Resin composition, cured product, semiconductor element and dry film resist

Abstract

The present invention relates to a resin composition containing a maleimide resin that is compatible even when main skeletons differ from each other, and aims to provide a curable resin composition exhibiting excellent photocurability and heat resistance, and a cured product thereof. A curable resin composition having excellent compatibility, photocurability, and heat resistance is found by making a resin composition comprising: a bismaleimide compound (A) having a cyclic imide bond, which is obtained by reacting a specific aromatic diamine (a-1), a tetrabasic acid dianhydride (a-3), and maleic anhydride, and a bismaleimide compound (B) having a cyclic imide bond, which is obtained by reacting a specific aromatic diamine (a-1), a tetrabasic acid dianhydride (a-3), and maleic anhydride; and a maleimide compound (B) including a structure derived from a dimer diamine.

Description

Technical Field

[0001] The present invention relates to a photosensitive resin composition using a bismaleimide compound, or a cured product thereof and a semiconductor element. Background Art

[0002] In recent years, electronic devices have been miniaturized and have become more advanced, and in multilayer printed wiring boards, wiring has been required to be miniaturized and denser. Furthermore, in the next generation, materials for high-frequency bands are required, and as a noise countermeasure, transmission loss must be reduced, so there is a demand for the development of insulating materials with excellent dielectric properties.

[0003] In the past, polyimide resins, polybenzoxazole resins, etc. with excellent heat resistance or mechanical properties were widely used in surface protection films or interlayer insulating films of semiconductor elements (Patent Document 1). In the case where polyimide resins or polybenzoxazole resins are used as surface protection films or interlayer insulating films, it is known that there is a method of forming through holes by etching methods using positive photoresists containing these resins. However, the problem in the method is that complicated processes such as coating or stripping of photoresists are required. Therefore, for the purpose of rationalizing the operation process, heat-resistant materials with photosensitivity have been studied (Patent Document 2).

[0004] On the other hand, Patent Document 3 reports that a resin film made of a resin composition as a non-epoxy material, which contains a bismaleimide resin having a long-chain alkyl group and a curing agent, has excellent low dielectric properties.

[0005] Furthermore, Patent Documents 4 and 5 disclose polyimides using as raw materials dimer diamines derived from dimer acids, which are dimers of aromatic tetracarboxylic acids and unsaturated fatty acids such as oleic acid, and alicyclic diamines.

[0006] Patent Document 8 describes a resin composition containing a bismaleimide compound (curable resin) and a photoradical polymerization initiator (curing agent) as a photosensitivity resin composition for use in a laminate or a resin sheet.

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent Document 1: Japanese Patent Laid-Open No. 11-199557

[0010] Patent Document 2: Japanese Patent Laid-Open No. 11-24271

[0011] Patent Document 3: International Publication No. 2016 / 114287

[0012] Patent Document 4: Japanese Patent Application Publication No. 2017-119361

[0013] Patent Document 5: Japanese Patent Application Publication No. 2019-104843

[0014] Patent Document 6: WO2018 / 56466A1 Summary of the invention

[0015] Problems to be solved by the invention

[0016] Generally speaking, in order to improve the Tg of resin combination, in order to improve thermotolerance, the resin with ring structure is mostly used, but in the case described, due to the increase of the ring structure in the molecule, there is a tendency to reduce the solubility of the solvent. In addition, the compatibility of resins each other is also reduced, even if it is maleimide resins each other, it may not be compatible, particularly in the resin with a plurality of long-chain fatty chains and ring structure, generally incompatible combination. The poor thermotolerance of the hardened material formed by the resin combination using immiscible resins each other becomes the cause of cracking, and is therefore not suitable for the purposes such as protective film, interlayer insulating film, insulating film of the rewiring layer and bottom filling that can be used for semiconductor element and semiconductor substrate etc.

[0017] The film described in Patent Document 3 is essentially a combination of a bismaleimide resin having a long-chain alkyl group and a hard low-molecular aromatic maleimide, but has poor compatibility and is prone to uneven curing. In addition, the polyimide described in Patent Documents 4 and 5 is difficult to use when cured alone and has poor compatibility with other resins. In addition, the polyimide undergoes closed-loop dehydration during curing, so that, for example, when a redistribution layer is stacked, gaps may be generated and planarization may not be possible depending on the conditions of use.

[0018] In Patent Document 6, a bismaleimide compound is used as a curable resin, but maleimide compounds generally have poor light transmittance, so if a maleimide compound is included, light does not sufficiently reach the photocuring initiator, and the photocuring initiator is difficult to generate free radicals, and its reactivity is very low. Therefore, in Patent Document 3, the maleimide compound is cured by additional heating before development, but due to the accompanying heating, a high-definition resist pattern cannot be obtained.

[0019] The present invention has been made in view of such circumstances, and relates to a resin composition containing a maleimide resin that is compatible even when the main skeletons are different from each other, and an object of the present invention is to provide a curable resin composition showing excellent light curing property and heat resistance, and a cured product thereof.

[0020] By using two or more maleimide resins that are compatible even when their main skeletons are different from each other, the advantages of their main skeletons, namely, flexibility due to a long chain skeleton or high heat resistance due to having multiple ring structures, can be utilized, and a cured film can be produced only by light curing.

[0021] That is, the present invention relates to the following [1] to [7]. [1]

[0023] A resin composition comprises: a bismaleimide compound (A) having a cyclic imide bond, which is obtained by reacting an aromatic diamine (a-1) represented by the following formula (1), a tetrabasic acid dianhydride (a-3) and maleic anhydride; and a maleimide compound (B) comprising a structure derived from a dimer diamine.

[0024] [Chemistry 1]

[0025]

[0026] (R1 each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, a halogen atom, a hydroxyl group, or a linear or branched alkoxy group having 1 to 6 carbon atoms; l each independently represents an integer of 1 to 4) [2]

[0028] A resin composition comprising: a bismaleimide compound (A) represented by the following formula (2); and a maleimide compound (B) comprising a structure derived from a dimer diamine.

[0029] [Chemistry 2]

[0030]

[0031] (In formula (2), R 5 R3 is independently a divalent hydrocarbon group having 6 to 200 carbon atoms; R2 is independently represented by the following formula (3); R 4 R2 or R 4 ; m is 1 to 100, n is 0 to 100; in addition, the order of the repeating units enclosed by m and n is not limited, and the bonding pattern may be alternating, block, or random;

[0032] [Chemistry 3]

[0033]

[0034] (R6 each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, a halogen atom, a hydroxyl group, or a linear or branched alkoxy group having 1 to 6 carbon atoms; l each independently represents an integer of 1 to 4)) [3]

[0036] The resin composition according to technical solution 1 or 2 includes the bismaleimide compound (A) in which the tetrabasic acid dianhydride (a-3) comprises a compound selected from the group consisting of the following formula (4) to formula (12).

[0037] [Chemistry 4]

[0038]

[0039] (In formula (8), Y represents C(CF3)2, SO2, CO, an oxygen atom, a direct bond, or a divalent linking group represented by the following formula (13))

[0040] [Chemistry 5]

[0041] [4]

[0043] The resin composition according to Technical Solution 1 or 2 further comprises a photocuring initiator (C). [5]

[0045] A hardened material comprising the resin composition according to technical solution 1 or 2. [6]

[0047] A semiconductor element comprises a surface protection film, an interlayer insulating film, or an insulating film of a redistribution layer comprising the resin composition containing a bismaleimide compound according to technical solution 1 or 2. [7]

[0049] A dry film resist is obtained by sandwiching the resin composition containing the bismaleimide compound according to technical solution 1 or 2 with a substrate.

[0050] Effects of the Invention

[0051] According to the present invention, the curable resin composition has excellent solution stability and compatibility, and workability is greatly improved. Moreover, the cured product thereof is also excellent in light curing property and heat resistance compared with the cured product alone. DETAILED DESCRIPTION

[0052] Hereinafter, the present invention will be described in detail.

[0053] The resin composition of the present invention contains a bismaleimide compound (A) and a maleimide compound (B) having a structure derived from a dimer diamine (hereinafter, also referred to as a maleimide compound (B)).

[0054] <Bismaleimide compound (A)>

[0055] The bismaleimide compound (A) is a compound having two maleimide groups, and has an aromatic diamine (a-1) represented by the following formula (1) and a cyclic imide bond. This bismaleimide compound (A) is obtained by reacting an aromatic diamine (a-1), a tetrabasic acid dianhydride (a-3) and maleic anhydride. Furthermore, if necessary, a divalent organic diamine (a-2) having 6 to 200 carbon atoms other than the aromatic diamine (a-1) may be reacted.

[0056] [Chemistry 6]

[0057]

[0058] (R1 each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, a halogen atom, a hydroxyl group, or a linear or branched alkoxy group having 1 to 6 carbon atoms; l each independently represents an integer of 1 to 4)

[0059] The bismaleimide compound (A) is a bismaleimide compound represented by the following general formula (3).

[0060] [Chemistry 7]

[0061]

[0062] (In formula (2), R4 independently represents a tetravalent organic group containing a cyclic structure; R3 independently represents a divalent hydrocarbon group having 6 to 200 carbon atoms; R2 independently represents the following formula (3);

[0063] [Chemistry 8]

[0064]

[0065] (R6 each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, a halogen atom, a hydroxyl group, or a linear or branched alkoxy group having 1 to 6 carbon atoms; l each independently represents an integer of 1 to 4; R5 is R2 or R4; n is 0 to 100, and m is 1 to 100; in addition, the order of each repeating unit enclosed by n and m is not limited, and the bonding pattern may be alternating, block, or random)

[0066] In the above formula (1), R1 each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, a halogen atom, a hydroxyl group, or a linear or branched alkoxy group having 1 to 6 carbon atoms.

