TWI906409B - Maleimide resins, asymmetric bismaleimide compounds, curing components, cured materials, semiconductor packaging materials, semiconductor packaging devices, prepregs, circuit boards, and additive films. - Google Patents

Abstract

This invention provides a maleimide resin or maleimide compound, a curable composition containing such a compound and its cured form, a semiconductor packaging material, a semiconductor packaging device, a prepreg, a circuit board, and a build-up film. The maleimide resin or maleimide compound is a maleimide derivative of a polyamine compound (C), which is a reaction product of multiple aromatic monoamine compounds (A) and a binder (B). These maleimide resins or maleimide compounds have low melting or softening points, excellent workability, and the cured form exhibits high heat resistance, making them suitable for use in semiconductor packaging materials, etc.

Description

Maleimide resins, asymmetric bismaleimide compounds, curing components, cured materials, semiconductor packaging materials, semiconductor packaging devices, prepregs, circuit boards, and additive films.

This invention relates to: maleimide resins or maleimide compounds with low melting or softening points, excellent workability, and high heat resistance in the cured form, suitable for use in semiconductor packaging materials, etc.; curable components containing these and their cured forms, semiconductor packaging materials, semiconductor packaging devices, prepregs, circuit boards, and build-up films.

Maleimide resins are being discussed for use in fields requiring extremely high heat resistance, such as power semiconductor packaging materials, due to their very high heat resistance in cured products. However, the high melting or softening point of currently available maleimide resins makes them difficult to work with as materials, which is a problem.

Regarding previously known maleimide resins, compounds of the 4,4'-diphenylmethane bismaleimide type are widely known; however, as mentioned earlier, these compounds have high melting points and poor workability as materials (see, for example, Patent 1). Furthermore, regarding maleimide resins with relatively high workability, compounds of the 2,2-bis[4-(4-maleimidephenoxy)phenyl]propane type are known; however, these compounds do not meet current market requirements in terms of heat resistance and other cured property properties (see, for example, Patent 2). [Prior Art Documents] [Patent Documents]

[Patent Document 1] Japanese Patent Application Publication No. 2-269716 [Patent Document 2] Japanese Patent Application Publication No. 6-128225

[The problem the invention aims to solve]

Therefore, the problem this invention aims to solve is to provide: maleimide resins or maleimide compounds with low melting or softening points, excellent workability, and high heat resistance in the cured form, suitable for use in semiconductor packaging materials, etc.; curable components containing these, the cured forms thereof, semiconductor packaging materials, semiconductor packaging devices, prepregs, circuit boards, and additive films. [Means for solving the problem]

The inventors conducted intensive research and discovered that maleimide resin obtained by maleimideation of polyamine compounds, which are the reaction products of multiple aromatic monoamine compounds and binders, has a low melting point or softening point, excellent workability, and the cured product has high heat resistance, making it suitable for use in semiconductor packaging materials, etc., thus completing this invention.

That is, the present invention relates to a maleimide resin, characterized in that it is a maleimide of a polyamine compound (C), which is a reaction product of a plurality of aromatic monoamine compounds (A) and a binding agent (B).

The present invention further relates to an asymmetric bismaleimine compound, which is a maleimide of an asymmetric diamine compound (C-1) formed by bonding two different aromatic monoamine compounds (A) together with a binder (B).

The present invention is further relating to a curable composition containing the aforementioned maleimide resin or the aforementioned asymmetric bismaleimide compound.

The present invention is further relating to a hardened form of the aforementioned hardening composition.

The present invention is further related to semiconductor packaging materials using the aforementioned curable components.

This invention is further relating to a semiconductor device using the aforementioned semiconductor packaging material.

The present invention further relates to prepregs using the aforementioned curing composition.

The present invention further relates to the use of the aforementioned prepreg circuit board.

This invention further relates to an extended film using the aforementioned curable composition. [Effects of the Invention]

According to the present invention, the following can be provided: maleimide resins or maleimide compounds with low melting or softening points, excellent workability, and high heat resistance in the cured form, suitable for use in semiconductor packaging materials, etc.; curable components containing such components and their cured forms, semiconductor packaging materials, semiconductor packaging devices, prepregs, circuit boards, and additive films.

[The form in which the invention is implemented]

The present invention will now be described in detail. The maleimide resin of the present invention is characterized by being a maleimide derivative of a polyamine compound (C), wherein the polyamine compound (C) is a reaction product of a plurality of aromatic monoamine compounds (A) and a binding agent (B).

The aforementioned aromatic monoamine compound (A) can be any compound having an _NH₂ group on its aromatic ring, with no particular limitation on other specific structures. Specifically, examples include compounds having an _NH₂ group on the aromatic ring of aromatic compounds such as benzene, naphthalene, and anthracene, or compounds having one or more other substituents in addition to the _NH₂ group. Examples of these other substituents include, for example, aliphatic hydrocarbons, alkoxy groups, alkenoxy groups, halogen atoms, aryl groups, aralkyl groups, and hydroxyl groups.

The aforementioned aliphatic hydrocarbons can be linear, branched, or cyclic structures, and may also contain unsaturated bonds in their structure. Specifically, examples include methyl, ethyl, vinyl, propyl, allyl, butyl, pentyl, hexyl, cyclohexyl, heptyl, octyl, and nonyl. Examples of alkoxy groups include methoxy, ethoxy, propyloxy, and butoxy. Examples of alkenoxy groups include allyloxy. Examples of halogen atoms include fluorine, chlorine, and bromine. Examples of aryl groups include phenyl, naphthyl, anthracene, and structural sites on which the aforementioned aliphatic hydrocarbons or alkoxy or halogen atoms are substituted. The aforementioned aryl groups include benzyl, phenylethyl, naphthylmethyl, naphthylethyl, and structural sites on which the aforementioned alkyl or alkoxy, halogen atoms, etc., are substituted.

Among the aforementioned aromatic monoamine compounds (A), those resulting in maleimide resins with low melting or softening points and excellent workability are preferably aniline or compounds having one or more of the aforementioned other substituents on the aromatic nucleus of aniline. Furthermore, aniline, compounds having a substituent at the 2-position of aniline, and compounds having substituents at the 2,6-positions of aniline are particularly preferred. Moreover, regarding the type of substituents in compounds having a substituent at the 2-position of aniline and compounds having substituents at the 2,6-positions of aniline, for the purpose of forming maleimide resins with excellent heat resistance in the cured form, aliphatic hydrocarbons with 1 to 4 carbon atoms are preferred, and alkyl groups with 1 to 4 carbon atoms are even more preferred.

