Epoxy resin production method, epoxy resin composition, cured product, and electric / electronic component

Abstract

A method for producing an epoxy resin by reacting epihalohydrin with a raw material phenol compound or with a raw material amine compound, said method being characterized in that the reaction is carried out in the presence of a compound represented by formula (1). (In formula (1), R1 represents an aliphatic hydrocarbon group having 1-8 carbon atoms.)

Description

Epoxy resin manufacturing method, epoxy resin composition, cured product, and electric / electronic parts

[0001] The present invention relates to a method for producing an epoxy resin, and more specifically to an industrially advantageous method for producing an epoxy resin, an epoxy resin or an epoxy resin composition obtained by the method, a cured product obtained by curing the epoxy resin composition, and an electric / electronic part.

[0002] Epoxy resins, when cured with various curing agents, generally produce cured products with excellent mechanical properties, heat resistance, electrical properties, etc., and are therefore used in a wide range of fields, including adhesives, paints, and electrical and electronic materials. In particular, within the field of electrical and electronic materials, tetramethylbiphenol-type epoxy resins are widely used in semiconductor encapsulation applications, as they can provide encapsulants with high added value.

[0003] Recent trends in semiconductor encapsulant manufacturing technology require the following (1), (2), and (3): (1) Cost reduction through streamlining of the semiconductor encapsulant manufacturing process. Not only are improvements in the quality of the epoxy resin raw material and the productivity of the manufacturing process required, but there is also a need for streamlining of the quality of the cured product itself and the curing process when mixing the epoxy resin with a curing agent to obtain a cured product such as a semiconductor encapsulant. (2) Adaptation to semiconductor manufacturing in high-temperature environments. For epoxy resins used as raw materials for semiconductor encapsulants, the cured product obtained by mixing them with a curing agent and curing them must have excellent heat resistance and durability, assuming manufacturing in high-temperature environments. (3) High reliability of semiconductor encapsulants for long-term use. For epoxy resins used as raw materials for semiconductor encapsulants, the cured product obtained by mixing them with a curing agent and curing them must have excellent electrical reliability, assuming long-term use.

[0004] Patent Document 1 describes the production of a tetramethylbiphenol-type epoxy resin by reacting 4,4'-bishydroxy-3,3',5,5'-tetramethylbiphenyl with epichlorohydrin.

[0005] Japanese Patent Application Publication No. 58-039677

[0006] Traditionally, semiconductors have been manufactured using high-temperature molding processes that enable short production times to improve productivity. However, in recent years, efforts have been made to develop semiconductor manufacturing processes that allow molding at lower temperatures in order to reduce environmental impact. However, some manufacturing processes, such as reflow molding, require high-temperature molding due to the characteristics of the materials. However, thermal cracking caused by water absorption during molding at high temperatures has become an issue. This trend in semiconductor manufacturing processes has led to a demand for semiconductor materials that can be molded at lower temperatures and have high heat resistance and durability during molding. For semiconductor encapsulation materials, there is a need for low-water absorption materials that flow at lower temperatures and are highly durable against high-temperature manufacturing processes. Furthermore, semiconductors are increasingly required to have high electrical reliability that can withstand long-term use, with the aim of improving the safety of autonomous driving technology and extending the lifespan of electronic devices. This semiconductor technology trend has led to a demand for semiconductor materials with lower water absorption and higher electrical reliability, leading to a demand for low-water absorption materials for semiconductor encapsulation materials that can be expected to have higher electrical reliability over long-term use.

[0007] The epoxy resin described in Patent Document 1 was not fully satisfactory in terms of the speed of melt mixing of the epoxy resin with other components, which is essential for productivity, in a manufacturing process for a semiconductor encapsulant in which the epoxy resin is produced on an industrial scale and then cured using the epoxy resin. Furthermore, when the cured product obtained using the epoxy resin described in Patent Document 1 was manufactured as a semiconductor encapsulant at high temperatures, cracks sometimes occurred in the encapsulant, and the heat resistance durability at high temperatures was not satisfactory. Furthermore, when the cured product obtained using the epoxy resin described in Patent Document 1 was used as a semiconductor encapsulant for a long period of time, water absorption by the encapsulant sometimes caused electrical problems such as wiring corrosion, and the electrical reliability was not satisfactory.

[0008] Therefore, an object of the present invention is to provide an epoxy resin composition which has high productivity during epoxy resin production, flows at lower temperatures during semiconductor production, has excellent industrial handleability, is highly resistant to high-temperature molding processes, and has low water absorption and high electrical reliability as a semiconductor encapsulant; a method for producing the same; and a cured product and an electrical / electronic device made from the same.

[0009] As a result of intensive investigations to solve the above-mentioned problems, the present inventors have found that the above-mentioned problems can be solved by making a compound having a specific ether structure present when an epoxy resin is produced by reacting a raw material phenol compound or amine compound with an epihalohydrin, and the resulting epoxy resin thus obtained has thus completed the present invention.

[0010] That is, the gist of the present invention lies in the following [1] to

[10] .

[0011] [1] A method for producing an epoxy resin by reacting a starting phenol compound or a starting amine compound with epihalohydrin, characterized in that the reaction is carried out in the presence of a compound represented by the following formula (1):

[0012]

[0013] (In the above formula (1), R １ represents an aliphatic hydrocarbon group having 2 to 8 carbon atoms.

[0014] [2] The method for producing an epoxy resin according to [1], wherein the amount of the compound represented by formula (1) is 0.01 to 19% by mass relative to the epihalohydrin.

[0015] [3] The method for producing an epoxy resin according to [1] or [2], wherein the raw material phenol compound is represented by the following formula (2), and the epoxy resin contains an epoxy compound represented by the following formula (3):

[0016]

[0017] (In the above formulas (2) and (3), X １ represents a divalent hydrocarbon group having 1 to 13 carbon atoms, -O-, -S-, -SO ２ -, -C(CF ３ ) ２- and -CO- or a direct bond, and R ２ ~R １３ are each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or an alkynyl group having 2 to 12 carbon atoms; and n represents an integer of 0 to 10.

[0018] [4] The method for producing an epoxy resin according to any one of [1] to [3], wherein the epoxy resin contains an epoxy compound represented by the following formula (4):

[0019]

[0020] (In the above formula (4), X １ , R ２ ~R １３ , n has the same meaning as in formula (2) and formula (3), R １ has the same meaning as in formula (1).

[0021] [5] An epoxy resin composition (A) containing 80.0 to 99.9 mass% of an epoxy compound represented by the following formula (3) and 0.1 to 8.0 mass% of an epoxy compound represented by the following formula (5):

[0022]

[0023] (In the above formulas (3) and (5), X １ represents a divalent hydrocarbon group having 1 to 13 carbon atoms, -O-, -S-, -SO ２ -, -C(CF ３ ) ２ - and -CO- or a direct bond, and R ２ ~R １３ are each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or an alkynyl group having 2 to 12 carbon atoms. n represents an integer of 0 to 10. R １４ is a non-linear aliphatic hydrocarbon group having 3 to 8 carbon atoms.

[0024] [6] The epoxy resin composition (A) according to [5], wherein the amount of hydrolyzable chlorine is 1000 ppm by mass or less.

[0025] [7] An epoxy resin composition (B) comprising the epoxy resin composition (A) according to [5] or [6], and containing 0.01 to 1,000 parts by mass of a curing agent per 100 parts by mass of the epoxy resin composition (A).

[0026] [8] The epoxy resin composition (B) according to [7], wherein the curing agent is at least one selected from the group consisting of a phenol-based curing agent, an amine-based curing agent, an acid anhydride-based curing agent, and an amide-based curing agent.

[0027] [9] A cured product obtained by curing the epoxy resin composition (B) according to [7] or [8].

[0028]

[10] An electric or electronic part obtained by curing the epoxy resin composition (B) according to [7] or [8].

[0029] The epoxy resin obtained by the present invention has a low melting point and excellent fluidity at low temperatures, and is therefore expected to flow at lower temperatures during semiconductor manufacturing, improving industrial handleability in the semiconductor manufacturing process. Furthermore, the epoxy resin obtained by the epoxy resin manufacturing method of the present invention and / or the cured product using the epoxy resin composition of the present invention has low water absorption and a low chlorine content, and therefore has excellent long-term electrical reliability, as well as low water absorption, excellent heat resistance and durability in the high-temperature environment used in semiconductor manufacturing, and a low elastic modulus that can relieve stress due to temperature changes, making it suitable for use as a semiconductor encapsulation material, etc.

[0030] An embodiment of the present invention will be described in detail below. The following description is an example of an embodiment of the present invention, and the present invention is not limited to the following description as long as it does not deviate from the gist of the present invention. In this specification, when the expression "to" is used, it is used as an expression including the numerical values ​​or physical property values ​​before and after it. The epoxy resin of this embodiment may be one having a repeating structure or one having a monomolecular structure, but in the industry, both epoxy compounds may be expressed and sold as "epoxy resin" or "epoxy resin composition." In addition, in the industry, a mixture further containing an epoxy resin different from the epoxy resin of this embodiment may be expressed as an "epoxy resin composition," or may simply be referred to as "epoxy resin."

[0031] [Method for producing epoxy resin] The method for producing an epoxy resin according to the first embodiment of the present invention is characterized in that, when a starting material phenol compound or a starting material amine compound is reacted with an epihalohydrin to produce an epoxy resin, the reaction is carried out in the presence of a compound represented by the following formula (1) (hereinafter, sometimes referred to as "compound (1)").

[0032]

[0033] (In the above formula (1), R １ represents an aliphatic hydrocarbon group having 2 to 8 carbon atoms.