[0067] The linear or branched alkyl group having 1 to 6 carbon atoms is not particularly limited, and examples thereof include methyl, ethyl, n-propyl, isopropyl, butyl, isobutyl, sec-butyl, and tert-butyl. Of these, alkyl groups having 1 to 4 carbon atoms are preferred, and methyl, ethyl, n-propyl, and isopropyl are more preferred, in terms of excellent adhesion to chips and substrates, good solubility in solvents, low melting points, low water absorption, and good compatibility with other resins.

[0068] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0069] The linear or branched alkoxy group having 1 to 6 carbon atoms is not particularly limited, and examples thereof include methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, 2-methylpropoxy, 1-methylpropoxy, and tert-butoxy. Among these, alkoxy groups having 1 to 4 carbon atoms are preferred, and methoxy, ethoxy, n-propoxy, and isopropoxy are more preferred, in terms of excellent adhesion to chips and substrates, good solubility in solvents, low melting points, low water absorption, and good compatibility with other resins.

[0070] As R1, in addition to showing excellent adhesion to chips and substrates, etc., it also shows good solubility in solvents, low melting point, low water absorption, and good compatibility with other resins. Preferably it is a hydrogen atom, a methyl group, an ethyl group, a hydroxyl group, a methoxy group, and an ethoxy group, more preferably a hydrogen atom, a methyl group, and a hydroxyl group, and even more preferably a hydrogen atom.

[0071] In the formula (1), each l independently represents an integer of 1 to 4. As l, in order to exhibit excellent adhesion to chips and substrates, etc., as well as good solubility in solvents, low melting point, low water absorption, and good compatibility with other resins, it is preferred that all R1s are hydrogen atoms, and thus 4 is preferred.

[0072] Specific examples of the aromatic diamine (a-1) represented by the formula (1) include aromatic diamines such as m-xylylenediamine (the following formula (14)), p-xylylenediamine (the following formula (15)), and o-xylylenediamine (the following formula (16)). As a commercial product, m-xylylenediamine (MXDA: manufactured by Mitsubishi Gas Chemical Co., Ltd.) can be easily obtained. As the aromatic diamine (a-1) represented by the formula (1), m-xylylenediamine (the following formula (15)) is preferred.

[0073] [Chemistry 9]

[0074]

[0075] [Chemistry 10]

[0076]

[0077] [Chemistry 11]

[0078]

[0079] The maleimide compound of the present embodiment is not particularly limited as long as it exerts the effects of the present invention, but in terms of good solubility in solvents, low melting point, low water absorption and good compatibility with other resins, the weight average molecular weight is preferably 100 to 100,000, and more preferably 500 to 30,000. In addition, in the present embodiment, the so-called "weight average molecular weight" refers to the weight average molecular weight obtained by gel permeation chromatography (GPC) and converted to polystyrene standards.

[0080] Generally, the light transmittance of maleimide compounds is poor. Therefore, if the resin composition contains maleimide compounds, light will not fully reach the photocuring initiator dispersed in the resin composition, and the photocuring initiator is difficult to generate free radicals. Therefore, in general, the photoradical reaction of maleimide compounds is difficult to proceed, and even if the free radical polymerization or dimerization reaction of the maleimide monomer is carried out, its reactivity is very low. However, the maleimide compound of the present embodiment has excellent light transmittance because the maleimide group is bonded to the aromatic ring via a methylene group and the conjugation length is short. Therefore, light fully reaches the photocuring initiator, thereby efficiently causing the photoradical reaction of maleimide. In addition, when a chloroform solution containing the maleimide compound at 1% by mass is prepared and the light transmittance of the chloroform solution is measured using light with a wavelength of 405nm (h-ray), the transmittance is 3% or more, showing very excellent light transmittance. Therefore, for example, when a printed wiring board having a high-density and high-definition wiring formation (pattern) is manufactured using a direct writing exposure method, a photoradical reaction of maleimide is efficiently induced even when active energy rays including a wavelength of 405 nm (h-rays) are used.

[0081] When using active energy rays including a wavelength of 405 nm (h-rays), if the photocuring initiator does not absorb the light of the wavelength of 405 nm (h-rays) and generate free radicals, polymerization will not proceed. Therefore, in such a case, as the photocuring initiator described later, it is preferable to use a photocuring initiator whose absorbance at a wavelength of 405 nm (h-rays) is 0.1 or more and shows very excellent absorption to light of a wavelength of 405 nm (h-rays).

[0082] The maleimide compound of the present embodiment has excellent light transmittance as described above, and therefore, for example, when light with a wavelength of 405 nm is used, the light can sufficiently reach the photocuring initiator, and free radicals generated by the photocuring initiator can be used to carry out a free radical reaction, thereby enabling photocuring to be carried out in a resin composition containing a large amount of the maleimide compound.

[0083] Furthermore, since the cured product containing the resin composition of the present embodiment is excellent in light curing property, heat resistance, and thermal stability, a protective film and an insulating layer can be suitably formed.

[0084] In addition, the divalent organic diamine (a-2) other than the aromatic diamine (a-1) used for the synthesis of the bismaleimide compound (A) is independently a divalent hydrocarbon group having 6 to 200 carbon atoms, preferably 8 to 100, and more preferably 10 to 50 carbon atoms. Among them, it is preferably a branched divalent hydrocarbon group in which one or more hydrogen atoms in the divalent hydrocarbon group are substituted by an alkyl or alkenyl group having 6 to 200 carbon atoms, preferably 8 to 100, and more preferably 10 to 50 carbon atoms. The branched divalent hydrocarbon group may be any of a saturated aliphatic hydrocarbon group and an unsaturated hydrocarbon group, and may have an alicyclic structure or an aromatic ring structure in the middle of the molecular chain. As the branched divalent hydrocarbon group, specifically, hydrocarbon groups derived from diamines at both ends of the so-called dimer diamine can be cited. In addition, the so-called dimer diamine, as shown in the following formula (18) to formula (23), is a product obtained by replacing the two carboxyl groups of the dimer acid, which is a dimer of unsaturated fatty acids such as oleic acid, with primary amino groups (see Japanese Patent Laid-Open No. 9-12712, etc.). Specific examples of commercially available dimer diamines include PRIAMINE 1074 and PRIAMINE 1075 (both manufactured by Croda Japan Co., Ltd.), and Versamine 551 (manufactured by Cognis Japan Co., Ltd.). These can be used alone or in combination of two or more. The following is a non-limiting general formula of dimer diamine (in each formula, m+n=6 to 17 is preferred, p+q=8 to 19 is preferred, and the dotted line portion refers to a carbon-carbon single bond or a carbon-carbon double bond).

[0085] [Chemistry 12]

[0086]

[0087] In addition, the tetrabasic acid dianhydride (a-3) used for the synthesis of the bismaleimide compound (A) is not particularly limited as long as it has two anhydride groups in one molecule. Specific examples of the component (a-3) include: pyromellitic anhydride, ethylene glycol-bis(trimellitic anhydride), glycerol-bis(trimellitic anhydride) monoacetate, 1,2,3,4-butanetetracarboxylic anhydride, 3,3',4,4'-diphenylsulfonic acid tetracarboxylic anhydride, 3,3',4,4'-benzophenone tetracarboxylic anhydride, 3,3',4,4'-biphenyl tetracarboxylic anhydride, 3,3',4,4'-diphenyl ether tetracarboxylic anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methylcyclohexene-1,2-dicarboxylic anhydride, 3a,4,5,9b-tetrahydro-5-(tetrahydro- 2,5-dioxo-3-furyl)-naphtho[1,2-c]furan-1,3-dione, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, bicyclo(2,2,2)-oct-7-ene-2,3,5,6-tetracarboxylic dianhydride and bicyclo[2.2.2]octane-2,3,5,6-tetracarboxylic dianhydride, 5,5'-((propane-2,2-diylbis(4,1-phenylene))bis(oxy))bis(isobenzofuran-1,3-dione), 4,4'-oxydiphthalic anhydride, 4,4'-(hexafluoroisopropylidene)diphthalic anhydride, 4,4'-bisphenol A dianhydride, etc. Among them, 4,4'-oxydiphthalic anhydride, 4,4'-(hexafluoroisopropylidene)diphthalic anhydride, and 4,4'-bisphenol A dianhydride are preferred in terms of solvent solubility and adhesion to the substrate. These may be used alone or in combination of two or more.

[0088] From the viewpoint of solvent solubility of the finally obtained bismaleimide resin, the tetrabasic acid dianhydride (a-3) used for the synthesis of the bismaleimide compound (A) preferably contains a compound selected from the group consisting of the following formulae (4) to (12).

[0089] [Chemistry 13]

[0090]

[0091] In formula (7), Y represents C(CF3)2, SO2, CO, an oxygen atom, a direct bond or a divalent linking group represented by formula (13).

[0092] [Chemistry 14]

[0093]

[0094] The tetrabasic acid dianhydride (a-3) is preferably a tetrabasic acid dianhydride (a-3) represented by the following general formula (24).

[0095] [Chemistry 15]

[0096]

[0097] The tetrabasic acid dianhydride (a-3) is preferably a tetrabasic acid dianhydride (a-3) represented by the following general formula (24).

[0098] [Chemistry 16]

[0099]

[0100] The tetrabasic acid dianhydride (a-3) is preferably a tetrabasic acid dianhydride (a-3) represented by the following general formula (25).

[0101] [Chemistry 17]

[0102]

[0103] The tetrabasic acid dianhydride (a-3) is preferably a tetrabasic acid dianhydride (a-3) represented by the following general formula (26).

[0104] [Chemistry 18]

[0105]

[0106] The tetrabasic acid dianhydride (a-3) is preferably a tetrabasic acid dianhydride (a-3) represented by the following general formula (27).

