group, an isopropylthio group, a butylthio group, and a pentylthio group.

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

The alkoxycarbonyl group having 2 to 5 carbon atoms is not particularly limited, and examples thereof include a methyloxycarbonyl group, an ethyloxycarbonyl group, a propyloxycarbonyl group, an isopropyloxycarbonyl group, a butyloxycarbonyl group, and the like.

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

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

In this embodiment, R in the general formulae (5) and (6) is as follows ^d1 ～R ^d8 The compounds may be the same 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 a carbon atomThe alkyl group having 1 to 5 is more preferably a hydrogen atom, a methyl group or an ethyl group, and particularly preferably a hydrogen atom or a methyl group.

The Y in the above general formula (6) is a 2-valent aromatic group derived from an aromatic compound having 2 phenolic hydroxyl groups.

The aromatic compound having 2 phenolic hydroxyl groups is not particularly limited, and catechol, resorcinol, hydroquinone, 1, 4-dihydroxynaphthalene, 1, 5-dihydroxynaphthalene, 2, 6-dihydroxynaphthalene, 2, 7-dihydroxynaphthalene, 4' -biphenol, bisphenol a, bisphenol B, bisphenol BP, bisphenol C, bisphenol F, tetramethyl bisphenol a, and the like can be mentioned. Among these, hydroquinone, 2, 6-dihydroxynaphthalene, 2, 7-dihydroxynaphthalene, 4 '-biphenol, bisphenol A, bisphenol E, bisphenol F are preferable, and 4,4' -biphenol, bisphenol A, and tetramethyl bisphenol A are more preferable.

Further, since 2 phenolic hydroxyl groups of the aromatic compound having 2 phenolic hydroxyl groups form a phenethyl bond (2 oxygen atoms bonded to Y), Y becomes a 2-valent aromatic group derived from the aromatic compound having 2 phenolic hydroxyl groups. In other words, a group obtained by removing any 2 hydrogen atoms from the aromatic compound having 2 phenolic hydroxyl groups is referred to as "a 2-valent aromatic group derived from an aromatic compound having 2 phenolic hydroxyl groups".

The compound having a substituent containing an unsaturated double bond is not particularly limited as long as it has 2 or more substituents containing an unsaturated bond in the molecule, and examples of the substituent containing an unsaturated bond include compounds having an allyl group, an isopropenyl group, a 1-propenyl group, an acryl group, a methacryl group, a styryl group, a styrylmethyl group, and the like.

Examples of the diene polymer include unmodified diene polymers not modified with polar groups. Here, the polar group is a functional group that affects dielectric properties, and examples thereof include a phenol group, an amino group, an epoxy group, and the like. The diene polymer is not particularly limited, and for example, 1, 2-polybutadiene, 1, 4-polybutadiene, and the like can be used.

As the diene polymer, a homopolymer of butadiene having 50% or more of butadiene units in the polymer chain as a1, 2-bond and a derivative thereof can be used.

(other resin (C))

In addition, as long as the object of the present disclosure is not impaired, other resins (C) may be contained in addition to the first maleimide compound (A1) and the second maleimide compound (A2). As the other resin (C), bismaleimides, allyl ether compounds, allylamine compounds, triallyl cyanurate, alkenylphenol compounds, vinyl group-containing polyolefin compounds and the like, epoxy resins, phenol resins, active ester resins, polyphenylene ether resins, benzoxazine resins, styrene maleic anhydride copolymers, polybutadiene and its modified products, polyacetal resins, polyvinyl alcohol resins, liquid crystal polymers, fluorine resins, polystyrene, polyethylene, polyimide resins, thermosetting polyimide resins, silica gel, silicone oils and the like can be suitably blended in addition to the above-mentioned second maleimide compound (A2).

The content of the other resin (C) is preferably 2 mass% or more and 20 mass% or less, and most preferably 5 mass% or more and 10 mass% or less, with respect to 100 mass% of the total curable composition. When the content of the other resin (C) is in the range of 5 mass% to 10 mass%, it is preferable from the viewpoints of heat resistance and compatibility.

