Maleimide resin, curable resin composition and its cured product

Abstract

To provide a maleimide resin exhibiting excellent low water absorption, heat resistance, and electric characteristics, and having good curability, a curable resin composition, and a cured product of the same.SOLUTION: A maleimide resin has repeating units of following formulae (a), (b), (c), and (d). In the formulae, R1-R6 each represent a hydrogen atom, a 1-10C hydrocarbon group, or a halogenated hydrocarbon group, l and m each represent a real number of 0-5, and n represents a real number of 0-4. Each N independently represents a real number of 1-20, and L, M, and O each represent a real number of 0-20.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a maleimide resin, a curable resin composition, and a cured product thereof. It is suitably used for semiconductor encapsulants, printed wiring boards, electrical and electronic components such as build-up laminates, lightweight high-strength materials such as carbon fiber reinforced plastics and glass fiber reinforced plastics, and 3D printing applications. Background Art

[0002] In recent years, due to the expansion of application fields of laminates carrying electrical and electronic components, the required properties for such laminates have become extensive and more sophisticated. Conventionally, it has been mainstream to mount semiconductor chips on metal lead frames, but semiconductor chips with high processing capacity such as central processing units (hereinafter referred to as CPUs) are increasingly mounted on laminates made of polymer materials.

[0003] In the fifth-generation communication system "5G", the development of which is currently accelerating, further increase in capacity and high-speed communication are expected. The demand for materials with low dielectric loss tangent is increasing, and a dielectric loss tangent of 0.005 or less at 1 GHz is required.

[0004] Furthermore, in the automotive field, digitalization is progressing, and precision electronic devices are sometimes arranged near engine driving units, so higher levels of heat resistance and moisture resistance are required. SiC semiconductors have begun to be used in trains, air conditioners, and the like, and extremely high heat resistance is required for encapsulants for semiconductor elements, so conventional epoxy resin encapsulants can no longer meet this requirement.

[0005] Against this background, polymer materials that can achieve both heat resistance and electrical properties have been studied. For example, Patent Document 1 proposes a composition containing a maleimide resin and a propenyl group-containing phenolic resin. However, phenolic hydroxyl groups that do not participate in the reaction remain during the curing reaction, so the electrical properties cannot be said to be sufficient.

[0006] Furthermore, 3D printing has attracted attention in recent years as a method of three-dimensional fabrication, and this 3D printing method is beginning to be applied in fields where reliability is required, such as aerospace, automobiles, and connectors for electronic components used in these applications. In particular, photocuring and thermosetting resins are being investigated for applications such as stereolithography (SLA) and digital light processing (DLP). Therefore, while conventional methods of transferring from molds mainly required shape stability and accuracy, 3D printing applications require a variety of properties such as heat resistance, mechanical properties, toughness, flame retardancy, and even electrical properties, and material development is progressing to meet these requirements. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 04-359911 [Overview of the project] [Problems that the invention aims to solve]

[0008] This invention has been made in view of the above circumstances, and aims to provide a maleimide resin, a curable resin composition, and a cured product thereof that exhibit excellent low water absorption, heat resistance, and electrical properties, and have good curability. [Means for solving the problem]

[0009] As a result of diligent research to solve the above problems, the inventors of the present invention have discovered that cured maleimide resins derived from amine compounds having a specific structure exhibit excellent low water absorption, heat resistance, and low dielectric properties, thus completing the present invention.

[0010] In other words, the present invention relates to the following [1] to [8]. [1] Maleimide resin having repeating units of the following formulas (a), (b), (c), and (d).

[0011] [ka]

[0012] (In the above formula, R1 to R6 represent hydrogen atoms, hydrocarbon groups with 1 to 10 carbon atoms, or halogenated hydrocarbon groups. l and m represent real numbers from 0 to 5, and n represents a real number from 0 to 4. N independently represents a real number from 1 to 20, and L, M, and O represent real numbers from 0 to 20. (a), (b), (c), and (d) are linked by *, and the repeating positions may be random.) [2] The maleimide resin according to the preceding paragraph [1], wherein in formulas (a), (b), and (c) above, R1 is a methyl group, R2 is a methyl group or a hydrogen atom, and R3 is a methyl group or a hydrogen atom. [3] The maleimide resin described in the preceding paragraph [1], wherein O is 0 in formula (d) above. [4] A curable resin composition containing the maleimide resin described in any one of the preceding paragraphs [1] to [3]. [5] Furthermore, the curable resin composition according to item [4] contains a curable resin other than the maleimide resin described in any one of the preceding items [1] to [3]. [6] Furthermore, the curable resin composition according to the preceding paragraph [4] or [5] contains a curing accelerator. [7] A cured product obtained by curing the maleimide resin described in the preceding paragraph [1]. [8] A cured product obtained by curing the curable resin composition described in the preceding paragraph [4]. [Effects of the Invention]

[0013] The maleimide resin of the present invention exhibits excellent curability, and its cured product has superior heat resistance and low dielectric properties. Therefore, it is a useful material for encapsulating electrical and electronic components, circuit boards, carbon fiber composites, and the like. Furthermore, curing the maleimide resin of the present invention on its own is also a preferred embodiment. [Brief explanation of the drawing]

[0014] [Figure 1] Shows the 1H-NMR chart of Synthesis Example 2. [Figure 2] Shows the 1H-NMR chart of Example 1. [Figure 3] Shows the 1H-NMR chart of Example 2. MODES FOR CARRYING OUT THE INVENTION

[0015] The maleimide resin of the present invention has repeating units represented by the following formulas (a), (b), (c) and (d).

[0016] [Chemical Formula]

[0017] (In the above formula, R1 to R6 each represent a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, or a halogenated hydrocarbon group. l and m each represent a real number of 0 to 5, n represents a real number of 0 to 4. Each N independently represents a real number of 1 to 20, and L, M and O each represent a real number of 0 to 20. Each of (a), (b), (c) and (d) is bonded via *, and the repeating positions may be random.)

[0018] In the formulas (a), (b), (c) and (d), R1 to R6 are each generally a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, or a halogenated hydrocarbon group, preferably a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms, and more preferably a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms. R1 is particularly preferably a methyl group or a hydrogen atom, and most preferably a methyl group. R2 and R3 are each particularly preferably a methyl group or a hydrogen atom, and most preferably a hydrogen atom. When R1 to R6 fall within the above ranges, molecular vibration is less likely to occur when exposed to high frequency, resulting in excellent electrical properties.

[0019] In formulas (a), (b), (c), and (d) above, l and m are usually between 0 and 5, preferably between 0 and 2, and more preferably 0. n and o are usually between 0 and 4, preferably between 0 and 2, and more preferably 0.

[0020] In formulas (a), (b), (c), and (d), L and M are between 0 and 20, preferably 1 as the lower limit, more preferably 1.1, and particularly preferably 2. Preferably 10 as the upper limit, and more preferably 5. In formulas (a), (b), (c), and (d), N is between 3 and 20, preferably 3.1 as the lower limit, and more preferably 5. Preferably 15 as the upper limit, and more preferably 10. If N is above the lower limit, the functional group density increases, and the heat resistance improves. On the other hand, if it is below the upper limit, the functional group density of the polar maleimide decreases, and the water absorption is reduced. In formulas (a), (b), (c), and (d), O is between 0 and 20, preferably 0 and 5, more preferably 0 and 2, and particularly preferably 0.

[0021] The weight-average molecular weight (Mw) of the maleimide resin having repeating units of formulas (a), (b), (c), and (d) (hereinafter also referred to as component (A)), determined by gel permeation chromatography (GPC), is preferably 200 or more and less than 20,000, more preferably 500 or more and less than 15,000, and particularly preferably 1,000 or more and less than 10,000. The number-average molecular weight (Mn) is preferably 200 or more and less than 10,000, more preferably 500 or more and less than 8,000, and particularly preferably 1,000 or more and less than 5,000. When the weight-average molecular weight and number-weight-average molecular weight are within the above ranges, purification by washing with water becomes easy, and the target compound does not volatilize during the solvent removal process.