[0107] [Chemistry 19]

[0108]

[0109] Furthermore, the bismaleimide compound (A) may be a bismaleimide compound obtained by reacting the aromatic diamine (a-1), an organic diamine (a-2) other than the aromatic diamine (a-1), the tetracarboxylic dianhydride (a-3) and the maleic anhydride. By copolymerizing the organic diamine (a-2) other than the aromatic diamine (a-1), it is possible to further improve the photocurability and crack resistance of the obtained cured product and control the required physical properties as required.

[0110] The organic diamine (a-2) other than the aromatic diamine (a-1) (hereinafter referred to as the organic diamine (a-2) as appropriate) refers to a diamine other than the diamine contained in the aromatic diamine (a-1). Such organic diamine (a-2) is not particularly limited, and examples thereof include aliphatic diamines such as 1,6-hexamethylenediamine; alicyclic diamines such as 1,4-diaminocyclohexane, 1,3-bis(aminomethyl)cyclohexane, isophoronediamine, and norbornene diamine; 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(aminomethyl)benzene, 1,3- Aromatic diamines such as bis(4-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, 1,4-diaminobenzene, 1,3-diaminobenzene, 2,4-diaminotoluene, and 4,4'-diaminodiphenylmethane; 4,4'-diaminodiphenyl sulfone; 3,3'-diaminodiphenyl sulfone; 4,4-diaminobenzophenone; 4,4-diaminodiphenyl sulfide; and 2,2-bis[4-(4-aminophenoxy)phenyl]propane. Of these, aliphatic diamines having 6 to 12 carbon atoms such as 1,6-hexamethylenediamine; and diaminocyclohexanes such as 1,3-bis(aminomethyl)cyclohexane, isophoronediamine, and norbornenediamine are more preferred from the viewpoint of obtaining a cured product having high heat resistance. When the bismaleimide compound (A) is obtained by using these organic diamines (a-2), one of these organic diamines (a-2) may be used alone, or two or more thereof may be used in combination.

[0111] In the resin composition, the content of the bismaleimide compound (A) is preferably 10% by weight or more and less than 95% by weight in the total amount of the curable resin composition, more preferably 40% by weight or more and less than 90% by weight, and further preferably 50% by weight or more and less than 90% by weight. The content of the bismaleimide compound (A) is preferably greater than the maleimide compound (B). In the case of the range, there is a tendency that the heat resistance becomes good while maintaining good light curability in terms of the physical properties of the cured product. In addition, the total amount of the curable resin composition does not include the amount of solvent.

[0112] <Method for producing bismaleimide compound (A)>

[0113] The method for producing the bismaleimide compound (A) is not particularly limited, and the bismaleimide compound (A) can be efficiently produced by, for example, the method shown below.

[0114] As a basic process, a bismaleimide compound can be obtained by synthesizing amic acid from tetrabasic acid dianhydride and diamine and performing ring-closing dehydration through step A, then reacting maleic anhydride to synthesize maleamic acid, and finally performing ring-closing dehydration to cap the molecular chain end with a maleimide group through step B.

[0115] In the production method, each step can be roughly divided into two types: a synthesis reaction of amic acid or maleamic acid and a ring-closing dehydration reaction, which are described in detail below.

[0116] In step A, first, amic acid is synthesized by reacting a specific tetrabasic acid dianhydride with a specific diamine. The reaction is generally carried out in an organic solvent (eg, a nonpolar solvent or a high-boiling-point aprotic polar solvent) at room temperature (25°C) to 100°C.

[0117] Next, the ring-closing dehydration reaction of the amic acid is carried out at 90° C. to 120° C. while removing the water produced as a by-product of the condensation reaction from the system. In order to promote the ring-closing dehydration reaction, an organic solvent (e.g., a nonpolar solvent, a high-boiling-point aprotic polar solvent, etc.) or an acid catalyst may be added.

[0118] Examples of organic solvents include toluene, xylene, anisole, biphenyl, naphthalene, N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), etc. These can be used alone or in combination of two or more. In addition, examples of acid catalysts include sulfuric acid, methanesulfonic acid, trifluoromethanesulfonic acid, etc. These can be used alone or in combination of two or more.

[0119] The molar ratio of diamine to tetrabasic acid dianhydride is preferably diamine / tetrabasic acid dihydrate = 2.5 to 1.02 / 1.0, more preferably diamine / tetrabasic acid dianhydride = 2.0 to 1.15 / 1.0. By mixing at such a ratio, a copolymer containing amino groups at both ends can be synthesized.

[0120] In step B, maleamic acid is synthesized by reacting the diamine having amino groups at both ends obtained in step B with maleic anhydride at room temperature (25°C) to 100°C, and finally, water in the system produced as a by-product is removed under the condition of 95°C to 120°C while performing ring-closing dehydration, thereby capping the molecular chain ends with maleimide groups, and the target bismaleimide compound can be obtained. If the capping reaction of the molecular chain ends with maleimide groups is performed at 120°C or below, side reactions or high molecular weight products are less likely to occur, so it is preferred.

[0121] According to such a production method, the obtained bismaleimide compound has a block copolymer structure, and thus the compatibility with the synthesized resin can be uniformly improved.

[0122] <Maleimide compound (B)>

[0123] The maleimide compound (B) has a divalent hydrocarbon group (b) derived from a dimer acid and a cyclic imide bond. The maleimide compound (B) is a maleimide compound other than the bismaleimide compound (A). Specifically, it does not contain the structure of formula (3). Such a maleimide compound (B) can be obtained by reacting a diamine (b-1) derived from a dimer acid, a tetracarboxylic dianhydride (b-2) and maleic anhydride.

[0124] The divalent hydrocarbon group (b) derived from the dimer acid refers to a divalent residue obtained by removing two carboxyl groups from the dicarboxylic acid contained in the dimer acid. In the present invention, the divalent hydrocarbon group (b) derived from the dimer acid can be introduced into the maleimide resin by reacting a diamine (b-1) obtained by replacing two carboxyl groups of the dicarboxylic acid contained in the dimer acid with amino groups, with tetracarboxylic dianhydride (b-2) and maleic anhydride described later to form an imide bond.

[0125] The dimer acid is preferably a dicarboxylic acid having 20 to 60 carbon atoms. As a specific example of the dimer acid, there can be cited a dimer acid obtained by dimerizing the unsaturated bonds of unsaturated carboxylic acids such as linoleic acid, oleic acid, and linolenic acid, and then distilling and refining. The dimer acid of the specific example mainly contains a dicarboxylic acid having 36 carbon atoms, and usually contains a tricarboxylic acid and a monocarboxylic acid having 54 carbon atoms, each of which is limited to about 5% by mass. The diamine (b-1) derived from the dimer acid (hereinafter referred to as the diamine (b-1) derived from the dimer acid as appropriate) is a diamine obtained by replacing the two carboxyl groups possessed by each dicarboxylic acid contained in the dimer acid with amino groups, and is usually a mixture. As such a diamine (b-1) derived from the dimer acid, for example, diamines such as [3,4-bis(1-aminoheptyl)6-hexyl-5-(1-octenyl)]cyclohexane, or diamines containing diamines in which the unsaturated bonds are saturated by further hydrogenating these diamines.

[0126] As the divalent hydrocarbon group (b) derived from dimer acid introduced into the maleimide resin using the diamine (b-1) derived from dimer acid, it is preferred that the residue after removing two amino groups from the diamine (b-1) derived from dimer acid. In addition, when the maleimide compound (B) is obtained using the diamine (b-1) derived from dimer acid, as the diamine (b-1) derived from dimer acid, one type may be used alone, or two or more types having different compositions may be used in combination. Furthermore, as such a diamine (b-1) derived from dimer acid, for example, a commercially available product such as "PRIAMINE 1074" (manufactured by Croda Japan Co., Ltd.) may also be used.

[0127] The tetracarboxylic dianhydride (b-2) is a tetracarboxylic dianhydride having an alicyclic structure adjacent to the acid anhydride group, and when the bismaleimide compound is prepared after the reaction, the tetracarboxylic dianhydride has a structure such that the portion adjacent to the imide ring becomes an alicyclic structure. If the portion adjacent to the imide ring becomes an alicyclic structure, other aromatic rings may be contained in the structure.

[0128] The maleimide compound (B) is preferably represented by the following formula (2). 5 and R 6 This is a structure derived from tetracarboxylic dianhydride (b-2).

[0129] [Chemistry 20]

[0130]

[0131] (In formula (28), R 7 represents a divalent hydrocarbon group (b) derived from a dimer acid, R 8 represents a divalent organic group (c) other than the divalent hydrocarbon group (b) derived from a dimer acid, R 9 represents any one selected from the group consisting of a divalent hydrocarbon group (b) derived from a dimer acid and a divalent organic group (c) other than the divalent hydrocarbon group (b) derived from a dimer acid, and R 9 and R 10 each independently represents one or more organic groups selected from a tetravalent organic group having 4 to 40 carbon atoms (preferably 6 to 40 carbon atoms) with a monocyclic or condensed polycyclic alicyclic structure, a tetravalent organic group having 8 to 40 carbon atoms linked to each other directly or via a crosslinked structure, and a tetravalent organic group having 8 to 40 carbon atoms and a semi-alicyclic structure including both an alicyclic structure and an aromatic ring; m is an integer of 0 to 30, n is an integer of 0 to 30, and R 10 and R 11 They may be the same or different)

[0132] The tetracarboxylic dianhydride (b-2) is preferably a tetracarboxylic dianhydride (b-2) having an alicyclic structure represented by the following formula (29). The tetracarboxylic dianhydride (b-2) having an alicyclic structure represented by the following formula (29) has an alicyclic structure adjacent to an acid anhydride group.

[0133] [Chemistry 21]

[0134]

[0135] (In formula (29), Cy is a tetravalent organic group having 4 to 40 carbon atoms and containing a hydrocarbon ring, and the organic group may also contain an aromatic ring)

[0136] The tetracarboxylic dianhydride (b-2) having an alicyclic structure represented by the formula (29) can be specifically represented by the following formula (3-c).

