Heat-curable maleimide resin composition, and bonding film, build-up film, resin-coated copper foil, prepreg, and laminate, and printed wiring board using them

Abstract

Provides a thermosetting resin composition that imparts a cured product with low dielectric constant, low dielectric loss tangent, and excellent adhesion. A thermosetting maleimide resin composition comprising (A) a maleimide resin that is solid at 25°C, (B) an epoxy resin containing two or more epoxy groups in one molecule, (C) an anionic polymerization initiator, and (D) a hollow inorganic filler.

Description

Technology Field

[0001] The present invention relates to a thermosetting maleimide resin composition. Background Technology

[0002] In recent years, next-generation communication systems known as 5G (in the millimeter wave range of 26 GHz to 80 GHz) have become popular, and furthermore, the development of the next-next-generation communication system known as 6G has begun. To realize communication systems capable of higher speeds, larger capacity, and lower latency than current ones, materials suitable for high frequencies of 3 to 80 GHz are required, and reducing transmission loss is essential as a noise countermeasure. This transmission loss is the sum of conductor loss and dielectric loss, and reducing conductor loss requires the surface of the metal foil used, particularly copper foil. Meanwhile, since dielectric loss is proportional to the product of the square root of the relative permittivity and the dielectric loss tangent, the development of insulating materials with excellent dielectric properties (low relative permittivity and low dielectric loss tangent) is required. Among these, insulating materials with particularly excellent dielectric properties are required for substrate applications. For rigid substrates, a material called reactive polyphenylene ether resin (PPE) has been used. In addition, materials called liquid crystal polymers (LCP) or modified polyimide (MPI) have been used in flexible printed circuit boards (FPC).

[0003] In this regard, it has been reported that maleimide compounds having a dimerdiamine backbone (special maleimide compounds) are used as the main resin for substrates (Patent Documents 1 and 2). Unlike the characteristics of general maleimide resins, special maleimide compounds have characteristics such as a low glass transition temperature (Tg) and a high coefficient of thermal expansion (CTE). Furthermore, compared to conventional thermosetting resins, they have excellent dielectric properties and also possess flexible properties. In addition, they have many advantages, such as superior adhesion to metals and the like compared to epoxy resins, and the possibility of (high)multilayering because they are thermosetting resins, so they are being researched and developed over a wide range of areas.

[0004] Meanwhile, regarding the dimensional stability of the substrate, it has been reported that other aromatic maleimide compounds having high Tg are used in combination with special maleimide compounds (Patent Documents 3 to 5). However, aromatic maleimide compounds have problems such as a tendency for dielectric properties to deteriorate in the millimeter wave region above 28 GHz, as well as being prone to moisture absorption, lack of compatibility, easy separation of the cured product, and easy variation in quality. In contrast, it was found that a method to increase the Tg of the special maleimide compound itself can be realized by using a maleimide compound combined with a diamine other than dimerdiamine (Patent Document 6). Furthermore, it was found that a well-balanced composition could be obtained by combining multiple types of special maleimide compounds (Patent Documents 7 and 8).

[0005] In practice, it is common practice to lower the CTE or dielectric loss tangent by adding inorganic fillers such as silica to these compositions; however, since inorganic fillers such as silica are oxides, they have high dielectric constants. Consequently, when a silica-containing composition is formed, the dielectric constant value increases, reaching a stage that is unsatisfactory for future high-speed communication applications.

[0006] To address these issues, it has been proposed to use hollow inorganic fillers (Patent Documents 9 to 12). However, these are difficult to describe as compositions with overall balance because the dielectric properties of the resin used are insufficient. Prior art literature

[0007] International Publication No. 2016 / 114287, Japanese Patent Publication No. 2018-201024, International Publication No. 2016 / 114286, Japanese Patent Publication No. 2018-12764, Japanese Patent Publication No. 2018-12772, Japanese Patent Publication No. 2019-203122, Japanese Patent Publication No. 2023-67339, Japanese Patent Publication No. 2023-67340, Japanese Patent Publication No. 2020-83966, Japanese Patent Publication No. 2024-59029, Japanese Patent Publication No. 2013-173841, Japanese Patent Publication No. 2024-92800 The problem to be solved

[0008] Accordingly, the present invention aims to provide a thermosetting resin composition that imparts a cured product having low dielectric constant, low dielectric loss tangent, and excellent adhesion, and also to provide a bonding film, prepreg, copper foil, build-up film, and printed circuit board containing said composition. means of solving the problem

[0009] As a result of repeated diligent research to solve the above problem, the inventors discovered that the following thermosetting resin composition can achieve the above objective and completed the present invention.

[0010] [1]

[0011] (A) Maleimide resin represented by the following formula (1) and solid at 25°C,

[0012]

[0013] (In Formula (1), A is independently a tetravalent organic group having a cyclic structure, B is independently a divalent hydrocarbon group having 6 to 60 carbon atoms, D is independently a divalent alicyclic hydrocarbon group having 6 to 200 carbon atoms, or a hydrocarbon group derived from one or more selected from the dimerdiamine backbone and the trimertriamine backbone, and one or more of D are hydrocarbon groups derived from one or more selected from the dimerdiamine backbone and the trimertriamine backbone. m is 0 to 100, and n is 0 to 100. The order of each repeating unit grouped by m and n is not limited, and the bonding mode may be alternating, block, or random.)

[0014] (B) An epoxy resin containing two or more epoxy groups in one molecule,

[0015] (C) Anionic polymerization initiator and

[0016] (D) Chinese weapon filler

[0017] A thermosetting maleimide resin composition comprising

[0018] [2]

[0019] A thermosetting maleimide resin composition described in [1], wherein A in the above formula (1) is any of the tetravalent organic groups represented by the following formula.

[0020]

[0021] (A bonding hand in the above structural formula that is not bonded to a substituent is bonded to the carbonyl carbon forming the cyclic imide structure in the above formula (1).)

[0022] [3]

[0023] The above (C) anionic polymerization initiator is a thermosetting maleimide resin composition described in [1] or [2], which is an imidazole compound having a triazine ring.

[0024] [4]

[0025] A thermosetting maleimide resin composition in which the hollow inorganic filler of component (D) is one or more selected from hollow silica and hollow glass [1] to [3].

[0026] [5]

[0027] The thermosetting maleimide resin composition described in [4], wherein the hollow inorganic filler of component (D) above is treated with a silane coupling agent.

[0028] [6]

[0029] A thermosetting maleimide resin composition described in any one of [1] to [5] containing, additionally, a solid inorganic filler as a component (E).