(curing accelerator)

The curable composition of the present embodiment may be optionally combined with a curing accelerator. As the curing accelerator, various substances can be used, and for example, a polymerization initiator such as an organic peroxide or an azo compound, a basic catalyst such as a phosphine compound or a tertiary amine is effective. Specific examples of the curing accelerator include benzoyl peroxide, dicumyl peroxide, azobisisobutyronitrile, triphenylphosphine, TPP-MK, TPP-K, triethylamine, and imidazoles. The curing accelerator may be used alone or in combination of 2 or more. The amount of the curing accelerator in the present embodiment is preferably 0.05 to 5% by mass based on the entire curable resin composition.

(additive)

The curable composition of the present embodiment may be optionally combined with an additive. Examples of the additives include silane coupling agents, mold release agents, pigments, emulsifiers, non-halogen flame retardants, inorganic fillers, flame retardants, solvents, and the like. The content of the additive is preferably 1 mass% or more and 20 mass% or less, and most preferably 3 mass% or more and 10 mass% or less, with respect to 100 mass% of the total curable composition.

Examples of the flame retardant include inorganic phosphorus flame retardants, organic phosphorus flame retardants, halogen flame retardants, and non-halogen flame retardants. In the curable composition of the present embodiment, a non-halogen flame retardant substantially containing no halogen atom is more preferably blended in order to exhibit flame retardancy within a range that does not impair the object. Examples of the non-halogen flame retardant include phosphorus flame retardants, nitrogen flame retardants, silicone flame retardants, inorganic flame retardants, and organic metal salt flame retardants, and these flame retardants may be used singly or in combination.

The curable composition of the present embodiment may contain an inorganic filler as needed. Examples of the inorganic filler include fused silica, crystalline silica, alumina, silicon nitride, and aluminum hydroxide. In particular, when the amount of the inorganic filler is increased, fused silica is preferably used. The fused silica may be used in the form of a crushed or spherical particle, and it is preferable to mainly use the spherical fused silica in order to increase the amount of the fused silica blended and to suppress the increase in melt viscosity of the molding material. Further, in order to increase the amount of the spherical silica, the particle size distribution of the spherical silica is preferably appropriately adjusted. The filling ratio is preferably high in view of flame retardancy, and is particularly preferably 30 mass% to 50 mass% with respect to the entire amount of the curable composition. In the case where the curable composition is used for the purpose of conductive paste and the like 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 first maleimide compound (A1) and the second maleimide compound (A2) is preferably 40 mass%, 42 mass%, 45 mass%, 47 mass%, 48 mass% or 50 mass% with respect to the entire curable composition (100 mass%). The upper limit of the total content is preferably 100 mass%, 99 mass%, 98 mass% or 97 mass%. The upper limit value and the lower limit value may be arbitrarily combined. Thus, for example, in the curable composition of the present embodiment, the total content of the first maleimide compound (A1) and the second maleimide compound (A2) is preferably 40 mass% or more and 100 mass% or less, the total content of the first maleimide compound (A1) and the second maleimide compound (A2) is more preferably 45 mass% or more and 100 mass% or less, and the total content of the first maleimide compound (A1) and the second maleimide compound (A2) is more preferably 50 mass% or more and 100 mass% or less, with respect to the entire curable composition (100 mass%).

In the curable composition of the present embodiment, the lower limit of the total content of the first maleimide compound (A1), the second maleimide compound (A2) and the inorganic filler is preferably 80 mass%, 82 mass%, 84 mass%, 86 mass% or 88 mass% with respect to the entire curable composition (100 mass%). The upper limit of the total content is preferably 100 mass%, 99 mass%, 98 mass% or 97 mass%. The upper limit and the lower limit may be arbitrarily combined, similarly to the range of the total content of the first maleimide compound (A1) and the second maleimide compound (A2).

In the curable composition of the present embodiment, the lower limit of the total content of the first maleimide compound (A1), the second maleimide compound (A2) and the additive is preferably 43 mass%, 45 mass%, 48 mass%, 50 mass% or 53 mass% with respect to the entire curable composition (100 mass%). The upper limit of the total content is preferably 100 mass%, 99 mass%, 98 mass% or 97 mass%. The upper limit and the lower limit may be arbitrarily combined, similarly to the range of the total content of the first maleimide compound (A1) and the second maleimide compound (A2).