[0137] [Chemistry 22]

[0138]

[0139] (In formula (3-c), R 12 is a tetravalent organic group having 4 to 40 carbon atoms and containing a hydrocarbon ring, and the organic group may also contain an aromatic ring)

[0140] The tetracarboxylic dianhydride (b-2) may be a tetravalent organic group having 4 to 40 carbon atoms (preferably 6 to 40 carbon atoms) with a monocyclic or condensed polycyclic alicyclic structure, a tetravalent organic group having 8 to 40 carbon atoms in which organic groups having a monocyclic alicyclic structure are linked to each other directly or via a crosslinked structure, or a tetravalent organic group having 8 to 40 carbon atoms with a semi-alicyclic structure including both an alicyclic structure and an aromatic ring. Specific examples of the tetracarboxylic dianhydride (b-2) having an alicyclic structure include 1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA), 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, dianhydride, H-PMDA), 1,1'-bicyclohexane-3,3',4,4'-tetracarboxylic-3,4:3',4'-dianhydride, H-BPDA), 4-(2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic anhydride, 5-(2,5-dioxotetrahydrofuranyl)-3-methyl-3-cyclohexene-1,2- alicyclic tetracarboxylic dianhydrides such as dicarboxylic anhydride, bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, 2,3,4,5-tetrahydrofurantetracarboxylic dianhydride, 3,5,6-tricarboxy-2-norbornaneacetic dianhydride, or compounds in which the aromatic rings of these are substituted with an alkyl group or a halogen atom; and semialicyclic tetracarboxylic dianhydrides such as 1,3,3a,4,5,9b-hexahydro-5(tetrahydro-2,5-dioxo-3-furanyl)naphtho[1,2-c]furan-1,3-dione, or compounds in which the hydrogen atoms of the aromatic rings of these are substituted with an alkyl group or a halogen atom.

[0141] The tetracarboxylic dianhydride (b-2) is preferably a tetracarboxylic dianhydride (b-2) having an alicyclic structure represented by the following formula (30).

[0142] [Chemistry 23]

[0143]

[0144] The tetracarboxylic dianhydride (b-2) is preferably a tetracarboxylic dianhydride (b-2) having an alicyclic structure represented by the following formula (27).

[0145] [Chemistry 24]

[0146]

[0147] In addition to adding the tetracarboxylic dianhydride (b-2) with alicyclic structure, it is also possible to add an acid dianhydride without alicyclic structure or an acid dianhydride containing an aromatic ring adjacent to an acid anhydride group. In the total amount of acid dianhydrides, the lower limit of tetracarboxylic dianhydride (b-2) is preferably more than 40 mol%, and further preferably more than 80 mol%, particularly preferably more than 90 mol%. The upper limit can be less than 100 mol%. In the case where the content of tetracarboxylic dianhydride (a-2) in the total amount of acid dianhydrides is less than 40 mol%, the light-concentrating rate is low, and it is in a tendency that the opening of a small pattern cannot be obtained, so the resolution of the obtained pattern is reduced.

[0148] Specific examples of the acid dianhydride containing an aromatic ring adjacent to the acid anhydride group other than the tetracarboxylic dianhydride (b-2) include pyromellitic dianhydride, 4,4'-oxydiphthalic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,3,3',4'-biphenyltetracarboxylic dianhydride, 2,2',3,3'-biphenyltetracarboxylic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 2,2',3,3'-benzophenonetetracarboxylic dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 2,2-bis(2,3-dicarboxyphenyl)propane dianhydride, 1,1-bis(3,4-dicarboxyphenyl)ethane ... Aromatic tetracarboxylic acid dianhydrides such as 1-bis(2,3-dicarboxyphenyl)ethane dianhydride, bis(3,4-dicarboxyphenyl)methane dianhydride, bis(2,3-dicarboxyphenyl)methane dianhydride, 1,2,5,6-naphthalenetetracarboxylic acid dianhydride, 2,3,6,7-naphthalenetetracarboxylic acid dianhydride, 2,3,5,6-pyridinetetracarboxylic acid dianhydride, and 3,4,9,10-perylenetetracarboxylic acid dianhydride, or bis(3,4-dicarboxyphenyl)sulfone dianhydride, bis(3,4-dicarboxyphenyl)ether dianhydride, 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride, or compounds in which the aromatic rings of these compounds are substituted with an alkyl group or a halogen atom, and aromatic acid dianhydrides such as acid dianhydrides having an amide group. These may be used in combination with an acid dianhydride having an alicyclic structure or a semi-alicyclic structure having 4 to 40 carbon atoms.

[0149] Furthermore, the maleimide compound (B) may be a bismaleimide compound obtained by reacting the diamine (b-1) derived from a dimer acid, an organic diamine (b-3) other than the diamine (b-1) derived from a dimer acid, the tetracarboxylic dianhydride (b-2) and the maleic anhydride. By copolymerizing the organic diamine (b-3) other than the diamine (b-1) derived from a dimer acid, it is possible to control the required physical properties such as further reducing the tensile modulus of the obtained cured product as required.

[0150] The organic diamine (b-3) other than the diamine (b-1) derived from the dimer acid (hereinafter referred to as the organic diamine (b-3) as appropriate) refers to a diamine other than the diamine contained in the diamine (b-1) derived from the dimer acid. Such organic diamine (b-3) is not particularly limited, and examples thereof include aliphatic diamines such as 1,6-hexamethylenediamine; alicyclic diamines such as 1,4-diaminocyclohexane and 1,3-bis(aminomethyl)cyclohexane; 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(aminomethyl)benzene, 1,3-bis(4-aminophenoxy)benzene, Aromatic diamines such as 1,4-diaminobenzene, 1,3-bis(3-aminophenoxy)benzene, 1,4-diaminobenzene, 1,3-diaminobenzene, 2,4-diaminotoluene, and 4,4'-diaminodiphenylmethane; 4,4'-diaminodiphenyl sulfone; 3,3'-diaminodiphenyl sulfone; 4,4'-diaminobenzophenone; 4,4'-diaminodiphenyl sulfide; and 2,2-bis[4-(4-aminophenoxy)phenyl]propane. Of these, aliphatic diamines having 6 to 12 carbon atoms such as 1,6-hexamethylenediamine; diaminocyclohexanes such as 1,4-diaminocyclohexane; and aromatic diamines having an aliphatic structure having 1 to 4 carbon atoms in the aromatic skeleton such as 2,2-bis[4-(4-aminophenoxy)phenyl]propane are more preferred from the viewpoint of obtaining a cured product having a lower tensile elastic modulus. When the maleimide compound (B) is obtained by using these organic diamines (b-3), one of these organic diamines (b-3) may be used alone, or two or more thereof may be used in combination.

[0151] There are no particular limitations on the method for reacting the diamine (b-1) derived from a dimer acid, the tetracarboxylic dianhydride (b-2) having an alicyclic structure, and the maleic anhydride, or the method for reacting the diamine (b-1) derived from a dimer acid, the organic diamine (b-3), the tetracarboxylic dianhydride (b-2) having an alicyclic structure, and the maleic anhydride, and a known method can be appropriately adopted. For example, first, the diamine (b-1) derived from dimer acid, the tetracarboxylic dianhydride (b-2), and the organic diamine (b-3) as needed are stirred at room temperature (about 23°C) for 30 to 60 minutes in a solvent such as toluene, xylene, tetralin, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, or a mixed solvent thereof, thereby synthesizing polyamic acid, and then, maleic anhydride is added to the obtained polyamic acid, and stirred at room temperature (about 23°C) for 30 to 60 minutes, thereby synthesizing polyamic acid with maleic acid added to both ends. A solvent such as toluene that azeotropes with water is further added to the polyamic acid, and the water generated by imidization is removed while being refluxed at a temperature of 100°C to 160°C for 3 to 6 hours, thereby obtaining the target bismaleimide compound (A). In addition, in this method, a catalyst such as pyridine or methanesulfonic acid may also be further added.

[0152] The mixing ratio of the raw materials in the reaction is preferably such that (the total number of moles of all diamines contained in the diamine (b-1) derived from the dimer acid and the organic diamine (b-3)): (the total number of moles of tetracarboxylic dianhydride (b-2) having an alicyclic structure + 1 / 2 of the number of moles of maleic anhydride) is 1: 1. In addition, when the organic diamine (b-3) is used, from the viewpoint of expressing the flexibility derived from the dimer acid and tending to obtain a cured product with a lower elastic modulus, the ratio (the number of moles of the organic diamine (b-3)) / (the number of moles of all diamines contained in the diamine (b-1) derived from the dimer acid) is preferably 1 or less, and more preferably 0.4 or less. In addition, when the organic diamine (b-3) is used, the polymerization form of the amic acid unit containing the diamine (b-1) derived from the dimer acid and the tetracarboxylic dianhydride (b-2) having an alicyclic structure and the amic acid unit containing the organic diamine (b-3) and the tetracarboxylic dianhydride (b-2) having an alicyclic structure may be random polymerization or block polymerization.

[0153] As the maleimide compound (B) obtained in this manner, a maleimide compound (B) represented by the following formula (2) is preferred.