[0030] [7]

[0031] (E) A thermosetting maleimide resin composition described in [6], in which the solid inorganic filler of the component is spherical silica with an average particle size of 0.1 to 5.0 μm.

[0032] [8]

[0033] A bonding film comprising a thermosetting maleimide resin composition as described in any one of [1] to [7].

[0034] [9]

[0035] A build-up film comprising a thermosetting maleimide resin composition as described in any one of [1] to [7].

[0036]

[10]

[0037] A resin-attached copper foil comprising a thermosetting maleimide resin composition as described in any one of [1] to [7].

[0038]

[11]

[0039] A prepreg comprising a thermosetting maleimide resin composition as described in any one of [1] to [7].

[0040]

[12]

[0041] A laminate comprising a thermosetting maleimide resin composition as described in any one of [1] to [7].

[0042]

[13]

[0043] Printed circuit board using the material described in any of [8] to

[12] . Effects of the invention

[0044] The curable resin composition of the present invention provides a cured product having a low relative dielectric constant, a low dielectric loss tangent, and excellent adhesion. Accordingly, the thermosetting maleimide resin composition of the present invention is useful for bonding films, build-up films, resin-attached copper foils, prepregs, laminates, and further printed circuit boards. Specific details for implementing the invention

[0045] The present invention will be described in more detail below.

[0046] [(A) Maleimide resin that is solid at 25℃]

[0047] The component (A) of the present invention is a maleimide resin that is solid at 25°C, represented by the following formula (1).

[0048]

[0049] (In Formula (1), A is independently a tetravalent organic group having a cyclic structure, B is independently a divalent hydrocarbon group having 6 to 60 carbon atoms, D is independently a divalent alicyclic hydrocarbon group having 6 to 200 carbon atoms or a hydrocarbon group derived from one or more selected from a dimerdiamine backbone and a trimertriamine backbone, and one or more of D are hydrocarbon groups derived from one or more selected from a dimerdiamine backbone and a trimertriamine backbone. m is 0 to 100, and n is 0 to 100. The order of each repeating unit grouped by m and n is not limited, and the bonding mode may be alternating, block, or random.)

[0050] The component (A) of the present invention is characterized by having one or more hydrocarbon groups derived from one or more selected from a dimerdiamine backbone and a trimertriamine backbone in one molecule. By having hydrocarbon groups derived from a dimerdiamine backbone and a trimertriamine backbone, the cured product of the composition containing the component (A) exhibits a low elastic modulus as the crosslinking density is reduced, and the adhesion is improved as the wettability to the substrate, in this case glass, is improved. In addition, this part is also effective for improving dielectric properties (low dielectric constant, low dielectric loss tangent).

[0051] The term "dimerdiamine" as used herein refers to a liquid dibasic acid in which a carboxylic acid is aminomethylated, with the carboxylic acid being the main component, which is produced by the dimerization of an unsaturated fatty acid having 18 carbon atoms, which is a raw material such as a plant oil or other natural product called a dimer acid. Dimer acids do not have a single backbone but possess multiple structures and exist as multiple isomers. Representative dimer acids are classified by the names straight-chain (a), monocyclic (b), aromatic (c), and polycyclic (d). In this specification, a dimer acid backbone refers to a group derived from a dimerdiamine having a structure in which the carboxyl groups of such dimer acids are substituted with primary aminomethyl groups. That is, component (A) is a dimer acid backbone, and in each dimer acid represented by (a) to (d) below, it is preferable that it has a group in which two carboxyl groups are substituted with methylene groups.

[0052]

[0053] In addition, regarding the heat resistance and reliability of the cured product, it is more desirable that the hydrocarbon groups derived from the dimerdiamine backbone of the maleimide resin of component (A) have a structure in which the carbon-carbon double bonds among the hydrocarbon groups derived from the dimerdiamine backbone are reduced by a hydrogenation reaction.

[0054] Furthermore, the trimertriamine referred to here is an aminomethylated carboxylic acid among the by-products generated during the synthesis of dimer acids, which are essentially called trimer acids. Trimer acids are tribasic acids composed mainly of C54 tricarboxylic acids, produced by the trimerization of C18 unsaturated fatty acids derived from natural materials such as plant oils. Like dimer acids, trimer acids do not have a single backbone but possess multiple structures, and multiple isomers exist.

[0055] In addition, regarding the heat resistance and reliability of the cured product, it is more desirable that the hydrocarbon groups derived from the trimertriamine backbone in the maleimide resin of component (A) have a structure in which the carbon-carbon double bonds among the hydrocarbon groups derived from the trimertriamine backbone are reduced by a hydrogenation reaction.

[0056] In addition, in the above formula (1), A represents a tetravalent organic group having an independent cyclic structure, and among them, it is preferable that it be any of the tetravalent organic groups represented by the following formula.

[0057]

[0058] (A bonding hand in the above structural formula that is not bonded to a substituent is bonded to the carbonyl carbon forming the cyclic imide structure in the above formula (1).)

[0059] In addition, in the above formula (1), D is independently a divalent alicyclic hydrocarbon group having 6 to 200 carbon atoms or a hydrocarbon group derived from one or more selected from a dimerdiamine backbone and a trimertriamine backbone, and one or more of D are hydrocarbon groups derived from one or more selected from a dimerdiamine backbone and a trimertriamine backbone. In addition, as the divalent alicyclic hydrocarbon group, a divalent alicyclic hydrocarbon group having 6 to 200 carbon atoms, preferably 8 to 80 carbon atoms, is preferred. Among these, a branched divalent alicyclic hydrocarbon group in which one or more hydrogen atoms of the divalent alicyclic hydrocarbon group are substituted with an alkyl group or an alkenyl group having 6 to 60 carbon atoms, preferably 8 to 60, more preferably 10 to 55 carbon atoms, is more preferred. As for the branched divalent alicyclic hydrocarbon group, it may be either a saturated aliphatic hydrocarbon group or an unsaturated hydrocarbon group, and may have an alicyclic structure or an aromatic ring structure in the middle of the molecular chain.

[0060] In addition, in the above formula (1), B is independently a divalent hydrocarbon group having 6 to 60 carbon atoms. In particular, it is independently a divalent aliphatic hydrocarbon group having 6 to 60 carbon atoms or an aromatic hydrocarbon group having 6 to 60 carbon atoms. Preferably, it is a divalent aliphatic hydrocarbon group having 6 to 30 carbon atoms or an aromatic hydrocarbon group. The divalent hydrocarbon group may include a cyclic structure or a branched structure, but the group represented by D is not included. In addition, the divalent aromatic hydrocarbon group may have bonding losses directly in the aromatic ring, or may have bonding losses interposed between a straight-chain or branched divalent aliphatic hydrocarbon group from the aromatic ring.

