Curable resin composition and cured product thereof

Abstract

The present invention provides a curable resin composition having high biomass, high heat resistance, and excellent low dielectric properties, and a cured product thereof. A curable resin composition has an epoxy resin represented by the following formula (1) and an anhydride hardener containing a compound derived from biomass. (In formula (1), n is an average value of the number of repetitions, and represents a real number)

Description

Technical Field

[0001] This invention relates to a curable resin composition comprising a specific epoxy resin and a specific acid anhydride, and the cured product thereof, which is suitable for use in the fields of electrical / electronic components such as semiconductor element sealants, printed wiring boards, and laminated boards, lightweight and high-strength materials such as carbon fiber reinforced plastics and glass fiber reinforced plastics, 3D printing applications, and adhesives. Background Technology

[0002] Epoxy resins are widely used in electrical / electronic components, structural materials, adhesives, and coatings due to their ease of handling and the excellent electrical properties, heat resistance, adhesion, and moisture resistance of their cured products. Furthermore, in recent years, particularly in the electrical / electronic field, there has been a growing demand for resins with improved heat resistance, low dielectric constant, and low dielectric loss tangent. Additionally, as structural materials, they are required in aerospace and recreational / sports equipment applications, where lightweight materials with excellent mechanical properties are essential.

[0003] Furthermore, from an environmental perspective, biomass resources have received considerable attention in recent years as a carbon-neutral resource. Furfural is known as a compound derived from biomass, and patent document 1 discloses an epoxy resin using furfural as a raw material.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2007-211254 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] However, Patent Document 1 produces an epoxy resin composition by mixing an epoxy resin using furfural as a raw material with a phenolic varnish resin, which is a hardener derived from petrochemicals, thus resulting in a lower biomass content in the composition.

[0009] Generally, it is difficult to maintain the required performance of curing resin compositions if the biomass content is increased. Therefore, curing resin compositions with high biomass content and meeting the required characteristics are needed.

[0010] The present invention was made in view of the above-mentioned situation, and its object is to provide a curable resin composition and its cured product with excellent high biomass content, high heat resistance, low dielectric properties.

[0011] Technical means to solve the problem

[0012] That is, the present invention relates to [1] to [9] below. In addition, in the present invention, "(numerical value 1) to (numerical value 2)" means including upper limit value and lower limit value. [1]

[0014] A curable resin composition comprising an epoxy resin represented by the following formula (1) and a biomass-modified acid anhydride.

[0015] [Chemistry 1]

[0016]

[0017] (In equation (1), n ​​is the average of the number of repetitions, representing a real number where 1 < n < 15) [2]

[0019] According to the curable resin composition described in the preceding paragraph [1], the biomass modified anhydride is selected from one or more of geraniol modified anhydride, farnesene modified anhydride, and α-terpinene modified anhydride. [3]

[0021] According to the curable resin composition described in [1] or [2] above, wherein the biomass-modified acid anhydride has a biomass content of 20% or more. [4]

[0023] The curable resin composition according to any one of the preceding items [1] to [3], wherein the ICI viscosity (150°C) of the epoxy resin is 0.01 Pa·s to 0.20 Pa·s. [5]

[0025] The curable resin composition according to any one of the preceding items [1] to [4], wherein the biomass content is 20% or more. [6]

[0027] The curable resin composition according to any one of the preceding items [1] to [5] is used for carbon fiber reinforced plastics. [7]

[0029] The curable resin composition according to any one of the preceding items [1] to [5] is used as a sealant for semiconductor devices. [8]

[0031] The curable resin composition according to any one of the preceding items [1] to [5] is used for printed wiring boards. [9]

[0033] A hardener is formed by hardening a hardening resin composition according to any one of the preceding items [1] to [8].

[0034] The effects of the invention

[0035] This invention relates to a curable resin composition with excellent high biomass content, high heat resistance, and low dielectric properties. Therefore, this invention is effectively used in insulating materials for electrical and electronic components (such as high-reliability semiconductor sealing materials) and laminates (such as printed circuit boards and add-on substrates), or in various composite materials, primarily carbon fiber reinforced plastic (CFRP), and adhesives. Attached Figure Description

[0036] Figure 1 The GPC chart represents the synthesis example 1. Detailed Implementation

[0037] The curable resin composition of this embodiment contains an epoxy resin represented by the following formula (1) and a biomass-modified acid anhydride.