[0022] Component (A) can be expressed as the following formula (1).

[0023] [ka]

[0024] (In formula (1), R1 to R6 represent hydrogen atoms, hydrocarbon groups with 1 to 10 carbon atoms, or halogenated hydrocarbon groups. l and m represent real numbers from 0 to 5, and n represents a real number from 0 to 4. N independently represents a real number from 3 to 20, and L, M, and O represent real numbers from 0 to 20. Although the repeating units are shown in a specific order for the sake of presentation, the position of each repeating unit can be random.)

[0025] Component (A) is obtained by reacting an amine compound having repeating units of the following formulas (a), (b), (d), and (e) (hereinafter also referred to as component (B)) with maleic acid or maleic anhydride.

[0026] [ka]

[0027] (In the above formula, R1 to R6 represent hydrogen atoms, hydrocarbon groups with 1 to 10 carbon atoms, or halogenated hydrocarbon groups. l and m represent real numbers from 0 to 5, and n represents a real number from 0 to 4. N independently represents a real number from 3 to 20, and L, M, and O represent real numbers from 0 to 20. (a), (b), (d), and (e) are linked by *, and the repeating positions may be random.)

[0028] The preferred ranges for R1 to R6, l, m, n, o, L, M, and N in formulas (a), (b), (d), and (e) are the same as those in formulas (a), (b), (c), and (d).

[0029] The weight-average molecular weight (Mw) of component (B), determined by gel permeation chromatography (GPC), is preferably 200 or more and less than 20,000, more preferably 500 or more and less than 15,000, and particularly preferably 1,000 or more and less than 10,000. The number-average molecular weight (Mn) is preferably 200 or more and less than 10,000, more preferably 500 or more and less than 8,000, and particularly preferably 1,000 or more and less than 5,000. When the weight-average molecular weight and number-weight-average molecular weight are within the above ranges, purification by washing with water becomes easier, and the target compound does not volatilize during the solvent removal process. The amine equivalent of component (B) is preferably 100 g / eq. or more and less than 3,000 g / eq., more preferably 200 g / eq. or more and less than 2,000 g / eq., and particularly preferably 300 g / eq. or more and less than 1,000 g / eq.

[0030] Examples of manufacturing methods for ingredient (B) are listed below, but are not limited to these. First, a polystyrene compound having a chloromethyl group is obtained by polymerizing a styrene monomer having a chloromethyl group and one or more styrene-based monomers by radical polymerization, cationic polymerization, or anionic polymerization. Any solvent, polymerization inhibitor, or living radical initiator may be added during this polymerization. Next, component (B) can be obtained by reacting the obtained polystyrene compound having a chloromethyl group with an aniline compound in the presence of an acidic catalyst. Any acid catalyst can be used in this reaction, but if necessary, hydrochloric acid, phosphoric acid, sulfuric acid, formic acid, p-toluenesulfonic acid, methanesulfonic acid, as well as Lewis acids such as aluminum chloride and zinc chloride, solid acids such as activated clay, acid clay, white carbon, zeolite, and silica alumina, and acidic ion exchange resins can be used. These may be used alone or in combination of two or more. From the viewpoint of simplicity of the manufacturing process and economic efficiency, reusable solid acids (solid acids such as activated clay, acid clay, white carbon, zeolite, and silica alumina, acidic ion exchange resins, etc.) can also be used. The amount of catalyst used is usually 0.1 to 0.8 moles per mole of the aniline compound used, preferably 0.2 to 0.7 moles. If there is too much, the viscosity of the reaction solution may become too high and stirring may become difficult, and if there is too little, the reaction may proceed slowly. When using the above-mentioned reusable solid acid catalyst, the amount of solid acid used is 1 to 50 wt%, preferably 5 to 40 wt%, and more preferably 10 to 30 wt%, relative to the amount of aniline compound charged. If the amount of solid acid used is greater than the above range, it becomes difficult to ensure the fluidity of the reaction solution, and if the amount of solid acid used is less than the above range, the reaction may not proceed sufficiently or the reaction time may be prolonged. The above reaction may be carried out using organic solvents such as toluene and xylene as needed, or without a solvent. For example, an acidic catalyst is added to a mixed solution of an aniline compound, a polystyrene compound having a chloromethyl group, and a solvent. If the catalyst contains water, the water is removed from the system by azeotropy. Then, the reaction is carried out at 40 to 180°C, preferably 50 to 170°C, for 0.5 to 20 hours. After that, the temperature is increased while removing water and low molecular weight components generated in the system by azeotropic dehydration to 180 to 300°C, preferably 190 to 250°C, more preferably 200 to 240°C, for 5 to 50 hours, preferably 5 to 20 hours. After the reaction is complete, the acidic catalyst is neutralized with an alkaline aqueous solution, and then a water-insoluble organic solvent is added to the oil layer and the washing is repeated until the wastewater becomes neutral. If the aforementioned reusable solid acid catalyst is used, the catalyst is removed by filtration.

[0031] The softening point of component (B) is preferably 80°C or lower, and more preferably 70°C or lower. A softening point of 80°C or lower prevents the viscosity of the maleimide-modified resin from becoming too high, making it easier to handle.

[0032] Component (B) can be expressed as the following formula (2).

[0033] [ka]

[0034] (In equation (2), R1 to R6 represent hydrogen atoms, hydrocarbon groups with 1 to 10 carbon atoms, or halogenated hydrocarbon groups. l and m represent real numbers from 0 to 5, and n represents a real number from 0 to 4. N independently represents a real number from 3 to 20, and L, M, and O represent real numbers from 0 to 20. Although each repeating unit is shown in a specific order for the sake of presentation, the position of each repeating unit can be random.)

[0035] Component (A) is obtained by reacting component (B) with maleic acid or maleic anhydride in the presence of a solvent and a catalyst. For example, the method described in Japanese Patent Publication No. 6429862 may be used. In this case, since it is necessary to remove the water generated during the reaction from the system, the solvent used in the reaction is water-insoluble. Examples of water-insoluble solvents include aromatic solvents such as toluene and xylene, aliphatic solvents such as cyclohexane and n-hexane, ethers such as diethyl ether and diisopropyl ether, ester solvents such as ethyl acetate and butyl acetate, and ketone solvents such as methyl isobutyl ketone and cyclopentanone, but are not limited to these, and two or more may be used in combination. In addition to the water-insoluble solvent, an aprotic polar solvent may also be used in combination. Examples include dimethyl sulfone, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, 1,3-dimethyl-2-imidazolidinone, and N-methylpyrrolidone, and two or more may be used in combination. When using an aprotic polar solvent, it is preferable to use one with a higher boiling point than the water-insoluble solvent used in combination. The catalyst is not particularly limited, but examples include acidic catalysts such as p-toluenesulfonic acid, hydroxy-p-toluenesulfonic acid, methanesulfonic acid, sulfuric acid, and phosphoric acid. For example, maleic acid is dissolved in toluene, and under stirring, an N-methylpyrrolidone solution other than component (B) is added, and then p-toluenesulfonic acid is added, and the reaction is carried out under reflux conditions while removing the water produced from the system.

[0036] The softening point of component (A) is preferably 170°C or lower, and more preferably 140°C or lower. A softening point of 170°C or lower facilitates heating and dissolution, making it easier to handle. While viscosity can be reduced by diluting with a solvent, this is undesirable because it limits its use to applications where solvents can be used.