[ cured product ]

The cured product of the present disclosure is preferably obtained from the curable composition. The cured product can be obtained by curing the curable composition. The curable composition can be obtained by uniformly mixing the above components (e.g., curing agent and compounding agent), and a cured product can be easily produced by the same method as the conventionally known method. Examples of the cured product include molded cured products such as laminates, castings, adhesive layers, coating films, and films.

The above-mentioned curing (heat curing) reaction can be easily performed even without a catalyst, but when a further rapid reaction is desired, it is effective to add a polymerization initiator such as an organic peroxide or an azo compound or a basic catalyst such as a phosphine compound or a tertiary amine. For example, benzoyl peroxide, dicumyl peroxide, azobisisobutyronitrile, triphenylphosphine, triethylamine, imidazoles, etc., and the amount of the curable resin composition is preferably 0.05 to 5% by mass.

[ Heat-resistant Material and electronic Material ]

The cured product obtained from the curable composition containing the first maleimide compound (A1) and the second maleimide compound (A2) of the present disclosure combines excellent low hygroscopicity and low dielectric properties, and thus can be suitably used for heat-resistant members or electronic members. In particular, the resin composition can be suitably used for prepregs, circuit boards, semiconductor sealing materials, semiconductor devices, laminated films, laminated substrates, adhesives using conductive pastes, resist materials, and the like. In addition, the resin composition can be suitably used as a matrix resin for a fiber-reinforced resin, and is particularly suitable as a prepreg having high heat resistance and a small dimensional change rate. In addition, the second maleimide compound (A2) contained in the curable composition exhibits excellent solubility in various solvents, and thus can be used as a coating material. The heat-resistant member and the electronic member thus obtained can be suitably used for various applications, and examples thereof include industrial machine parts, general machine parts, parts such as automobiles, railways, and vehicles, aerospace-related parts, electronic/electric parts, building materials, containers, packaging members, living goods, sports/leisure goods, and frame members for wind power generation, but are not limited to these.

Representative products (circuit boards, semiconductor sealing materials, semiconductor devices, prepregs, laminate substrates, laminate films, conductive pastes) produced using the curable resin composition of the present invention will be described below by way of example.

[ Circuit Board ]

The present disclosure is a circuit board as a laminate of the following prepreg and copper foil. As a method for obtaining a printed circuit board from the curable composition of the present embodiment, there is a method in which the above prepreg is laminated by a conventional method, copper foil is suitably laminated, and the laminate is heat-pressed at 170 to 300 ℃ under a pressure of 1 to 10MPa for 10 minutes to 3 hours.

[ semiconductor sealing Material ]

The present disclosure is a semiconductor sealing material containing the curable composition of the present embodiment. The semiconductor sealing material obtained using the curable composition of the present embodiment is preferable because the use of the first maleimide compound (A1) and the second maleimide compound (A2) of the present disclosure improves hygroscopicity and low dielectric loss tangent, and thus is excellent in processability, moldability and reflow resistance in the production process.

The curable composition of the present embodiment used for the semiconductor sealing material may contain an inorganic filler. The filling ratio of the inorganic filler may be, for example, in the range of 0.5 to 1200 parts by mass relative to 100 parts by mass of the curable composition of the present embodiment. Examples of the inorganic filler include barium sulfate, barium titanate, amorphous silica, crystalline silica, nonibao silica, fused silica, spherical silica, talc, clay, magnesium carbonate, calcium carbonate, alumina, aluminum hydroxide, silicon nitride, and aluminum nitride, as described above.

As a method for obtaining the semiconductor sealing material, there is a method in which the curable composition of the present embodiment is further sufficiently melt-mixed with an optional component curing accelerator and/or additive to be uniform using an extruder, kneader, roll, or the like as necessary. When the high thermal conductivity semiconductor sealing material for power transistors and power ICs is used, crystalline silica, alumina, silicon nitride, or other highly filled materials having higher thermal conductivity than fused silica, or fused silica, crystalline silica, alumina, silicon nitride, or the like can be used. The filler is preferably used in an amount of 30 to 95 parts by mass based on 100 parts by mass of the curable composition, and among them, 70 parts by mass or more, more preferably 80 parts by mass or more for improving flame retardancy, moisture resistance and solder crack resistance and reducing the linear expansion coefficient.