[0038] [Chemistry 2]

[0039]

[0040] (In equation (1), n ​​is the average of the number of repetitions, representing a real number where 1 < n < 15)

[0041] In formula (1), the value of n can be calculated from the number average molecular weight obtained by gel permeation chromatography (GPC) of epoxy resin, detector: RI (refractive index), or the area ratio of each of the separated peaks. n is preferably a real number of 1 < n < 15, more preferably 1 < n < 10, and particularly preferably 1 < n < 5.

[0042] The epoxy resin represented by formula (1) can be obtained by reacting the phenolic resin represented by formula (2) with epihaloalcohol.

[0043] [Chemistry 3]

[0044]

[0045] (In equation (2), n is the average of the number of repetitions, representing a real number where 1 < n < 15)

[0046] The preferred range of n in equation (2) is the same as that in equation (1).

[0047] The epihalool is readily available from the market. The amount of epihalool used is preferably 2.0 to 10 moles relative to 1 mole of the hydroxyl group in the raw phenol mixture, more preferably 3.0 to 8.0 moles, and even more preferably 3.5 to 6.0 moles.

[0048] In the reaction, an alkali metal hydroxide can be used as a catalyst to promote the epoxidation process. Examples of usable alkali metal hydroxides include sodium hydroxide and potassium hydroxide. Solid components or aqueous solutions of these hydroxides can be used. In this embodiment, especially in terms of solubility and operability, it is preferable to use a solid component formed into flakes.

[0049] The amount of alkali metal hydroxide used is preferably 0.90 mol to 1.5 mol relative to 1 mol of hydroxyl groups in the phenol mixture, more preferably 0.95 mol to 1.25 mol, and even more preferably 0.99 mol to 1.15 mol.

[0050] In addition, to promote the reaction, quaternary ammonium salts such as tetramethylammonium chloride, tetramethylammonium bromide, and trimethylbenzylammonium chloride can be added as catalysts. The amount of quaternary ammonium salt used is preferably 0.1g to 15g, more preferably 0.2g to 10g, relative to 1 mole of the hydroxyl groups in the phenolic mixture.

[0051] The reaction temperature is preferably 30°C to 90°C, more preferably 35°C to 80°C. Particularly in this embodiment, to achieve higher purity epoxidation, a temperature of 50°C or higher is preferred, and particularly preferably 60°C or higher. The reaction time is preferably 0.5 hours to 10 hours, more preferably 1 hour to 8 hours, and particularly preferably 1 hour to 3 hours. A short reaction time will prevent the reaction from proceeding completely, while a long reaction time will produce byproducts, which is therefore undesirable.

[0052] The reaction products of these epoxidation reactions are removed by washing with water, or by heating under reduced pressure without washing, to remove the surface halohydrins or solvents. Alternatively, to produce epoxy resins with fewer hydrolyzable halogens, ketone compounds with 4 to 7 carbon atoms (e.g., methyl isobutyl ketone, methyl ethyl ketone, cyclopentanone, cyclohexanone, etc.) can be used as solvents to dissolve the recovered epoxy resin, and aqueous solutions of alkali metal hydroxides such as sodium hydroxide or potassium hydroxide are added to carry out the reaction, ensuring reliable ring closure. In this case, the amount of alkali metal hydroxide used is preferably 0.01 to 0.3 mol, more preferably 0.05 to 0.2 mol, relative to 1 mol of hydroxyl groups in the phenol mixture used in the epoxidation. The reaction temperature is preferably 50°C to 120°C, and the reaction time is preferably 0.5 to 2 hours.

[0053] After the reaction is complete, the generated salt is removed by filtration and washing with water, and then the solvent is removed by distillation under heating and reduced pressure, thereby obtaining the epoxy resin represented by formula (1).

[0054] As a method for synthesizing the phenolic resin represented by formula (2), when the reaction (condensation) of furfural and phenol is carried out, the amount of phenol is preferably in the range of 1.5 mol to 20 mol relative to 1 mol of furfural, and particularly preferably in the range of 3 mol to 10 mol.

[0055] Regarding phenols, examples of disubstituted phenols include catechol, resorcinol, and hydroquinone, while examples of monosubstituted phenols include phenol. They can be used alone or in combination with two or more.

[0056] Examples of solvents include methanol, ethanol, propanol, isopropanol, toluene, and xylene, but these are not limited to. A solvent can be used alone or in combination with two or more solvents. When using a solvent, the amount used is preferably in the range of 5 to 500 parts by weight relative to 100 parts by weight of phenol, and more preferably in the range of 10 to 300 parts by weight.