In this invention, multiple aromatic monoamine compounds (A) are used together. This results in a maleimide resin that maintains the characteristics of a maleimide resin, exhibiting high heat resistance, low melting or softening point, and excellent workability. The number of aromatic monoamine compounds (A) used is multiple; that is, two or more are acceptable, with no particular upper limit. However, for ease of manufacturing, using two to five compounds is preferable, and using two or three together is even better. Furthermore, the amount of each aromatic monoamine compound (A) used, in order to fully utilize the effects of low melting or softening point and excellent workability, is preferably at least 10% by mass, and more preferably 25% by mass, relative to the total amount of the aforementioned aromatic monoamine compounds (A). Furthermore, regarding its upper limit, it is preferably below 90%, more preferably below 75%. Regarding the aforementioned aromatic monoamine compound (A), when two compounds are used together, the mass ratio of the two is preferably in the range of 10/90 to 90/10. More preferably, it is in the range of 20/80 to 80/20.

The aforementioned binding agent (B) is a compound that can react with the aforementioned aromatic monoamine compound (A) to bond the aromatic rings of the aforementioned aromatic monoamine compound (A) together. Its specific structure is not particularly limited, and various compounds can be used. Furthermore, the aforementioned binding agent (B) can be used alone or in combination with two or more. Specific examples of the aforementioned binding agent (B) include aldehyde compounds (B-1), ketone compounds (B-2), aromatic compounds represented by the following general formula (B-3) (B-3), aromatic compounds represented by the following general formula (B-4) (B-4), aromatic compounds represented by the following general formula (B-5) (B-5), aromatic compounds represented by the following general formula (B-6) (B-6), aromatic compounds represented by the following general formula (B-7) (B-7), and aromatic compounds represented by the following general formula (B-8) (B-8).

[In general formulas (B-3) to (B-8), Ar ¹ is independent and represents an aromatic ring that may have substituents; R ¹ is independent and is a hydrogen atom or a methyl group; R ² is independent and is a hydrogen atom or an aliphatic hydrocarbon with 1 to 4 carbon atoms; R ³ is independent and is any one of an aliphatic hydrocarbon, alkoxy group, alkenoxy group, alkynoxy group, halogen atom, aryl group, or aralkyl group; l is an integer from 0 to 3; X is any one of a hydroxyl group, halogen atom, or alkoxy group; Y is a single bond, a divalent aliphatic hydrocarbon with 1 to 6 carbon atoms, an oxygen atom, a sulfur atom, or a sulfonylurate group.]

The aforementioned aldehyde compounds (B-1) include, for example, aliphatic aldehyde compounds such as formaldehyde or acetaldehyde; and aromatic aldehyde compounds such as benzaldehyde or naphthaldehyde. One of these may be used alone, or two or more may be used together.

The aforementioned ketone compounds (B-2) include, for example, aliphatic ketone compounds such as acetone, methyl ethyl ketone, and diethyl ketone; and aromatic ketone compounds such as acetobenzene. One of these may be used alone, or two or more may be used together.

In the aforementioned general formulas (B-3) to (B-6), Ar ¹ stands independently, representing an aromatic ring that may have substituents. Specifically, examples include phenyl, naphthyl, and structural sites having one or more various substituents on such aromatic rings. Regarding the aforementioned substituents, examples include aliphatic hydrocarbons, alkoxy groups, alkenyloxy groups, halogen atoms, aryl, aralkyl, hydroxyl, etc. The aforementioned aliphatic hydrocarbons can be any of linear, branched, or cyclic structures, and may also have unsaturated bonds in the structure. Specifically, examples include methyl, ethyl, vinyl, propyl, allyl, butyl, pentyl, hexyl, cyclohexyl, heptyl, octyl, nonyl, etc. The aforementioned alkoxy groups include methoxy, ethoxy, propyloxy, butoxy, etc. The aforementioned olefinic groups include, for example, allyloxy. The aforementioned halogen atoms include, for example, fluorine, chlorine, and bromine. The aforementioned aryl groups include, for example, phenyl, naphthyl, anthracene, and structural sites on which the aromatic nucleus is substituted by the aforementioned aliphatic hydrocarbon or alkoxy group, halogen atom, etc. The aforementioned aralkyl groups include, for example, benzyl, phenylethyl, naphthylmethyl, naphthylethyl, and structural sites on which the aromatic nucleus is substituted by the aforementioned alkyl or alkoxy group, halogen atom, etc.

In the aforementioned general formulas (B-4) and (B-6), ^R2 is independent and is either a hydrogen atom or an aliphatic hydrocarbon with 1 to 4 carbon atoms. The aforementioned aliphatic hydrocarbons with 1 to 4 carbon atoms can be linear, branched, or cyclic structures, and may also contain unsaturated bonds in their structure. Specifically, examples include methyl, ethyl, vinyl, propyl, allyl, and butyl.

In the aforementioned general formulas (B-7) and (B-8), ^R3 is independent and can be any one of an aliphatic hydrocarbon, alkoxy group, alkenoxy group, alkynoxy group, halogen atom, aryl group, or aralkyl group, and l is an integer from 0 to 3. The aforementioned aliphatic hydrocarbon can be any of a linear, branched, or cyclic structure, and may also have unsaturated bonds in its structure. Specifically, examples include methyl, ethyl, vinyl, propyl, allyl, butyl, pentyl, hexyl, cyclohexyl, heptyl, octyl, and nonyl. Examples of alkoxy groups include methoxy, ethoxy, propyloxy, and butoxy. Examples of alkenoxy groups include allyloxy. Examples of halogen atoms include fluorine, chlorine, and bromine atoms. The aforementioned aryl groups include phenyl, naphthyl, anthracene, and structural sites on which the aromatic nucleus is substituted by the aforementioned aliphatic hydrocarbon, alkoxy group, halogen atom, etc. The aforementioned aralkyl groups include benzyl, phenylethyl, naphthylmethyl, naphthylethyl, and structural sites on which the aromatic nucleus is substituted by the aforementioned alkyl, alkoxy group, halogen atom, etc.

In the aforementioned general formulas (B-4), (B-6), and (B-8), X is any one of a hydroxyl group, a halogen atom, or an alkoxy group. Examples of alkoxy groups include methoxy, ethoxy, propyloxy, and butoxy.