[0034] The epoxy resin produced by the epoxy resin production method of the present embodiment preferably contains an epoxy compound represented by the following formula (3) (hereinafter may be referred to as "epoxy compound (3)" or "epoxy resin (3)"), and preferably contains epoxy compound (3) and an epoxy compound represented by the following formula (4) (hereinafter may be referred to as "epoxy compound (4)" or "epoxy resin (4)").

[0035]

[0036] (In the above formulas (3) and (4), R ２ ~R １３ , X １ , n has the same meaning as in formula (2) described below. ２ ~R １３ , X １The same applies to the preferred values ​​of n.

[0037] The phenol compound, amine compound, compound (1), and epihalohydrin used in this embodiment may be commercially available industrially available products.

[0038] The phenol compound is not particularly limited as long as it is a compound having a phenol skeleton, but is preferably one represented by the following formula (2).

[0039]

[0040] In the above formula (2), X １ is a divalent linking group, and is a divalent hydrocarbon group having 1 to 13 carbon atoms, -O-, -S-, -SO ２ -, -C(CF ３ ) ２ - and -CO- or a direct bond, and R ２ ~R １３ are each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or an alkynyl group having 2 to 12 carbon atoms. n represents an integer of 0 to 10.

[0041] X １ is preferably a direct bond or a divalent hydrocarbon group having 1 to 13 carbon atoms. The divalent hydrocarbon group having 1 to 13 carbon atoms is preferably an aliphatic hydrocarbon group having 1 to 10 carbon atoms, and particularly preferably an alkylene group having 1 to 10 carbon atoms, which may be branched. X １ is more preferably a direct bond, a methylene group, or an isopropylidene group, and most preferably a direct bond. １ If there are multiple Xs, １ may be the same or different from each other.

[0042] R ２ ~R １３are each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or an alkynyl group having 2 to 12 carbon atoms, and the alkyl group, alkoxy group, aryl group, alkenyl group, and alkynyl group may have a substituent.

[0043] Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a neopentyl group, a tert-pentyl group, a cyclopentyl group, an n-hexyl group, an isohexyl group, a cyclohexyl group, an n-heptyl group, a cycloheptyl group, a methylcyclohexyl group, an n-octyl group, a cyclooctyl group, an n-nonyl group, a 3,3,5-trimethylcyclohexyl group, an n-decyl group, a cyclodecyl group, an n-undecyl group, an n-dodecyl group, a cyclododecyl group, a benzyl group, a methylbenzyl group, a dimethylbenzyl group, a trimethylbenzyl group, a naphthylmethyl group, a phenethyl group, and a 2-phenylisopropyl group.

[0044] Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, a sec-butoxy group, a tert-butoxy group, an n-pentoxy group, an isopentoxy group, a neopentoxy group, a tert-pentoxy group, a cyclopentoxy group, an n-hexyloxy group, an isohexyloxy group, a cyclohexyloxy group, an n-heptoxy group, a cycloheptoxy group, a methylcyclohexyloxy group, an n-octoxy group, and the like. Examples of the alkyl group include a thyloxy group, a cyclooctyloxy group, an n-nonyloxy group, a 3,3,5-trimethylcyclohexyloxy group, an n-decyloxy group, a cyclodecyloxy group, an n-undecyloxy group, an n-dodecyloxy group, a cyclododecyloxy group, a benzyloxy group, a methylbenzyloxy group, a dimethylbenzyloxy group, a trimethylbenzyloxy group, a naphthylmethoxy group, a phenethyloxy group, and a 2-phenylisopropoxy group.

[0045] Examples of the alkenyl group include a vinyl group, a 1-propenyl group, a 2-propenyl group, a 1-methylvinyl group, a 1-butenyl group, a 2-butenyl group, a 3-butenyl group, a 1,3-butadienyl group, a cyclohexenyl group, a cyclohexadienyl group, a cinnamyl group, and a naphthylvinyl group.

[0046] Examples of the alkynyl group include an ethynyl group, a 1-propynyl group, a 2-propynyl group, a 1-butynyl group, a 2-butynyl group, a 3-butynyl group, a 1,3-butadienyl group, a phenylethynyl group, and a naphthylethynyl group.

[0047] Examples of the aryl group include a phenyl group, an o-tolyl group, an m-tolyl group, a p-tolyl group, an ethylphenyl group, a styryl group, a xylyl group, an n-propylphenyl group, an isopropylphenyl group, a mesityl group, an ethynylphenyl group, a naphthyl group, and a vinylnaphthyl group.

[0048] R ２ ~R １３ are preferably each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and more preferably each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms.

[0049] In formula (2), n is an integer of 0 to 10, preferably 0 to 5, and more preferably 0 to 3.

[0050] Specific examples of the raw material phenol compound include bisphenol compounds such as bisphenol A, bisphenol F, bisphenol S, bisphenol AD, and bisphenol AF; biphenol compounds such as biphenol and tetramethylbiphenol; dihydroxydiphenyl ethers; thiodiphenols; phenol novolac resins, cresol novolac resins, phenol aralkyl resins, biphenyl aralkyl resins, naphthol aralkyl resins, terpene phenol resins, dicyclopentadiene phenol resins, bisphenol A novolac resins, naphthol novolac resins, brominated bisphenol A, and brominated phenol novolac resins; and various phenolic resins such as polyhydric phenol resins obtained by condensation reactions of various phenols with various aldehydes such as benzaldehyde and crotonaldehyde; and polyhydric phenol resins obtained by condensation reactions of xylene resins with phenols. Of these, bisphenol compounds or biphenol compounds are preferred, with biphenol compounds being more preferred, and tetramethylbiphenol being particularly preferred.

[0051] The raw material amine compound is not particularly limited as long as it is a compound having an amine skeleton, and examples thereof include p-aminophenol, m-aminophenol, o-aminophenol, diaminodiphenylmethane, diethylenetriamine, triethylenetetramine, diaminodiphenylsulfone, isophoronediamine, imidazole, BF3-amine complex, and guanidine derivatives.

[0052] Substituent R in the formula (1) representing compound (1) １ is an aliphatic hydrocarbon group having 2 to 8 carbon atoms.

[0053] R １ is an aliphatic hydrocarbon group having 2 to 8 carbon atoms, the structure is not particularly limited, and may be a straight chain or a non-straight chain structure such as a branched structure or a cyclic structure. １ The aliphatic hydrocarbon group having 2 to 8 carbon atoms may have a substituent such as a phenyl group or an alkoxy group.

[0054] The linear aliphatic hydrocarbon group is preferably a linear alkyl group having 2 to 8 carbon atoms. Specific examples include an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, and an n-octyl group, and is preferably a linear alkyl group having 2 to 4 carbon atoms. Specific examples include an ethyl group, an n-propyl group, and an n-butyl group.

[0055] In the case of a non-linear structure such as a branched structure or a cyclic structure, a non-linear aliphatic hydrocarbon group having 3 to 8 carbon atoms is preferred. Specific examples include an isopropyl group, a 1-methoxy-2-propyl group, a sec-butyl group, a tert-butyl group, an isopentyl group, a neopentyl group, a tert-pentyl group, a cyclopentyl group, an isohexyl group, a cyclohexyl group, a cycloheptyl group, a methylcyclohexyl group, a cyclooctyl group, a benzyl group, and a methylbenzyl group. More preferred are branched alkyl groups having 3 to 8 carbon atoms, such as an isopropyl group, a 1-methoxy-2-propyl group, a sec-butyl group, a tert-butyl group, an isopentyl group, a neopentyl group, and a tert-pentyl group. The branched chain may contain an oxygen atom by having an alkoxy group as a substituent.

[0056] The proportion of compound (1) used is preferably 0.01 to 19% by mass, more preferably 0.1 to 12% by mass, and even more preferably 1.0 to 8.0% by mass, relative to the raw material epihalohydrin. As this proportion increases, the melting point of the resulting epoxy resin tends to be lower and the fluidity at low temperatures tends to be higher. Furthermore, as this proportion decreases, the crystallization time tends to be shorter and productivity tends to be improved.

[0057] The epihalohydrin is not particularly limited, but examples thereof include epichlorohydrin, epibromohydrin, β-methylepichlorohydrin, etc. Among these, epichlorohydrin is preferred because it is easily available industrially.

[0058] When a phenol compound is used as the raw material, the epihalohydrin is preferably used in an amount of 1 to 10 moles per mole of hydroxyl groups contained in the raw phenol compound, and a preferred method includes a method in which 0.9 to 2.0 moles of alkaline catalyst per mole of hydroxyl groups contained in the raw phenol compound is added all at once or gradually, while the reaction is carried out for 0.5 to 10 hours at a temperature of 20 to 120° C. The alkaline catalyst may be a solid or an aqueous solution thereof. When an aqueous solution is used, the alkaline catalyst may be added continuously, and water and epihalohydrins may be continuously distilled from the reaction mixture under reduced pressure or normal pressure, and the water may be removed by liquid separation while the epihalohydrins are continuously returned to the reaction mixture.

[0059] When an amine compound is used as the raw material, the epihalohydrin is preferably used in an amount of 2 to 20 moles per mole of amino groups contained in the raw amine compound, and a preferred method includes a method in which 1.8 to 4.0 moles of alkaline catalyst per mole of amino groups in the raw material is added all at once or gradually, while the reaction is carried out for 0.5 to 10 hours at a temperature of 20 to 120° C. The alkaline catalyst may be a solid or an aqueous solution thereof. When an aqueous solution is used, the alkaline catalyst may be added continuously, and water and epihalohydrins may be continuously distilled from the reaction mixture under reduced pressure or normal pressure, and the water may be removed by liquid separation while the epihalohydrins are continuously returned to the reaction mixture.

[0060] In industrial production, all of the epihalohydrins used in charging the first batch of epoxy resin production are fresh, but from the next batch onwards, it is preferable to use in combination epihalohydrins recovered from the crude reaction product and fresh epihalohydrins equivalent to the amount consumed and lost in the reaction.