[0061] In the above equation (1), division is performed in the case of m and n.

[0062] [Condition 1: When m=1 to 100, n=1 to 100]

[0063] First, in the case where m=1 to 100 and n=1 to 100, the maleimide resin has a high melt viscosity before curing, but its dielectric properties are superior to those of a maleimide resin containing a large number of aromatic rings. Furthermore, it has high adhesion to copper foil and has a lower moisture absorption than general thermosetting resins such as epoxy resin, so the influence of moisture is small. In addition, the maleimide resin with m=1 to 100 also has a higher Tg than the maleimide resin with n=0, and has a smaller coefficient of thermal expansion (CTE), resulting in a highly reliable composition.

[0064] When m=1 to 100 and n=1 to 100, the number of m is preferably 1 to 60, and more preferably 2 to 50. The number of n is preferably 1 to 60, more preferably 1 to 50, and even more preferably 1 to 40. In particular, it is desirable that the range of m+n is 2 to 50 from the perspective of the fluidity, moldability, and strength of the cured product of the composition. On the other hand, if m+n is greater than 50, fluidity decreases, and there is a risk that moldability may decrease.

[0065] The order of each repeating unit grouped by m and n is not limited, and the combination mode may be alternating, block, or random, but among these, a block is preferable from the perspective that it is easy to increase Tg. Also, when m and n are within this range, it is basically a solid at 25°C.

[0066] [Condition 2: When m=1 to 100, n=0]

[0067] Next, this is the case where m=1 to 100 and n=0. Maleimide resins in this range had superior dielectric properties compared to other general maleimide resins containing a large number of aromatic rings. In particular, not only is it effective in maintaining dielectric properties even under high frequency or high temperature and high humidity conditions, but it also has stronger adhesion to copper foil or other resins than maleimide resins satisfying condition 1, resulting in an excellent composition.

[0068] In the above formula (1), m is 1 to 100, preferably 1 to 60, and more preferably 1 to 50. If m is too large, solubility or fluidity is reduced, and there is a risk that moldability will decrease.

[0069] The number average molecular weight of the maleimide resin of component (A) satisfying either of the two conditions above is not particularly limited, but is preferably 1,000 to 50,000 and more preferably 2,000 to 30,000 for the sake of the handling properties of the composition. In addition, component (A) may be of only one type or may include multiple types.

[0070] In addition, the number average molecular weight mentioned in the present invention refers to the number average molecular weight using polystyrene as a standard material by gel permeation chromatography (GPC) measured under the following conditions.

[0071] [Measurement Conditions]

[0072] Developing solvent: Tetrahydrofuran (THF)

[0073] Flow rate: 0.35 mL / min

[0074] Detector: Parallax Refractive Index Detector (RI)

[0075] Column: TSK Guardcolumn SuperH-L

[0076] TSKgel SuperHZ4000 (4.6㎜ID×15㎝×1)

[0077] TSKgel SuperHZ3000 (4.6㎜ID×15㎝×1)

[0078] TSKgel SuperHZ2000 (4.6㎜ID×15㎝×2)

[0079] (All Dososaje)

[0080] Column temperature: 40℃

[0081] Sample injection volume: 5 μL (THF solution with a concentration of 0.2 mass%)

[0082] [Condition 3: When m=n=0]

[0083] Finally, it is a maleimide resin satisfying m=n=0, but this is the simplest structure among the above formulas (1) having maleimides at both ends and a dimerdiamine backbone in the center. It has superior dielectric properties compared to other general maleimide resins containing multiple aromatic rings. In particular, it is effective in maintaining dielectric properties even at high frequencies. In addition, since it is liquid at 25°C, it has the effect of improving the moldability of the resin composition of the present invention or improving handling properties such as film properties before curing.

[0084] Therefore, when using a maleimide resin that satisfies this condition, it is used in combination with one or more of the aforementioned maleimide resins that are solid at 25°C.

[0085] As for the viscosity of this maleimide resin, it is preferable that the value measured at 25°C and 5 rpm using a cone-plate type rotational viscometer described in JIS Z 8803:2011 is 1.0 to 5.0 Pa·s.

[0086] [(B) Epoxy resin having two or more epoxy groups in one molecule]

[0087] In the thermosetting maleimide resin composition of the present invention, an epoxy resin having two or more epoxy groups in one molecule is used as component (B). By incorporating the epoxy resin, the adhesion of the resin composition to a substrate can be increased, or other mechanical properties can be improved.

[0088] (B) As for the component, it is preferable to use an epoxy resin having glycidyl groups, considering reactivity and preservation properties.

[0089] (B) Examples of components include phenol novolak type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, biphenol type epoxy resin, naphthalene type epoxy resin, anthracene type epoxy resin, naphthol type epoxy resin, xylylene type epoxy resin, biphenyl type epoxy resin, biphenylaralkyl type epoxy resin, triphenylmethane type epoxy resin, alicyclic type epoxy resin, glycidylamine type epoxy resin, dicyclopentadiene type epoxy resin, stilbene type epoxy resin, sulfur atom-containing epoxy resin, phosphorus atom-containing epoxy resin, amino type epoxy resin, etc.

[0090] (B) If a component is used in a liquid state at 25°C, it is preferable in terms of compatibility and wettability to the substrate, and among them, a glycidylamine type epoxy resin is more preferable.

[0091] (B) As for the amount of component (B), it is preferable to mix 0.05 to 20 parts by mass with respect to 100 parts by mass of the total of component (A) and component (B), and more preferable to mix 0.1 to 15 parts by mass. Within the above range, it is desirable for the curing speed to be appropriate during molding. In addition, the balance of heat resistance, moisture resistance, and low dielectric properties of the obtained cured product is improved, and the adhesion to the substrate is also easily enhanced.

[0092] In addition, the epoxy resin of component (B) may be used as a single type or in combination with two or more types.

[0093] [(C) Anionic polymerization initiator]

[0094] Component (C) is incorporated to initiate and promote the curing reaction of the thermosetting maleimide resin of the present invention. Considering the reaction between the maleimide resin of component (A) and the epoxy resin of component (B), component (C) uses an anionic polymerization initiator. Examples of anionic polymerization initiators include basic compounds such as imidazoles and tertiary amines, or organic phosphorus compounds, and imidazoles are preferably used.