[0057] In the condensation reaction, an alkaline catalyst is preferred. While acidic catalysts can also be used for condensation, furfural reacts with itself, resulting in more byproducts. Alternatively, organometallic compounds can be used, but this is less costly. Specific examples of alkaline catalysts include alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, and potassium hydroxide; alkaline earth metal hydroxides such as magnesium hydroxide and calcium hydroxide; alkali metal alkoxides such as sodium methoxide, sodium ethoxide, potassium methoxide, potassium ethoxide, and potassium tert-butoxide; and alkaline earth metal alkoxides such as magnesium methoxide and magnesium ethoxide, but these are not limited to these; two or more catalysts can be used alone or in combination. The amount of catalyst used relative to 1 mole of phenol is preferably 0.005 to 2.0 moles, more preferably 0.01 to 1.1 moles.

[0058] The condensation reaction in the presence of these alkaline catalysts is preferably carried out in the range of 40°C to 180°C, particularly preferably in the range of 80°C to 165°C, and the reaction time is preferably selected in the range of 0.5 hours to 10 hours. The reaction product thus obtained is neutralized or repeatedly washed with water in the presence of a solvent to make the system neutral, the water is separated and drained, and the solvent and unreacted substances are removed under heating and reduced pressure, thereby obtaining the phenolic resin represented by formula (2).

[0059] The curable resin composition of this embodiment also contains the epoxy resin represented by formula (1) and biomass-modified acid anhydride. Biomass-modified acid anhydride refers to anhydride modified using biomass raw materials, such as geraniol-modified acid anhydride, farnesene-modified acid anhydride, and α-terpinene-modified acid anhydride. These can be obtained by reacting terpenoid compounds such as geraniol, farnesene, and α-terpinene with anhydrides such as maleic anhydride, itaconic anhydride, and citraconic anhydride. Furthermore, the curable resin composition of this embodiment may also incorporate anhydrides other than biomass-modified acid anhydride, such as phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, hexahydrophthalic anhydride, and methylhexahydrophthalic anhydride. These can be used in any proportion, but if the proportion of biomass-modified anhydride in the total amount of anhydride used is 30% to 100% by weight, the biomass content can be improved, and therefore this is preferred. The anhydride is preferably 0.7 to 1.2 equivalents relative to the epoxy group equivalent of the epoxy resin represented by formula (1). If the amount is less than 0.7 equivalents relative to the epoxy group equivalent, or exceeds 1.2 equivalents, curing becomes incomplete, and there is a possibility that good cured properties cannot be obtained.

[0060] From an environmental perspective, the biomass content of the epoxy resin represented by formula (1) is preferably 20% or more. The biomass content of the biomass-modified anhydride is preferably 20% or more, more preferably 40% or more, and particularly preferably 60% or more. The biomass content of the curing resin composition of this embodiment is preferably 20% or more, more preferably 30% or more, and particularly preferably 40% or more. There is no particular upper limit to the biomass content, and it can be 100%, but for the balance with the curing properties, 60% is preferred. A high biomass content can also reduce the amount of fossil resource materials such as petroleum, and therefore is also significant in terms of the sustainable use of resources.

[0061] The biomass of each material or curing resin composition can be determined by accelerator gravimetric analysis according to American Society for Testing and Materials (ASTM) D6866-21.

[0062] In the curable resin composition of this embodiment, the epoxy resin represented by formula (1) can be used alone or in combination with other epoxy resins. When used in combination, the epoxy resin represented by formula (1) preferably accounts for 5% to 95% by weight of all epoxy resins, more preferably 10% to 95% by weight, and even more preferably 15% to 95% by weight. When the amount added is small, sufficient heat resistance may not be observed.

[0063] Specific examples of epoxy resins that can be used in conjunction with the epoxy resin represented by formula (1) include: condensation products of bisphenols (bisphenol A, bisphenol F, bisphenol S, biphenol, bisphenol AD, etc.) or phenols (phenol, alkyl-substituted phenols, aromatic-substituted phenols, naphthol, alkyl-substituted naphthols, dihydroxybenzene, alkyl-substituted dihydroxybenzene, dihydroxynaphthalene, etc.) with various aldehydes (formaldehyde, acetaldehyde, alkyl aldehydes, benzaldehyde, alkyl-substituted benzaldehyde, hydroxybenzene, naphthal, glutaraldehyde, o-phthalaldehyde, crotonaldehyde, cinnamaldehyde, etc.); and condensation products of the phenols with various diene compounds (dicyclopentadiene, terpenes, vinylcyclohexene, norbornene, vinylnorbornene, tetrahydroindene, divinylbenzene, divinylbiphenyl, diisopropenylbiphenyl). Polymers of phenols and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone, benzophenone, etc.); condensation polymers of phenols and aromatic dimethyl alcohols (benzenedimethanol, biphenyl dimethylethanol, etc.); condensation polymers of phenols and aromatic dichloromethyl alcohols (α,α'-dichloroxylene, dichloromethylbiphenyl, etc.); condensation polymers of phenols and aromatic diekoxymethyl alcohols (dimethoxymethylbenzene, dimethoxymethylbiphenyl, diphenoxymethylbiphenyl, etc.); condensation polymers of bisphenols and various aldehydes, or glycidyl ether epoxy resins, alicyclic epoxy resins, glycidyl amine epoxy resins, glycidyl ester epoxy resins, etc., obtained by glycidylating alcohols, etc. Specific examples of epoxy resins containing plant-derived components include compounds formed by epoxidizing a condensation polymer of cashew nut oil (a type of phenol) with various aldehydes, or compounds formed by epoxidizing linseed oil or soybean oil. These are not limited to any commonly used epoxy resin. These can be used alone or in combination with other epoxy resins. In particular, using them in combination with epoxy resins containing plant-derived components can improve biomass content, which is preferred.