[0037] Component (A) may contain a polymerization inhibitor. Examples of usable polymerization inhibitors include phenolic, sulfuric, phosphorusic, hindered amine, nitroso, and nitroxyl radical-based inhibitors. The polymerization inhibitor may be added during the synthesis of component (A) or after synthesis. Furthermore, polymerization inhibitors can be used alone or in combination of two or more. The amount of polymerization inhibitor used is typically 0.008 to 1 part by weight, preferably 0.01 to 0.5 parts by weight, per 100 parts by weight of the resin component. These polymerization inhibitors can be used individually, but two or more may be used in combination. In this invention, phenolic, hindered amine, nitroso, and nitroxyl radical-based inhibitors are preferred.

[0038] Specific examples of phenolic polymerization inhibitors include 2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-butyl-p-ethylphenol, stearyl-β-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, isooctyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, 2,4-bis-(n-octylthio)-6-(4-hydroxy-3, Monophenols such as 5-di-t-butylanilino)-1,3,5-triazine, 2,4-bis[(octylthio)methyl]-o-cresol; 2,2'-methylenebis(4-methyl-6-t-butylphenol), 2,2'-methylenebis(4-ethyl-6-t-butylphenol), 4,4'-thiobis(3-methyl-6-t-butylphenol), 4,4'-butylidenebis(3-methyl-6-t-butylphenol), Triethylene glycol-bis[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate], 1,6-hexanediol-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], N,N'-hexamethylenebis(3,5-di-t-butyl-4-hydroxyhydrocinnamamide), 2,2-thio-diethylenebis[3-(3,5-di-t-butyl-4-hydroxyphenyl] Bisphenols such as )propionate, 3,5-di-t-butyl-4-hydroxybenzylphosphonate-diethyl ester, 3,9-bis[1,1-dimethyl-2-{β-(3-t-butyl-4-hydroxy-5-methylphenyl)propionyloxy}ethyl]2,4,8,10-tetraoxaspiro[5,5]undecane, and bis(3,5-di-t-butyl-4-hydroxybenzylsulfonate ethyl)calcium;Examples of high molecular weight phenols include 1,1,3-tris(2-methyl-4-hydroxy-5-t-butylphenyl)butane, 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, tetrakis-[methylene-3-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate]methane, bis[3,3'-bis-(4'-hydroxy-3'-t-butylphenyl)butyric acid]glycol ester, tris-(3,5-di-t-butyl-4-hydroxybenzyl)-isocyanurate, 1,3,5-tris(3',5'-di-t-butyl-4'-hydroxybenzyl)-S-triazine-2,4,6-(1H,3H,5H)trione, and tocopherol.

[0039] Specific examples of sulfur-based polymerization inhibitors include dilauryl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, and distearylul-3,3'-thiodipropionate.

[0040] Specific examples of phosphorus polymerization inhibitors include triphenyl phosphite, diphenylisodecyl phosphite, phenyldiisodecyl phosphite, tris(nonylphenyl) phosphite, diisodecylpentaerythritol phosphite, tris(2,4-di-t-butylphenyl) phosphite, cyclic neopentanetetraylbis(octadecyl) phosphite, cyclic neopentanetetraylbi(2,4-di-t-butylphenyl) phosphite, and cyclic neopentanetetraylbi(2,4-di-t-butyl-4-methylphenyl) phosphite. Examples include phosphites such as bis[2-t-butyl-6-methyl-4-{2-(octadecyloxycarbonyl)ethyl}phenyl]hydrogen phosphite; and oxaphosphaphenanthrene oxides such as 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10-(3,5-di-t-butyl-4-hydroxybenzyl)-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, and 10-decyloxy-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide.

[0041] Specific examples of hindered amine polymerization inhibitors include, but are not limited to, Adekastab LA-40MP, Adekastab LA-40Si, Adekastab LA-402AF, Adekastab LA-87, Adekastab LA-82, Adekastab LA-81, Adekastab LA-77Y, Adekastab LA-77G, Adekastab LA-72, Adekastab LA-68, Adekastab LA-63P, Adekastab LA-57, Adekastab LA-52, Chimassorb2020FDL, Chimassorb944FDL, Chimassorb944LD, Tinuvin622SF, TinuvinPA144, Tinuvin765, Tinuvin770DF, TinuvinXT55FB, Tinuvin111FDL, Tinuvin783FDL, and Tinuvin791FB.

[0042] Specific examples of nitroso polymerization inhibitors include p-nitrosophenol, N-nitrosodiphenylamine, ammonium salts of N-nitrosophenylhydroxyamine, (cuperone), and preferably, ammonium salts of N-nitrosophenylhydroxyamine (cuperone).

[0043] Specific examples of nitroxyl radical polymerization inhibitors include, but are not limited to, TEMPO(2,2,6,6-tetramethylpiperidine 1-oxyl) free radicals and 4-hydroxy-TEMPO free radicals.

[0044] The curable resin composition of the present invention can use any known material as the curable resin other than component (A). Specifically, examples include phenolic resins, epoxy resins, amine resins, activated alkene-containing resins, isocyanate resins, polyamide resins, polyimide resins, cyanate ester resins, propenyl resins, metharyl resins, and activated ester resins, and these may be used individually or in combination of multiple types. Furthermore, from the perspective of balancing heat resistance, adhesion, and dielectric properties, it is preferable to include epoxy resins, activated alkene-containing resins, and cyanate ester resins. By including these curable resins, the brittleness of the cured product and the adhesion to metal can be improved, and cracks in the package during reliability tests such as solder reflow and thermal cycling can be suppressed. The amount of curable resin used is preferably 10 times or less by mass relative to component (A), more preferably 5 times or less by mass, and particularly preferably 3 times or less by mass. A preferred lower limit is 0.5 times or more by mass, and more preferably 1 time or more by mass. Using 10 times or less by mass allows the heat resistance and dielectric properties of component (A) to be utilized effectively.

[0045] Examples of phenolic resins, epoxy resins, amine resins, activated alkene-containing resins, isocyanate resins, polyamide resins, polyimide resins, cyanate ester resins, and activated ester resins can be used, as shown below.

[0046] Phenolic resins: Polycondensates of phenols (phenol, alkyl-substituted phenol, aromatic-substituted phenol, hydroquinone, resorcinol, naphthol, alkyl-substituted naphthol, dihydroxybenzene, alkyl-substituted dihydroxybenzene, dihydroxynaphthalene, etc.) and various aldehydes (formaldehyde, acetaldehyde, alkylaldehyde, benzaldehyde, alkyl-substituted benzaldehyde, hydroxybenzaldehyde, naphthaldehyde, glutaraldehyde, phthalaldehyde, crotonaldehyde, cinnamaldehyde, furfural, etc.), and phenols and various diene compounds (dicyclopentadiene, terpenes, vinylcyclohexene, norbornadiene, vinylnorbornene, tetrahydride) Polymers of loindene, divinylbenzene, divinylbiphenyl, diisopropenylbiphenyl, butadiene, isoprene, etc.; polycondensates of phenols and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone, benzophenone, etc.); phenol resins obtained by polycondensation of phenols and substituted biphenyls (4,4'-bis(chloromethyl)-1,1'-biphenyl and 4,4'-bis(methoxymethyl)-1,1'-biphenyl, etc.) or substituted phenyls (1,4-bis(chloromethyl)benzene, 1,4-bis(methoxymethyl)benzene and 1,4-bis(hydroxymethyl)benzene, etc.); polycondensates of bisphenols and various aldehydes; polyphenylene ethers.

[0047] Epoxy resins: Glycidyl ether epoxy resins obtained by glycidylating the aforementioned phenolic resins, alcohols, etc., alicyclic epoxy resins such as 4-vinyl-1-cyclohexene diepoxide and 3,4-epoxycyclohexylmethyl-3,4'-epoxycyclohexanecarboxylate, glycidylamine epoxy resins such as tetraglycidyldiaminodiphenylmethane (TGDDM) and triglycidyl-p-aminophenol, and glycidyl ester epoxy resins.