In the aforementioned general formulas (B-5) and (B-6), Y is any one of a single bond, a divalent aliphatic hydrocarbon with 1 to 6 carbon atoms, an oxygen atom, a sulfur atom, or a sulfonyl group. The aforementioned divalent aliphatic hydrocarbon with 1 to 6 carbon atoms can be any of a linear, branched, or cyclic structure, and may also have unsaturated bonds in the structure.

The reaction steps for reacting the aforementioned aromatic monoamine compound (A) with the aforementioned binding agent (B) to obtain a polyamine compound (C) can be exemplified by methods such as reacting multiple of the aforementioned aromatic monoamine compounds (A) with the aforementioned binding agent (B) under acidic catalytic conditions. In particular, from the perspective of ease of reaction control, it is preferable to add the aforementioned binding agent (B) to the aforementioned aromatic monoamine compound (A) in portions. The reaction can also be carried out in a suitable solvent. Furthermore, heating to approximately 50–200°C can efficiently facilitate the reaction. After the reaction is completed, washing with an alkaline aqueous solution or distilled water, etc., yields the intermediate polyamine compound (C).

The aforementioned acidic catalysts include, for example, p-toluenesulfonic acid, dimethylsulfuric acid, diethylsulfuric acid, sulfuric acid, hydrochloric acid, oxalic acid, and activated clay. One of these can be used alone, or two or more can be used together. The amount of the aforementioned acidic catalyst added, relative to 2 moles of the aforementioned aromatic monoamine compound (A), is preferably in the range of 0.01 to 0.5 moles, more preferably in the range of 0.1 to 0.3 moles. When the mole number cannot be defined, the proportion relative to the total amount of aniline compound (A), binder (B), solvent, and acidic catalyst is preferably in the range of 1 wt% to 50 wt%.

The aforementioned solvents include, for example, distilled water, toluene, xylene, and other organic solvents. These can be used alone or in mixtures of two or more solvents. The amount of the aforementioned solvent used is preferably in the range of 5% to 100% by mass relative to the total mass of the aforementioned aromatic monoamine compound (A) and the aforementioned binding agent (B).

The maleimide reaction of the aforementioned polyamine compound (C) can be described, for example, by reacting the aforementioned polyamine compound (C) with an acid anhydride under acidic catalytic conditions. In particular, for ease of reaction control, it is preferable to add the aforementioned acid anhydride to the aforementioned polyamine compound (C) in portions, or to dissolve the aforementioned acid anhydride in a suitable solvent and add it dropwise. The reaction can also be carried out in a suitable solvent. For a more preferred reaction sequence, the aforementioned polyamine compound (C) and the aforementioned acid anhydride are first stirred at room temperature to obtain an amic acid intermediate. Then, an acidic catalyst is added, and the mixture is heated at 50–200°C, more preferably 70–150°C, to allow the reaction to proceed. At this time, it is preferable to remove moisture from the system. After the reaction is complete, the desired maleimide resin can be obtained by washing with an alkaline solution or distilled water.

The aforementioned anhydrides include, for example, maleic anhydride, leuconic anhydride, and 2,3-dimethylmaleic anhydride. One of these may be used alone, or two or more may be used together.

The aforementioned acidic catalysts include, for example, p-toluenesulfonic acid, hydroxy-p-toluenesulfonic acid, methanesulfonic acid, sulfuric acid, and phosphoric acid. One of these can be used alone, or two or more can be used together. The amount of the aforementioned acidic catalyst added, relative to the amino equivalent of 1 g/mol of the aforementioned polyaniline compound (C), is typically 0.01 to 10 mol, preferably 0.03 to 3 mol.

The aforementioned solvent may be any solvent capable of dissolving the aforementioned polyamine compound (C) or the aforementioned acid anhydride. In particular, considering the high solubility of the aforementioned polyamine compound (C) or the aforementioned acid anhydride and the efficient conduct of the reaction, a mixed solvent of a non-polar solvent such as toluene and an aprotic polar solvent such as dimethylformamide is preferred. Besides toluene, the aforementioned non-polar solvents may include xylene and chlorobenzene. Furthermore, besides dimethylformaldehyde, the aforementioned aprotic polar solvents may include methyl ethyl ketone. The mixing ratio of the two and the amount of solvent used can be appropriately adjusted according to the solvent solubility of the aforementioned polyamine compound (C) or the aforementioned acid anhydride. For example, the following method can be used: the mass ratio of the aforementioned nonpolar solvent and aprotic solvent is set to be in the range of 1/99 to 99/1, and the total amount of solvent is set to be in the range of 0.5% to 80% relative to the total amount of the aforementioned polyamine compound (C), the aforementioned acid anhydride and the total amount of solvent.

The molecular weight of the maleimide resin of this invention is not particularly limited, and can be adjusted to a better value by changing the appropriate reaction conditions according to the application. In the case of use in semiconductor packaging materials, in order to become a resin that maintains the high heat resistance of the cured product, while also having a low melting point or softening point and good workability, it is preferable to contain components with relatively low molecular weight, such as 2-nucleated components represented by formula (1), 3-nucleated components represented by formula (2), or 4-nucleated components represented by formula (3-1) or (3-2).

[In the formula, A is a structural site derived from the aforementioned aromatic monoamine compound (A) and possessing a maleicimine group; B is a structural site derived from the aforementioned binding agent (B); A and B in the formula may be the same as or different from each other.]

In particular, maleimide resins containing dinuclear components (bismaleimide compounds) are preferred. The proportion of dinuclear components (bismaleimide compounds) in maleimide resins is preferably 30% or more, and even more preferably 50% or more.

In this invention, the content of 2 nuclei in the maleimine resin is calculated from the area ratio of a gel osmosis chromatography (GPC) chart. Furthermore, in this invention, the determination conditions for gel osmosis chromatography (GPC) are as described in the embodiments. Moreover, in this invention, the "number of nuclei," as shown in the aforementioned formulas (1) to (3-2), refers to the number of structural sites in the molecule originating from the aforementioned aromatic monoamine compound (A).

Furthermore, among the two core components (bismaleimide compounds), considering the need to maintain high heat resistance in the hardened material while having a low melting or softening point and excellent workability, an asymmetric bismaleimide compound is preferred. This asymmetric bismaleimide compound is a maleimide derivative of an asymmetric diamine compound (C-1) formed by the bonding of two different aromatic monoamine compounds (A) through a binder (B). Moreover, it is preferable to use an aniline compound as the aforementioned aromatic monoamine compound (A), and even more preferable is an asymmetric bismaleimide compound represented by the following structural formula (4). In this invention, the asymmetric maleimide compound can also be purified and used separately.