[0095] In addition, as an anionic polymerization initiator for component (C), an imidazole compound having a triazine ring is more preferable. The triazine ring is not only effective for improving adhesion, but also has suitable curability and storage stability.

[0096] Specifically, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine (trade name 2MZ-A, manufactured by Shikoku Kasei Holdings Co., Ltd.), 2,4-diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-triazine (trade name C11Z-A, manufactured by Shikoku Kasei Holdings Co., Ltd.), 2,4-diamino-6-[2'-ethyl-4'methylimidazolyl-(1')]-ethyl-s-triazine (trade name 2E4MZ-A, manufactured by Shikoku Kasei Holdings Co., Ltd.), and 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanuric acid adduct (trade name 2MA-OK, Shikoku Kasei Examples include Holdings Co., Ltd.

[0097] The amount of component (C) is 0.1 to 5 parts by mass per 100 parts by mass of the total of components (A) and (B), and 0.5 to 3 parts by mass is more preferable. If the amount of component (C) per 100 parts by mass of components (A) and (B) is less than 0.1 parts by mass, it is not desirable because the curability is reduced, and if it exceeds 5 parts by mass, it is not desirable because the storage stability of the composition is deteriorated.

[0098] (C) The ingredient may be used as a single type or in combination with two or more types.

[0099] On the other hand, a radical polymerization initiator may be used in combination to promote the reaction of functional groups in the resin. This cures thermosetting resins that do not react with anionic polymerization initiators, or promotes the reaction between maleimide groups. Generally, the cured product has low dielectric properties when reacted solely by radical polymerization, but the epoxy groups of component (B) remain unreacted in the system, which may cause problems such as leaching. Therefore, the use of a radical polymerization initiator is not particularly desirable for this application, but it is possible to use it in combination to the extent that it does not impair curability.

[0100] [(D) Chinese weapon filler]

[0101] The thermosetting maleimide resin composition of the present invention further includes a hollow inorganic filler as component (D). Inorganic fillers that are generally used as fillers and are so-called solid rather than hollow (described later) are incorporated for the purpose of increasing the strength or stiffness of the cured product of the composition, or adjusting the coefficient of thermal expansion or the dimensional stability of the cured product, but generally have a high dielectric constant. Here, the dielectric constant can be lowered by using a hollow inorganic filler.

[0102] As for the hollow inorganic filler, there are no particular limitations, but hollow silica or hollow glass are preferred from the perspective of particle strength or ease of acquisition, and hollow silica is more preferably when dielectric properties are added. Hollow silica and hollow glass may be used individually or in combination.

[0103] The average particle size and shape of the hollow inorganic filler are not particularly limited, but spherical silica with an average particle size of 0.1 to 5 μm is particularly suitable for use from the perspective of substrate processability. Furthermore, the average particle size is the mass average value D in the particle size distribution measurement by laser light diffraction. 50 It is a value obtained as (or median diameter).

[0104] The porosity of the hollow inorganic filler is preferably 20 to 90 volume%, more preferably 30 to 80 volume%. When the porosity is within this range, the reduction of the dielectric constant and dielectric loss tangent of the cured product of the thermosetting resin composition, as well as the balance of strength and dimensional stability of the cured product, is improved. For example, if the porosity is too small, the dielectric constant does not decrease significantly, and if the porosity is too large, the strength of the particles is low, causing the particles to break, and there is a tendency not to obtain the desired effect. Here, porosity refers to the volume ratio of the space within the particles to the volume of the inorganic filler.

[0105] In addition, to improve properties or dispersibility, it is preferable that the hollow inorganic filler be surface-treated with a silane coupling agent having an organic group capable of reacting with the functional groups of components (A) to (D). Examples of such silane coupling agents include epoxy group-containing alkoxysilanes, amino group-containing alkoxysilanes, (meth)acrylic group-containing alkoxysilanes, and alkenyl group-containing alkoxysilanes.

[0106] As the above silane coupling agent, an alkoxysilane containing (meth)acrylic and / or amino groups is suitably used, and specifically, examples include 3-methacryloxypropyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, etc.

[0107] In addition, in the thermosetting resin composition of the present invention, the above component (D) is 1 to 60 mass% of the total composition, preferably 3 to 55 mass%, and more preferably 5 to 50 mass%. In addition, the component (D) may be used alone or two or more may be used in combination.

[0108] [(E) Solid Inorganic Filler]

[0109] The thermosetting resin composition of the present invention may additionally include a solid-phase inorganic filler as component (E). As previously mentioned, solid-phase inorganic fillers tend to increase the dielectric constant of the cured product of the thermosetting resin composition of the present invention, but they may be incorporated because they have a higher ability to increase strength or stiffness, or to adjust the coefficient of thermal expansion or the dimensional stability of the cured product, than hollow-phase inorganic fillers. There is a high tendency to obtain a thermosetting resin composition with a good balance of mechanical properties, etc., by using component (D) and component (E) in combination.

[0110] As for the solid inorganic filler, those typically incorporated into epoxy resin compositions or silicone resin compositions can be used; however, in order to lower the dielectric loss tangent without excessively increasing the relative dielectric constant of the entire composition, silica particles such as spherical silica, fused silica, and crystalline silica, or boron nitride are preferred.

[0111] The average particle size and shape of the solid inorganic filler are not particularly limited, as with component (E); however, spherical silica with an average particle size of 0.1 to 5 μm is particularly suitable for use from the perspective of substrate processability. Furthermore, the average particle size is the mass average value D in the particle size distribution measurement by laser light diffraction. 50 It is a value obtained as (or median diameter).

[0112] In addition, similar to component (D), it is desirable that the solid inorganic filler be surface-treated with a silane coupling agent having an organic group capable of reacting with the functional groups of component (A) or component (B) in order to improve properties. Examples of such silane coupling agents include epoxy group-containing alkoxysilanes, amino group-containing alkoxysilanes, (meth)acrylic group-containing alkoxysilanes, and alkenyl group-containing alkoxysilanes.

[0113] As the above silane coupling agent, (meth)acrylic group-containing alkoxysilanes and amino group-containing alkoxysilanes are suitably used, specifically, 3-methacryloxypropyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, etc. The above silane coupling agent may be used alone or in combination of two or more types.

[0114] In addition, when the above component (E) is incorporated into the thermosetting resin composition of the present invention, the amount is 1 to 60 mass% of the total composition, preferably 5 to 55 mass%, and more preferably 10 to 50 mass%. In addition, component (E) may be used alone or two or more may be used in combination.