[0154] [Chemistry 25]

[0155]

[0156] (In formula (28), R7 represents a divalent hydrocarbon group (b) derived from a dimer acid, R 8 represents a divalent organic group (c) other than the divalent hydrocarbon group (b) derived from a dimer acid, R 9 represents any one selected from the group consisting of a divalent hydrocarbon group (b) derived from a dimer acid and a divalent organic group (c) other than the divalent hydrocarbon group (b) derived from a dimer acid, and R 9 and R 10 each independently represents one or more organic groups selected from a tetravalent organic group having 4 to 40 carbon atoms (preferably 6 to 40 carbon atoms) with a monocyclic or condensed polycyclic alicyclic structure, a tetravalent organic group having 8 to 40 carbon atoms linked to each other directly or via a crosslinked structure, and a tetravalent organic group having 8 to 40 carbon atoms and a semi-alicyclic structure including both an alicyclic structure and an aromatic ring; m is an integer of 0 to 30, n is an integer of 0 to 30, and R 10 and R 11 They may be the same or different)

[0157] The divalent hydrocarbon group (b) derived from dimer acid in the formula (28) is as described above. In addition, the divalent organic group (c) other than the divalent hydrocarbon group (b) derived from dimer acid in the formula (2) refers to a divalent residue after removing two amino groups from the organic diamine (b-3). However, in the same compound, the divalent hydrocarbon group (b) derived from dimer acid and the divalent organic group (c) are not the same. Furthermore, the tetravalent organic group in the formula (2) refers to a tetravalent residue after removing two groups represented by -CO-O-CO- from the tetracarboxylic dianhydride.

[0158] In the formula (28), m is the number of repeating units containing the divalent hydrocarbon group (b) derived from the dimer acid (hereinafter, referred to as a structure derived from the dimer acid as appropriate), and represents an integer of 0 to 30. When the value of m exceeds the upper limit, there is a tendency that the solubility in the solvent is reduced, particularly the solubility in the developer during development described later is reduced. In addition, as the value of m, from the viewpoint of achieving suitable solubility in the developer during development, it is particularly preferably 0 to 10.

[0159] In the formula (28), n is the number of repeating units (hereinafter referred to as structures derived from organic diamines) containing the divalent organic group (c), and represents an integer of 0 to 30. When the value of n exceeds the upper limit, the flexibility of the obtained cured product deteriorates, and there is a tendency for the obtained cured product to become a hard and brittle resin. In addition, as the value of n, it is particularly preferred that it is 0 to 10 from the viewpoint of the tendency to obtain a cured product with a low elastic modulus.

[0160] Furthermore, when m in the formula (28) is 2 or more, R7 and R 10 The respective repeating units may be the same or different. In addition, when n in the formula (2) is 2 or more, R 8 and R 11 The respective repeating units may be the same or different. Furthermore, in the bismaleimide compound represented by the formula (2), the structure derived from the dimer acid and the structure derived from the organic diamine may be random or block.

[0161] In addition, when the maleimide compound (B) is obtained from the diamine (b-1) derived from the dimer acid, the maleic anhydride, the tetracarboxylic dianhydride (b-2) and, if necessary, the organic diamine (b-3), when the reaction rate is 100%, n and m are represented by the mixing molar ratio of all diamines contained in the diamine (b-1) derived from the dimer acid, the organic diamine (b-3), the maleic anhydride and the tetracarboxylic dianhydride (b-2). That is, (m+n):(m+n+2) is represented by (the total molar number of all diamines contained in the diamine (b-1) derived from the dimer acid and the organic diamine (b-3)):(the total molar number of maleic anhydride and tetracarboxylic dianhydride (b-2)), m:n is represented by (the molar number of all diamines contained in the diamine (b-1) derived from the dimer acid):(the molar number of the organic diamine (b-3)), and 2:(m+n) is represented by (the molar number of maleic anhydride):(the molar number of tetracarboxylic dianhydride (b-2)).

[0162] Furthermore, in the maleimide compound (B), the sum of m and n (m+n) in the formula (28) is preferably 2 to 30 from the viewpoint of obtaining a cured product having a lower elastic modulus. In addition, the ratio of m to n (n / m) is preferably 1 or less, and more preferably 0.4 or less, from the viewpoint of expressing the flexibility derived from the dimer acid and obtaining a cured product having a lower elastic modulus.

[0163] As the maleimide compound (B), one kind may be used alone, or two or more kinds may be used in combination.

[0164] The content of the maleimide compound (B) is preferably 3% by weight or more and less than 60% by weight in the total amount of the curable resin composition, more preferably 5% by weight or more and less than 50% by weight, and further preferably 10% by weight or more and less than 40% by weight. The content of the bismaleimide compound (A) is preferably greater than the maleimide compound (B). In the case of the above range, there is a tendency that the heat resistance becomes good while maintaining good light curability in terms of the physical properties of the cured product. In addition, the total amount of the curable resin composition does not include the amount of solvent.

[0165] The bismaleimide compound (A) and the maleimide compound (B) are characterized by excellent compatibility. In the present application, the term "compatible" means that when a curable resin composition is formed by uniformly mixing two or more resins, the haze of the solution is less than 50 when in a liquid state, and when a cured product is formed, the glass transition temperature (Tg) of the curable resin composition is measured at only one place. In other words, in the "incompatible" state, the haze is 50 or more when in a liquid state, and in a cured product, multiple Tgs can be measured even if the resins are uniformly mixed.

[0166] <Photopolymerization initiator (C)>

[0167] The photopolymerization initiator (C) is not particularly limited, and any photopolymerization initiator that has been used in the past can be appropriately used. Examples thereof include acetophenone, 2,2-dimethoxyacetophenone, p-dimethylaminoacetophenone, Michelle's ketone, diphenylethylenedione, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-propyl ether, benzoin isopropyl ether, benzoin n-butyl ether, benzyl dimethyl ketal, thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-hydroxy-2-methyl-1-phenyl-propane-1-one, and 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propane-1-one , 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl}-2-methyl-propane-1-one, 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropane-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, 1-[4-(phenylthio)phenyl]-1,2-octanedione, 2-(O-benzoyl oxime), ethyl ketone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-, 1-(O-acetyl oxime), 2,4-dimethylthioxanthone and the like photopolymerization initiators. As such a photopolymerization initiator (C), one kind may be used alone, or two or more kinds may be used in combination.

[0168] Among these, as the photopolymerization initiator (C), from the viewpoint that a fine pattern can be formed using a reduced projection exposure machine (stepper; light source wavelength: 365nm, 436nm) which is standardly used in the manufacturing process of a protective film of a semiconductor, etc., it is preferred to use a photopolymerization initiator that efficiently generates free radicals at an exposure wavelength of 310nm to 436nm (more preferably 365nm). In addition, maleimide groups generally do not use free radicals for homopolymerization, and mainly react with free radicals generated by a photopolymerization initiator to form a cross-linked structure by dimerization of bismaleimide compounds. Therefore, the inventors and others speculate that compared with acrylic compounds and the like generally used as photopolymerizable compounds, bismaleimide compounds are apparently lacking in reactivity. Therefore, from the viewpoint that free radicals can be generated more efficiently and the reactivity at an exposure wavelength of 310nm to 436nm (more preferably 365nm) becomes higher, as the photopolymerization initiator, a compound having an oxime structure or a thioxanthone structure is further preferred.

[0169] Examples of such photopolymerization initiators include 1,2-octanedione, 1-[4-(phenylthio)-, 2-(O-benzoyl oxime)] (manufactured by BASF Japan, "IRGACURE OXE-01"), ethyl ketone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-, 1-(O-acetyl oxime) (manufactured by BASF Japan, "IRGACURE OXE-02"), and 2,4-dimethylthioxanthone (manufactured by Nippon Kayaku Co., Ltd., "DETX-S") having a thioxanthone structure. Such photopolymerization initiators having a high ability to generate free radicals by light tend to have an excessively high reactivity and are difficult to control the reaction when used for photopolymerization of ordinary acrylic compounds, but can be suitably used in the present invention.

[0170] The content of the photocuring initiator (C) in the resin composition is preferably 0.1 to 50 parts by mass, more preferably 0.2 to 30 parts by mass, and even more preferably 0.3 to 10 parts by mass relative to 100 parts by mass of the total of the bismaleimide compound (A) and the maleimide compound (B), from the viewpoint of improving the compatibility with the bismaleimide compound (A) and the maleimide compound (B), allowing the photocuring of these to proceed sufficiently, making the exposed portion sufficiently insolubilized in terms of developability in an organic solvent, and obtaining a resin sheet capable of suppressing cracking.

[0171] <Organic solvent (G)>

[0172] In the resin composition of the present embodiment, an organic solvent may be contained as needed. If an organic solvent is used, the viscosity of the resin composition can be adjusted during preparation. There is no particular limitation on the type of organic solvent as long as it can dissolve a part or all of the resin in the resin composition.

[0173] Examples of such organic solvents include halogen solvents such as dichloromethane, chloroform, dichloroethane, and chlorobenzene; aprotic polar solvents such as dimethylformamide, dimethylacetamide, dimethyl sulfoxide, tetrahydrofuran, dioxane, and acetonitrile; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, and cyclohexanone; cellosolve solvents such as 2-ethoxyethanol and propylene glycol monomethyl ether; aliphatic alcohol solvents such as methanol, ethanol, propanol, isopropanol, and butanol; phenol solvents containing aromatic groups such as phenol and cresol; ester solvents such as ethyl lactate, methyl acetate, ethyl acetate, butyl acetate, isopentyl acetate, methyl methoxypropionate, methyl hydroxyisobutyrate, γ-butyrolactone, and propylene glycol monomethyl ether acetate; aromatic hydrocarbon solvents such as toluene and xylene, etc.

[0174] Among these, cyclopentanone, propylene glycol monomethyl ether acetate, and dimethylacetamide are preferred in terms of excellent solubility in other resins and compounds such as bismaleimide compound (A) and maleimide compound (B), and further photopolymerization initiator (C) and compound (D) containing one or more carboxyl groups, and easy preparation of varnish with good solubility. These organic solvents can also be used alone or in combination of two or more.

[0175] <Method for producing resin composition>

[0176] The resin composition of the present embodiment is prepared by appropriately mixing a bismaleimide compound (A), a resin or a compound (B), a photocuring initiator (C), a compound (D) containing one or more carboxyl groups, and optionally a filler, other resins, other compounds, and additives. The resin composition can be suitably used as a varnish when preparing a resin sheet of the present embodiment described later. In addition, the organic solvent used in the preparation of the varnish is not particularly limited, and its specific example is as described above.