[0048] Amine resins: diaminodiphenylmethane, diaminodiphenylsulfone, isophoronediamine, naphthalenediamine, aniline novolac, orthoethylaniline novolac, aniline resin obtained by reaction of aniline with xylylene chloride, aniline and substituted biphenyls (such as 4,4'-bis(chloromethyl)-1,1'-biphenyl and 4,4'-bis(methoxymethyl)-1,1'-biphenyl) as described in Japanese Patent No. 6429862, or substituted phenyls (such as 1,4-bis(chloromethyl)benzene, 1,4-bis(methoxymethyl)benzene and 1,4-bis(hydroxymethyl)benzene).

[0049] Active alkene-containing resins: Polycondensates of the above-mentioned phenolic resin and halogenated compounds containing active alkenes (chloromethylstyrene, allyl chloride, methallyl chloride, acrylate chloride, allyl chloride, etc.), polycondensates of active alkene-containing phenols (2-allylphenol, 2-propenylphenol, 4-allylphenol, 4-propenylphenol, eugenol, isoeugenol, etc.) and halogenated compounds (4,4'-bis(methoxymethyl)-1,1'-biphenyl, 1,4-bis(chloromethyl)benzene, 4,4'-difluorobenzophenone, 4,4'-dichlorobenzophenone, 4,4'-dibromobenzophenone, cyanuryl chloride, etc.), epoxy resins Polycondensates of lipids or alcohols with substituted or unsubstituted acrylates (acrylates, methacrylates, etc.), maleimide resins (4,4'-diphenylmethanebismaleimide, polyphenylmethanemaleimide, m-phenylenebismaleimide, 2,2'-bis[4-(4-maleimidophenoxy)phenyl]propane, 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethanebismaleimide, 4-methyl-1,3-phenylenebismaleimide, 4,4'-diphenyletherbismaleimide, 4,4'-diphenylsulfonebismaleimide, 1,3-bis(3-maleimidophenoxy)benzene, 1,3-bis(4-maleimidophenoxy)benzene).

[0050] Isocyanate resins: Aromatic diisocyanates such as p-phenylenediisocyanate, m-phenylenediisocyanate, p-xylenediisocyanate, m-xylenediisocyanate, 2,4-tollylenediisocyanate, 2,6-tollylenediisocyanate, 4,4'-diphenylmethanediisocyanate, naphthalenediisocyanate, etc.; aliphatic or alicyclic diisocyanates such as isophorone diisocyanate, hexamethylenediisocyanate, 4,4'-dicyclohexylmethanediisocyanate, hydrogenated xylenediisocyanate, norbornenediisocyanate, lysinediisocyanate, etc.; polyisocyanates such as biuret compounds of one or more isocyanate monomers or isocyanate compounds obtained by trimerizing the above diisocyanate compounds; polyisocyanates obtained by urethane reaction of the above isocyanate compounds with polyol compounds.

[0051] Polyamide resin: A polymer primarily composed of one or more amino acids (6-aminocaproic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid, para-aminomethylbenzoic acid, etc.) and lactams (ε-caprolactam, ω-undecanelactam, ω-laurolactam); or a polymer primarily composed of one or more diamines and one or more dicarboxylic acids. Diamines: Aliphatic diamines such as ethylenediamine, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decanediamine, undecanediamine, dodecanediamine, tridecanediamine, tetradecanediamine, pentadecanediamine, hexadecanediamine, heptadecanediamine, octadecanediamine, nonadecanediamine, eicosanediamine, 2-methyl-1,5-diaminopentane, and 2-methyl-1,8-diaminooctane; alicyclic diamines such as cyclohexanediamine, bis-(4-aminocyclohexyl)methane, and bis(3-methyl-4-aminocyclohexyl)methane; aromatic diamines such as xylylenediamine, etc. Dicarboxylic acids: Aliphatic dicarboxylic acids such as oxalic acid, malonic acid, succicic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, undecanediic acid, and dodecanediic acid; aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, 2-chloroterephthalic acid, 2-methylterephthalic acid, 5-methylisophthalic acid, 5-sodium sulfoisophthalic acid, hexahydroterephthalic acid, and hexahydroisophthalic acid; alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid; dialkyl esters and dichlorides of these dicarboxylic acids.

[0052] Polyimide resin: A polycondensate of the aforementioned diamine and tetracarboxylic dianhydride. Tetracarboxylic acid dianhydrides: 4,4'-(hexafluoroisopropylidene)diphthalic acid anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-cyclohexene-1,2-dicarboxylic acid anhydride, pyromellitic acid dianhydride, 1,2,3,4-benzenetetracarboxylic acid dianhydride, 3,3',4,4'-benzophenonetetracarboxylic acid dianhydride, 2,2',3,3'-benzophenonetetracarboxylic acid dianhydride, 3,3',4,4'-biphenyltetracarboxylic acid dianhydride, 3,3',4,4'-diphenyl Sulfonetetracarboxylic dianhydride, 2,2',3,3'-biphenyltetracarboxylic dianhydride, methylene-4,4'-diphthalic acid dianhydride, 1,1-ethylidene-4,4'-diphthalic acid dianhydride, 2,2'-propyridene-4,4'-diphthalic acid dianhydride, 1,2-ethylene-4,4'-diphthalic acid dianhydride, 1,3-trimethylene-4,4'-diphthalic acid dianhydride, 1,4-tetramethylene-4,4'-diphthalic acid dianhydride, 1,5-pentamethylene-4,4'-diphthalic acid dianhydride, 4,4'-oxydiphthalic acid dianhydride , thio-4,4'-diphthalic acid dianhydride, sulfonyl-4,4'-diphthalic acid dianhydride, 1,3-bis(3,4-dicarboxyphenyl)benzene dianhydride, 1,3-bis(3,4-dicarboxyphenoxy)benzene dianhydride, 1,4-bis(3,4-dicarboxyphenoxy)benzene dianhydride, 1,3-bis[2-(3,4-dicarboxyphenyl)-2-propyl]benzene dianhydride, 1,4-bis[2-(3,4-dicarboxyphenyl)-2-propyl]benzene dianhydride, bis[3-(3,4-dicarboxyphenoxy)phenyl]methane dianhydride , bis[4-(3,4-dicarboxyphenoxy)phenyl]methane dianhydride, 2,2-bis[3-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride, 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride, bis(3,4-dicarboxyphenoxy)dimethylsilane dianhydride, 1,3-bis(3,4-dicarboxyphenyl)-1,1,3,3-tetramethyldisiloxane dianhydride, 2,3,6,7-naphthalenetetracarboxylic acid dianhydride, 1,4,5,8-naphthalenetetracarboxylic acid dianhydride, 1,2,5,6-Naphthalenetetracarboxylic dianhydride, 3,4,9,10-Perylenetetracarboxylic dianhydride, 2,3,6,7-Anthracenetetracarboxylic dianhydride, 1,2,7,8-Phenanthrenetetracarboxylic dianhydride, Ethylenetetracarboxylic dianhydride, 1,2,3,4-Butanetetracarboxylic dianhydride, 1,2,3,4-Cyclobutanetetracarboxylic dianhydride, Cyclopentanetetracarboxylic dianhydride, Cyclohexane-1,2,3,4-Tetracarboxylic dianhydride 1,1-ethylene-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, 1,1-ethylene-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, 1,1-ethylidene-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, 1,1-ethylidene-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, 1,1-ethylidene-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride Water, 2,2-propyridene-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, oxy-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, thio-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, sulfonyl-4,4'-bis(cyclohexane-1,2-dicarboxylic acid) dianhydride, bicyclo[2,2,2]octo-7-ene-2,3,5,6-tetracarboxylic acid dianhydride, rel-[1S,5R,6R]-3-oxabi Cyclo[3,2,1]octane-2,4-dione-6-spiro-3'-(tetrahydrofuran-2',5'-dione), 4-(2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid anhydride, ethylene glycol-bis-(3,4-dicarboxylic acid anhydride phenyl) ether, 4,4'-biphenylbis(trimellitic acid monoester anhydride), 9,9'-bis(3,4-dicarboxyphenyl)fluorene dianhydride.