[In the formula, Z is a divalent organic group with 1 to 200 carbon atoms; ^R4 is independent and can be any one of aliphatic hydrocarbon, alkoxy, alkenoxy, alkynoxy, halogen, aryl, or aralkyl. When there are multiple ^R4s in the formula, they can be the same or different; m is an integer from 0 to 4; the structural sites α and β enclosed by the dashed lines have different structures.]

In the aforementioned structural formula (4), Z is a structural site derived from the aforementioned binder (B). Z is a divalent organic group with 1 to 200 carbon atoms; however, as long as the number of carbon atoms is in the range of 1 to 200, it can also be a structural site containing other atoms such as oxygen atoms or halogen atoms. Among these, a divalent organic group with 1 to 20 carbon atoms is preferred. For specific examples of Z, the structural sites represented by the following general formulas (Z-1) to (Z-8) can be listed, for example.

[In general formulas (Z-1) to (X-8), ^Ar1 is independent and represents an aromatic ring that may have substituents; ^R3 is independent and is any one of an aliphatic hydrocarbon, alkoxy, alkenoxy, alkynoxy, halogen atom, aryl, or aralkyl; l is an integer from 0 to 3; ^R5 is independent and represents a hydrogen atom, an aliphatic hydrocarbon with 1 to 4 carbon atoms, or an aromatic ring that may have substituents; ^R6 is independent and represents a hydrogen atom or an aliphatic hydrocarbon with 1 to 4 carbon atoms; ^R7 is any divalent aliphatic hydrocarbon other than those represented in general formula (Z-1), an aromatic group that may have substituents, or any combination thereof; Y is a single bond, any one of a divalent aliphatic hydrocarbon with 1 to 6 carbon atoms, an oxygen atom, a sulfur atom, or a sulfonylurate group; n is an integer greater than or equal to 1.]

In the aforementioned general formula (Z-1), each R ⁵ stands independently, representing a hydrogen atom, an aliphatic hydrocarbon with 1 to 4 carbon atoms, or an aromatic ring that may have substituents. The aforementioned aliphatic hydrocarbon with 1 to 4 carbon atoms can be any of a linear, branched, or cyclic structure, and may also have unsaturated bonds in the structure. Specifically, examples include methyl, ethyl, vinyl, propyl, allyl, and butyl. The aforementioned aromatic rings that may have substituents include, for example, phenyl, naphthyl, and structural sites having one or more various substituents on such aromatic rings. Regarding the aforementioned substituents, examples include aliphatic hydrocarbons, alkoxy groups, alkenoxy groups, halogen atoms, aryl groups, aralkyl groups, and hydroxyl groups. The aforementioned aliphatic hydrocarbons can be linear, branched, or cyclic structures, and may also contain unsaturated bonds. Specifically, examples include methyl, ethyl, vinyl, propyl, allyl, butyl, pentyl, hexyl, cyclohexyl, heptyl, octyl, and nonyl. Examples of alkoxy groups include methoxy, ethoxy, propyloxy, and butoxy. Examples of alkenoxy groups include allyloxy. Examples of halogen atoms include fluorine, chlorine, and bromine. Examples of aryl groups include phenyl, naphthyl, anthracene, and structural sites on these aromatic nuclei that are substituted by the aforementioned aliphatic hydrocarbons, alkoxy groups, or halogen atoms. The aforementioned aryl groups may include benzyl, phenylethyl, naphthylmethyl, naphthylethyl, and structural sites on these aromatic nuclei that are substituted by the aforementioned alkyl or alkoxy, halogen atoms, etc.

In the aforementioned general formulas (Z-2), (Z-3), and (Z-8), Ar ¹ stands independently, representing an aromatic ring that may have substituents. Specific examples can be listed that are the same as Ar ¹ in the aforementioned general formulas (B-3) to (B-6).

In the aforementioned general formulas (Z-2) and (Z-3), ^R6 stands independently, representing a hydrogen atom or an aliphatic hydrocarbon with 1 to 4 carbon atoms. These aliphatic hydrocarbons with 1 to 4 carbon atoms can be linear, branched, or cyclic structures, and may also contain unsaturated bonds. Specifically, examples include methyl, ethyl, vinyl, propyl, allyl, and butyl.

In the aforementioned general formula (Z-3), Y can be any of a single bond, a divalent aliphatic hydrocarbon with 1 to 6 carbon atoms, an oxygen atom, a sulfur atom, or a sulfonyl group. The aforementioned divalent aliphatic hydrocarbon with 1 to 6 carbon atoms can be any of a linear, branched, or cyclic structure, and can also have unsaturated bonds in the structure.

In the aforementioned general formula (Z-4), each ^R3 is independent and is any one of aliphatic hydrocarbon, alkoxy, alkenoxy, alkynoxy, halogen atom, aryl, or aralkyl; l is an integer from 0 to 3. Specific examples can be listed that are the same as ^R3 in the aforementioned general formulas (B-7) and (B-8).

In the aforementioned general formula (Z-7), R ⁷ can be any divalent aliphatic hydrocarbon other than that represented by general formula (Z-1), an aromatic hydrocarbon that may have substituents, or any combination thereof. The aforementioned divalent aliphatic hydrocarbon may be any of a linear, branched, or cyclic structure, and may also have unsaturated bonds in its structure.

In the aforementioned structural formula (4), each ^R4 is independent and can be any one of an aliphatic hydrocarbon, alkoxy group, alkenoxy group, alkynoxy group, halogen atom, aryl group, or aralkyl group. The aforementioned aliphatic hydrocarbon can be any of a linear, branched, or cyclic structure, and may also have unsaturated bonds in the structure. Specifically, examples include methyl, ethyl, vinyl, propyl, allyl, butyl, pentyl, hexyl, cyclohexyl, heptyl, octyl, and nonyl. Examples of alkoxy groups include methoxy, ethoxy, propyloxy, and butoxy. Examples of alkenoxy groups include allyloxy. Examples of halogen atoms include fluorine, chlorine, and bromine atoms. The aforementioned aryl groups include phenyl, naphthyl, anthracene, and structural sites on which the aromatic ring is substituted by the aforementioned aliphatic hydrocarbon, alkoxy group, halogen atom, etc. The aforementioned aralkyl groups include benzyl, phenylethyl, naphthylmethyl, naphthylethyl, and structural sites on which the aromatic ring is substituted by the aforementioned alkyl group, alkoxy group, halogen atom, etc. In the formula, ^R4 can be a plurality of elements, which may be the same or different.