[0115] [Other Additives]

[0116] Various additives may be further incorporated into the thermosetting resin composition of the present invention as needed. Other additives are exemplified below.

[0117] [Thermosetting resin having reactive groups capable of reacting with maleimide groups]

[0118] In addition to the present invention, a thermosetting resin having a reactive group capable of reacting with component (A) or component (B) may be added. The type thereof is not limited, and examples include various resins such as melamine resin, silicone resin, cyclic imide resin containing maleimide other than component (A), urea resin, thermosetting polyimide resin, modified polyphenylene ether resin, thermosetting acrylic resin, and epoxy-silicone hybrid resin.

[0119] In addition, reactive groups capable of reacting with the cyclic imide group may include the cyclic imide group, hydroxyl group, acid anhydride group, alkenyl group such as allyl or vinyl group, (meth)acryl group, thiol group, etc. However, from the perspective of reactivity, it is preferable that the reactive group be selected from the cyclic imide group, hydroxyl group, and alkenyl group, and additionally, from the perspective of dielectric properties, the alkenyl group or (meth)acryl group is more preferable.

[0120] However, the mixing amount is preferably 0 to 40 mass% of the total amount of the thermosetting resin composition of the present invention.

[0121] In addition to the above, non-functional silicone oil, reactive diluent, thermoplastic resin, thermoplastic elastomer, organic synthetic rubber, photosensitizer, light stabilizer, polymerization inhibitor, flame retardant, pigment, dye, adhesion aid, ion trapper, etc. may be incorporated.

[0122] In addition, silane coupling agents such as epoxy group-containing alkoxysilanes, amino group-containing alkoxysilanes, (meth)acrylic group-containing alkoxysilanes, and alkenyl group-containing alkoxysilanes, which surface treat the hollow inorganic fillers or solid inorganic fillers described above, may be incorporated separately into the thermosetting resin composition of the present invention. Specific examples of silane coupling agents include those similar to those described above.

[0123] The thermosetting maleimide resin composition of the present invention may be dissolved in an organic solvent and processed as a varnish or slurry. By making the composition into a varnish, it becomes easier to form a film, and it also becomes easier to coat or impregnate glass cloths made of E glass, low dielectric glass, quartz glass, etc. Regarding the organic solvent, any solvent that dissolves the thermosetting resin having reactive groups capable of reacting with component (A) or component (B) and optionally the component (A) or (B) may be used without limitation, but examples include anisole, tetralin, mesitylene, xylene, toluene, tetrahydrofuran (THF), dimethylformamide (DMF), dimethyl sulfoxide (DMSO), acetonitrile, etc., and among these, aromatic organic solvents such as anisole, tetralin, mesitylene, xylene, and toluene are preferred. Ketone-based solvents with a low boiling point of 100°C or lower, such as methyl ethyl ketone (MEK) or methyl isobutyl ketone (MIBK), are also frequently used when making varnishes and slurries, but the maleimide resin of component (A) used in the present invention has low solubility in such ketone-based solvents, so their use may not be desirable. In addition, these organic solvents may be used as a single type or in combination of two or more types.

[0124] As a method for preparing the thermosetting resin composition of the present invention, the components (A), (B), (C), and (D) and other additives added as needed can be mixed using, for example, a planetary mixer (manufactured by Inoue Seisakusho Co., Ltd.) or a stirring THINKY CONDITIONING MIXER (manufactured by Shinky Co., Ltd.). At this time, it is preferable to select a method that does not apply too high a load so that component (D) does not split.

[0125] This thermosetting resin composition can be formed into an uncured resin sheet or an uncured resin film by coating the aforementioned varnish onto a substrate and then volatilizing the organic solvent, or further cured into a cured resin sheet or a cured resin film. Methods for manufacturing sheets and films are exemplified below, but are not limited thereto.

[0126] For example, after coating a substrate with a thermosetting resin composition (varnish) dissolved in an organic solvent, the organic solvent is removed by heating at a temperature of typically 80°C or higher, preferably 100°C or higher, for 0.5 to 20 minutes, and then further heated at a temperature of 130°C or higher, preferably 150°C or higher, for 0.5 to 10 hours, thereby forming a resin cured film with a flat and solid surface. The temperatures in the drying process for removing the organic solvent and the subsequent heat curing process may each be constant, but it is preferable to increase the temperature in stages. By doing so, the organic solvent is efficiently removed from the composition, and the curing reaction of the resin proceeds efficiently. Examples of varnish coating methods include spin coaters, slit coaters, spray coaters, dip coaters, bar coaters, etc., but there are no particular limitations.

[0127] As the substrate, a general resin substrate may be used, such as polyolefin resins like polyethylene (PE) resin, polypropylene (PP) resin, and polystyrene (PS) resin, and polyester resins such as polyethylene terephthalate (PET) resin, polybutylene terephthalate (PBT) resin, and polycarbonate (PC) resin. It is acceptable for the surface of the substrate to be treated with a release agent. Additionally, the thickness of the coating layer is not particularly limited, but the thickness after solvent distillation removal is in the range of 1 to 200 μm, preferably 3 to 150 μm. It is also acceptable to use a cover film on the coating layer. Furthermore, each component may be pre-mixed and extruded into a sheet or film using a melt kneader for immediate use.

[0128] The film obtained in this way can be used as a bonding film or a build-up film. As a bonding film, it can be used between a core material and a coverlay film for manufacturing flexible printed circuit boards, or between an organic substrate and a build-up film. The build-up film is used in a method for manufacturing laminated boards or printed circuit boards called the Semi-Additive Process (SAP) or its improved method (M-SAP).

[0129] Here, a copper foil can be used as a substrate, and a resin-attached copper foil can be produced by forming an uncured or semi-cured film on the copper foil in the same manner as above. In other words, as in the above, a thermosetting resin can be dissolved in an organic solvent to form a varnish, coated onto a release-treated polyethylene terephthalate (PET) film, dried to produce a film, attached to the copper foil, and peeled off the PET film to obtain a resin-attached copper foil. At this time, although the lamination conditions are not particularly limited, it is preferable to laminate while heating at a temperature of 80 to 130°C, 0.1 to 1.0 MPa, and for 0.5 to 5 minutes.