[0053] Cyanate ester resins are cyanate ester compounds obtained by reacting phenol resins with cyanide halides. Specific examples include, but are not limited to, dicyanatebenzene, tricyanatebenzene, dicyanate naphthalene, dicyanate biphenyl, 2,2'-bis(4-cyanatephenyl)propane, bis(4-cyanatephenyl)methane, bis(3,5-dimethyl-4-cyanatephenyl)methane, 2,2'-bis(3,5-dimethyl-4-cyanatephenyl)propane, 2,2'-bis(4-cyanatephenyl)ethane, 2,2'-bis(4-cyanatephenyl)hexafluoropropane, bis(4-cyanatephenyl)sulfone, bis(4-cyanatephenyl)thioether, phenol novolac cyanate, and phenol-dicyclopentadiene cocondensates in which the hydroxyl groups have been converted to cyanate groups. Furthermore, the cyanate ester compound whose synthesis method is described in Japanese Patent Publication No. 2005-264154 is particularly preferred as a cyanate ester compound because it has excellent low hygroscopicity, flame retardancy, and dielectric properties. The cyanate resin may contain catalysts such as zinc naphthenate, cobalt naphthenate, copper naphthenate, lead naphthenate, zinc octoate, tin octoate, lead acetylacetonate, or dibutyltin maleate to trimerize the cyanate groups and form a sym-triazine ring as needed. The catalyst is typically used in an amount of 0.0001 to 0.10 parts by mass, preferably 0.00015 to 0.0015 parts by mass, per 100 parts by mass of the total mass of the curable resin composition.

[0054] Active ester resin: Compounds having one or more active ester groups per molecule can be used as curing agents for curable resins other than component (A), such as epoxy resins, as needed. Preferred active ester curing agents are compounds having two or more highly reactive ester groups per molecule, such as phenol esters, thiophenol esters, N-hydroxyamine esters, and esters of heterocyclic hydroxy compounds. Preferably, the active ester curing agent is obtained by a condensation reaction between at least one compound of a carboxylic acid compound and a thiocarboxylic acid compound and at least one compound of a hydroxy compound and a thiol compound. In particular, from the viewpoint of improving heat resistance, active ester curing agents obtained from a carboxylic acid compound and a hydroxy compound are preferred, and active ester curing agents obtained from at least one compound of a carboxylic acid compound, a phenol compound, and a naphthol compound are preferred. Examples of carboxylic acid compounds include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, and pyromellitic acid. Examples of phenol compounds or naphthol compounds include hydroquinone, resorcinol, bisphenol A, bisphenol F, bisphenol S, phenolphthalein, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m-cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, benzenetriol, dicyclopentadiene-type diphenol compounds, and phenol novolac. Here, "dicyclopentadiene-type diphenol compounds" refers to diphenol compounds obtained by the condensation of two phenol molecules with one dicyclopentadiene molecule. Preferred examples of active ester-based curing agents include active ester compounds containing a dicyclopentadiene-type diphenol structure, active ester compounds containing a naphthalene structure, active ester compounds containing an acetylated phenol novolac, and active ester compounds containing a benzoylated phenol novolac. Among these, active ester compounds containing a naphthalene structure and active ester compounds containing a dicyclopentadiene-type diphenol structure are more preferred. The term "dicyclopentadiene-type diphenol structure" refers to a divalent structural unit consisting of phenylene-dicyclopentylene-phenylene. Commercially available active ester curing agents include, for example, active ester compounds containing a dicyclopentadiene-type diphenol structure such as "EXB9451", "EXB9460", "EXB9460S", "HPC-8000-65T", "HPC-8000H-65TM", "EXB-8000L-65TM", and "EXB-8150-65T" (manufactured by DIC Corporation); and active ester compounds containing a naphthalene structure such as "EXB9416-70BK" (manufactured by DIC Corporation); and phenolic Examples of active ester compounds containing acetylated volacs include "DC808" (manufactured by Mitsubishi Chemical Corporation); active ester compounds containing benzoylated phenol novolacs include "YLH1026", "YLH1030", and "YLH1048" (manufactured by Mitsubishi Chemical Corporation); active ester curing agents that are acetylated phenol novolacs include "DC808" (manufactured by Mitsubishi Chemical Corporation); and phosphorus atom-containing active ester curing agents include "EXB-9050L-62M" manufactured by DIC Corporation.

[0055] The curable resin composition of the present invention can be further improved in curability by using a curing accelerator (curing catalyst) in combination. As a specific example of a curing accelerator that can be used, it is preferable to use a radical polymerization initiator for the purpose of promoting the self-polymerization of radically polymerizable curable resins such as olefin resins and maleimide resins, or radical polymerization with other components. Suitable radical polymerization initiators include ketone peroxides such as methyl ethyl ketone peroxide and acetylacetone peroxide, diacyl peroxides such as benzoyl peroxide, dialkyl peroxides such as dicumyl peroxide and 1,3-bis-(t-butylperoxyisopropyl)benzene, peroxyketals such as t-butyl peroxybenzoate and 1,1-di-t-butylperoxycyclohexane, α-cumyl peroxyneodecanoate, t-butyl peroxyneodecanoate, t-butyl peroxypivalate, 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate, t-amyl peroxy-2-ethylhexanoate, t-butyl peroxy-2-ethylhexanoate, and t-amyl peroxy-3,5,5-trimethylhexanoate. Known curing accelerators include, but are not limited to, alkyl peresters such as noate, t-butylperoxy-3,5,5-trimethylhexanoate, and t-amylperoxybenzoate; peroxycarbonates such as di-2-ethylhexyl peroxydicarbonate, bis(4-t-butylcyclohexyl)peroxydicarbonate, t-butylperoxyisopropyl carbonate, and 1,6-bis(t-butylperoxycarbonyloxy)hexane; organic peroxides such as t-butyl hydroperoxide, cumene hydroperoxide, t-butyl peroxyoctoate, and lauroyl peroxide; and azo compounds such as azobisisobutyronitrile, 4,4'-azobis(4-cyanovaleric acid), and 2,2'-azobis(2,4-dimethylvaleronitrile). Ketone peroxides, diacyl peroxides, hydroperoxides, dialkyl peroxides, peroxyketals, alkyl peresters, parkervonates, etc. are preferred, with dialkyl peroxides being more preferred.The amount of radical polymerization initiator added is preferably 0.01 to 5 parts by mass, and particularly preferably 0.01 to 3 parts by mass, per 100 parts by mass of the curable resin composition. If the amount of radical polymerization initiator used is too large, the molecular weight will not elongate sufficiently during the polymerization reaction.

[0056] The curable resin composition of the present invention may optionally contain or be used in combination with curing accelerators other than radical polymerization initiators. Specific examples of curing accelerators that can be used include imidazoles such as 2-methylimidazole, 2-ethylimidazole, and 2-ethyl-4-methylimidazole; tertiary amines such as 2-(dimethylaminomethyl)phenol and 1,8-diazabicyclo(5,4,0)undecene-7; phosphines such as triphenylphosphine; quaternary ammonium salts such as tetrabutylammonium salt, triisopropylmethylammonium salt, trimethyldecanylammonium salt, cetyltrimethylammonium salt, and hexadecyltrimethylammonium hydroxide. Examples include quaternary phosphonium salts such as triphenylbenzylphosphonium salt, triphenylethylphosphonium salt, and tetrabutylphosphonium salt (the counterions of the quaternary salts are halogens, organic acid ions, hydroxide ions, etc., with no particular specification, but organic acid ions and hydroxide ions are particularly preferred), tin octylate, and transition metal compounds (transition metal salts) such as zinc carboxylates (zinc 2-ethylhexanoate, zinc stearate, zinc behenate, zinc myristic acid) and zinc phosphate esters (zinc octyl phosphate, zinc stearyl phosphate, etc.). The amount of curing accelerator used is 0.01 to 5.0 parts by weight per 100 parts epoxy resin, as needed.