In order to obtain a maleimide resin with a low melting point or softening point and good workability, it is preferable that one or both of the carbon atoms adjacent to the carbon atom substituted with the maleimide group have substituents. Furthermore, the substituent is preferably an aliphatic hydrocarbon group with 1 to 4 carbon atoms, and more preferably an alkyl group with 1 to 4 carbon atoms.

The curing composition of this invention contains the aforementioned maleimide resin or the aforementioned asymmetric bismaleimide compound. The curing composition of this invention may use the aforementioned maleimide resin or the aforementioned asymmetric bismaleimide compound alone as the curing component, or may use one or more other curing compounds in combination.

Other curing compounds mentioned above include, for example, epoxy resins, phenolic resins, amine compounds, active ester resins, cyanate ester resins, benzo[a]pyrene resins, and compounds containing unsaturated bonds.

The aforementioned epoxy resins include, for example, various bisphenol-type epoxy resins, various biphenyl-type epoxy resins, various phenolic varnish-type epoxy resins, dicyclopentadiene-phenol addition reaction epoxy resins, and phenolic alkyl-type epoxy resins. One of these may be used alone, or two or more may be used together.

The aforementioned phenolic resins include, for example, various bisphenols, various biphenyls, various phenolic varnish resins, dicyclopentadiene-phenol addition reaction resins, phenolic aralkyl resins, and various propyne ether resins. One of these may be used alone, or two or more may be used together.

The curing composition of this invention may, as needed, contain various additives such as curing accelerators, flame retardants, inorganic fillers, silane coupling agents, mold release agents, pigments, and emulsifiers.

The aforementioned curing accelerators include, for example, phosphorus compounds, peroxides, tertiary amines, imidazole compounds, pyridine compounds, organic acid metal salts, Lewis acids, and amine salts. Among these, from the perspective of excellent curing properties, heat resistance, electrical properties, and moisture resistance reliability, triphenylphosphine is preferred among phosphorus compounds, diisopropylphenyl peroxide is preferred among peroxides, 1,8-diacylbis(5,4,0)-undecene (DBU) is preferred among tertiary amines, 2-ethyl-4-methylimidazolium is preferred among imidazole compounds, and 4-dimethylaminopyridine is preferred among pyridine compounds.

The aforementioned flame retardants, for example, include inorganic phosphorus compounds such as ammonium phosphate (e.g., red phosphorus, monoammonium phosphate, diammonium phosphate, triammonium phosphate, ammonium polyphosphate), and amide phosphate; phosphate esters, phosphonic acid compounds, phosphine compounds, phosphine oxide compounds, phosphorane compounds, organic nitrogen-containing phosphorus compounds, 9,10-dihydro-9-oxo-10-phosphenanthroline-10-oxide, 10-(2,5-dihydroxyphenyl)-10H-9-oxo-10-phosphenanthroline-10-oxide, and 10... -(2,7-dihydroxynaphthyl)-10H-9-oxo-10-phosphenanthrene-10-oxide and other cyclic organophosphorus compounds, and their derivatives reacting with epoxy resins or phenolic resins; nitrogen-based flame retardants such as trichloroethylene compounds, cyanuric acid compounds, isocyanuric acid compounds, and phenthiamethoxam; polysiloxane-based flame retardants such as polysiloxane oils, polysiloxane rubbers, and polysiloxane resins; and inorganic flame retardants such as metal hydroxides, metal oxides, metal carbonate compounds, metal powders, boron compounds, and low-melting-point glasses. When using these flame retardants, the resin solids content relative to the curing component is preferably in the range of 0.1% to 20% by mass.

The aforementioned inorganic filler materials are incorporated, for example, when the hardening composition of the present invention is used in semiconductor packaging materials. Examples of the aforementioned inorganic filler materials include fused silica, crystalline silica, alumina, silicon nitride, and aluminum hydroxide. Among these, fused silica is preferred in terms of the amount of inorganic filler materials that can be incorporated. The fused silica can be either crushed or spherical; however, to increase the amount of fused silica incorporated and to suppress the increase in the melt viscosity of the hardening composition, it is preferable to primarily use spherical silica. Furthermore, to increase the amount of spherical silica incorporated, it is preferable to appropriately adjust the particle size distribution of the spherical silica. The filling ratio is preferably 0.5 to 95 parts by weight in 100 parts by weight of the hardening component.

When using the hardening composition of this invention for applications such as conductive paste, conductive fillers such as silver powder or copper powder can be used.

The curable composition of this invention has excellent workability due to its low melting point or softening point. At the same time, the cured material has high heat resistance, making it particularly suitable for use in semiconductor packaging materials. In addition, it can also be widely used in electronic materials such as printed wiring boards or anti-corrosion materials, coatings or adhesives, and molded products.

When using the curable composition of this invention as a semiconductor packaging material, it is generally preferable to incorporate inorganic filler materials. The semiconductor packaging material can be prepared by mixing the admixtures, for example, using an extruder, kneader, roller, etc. Methods for packaging semiconductors using the obtained semiconductor packaging material include, for example, molding the semiconductor packaging material using a mold, transfer molding machine, injection molding machine, etc., and further heating it at a temperature of 50–250°C for 1–10 hours; by such methods, a molded semiconductor device can be obtained.

When using the curable composition of this invention for printed circuit board applications or for adding bonding films, it is generally preferable to use it mixed with an organic solvent and diluted. Examples of such organic solvents include methyl ethyl ketone, acetone, dimethylformamide, methyl isobutyl ketone, methoxypropanol, cyclohexanone, methyl cellulose, diethylene glycol ethyl ether acetate, and propylene glycol monomethyl ether acetate. The type or amount of organic solvent can be adjusted appropriately according to the application environment of the curable composition. However, for example, in printed circuit board applications, polar solvents with a boiling point below 160°C, such as methyl ethyl ketone, acetone, and dimethylformamide, are preferred, and it is preferable to use them at a non-volatile content of 40-80% by mass. In applications involving thickened adhesive films, ketone solvents such as acetone, methyl ethyl ketone, and cyclohexanone are preferred; acetate solvents such as ethyl acetate, butyl acetate, cellulose acetate, propylene glycol monomethyl ether acetate, and carbitol acetate; carbitol solvents such as cellulose and butyl carbitol; aromatic hydrocarbon solvents such as toluene and xylene; and dimethylformamide, dimethylacetamide, and N-methylpyrrolidone, preferably in a proportion of 30-60% by mass of nonvolatile components.