[0064] The curable resin composition of this embodiment may also be used in conjunction with curing agents other than acid anhydrides. Examples include amine compounds, amide compounds, phenolic compounds, and reactive ester compounds. Specific examples of curing agents that can be used in conjunction include: dicyandiamine, polyamide resins synthesized from dimers of linoleic acid and ethylenediamine, and other amide compounds; o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 4,4'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 2,2'-diaminodiphenyl sulfone, diethyltoluenediamine, dimethylthiotoluenediamine, diaminodiphenylmethane, 3,3'-dimethyl... 4,4'-Diaminodiphenylmethane, 3,3'-Diethyl-4,4'-Diaminodiphenylmethane, 4,4'-Diamino-3,3'-Diethyl-5,5'-Dimethyldiphenylmethane, 4,4'-Diamino-3,3',5,5'-Tetramethyldiphenylmethane, 4,4'-Diamino-3,3',5,5'-Tetramethyldiphenylmethane, 4,4'-Diamino-3,3',5,5'-Tetraisopropyldiphenylmethane, 4,4'-Methylenebis(N-methylaniline), bis(aminophenyl)fluorene, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 2,2'-bis[4-(4-aminophenoxy)phenyl]propane, bis[4-(4-aminophenoxy)phenyl]sulfone, 1,3'-bis(4-aminophenoxy)benzene, 1,4'-bis(4-aminophenoxy)benzene, 1,4'-bis(4-aminophenoxy)biphenyl, 4,4'-(1, Aromatic amine compounds such as 3-phenylene diisopropylidene (PDI)-bisaniline, 4,4'-(1,4-phenylene diisopropylidene)-bisaniline, naphthyldiamine, benzidine, and dimethylbenzidine; and aliphatic amine compounds such as 1,3-bis(aminomethyl)cyclohexane, isophorone diamine, 4,4'-methylenebis(cyclohexylamine), norbornene diamine, ethylenediamine, propylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, dimerized diamine, and triethylenetetramine.Polymers of bisphenols (bisphenol A, bisphenol F, bisphenol S, biphenol, bisphenol AD, etc.) or phenols (phenol, alkyl-substituted phenols, aromatic-substituted phenols, naphthol, alkyl-substituted naphthols, dihydroxybenzene, alkyl-substituted dihydroxybenzene, dihydroxynaphthalene, etc.) with various aldehydes (formaldehyde, acetaldehyde, alkyl aldehydes, benzaldehyde, alkyl-substituted benzaldehyde, hydroxybenzene, naphthal, glutaraldehyde, o-phthalaldehyde, crotonaldehyde, cinnamaldehyde, etc.), or polymers of the aforementioned phenols with various diene compounds (dicyclopentadiene, terpenes, vinylcyclohexene, norbornene, vinylnorbornene, tetrahydroindene, divinylbenzene, divinylbiphenyl, diisopropenylbiphenyl, butadiene, isoprene, etc.), or polymers of the aforementioned phenols with ketones. Phenolic compounds include condensation polymers of acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone, benzophenone, etc.; condensation polymers of phenols with aromatic dimethyl alcohols (benzenedimethanol, biphenyl dimethyl alcohol, etc.); condensation polymers of phenols with aromatic dichloromethyl alcohols (α,α'-dichloroxylene, dichloromethylbiphenyl, etc.); condensation polymers of phenols with aromatic diekoxymethyl alcohols (dimethoxymethylbenzene, dimethoxymethylbiphenyl, diphenoxymethylbiphenyl, etc.); condensation polymers of bisphenols with various aldehydes; and modified forms thereof; phenolic compounds; phenolic esters, thiophenolic esters, N-hydroxyamine esters, esters of heterocyclic hydroxyl compounds, and other active ester compounds, but are not limited to these.