[ semiconductor device ]

The present disclosure is a semiconductor device including a cured product of the semiconductor sealing material. Since the semiconductor device obtained using the semiconductor sealing material obtained using the curable composition of the present embodiment uses the first maleimide compound (A1) and the second maleimide compound (A2) of the present disclosure, the semiconductor device has low viscosity and excellent fluidity, and further, the hygroscopicity, the elastic modulus at heat, and the adhesion to a metal material are improved, so that the processability, the moldability, and the reflow resistance in the manufacturing process are excellent, which is a preferable mode.

As a method for obtaining the semiconductor device, a method of molding the semiconductor sealing material by using a casting machine, a transfer molding machine, an injection molding machine, or the like, and further curing by heating at a temperature in the range of room temperature (20 ℃) to 250 ℃.

[ prepreg ]

The present disclosure is a prepreg comprising a reinforcing substrate and a prepreg impregnated with the curable composition of the present embodiment of the reinforcing substrate. As a method for obtaining a prepreg from the curable composition, there is a method in which a varnished curable composition is impregnated into a reinforcing substrate (paper, glass cloth, glass nonwoven fabric, aramid paper, aramid cloth, glass felt, glass yarn Shu Bu, etc.) by blending an organic solvent described later, and then the curable composition is half-cured (or uncured) by heating at a heating temperature corresponding to the type of solvent used, preferably 50 to 170 ℃. The mass ratio of the curable composition to the reinforcing base material used in this case is not particularly limited, and is preferably generally adjusted so that the resin content in the composition in the prepreg is 20 to 60 mass%.

In this embodiment, the semi-solid product of the curable composition is obtained by adjusting the heating temperature and the heating time, and stopping the curing reaction in the middle of the completion of the curing reaction. For example, the semi-solid compound may have a degree of solidification of 85% or less and 5% or more. On the other hand, the cured product in the present embodiment may have a higher degree of cure than the semi-cured product.

The degree of cure of the semi-cured product can be calculated from the following formula by measuring the amount of heat released by DSC when the curable composition is heated and the amount of heat released by the semi-cured product.

Curing degree (%) = [1- (curing exotherm of semi-cured product/curing exotherm of curable composition) ]×100

Examples of the organic solvent used in the production of the prepreg of the present embodiment include methyl ethyl ketone, acetone, dimethylformamide, methyl isobutyl ketone, methoxypropanol, cyclohexanone, methyl cellosolve, ethyl diglycol acetate, propylene glycol monomethyl ether acetate, and the like, and the selection and the appropriate amount to be used may be appropriately selected according to the application. The reinforcing base material used in the production of the prepreg according to the present embodiment is a woven fabric, nonwoven fabric, felt, paper, or the like composed of inorganic fibers such as glass fibers, polyester fibers, and polyamide fibers, or organic fibers, and these may be used alone or in combination.

The conditions for the heat treatment of the prepreg according to the present embodiment may be appropriately selected depending on the type and amount of the organic solvent, catalyst, and various additives used, and are usually conducted at a temperature of 80 to 220℃for 3 to 30 minutes.

[ laminated substrate ]

As a method for obtaining a laminated substrate from the curable composition of the present embodiment, a method that is subjected to the following steps 1 to 3 is exemplified. In step 1, the curable composition obtained by appropriately blending rubber, filler, and the like is first applied to a circuit board on which a circuit is formed by using a spray coating method, a curtain coating method, or the like, and then cured. In step 2, a predetermined hole such as a through hole is formed in the circuit board coated with the curable composition, and then the surface is treated with a roughening agent, and the surface is washed with hot water, whereby irregularities are formed on the board, and a metal such as copper is plated, if necessary. In step 3, the operations of steps 1 to 2 are sequentially repeated as desired, and the resin insulating layer and the conductor layer of the predetermined circuit pattern are alternately laminated, whereby the laminated substrate is molded. In the above step, the opening of the through-hole may be performed after the outermost resin insulation layer is formed. In the laminated substrate of the present embodiment, the resin-coated copper foil obtained by semi-curing the composition on the copper foil may be heat-pressed at 170 to 300 ℃ against the wiring board on which the circuit is formed, so that the roughened surface can be formed, and the plating process can be omitted, thereby producing the laminated substrate.