[0177] As the filler, it is preferably insulating and does not hinder the permeability relative to the wavelength of 405nm (h-ray). As the filler, there is no particular limitation, for example, silicon dioxide (for example, natural silicon dioxide, fused silica, synthetic silicon dioxide, hollow silica, etc.), aluminum compounds (for example, diaspore, aluminum hydroxide, aluminum oxide, aluminum nitride, etc.), boron compounds (for example, boron nitride, etc.), magnesium compounds (for example, magnesium oxide, magnesium hydroxide, etc.), calcium compounds (for example, calcium carbonate, etc.), molybdenum compounds (for example, molybdenum oxide, zinc molybdate, etc.), barium compounds (for example, barium sulfate, barium silicate, etc.), talc (for example, natural talc, calcined talc, etc.), mica, glass (for example, short glass fiber, spherical glass, glass powder (for example, E glass, T glass, D glass, etc.), silicone powder, fluororesin filler, urethane resin filler, (meth) acrylic resin filler, polyethylene filler, styrene-butadiene rubber, and silicone rubber, etc. These fillers can be used alone or in combination of two or more.

[0178] Among these, preferably, one or more selected from the group consisting of silica, diaspore, barium sulfate, silicone powder, fluororesin fillers, urethane resin fillers, (meth)acrylic resin fillers, polyethylene fillers, styrene-butadiene rubber, and silicone rubber.

[0179] These fillers may be surface-treated with a silane coupling agent or the like described below.

[0180] In terms of improving the heat resistance of the cured product obtained by curing the resin composition in the present invention and obtaining good coating properties, preferably silicon dioxide, more preferably fused silica. As a specific example of silicon dioxide, SC2050-MB, SC1050-MLE, YA010C-MFN, and YA050C-MJA manufactured by Denka (stock) and Admatechs (stock) can be listed.

[0181] The particle size of the filler is not particularly limited, but is usually 0.005 μm to 100 μm, preferably 0.01 μm to 50 μm.

[0182] In the resin composition of the present invention, the content of the filler is not particularly limited. From the viewpoint of making the heat resistance of the cured product good, it is preferably set to 1000 parts by mass or less, more preferably to 500 parts by mass or less, and most preferably to 300 parts by mass or less, relative to 100 parts by mass of the resin solid component in the resin composition. In addition, when the filler is contained, the lower limit is not particularly limited. From the viewpoint of obtaining the effect of improving the coating properties, heat resistance and other properties, it is usually 1 part by mass relative to 100 parts by mass of the resin solid component in the resin composition.

[0183] The resin composition can be prepared by, for example, sequentially mixing the above components in a solvent and stirring the mixture sufficiently. The resin composition has excellent photocurability, and a cured product obtained from the resin composition has excellent heat resistance, thermal stability, and insulation reliability.

[0184] When manufacturing resin composition, known treatment (stirring, mixing, kneading treatment, etc.) for making each component uniformly dissolve or disperse can be carried out as needed. Specifically, by using a stirring tank equipped with a stirrer with appropriate stirring ability to carry out stirring and dispersing treatment, the dispersibility of each component in the resin composition can be improved. Stirring, mixing, and kneading treatment can be appropriately carried out using known devices such as stirring devices for the purpose of dispersion such as ultrasonic homogenizers, devices for the purpose of mixing such as three rollers, ball mills, bead mills, sand mills, and mixing devices of revolution or autogenous type. In addition, when preparing resin composition, organic solvents can be used as needed. About the type of organic solvent, as long as it can dissolve the resin in the resin composition, it is not particularly limited, and its specific example is as described above.

[0185] The resin composition can be suitably used as a varnish when making the resin sheet of the present embodiment described later. The varnish can be obtained by a known method. For example, the varnish can be obtained by the following method: relative to 100 parts by mass of the components other than the organic solvent in the resin composition of the present embodiment, 10 parts by mass to 900 parts by mass of an organic solvent are added, and the known mixing treatment (stirring, kneading treatment, etc.) is performed.

[0186] [use]

[0187] The resin composition can be preferably used for the purpose of the resin composition requiring insulation reliability. As purposes, for example, it can be used for photosensitive film, photosensitive film with support, prepreg, resin sheet, circuit substrate (laminated board purposes, multilayer printed wiring board purposes, etc.), solder resist, bottom filling (underfill) material, crystal bonding material, semiconductor sealing material, hole filling resin, and part embedding resin, etc. Among these, the resin composition can be suitably used as the insulating layer purpose of multilayer printed wiring board or solder resist purpose due to its excellent light curing, heat resistance and thermal stability.

[0188] [Hardened material]

[0189] The cured product is obtained by curing the resin composition of the present embodiment. The cured product can be obtained, for example, by melting or dissolving the resin composition in a solvent, pouring it into a mold, and curing it under normal conditions using light. Regarding the wavelength region of the light, it is preferably cured within a range of 100 nm to 500 nm, which is efficiently cured by a photopolymerization initiator or the like.

[0190] [Resin sheet]

[0191] The resin sheet of this embodiment is a resin sheet with a support, which has a support and a resin layer disposed on one or both sides of the support, and the resin layer contains a resin composition. The resin sheet can be manufactured by coating the resin composition on the support and drying it. The resin layer in the resin sheet has excellent heat resistance, thermal stability and insulation reliability.

[0192] The support may be a known one, but preferably a resin film. Examples of the resin film include polyimide film, polyamide film, polyester film, polyethylene terephthalate (PET) film, polybutylene terephthalate (PBT) film, polypropylene (PP) film, polyethylene (PE) film, polyethylene naphthalate film, polyvinyl alcohol film, and triacetyl acetate film. Among these, a PET film is preferred.

[0193] In order to facilitate peeling from the resin layer, the resin film is preferably coated with a peeling agent on the surface. The thickness of the resin film is preferably in the range of 5 μm to 100 μm, and more preferably in the range of 10 μm to 50 μm. If the thickness is less than 5 μm, there is a tendency that the support is easily broken when the support is peeled off before development, and if the thickness exceeds 100 μm, there is a tendency that the resolution when the support is exposed is reduced.

[0194] Furthermore, in order to reduce light scattering during exposure, the resin film is preferably a film having excellent transparency.

[0195] Furthermore, in the resin sheet according to the present embodiment, the resin layer may be protected by a protective film.

[0196] By protecting the resin layer side with a protective film, dust or the like can be prevented from adhering to the surface of the resin layer or from being damaged. As the protective film, a film made of the same material as the resin film can be used. The thickness of the protective film is preferably in the range of 1 μm to 50 μm, more preferably in the range of 5 μm to 40 μm. When the thickness is less than 1 μm, the operability of the protective film tends to be reduced, and if it exceeds 50 μm, the cheapness tends to be deteriorated. In addition, the protective film is preferably relatively small in adhesion between the resin layer and the support, and the adhesion between the resin layer and the protective film is small.

[0197] The method for producing the resin sheet of the present embodiment may be, for example, a method in which the resin composition of the present embodiment is applied to a support such as a PET film and the organic solvent is removed by drying to produce the resin sheet.

[0198] The coating method may be, for example, a known method using a roll coater, a comma coater, a gravure coater, a die coater, a rod coater, a lip coater, a knife coater, an extrusion coater, etc. Drying may be performed, for example, by heating in a dryer at 60° C. to 200° C. for 1 minute to 60 minutes.

[0199] The amount of organic solvent remaining in the resin layer is preferably 5% by mass or less relative to the total mass of the resin layer from the viewpoint of preventing diffusion of the organic solvent in subsequent steps. The thickness of the resin layer is preferably 1 μm to 50 μm from the viewpoint of improving workability.

[0200] The resin sheet can be preferably used for producing an insulating layer of a multilayer printed wiring board.

[0201] [Multilayer printed wiring board]

[0202] The multilayer printed wiring board of the present embodiment has an insulating layer and a conductor layer formed on one or both sides of the insulating layer, and the insulating layer contains a resin composition. For example, one or more resin sheets can be overlapped and hardened to obtain an insulating layer. The number of layers of the insulating layer and the conductor layer is not particularly limited, and the number of layers can be appropriately set according to the target use. In addition, the order of the insulating layer and the conductor layer is not particularly limited. As a conductor layer, it can be a metal foil used for various printed wiring board materials, for example, metal foils such as copper and aluminum can be listed. As a copper metal foil, copper foils such as rolled copper foil and electrolytic copper foil can be listed. The thickness of the conductor layer is generally 1μm to 100μm. Specifically, it can be manufactured by the following method.

[0203] [Lamination process]

[0204] In the lamination process, a vacuum laminator is used to laminate the resin layer side of the resin sheet on one or both sides of the circuit substrate. As the circuit substrate, for example, glass epoxy substrate, metal substrate, ceramic substrate, silicon substrate, semiconductor sealing resin substrate, polyester substrate, polyimide substrate, bismaleimide triazine (BT) resin substrate, and thermosetting polyphenylene ether substrate can be cited. In addition, the so-called circuit substrate refers to a substrate having a conductor layer (circuit) processed with patterns formed on one or both sides of the substrate. In addition, in a multilayer printed wiring board formed by alternately stacking a conductor layer and an insulating layer, a substrate in which a single side or both sides of the outermost layer of the multilayer printed wiring board become a conductor layer (circuit) processed with patterns is also included in the circuit substrate. In addition, the insulating layer stacked on the multilayer printed wiring board can be an insulating layer obtained by overlapping one or more of the resin sheets of the present embodiment and hardening, or it can be an insulating layer obtained by overlapping one or more of the resin sheets of the present embodiment and a known resin sheet different from the resin sheet of the present embodiment. In addition, the overlapping method of the resin sheet of the present embodiment and the known resin sheet that is different from the resin sheet of the present embodiment is not particularly limited. On the conductor layer surface, roughening treatment can also be implemented in advance by blackening treatment and / or copper etching. In the lamination process, when the resin sheet has a protective film, the protective film is peeled off and removed, and the resin sheet and the circuit substrate are preheated as needed, and the resin layer of the resin sheet is pressurized and heated while being crimped to the circuit substrate. In the present embodiment, the method that the resin layer of the resin sheet is laminated to the circuit substrate under reduced pressure by vacuum lamination can be suitably used.