A method for manufacturing a printed wiring board using the curable composition of this invention includes, for example, impregnating a reinforcing substrate with the curable composition, curing it to obtain a prepreg, and then overlapping it with copper foil and heat-pressing it. The aforementioned reinforcing substrate may include paper, glass cloth, glass nonwoven fabric, polyaramid paper, polyaramid cloth, glass mat, glass yarn bundle, etc. The impregnation amount of the curable composition is not particularly limited; generally, it is preferred to prepare the prepreg so that the resin content is 20-60% by mass. [Example]

The present invention will then be illustrated in detail by way of embodiments and comparative examples. In the following, unless otherwise expressly defined, "parts" and "%" are quality standards. In the embodiments of the present invention, the determination conditions for gel osmosis chromatography (GPC), high-performance liquid chromatography (HPLC), liquid chromatography-mass analysis (LC-MS), and amine equivalent are as described below.

<Gel Osmosis Chromatography (GPC) Determination Conditions> Apparatus: Tosoh Corporation "HLC-8320 GPC" Column: Tosoh Corporation "HXL-L" Protective Column +Tosoh Corporation "TSK-GEL G2000HXL" +Tosoh Corporation "TSK-GEL G2000HXL" +Tosoh Corporation "TSK-GEL G3000HXL" +Tosoh Corporation "TSK-GEL G4000HXL" Detector: RI (Differential Refractometer) Data Processing: Tosoh Corporation "GPC Workstation EcoSEC-workStation" Determination Conditions: Column Temperature: 40℃ Development Solvent: Tetrahydrofuran Flow Rate: 1.0 ml/min Standard: Following the aforementioned "GPC Workstation EcoSEC-workStation" measurement operation manual, use monodisperse polystyrene with a known molecular weight. (Using polystyrene) Tosoh Corporation "A-500" Tosoh Corporation "A-1000" Tosoh Corporation "A-2500" Tosoh Corporation "A-5000" Tosoh Corporation "F-1" Tosoh Corporation "F-2" Tosoh Corporation "F-4" Tosoh Corporation "F-10" Tosoh Corporation "F-20" Tosoh Corporation "F-40" Tosoh Corporation "F-80" Tosoh Corporation "F-128" Sample: A tetrahydrofuran solution (50 μl) filtered using a microfilter, with a resin solids content calculated as 1.0% by mass.

<Determination Conditions for High-Speed Liquid Chromatography (HPLC) and Liquid Chromatography-Mass Analysis (LC-MS)> Controller: Agilent Technologies 1260 Infinity II Column: Agilent EC-C18 (4.6 × 50 mm, 2.7 μm) Column Temperature: 40℃ Pump Flow Rate: 1.0 ml/min Dissolution Conditions: K1-Water, K2-Acetonitrile K1/K2 = 0/100 → 30/70 (linear concentration change 0-1.67 min) K1/K2 = 30/70 (1.67-5 min) K1/K2 = 30/70 → 90/10 (5-8 min) (Ratio is volume ratio) Detection Wavelengths: UV 254, 275, 300 nm MS: Agilent Technologies InfinityLab LC/MSD

<Determination of Amine Equivalent> In a 500 mL Erlenmeyer flask with a stopper, add approximately 2.5 g of the polyaniline compound (as the sample). Accurately weigh 7.5 g of pyridine, 2.5 g of acetic anhydride, and 7.5 g of triphenylphosphine. Attach a condenser and heat under reflux in an oil bath at 120 °C for 150 minutes. After cooling the mixture, add 5.0 mL of distilled water, 100 mL of propylene glycol monomethyl ether, 75 mL of tetrahydrofuran, and approximately 50 mL of 0.5 mol/L potassium hydroxide-ethanol solution. Titrate by potentiometric titration. Perform a blank test using the same method for calibration. Amine equivalent (g/eq.) = (S × 2,000) / (Blank - A) S: Sample volume (g) A: Volume of 0.5 mol/L potassium hydroxide-ethanol solution consumed (mL) Blank: Volume of 0.5 mol/L potassium hydroxide-ethanol solution consumed in the blank test (mL)

(Example 1: Synthesis of maleimide resin (1)) In a 500 mL pear-shaped flask fitted with a rotary evaporator, 52.40 g (0.43 mol) of 2,6-dimethylamine, 64.52 g (0.43 mol) of 2,6-diethylaniline, 22.14 g of distilled water, and 22.73 g of p-toluenesulfonic acid were added, and the mixture was stirred and heated to 70°C. After maintaining the temperature at 70°C for 30 minutes, 34.98 g (0.43 mol) of 37% formalin solution was added in four portions over one hour, and the reaction was allowed to proceed for four hours. After the reaction, the mixture was cooled to room temperature, and the reaction solution was transferred to a 2 L separable flask and diluted with 140 g of toluene. The diluted solution was washed once with 100g of a 10% sodium hydroxide aqueous solution, and then washed four times with 100g of distilled water. The solution was then concentrated under reduced pressure to obtain 109.48g of polyaniline compound (1). The amine equivalent of polyaniline compound (1) was 146 eq/g.

In a 2L flask equipped with a thermometer, condenser, Dean-Stark trap, and stirrer, 78.35g (equivalent to 0.54mol in amine equivalent) of polyaniline compound (1), 231.5g of toluene, and 23.3g of dimethylformamide were added and stirred at room temperature. 59.53g (0.61mol) of maleic anhydride was added in four portions over one hour, and the reaction was further carried out at room temperature for one hour. 2.3g of p-toluenesulfonic acid monohydrate was added, the reaction mixture was heated, and the azeotropic water and toluene under reflux were cooled and separated, with only the toluene returned to the system for a 6-hour dehydration reaction. The solution cooled to 60°C was washed twice with 100g of 5% sodium bicarbonate aqueous solution and seven times with 150g of distilled water. During the process, 200g of toluene was added to improve the separation ability. The solution was concentrated under reduced pressure to obtain 105.7g of maleimide resin (1). The peaks at M+=432, 460, and 488 were confirmed by LC-MS spectroscopy. Each peak corresponds to the ammonium adduct of the following compound. Furthermore, the content of the dinuclear component (bismaleimide compound) calculated from the area ratio of the GPC chart was 96%. The GPC chart of maleimide resin (1) is shown in Figure 1.