[ laminated film ]

The present disclosure is a laminate film containing the curable composition of the present embodiment. As a method for producing the laminated film of the present embodiment, the following method can be mentioned: the curable composition is applied to a support film (Y), and then dried to form a curable composition layer on the support film (Y), thereby producing an adhesive film for a multilayer printed wiring board.

When a laminate film is produced from a curable composition, it is important that the film is softened under the temperature conditions (usually 70 to 140 ℃) of lamination in a vacuum lamination method, and the film exhibits fluidity (resin flow) that enables resin filling in through holes or through holes existing in a circuit board, while laminating the circuit board, and the components are preferably blended so as to exhibit such characteristics. In the obtained laminate film and circuit board (copper-clad laminate, etc.), uniformity of appearance is required in order to exhibit a fixed performance at any position without occurrence of a phenomenon that local parts show different characteristic values due to phase separation or the like.

Here, the diameter of the through hole of the multilayer printed wiring board is usually 0.1 to 0.5mm, and the depth is usually 0.1 to 1.2mm, and it is generally preferable that the resin filling is possible in this range. When the circuit board is laminated on both sides, it is preferable to fill about 1/2 of the through hole.

Specifically, the method for producing the adhesive film can be produced by preparing the curable composition in the form of a varnish, coating the composition in the form of a varnish on the surface of the support film (Y), and drying the composition layer (X) composed of the curable composition by heating or blowing hot air or the like to dry the organic solvent. As the organic solvent, for example, ketones such as acetone, methyl ethyl ketone, and cyclohexanone are preferably used; acetate esters such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, and carbitol acetate; carbitols such as cellosolve and butyl carbitol; aromatic hydrocarbons such as toluene and xylene; dimethylformamide, dimethylacetamide, N-methylpyrrolidone, and the like, and is preferably used in a proportion of 30 to 60% by mass of nonvolatile components.

The thickness of the composition layer (X) formed is preferably equal to or greater than the thickness of the conductor layer. Since the thickness of the conductor layer of the circuit board is usually in the range of 5 to 70. Mu.m, the thickness of the resin composition layer is preferably 10 to 100. Mu.m. The composition layer (X) in the present embodiment may be protected by a protective film described later. By protecting with the protective film, adhesion of dust and the like on the surface of the resin composition layer, scratches can be prevented.

Examples of the support film (Y) and the protective film include polyolefin such as polyethylene, polypropylene, and polyvinyl chloride; polyesters such as polyethylene terephthalate (hereinafter, sometimes abbreviated as "PET"); examples of the polycarbonate, polyimide, and metal foil include release paper, copper foil, and aluminum foil. The support film and the protective film may be subjected to a mold release treatment in addition to the MAD treatment and the corona treatment. The thickness of the support film is not particularly limited, but is usually 10 to 150. Mu.m, and preferably 25 to 50. Mu.m. The thickness of the protective film is preferably 1 to 40. Mu.m.

The support film (Y) is peeled off after being laminated on a circuit board or after being cured by heating to form an insulating layer. If the support film (Y) is peeled off after the adhesive film is cured by heating, adhesion of dust or the like in the curing step can be prevented. When peeling is performed after curing, the support film is usually subjected to a release treatment in advance.

The multilayer printed wiring board can be manufactured from the laminate film obtained as described above. For example, when the resin composition layer (X) is protected by a protective film, after peeling them off, the resin composition layer (X) is laminated on one or both sides of the circuit board by, for example, vacuum lamination so that the resin composition layer (X) directly contacts the circuit board. The lamination may be carried out either batchwise or continuously by means of rolls. The laminate film and the circuit board may be heated (preheated) as needed before lamination, if necessary. Regarding the lamination conditions, the pressure bonding temperature (lamination temperature) is preferably set to 70 to 140℃and the pressure bonding pressure is preferably set to 1 to 11kgf/cm ² (9.8×10 ⁴ ～107.9×10 ⁴ N/m ² ) The lamination is preferably performed under reduced pressure of 20mmHg (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, a method of dispersing conductive particles in the composition can be cited. The conductive paste may be prepared into a paste resin composition for circuit connection or an anisotropic conductive adhesive according to the type of conductive particles used.