[0057] Furthermore, the curable resin composition of the present invention may also contain a phosphorus-containing compound as a flame retardant component. The phosphorus-containing compound may be a reactive or additive type. Specific examples of phosphorus-containing compounds include phosphate esters such as trimethyl phosphate, triethyl phosphate, tricresyl phosphate, trixyllenyl phosphate, cresyl diphenyl phosphate, cresyl-2,6-dixyllenyl phosphate, 1,3-phenylenebis(dixyllenyl phosphate), 1,4-phenylenebis(dixyllenyl phosphate), and 4,4'-biphenyl(dixyllenyl phosphate); 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10(2,5- Phosphanes such as dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide; phosphorus-containing epoxy compounds obtained by reacting epoxy resin with the active hydrogen of the phosphanes, red phosphorus, etc. are examples, but phosphate esters, phosphanes, or phosphorus-containing epoxy compounds are preferred, and 1,3-phenylenebis(dixyllenyl phosphate), 1,4-phenylenebis(dixyllenyl phosphate), 4,4'-biphenyl(dixyllenyl phosphate), or phosphorus-containing epoxy compounds are particularly preferred. The content of the phosphorus-containing compound is preferably in the range of (phosphorus-containing compound) / (total epoxy resin) of 0.1 to 0.6 (by weight). Below 0.1, the flame retardancy is insufficient, and above 0.6, there is a concern that it will adversely affect the hygroscopicity and dielectric properties of the cured product.

[0058] Furthermore, a light stabilizer may be added to the curable resin composition of the present invention as needed. Suitable light stabilizers include hindered amine light stabilizers (HALS). While not specifically limited to HALS, representative examples include the polycondensate of dibutylamine·1,3,5-triazine·N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl-1,6-hexamethylenediamine and N-(2,2,6,6-tetramethyl-4-piperidyl)butylamine, the polycondensate of dimethyl-1-(2-hydroxyethyl)-4-hydroxy-2,2,6,6-tetramethylpiperidine succinate, and poly[{6-(1,1,3,3-tetramethylbutyl)amino-1,3,5-triazine-2,4-diyl}{(2,2,6,6-tetramethyl-4-piperidyl)imino}hexamethylene{(2,2,6,6-tetramethyl-4-piperi Examples include bis(1,2,2,6,6-pentamethyl-4-piperidyl)[{3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl}methyl]butylmalonate, bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, bis(1-octyroxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, 2-(3,5-di-t-butyl-4-hydroxybenzyl)-2-n-butylmalonate bis(1,2,2,6,6-pentamethyl-4-piperidyl), etc. HALS may be used individually or in combination of two or more types.

[0059] Furthermore, the curable resin composition of the present invention may also contain a binder resin as needed. Examples of binder resins include, but are not limited to, but include butyral resins, acetal resins, acrylic resins, epoxy-nylon resins, NBR (nitrile butadiene rubber)-phenolic resins, epoxy-NBR resins, polyamide resins, polyimide resins, and silicone resins. The amount of binder resin added is preferably within a range that does not impair the flame retardancy and heat resistance of the cured product, preferably 0.05 to 50 parts by mass per 100 parts by mass of the resin component, and more preferably 0.05 to 20 parts by mass as needed.

[0060] Furthermore, the curable resin composition of the present invention may optionally contain powders such as fused silica, crystalline silica, porous silica, alumina, zircon, calcium silicate, calcium carbonate, quartz powder, silicon carbide, silicon nitride, boron nitride, zirconia, aluminum nitride, graphite, forsterite, steatite, spinel, mullite, titania, talc, clay, iron oxide asbestos, and glass powder, or inorganic fillers made from these in spherical or crushed form. In particular, when obtaining a curable resin composition for semiconductor encapsulation, the amount of the above-mentioned inorganic filler used is usually in the range of 80 to 92% by mass, preferably 83 to 90% by mass, of the curable resin composition.

[0061] Furthermore, known additives may be added to the curable resin composition of the present invention as needed. Specific examples of additives that can be used include polybutadiene and its modified products, modified acrylonitrile copolymers, polyphenylene ether, polystyrene, polyethylene, polyimide, fluororesin, silicone gel, silicone oil, surface treatment agents for fillers such as silane coupling agents, mold release agents, and colorants such as carbon black, phthalocyanine blue, and phthalocyanine green. The amount of these additives added is preferably 1,000 parts by mass or less, more preferably 700 parts by mass or less, per 100 parts by mass of the curable resin composition.

[0062] The curable resin composition of the present invention is obtained by uniformly mixing the above components in predetermined proportions. Pre-curing is typically performed at 130-180°C for 30-500 seconds, followed by post-curing at 150-200°C for 2-15 hours to ensure a sufficient curing reaction and obtain the cured product of the present invention. Alternatively, the components of the curable resin composition can be uniformly dispersed or dissolved in a solvent, and then cured after removing the solvent.

[0063] The curable resin composition obtained in this way possesses moisture resistance, heat resistance, and high adhesion. Therefore, the curable resin composition of the present invention can be used in a wide range of fields where moisture resistance, heat resistance, and high adhesion are required. Specifically, it is useful as a material for all electrical and electronic components such as insulating materials, laminates (printed wiring boards, BGA substrates, build-up substrates, etc.), encapsulating materials, and resists. In addition, it can be used in fields such as molding materials, composite materials, paint materials, adhesives, and 3D printing. In particular, its solder reflow resistance is beneficial in semiconductor encapsulation.

[0064] The semiconductor device is sealed with the curable resin composition of the present invention. Examples of semiconductor devices include DIP (Dual In-Line Package), QFP (Quad Flat Package), BGA (Ball Grid Array), CSP (Chip Size Package), SOP (Small Outline Package), TSOP (Thin Small Outline Package), and TQFP (Thin Quad Flat Package).

[0065] The method for preparing the curable resin composition of the present invention is not particularly limited, but may be done by simply uniformly mixing each component or by prepolymerization. For example, the curable resin of the present invention may be prepolymerized by heating in the presence or absence of a catalyst, and in the presence or absence of a solvent. Similarly, in addition to the curable resin of the present invention, prepolymerization may be performed by adding curing agents such as epoxy resins, amine compounds, maleimide compounds, cyanate ester compounds, phenolic resins, and acid anhydride compounds, and other additives. Mixing or prepolymerization of each component may be done using an extruder, kneader, roll, etc., in the absence of a solvent, and a reaction vessel with a stirring device may be used in the presence of a solvent.

[0066] For uniform mixing, the resin composition is kneaded using equipment such as a kneader, roll, or planetary mixer at a temperature in the range of 50 to 100°C. After pulverization, the resulting resin composition can be molded into cylindrical tablets using a molding machine such as a tablet machine, or into granular powder or powdered molded bodies. Alternatively, these compositions can be melted on a surface support and molded into sheets with a thickness of 0.05 mm to 10 mm to produce curable resin composition molded bodies. The resulting molded bodies are non-sticky at 0 to 20°C, and their fluidity and curability hardly decrease even after storage at -25 to 0°C for more than a week. The resulting molded body can be molded into a hardened product using a transfer molding machine or a compression molding machine.