[0061] In the present embodiment, from the viewpoint of easily adjusting the content of the epoxy compound (3) in the epoxy resin to a suitable range, the reaction temperature is preferably in the range of 20 to 90°C, and the reaction time is preferably in the range of 0.5 to 10 hours.

[0062] Specific examples of the alkaline catalyst include alkaline earth metal hydroxides, alkali metal carbonates, and alkali metal hydroxides. In particular, alkali metal hydroxides are preferred because they have excellent catalytic activity in the epoxy resin synthesis reaction, and examples include sodium hydroxide and potassium hydroxide. When used, these alkaline catalysts may be used in the form of an aqueous solution of about 10 to 55 mass %, or may be used in the form of a solid.

[0063] In the reaction of this embodiment, the reaction rate in the synthesis of the epoxy resin can be increased by using an organic solvent in combination. The amount of the organic solvent used is preferably 5 to 70 parts by mass per 100 parts by mass of the epihalohydrin.

[0064] The organic solvent used in the reaction is not particularly limited, and examples thereof include ketones such as acetone and methyl ethyl ketone, alcohols such as methanol, ethanol, 1-propyl alcohol, isopropyl alcohol, 1-butanol, sec-butanol, and tert-butanol, cellosolves such as methyl cellosolve and ethyl cellosolve, ethers such as tetrahydrofuran, 1,4-dioxane, 1,3-dioxane, and diethoxyethane, and aprotic polar solvents such as acetonitrile, dimethyl sulfoxide, and dimethylformamide. These organic solvents may be used alone, or two or more of them may be used in combination as appropriate to adjust the polarity.

[0065] Furthermore, from the viewpoint of suitably obtaining the epoxy resin of this embodiment, it is preferable to use a combination of the organic solvent described above and water as the reaction solvent. In this case, the proportion of water used in the mixed solvent is preferably in the range of 5 to 60 parts by mass, and particularly preferably in the range of 10 to 50 parts by mass, per 100 parts by mass of the mixed solvent. If the proportion is equal to or greater than the lower limit, a sudden increase in temperature during the reaction can be suppressed. If the proportion is equal to or less than the upper limit, a decrease in the alkaline catalyst concentration can be suppressed, thereby preventing a decrease in the epoxidation reaction rate.

[0066] When the alkaline catalyst used in the epoxidation reaction is in the form of an aqueous solution, the content of water contained in the aqueous solution is not included in the amount of water defined as being in the mixed solvent.

[0067] The epoxy resin produced as described above can be purified by reacting it again with an alkali to obtain the epoxy resin composition of the present embodiment containing the epoxy compound (3), the epoxy compound (4), and other components in suitable contents described below.

[0068] In this case, an organic solvent for dissolving the epoxy resin may be used in the reaction between the epoxy resin and the alkali. The organic solvent used in the reaction is not particularly limited, but it is preferable to use a ketone-based organic solvent in terms of production efficiency, handling, workability, etc. From the viewpoint of further reducing the amount of hydrolyzable chlorine, an aprotic polar solvent may also be used.

[0069] Examples of ketone-based organic solvents include ketone-based solvents such as methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone. Methyl isobutyl ketone is particularly preferred in terms of effectiveness and ease of post-treatment. These solvents may be used alone or in combination of two or more.

[0070] Examples of aprotic polar solvents include dimethyl sulfoxide, diethyl sulfoxide, dimethyl sulfone, sulfolane, dimethylformamide, dimethylacetamide, and hexamethylphosphoramide. These may be used alone or in combination of two or more. Among these aprotic polar solvents, dimethyl sulfoxide is preferred because it is easily available and has excellent effects.

[0071] When a ketone organic solvent and an aprotic polar solvent are used in combination, the proportion of the aprotic polar solvent is preferably 1 to 30% by mass, particularly 5 to 20% by mass, based on the total of the two.

[0072] The amount of organic solvent used is such that the concentration of the epoxy resin in the liquid to be subjected to the alkali treatment is usually 3 to 70 mass %, preferably 5 to 50 mass %, and more preferably 10 to 40 mass %.

[0073] As the alkali, a solid or solution of an alkali metal hydroxide can be used. Examples of the alkali metal hydroxide include potassium hydroxide and sodium hydroxide, with sodium hydroxide being preferred. The alkali metal hydroxide may be dissolved in an organic solvent or water. Preferably, the alkali metal hydroxide is used as a solution dissolved in a water solvent or an organic solvent.

[0074] The amount of alkali metal hydroxide used is preferably 0.1 parts by mass or more and 6.0 parts by mass or less, calculated as the solid content of the alkali metal hydroxide, per 100 parts by mass of the epoxy resin. By using the alkali metal hydroxide in this range, it becomes possible to easily adjust the ratio of each component of the obtained epoxy resin composition to within a suitable range. If the amount of alkali metal hydroxide is outside the above range, it may not be possible to obtain an epoxy resin composition containing epoxy compound (3), epoxy compound (4), and other components in which the ratio of each component falls within the suitable range.

[0075] The reaction temperature is preferably 20 to 150°C, more preferably 30 to 90°C. The reaction time is preferably 0.1 to 15 hours, more preferably 0.3 to 10 hours. If the reaction temperature is outside the above range, it may not be possible to obtain an epoxy resin composition containing epoxy compound (3), epoxy compound (4), and other components in a proportion within the preferred range for each component.

[0076] After the reaction, excess alkali metal hydroxide and secondary salts are removed by a method such as washing with water, and the organic solvent is further removed by vacuum distillation and / or steam distillation, thereby obtaining the epoxy resin composition of the present embodiment.

[0077] [Epoxy Compound (3)] The epoxy resin obtained by the above-described method for producing an epoxy resin of this embodiment is preferably an epoxy compound (3) represented by formula (3). The epoxy resin obtained by the method for producing an epoxy resin of this embodiment preferably contains 70.0 to 99.9 mass% of epoxy compound (3), more preferably 80.0 to 97.0 mass%, and even more preferably 82.0 to 94.0 mass% of epoxy compound (3).

[0078]

[0079] In formula (3), R ２ ~R １３ , X １ , n has the same meaning as in the above formula (2). ２ ~R １３ , X １ The same applies to the preferred values ​​of each of n.

[0080] Specific examples of the epoxy compound (3) include bisphenol compounds such as bisphenol A, bisphenol F, bisphenol S, bisphenol AD, and bisphenol AF, biphenol compounds such as biphenol and tetramethylbiphenol, dihydroxydiphenyl ether, thiodiphenols, phenol novolac resin, cresol novolac resin, phenol aralkyl resin, biphenyl aralkyl resin, naphthol aralkyl resin, terpene phenol resin, dicyclopentadiene phenol resin, bisphenol A novolac resin, naphthol novolac resin, brominated bisphenol A, and brominated phenol novolac resin. Examples of epoxy resins include those in which the hydroxyl groups of various phenolic resins, such as various polyhydric phenols such as those listed above, polyhydric phenol resins obtained by the condensation reaction of various phenols with various aldehydes such as benzaldehyde and crotonaldehyde, and polyhydric phenol resins obtained by the condensation reaction of xylene resin with phenols, are converted to epoxy groups. However, preferred are epoxy resins in which the hydroxyl groups of bisphenol compounds or biphenol compounds are converted to epoxy groups, more preferred are epoxy resins in which the hydroxyl groups of biphenol compounds are converted to epoxy groups, and particularly preferred are epoxy resins in which the hydroxyl groups of tetramethylbiphenol are converted to epoxy groups.

[0081] [Epoxy Compound (4)] The epoxy resin obtained by the epoxy resin production method of this embodiment preferably contains, together with the epoxy compound (3), an epoxy compound (4) represented by the following formula (4): The epoxy resin obtained by the epoxy resin production method of this embodiment preferably contains 0.1 to 8.0 mass% of the epoxy compound (4), and the content of the epoxy compound (4) is more preferably 0.2 to 5.0 mass%, and even more preferably 0.4 to 3.0 mass%.

[0082]

[0083] In the above formula (4), X １ , R ２ ~R １３ , n has the same meaning as in the formula (2) and the formula (3), R １has the same meaning as in the formula (1). １ ~R １３ , X １ The same applies to the preferred values ​​of each of n.

[0084] [Other Components] The epoxy resin obtained by the epoxy resin production method of this embodiment may further contain other components (hereinafter simply referred to as "other components") in addition to these epoxy compounds (3) and (4). The content of other components in the epoxy resin obtained by the epoxy resin production method of this embodiment is preferably 15.0 mass% or less. When the epoxy resin obtained by the epoxy resin production method of this embodiment contains other components, the total of the epoxy compound (3), the epoxy compound (4), and the other components is 100 mass%.

[0085] [Epoxy resin composition (A)] The epoxy resin composition (A), which is a second embodiment of the present invention, is characterized by containing 80.0 to 99.9 mass% of the epoxy compound (3) represented by the above formula (3), i.e., the epoxy resin (3), and 0.1 to 8.0 mass% of the epoxy compound represented by the following formula (5) (hereinafter, may be referred to as "epoxy compound (5)" or "epoxy resin (5)"):

[0086]

[0087] (In the above formula (5), X １ , R ２ ~R １３ , n has the same meaning as in the formula (2) and formula (3). ２ ~R １３ , X １ The same applies to the preferred values ​​of R, n. １４ is a non-linear aliphatic hydrocarbon group having 3 to 8 carbon atoms.

[0088] R in formula (5) １４ The structure of is not particularly limited as long as it is a non-linear aliphatic hydrocarbon group having 3 to 8 carbon atoms, and may be a branched structure, a cyclic structure, etc. Furthermore, it may have a substituent such as a phenyl group or an alkoxy group.