Examples (example)

The present invention is specifically described by examples and comparative examples, and "parts" and "%" below are based on mass unless otherwise specified. Physical properties of the synthesized second maleimide compound (A2) were measured as follows, and are shown in table 1.

(1) Amine equivalent weight

The amine equivalent of intermediate amine compound (c) was measured by the following measurement method.

In a 500mL Erlenmeyer flask with a stopper, about 2.5g of the intermediate amine compound (c), 7.5g of pyridine, 2.5g of acetic anhydride and 7.5g of triphenylphosphine were accurately weighed, and then a cooling tube was attached thereto, and the mixture was heated and refluxed in an oil bath set at 120℃for 150 minutes.

After cooling, 5.0mL of distilled water, 100mL of propylene glycol monomethyl ether, and 75mL of tetrahydrofuran were added, and the mixture was titrated by potentiometric titration with a 0.5mol/L potassium hydroxide-ethanol solution. Blank test was performed by the same method to correct.

Amine equivalent (g/equivalent) = (s×2,000)/(blank-a)

S: amount of sample (g)

A: consumption of 0.5mol/L Potassium hydroxide-ethanol solution (mL)

Blank: consumption of 0.5mol/L Potassium hydroxide-ethanol solution (mL) in blank test

(2) GPC measurement

The number average molecular weight (Mn), weight average molecular weight (Mw) and molecular weight distribution (Mw/Mn) of the second maleimide compound (A2) obtained in examples and comparative examples were calculated using the following measuring apparatus and measuring conditions.

"measuring device"

HLC-8320GPC manufactured by TOSOH Co., ltd "

"measurement conditions"

Column: the protective column "HXL-L" + TOSOH Co., ltd. "TSK-GELG2000HXL" + TOSOH Co., ltd. "TSK-GEL G3000HXL" + TOSOH Co., ltd. "TSK-GEL G4000 HXL") "

A detector: RI (differential refractometer)

And (3) data processing: TOSOH Co., ltd. "GPC WorkStation EcoSEC-workbench"

Measurement conditions: column temperature 40 DEG C

Developing solvent tetrahydrofuran

Flow rate 1.0 ml/min

Standard: according to the measurement manual of "GPC station EcoSEC-workbench", the following monodisperse polystyrene having a known molecular weight was used.

(use of polystyrene)

TOSOH Co., ltd. "A-500"

"A-1000" manufactured by TOSOH Co., ltd "

TOSOH Co., ltd. "A-2500"

TOSOH Co., ltd. "A-5000"

"F-1" manufactured by TOSOH Co., ltd "

"F-2" manufactured by TOSOH Co., ltd "

"F-4" manufactured by TOSOH Co., ltd "

"F-10" manufactured by TOSOH Co., ltd "

"F-20" manufactured by TOSOH Co., ltd "

"F-40" manufactured by TOSOH Co., ltd "

"F-80" manufactured by TOSOH Co., ltd "

"F-128" manufactured by TOSOH Co., ltd "

Sample: the tetrahydrofuran solution of the second maleimide compound (A2) obtained in the synthesis example was filtered with a microfilter to obtain (50. Mu.l) a 1.0 mass% tetrahydrofuran solution in terms of resin solid content.

(3) FD-MS measurement

The FD-MS chromatogram of the second maleimide compound (A2) obtained in the example was measured using the following measuring apparatus and measuring conditions.

Measurement device: JMS-T100GC AccuTOF

Measurement conditions

Measurement range: m/z=4.00-2000.00

Rate of change: 51.2mA/min

Final current value: 45mA

Cathode voltage: -10kV

Recording interval: 0.07sec

(4) ¹³ C-NMR measurement

The second maleimide Compound (A2) obtained in the example ¹³ The following measurement device for C-NMR chromatography,The measurement conditions were measured.