[0067] The curable resin composition of the present invention can also be modified by adding an organic solvent to obtain a varnish-like composition (hereinafter simply referred to as varnish). The curable resin composition of the present invention can be dissolved in solvents such as toluene, xylene, acetone, methyl ethyl ketone, methyl isobutyl ketone, dimethylformamide, dimethylacetamide, and N-methylpyrrolidone as needed to form a varnish. This varnish can then be impregnated into a substrate such as glass fiber, carbon fiber, polyester fiber, polyamide fiber, alumina fiber, or paper, and the resulting prepreg can be heat-dried. The resulting prepreg can then be hot-press-molded to obtain a cured product of the curable resin composition of the present invention. In this case, the solvent used is typically in an amount that accounts for 10 to 70% by weight, preferably 15 to 70% by weight, of the mixture of the curable resin composition of the present invention and the solvent. If the composition is in liquid form, a cured product of the curable resin containing carbon fibers can also be obtained directly, for example, by the RTM (Resin Transfer Molding) method.

[0068] Furthermore, the curable composition of the present invention can also be used as a modifier for film-type compositions. Specifically, it can be used to improve flexibility and other properties in the B-stage. Such a film-type resin composition can be obtained as a sheet-like adhesive by applying the curable resin composition of the present invention as a curable resin composition varnish onto a release film, removing the solvent under heating, and then performing B-stage formation. This sheet-like adhesive can be used as an interlayer insulating layer in multilayer substrates and the like.

[0069] The curable resin composition of the present invention can be heated and melted to reduce viscosity, and then impregnated into reinforcing fibers such as glass fibers, carbon fibers, polyester fibers, polyamide fibers, and alumina fibers to obtain a prepreg. Specific examples include, but are not limited to, glass fibers such as E glass cloth, D glass cloth, S glass cloth, Q glass cloth, spherical glass cloth, NE glass cloth, and T glass cloth; inorganic fibers other than glass; poly(p-phenylene terephthalamide) (Kevlar®, manufactured by DuPont); fully aromatic polyamides; polyesters; and organic fibers such as poly(p-phenylene benzoxazole), polyimide, and carbon fibers. The shape of the substrate is not particularly limited, but examples include woven fabrics, nonwoven fabrics, rovings, and chopped strand mats. As for the weaving method of the woven fabric, plain weave, twill weave, etc., are known, and these can be appropriately selected and used depending on the intended application and performance. Furthermore, glass woven fabrics that have been opened or surface-treated with silane coupling agents are preferably used. The thickness of the base material is not particularly limited, but is preferably about 0.01 to 0.4 mm. Alternatively, a prepreg can be obtained by impregnating reinforcing fibers with the varnish and then heating and drying them.

[0070] The laminate of this embodiment comprises one or more of the above-mentioned prepregs. The laminate is not particularly limited as long as it comprises one or more of the above-mentioned prepregs, and may have any other layers. The method for manufacturing the laminate is not particularly limited and can be any generally known method as appropriate. For example, when forming a metal foil laminate, a multi-stage press, a multi-stage vacuum press, a continuous molding machine, an autoclave molding machine, etc., can be used, and the laminate can be obtained by laminating the above-mentioned prepregs together and heating and pressing them. At this time, the heating temperature is not particularly limited, but 65 to 300°C is preferred, and 120 to 270°C is more preferred. The pressurizing pressure is not particularly limited, but if the pressurizing pressure is too high it is difficult to adjust the solid content of the resin in the laminate and the quality is not stable, and if the pressurizing pressure is too low it becomes difficult to form air bubbles and the adhesion between the layers is poor, so 2.0 to 5.0 MPa is preferred, and 2.5 to 4.0 MPa is more preferred. The laminate of this embodiment can be suitably used as a metal foil laminate described later by comprising a layer made of metal foil. By cutting the above prepreg into the desired shape, laminating it with copper foil or other materials as needed, and then applying pressure to the laminate using methods such as press molding, autoclave molding, or sheet winding molding while heating and curing a curable resin composition, electrical and electronic laminates (printed wiring boards) and carbon fiber reinforced materials can be obtained.

[0071] The cured product of the present invention can be used in various applications such as molding materials, adhesives, composite materials, and paints. Because the cured product of the curable resin composition described in the present invention exhibits excellent heat resistance and dielectric properties, it is suitably used in electrical and electronic components such as encapsulants for semiconductor devices, encapsulants for liquid crystal display devices, encapsulants for organic EL devices, printed circuit boards, and build-up laminates, as well as in composite materials for lightweight, high-strength structural materials such as carbon fiber reinforced plastics and glass fiber reinforced plastics. [Examples]

[0072] Next, the present invention will be described in more detail with reference to examples. Hereinafter, unless otherwise specified, parts refer to parts by weight. However, the present invention is not limited to these examples. The various analytical methods used in the examples are described below. <Weight average molecular weight (Mw), number average molecular weight (Mn)> The calculation was performed using polystyrene standard solutions and converted to polystyrene equivalents. GPC: DGU-20A3R, LC-20AD, SIL-20AHT, RID-20A, SPD-20A, CTO-20A, CBM-20A (all manufactured by Shimadzu Corporation) Columns: Shodex KF-603, KF-602 x2, KF-601 x2) Linking eluent: tetrahydrofuran Flow rate: 0.5ml / min. Column temperature: 40℃ Detection: RI (Differential Refraction Detector) <Amine equivalent> In accordance with the method described in Annex A of JIS K-7236.

[0073] [Synthesis Example 1] Synthesis of N-hydroxymethylmaleimide (MI-OH) In a 3L three-necked flask, 97.07g (5.15mol) of maleimide was dispersed in 414.29g (1.11mol) of formalin at room temperature. 15.31ml of 5% NaOH was then added over 30 minutes using a dropping funnel. The mixture was then stirred until all solids were completely dissolved, after which recrystallization was started and continued by placing the flask in ice water. Once sufficient crystals had precipitated, the solution was filtered, washed with cold water, and dried to obtain 60.4g of N-hydroxymethylmaleimide (MI-OH).

[0074] [Synthesis Example 2] Synthesis of N-chloromethylmaleimide (MI-Cl) In a dry 5 L round-bottom flask equipped with a stirring bar, 88.2 g (1 equivalent) of MI-OH obtained in Synthesis Example 1 and 1441 mL of acetone were added and dissolved. Then, the flask was placed in an ice bath, and under a nitrogen atmosphere, 124.6 g (0.4 equivalent) of phosphorus trichloride was added using a syringe while stirring. The reaction was carried out under N2 at 0°C for 1.5 hours until no starting materials were observed by TLC (1:1 hexane / ethyl acetate). The acetone was removed from the resulting reaction mixture under reduced pressure using a rotary evaporator. The reaction was stopped when yellow crystals appeared in the system, and the resulting concentrate was poured into 2000 g of ice water to precipitate the crystals. The precipitated crystals were then filtered and washed with 1441 g of cold water to remove acidic impurities. The obtained crystals were further recrystallized with 200 g of a 1:1 toluene:hexane solution, filtered, and dried under vacuum at 35°C for 16 hours to obtain 219 g of N-chloromethylmaleimide (MI-Cl). The purity of the obtained N-chloromethylmaleimide (MI-Cl) was 88%. 1 The 1H-NMR chart is shown in Figure 1. Note that, before using the crystals in the subsequent polymer alkylation reactions, they were dried under vacuum for 3-4 hours before being used in the reactions.

[0075] [Synthesis Example 3] Synthesis of Styrene-Norbornene Copolymer (SNC) In a 250 ml round-bottom flask equipped with a stirring bar and an air-free adapter, 12 g (1 equivalent) of norbornene, 108 g (1 equivalent) of styrene, 0.152 g (0.001 equivalent) of nickel dichloride catalyst, and 200 ml of toluene were added and dissolved. Nitrogen was blown into the resulting suspension for 15 minutes and cooled to 0°C. 1.287 g (0.002 equivalents) of a 25 wt% toluene solution of ethylaluminum dichloride was added, and the mixture was stirred at room temperature for 4 hours. The resulting polymer solution was filtered and reprecipitation was performed in 2000 g of methanol with stirring. The resulting polymer powder was washed with 200 g of methanol and then dried in a vacuum oven at 50°C for 24 hours to obtain 112 g of styrene-norbornene copolymer as a white powder. The DSC-mediated Tg was 85°C, and the molecular weights determined by GPC analysis were Mn = 3800 g / mol and Mw = 4900 g / mol.