[0089] R １４ Specific examples of the non-linear aliphatic hydrocarbon group having 3 to 8 carbon atoms include an isopropyl group, a 1-methoxy-2-propyl group, a sec-butyl group, a tert-butyl group, an isopentyl group, a neopentyl group, a tert-pentyl group, a cyclopentyl group, an isohexyl group, a cyclohexyl group, a cycloheptyl group, a methylcyclohexyl group, a cyclooctyl group, a benzyl group, and a methylbenzyl group, and more preferably, a branched alkyl group having 3 to 8 carbon atoms, such as an isopropyl group, a 1-methoxy-2-propyl group, a sec-butyl group, a tert-butyl group, an isopentyl group, a neopentyl group, and a tert-pentyl group. The branched chain may contain an oxygen atom by having an alkoxy group as a substituent.

[0090] The content of epoxy resin (3) in the epoxy resin composition (A) of this embodiment is 80.0 to 99.9% by mass, preferably 82.0 to 97.0%, and more preferably 85.0 to 94.0% by mass. If the content of epoxy resin (3) exceeds the upper limit, the melting point will be high, it will take time for fluidity to develop, and productivity will be poor when mixed with other components such as the curing agent described below. On the other hand, if the content of epoxy resin (3) is less than the lower limit, the crystallization time during production of the epoxy resin composition will be long, resulting in poor productivity.

[0091] The content of epoxy resin (5) in the epoxy resin composition (A) of this embodiment is 0.1 to 8.0 mass%, preferably 0.2 to 5.0 mass%, and more preferably 0.4 to 3.0 mass%. If the content of epoxy resin (5) is less than the above lower limit, the melting point will be high, it will take time for fluidity to develop, and productivity will be poor when mixing with other components such as the curing agent described below. On the other hand, if the content of epoxy resin (5) exceeds the above upper limit, the glass transition temperature of a cured product using the epoxy resin composition will be low.

[0092] The epoxy resin composition (A) of this embodiment may further contain other components (hereinafter simply referred to as "other components") in addition to the epoxy resin (3) and the epoxy resin (5). The content of the other components in the epoxy resin composition (A) is preferably 15.0 mass% or less. When the epoxy resin composition (A) of this embodiment contains other components, the total of the epoxy resin (3), the epoxy resin (5), and the other components is 100 mass%.

[0093] The content of the epoxy resin (5) in the epoxy resin composition (A) can be controlled by adjusting the amount of the compound (6) described below, which is used in the method for producing an epoxy resin of this embodiment. That is, the more the compound (6) is used, the higher the content of the epoxy resin (5) can be, and the less the compound (6) is used, the lower the content of the epoxy resin (5) can be.

[0094] The content of each of the components of the epoxy resin composition (A) of the present embodiment can be measured, for example, by high performance liquid chromatography analysis (hereinafter, referred to as LC analysis).

[0095] The epoxy resin composition (A) of this embodiment is defined as an "epoxy resin composition" because it contains multiple components, such as epoxy resin (3) and epoxy resin (5). However, in the technical field of epoxy resins, an "epoxy resin" is not composed of a single component, but is obtained as a "composition" composed of multiple components. For this reason, the epoxy resin composition (A) of this embodiment is referred to as an "epoxy resin" in the industry and is sometimes sold as an "epoxy resin." Furthermore, in the industry, "epoxy compounds (uncured)" are also referred to as "epoxy resins." For this reason, both the compound represented by formula (3) and the compound represented by formula (5) are referred to as "epoxy resins."

[0096] From the viewpoint of obtaining excellent electrical properties as an epoxy resin and excellent productivity as an epoxy resin composition (B) containing a curing agent, the epoxy resin composition (A) of this embodiment preferably has an epoxy equivalent of 180 to 193 g / eq, for example, when tetramethylbiphenol is used as a raw material. From the viewpoint of further improving productivity during production of the epoxy resin composition (A), it is more preferable that the epoxy equivalent of the epoxy resin composition (A) of this embodiment be 184 to 192 g / eq, for example, when tetramethylbiphenol is used as a raw material. It is believed that by setting the epoxy equivalent within the above specific range, the above-mentioned excellent properties can be obtained.

[0097] In the present embodiment, the term "epoxy equivalent" is defined as "the mass of an epoxy resin containing one equivalent of epoxy groups," and can be measured in accordance with JIS K7236.

[0098] The epoxy resin composition (A) of the present embodiment preferably has a hydrolyzable chlorine content (hereinafter sometimes referred to as the "hydrolyzable chlorine amount") of 1,000 ppm by mass or less. From the viewpoint of improving electrical properties, the hydrolyzable chlorine amount in the epoxy resin composition (A) is more preferably 700 ppm by mass or less.

[0099] The amount of hydrolyzable chlorine can be determined, for example, by dissolving about 0.5 g of epoxy resin in 20 mL of dioxane, refluxing the solution with 5 mL of 1N KOH / ethanol solution for 30 minutes, and then titrating the solution with 0.01N silver nitrate solution.

[0100] In order to reduce the amount of hydrolyzable chlorine in the epoxy resin composition (A), as described above, the epoxy resin produced in the method for producing an epoxy resin of the first embodiment may be further reacted with an alkali to purify the epoxy resin.

[0101] The melting point of the epoxy resin composition (A) of this embodiment is preferably 108°C or lower. If the melting point is equal to or lower than this value, the epoxy resin composition (B) described below can be mixed at a lower temperature during production, and production can be carried out under conditions with a lower environmental impact. On the other hand, the melting point of the epoxy resin composition (A) of this embodiment is preferably 50°C or higher from the viewpoint of preventing melting at high temperatures during transportation.

[0102] The crystallization time of the epoxy resin composition (A) of this embodiment is preferably 1,500 seconds or less, more preferably 1,000 seconds or less. When the crystallization time is this value or less, the epoxy resin composition (B) can be solidified in a short time in the production process, resulting in excellent productivity. On the other hand, from the viewpoint of preventing adhesion due to crystallization at the discharge port during epoxy resin production, the crystallization time of the epoxy resin composition (A) of this embodiment is preferably 60 seconds or more.

[0103] <Production method of epoxy resin composition (A)> The production method of the epoxy resin composition (A) of the present embodiment is not particularly limited, but the epoxy resin composition (A) can be produced in the same manner as the production method of the epoxy resin of the first embodiment described above, except that when a starting material phenol compound and epihalohydrin are reacted to produce an epoxy resin in the presence of compound (1), a compound represented by the following formula (6) (hereinafter, may be referred to as "compound (6)") is used instead of compound (1) to produce epoxy resin (5) instead of epoxy compound (4). The same applies to preferred embodiments of each of the compositions, and redundant descriptions will be omitted.

[0104]

[0105] (In the above formula (6), R １４ has the same meaning as in the formula (5). １４ The same applies to the preferred ones.)

[0106] [Epoxy resin composition (B)] The epoxy resin composition (B) of the third embodiment of the present invention contains at least the epoxy resin composition (A) of the second embodiment described above and a curing agent. If necessary, the epoxy resin composition (B) of this embodiment may appropriately contain other epoxy resins (hereinafter simply referred to as "other epoxy resins") other than the epoxy resin contained in the epoxy resin composition (A) of the second embodiment, a curing accelerator, an inorganic filler, a coupling agent, etc.

[0107] [Curing Agent] In the present embodiment, the curing agent refers to a substance that contributes to the crosslinking reaction between epoxy groups of an epoxy resin and / or the chain extension reaction. In the present invention, even substances that are usually called "curing accelerators" are considered to be curing agents as long as they contribute to the crosslinking reaction between epoxy groups of an epoxy resin and / or the chain extension reaction.

[0108] In the epoxy resin composition (B) of this embodiment, the content of the curing agent is preferably 0.1 to 1,000 parts by mass, more preferably 500 parts by mass or less, and even more preferably 300 parts by mass or less, per 100 parts by mass of the total epoxy resin components as solid content. In this embodiment, the "solid content" refers to the components excluding the solvent, and includes not only solid epoxy resins but also semi-solid and viscous liquids. The "total epoxy resin components" corresponds to the amount of epoxy resin contained in the epoxy resin composition (B) of this embodiment. When the epoxy resin composition (B) of this embodiment contains only the epoxy resin composition (A), the "total epoxy resin components" refers to the amount of epoxy resin in the epoxy resin composition (A) (epoxy resin (3) and epoxy resin (5) and epoxy resins other than the epoxy resin (3) and epoxy resin (5) in other components). When the epoxy resin composition (B) of this embodiment contains the epoxy resin composition (A) and other epoxy resins, the "total epoxy resin components" corresponds to the total amount of the epoxy resins in the epoxy resin composition (A) and other epoxy resins.

[0109] The curing agent is not particularly limited, and any of those generally known as epoxy resin curing agents can be used, including, for example, phenol-based curing agents, amine-based curing agents such as aliphatic amines, polyether amines, alicyclic amines, and aromatic amines, acid anhydride-based curing agents, amide-based curing agents, tertiary amines, and imidazoles.

[0110] Among these, by including a phenol-based curing agent, the epoxy resin composition (B) of this embodiment can obtain excellent heat resistance, stress resistance, water absorption resistance, flame retardancy, and the like. For this reason, it is preferable to include a phenol-based curing agent as the curing agent. From the viewpoint of heat resistance, it is preferable to include an acid anhydride-based curing agent or an amide-based curing agent. It is also preferable to use imidazoles from the viewpoint of sufficiently progressing the curing reaction and improving heat resistance.

[0111] The curing agent may be used alone or in combination of two or more. When two or more curing agents are used in combination, they may be mixed in advance to prepare a mixed curing agent before use, or when mixing the components of the epoxy resin composition (B), each component of the curing agent may be added separately and mixed simultaneously.