[0065] The curable resin composition of this embodiment may also be used in conjunction with a curing accelerator. Examples of usable curing accelerators include: imidazoles such as 2-methylimidazole, 2-ethylimidazole, 2-phenylimidazole, and 2-ethyl-4-methylimidazole; organophosphorus compounds such as triphenylphosphine, diphenylphosphine, and tributylphosphine; metal compounds such as tin octoate; tetrasubstituted phosphine-tetrasubstituted borates such as tetraphenylphosphine-tetraphenylboronic acid ester and tetraphenylphosphine-ethyltriphenylboronic acid ester; tetraphenylborates such as 2-ethyl-4-methylimidazole-tetraphenylboronic acid ester and N-methylmorpholine-tetraphenylboronic acid ester; benzoic acid esters; phthalic acid; isophthalic acid; terephthalic acid; naphtholic acid; and carboxylic acid compounds such as salicylic acid. For every 100 parts by weight of epoxy resin, use 0.01 to 15 parts by weight of curing accelerator as needed.

[0066] The curable resin composition of this embodiment may be supplemented with inorganic fillers as needed. Examples of inorganic fillers include powders of crystalline silica, fused silica, alumina, zircon, calcium silicate, calcium carbonate, silicon carbide, silicon nitride, boron nitride, zirconium oxide, forsterite, steatite, spinel, titanium dioxide, talc, etc., or spheroidized beads, but are not limited to these. These fillers may be used alone or in combination. The amount of these inorganic fillers used varies depending on the application, but for example, in the case of a sealant for semiconductor components, it is preferable to use them at a proportion of 20% by weight or more, more preferably 30% by weight or more, in order to improve the heat resistance, moisture resistance, mechanical properties, and flame retardancy of the cured resin composition. In particular, it is more preferable to use them at a proportion of 70% to 95% by weight to improve the linear expansion rate relative to the lead frame.

[0067] In the curable resin composition of this embodiment, a release agent can be formulated to ensure good demolding from the mold during molding. Any known release agent can be used, such as: ester waxes like carnauba wax and montan wax; fatty acids like stearic acid and palmitic acid, and their metal salts; polyolefin waxes like oxidized polyethylene and non-oxidized polyethylene. These can be used alone or in combination of two or more. The amount of these release agents is preferably 0.5% to 3% by weight relative to all organic components. If this amount is too small, demolding from the mold will be poor; if this amount is too large, adhesion to the lead frame, etc., will be poor.

[0068] In the curable resin composition of this embodiment, a coupling agent can be adjusted to improve the adhesion between the inorganic filler and the resin components. Any known coupling agent can be used, such as: vinylalkoxysilanes, epoxyalkoxysilanes, styrylalkoxysilanes, methacryloxyalkoxysilanes, acryloxyalkoxysilanes, aminoalkoxysilanes, mercaptoalkoxysilanes, isocyanoalkoxysilanes, and various alkoxysilane compounds, alkoxytitanium compounds, aluminum chelates, etc. These can be used alone or in combination of two or more. Regarding the method of adding the coupling agent, the inorganic filler surface can be pre-treated with the coupling agent and then mixed with the resin, or the coupling agent can be mixed into the resin first and then the inorganic filler can be mixed.

[0069] In the curable resin composition of this embodiment, known additives may be formulated as needed. Specific examples of additives that can be used include: polybutadiene and its modified forms, modified acrylonitrile copolymers, polyphenylene ether, polystyrene, polyethylene, polyimide, fluororesin, maleimide compounds, cyanate ester compounds, silicone gels, silicone oils, and colorants such as carbon black, phthalocyanine blue, and phthalocyanine green.

[0070] The curable resin composition of this embodiment is obtained by uniformly mixing the aforementioned components. The method for manufacturing the curable resin composition of this embodiment is not particularly limited; for example, it can be obtained by thoroughly mixing the curing agent, curing accelerator, inorganic filler, release agent, silane coupling agent, additives, etc., into the epoxy resin until they become homogeneous using an extruder, kneader, roller, planetary mixer, etc.

[0071] The obtained curable resin composition can be in various forms, such as resin sheets or prepregs, through its molding method. For example, a prepreg can be obtained by heating and melting the curable resin composition and / or resin sheets of this embodiment to reduce their viscosity and then impregnating them in a fiber substrate.