[0205] The conditions of the lamination process are preferably, for example, a pressure bonding temperature (lamination temperature) of 50° C. to 140° C. and a pressure bonding pressure of 1 kgf / cm 2 ~15kgf / cm 2 , the pressing time is set to 5 seconds to 300 seconds, and the air pressure is set to 20 mmHg or less under reduced pressure for lamination. In addition, the lamination process can be a batch type or a continuous type using a roller. The vacuum lamination method can be performed using a commercially available vacuum laminator. As a commercially available vacuum laminator, for example, a two-stage build-up laminator (2stage build-up laminator) (trade name) manufactured by Nikko Materials (stock) can be cited.

[0206] [Exposure process]

[0207] In the exposure step, after the resin layer is provided on the circuit board in the lamination step, an active energy line as a light source is irradiated to a predetermined portion of the resin layer to cure the resin layer in the irradiated portion.

[0208] Irradiation can be performed through a mask pattern or by direct irradiation. Examples of active energy rays include ultraviolet rays, visible light rays, electron beams, and X-rays. The wavelength of the active energy rays is, for example, in the range of 200 nm to 600 nm. When ultraviolet rays are used, the irradiation amount is approximately 10 mJ / cm 2 ~1000mJ / cm 2 In addition, when a printed wiring board having a high-density and high-precision wiring formation (pattern) is manufactured using a stepper exposure method, it is preferable to use an active energy line having a wavelength of 365 nm (i-ray), for example. When using an active energy line having a wavelength of 365 nm (i-ray), the irradiation amount is approximately 10 mJ / cm 2 ~10,000mJ / cm 2 When a printed wiring board having a high-density and high-precision wiring formation (pattern) is manufactured by direct drawing exposure method, it is preferable to use an active energy line having a wavelength of 405nm (h-ray), for example. When using an active energy line having a wavelength of 405nm (h-ray), the irradiation amount is approximately 10mJ / cm 2 ~10,000mJ / cm 2 .

[0209] The exposure method via the mask pattern includes a contact exposure method in which the mask pattern is brought into close contact with the multilayer printed wiring board, and a non-contact exposure method in which parallel light is used for exposure without close contact. Either method can be used. In addition, when a support is present on the resin layer, exposure can be performed from the support, or exposure can be performed after the support is peeled off.

[0210] [Development process]

[0211] In this embodiment, a developing step may be included as necessary.

[0212] That is, when there is no support on the resin layer, after the exposure step, the un-photocured portion (unexposed portion) is removed by wet development and developed, thereby forming a pattern of the insulating layer. In addition, when there is a support on the resin layer, after the exposure step, the un-photocured portion (unexposed portion) is removed by wet development and developed, thereby forming a pattern of the insulating layer.

[0213] In the case of wet development, the developer is not particularly limited as long as it is a developer that selectively dissolves the unexposed portion. For example, organic solvents such as cyclohexanone, cyclopentanone, and γ-butyrolactone; alkaline developers such as tetramethylammonium hydroxide aqueous solution, sodium carbonate aqueous solution, potassium carbonate aqueous solution, sodium hydroxide aqueous solution, and potassium hydroxide aqueous solution can be used. These developers can also be used alone or in combination of two or more.

[0214] In addition, as a developing method, for example, it can be carried out by known methods such as dipping, coating, spraying, shaking dipping, brushing, scraping, etc. In pattern formation, these developing methods can also be used together as needed. In addition, as a developing method, it is suitable to use high-pressure spray because it will further improve the resolution. As the spray pressure when using the spray method, it is preferably 0.02MPa to 0.5MPa.

[0215] [Post-baking process]

[0216] After the exposure process or the development process, a post-baking process is performed to form an insulating layer (hardened material). As the post-baking process, there are ultraviolet irradiation processes using high-pressure mercury lamps, heating processes using clean ovens, etc., and these processes can also be used in combination. In the case of ultraviolet irradiation, the irradiation amount can be adjusted as needed, for example, 50mJ / cm 2 ~10,000mJ / cm 2 The heating conditions can be appropriately selected as needed, but are preferably in the range of 150°C to 300°C for 20 minutes to 180 minutes, and more preferably in the range of 200°C to 300°C for 30 minutes to 60 minutes.

[0217] [Conductor layer forming step]

[0218] After forming the insulating layer (hardened material), a conductor layer is formed on the surface of the insulating layer by dry plating. As dry plating, known methods such as evaporation, sputtering, and ion plating can be used. The evaporation method (vacuum evaporation method) is, for example, to place a multilayer printed wiring board in a vacuum container and heat and evaporate the metal, thereby forming a metal film on the insulating layer. The sputtering method is, for example, to place a multilayer printed wiring board in a vacuum container, introduce an inert gas such as argon and apply a DC voltage, so that the ionized inert gas collides with the target metal, and a metal film can be formed on the insulating layer by using the knocked-out metal.

[0219] Then, a conductor layer is formed by electroless plating or electrolytic plating, etc. As a method for subsequent pattern formation, for example, a subtractive method, a semi-additive method, etc. can be used.

[0220] [Sealing materials]

[0221] The sealing material of the present embodiment includes the resin composition of the present embodiment. As the manufacturing method of the sealing material, generally known methods can be appropriately applied, and there is no particular limitation. For example, the sealing material can be manufactured by mixing the resin composition of the present embodiment with various known additives or solvents generally used in the sealing material use using a known mixer. In addition, during mixing, the maleimide compound of the present embodiment, various additives, and the method for adding the solvent can appropriately apply generally known methods, and there is no particular limitation.

[0222] [Fiber-reinforced composite materials]

[0223] The fiber-reinforced composite material of the present embodiment comprises the resin composition of the present embodiment and reinforcing fibers. As reinforcing fibers, generally known ones can be used without particular limitation. For example, glass fibers such as E glass, D glass, L glass, S glass, T glass, Q glass, UN glass, NE glass, and spherical glass; carbon fibers; polyaramid fibers; boron fibers; poly-p-phenylene benzobisoxazole (PBO) fibers; high-strength polyethylene fibers; alumina fibers; silicon carbide fibers. There are no particular limitations on the form and arrangement of the reinforcing fibers, and they can be appropriately selected from fabrics, non-woven fabrics, felts, knitted fabrics, ribbons, unidirectional strands, rovings, and chopped materials. In addition, as the form of reinforcing fibers, preforms (those formed by stacking fabric base fabrics containing reinforcing fibers or sewing them together using sutures, or fiber structures such as three-dimensional fabrics or woven fabrics) can also be used.

[0224] As a method for manufacturing these fiber-reinforced composite materials, generally known methods can be appropriately applied without particular limitation. For example, liquid composite molding, resin film infusion, filament winding, hand lay-up, and pultrusion can be cited. Among these, the resin transfer molding method, which is one of the liquid composite molding methods, can pre-set raw materials other than preforms such as metal plates, foam cores, and honeycomb cores in the forming mold, so it can cope with various uses, so it can be preferably used in the case of mass production of composite materials with relatively complex shapes in a short time.

[0225] [Adhesive]

[0226] The adhesive of the present embodiment includes the resin combination of the present embodiment. As the manufacturing method of the adhesive, generally known methods can be appropriately applied, and are not particularly limited. For example, the adhesive can be manufactured by mixing the resin combination of the present embodiment with various known additives or solvents generally used in the adhesive purposes using a known mixer. In addition, during mixing, the maleimide compound of the present embodiment, various additives, and the method for adding the solvent can appropriately apply generally known methods, and are not particularly limited.

[0227] [Semiconductor devices]

[0228] The heat-resistant resin film formed by the resin composition can be used for electronic parts such as semiconductor devices or multilayer wiring boards, and organic electroluminescence (EL) display devices. Specifically, it is suitably used for passivation films of semiconductors, surface protection films of semiconductor elements, interlayer insulating films, insulating films of redistribution layers, interlayer insulating films of multilayer wiring for high-density mounting, interlayer insulating films of electronic parts such as inductors or surface acoustic wave (SAW) filters, and insulating films or planar layers of organic electric field light-emitting elements, but is not limited thereto, and various structures can be adopted.

[0229] The resin composition can also be used in the form of a dry film resist. That is, for the resin composition, after the compound and the composition are applied to the base film using a roll coater, a die coater, a blade coater, a rod coater, a gravure coater, etc., they are dried in a drying oven set at 45°C to 140°C, a predetermined amount of solvent is removed, or a cover film is stacked as needed, thereby making a dry film resist. At this time, the thickness of the resist on the base film is adjusted to 2μm to 200μm. As a base film and a cover film, for example, films of polyester, polypropylene, polyethylene, triacetyl cellulose (TAC), polyimide, etc. are used. Among these films, films treated with a silicone release agent or a non-silicone release agent can also be used as needed. If supplied as a dry film resist, the coating and drying processes on the support can be omitted, and the photosensitive resin composition can be used more simply.

[0230] Example

[0231] The present invention is described in more detail below based on examples and comparative examples, but the present invention is not limited to the following examples. In addition, the "parts" and "%" in the examples are based on mass. In addition, the compatibility and light curing properties, heat resistance (glass transition temperature (Tg)), and thermal stability (5% weight loss temperature (Td5)) in each example and comparative example were evaluated as follows.

[0232] The conditions for measuring the molecular weight are as follows.