[0130] Although there are no specific limitations on the roughness of the copper foil used, from the perspective of reducing conductor loss, it is preferable to use a copper foil with a 10-point average roughness (Rz) of the surface roughness of the uncured or semi-cured thermosetting resin in contact with the copper foil at a rate of 1.5 μm or less. For reducing conductor loss, it is desirable to have a small Rz, preferably 1.3 μm or less, and more preferably 1.0 μm or less. On the other hand, regarding adhesion, materials with a small Rz tend to have a tendency for the anchoring effect to be difficult to obtain and the adhesion strength to decrease, but since the thermosetting maleimide resin composition of the present invention has high adhesion strength, it can be used even with copper foil of such low roughness.

[0131] The manufacturing method of the copper foil used does not particularly matter, but it is generally produced by electrolysis or rolling, and electrolytic copper foil is widely used. Additionally, it is acceptable to use copper foil that has undergone surface treatment to improve adhesion, heat resistance, and chemical resistance.

[0132] The thickness of the copper foil does not particularly matter, but it is generally used in the range of 6 to 50 μm. As for thinner ones, they can be used in an embodiment called carrier-attached copper foil. This involves attaching a carrier to a thin copper foil to improve handling properties, giving it thickness, and then removing the carrier in a subsequent process.

[0133] In addition, the thermosetting resin composition of the present invention, which has been varnished, can be impregnated into a fiber substrate such as a glass cloth made of E glass, low dielectric glass, or quartz glass, and then the organic solvent is removed to make it semi-cured so that it can also be used as a prepreg. Furthermore, by laminating the prepreg or copper foil, etc., a laminated board or printed circuit board containing a high number of layers can be produced.

[0134] This prepreg comprises a thermosetting resin and a fiber substrate. The thermosetting resin is the thermosetting resin composition or a semi-cured resin composition. Furthermore, a semi-cured resin is a state in which the resin composition has been cured to an intermediate degree to allow for further curing. That is, the semi-cured resin is in a semi-cured state of the resin composition, so-called B-stage. Meanwhile, an uncured state is sometimes referred to as A-stage. That is, the thermosetting resin may be the thermosetting resin composition in the A-stage state or the thermosetting resin composition in the B-stage state. As previously mentioned, the fiber substrate may be E glass, low dielectric glass, quartz glass, and furthermore, S glass, T glass, etc. Regardless of the type of glass used, a quartz glass cross having low dielectric properties is preferred from the perspective of utilizing the characteristics of the thermosetting resin composition. In addition, the thickness of the fiber substrate generally used is, for example, 0.01 mm or more and 0.3 mm or less.

[0135] When manufacturing prepreg, it is preferable that the thermosetting resin be a varnish as described above in order to impregnate the fiber substrate, which is the substrate for forming the prepreg. As a method for manufacturing prepreg, for example, a method of impregnating the fiber substrate with a thermosetting resin composition prepared in the form of a varnish and then drying it may be used. The thermosetting resin is impregnated into the fiber substrate by immersion, coating, etc. It is also possible to repeat the impregnation process multiple times as needed. Furthermore, by repeating the impregnation process using multiple resin compositions with different compositions or concentrations, it is possible to adjust the final composition and impregnation amount to a desired level. The fiber substrate impregnated with the resin composition (resin varnish) is heated under desired heating conditions, for example, at a temperature of 80°C or higher and 180°C or lower for 1 minute or more and 20 minutes or less. By heating, a prepreg having a thermosetting resin of stage A or stage B is obtained. In addition, by heating as described above, the organic solvent can be reduced or removed by volatilizing the organic solvent from the varnish.

[0136] A laminate according to one embodiment of the present invention is formed by laminating an insulating layer containing a cured product of the thermosetting resin composition or an insulating layer containing a cured product of the thermosetting resin composition, and a layer other than the insulating layer. A generally well-known laminate is a metal-clad laminate, and among them, a copper-clad laminate. A metal-clad laminate comprises an insulating layer containing or formed with a cured product of the thermosetting resin composition, and metal foils on both sides of said insulating layer. It may also be a single-sided metal-clad laminate in which metal foils are provided on only one side of the insulating layer. Furthermore, the insulating layer may contain a cured product of said thermosetting resin composition, may contain a cured product of the aforementioned prepreg, or may be a laminate formed by laminating multiple cured products of prepreg. Additionally, a copper-clad laminate may be manufactured using a copper foil attached to a resin, or it may be a metal-clad laminate in which a cured product of prepreg is first manufactured and a bonding film containing the thermosetting resin composition is interposed between the cured products to bond a metal foil.

[0137] The method for manufacturing such a laminate is not particularly limited as long as it is a general method. For example, when using prepreg, a method of manufacturing a laminate can be described as a method in which one or more prepreg sheets are stacked, a metal foil such as copper foil is stacked on both or one side of the upper and lower surfaces, and the laminate is integrated by heat pressure molding.

[0138] A printed circuit board according to one embodiment of the present invention comprises a cured product of the thermosetting maleimide resin composition. The insulating layer of the metal-clad laminate used in the manufacture of the printed circuit board may be manufactured using the prepreg described above. The printed circuit board can be manufactured by performing circuit formation processing and multilayer bonding processing on the metal-clad laminate by means of known methods, such as perforation processing, metal plating processing, etching of a metal foil, etc.

[0139] When manufacturing a printed circuit board, the following steps may be further performed: (1) a process of drilling holes in the insulating layer, (2) a process of treating the insulating layer, and (3) a process of forming a conductor layer. These steps (1) and (3) may be performed according to various known methods used in the manufacture of printed circuit boards.

[0140] Process (1) is a process of drilling holes in the insulating layer, thereby forming holes such as via holes and through holes in the insulating layer. Depending on the composition of the resin composition used to form the insulating layer, for example, a drill, laser, plasma, etc., can be used for process (1). The dimensions and shape of the holes are determined according to the design of the printed circuit board.

[0141] Process (2) is a process for harmonizing the insulating layer. The insulating layer is harmonized while removing (desmearing) the remaining resin called smear generated in process (1). The sequence and conditions of the harmonizing treatment are not particularly limited, and known sequences and conditions used to form the insulating layer of a printed circuit board may be adopted. For example, the insulating layer can be harmonized by performing swelling treatment with a swelling liquid, harmonizing treatment with an oxidizing agent, and neutralization treatment with a neutralizing liquid in this order.

[0142] The swelling solution used for the swelling treatment is not particularly limited, but examples include alkaline solutions and surfactant solutions, and preferably, an alkaline solution. These may be commercially available solutions, and examples of commercially available swelling solutions include "Swelling Deep Securigant P," "Swelling Deep Securigant SBU," and "Swelling Deep Securigant P" manufactured by Atotech Japan. The swelling treatment using the swelling solution is not particularly limited, but, for example, can be performed by immersing the insulating layer in a swelling solution at 30 to 90°C for 1 to 20 minutes. From the perspective of suppressing the swelling of the resin of the insulating layer to an appropriate level, it is preferable to immerse the insulating layer in a swelling solution at 40 to 80°C for 5 to 15 minutes.