(Example 2: Synthesis of maleimide resin (2)) In a 500mL pear-shaped flask fitted with a rotary evaporator, 52.11g (0.43mol) of 2-ethylaniline, 64.17g (0.43mol) of 2,6-diethylaniline, 22.14g of distilled water, and 22.73g of p-toluenesulfonic acid were added, and the mixture was stirred and heated to 70°C. After maintaining the temperature at 70°C for 30 minutes, 34.98g (0.43mol) of 37% formalin solution was added in four portions over one hour, allowing the reaction to proceed for four hours. After the reaction, the mixture was cooled to room temperature, and the reaction solution was transferred to a 2L separable flask and diluted with 140g of toluene. The diluted solution was washed once with 100g of a 10% sodium hydroxide aqueous solution, and then washed four times with 100g of distilled water. The solution was then concentrated under reduced pressure to obtain 119.02g of polyaniline compound (2). The amine equivalent of polyaniline compound (2) was 165 eq/g.

In a 2L flask equipped with a thermometer, condenser, Dean Stark separator, and stirrer, 87.45g (equivalent to 0.53mol in amine equivalent) of polyaniline compound (2), 231.5g of toluene, and 23.3g of dimethylformamide were added and stirred at room temperature. 59.53g (0.61mol) of maleic anhydride was added in four portions over one hour, and the reaction was further carried out at room temperature for one hour. 2.3g of p-toluenesulfonic acid monohydrate was added, the reaction mixture was heated, and the azeotropic water and toluene under reflux were cooled and separated, with only the toluene returned to the system for a 6-hour dehydration reaction. The solution cooled to 60°C was washed twice with 100g of 5% sodium bicarbonate aqueous solution and seven times with 150g of distilled water. To improve separation efficiency, 200g of toluene was added during the process. The solution was concentrated under reduced pressure to obtain 123.36g of maleimide resin (2). LC-MS spectra confirmed the peaks at M+=432, 460, and 488. Each peak corresponds to an amino adduct of the following compound. Furthermore, the content of the dinuclear component (bismaleimide compound) calculated from the area ratio in the GPC chart was 56%. The GPC chart of maleimide resin (2) is shown in Figure 2.

(Example 3: Synthesis of maleimide resin (3)) In a 500 mL pear-shaped flask fitted with a rotary evaporator, 52.11 g (0.43 mol) of 2-ethylaniline, 52.11 g (0.43 mol) of 2,6-dimethylaniline, 22.14 g of distilled water, and 22.73 g of p-toluenesulfonic acid were added, and the mixture was stirred and heated to 70°C. After maintaining the temperature at 70°C for 30 minutes, 34.98 g (0.43 mol) of 37% formalin solution was added in four portions over one hour, and the reaction was allowed to proceed for four hours. After the reaction, the mixture was cooled to room temperature, and the reaction solution was transferred to a 2 L separable flask and diluted with 140 g of toluene. The diluted solution was washed once with 100 g of a 10% sodium hydroxide aqueous solution, and then washed four times with 100 g of distilled water. The solution was then concentrated under reduced pressure to obtain 106.11 g of polyaniline compound (4). The amine equivalent was 147 eq/g.

In a 2L flask equipped with a thermometer, condenser, Dean Stark separator, and stirrer, 77.91g (equivalent to 0.53mol in amine equivalent) of polyaniline compound (3), 231.5g of toluene, and 23.3g of DMF were added and stirred at room temperature. 59.53g (0.61mol) of maleic anhydride was added in four portions over one hour, and the reaction was further carried out at room temperature for one hour. 2.3g of p-toluenesulfonic acid monohydrate was added, the reaction solution was heated, and the azeotropic water and toluene under reflux were cooled and separated, with only the toluene returned to the system for a 6-hour dehydration reaction. The solution, cooled to 60°C, was washed twice with 100g of 5% sodium bicarbonate aqueous solution and seven times with 150g of distilled water. To improve separation efficiency, 200g of toluene was added during the process. The solution was concentrated under reduced pressure to obtain 113.09g of maleimide resin (3). The peak at M+=432 was confirmed by LC-MS spectroscopy. This peak corresponds to the amino adduct of the following compound. Furthermore, the content of the dinuclear component (bismaleimide compound) calculated from the area ratio in the GPC chart was 58%. The GPC chart of maleimide resin (3) is shown in Figure 3.

(Examples 4-6: Synthesis of Maleimide Resins (4)-(6)) Maleimide resins (4)-(6) were synthesized in the same order as in Example 1, except that the types and molar numbers of the aniline compounds were changed as shown in Table 1 below. GPC charts of maleimide resins (4)-(6) are shown in Figures 4-6. The content of the diatomic components (bismaleimide compounds) of each maleimide resin, calculated from the area ratio of the GPC charts, is shown in Table 1. Furthermore, the presence of asymmetric bismaleimide compounds was confirmed from the MS spectra of each maleimide resin.

[Table 1] Aniline compound (A) 2. Nuclear components content Example 4: Maleimide resin (4) 0.43 mol of 2,6-dimethylaniline 0.43 mol of 2-methyl-6-ethylaniline 97% Example 5: Maleimide resin (5) 0.215 mol of 2,6-dimethylaniline 0.645 mol of 2,6-diethylaniline 96% Example 6: Maleimide resin (6) 0.645 mol of 2,6-dimethylaniline 0.215 mol of 2,6-diethylaniline 97%

(Examples 7-12: Evaluation of Maleimide Resins (1)-(6)) The melting point, softening point, Td5 of the cured resin, and thermal expansion rate of the cured resin were measured and evaluated using the following methods. The evaluation results are shown in Table 2.

<Determination of Melting Point> Regarding the maleimide resins obtained in Examples 1-6, differential scanning calorimetry (DSC) was used. The melting point was determined by taking the peak of the melting peak of the DSC curve measured under the following conditions. The differential scanning calorimetry (DSC) graphs of maleimide resins (1)-(6) are shown in Figures 7-12. Measuring apparatus: "DSC1" manufactured by Mettler Toledo Co., Ltd. Sample amount: Approximately 5 mg Temperature conditions: 10℃/min

<Determination of Softening Point> The softening points of the maleimide resins obtained in Examples 1-6 were determined according to JIS K7234 (circular method).