¹³ C-NMR: JEOL RESONANCE "JNM-ECZ400S"

Resonance frequency: 100MHz

Number of integration: 4000 times

Solvent: chloroform-d

Sample concentration: 12 mass%

Buffer reagent: chromium acetylacetonate (III)

(5) Synthesis of the second maleimide Compound (A2)

Synthesis example 1 Synthesis of polymaleimide Compound (X)

(I) Synthesis of intermediate amine Compound (c-1)

A flask equipped with a thermometer, a cooling tube, a Dean-Stark trap and a stirrer was charged with 242.4g (2.0 mol) of 2-ethylaniline, 242g of xylene and 80g of activated clay, and the mixture was stirred and heated to 130℃for 30 minutes. Then, 272.0g of DVB-810 (divinylbenzene/ethylstyrene=81/19 (mol)%), nitro iron chemical & materials) was added dropwise over 2 hours, and the mixture was reacted directly for 1 hour. Then, the temperature was raised to 190℃over 6 hours and maintained for 10 hours. After the reaction, air-cooled to 100 ℃, diluted with 300g of toluene, activated clay was removed by filtration, and low molecular weight substances such as solvents and unreacted substances were distilled off under reduced pressure to obtain an intermediate amine compound (c-1). The amine equivalent of the intermediate amine compound (c-1) was 214 g/equivalent.

(II) maleinization

A2L flask equipped with a thermometer, a cooling tube, a Dean-Stark trap and a stirrer was charged with 117.7g (1.2 mol) of maleic anhydride and 700g of toluene, and stirred at room temperature. Next, a mixed solution of 214g (1 equivalent) of the intermediate amine compound (c-1) and 175g of DMF was added dropwise over 1 hour, and then allowed to react for 2 hours. To this reaction solution, 37.1g of p-toluenesulfonic acid monohydrate was added, and the mixture was heated to 115℃to cool and separate water and toluene azeotroped under reflux, and then toluene alone was returned to the system to carry out dehydration reaction for 5 hours. After air cooling to room temperature, it was neutralized with 49% naoh. Then, distilled off under reduced pressure at 60 DEG C Toluene and water 600g of MEK (methyl ethyl ketone) was added to the DMF solution remaining in the flask. After the temperature of the solution was raised to 60 ℃, 200g of ion-exchanged water was used for 3 times of liquid separation treatment to remove salts in the solution. Further, sodium sulfate was added to dry, and then concentrated under reduced pressure, and the resultant reaction product was dried under vacuum at 80℃to obtain a polymaleimide compound (X) as a second maleimide compound (A2). The chemical structure and the characteristic analysis of the polymaleimide compound (X) are carried out by GPC, FD-MS and ¹³ C-NMR confirmation. The measurement results are shown in fig. 1A to 1C. Based on the GPC measurement result, the polymaleimide compound (X) had Mn of 998, mw of 367,834, and Mw/Mn of 368.697.

< examples 1 to 4 and comparative examples 1 to 4>

Preparation of curable composition and production of cured product

As the first maleimide compound (A1), a bismaleimide compound having an indane skeleton (represented by the following chemical formula (7) (n) and described in the maleimide compound A-1 described in Synthesis example 1 of patent No. 6797356, which is the first maleimide compound (1), was used ^A1 The number of the samples was =1.47, molecular weight distribution (Mw/Mn) =1.81)), first maleimide compound (2) ("BMI-1000" manufactured by Daikovia Kagaku Co., ltd. (chemical formula (8) below) first maleimide compound (3) ("BMI-5100" manufactured by Kagaku Kogyo Co., ltd. (chemical formula (9) below)).

The polymaleimide compound (X) obtained in synthesis example 1 was used as the second maleimide compound (A2).

The curable compositions of examples 1 to 4 and comparative examples 1 to 4 were prepared by blending the first maleimide compound (A1), the second maleimide compound (A2), and DCPO ("per my D", manufactured by daily oil corporation, dicumyl peroxide) as curing catalysts in the proportions shown in table 1 below.