[0143] The oxidizing agent used for the oxidizing treatment is not particularly limited, but, for example, an alkaline permanganate aqueous solution in which potassium permanganate or sodium permanganate is dissolved in an aqueous solution of sodium hydroxide may be used. It is preferable to perform the oxidizing treatment using an oxidizing agent such as an alkaline permanganate aqueous solution by immersing the insulating layer in the oxidizing agent solution heated to 60 to 100°C for 10 to 30 minutes. In addition, the concentration of permanganate in the alkaline permanganate aqueous solution is preferably 5 to 10 mass%. These may be commercially available solutions, and examples of commercially available oxidizing agents include alkaline permanganate aqueous solutions such as "Concentrate Compact CP" and "Dosing Solution Securigant P" manufactured by Atotec Japan.

[0144] As the neutralizing solution used for the oxidizing treatment, an acidic aqueous solution is preferred, and as a commercially available product, for example, "Reduction Solution Securigant P" manufactured by Atotech Japan can be cited. Treatment with the neutralizing solution can be performed by immersing the treated surface, which has undergone oxidizing treatment with an oxidizing agent, in a neutralizing solution at 30 to 80°C for 1 to 30 minutes. In terms of workability, a method of immersing the object, which has undergone oxidizing treatment with an oxidizing agent, in a neutralizing solution at 40 to 70°C for 5 to 20 minutes is preferred.

[0145] Process (3) is a process for forming a conductor layer, and a conductor layer is formed on an insulating layer. The conductor material used for the conductor layer is not particularly limited. In a suitable embodiment, the conductor layer comprises one or more metals selected from the group consisting of gold, platinum, palladium, silver, copper, aluminum, cobalt, chromium, zinc, nickel, titanium, tungsten, iron, tin, and indium. The conductor layer may be a single metal layer or an alloy layer, and as an alloy layer, for example, a layer formed of two or more metal alloys selected from the above group (e.g., nickel-chromium alloy, copper-nickel alloy, and copper-titanium alloy) may be used. Among these, from the perspective of the universality of forming the conductor layer, cost, and ease of patterning, a single metal layer of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver, or copper, or an alloy layer of a nickel-chromium alloy, a copper-nickel alloy, or a copper-titanium alloy is preferred, a single metal layer of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver, or copper, or an alloy layer of a nickel-chromium alloy is more preferred, and a single metal layer of copper is even more preferred.

[0146] The conductor layer may have a single-layer structure, or a multilayer structure in which two or more single metal layers or alloy layers containing different types of metals or alloys are stacked. In the case where the conductor layer has a multilayer structure, the layer in contact with the insulating layer is preferably a single metal layer of chromium, zinc, or titanium, or an alloy layer of a nickel-chromium alloy. The thickness of the conductor layer depends on the design of the desired printed circuit board, but is generally 3 to 35 μm, preferably 5 to 30 μm. Additionally, the conductor layer may be formed by plating.

[0147] Examples

[0148] The present invention is described in detail below with reference to examples and comparative examples, but the present invention is not limited to the following examples.

[0149] [(A) Maleimide resin having one or more hydrocarbon groups of dimer acid and / or trimer acid backbone in one molecule]

[0150] (A-1): Bismaleimide resin containing hydrocarbon groups derived from a dimer acid skeleton represented by the following formula (SLK-2600, manufactured by Shin-Etsu Chemical Co., Ltd., solid at 25°C)

[0151]

[0152] -C 36 H 70 - represents a structure derived from the dimer acid skeleton.

[0153] m ≈ 1, n ≈ 5

[0154] (A-2): Bismaleimide resin represented by the following formula (Trade name: BMI-5000, manufactured by Designer Molecules Inc., solid at 25°C)

[0155]

[0156] -C 36 H 70 - represents a hydrocarbon group derived from the dimer acid skeleton.

[0157] m ≈ 8 (average value)

[0158] (A-3): Bismaleimide resin represented by the following formula (Product name: SLK-1500, manufactured by Shin-Etsu Chemical Co., Ltd., syrup-like at 25℃)

[0159]

[0160] -C 36 H 70 - represents a hydrocarbon group derived from the dimer acid skeleton.

[0161] m ≈ 3 (average value)

[0162] (A-4): Bismaleimide resin represented by the following formula (Product name: SLK-6895, manufactured by Shin-Etsu Chemical Co., Ltd., liquid at 25℃)

[0163]

[0164] -C 36 H 70 - represents a hydrocarbon group derived from the dimer acid skeleton.

[0165] (A-5): 4,4'-Diphenylmethanebismaleimide (BMI-1000, manufactured by Daiwa Kasei Kogyo Co., Ltd., solid at 25℃, for comparison)

[0166] (A-6): Xylock-type polymaleimide resin (MIR-3000, manufactured by Nippon Kayaku Co., Ltd., solid at 25℃, for comparison)

[0167] [(B) Epoxy resin having two or more epoxy groups in one molecule]

[0168] (B-1): Bisphenol A type liquid epoxy resin (Product name: jER-828, manufactured by Mitsubishi Chemical Corporation)

[0169] (B-2): Aminophenol-type liquid epoxy resin (Product name: jER-630, manufactured by Mitsubishi Chemical Corporation)

[0170] [(C) Anionic polymerization initiator]

[0171] (C-1): 2-ethyl-4-methylimidazole (2E4MZ, manufactured by Shikoku Kasei Holdings Co., Ltd.)

[0172] (C-2): 2,4-diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-triazine (C11Z-A, manufactured by Shikoku Kasei Holdings Co., Ltd.)

[0173] (C-3): Dicumyl peroxide (Trade name: Percumyl D, manufactured by Nichiyu Co., Ltd., radical polymerization initiator for comparative example)

[0174] [(D) Chinese weapon filler]

[0175] (D-1): Hollow glass particles (Product Name: MG-005, manufactured by Taiheiyo Cement Co., Ltd., average particle size 1.6㎛, porosity 80% by volume) treated with an amino group-containing silane coupling agent (Product Name: KBM-573, manufactured by Shin-Etsu Chemical Co., Ltd.)