[0112] <Phenol-based curing agent> Specific examples of the phenol-based curing agent include various polyhydric phenols such as bisphenol A, bisphenol F, bisphenol S, bisphenol AD, hydroquinone, resorcinol, methylresorcinol, biphenol, tetramethylbiphenol, dihydroxynaphthalene, dihydroxydiphenyl ether, thiodiphenols, phenol novolac resin, cresol novolac resin, phenol aralkyl resin, biphenyl aralkyl resin, naphthol aralkyl resin, terpene phenol resin, dicyclopentadiene phenol resin, bisphenol A novolac resin, trisphenolmethane type resin, naphthol novolac resin, brominated bisphenol A, and brominated phenol novolac resin. Examples of the polyhydric phenol resin include polyhydric phenol resins obtained by the condensation reaction of phenols with various aldehydes such as benzaldehyde, hydroxybenzaldehyde, crotonaldehyde, and glyoxal, polyhydric phenol resins obtained by the condensation reaction of xylene resin and phenols, co-condensation resins of heavy oils or pitches with phenols and formaldehydes, and various phenol resins such as phenol-benzaldehyde-xylylene dimethoxide polycondensates, phenol-benzaldehyde-xylylene dihalide polycondensates, phenol-benzaldehyde-4,4'-dimethoxide biphenyl polycondensates, and phenol-benzaldehyde-4,4'-dihalide biphenyl polycondensates.

[0113] The phenolic curing agent may be used alone or in any combination of two or more kinds in any blending ratio.

[0114] Among the above phenolic curing agents, from the viewpoint of heat resistance and curability after curing of the composition, phenol novolak resins (for example, compounds represented by the following formula (7)), phenol aralkyl resins (for example, compounds represented by the following formula (8)), biphenyl aralkyl resins (for example, compounds represented by the following formula (9)), naphthol novolak resins (for example, compounds represented by the following formula (10)), naphthol aralkyl resins (for example, compounds represented by the following formula (11)), trisphenol methane type resins (for example, compounds represented by the following formula (12)) Preferred are phenol-benzaldehyde-xylylene dimethoxide polycondensates (for example, compounds represented by the following formula (13)), phenol-benzaldehyde-xylylene dihalide polycondensates (for example, compounds represented by the following formula (13)), phenol-benzaldehyde-4,4'-dimethoxide biphenyl polycondensates (for example, compounds represented by the following formula (14)), and phenol-benzaldehyde-4,4'-dihalide biphenyl polycondensates (for example, compounds represented by the following formula (14)). Particularly preferred are phenol novolak resins (for example, compounds represented by the following formula (7)), phenol aralkyl resins (for example, compounds represented by the following formula (8)), biphenyl aralkyl resins (for example, compounds represented by the following formula (9)), phenol-benzaldehyde-xylylene dimethoxide polycondensates (for example, compounds represented by the following formula (13)), phenol-benzaldehyde-xylylene dihalide polycondensates (for example, compounds represented by the following formula (13)), phenol-benzaldehyde-4,4'-dimethoxide biphenyl polycondensates (for example, compounds represented by the following formula (14)), and phenol-benzaldehyde-4,4'-dihalide biphenyl polycondensates (for example, compounds represented by the following formula (14)).

[0115]

[0116] (In the above formulas (7) to (12), k １ ~k ６ indicates a number greater than or equal to 0.)

[0117]

[0118] (In the above formulas (13) and (14), k ７ , k８ , l １ , l ２ indicates a number greater than or equal to 1.)

[0119] The amount of the phenolic curing agent to be blended is preferably 0.1 to 1,000 parts by mass, more preferably 500 parts by mass or less, even more preferably 300 parts by mass or less, and particularly preferably 100 parts by mass or less, based on 100 parts by mass of all epoxy resin components in the epoxy resin composition (B).

[0120] <Amine-Based Curing Agent> Examples of the amine-based curing agent (excluding tertiary amines) include aliphatic amines, polyether amines, alicyclic amines, and aromatic amines.

[0121] Examples of aliphatic amines include ethylenediamine, 1,3-diaminopropane, 1,4-diaminopropane, hexamethylenediamine, 2,5-dimethylhexamethylenediamine, trimethylhexamethylenediamine, diethylenetriamine, iminobispropylamine, bis(hexamethylene)triamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, N-hydroxyethylethylenediamine, and tetra(hydroxyethyl)ethylenediamine.

[0122] Examples of polyetheramines include triethylene glycol diamine, tetraethylene glycol diamine, diethylene glycol bis(propylamine), polyoxypropylene diamine, polyoxypropylene triamines, and the like.

[0123] Examples of alicyclic amines include isophoronediamine, methacenediamine, N-aminoethylpiperazine, bis(4-amino-3-methyldicyclohexyl)methane, bis(aminomethyl)cyclohexane, 3,9-bis(3-aminopropyl)-2,4,8,10-tetraoxaspiro(5,5)undecane, and norbornenediamine.

[0124] Examples of aromatic amines include tetrachloro-p-xylylenediamine, m-xylylenediamine, p-xylylenediamine, m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, 2,4-diaminoanisole, 2,4-toluenediamine, 2,4-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 4,4'-diamino-1,2-diphenylethane, 2,4-diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfone, m-aminophenol, m-aminobenzylamine, benzyldimethylamine, 2-(dimethylaminomethyl)phenol, triethanolamine, methylbenzylamine, α-(m-aminophenyl)ethylamine, α-(p-aminophenyl)ethylamine, diaminodiethyldimethyldiphenylmethane, and α,α'-bis(4-aminophenyl)-p-diisopropylbenzene.

[0125] The amine-based curing agent may be used alone or in any combination of two or more kinds in any blending ratio.

[0126] The amine-based curing agent is preferably used so that the equivalent ratio of the functional groups in the curing agent to the epoxy groups in all epoxy resin components contained in the epoxy resin composition (B) is in the range of 0.8 to 1.5, since within this range, unreacted epoxy groups and functional groups of the curing agent are less likely to remain.

[0127] Examples of tertiary amines include 1,8-diazabicyclo(5,4,0)undecene-7, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris(dimethylaminomethyl)phenol.

[0128] The tertiary amines may be used alone or in any combination of two or more in any ratio.

[0129] The tertiary amine is preferably used so that the equivalent ratio of the functional groups in the curing agent to the epoxy groups in all epoxy resin components contained in the epoxy resin composition (B) is in the range of 0.8 to 1.5, since within this range, unreacted epoxy groups and functional groups of the curing agent are less likely to remain.

[0130] <Acid Anhydride Curing Agent> Examples of the acid anhydride curing agent include acid anhydrides and modified acid anhydrides.

[0131] Examples of acid anhydrides include phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic anhydride, dodecenylsuccinic anhydride, polyadipic anhydride, polyazelaic anhydride, polysebacic anhydride, poly(ethyloctadecanedioic) anhydride, poly(phenylhexadecanedioic) anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydrophthalic anhydride, methylhimic anhydride, trialkyltetrahydrophthalic anhydride, Examples of such an anhydride include methylcyclohexene dicarboxylic acid anhydride, methylcyclohexene tetracarboxylic acid anhydride, ethylene glycol bistrimellitate dianhydride, HET anhydride, Nadic anhydride, methylnadic anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclohexane-1,2-dicarboxylic acid anhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic acid dianhydride, and 1-methyl-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic acid dianhydride.

[0132] Examples of modified acid anhydrides include those obtained by modifying the above-mentioned acid anhydrides with glycols. Examples of glycols that can be used for modification include alkylene glycols such as ethylene glycol, propylene glycol, and neopentyl glycol, and polyether glycols such as polyethylene glycol, polypropylene glycol, and polytetramethylene ether glycol. Furthermore, copolymer polyether glycols of two or more of these glycols and / or polyether glycols can also be used.

[0133] In the case of modified acid anhydrides, it is preferable to modify the acid anhydride with 0.4 moles or less of glycol per mole of acid anhydride. When the modification amount is not more than the upper limit, the viscosity of the epoxy resin composition does not become too high, and workability tends to be improved. In addition, the rate of the curing reaction with the epoxy resin also tends to be improved.

[0134] The acid anhydride curing agents may be used alone or in any combination of two or more in any amount.

[0135] When an acid anhydride curing agent is used, it is preferable to use it so that the equivalent ratio of the functional groups in the curing agent to the epoxy groups in all epoxy resin components in the epoxy resin composition (B) is in the range of 0.8 to 1.5, since it is preferable if it is within this range because unreacted epoxy groups and functional groups of the curing agent are less likely to remain.

[0136] <Amide-based curing agent> Examples of the amide-based curing agent include dicyandiamide and its derivatives, polyamide resins, etc. The amide-based curing agent may be used alone or in any combination and ratio of two or more kinds.

[0137] When an amide curing agent is used, it is preferable to use the amide curing agent in an amount of 0.1 to 20 mass % based on the total amount of all epoxy resin components and the amide curing agent in the epoxy resin composition (B).

[0138] <Imidazoles> Examples of imidazoles include 2-phenylimidazole, 2-ethyl-4(5)-methylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyano-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6-[2′-methylimidazolyl- Examples of the imidazole compound include 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, and adducts of epoxy resins with the above imidazoles. Since imidazoles have catalytic activity, they can generally be classified as curing accelerators, but in this embodiment they are classified as curing agents.

[0139] The imidazoles may be used alone or in any combination and ratio of two or more.

[0140] When imidazoles are used, the amount of the imidazoles is preferably 0.1 to 20% by mass based on the total amount of all epoxy resin components and imidazoles in the epoxy resin composition (B).

[0141] <Other Curing Agents> In addition to the above curing agents, other curing agents can be used in the epoxy resin composition (B) of this embodiment. There are no particular restrictions on the other curing agents, and any curing agent generally known as a curing agent for epoxy resins can be used. The other curing agents may be used alone or in combination of two or more.