[0072] The curable resin composition of this embodiment can also be dissolved in solvents such as toluene, xylene, acetone, methyl ethyl ketone, methyl isobutyl ketone, dimethylformamide, dimethylacetamide, and N-methylpyrrolidone to prepare a varnish-like composition (hereinafter also simply referred to as varnish), which is then impregnated in substrates such as glass fiber, carbon fiber, polyester fiber, polyamide fiber, alumina fiber, and paper, and dried by heating to produce a prepreg. In this case, the solvent used is in an amount of 10% to 70% by weight, preferably 15% to 70% by weight, in the mixture of the curable resin composition of this embodiment and the solvent.

[0073] After the prepreg is cut into the desired shape and stacked, pressure is applied to the stack using methods such as compression molding, autoclave molding, or sheet winding, while the epoxy resin composition is heated and hardened, thereby obtaining carbon fiber reinforced plastic (CFRP). Alternatively, copper foil or organic film can be stacked during the stacking of the prepreg.

[0074] Regarding the molding method of CFRP, in addition to the method described above, it can also be obtained by using known methods. For example, the following resin transfer molding (RTM) method can also be used: a preform (a preform before resin impregnation) is made by cutting, stacking, and shaping a carbon fiber substrate (usually carbon fiber fabric), the preform is placed in a molding mold and the mold is closed, resin is injected to impregnate the preform and harden it, and then the mold is opened and the molded article is removed. Alternatively, methods such as Vacuum Assisted Resin Transfer Molding (VaRTM), Seeman's Composite Resin Infusion Molding Process (SCRIMP), and Controlled Atmospheric Pressure Resin Infusion (CAPRI) as described in Japanese Patent Publication No. 2005-527410 can be used. CAPRI involves venting the resin supply tank until the pressure drops below atmospheric pressure, using cyclic compression, and controlling the net forming pressure, thereby more appropriately controlling the resin injection process, particularly the VaRTM method. Furthermore, methods such as film stacking (using resin sheets / films to sandwich fiber substrates) can also be used; methods to adhere powdered resin to reinforced fiber substrates to improve impregnation; forming methods using flow layers or fluid slurry methods (powder impregnated yarn) during resin mixing in fiber substrates; and methods to weave resin fibers into fiber substrates.

[0075] Examples of carbon fibers include acrylic, pitch, and rayon fibers, among which acrylic fibers with high tensile strength are preferred. As for the form of carbon fibers, twisted yarn, untwisted yarn, and untwisted yarn can be used, but to achieve a good balance between the formability and strength properties of the fiber-reinforced composite material, untwisted yarn or untwisted yarn is preferred.

[0076] The cured resin composition of this embodiment can be used for various purposes in addition to the aforementioned CFRP and other applications. Examples include: adhesives, coatings, coating agents, molding materials (including sheets, films, CFRP, etc.), sealants for semiconductor elements, sealants for liquid crystal display elements, sealants for organic electroluminescence (EL) elements, electrical / electronic parts such as printed wiring boards (ball grid array (BGA) substrates, build-up substrates, etc.) or three-dimensional (3D) printing, and additives to other resins, etc.

[0077] Examples of such adhesives include those used in civil engineering, construction, automotive, general office, and medical applications, as well as adhesives for electronic materials. Among these, adhesives for electronic materials include interlayer adhesives, die bonding agents, underfills, and other semiconductor adhesives for multilayer substrates such as uplayer substrates; underfills for BGA reinforcement, anisotropic conductive films (ACF), anisotropic conductive pastes (ACP), and other mounting adhesives, which can be used in various applications.

[0078] When the curable resin composition of this embodiment is applied to a sealing material for semiconductor devices, a lead frame including a semiconductor device and a semiconductor packaging substrate are placed in a mold, and the curable resin composition of this embodiment is formed by melt injection molding, transfer molding, injection molding, compression molding, etc., and then heated at 80°C to 200°C for 2 to 10 hours to obtain a cured product. Examples of sealing methods for semiconductor devices using this sealing material include: potting seals, impregnation seals, and transfer mold seals for capacitors, transistors, diodes, light-emitting diodes, integrated circuits (ICs), large-scale integrated circuits (LSIs), etc.; potting seals for ICs and LSIs such as chip-on-board (COB), chip-on-film (COF), and tape-automated bonding (TAB); underfills for flip-chip devices; and seals (including reinforcing underfills) during IC package mounting such as quad flat packages (QFPs), ball grid arrays (BGAs), and chip-scale packages (CSPs).