[0076] [Example 1] Synthesis of M-1 A three-necked flask equipped with a stirring bar was heated, then cooled in the presence of nitrogen. After purging the system with nitrogen, 100 g (1 equivalent) of poly(styrene-co-α-methylstyrene), manufactured by Aldrich, and 12,000 mL of dichloromethane were added and completely dissolved. A mixture of 48.91 g (0.35 equivalent) of MI-Cl obtained in Synthesis Example 2 and 21.24 g (0.1 equivalent) of trichloroindium was then charged in the presence of nitrogen. The temperature was then raised to 40°C and the mixture was stirred under a nitrogen atmosphere for 18 hours. After the reaction was complete, the resulting reaction mixture was passed through a 200 g short column of high-purity silica gel (particle size: 63-200 μm, average pore size: 60 Å), and the resulting solution was concentrated in a rotary evaporator until the solution volume reached 800 mL. The resulting concentrate was poured into 10 L of methanol prepared in advance and reprecipitation was performed. The precipitated material was collected by filtration, washed with methanol, and dried in a vacuum oven at 45°C for 24 hours to obtain 76 g of the maleimide resin (M-1) of the present invention. 1 The H-NMR chart is shown in Figure 2. 1 ¹H-NMR confirmed that the sample contained 26 mol% maleimide groups.

[0077] [Example 2] Synthesis of M-2 A 2L three-necked flask equipped with a stirring bar was heated and cooled under nitrogen. 80g (1 equivalent) of SNC obtained in Synthesis Example 3, containing 12 mol% 2-norbornene units, was added to the flask with stirring until completely dissolved in 800ml of dichloromethane. 39.35g (0.4 equivalent) of MI-Cl obtained in Synthesis Example 2 and 14.95g (0.1 equivalent) of indium trichloride were added, and the flask was filled with nitrogen. The internal temperature of the flask was raised to 40°C, and the mixture was stirred under a nitrogen atmosphere for 18 hours to complete the alkylation. The polymer product was precipitated in a stirring vessel of excess methanol (2.5L) and filtered. The obtained polymer powder was washed with methanol and then dried in a vacuum oven at 50°C for 24 hours to obtain 63g of the maleimide resin (M-2) of the present invention as a white powder. GPC analysis revealed molecular weights of Mn = 3800g / mol and Mw = 4900g / mol. 1 The H-NMR chart is shown in Figure 3. 10 g of the obtained maleimide resin and 0.1 g of Luperox 101 (Aldrich) as a thermal radical initiator were dissolved in toluene to obtain 30 g of sample. This varnish was cast onto a film and the solvent was removed in an oven at an internal temperature of 115°C for 5 minutes. DSC analysis of the obtained B-stage film showed that the Tg of the B-stage film was 69°C. The Tg of the C-stage film after further curing at 200°C for 1 hour was 226°C. The molecular weights determined by GPC analysis were Mn = 3800 g / mol and Mw = 4900 g / mol.

[0078] [Examples 1 and 2, Comparative Examples 1 and 2] The materials listed in Table 1 were mixed in the specified proportions (parts by mass), heated, melted, and mixed in a metal container, and then poured directly into a mold. The mixture was then cured at 220°C for 2 hours. The measurement results are shown in Table 1.

[0079] M-1: A compound represented by the above formula (1), where R1 represents a methyl group, R2 represents a methyl group or a hydrogen atom, R3 represents a methyl group or a hydrogen atom, R4 to R6 represent hydrogen atoms, L, M, and N are each between 1 and 20, and O is 0. M-2: A compound represented by the above formula (1), where R1 represents a methyl group, R2 represents a methyl group or a hydrogen atom, R3 represents a methyl group or a hydrogen atom, R4 to R6 represent hydrogen atoms, and L, M, N, and O are each between 1 and 20. • SA-9000: Polyphenylene ether compound (manufactured by SABIC) • Polystyrene: Aldrich, Mw=280,000 • DCP: Dicumyl peroxide (manufactured by Nuurion Pharmaceuticals) • TOPAS 5013: Cycloolefin resin (manufactured by Polyplastics Co., Ltd.)

[0080] <Heat resistance test> • Glass transition temperature: Measured using a dynamic viscoelasticity tester, this is the temperature at which tanδ (= loss modulus of elasticity / storage modulus of elasticity) reaches its maximum value. Dynamic viscoelasticity measuring instrument: TA-instruments DMA-2980 Measurement temperature range: -30 to 280°C Heating rate: 2°C / min Frequency: 10Hz Test specimen size: A piece cut to 5mm x 50mm was used (thickness approximately 800μm). <Dielectric constant test / Dielectric loss tangent test> The test was performed using a 1GHz cavity resonator manufactured by AET Corporation, employing the cavity resonator perturbation method. The sample size was 1.7mm wide x 100mm long with a thickness of 1.7mm. Furthermore, the samples were left in a 150°C environment for 500 hours, cooled to room temperature, and then tested again using the cavity resonator perturbation method.

[0081] [Table 1]

[0082] Table 1 confirms that Examples 3 and 4 exhibit excellent heat resistance and dielectric properties. In particular, for Example 3, it was confirmed that there was almost no change in dielectric constant even after being left at 150°C for 500 hours. [Industrial applicability]

[0083] The compounds of the present invention are useful for insulating materials for electrical and electronic components (such as high-reliability semiconductor encapsulating materials) and laminates (such as printed circuit boards, BGA substrates, and build-up substrates), adhesives (such as conductive adhesives), various composite materials including CFRP, paints, and 3D printing.

Claims

1. Maleimide resin having repeating units of the following formulas (a), (b), (c), and (d). 【Chemistry 1】 (In the above formula, R １ ~R ６ represents a hydrogen atom, a hydrocarbon group with 1 to 10 carbon atoms, or a halogenated hydrocarbon group. l and m represent real numbers from 0 to 5, and n represents a real number from 0 to 4. N independently represents a real number from 1 to 20, L and M represent real numbers from 0 to 20, and O represents a real number from 1 to 20. (a), (b), (c), and (d) are each linked by *, and the repetition position can be random.

2. A maleimide resin having repeating units of the following formulas (a), (b), (c), and (d). 【Chemistry 2】 (In the above formula, R1 is a hydrocarbon group having 1 to 3 carbon atoms, and R2 to R6 represent a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, or a halogenated hydrocarbon group. l and m represent real numbers from 0 to 5, and n represents a real number from 0 to 4. N independently represents a real number from 1 to 20, L represents a real number from 1 to 20, and M and O represent real numbers from 0 to 20. (a), (b), (c), and (d) are each linked by *, and the repeating positions may be random.)

3. In the above formulas (a), (b), and (c), R １ is a methyl group, R ２ is a methyl group or a hydrogen atom, R ３ The maleimide resin according to claim 2, wherein is a methyl group or a hydrogen atom.

4. The maleimide resin according to claim 2, wherein O is 0 in formula (d) above.

5. A curable resin composition containing the maleimide resin according to any one of claims 1 to 4.

6. Furthermore, the curable resin composition according to claim 5, which further contains a curable resin other than the maleimide resin described in any one of claims 1 to 4.

7. Furthermore, the curable resin composition according to claim 5, further containing a curing accelerator.

8. A cured product obtained by curing the maleimide resin according to any one of claims 1 to 4.

9. A cured product obtained by curing the curable resin composition described in claim 5.

Images