[0142] [Other Epoxy Resins] The epoxy resin composition (B) of the present embodiment may further contain other epoxy resins in addition to the epoxy resin composition (A). By including other epoxy resins, the heat resistance, stress resistance, water absorption resistance, flame retardancy, etc. of the epoxy resin composition (B) of the present invention can be improved.

[0143] The other epoxy resins that can be used in the epoxy resin composition (B) of this embodiment include all epoxy resins other than the epoxy resins contained in the epoxy resin composition (A) (mainly the epoxy resin (3) and the epoxy resin (5)).Specific examples include bisphenol A type epoxy resins, trisphenolmethane type epoxy resins, anthracene type epoxy resins, phenol-modified xylene resin type epoxy resins, bisphenolcyclododecyl type epoxy resins, bisphenoldiisopropylideneresorcin type epoxy resins, bisphenol F type epoxy resins, bisphenol AD ​​type epoxy resins, hydroquinone type epoxy resins, methylhydroquinone type epoxy resins, dibutylhydroquinone type epoxy resins, resorcin type epoxy resins, methylresorcin type epoxy resins, biphenol type epoxy resins, tetramethylbiphenol type epoxy resins other than the epoxy resins (1) and (2) in the epoxy resin composition (A), tetramethylbisphenol F type epoxy resins, dihydroxydiphenyl ether type epoxy resins, epoxy resins derived from thiodiphenols, dihydroxynaphthalene type epoxy resins, dihydroxyanthracene type epoxy resins, dihydroxydihydroanthracene type epoxy resins, dicyclopentadiene type epoxy resins, dihydroxy Examples of epoxy resins include epoxy resins derived from cystilbenes, phenol novolac epoxy resins, cresol novolac epoxy resins, bisphenol A novolac epoxy resins, naphthol novolac epoxy resins, phenol aralkyl epoxy resins, naphthol aralkyl epoxy resins, biphenyl aralkyl epoxy resins, terpene phenol epoxy resins, dicyclopentadiene phenol epoxy resins, epoxy resins derived from a phenol-hydroxybenzaldehyde condensate, epoxy resins derived from a phenol-crotonaldehyde condensate, epoxy resins derived from a phenol-glyoxal condensate, epoxy resins derived from a co-condensation resin of heavy oil or pitches, phenols, and formaldehydes, epoxy resins derived from diaminodiphenylmethane, epoxy resins derived from aminophenols, epoxy resins derived from xylenediamine, epoxy resins derived from methylhexahydrophthalic acid, and epoxy resins derived from dimer acids.

[0144] These may be used alone or in any combination of two or more in any blending ratio.

[0145] Among the above epoxy resins, from the viewpoints of the fluidity of the composition and further the heat resistance, water absorption resistance, flame retardancy, and the like of the cured product, bisphenol A type epoxy resins, tetramethylbiphenol type epoxy resins other than the epoxy resins (3) and (5) in the epoxy resin composition (A), 4,4'-biphenol type epoxy resins, biphenylaralkyl type epoxy resins, phenolaralkyl type epoxy resins, dihydroxyanthracene type epoxy resins, dicyclopentadiene type epoxy resins, orthocresol novolac type epoxy resins, and trisphenolmethane type epoxy resins are particularly preferred.

[0146] When the epoxy resin composition (B) of the present embodiment contains the other epoxy resins described above, the content thereof is preferably 0.01 to 60 parts by mass, more preferably 40 parts by mass or less, even more preferably 30 parts by mass or less, particularly preferably 20 parts by mass or less, and more preferably 1 part by mass or more, relative to 100 parts by mass of all epoxy resin components in the composition.

[0147] [Curing Accelerator] The epoxy resin composition (B) of the present embodiment preferably contains a curing accelerator. By including a curing accelerator, it is possible to shorten the curing time and lower the curing temperature, making it easier to obtain a desired cured product.

[0148] The curing accelerator is not particularly limited, and specific examples thereof include organic phosphines, phosphorus compounds such as phosphonium salts, tetraphenylboron salts, organic acid dihydrazides, and boron halide amine complexes.

[0149] Examples of phosphorus compounds that can be used as a curing accelerator include triphenylphosphine, diphenyl(p-tolyl)phosphine, tris(alkylphenyl)phosphine, tris(alkoxyphenyl)phosphine, tris(alkyl / alkoxyphenyl)phosphine, tris(dialkylphenyl)phosphine, tris(trialkylphenyl)phosphine, tris(tetraalkylphenyl)phosphine, tris(dialkoxyphenyl)phosphine, tris(trialkoxyphenyl)phosphine, tris(tetraalkoxyphenyl)phosphine, trialkylphosphine, Examples of the organic phosphines include organic phosphines such as phosphine, dialkylarylphosphine, and alkyldiarylphosphine; complexes of these organic phosphines with organic borons; and compounds obtained by adding these organic phosphines to quinone compounds such as maleic anhydride, 1,4-benzoquinone, 2,5-toluquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl-1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, and phenyl-1,4-benzoquinone; and compounds such as diazophenylmethane.

[0150] Among the curing accelerators listed above, organic phosphines and phosphonium salts are preferred, and organic phosphines are most preferred. The curing accelerators listed above may be used alone or in any combination and ratio of two or more.

[0151] The curing accelerator is preferably used in an amount of 0.1 to 20 parts by weight, more preferably 0.5 parts by weight or more, even more preferably 1 part by weight or more, and more preferably 15 parts by weight or less, and even more preferably 10 parts by weight or less, relative to 100 parts by weight of all epoxy resin components in the epoxy resin composition (B). When the content of the curing accelerator is equal to or greater than the above-mentioned lower limit, a good curing acceleration effect can be obtained. When the content of the curing accelerator is equal to or less than the above-mentioned upper limit, it is preferable because the desired cured physical properties can be easily obtained.

[0152] [Inorganic Filler] The epoxy resin composition (B) of this embodiment can contain an inorganic filler. Examples of inorganic fillers include fused silica, crystalline silica, glass powder, alumina, calcium carbonate, calcium sulfate, talc, boron nitride, etc. These may be used alone or in any combination of two or more in any blending ratio. Among these, crushed and / or spherical fused and / or crystalline silica powder fillers are preferred for use in semiconductor encapsulation.

[0153] By using the inorganic filler, when the epoxy resin composition (B) is used as a semiconductor encapsulant, the thermal expansion coefficient of the semiconductor encapsulant can be made closer to that of the silicon chip or lead frame inside, and the amount of water absorption of the entire semiconductor encapsulant can be reduced, thereby improving the solder crack resistance.

[0154] The average particle size of the inorganic filler is usually 1 to 50 μm, preferably 1.5 to 40 μm, and more preferably 2 to 30 μm. When the average particle size is equal to or greater than the lower limit, the melt viscosity does not become too high and the flowability is not easily reduced, which is preferable. When the average particle size of the inorganic filler is equal to or less than the upper limit, the filler is less likely to clog narrow gaps in the mold during molding, which is preferable because the filler is less likely to clog narrow gaps in the mold during molding, which makes it easier to improve the filling ability of the material.

[0155] When an inorganic filler is used in the epoxy resin composition (B) of this embodiment, the inorganic filler is preferably blended in an amount of 60 to 95 mass % of the total epoxy resin composition.

[0156] [Mold Release Agent] The epoxy resin composition (B) of this embodiment can be blended with a mold release agent. Examples of mold release agents that can be used include natural waxes such as carnauba wax, synthetic waxes such as polyethylene wax, higher fatty acids such as stearic acid and zinc stearate and their metal salts, and hydrocarbon-based mold release agents such as paraffin. These may be used alone or in any combination of two or more in any blending ratio.

[0157] When a release agent is blended into the epoxy resin composition (B) of this embodiment, the blending amount of the release agent is preferably 0.1 to 5.0 parts by mass, more preferably 0.5 to 3.0 parts by mass, per 100 parts by mass of all epoxy resin components in the epoxy resin composition (B). When the blending amount of the release agent is within the above range, it is possible to exhibit good release properties while maintaining the curing characteristics of the epoxy resin composition (B), which is preferable.

[0158] [Coupling Agent] A coupling agent is preferably blended into the epoxy resin composition (B) of this embodiment. The coupling agent is preferably used in combination with an inorganic filler. By blending a coupling agent, it is possible to improve the adhesion between the epoxy resin matrix and the inorganic filler. Examples of the coupling agent include a silane coupling agent and a titanate coupling agent.

[0159] Examples of the silane coupling agent include epoxy silanes such as γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane; amino silanes such as γ-aminopropyltriethoxysilane, N-β(aminoethyl)γ-aminopropyltrimethoxysilane, N-β(aminoethyl)γ-aminopropylmethyldimethoxysilane, γ-aminopropyltrimethoxysilane, and γ-ureidopropyltriethoxysilane; mercapto silanes such as 3-mercaptopropyltrimethoxysilane; vinyl silanes such as p-styryltrimethoxysilane, vinyltrichlorosilane, vinyltris(β-methoxyethoxy)silane, vinyltrimethoxysilane, vinyltriethoxysilane, and γ-methacryloxypropyltrimethoxysilane; and polymeric epoxy, amino, and vinyl silanes.

[0160] Examples of titanate coupling agents include isopropyl triisostearoyl titanate, isopropyl tri(N-aminoethyl aminoethyl) titanate, diisopropyl bis(dioctyl phosphate) titanate, tetraisopropyl bis(dioctyl phosphite) titanate, tetraoctyl bis(ditridecyl phosphite) titanate, tetra(2,2-diallyloxymethyl-1-butyl)bis(ditridecyl)phosphite titanate, bis(dioctyl pyrophosphate)oxyacetate titanate, and bis(dioctyl pyrophosphate)ethylene titanate.

[0161] These coupling agents may be used either alone or as a mixture of two or more kinds in any combination and ratio.