[0079] When applying the curable resin composition of this embodiment to printed wiring boards, a prepreg can be obtained by heating and melting it to reduce its viscosity and then impregnating it with reinforcing fibers such as glass fibers and polyamide fibers. Specific examples include glass fibers and / or organic 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, but these are not particularly limited. The shape of the substrate is not particularly limited; examples include woven fabric, non-woven fabric, roving, and woven felt. Furthermore, known weaving methods include plain weave, satin weave, and twill weave; these known weaving methods can be selected according to the target application or performance suitability. Additionally, woven fabrics that have undergone fiber opening treatment or glass fabrics that have undergone surface treatment using silane coupling agents are suitable. The thickness of the substrate is not particularly limited, but is preferably around 0.01 mm to 0.4 mm. Alternatively, a prepreg can be obtained by impregnating the varnish in reinforcing fibers and then heating and drying it, based on which a copper clad laminate (CCL) can be manufactured. A laminate using the curable resin composition of this embodiment can also be manufactured by hot-pressing the obtained prepreg with a CCL. The laminate is not particularly limited as long as it includes one or more prepregs, and may have any other layers. Furthermore, by coating the varnish onto a release film, removing the solvent under heating, and performing a B-stage process, a sheet-like adhesive can be obtained. This sheet-like adhesive can be used as an interlayer insulating layer in multilayer substrates or as an adhesive sheet when mounting semiconductors. Additionally, the curable resin composition of this embodiment can also be suitably used for special substrate materials such as encapsulation substrates (substrates) or high-density interconnects (HDI).

[0080] Example

[0081] The following examples and embodiments illustrate the invention in more detail. The materials, processing methods, and procedures described below may be appropriately modified without departing from the spirit of the invention. Therefore, the scope of the invention should not be limited by the specific examples shown below. Unless otherwise specified, parts are parts by weight.

[0082] The various analytical methods are performed under the following conditions.

[0083] · Epoxy equivalent

[0084] The determination was performed using the method described in Japanese Industrial Standards (JIS) K-7236, and the unit is g / eq.

[0085] · Softening point

[0086] The measurements were performed according to the method in JIS K-7234, and the units are in °C.

[0087] Melt viscosity

[0088] The melt viscosity was determined using the ICI cone-plate method (150°C), and the unit is Pa·s.

[0089] • Biomass gravimetric analysis (accelerator gravimetric analysis)

[0090] Measured and calculated according to ASTM D6866-21. Units are percentages.

[0091] [Synthesis example 1]

[0092] 254 parts by weight of phenol, 63 parts by weight of water, and 27 parts by weight of sodium hydroxide were added to a flask containing a stirrer, reflux cooling tube, and stirring device. After stirring and dissolving, the mixture was heated to 110°C, and 44 parts by weight of furfural were added dropwise over 2 hours. The reaction was then carried out at 110°C for 3 hours, followed by a temperature increase to 145°C. During the temperature increase, the distilled water was removed from the system. After reaching 145°C, the reaction was continued for 4 hours. Subsequently, the mixture was cooled to 80°C, and 63 parts by weight of water were added, along with 4 parts by weight of phosphoric acid and 63 parts by weight of 35% hydrochloric acid for neutralization. After repeated washing with water, unreacted phenol was removed by distillation under heating and reduced pressure, yielding 109 parts by weight of phenol resin. To the extent that 78 parts by weight of the obtained phenolic resin were obtained, 254 parts by weight of epichlorohydrin (ECH, hereinafter the same), 64 parts by weight of dimethyl sulfoxide (DMSO, hereinafter the same), and 13 parts by weight of water were added to a reaction vessel. After heating, stirring, and dissolving, 23 parts by weight of flake sodium hydroxide were added in portions over a period of 2 hours while maintaining the temperature at 45°C. The reaction was then carried out for another 2 hours at 45°C and then for another 60 minutes at 70°C. The mixture was then repeatedly washed with water to remove byproduct salts and DMSO. Excess epichlorohydrin was removed by distillation from the oil layer under reduced pressure. 218 parts by weight of methyl isobutyl ketone were added to the residue for dissolution. The methyl isobutyl ketone solution was heated to 70°C, and 7 parts by weight of a 30% sodium hydroxide aqueous solution were added. After reacting for 1 hour, the reaction solution was repeatedly washed with water until the washing solution became neutral. Subsequently, methyl isobutyl ketone was removed from the oil layer by distillation under heating and reduced pressure, thereby obtaining 97 parts by weight of epoxy resin A represented by formula (1). The epoxy equivalent was 214 g / eq, the softening point was 49 °C, the ICI melt viscosity was 0.04 Pa·s, the average number of replicates obtained from GPC was 2.1, and the biomass content was 25%. The GPC diagram of epoxy resin A is shown in [the diagram]. Figure 1 .