[0233] Model: TOSOH HLC-8220GPC

[0234] Column: Super HZM-N

[0235] Eluent: tetrahydrofuran (THF); 0.35 ml / min, 40 °C

[0236] Detector: Differential refractometer (refractive index, RI)

[0237] Molecular weight standard: polystyrene

[0238] <Bismaleimide compound (A)>

[0239] Synthesis Example 1 (A-1)

[0240] In a 1L round-bottom flask equipped with a thermometer, reflux cooler, Dean-Stark device, powder inlet, nitrogen inlet device and stirring device, 165g of toluene and 165g of N-methylpyrrolidone were added. Next, 17.6g (0.16mol) of m-xylene diamine (manufactured by Mitsubishi Gas Chemical Co., Ltd.) and 29.9 (0.06mol) of PRIAMINE 1075 (manufactured by Croda Japan Co., Ltd.) were added, and then 20.9g (0.22mol) of methanesulfonic acid was slowly added to form a salt. Stir for about 10 minutes to mix, and then 4,4'-(hexafluoroisopropylidene) diphthalic anhydride (48.2g, 0.11mol) was slowly added to the stirred mixture. The mixture was heated to reflux for 6 hours to form an amine-terminated diimide. At this point, the theoretical amount of water generated from the condensation was obtained. The reaction mixture was cooled to below room temperature, and 25.5 g (0.26 mol) of maleic anhydride was added to the flask. The mixture was further refluxed for 8 hours to obtain the desired amount of generated water. After cooling to room temperature, the organic layer was washed with water (100 ml × five times), and the salt and unreacted raw materials were removed to obtain a varnish of the bismaleimide compound. Thereafter, the varnish was added dropwise to 1,000 g of methanol, thereby implementing a reprecipitation process, removing the solvent and drying it, thereby obtaining the target light brown solid bismaleimide compound 55 g (yield 55%, Mw = 3,700) (A-1).

[0241] Synthesis Example 2 (A-2)

[0242] The compound was synthesized by a known method using the method described in Example 1 of Japanese Patent Application Laid-Open No. 2021-123672.

[0243] In a 1L round-bottom flask equipped with a thermometer, reflux cooler, Dean-Stark device, powder inlet, nitrogen introduction device and stirring device, 268g of toluene and 268g of N-methylpyrrolidone are put into. Then, 49.0g (0.29mol) of isophorone diamine is added, and then 42.6g (0.44mol) of methanesulfonic acid is slowly added to form a salt. Stir for about 10 minutes and mix, then slowly add 48.3g (0.22mol) of pyromellitic anhydride to the stirred mixture. The mixture is heated to reflux for 6 hours to form an amine-terminated diimide. By this time, the theoretical amount of generated water from the condensation is obtained. The reaction mixture is cooled to below room temperature, and 15.6g (0.16mol) of maleic anhydride is added to the flask. The mixture is further refluxed for 8 hours to obtain the generated water of the desired amount. After cooling to room temperature, the organic layer was washed with water (100 ml x five times) to remove salts and unreacted raw materials to obtain a varnish of a bismaleimide compound. Thereafter, the varnish was dropped into 1,000 g of methanol to perform a reprecipitation step, and the solvent was removed and dried to obtain 83 g (yield 83%, Mw = 3,200) of the target light brown solid bismaleimide compound (A-2).

[0244] <Maleimide compound (B)>

[0245] As the maleimide compound (B), the following two compounds were prepared.

[0246] (B-1) Maleimide compound

[0247] Manufactured by Nippon Kayaku Co., Ltd., trade name "MIZ-001"

[0248] (B-2) Maleimide compound

[0249] Manufactured by Designer Molecules Inc., trade name "BMI-1500"

[0250] <Photopolymerization initiator (C)>

[0251] Ethyl ketone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-, 1-(O-acetyl oxime) (manufactured by BASF Japan, "IRGACURE OXE-02")

[0252] (Example 1 to Example 10 and Comparative Example 1 to Comparative Example 6)

[0253] The components (A) to (C) were blended in the amounts (parts by mass) shown in Table 1 and 103 parts by mass of cyclopentanone as an organic solvent (G), to prepare photosensitive resin compositions of Examples 1 to 10 and Comparative Examples 1 to 6.

[0254] <Characteristics Evaluation>

[0255] The following properties were measured for the produced curable resin composition and cured film.

[0256] [Compatibility]

[0257] The visual compatibility refers to the state of the curable resin composition after mixing components (A) to (G) and stirring. Good compatibility means that there is no precipitate and it can be coated on the substrate, while poor compatibility means that there is precipitate and it is difficult to coat on the substrate.

[0258] (Evaluation Criteria)

[0259] ○: No precipitates

[0260] ×: There is precipitate

[0261] [Film-forming properties]

[0262] First, the photosensitive resin composition obtained in each embodiment and comparative example is applied to a rolled copper foil (BHY-82F-HA-V2 (trade name), manufactured by JX Metal Co., Ltd.) having a thickness of 18 μm using an applicator, and then dried at a temperature of 80°C for 30 minutes to form a film-like photosensitive resin composition on the copper foil. The coating thickness of the photosensitive resin composition is adjusted so that the film thickness of the dried film-like photosensitive resin composition becomes 20 μm. A light source capable of irradiating active energy rays having a wavelength of 405 nm (h-rays) (Ultra-high pressure mercury lamp 500W MultiLight (MultiLight) (trade name) manufactured by USHIO (stock)) is used, with an exposure amount of 3000 mJ / cm 2 The film-like photosensitive resin composition was exposed, and then heated at 250° C. for 60 minutes in a nitrogen environment to cure, and then the copper foil was removed by etching to obtain a cured film. The case where a cured film was obtained was designated as curability ○, and the case where the film could not be removed in the etching process and the physical properties of the cured film were difficult to obtain was designated as film forming property ×.

[0263] [Glass transition temperature (Tg) evaluation]

[0264] The dynamic viscoelasticity of the cured product of the bismaleimide prepared as described above was measured using a dynamic viscoelasticity measuring device (DMA) (RSA-G2 manufactured by TA Instruments) (frequency 1 Hz, tensile mode, heating rate 5°C / min), and the glass transition temperature was obtained by the maximum value of the loss tangent (tanδ). Furthermore, from the perspective of compatibility, the tanδ peak waveform was verified and the number of peaks was counted. The results are shown in Table 1.

[0265] [Resistance to thermal decomposition]

[0266] The cured film prepared as described above was cut into 4 mm squares, 1.0 mg to 5.0 mg was weighed on a measuring pan, and the 5% weight loss rate (Td5) was measured under the conditions of an air flow rate of 100 mL / sec and a heating rate of 10°C / min. The measuring apparatus used was a thermogravimetric analysis / differential scanning calorimeter (TGA / DSC) 1 (manufactured by METTLER TOLEDO).

[0267] [Table 1]

[0268] Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2 Comparative Example 3 A-1 20 50 80 50 80 A-2 50 B-1 80 50 20 100 50 B-2 50 20 100 C 3 3 3 3 3 3 3 3 G 103 103 103 103 103 103 103 103 Compatibility ○ ○ ○ ○ ○ ○ ○ × Film making properties ○ ○ ○ ○ ○ ○ ○ Unable to make film Tg(℃) 91 111 164 75 166 71 45 Unable to determine Td5(℃) 325 349 352 345 358 312 315 Unable to determine

[0269] As is clear from the results shown in Table 1, by using the photosensitive resin composition of the present invention, compatibility and photocurability are good, and the heat resistance of the flexible maleimide compound or the photocurability of the aromatic maleimide compound can be improved.

[0270] Industrial Applicability

[0271] As described above, the present invention can produce a photocurable film using light, and can effectively utilize both the flexibility or high photocurability of the flexible maleimide and the heat resistance of the aromatic maleimide.

[0272] Therefore, the bismaleimide compound and the photosensitive resin composition of the present invention are very useful as a surface protective film of a semiconductor element, an interlayer insulating film, an insulating film of a redistribution layer, and the like.

Claims

1. A resin composition comprising: a bismaleimide compound (A) having a cyclic imide bond, which is obtained by reacting an aromatic diamine (a-1) represented by the following formula (1), a tetrabasic acid dianhydride (a-3) and maleic anhydride; and a maleimide compound (B) comprising a structure derived from a dimer diamine. [Chemistry 1] (R1 each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, a halogen atom, a hydroxyl group, or a linear or branched alkoxy group having 1 to 6 carbon atoms; l each independently represents an integer of 1 to 4.) 2. A resin composition comprising: a bismaleimide compound (A) represented by the following formula (2); and a maleimide compound (B) comprising a structure derived from a dimer diamine. [Chemistry 2] (In formula (2), R 5 R3 independently represents a tetravalent organic group having a cyclic structure derived from the tetrabasic acid dianhydride (a-3). R3 independently represents a divalent hydrocarbon group having 6 to 200 carbon atoms. R2 independently represents the following formula (3). 4 R2 or R 4 ; m is 1 to 100, and n is 0 to 100. In addition, the order of each repeating unit bracketed by m and n is not limited, and the bonding pattern may be alternating, block, or random. [Chemistry 3] (R6 each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, a halogen atom, a hydroxyl group, or a linear or branched alkoxy group having 1 to 6 carbon atoms. l each independently represents an integer of 1 to 4.) 3 . The resin composition according to claim 1 , comprising the bismaleimide compound (A) wherein the tetrabasic acid dianhydride (a-3) comprises a compound selected from the group consisting of the following formula (4) to formula (12). [Chemistry 4] (In formula (8), Y represents C(CF3)2, SO2, CO, an oxygen atom, a direct bond, or a divalent linking group represented by the following formula (13).) [Chemistry 5] The resin composition according to claim 1 or 2, further comprising a photohardening initiator (C).

5. A cured product comprising the resin composition according to claim 1 or 2. 6 . A semiconductor element comprising a surface protection film, an interlayer insulating film, or an insulating film for a redistribution layer comprising the resin composition according to claim 1 .

7. A dry film resist obtained by sandwiching the resin composition according to claim 1 or 2 between substrates.

Images