Next, the curable compositions of examples 1 to 4 and comparative examples 1 to 4 were cured under the following curing conditions to prepare cured products corresponding to the curable compositions of examples 1 to 4 and comparative examples 1 to 4, respectively. The physical properties of dielectric loss tangent and glass transition temperature were evaluated by the following methods. The results are shown in Table 1.

< curing Condition >

After 2 hours at 200℃using a vacuum press, heat curing was performed at 250℃for 2 hours.

Thickness after molding: 1.3mm

Evaluation of dielectric constant and dielectric loss tangent

The dielectric constant (Dk) and dielectric loss tangent (Df) of the test piece after being completely dried and stored in a room at 23℃and 50% humidity for 24 hours were measured by a cavity resonance method using a network analyzer "E8362C" manufactured by Agilent technologies according to JIS-C-6481.

Glass transition temperature-

The cured products obtained by curing the curable compositions obtained in the present examples and comparative examples were cut into dimensions of 5mm in width and 54mm in length, and used as test pieces. The test piece was evaluated using a viscoelasticity measuring apparatus (DMA: solid viscoelasticity measuring apparatus "DMS6100" manufactured by Hitachi high technology Co., ltd., deformation mode: double-sided support bending, measuring mode: sine wave vibration, frequency 1Hz, heating rate 3 ℃/min) and the temperature at which the elastic modulus was most varied (tan. Delta. Variation rate was also the greatest) as the glass transition temperature (Tg (. Degree. C.).

TABLE 1

/>

From the results shown in table 1, it was confirmed that when examples 1 to 4 were compared with comparative examples 1 to 4, it was possible to form cured products having low dielectric loss tangent and high glass transition temperature and hardly causing cracking by using the curable compositions containing the first maleimide compound (A1) and the second maleimide compound (A2) of examples 1 to 4. It was also confirmed that by using the curable compositions containing the first maleimide compound (A1) and the second maleimide compound (A2) of examples 1 to 4, it was possible to form cured products having low dielectric loss tangent and high glass transition temperature even in the frequency band of Sub6 or more and being less likely to generate cracks.

[ Industrial applicability ]

According to the present disclosure, it is possible to provide a curable composition which is less likely to crack upon curing and which exhibits low dielectric characteristics and high glass transition temperature, and a cured product thereof.

Claims

1. A curable composition comprising a first maleimide compound (A1) and a second maleimide compound (A2) having a structural unit different from that contained in the first maleimide compound (A1),

the second maleimide compound (A2) is a compound having a maleimide group and a monocyclic or condensed polycyclic aromatic group to which 2 or more linear or branched alkylene groups are bonded.

2. The curable composition according to claim 1, wherein the second maleimide compound (A2) has a structural unit represented by the following general formula (1),

in the general formula (1), R ¹ Each independently represents an alkyl group,

X ¹ represents a substituent represented by the following general formula (x),

in the general formula (x), R ⁷ And R is ⁸ Each independently represents a hydrogen atom or a methyl group, and R ⁷ And R is ⁸ One of them is hydrogen atom and the other is methyl, R ⁹ Independently represent an alkyl group having 1 to 10 carbon atoms, an alkoxy group or an alkylthio group; aryl, aryloxy or arylthio groups having 6 to 10 carbon atoms; cycloalkyl having 3 to 10 carbon atoms; a halogen atom; a hydroxyl group; or mercapto, t represents an integer of 0 to 4,

r is X is connected to each 1 ¹ X of benzene ring of (B) ¹ The average value of the substitution numbers of (a) 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.

3. The curable composition according to claim 1 or 2, wherein the first maleimide compound (A1) is a bismaleimide compound.

4. The curable composition according to any one of claims 1 to 3, wherein the second maleimide compound (A2) is a polymaleimide compound.

5. A cured product of the curable composition according to any one of claims 1 to 4.

6. A prepreg comprising a reinforcing substrate and a prepreg impregnated with the curable composition according to any one of claims 1 to 4.

7. A circuit board comprising the prepreg according to claim 6 and a copper foil.

8. A laminated film comprising the curable composition according to any one of claims 1 to 4.

9. A semiconductor sealing material comprising the curable composition according to any one of claims 1 to 4.

10. A semiconductor device comprising the cured product of the semiconductor sealing material according to claim 9.