<Determination of Td5 of the Cured Products> The maleimide resins obtained in Examples 1-6 were poured into 11cm × 5cm (approximately 1mm thick) molds and cured at 200°C for 2 hours, followed by a further curing at 250°C for 2 hours to obtain the cured products. The Td5 of the cured products was determined using a TGA/DSC manufactured by Mettler Toledo Inc. Measuring Instrument: Mettler Toledo Inc. TGA/DSC 1 Measurement Range: 40°C～150°C～600°C Heating Rate: 20°C/min (40°C→150°C) Holding Time: 15 minutes (150°C) 5°C/min (150°C→600°C) Ambient Gas: Nitrogen

Determination of Thermal Expansion Rate of the Hardened Material The hardened material was obtained under the same conditions as before, and the thermal expansion rate was measured using a TMA/SS6100 instrument manufactured by Hitachi High Technology Science Co., Ltd. Measuring Instrument: TMA/SS6100 (Hitachi High Technology Science Co., Ltd.) Probe: Quartz expansion/compression probe Measurement Load: 88.8 mN Measurement Temperature: 1st run r.t. ~ 270℃ 2nd run 0 ~ 270℃ Heating Rate: 3℃/min Ambient Gas: Nitrogen

(Comparative Example 1) For comparison, 4,4'-diphenylmethane bismaleimide (manufactured by Daiwa Chemical Co., Ltd., "BMI-1000") was used, and the melting point of the maleimide resin was determined using the same method as in the embodiment. The melting point was 160°C. Furthermore, since the bismaleimide compound did not melt at 150°C, the softening point according to JIS K7234 (global method) was not determined.

[Table 2] Melting point [°C] Softening point [°C] Td5[℃] Thermal expansion rate (TMA, ppm) 40～60℃ 230～250℃ Maleimide resin (1) 67 92 509 59 92 Maleimide resin (2) 57 83 427 70 101 Maleimide resin (3) 78 117 437 52 82 Maleimide resin (4) 73 102 511 55 70 Maleimide resin (5) 64,152 84 499 66 77 Maleimide resin (6) 82 100 511 54 70

without.

Figure 1 is a GPC chart of maleimide resin (1) obtained in Example 1. Figure 2 is a GPC chart of maleimide resin (2) obtained in Example 2. Figure 3 is a GPC chart of maleimide resin (3) obtained in Example 3. Figure 4 is a GPC chart of maleimide resin (4) obtained in Example 4. Figure 5 is a GPC chart of maleimide resin (5) obtained in Example 5. Figure 6 is a GPC chart of maleimide resin (6) obtained in Example 6. Figure 7 is a differential scanning calorimetry (DSC) chart of maleimide resin (1) obtained in Example 1. Figure 8 is a differential scanning calorimetry (DSC) chart of the maleimide resin (2) obtained in Example 2. Figure 9 is a differential scanning calorimetry (DSC) chart of the maleimide resin (3) obtained in Example 3. Figure 10 is a differential scanning calorimetry (DSC) chart of the maleimide resin (4) obtained in Example 4. Figure 11 is a differential scanning calorimetry (DSC) chart of the maleimide resin (5) obtained in Example 5. Figure 12 is a differential scanning calorimetry (DSC) chart of the maleimide resin (6) obtained in Example 6.

without.

Claims (12)

A maleimide resin, characterized in that it is a maleimide of a polyamine compound (C), which is a product of the reaction of a plurality of aromatic monoamine compounds (A) with a binding agent (B), wherein at least one of the aromatic monoamine compounds (A) is a compound having an aliphatic hydrocarbon group having 1 to 4 carbon atoms at the 2,6-position of aniline. The maleimide resin of claim 1, wherein the binder (B) is any one or more of the following: aldehyde compound (B-1), ketone compound (B-2), aromatic compound represented by the following general formula (B-3), aromatic compound represented by the following general formula (B-4), aromatic compound represented by the following general formula (B-5), aromatic compound represented by the following general formula (B-6), aromatic compound represented by the following general formula (B-7), and aromatic compound represented by the following general formula (B-8). [In general formulas (B-3) to (B-8), Ar ¹ is independent and represents an aromatic ring that may have substituents; R ¹ is independent and is a hydrogen atom or a methyl group; R ² is independent and is a hydrogen atom or an aliphatic hydrocarbon with 1 to 4 carbon atoms; R ³ is independent and is any one of an aliphatic hydrocarbon, alkoxy, alkenoxy, alkynoxy, halogen atom, aryl, or aralkyl group, and l is an integer from 0 to 3; X is any one of a hydroxyl group, halogen atom, or alkoxy group; Y is a single bond, any one of a divalent aliphatic hydrocarbon with 1 to 6 carbon atoms, an oxygen atom, a sulfur atom, or a sulfonylurate group]. The maleimide resin of claim 1 or 2 contains a maleimide compound of an asymmetric diamine compound (C-1), wherein the asymmetric diamine compound (C-1) is formed by the bonding of two different aromatic monoamine compounds (A) via a binder (B). An asymmetric bismaleimine compound is a maleimide of an asymmetric diamine compound (C-1) formed by the bonding of two different aromatic monoamine compounds (A) via a binder (B), wherein at least one of the aromatic monoamine compounds (A) is a compound having an aliphatic hydrocarbon group having 1 to 4 carbon atoms at the 2,6-position of aniline. The asymmetric bismaleimine compound in claim 4 is represented by the following general formula (4): [In the formula, Z is a divalent organic group with 1 to 200 carbon atoms; ^R4 is independent and is any one of aliphatic hydrocarbon, alkoxy, alkenoxy, alkynoxy, halogen, aryl, or aralkyl; when ^R4 exists in a complex number, they may be the same or different; m is an integer from 0 to 4; the structural sites α and β enclosed by the dashed lines in the formula have different structures.] A curable composition comprising a maleimide resin as described in any of claims 1 to 3, or an asymmetric bismaleimide compound as described in claims 4 or 5. A hardened form of a hardening composition as described in claim 6. A semiconductor packaging material that uses the curable composition as described in claim 6. A semiconductor device that uses the semiconductor packaging material as described in claim 8. A prepreg, which uses a hardening composition as described in claim 6. A circuit board that uses the prepreg as described in claim 10. A laminated film, which uses a curable composition as described in claim 6.