[0176] (D-2): Hollow silica particles (Product Name: HS-05, manufactured by Tokuyama Corporation, average particle size 0.5㎛, porosity 75% by volume) treated with an amino group-containing silane coupling agent (Product Name: KBM-573, manufactured by Shin-Etsu Chemical Co., Ltd.)

[0177] [(E) Solid Inorganic Filler]

[0178] (E-1): Spherical silica with an average particle size of 0.5㎛ treated with an amino group-containing silane coupling agent (Product name: KBM-573, manufactured by Shin-Etsu Chemical Co., Ltd.) (Product name: LVS-512H, manufactured by Tatsumori Co., Ltd.)

[0179] <Preparation and Compatibility of Resin Varnish>

[0180] With the formulations of Tables 1 and 2, each component other than component (C) shown in Tables 1 and 2 was added to a 500 mL four-necked flask equipped with a dim-loss condenser and a stirring device, and stirred at 80°C for 4 hours. After cooling to room temperature, component (C) was added and stirred at room temperature for 1 hour, and then filtered through a 100-mesh metal mesh to obtain a varnish-like resin composition. The following evaluation was performed using the obtained resin composition. The results are listed in Tables 1 and 2.

[0181] <Production and Handling Properties of Uncured Resin Films>

[0182] Regarding the fact that the resin varnish could be produced without problems in the above procedure, the resin varnish was coated onto a release-treated PET film (TN-010, manufactured by Toyobo STC) with a thickness of 50 μm using a roller coater, and dried at 100°C for 10 minutes to obtain an uncured resin film with a thickness of 50 μm. In evaluating the handling properties of the obtained uncured resin film, ○ was used when no overflow occurred from the uncured resin when the uncured resin film was cut with a cutter knife, △ was used when overflow occurred from the uncured resin, and × was used when cracking occurred when the uncured resin film was initially produced.

[0183] Non-permittivity, heritable tangent

[0184] The above uncured resin film was fixed as is on a flat plate together with a release-treated PET film, and a cured resin film was obtained by heating and curing at 200°C for 60 minutes. A strip line (manufactured by Keycom Co., Ltd.) was connected to a network analyzer (manufactured by Keysight, product name: E5063-2D5), and the relative permittivity and dielectric loss tangent of the cured resin film at frequencies of 10 and 40 GHz were measured.

[0185] <Coefficient of Thermal Expansion>

[0186] The coefficient of thermal expansion from 0 to 50°C of the cured resin film (thickness of 20 mm × 5 mm × 50 μm) produced above was measured and calculated using TMA 450 (manufactured by TA Instrument Co., Ltd.) at a heating rate of 5°C / min.

[0187] Tensile modulus, tensile strength, elongation

[0188] The cured resin film (50 μm thick) produced above was cut into a length of 10 cm × width of 1 cm. Then, the tensile modulus, tensile strength, and elongation of the cured resin film produced above were measured using a tensile strength measuring device (Autograph AGS-5kNG manufactured by Shimadzu Seisakusho).

[0189] Peel strength

[0190] A SUS304 plate with a length of 75 mm, a width of 25 mm, and a thickness of 1.0 mm was prepared, and the above-described uncured resin film with attached PET film was placed on one surface of the plate so that the resin film surface was in contact with it, and lamination was performed under conditions of 100°C, 0.3 MPa pressure, and 60 seconds. After lamination, the PET film was peeled off, and a copper foil with a thickness of 18 μm (Ra: 0.17 μm, Rz: 0.6 μm) was placed so that it was in contact with the resin film surface, and lamination was performed under conditions of 100°C, 0.3 MPa pressure, and 60 seconds. After lamination, an adhesion test specimen was prepared by heating and curing at 180°C for 60 minutes. To evaluate adhesion, the peel strength (kN / m) of each adhesive test specimen was measured when the copper foil was peeled off from a SUS304 plate under conditions of a temperature of 23°C and a tensile speed of 50 mm / min, in accordance with JIS C6481:1996 “Test method for copper-clad laminates for printed circuit boards.” In addition, the peel strength (kN / m) of the above-prepared test specimens after being left for 168 hours at a temperature of 85°C and a humidity of 85% was also measured in the same manner.

[0191]

[0192]

Claims

Claim 1 (A) Maleimide resin represented by the following formula (1) and solid at 25°C, (In Formula (1), A is independently a tetravalent organic group having a cyclic structure, B is independently a divalent hydrocarbon group having 6 to 60 carbon atoms, D is independently a divalent alicyclic hydrocarbon group having 6 to 200 carbon atoms or a hydrocarbon group derived from one or more selected from a dimerdiamine backbone and a trimertriamine backbone, and one or more of D are hydrocarbon groups derived from one or more selected from a dimerdiamine backbone and a trimertriamine backbone. m is 0 to 100, and n is 0 to 100. The order of each repeating unit grouped by m and n is not limited, and the bonding mode may be alternating, block, or random.) (B) an epoxy resin comprising two or more epoxy groups in one molecule, (C) an anionic polymerization initiator, and (D) a hollow inorganic filler, comprising a thermosetting maleimide resin composition. Claim 2 A thermosetting maleimide resin composition according to claim 1, wherein A in the above formula (1) is any of the tetravalent organic groups represented by the following formula. (A bonding hand in the above structural formula that is not bonded to a substituent is bonded to the carbonyl carbon forming the cyclic imide structure in the above formula (1).) Claim 3 A thermosetting maleimide resin composition according to claim 1, wherein the (C) anionic polymerization initiator is an imidazole compound having a triazine ring. Claim 4 A thermosetting maleimide resin composition according to claim 1, wherein the hollow inorganic filler of component (D) is one or more selected from hollow silica and hollow glass. Claim 5 A thermosetting maleimide resin composition according to claim 4, wherein the hollow inorganic filler of component (D) is treated with a silane coupling agent. Claim 6 A thermosetting maleimide resin composition according to claim 1, further comprising (E) a solid-phase inorganic filler as a component. Claim 7 A thermosetting maleimide resin composition, wherein the solid phase inorganic filler of component (E) is spherical silica with an average particle size of 0.1 to 5.0 μm. Claim 8 A bonding film comprising the thermosetting maleimide resin composition described in claim 1. Claim 9 A build-up film comprising the thermosetting maleimide resin composition described in claim 1. Claim 10 A resin-attached copper foil comprising a thermosetting maleimide resin composition as described in claim 1. Claim 11 A prepreg comprising the thermosetting maleimide resin composition described in claim 1. Claim 12 A laminate comprising the thermosetting maleimide resin composition described in claim 1. Claim 13 A printed circuit board using the material described in any one of paragraphs 8 through 12.

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