[0162] When a coupling agent is used in the epoxy resin composition (B) of this embodiment, the amount thereof is preferably 0.1 to 3.0 parts by mass per 100 parts by mass of the total epoxy resin components. When the amount of the coupling agent is equal to or greater than the above lower limit, the effect of adding the coupling agent in improving the adhesion between the epoxy resin matrix and the inorganic filler tends to be enhanced. When the amount of the coupling agent is equal to or less than the above upper limit, the coupling agent is less likely to bleed out from the resulting cured product, which is preferable.

[0163] [Other Compounding Components] Components other than those described above (sometimes referred to as "other compounding components" in the present invention) can be compounded in the epoxy resin composition (B) of this embodiment. Examples of other compounding components include flame retardants, plasticizers, reactive diluents, pigments, etc. These can be appropriately compounded as needed. Components other than those listed above may be compounded in the epoxy resin composition (B) of this embodiment.

[0164] Examples of the flame retardant used in the epoxy resin composition (B) of this embodiment include halogen-based flame retardants such as brominated epoxy resins and brominated phenol resins, antimony compounds such as antimony trioxide, phosphorus-based flame retardants such as red phosphorus, phosphate esters and phosphines, nitrogen-based flame retardants such as melamine derivatives, and inorganic flame retardants such as aluminum hydroxide and magnesium hydroxide.

[0165] The method for curing the epoxy resin composition (B) of this embodiment is not particularly limited. Typically, a cured product can be obtained by a thermosetting reaction caused by heating. During the thermosetting reaction, it is preferable to select the curing temperature appropriately depending on the type of curing agent used. For example, when a phenolic curing agent is used, the curing temperature is typically 130 to 300°C. The curing temperature can also be lowered by adding a curing accelerator to these curing agents. The reaction time is preferably 1 to 20 hours, more preferably 2 to 18 hours, and even more preferably 3 to 15 hours. A reaction time of at least the lower limit is preferred because the curing reaction tends to proceed more efficiently. A reaction time of not more than the upper limit is preferred because it is easier to reduce deterioration due to heating and energy loss during heating.

[0166] [Uses] A cured product using the curable resin composition (B) of this embodiment has low water absorption and is excellent as an electronic material in terms of heat crack resistance during molding and electrical reliability when used for a long period of time.

[0167] Therefore, the curable resin composition (B) of this embodiment and its cured product can be effectively used in any application where these physical properties are required.For example, it can be suitably used in the coating field such as optical materials, automotive paints such as electrodeposition paints for automobiles, heavy-duty anticorrosion paints for ships and bridges, and paints for coating the inside of beverage cans; in the electrical and electronic field such as composite materials, laminates, semiconductor sealants, liquid insulating sealants, insulating powder paints, and coil impregnation; in the civil engineering, construction, and adhesive fields such as earthquake-resistant reinforcement of bridges, concrete reinforcement, building flooring materials, water facility linings, drainage and permeable pavements, and adhesives for structures, vehicles, and aircraft.Among these, it is particularly useful for electrical and electronic parts.

[0168] The epoxy resin composition (B) of the present embodiment may be used for the above-mentioned applications after being cured, or may be cured during the production process for the above-mentioned applications.

[0169] [Laminated Plate] Examples of a method for producing a laminated plate using the curable resin composition (B) of the present embodiment include a method for producing a laminated plate by heating and pressurizing a laminate containing a prepreg in which a fibrous substrate is impregnated with the resin varnish comprising the curable resin composition (B) of the present embodiment to cure the laminated plate.

[0170] More specifically, a fibrous substrate is impregnated with the resin varnish, dried, and the solvent is removed to form a prepreg. This prepreg is then laminated with other substrates as needed to form a laminate, which is then cured under heat and pressure to obtain a laminated board.

[0171] The number of prepreg layers in the laminate may be one or more. The laminate may also include a substrate other than the prepreg. Examples of the substrate include a metal foil such as a copper foil.

[0172] Examples of fibers constituting the fibrous substrate include inorganic fibers such as glass fibers, carbon fibers, ceramic fibers, and stainless steel fibers; natural fibers such as cotton, hemp, and paper; and synthetic organic fibers such as polyester resins and polyamide resins. Any one of these fibers may be used alone, or two or more types may be used in combination.

[0173] The shape of the fibrous substrate is not particularly limited, and examples thereof include staple fibers, yarns, mats, sheets, and the like.

[0174] The amount of resin varnish to be impregnated into the fibrous substrate is not particularly limited, and for example, the amount of solid content of the resin varnish to be impregnated is set to about 30 to 50 mass % relative to the fibrous substrate (100 mass %). The heating temperature when heating and pressurizing the laminate is preferably the above-mentioned curing temperature. The pressure condition is 2 to 20 kN / m ２ is preferred.

[0175] The laminate thus manufactured includes a fiber-reinforced resin layer containing a fibrous substrate and a cured resin varnish. The number of fiber-reinforced resin layers included in the laminate may be one or two or more. As described above, the laminate may also include a metal foil layer such as a copper foil.

[0176] [Encapsulant] When the curable resin composition (B) of the present embodiment is used as an encapsulant, the shape of the encapsulant to which the curable resin composition of the present embodiment is applied is not particularly limited, and for example, a shape similar to that employed in known semiconductors, etc. Examples of a method for forming an encapsulant using the curable resin composition (B) of the present embodiment include methods for encapsulating a semiconductor using, for example, transfer molding, compression molding, etc.

[0177] The present invention will be described in more detail below with reference to examples. The present invention is not limited to the following examples. The values ​​of various production conditions and evaluation results in the following examples represent preferred upper or lower limit values ​​in the embodiments of the present invention, and a preferred range may be defined by a combination of the above-mentioned upper or lower limit values ​​and the values ​​in the following examples or values ​​between the examples.

[0178] [Raw materials used, etc.] The structural formulae of the raw materials, reaction products, etc. used in the following examples and comparative examples are as follows.

[0179]

[0180] [Measurement and Evaluation Methods] The methods for measuring and evaluating the physical properties of the epoxy resins (epoxy resin compositions) and their cured products obtained in the following examples and comparative examples are as follows.

[0181] [Epoxy Resin Composition] <Epoxy Equivalent> This is defined as "the mass of an epoxy resin containing one equivalent of epoxy groups" and was measured in accordance with JIS K7236.

[0182] <Composition of Epoxy Resin Composition> The content ratios of the epoxy resins (3-1), (4-1), and (5-1) in the epoxy resin composition were determined by performing LC analysis using the following apparatus and conditions in accordance with JIS K0124, and calculating the ratios (mass%) by dividing the area % of each area in the LC chart represented by the epoxy resin (3-1), the epoxy resins (4-1), (5-1), and other components by the total area % of the epoxy resin (3-1), the epoxy resins (4-1), (5-1), and other components. Apparatus: Waters high-performance liquid chromatography Waters 2690 Column: Tosoh TSKgel ODS-120A (column dimensions 4.6 mm ID x 15 cm) Eluent: Gradient analysis of acetonitrile / water = 30 / 70 to 100 / 0 in 60 minutes Flow rate: 1 mL / min Detector: UV (280 nm) Temperature: 35°C Sample concentration: 0.1% Injection amount: 10 μL Peak area analysis software: Waters Empower2

[0183] <Amount of Hydrolyzable Chlorine> 0.5 g of epoxy resin was dissolved in 20 mL of dioxane, refluxed with 5 mL of 1N KOH / ethanol solution for 30 minutes, and then titrated with 0.01N silver nitrate solution to determine the amount of hydrolyzable chlorine.

[0184] <Melting point> The melting point was measured using a differential scanning calorimeter manufactured by Epson Corporation. The temperature at the top of the exothermic peak when a 5 mg sample was heated at a rate of 10°C / min was used as the melting point.

[0185] <Crystallization time> 20 g of the epoxy resin composition was weighed onto an aluminum dish and melted by heating at 130°C for 1 hour in a Safebend dryer (manufactured by Safebend Dryer Co., Ltd.). The dish was removed from the Safebend dryer and placed at room temperature. The time until crystals precipitated in three places was recorded and used as the crystallization time.

[0186] [Cured Product] <Glass Transition Temperature Tg (tan δ) and Storage Modulus E' (250°C)> The cured product was cut into a specimen measuring 5 cm in length, 1 cm in width and 4 mm in thickness, and dynamic mechanical analysis (DMA) was performed using the obtained specimen to measure Tg (tan δ) and the storage modulus at 250°C (E') under the following conditions: Analytical device: EXSTAR6100 manufactured by Seiko Instruments Inc. Measurement mode: 3-point bending mode Measurement temperature range: 30°C to 280°C Heating rate: 5°C / min Heating rate: 5°C / min *The temperature at the peak top of tan δ was taken as Tg (tan δ).

[0187] <Water Absorption Test> Test pieces were prepared by cutting the cured product into pieces 2 cm long, 2 cm wide, and 4 mm thick. These were then left in a thermo-hygrostat (Nagano Science Co., Ltd., "LH21-11P") in an atmosphere of 85°C / 85% RH for 24 hours, and the water absorption of the cured product was calculated from the masses of the test pieces before and after water absorption using the following formula: Water absorption (%) = {(mass of test piece after water supply - mass of test piece before water supply) / (mass of test piece before water supply)} × 100

[0188] [Production and Evaluation of Epoxy Resin (Epoxy Resin Composition (A))] [Example 1] A 5 L four-neck flask equipped with a thermometer, a stirrer, and a condenser was charged with 200 g of raw material phenol (2-1): tetramethylbiphenol (manufactured by Mitsubishi Chemical Corporation), 1071 g of epichlorohydrin, 5.4 g of compound (1-1), 417 g of isopropyl alcohol, and 150 g of water. The mixture was heated to 40°C to dissolve uniformly, and then 159 g of a 48.5 mass% aqueous sodium hydroxide solution was added dropwise over 90 minutes. Simultaneously with the dropwise addition, the temperature was raised from 40°C to 65°C over 90 minutes. The mixture was then maintained at 65°C for 30 minutes to complete the reaction. The reaction solution was then transferred to a 5 L separatory funnel, 300 g of 65°C hot water was added, the mixture was cooled to 65°C, and the mixture was allowed to stand for 1 hour. After standing, the aqueous layer was extracted from the separated oil and water layers, and by-product salts and excess sodium hydroxide were removed. Thereafter, epichlorohydrin was completely removed under reduced pressure at 150°C.