[0093] [Synthesis example 2]

[0094] In a four-necked flask, 49.1 g of toluene and 25.8 parts of α-terpinene (manufactured by Guangxi Jiexin Fragrance Co., Ltd.) were placed and heated to 85°C with stirring. 16.7 parts of maleic anhydride were divided into four portions and added to the solution over a period of 1 hour. After the addition was complete, the mixture was stirred at 85°C for 1 hour. After the reaction was complete, the mixture was concentrated under reduced pressure at 185°C to obtain 37 parts of anhydride A.

[0095] [Example 1]

[0096] Using epoxy resin A obtained in Synthesis Example 1 as the main agent, acid anhydride A obtained in Synthesis Example 2 as a hardener and 2E4MZ (2-ethyl-4-methylimidazole) (manufactured by Shikoku Kasei Corporation) as an anionic polymerization initiator were mixed and kneaded according to the weight ratio shown in Table 1. The mixture was then cured at 160°C for 6 hours to produce a cured product. The biomass content of the cured product was 48.6%.

[0097] [Comparative Example 1]

[0098] Using epoxy resin A obtained in Synthesis Example 1 as the main agent, Kayahard MCD (methylnadic anhydride, manufactured by Nippon Kayaku Co., Ltd.) as a curing agent and 2E4MZ (2-ethyl-4-methylimidazolium, manufactured by Shikoku Kasei Co., Ltd.) as an anionic polymerization initiator were mixed and kneaded according to the weight ratio shown in Table 1. The mixture was then cured at 160°C for 6 hours to produce a cured product. The biomass content of the cured product was 15.2%.

[0099] [Comparative Example 2]

[0100] Using epoxy resin A obtained in Synthesis Example 1 as the main agent, PN (phenolnovolac) (phenolic varnish resin, manufactured by Meiwa Chemical Co., Ltd., hydroxyl equivalent 103 g / eq.) as a curing agent and triphenylphosphine (TPP) as a curing accelerator were mixed and kneaded according to the weight ratio shown in Table 1. The mixture was then cured at 180°C for 6 hours to produce a cured product. The biomass content of the cured product was 16.6%.

[0101] The determination of physical properties shall be carried out under the following conditions.

[0102] <Determination conditions for heat resistance (Tg)>

[0103] Dynamic viscoelasticity measuring instrument: TA-instruments, DMA-Q800

[0104] Measurement temperature range: 25℃~300℃

[0105] Heating rate: 2℃ / minute

[0106] Tg: Set the peak point of Tanδ to Tg.

[0107] <Dielectric constant and dielectric loss tangent test>

[0108] A 10GHz cavity resonator manufactured by AET Corporation was used for testing at 25°C using the cavity resonator perturbation method. The sample size was set to 2.5mm in width × 50mm in length and 0.3mm in thickness.

[0109] [Table 1]

[0110] Epoxy Resin A 48 57 68 2E4MZ 1 1 - Acid anhydride A 52 - - Kayahard MCD - 43 - PN - - 32 TPP - - 1 Evaluation results Tg (°C) 208 207 145 Dielectric constant 2.57 2.73 3 Dielectric loss tangent 0.012 0.016 0.033 Biomass content (%) 48.6 15.2 16.6

[0111] Based on the results in Table 1, it was confirmed that the biomass of Example 1 has excellent properties such as high biomass density, high heat resistance, and low dielectric properties.

Claims

1. A curable resin composition comprising an epoxy resin represented by formula (1) and a biomass-modified acid anhydride, The biomass-modified acid anhydride is selected from one or more of geraniol-modified acid anhydride, farnesene-modified acid anhydride, and α-terpinene-modified acid anhydride. In equation (1), n ​​is the average of the number of repetitions, representing The real number.

2. The curable resin composition according to claim 1, wherein, The biomass-modified acid anhydride has a biomass content of 20% or higher.

3. The curable resin composition according to claim 1, wherein, The ICI viscosity (150°C) of the epoxy resin is: .

4. The curable resin composition according to claim 1, wherein, The biomass content is above 20%.

5. Use of the curable resin composition according to any one of claims 1 to 4 for carbon fiber reinforced plastics.

6. Use of the curable resin composition according to any one of claims 1 to 4 for use as a sealant for semiconductor devices.

7. Use of the curable resin composition according to any one of claims 1 to 4 for printed wiring boards.

8. A hardened material, which is formed by hardening a hardening resin composition as described in any one of claims 1 to 4.

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