[0189] Subsequently, 439 g of methyl isobutyl ketone was charged, and the mixture was heated to 65°C to dissolve uniformly. Then, 6.2 g of a 48.5 mass% aqueous sodium hydroxide solution was charged, and the mixture was allowed to react for 60 minutes. The mixture was then washed four times with 400 g of water. The methyl isobutyl ketone was then completely removed under reduced pressure at 150°C to obtain the epoxy resin composition of Example 1. The epoxy equivalent (g / eq), the contents (%) of epoxy resins (3-1), (4-1), and (5-1), and the hydrolyzable chlorine content (ppm by mass), melting point (°C), and crystallization rate (seconds) were calculated and measured using the methods described below. The results are shown in Table 1.

[0190] The epoxy resin composition of Example 2 was obtained in the same manner as in Example 1, except that the amount of compound (1-1) charged was changed to 10.7 g, and the epoxy equivalent (g / eq), the contents (%) of epoxy resins (3-1), (4-1), and (5-1) were calculated, and the amount of hydrolyzable chlorine (ppm by mass), melting point (°C), and crystallization rate (seconds) were measured in the same manner. The results are shown in Table 1.

[0191] The epoxy resin composition of Example 3 was obtained in the same manner as in Example 1, except that the amount of compound (1-1) charged was changed to 21.4 g, and the epoxy equivalent (g / eq), the contents (%) of epoxy resins (3-1), (4-1), and (5-1) were calculated, and the amount of hydrolyzable chlorine (ppm by mass), melting point (°C), and crystallization rate (seconds) were measured in the same manner. The results are shown in Table 1.

[0192] The epoxy resin composition of Example 4 was obtained in the same manner as in Example 1, except that the amount of compound (1-1) charged was changed to 36.4 g. Similarly, the epoxy equivalent (g / eq) and the contents (%) of epoxy resins (3-1), (4-1), and (5-1) were calculated, and the amount of hydrolyzable chlorine (ppm by mass), melting point (°C), and crystallization rate (seconds) were measured. The results are shown in Table 1.

[0193] The epoxy resin composition of Example 5 was obtained in the same manner as in Example 1, except that the amount of compound (1-1) charged was changed to 53.5 g, and the epoxy equivalent (g / eq), the contents (%) of epoxy resins (3-1), (4-1), and (5-1) were calculated, and the amount of hydrolyzable chlorine (ppm by mass), melting point (°C), and crystallization rate (seconds) were measured in the same manner. The results are shown in Table 1.

[0194] The epoxy resin composition of Example 6 was obtained in the same manner as in Example 1, except that the amount of compound (1-1) charged was changed to 107 g. Similarly, the epoxy equivalent (g / eq) and the contents (%) of epoxy resins (3-1), (4-1), and (5-1) were calculated, and the amount of hydrolyzable chlorine (ppm by mass), melting point (°C), and crystallization rate (seconds) were measured. The results are shown in Table 1.

[0195] The epoxy resin composition of Example 7 was obtained in the same manner as in Example 1, except that the amounts of epichlorohydrin, compound (1-1), isopropyl alcohol, and water were changed to 765 g, 15.3 g, 297 g, and 0 g, respectively. The epoxy equivalent (g / eq), the contents (%) of epoxy resins (3-1), (4-1), and (5-1), and the amount of hydrolyzable chlorine (ppm by mass), melting point (°C), and crystallization rate (seconds) were calculated and measured in the same manner as described below. The results are shown in Table 1.

[0196] The epoxy resin composition of Comparative Example 1 was obtained in the same manner as in Example 1, except that compound (1-1) was not used, and the epoxy equivalent (g / eq), the contents (%) of epoxy resins (3-1), (4-1), and (5-1) were calculated, and the amount of hydrolyzable chlorine (ppm by mass), melting point (°C), and crystallization rate (seconds) were measured in the same manner. The results are shown in Table 1.

[0197] The epoxy resin composition of Comparative Example 2 was obtained in the same manner as in Example 7, except that compound (1-1) was not used. The epoxy equivalent (g / eq), the contents (%) of epoxy resins (3-1), (4-1), and (5-1), and the amount of hydrolyzable chlorine (ppm by mass), melting point (°C), and crystallization rate (seconds) were similarly calculated and measured. The results are shown in Table 1.

[0198] Comparative Example 3 An epoxy resin composition was obtained by the same procedure as in Comparative Example 1. The obtained epoxy resin composition was then subjected to crystallization three times in propylene glycol monomethyl ether, and the contained solvent was distilled off under reduced pressure to obtain the epoxy resin composition of Comparative Example 3. The epoxy equivalent (g / eq), the contents (%) of epoxy resins (3-1), (4-1), and (5-1) were calculated, and the amount of hydrolyzable chlorine (ppm by mass), melting point (°C), and crystallization rate (seconds) were measured in the same manner. The results are shown in Table 1.

[0199]

[0200] [Preparation and Evaluation of Cured Products] [Examples 8 to 12 and Comparative Examples 4 and 5] The epoxy resin compositions of Examples 1 to 5 and Comparative Examples 1 and 3 were blended with a curing agent (phenol novolac resin (trade name "PSM4261" manufactured by Gun-ei Chemical Co., Ltd.)) and a curing catalyst (triphenylphosphine (trade name "Hokuko TPP" manufactured by Hokko Chemical Industry Co., Ltd.)) in the proportions shown in Table 2, heated to 100°C, and stirred until homogenous, to obtain epoxy resin compositions. The resulting epoxy resin compositions were cured by heating at 120°C for 2 hours and at 175°C for 6 hours to obtain cured products. The Tg and storage modulus of the obtained cured products were measured, and a water absorption test was performed. The results are shown in Table 2. In Table 2, "parts" means "parts by mass."

[0201]

[0202] [Evaluation of Results] Examples 1 to 7 demonstrated that the content of epoxy resin (4) or (5) in an epoxy resin composition can be controlled by the amount of compound (1) (compound (6)) relative to epichlorohydrin during the reaction. Controlling the content of compound (1) (compound (6)) during the reaction can produce an epoxy resin that flows at low temperatures. Furthermore, the results of Examples 8 to 12 demonstrated that when the content of epoxy resin (4) or (5) in an epoxy resin composition is controlled within a certain range, the resulting cured product exhibits low storage modulus and low water absorption. These results demonstrate that epoxy resin compositions containing epoxy resin (4) or (5) in a specified proportion offer high production efficiency during epoxy resin composition production, low environmental impact during semiconductor production, and potential as raw materials for highly reliable electronic materials in terms of heat resistance, durability, mechanical properties, and water absorption.

Claims

1. A method for producing an epoxy resin by reacting a raw material phenol compound or a raw material amine compound with epihalohydrin, characterized in that the reaction is carried out in the presence of a compound represented by the following formula (1). 【Chemical 1】 (In the above formula (1), R １ represents an aliphatic hydrocarbon group having 2 to 8 carbon atoms.)

2. The method for producing an epoxy resin according to Claim 1, wherein the amount of the compound represented by the formula (1) is 0.01 to 19% by mass based on the epihalohydrin.

3. The method for producing an epoxy resin according to Claim 1, wherein the raw material phenol compound is represented by the following formula (2), and the epoxy resin contains an epoxy compound represented by the following formula (3). [Chemical Formula 2] (In the above formulas (2) and (3), X １ is a divalent hydrocarbon group having 1 to 13 carbon atoms, -O-, -S-, -SO ２ -, -C(CF ３ ) ２ -, and -CO-, or a direct bond, and R ２ to R １３ are each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or an alkynyl group having 2 to 12 carbon atoms. n represents an integer of 0 to 10.)

4. The method for producing an epoxy resin according to Claim 1, wherein the epoxy resin contains an epoxy compound represented by the following formula (4). [Chemical Formula 3] (In the above formula (4), X １ , R ２ to R １３ , n have the same meanings as those in formulas (2) and (3), and R １ has the same meaning as that in formula (1).)

5. An epoxy resin composition (A) containing 80.0 to 99.9% by mass of an epoxy compound represented by the following formula (3) and 0.1 to 8.0% by mass of an epoxy compound represented by the following formula (5). 【Chemical Formula 4】 (In the above formulas (3) and (5), X １ is a divalent hydrocarbon group having 1 to 13 carbon atoms, -O-, -S-, -SO ２ -, -C(CF ３ ) ２ -, and -CO-, or a direct bond, and R ２ to R １３ are each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or an alkynyl group having 2 to 12 carbon atoms. n represents an integer of 0 to 10. R １４ is a non-linear aliphatic hydrocarbon group having 3 to 8 carbon atoms.)

6. The epoxy resin composition (A) according to Claim 5, having a hydrolyzable chlorine content of 1000 ppm by mass or less.

7. An epoxy resin composition (B) containing the epoxy resin composition (A) according to Claim 5 and containing 0.01 to 1000 parts by mass of a curing agent per 100 parts by mass of the epoxy resin composition (A).

8. The epoxy resin composition (B) according to Claim 7, wherein the curing agent is at least one selected from the group consisting of a phenolic curing agent, an amine curing agent, an acid anhydride curing agent, and an amide curing agent.

9. A cured product obtained by curing the epoxy resin composition (B) according to Claim 7 or 8.

10. An electric and electronic part obtained by curing the epoxy resin composition (B) according to Claim 7 or 8.

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