WO2014010559A1

WO2014010559A1 - Epoxy resin, epoxy resin composition, method for curing same, and cured product thereof

Info

Publication number: WO2014010559A1
Application number: PCT/JP2013/068650
Authority: WO
Inventors: 大神　浩一郎; 健廣田; 山田　尚史; 秀安朝蔭; 梶　正史
Original assignee: 新日鉄住金化学株式会社
Priority date: 2012-07-09
Filing date: 2013-07-08
Publication date: 2014-01-16
Also published as: TW201418308A; JPWO2014010559A1

Abstract

Provided is an epoxy resin cured product that, whether used for lamination, molding, or casting, has excellent high heat resistance, high-temperature and long-term pyrolysis stability, and fluidity, and that is useful in the sealing of electrical and electronic parts, for circuit substrate materials, and the like. Provided are: an epoxy resin containing at least 10% of a polymer represented by general formula (2), wherein n is 1 or greater; an epoxy resin composition containing the epoxy resin, a phenolic curing agent, a curing catalyst, and an inorganic filler; and a cured product thereof. Here, R is a hydrogen atom or a C_1-6 hydrocarbon group, and G is a glycidyl group.

Description

Epoxy resin, epoxy resin composition, curing method thereof and cured product

The present invention relates to an epoxy resin, an epoxy resin composition, a curing method thereof, and a cured product, which are excellent in heat resistance, thermal decomposition stability and fluidity, and excellent for sealing.

Epoxy resins have been used in a wide range of industrial applications, but their required performance has become increasingly sophisticated in recent years. Under such circumstances, in power devices that have been developed in recent years, further improvement in the power density of the devices is required. As a result, the temperature of the chip surface during operation reaches 250 ° C. It is desired to develop a sealing material that can withstand temperature.

Under such circumstances, epoxy resin compositions having a tetraphenylethane structure are known as epoxy resin compositions having excellent heat resistance. For example, Patent Document 1 discloses a tetraphenylethane type epoxy resin and many epoxy resin compositions. An epoxy resin composition containing a polyhydric phenol resin curing agent as an essential component is shown, and an epoxy resin cured product having excellent heat resistance is disclosed. Patent Document 2 discloses an epoxy resin composition excellent in heat resistance and a cured product using a tetraphenylethane type epoxy resin and an acid anhydride curing agent. However, even when the tetraphenylethane type epoxy resin is used in this way, only a cured product having a glass transition temperature of about 230 ° C. is obtained by a normal molding method, and among them, a phenol resin curing agent is used. In some cases, only a cured product having a glass transition temperature of 200 ° C. or lower is obtained. Therefore, there has been a problem that the characteristics of the sealing material for power devices with high heat resistance that can withstand an operating temperature as high as 250 ° C. cannot be satisfied.

In addition, in order to withstand actual use at high temperatures, not only the glass transition temperature, which is an indicator of heat resistance, but also the decomposition start temperature at high temperature use is important, and materials with a high decomposition start temperature as well as the glass transition temperature are required. It has been.

Japanese Patent Laid-Open No. 9-3162 JP-A-2-219812

The object of the present invention is to provide high heat resistance, high temperature and long-term thermal decomposition stability, and excellent fluidity in applications such as lamination, molding, casting, and adhesion, sealing of electrical and electronic components, circuit boards, etc. An object of the present invention is to provide a cured epoxy resin useful as a material.

The present invention relates to an epoxy resin represented by the following general formula (2).

(Wherein, R independently represents a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, G represents a glycidyl group. N is a repeating number, but n is 1 or more of a multimer of 10% or more. Including)

The present invention also includes a reaction between a polyvalent hydroxy compound represented by the following general formula (1) and having a component of n = 1 or more of 10% or more in area% measured by gel permeation chromatography and epichlorohydrin. It is related with the epoxy resin characterized by being obtained.
This epoxy resin is preferably an epoxy resin represented by the general formula (2), and preferably contains 10% or more of a multimer having n of 1 or more.

(Here, R independently represents a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, G represents a glycidyl group, and n represents a repeating number.)

Furthermore, this invention relates to the epoxy resin composition characterized by containing said epoxy resin, a phenol type hardening | curing agent, a curing catalyst, and an inorganic filler.
Here, the curing catalyst is preferably at least one selected from imidazoles, organic phosphines, or amines, and the epoxy resin composition was further measured by DSC at a temperature rising rate of 10 ° C./min. In some cases, it is preferable to exhibit a curing performance in which the heat generation peak top is 150 ° C. or higher.

The present invention also includes a method for curing the epoxy resin composition, wherein the epoxy resin composition is molded at 100 ° C. to 200 ° C. and then post-cured at 200 ° C. to 300 ° C., and the curing conditions of the curing method It relates to a cured epoxy resin obtained by curing with 1. This cured epoxy resin is suitable for a semiconductor encapsulant. Furthermore, this invention relates to the semiconductor device characterized by sealing the semiconductor element with the said epoxy resin hardened | cured material.

If the epoxy resin composition of the present invention is cured by heating, an epoxy resin cured product can be obtained. This cured product is excellent in terms of high heat resistance, high-temperature and long-term thermal decomposition stability, high fluidity, and the like. And can be suitably used for applications such as sealing of electric / electronic parts and circuit board materials.

GPC chart of the phenol resin obtained in Synthesis Example 1 GPC chart of epoxy resin obtained in Synthesis Example 2 GPC chart of the phenol resin obtained in Synthesis Example 3 GPC chart of epoxy resin obtained in Synthesis Example 4 GPC chart of phenol resin obtained in Synthesis Example 5 GPC chart of epoxy resin obtained in Synthesis Example 6 GPC chart of phenol resin obtained in Synthesis Example 7 GPC chart of epoxy resin obtained in Synthesis Example 8

Hereinafter, the present invention will be described in detail.
The epoxy resin of the present invention is represented by the above general formula (2) and can be produced by reacting a polyvalent hydroxy compound represented by the above general formula (1) with epichlorohydrin. And this polyhydric hydroxy compound can be manufactured by making phenol and glyoxal react.

In general formula (1) and general formula (2), the same symbols have the same meaning, and R independently represents a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms. Preferably, R is a hydrogen atom or alkyl having 1 to 4 carbon atoms. n is the number of repetitions and is usually a mixture of components with different n, but preferably consists of 0 to 10 components. 10% or more is preferably a multimer of n = 1 or more. The% of n is an area% measured by gel permeation chromatography (GPC), and the area% of a multimeric component having an n of 1 or more is preferably 10% or more.

Conventionally, the above-mentioned tetrafunctional polyhydroxy compound having n = 0 which is generally produced has been obtained by using a phenol compound in a large excess with respect to glyoxal. In the reaction between the phenol compound and glyoxal, the amount of the phenol compound used relative to the glyoxal is limited, and the amount of glyoxal used is 0.02 to 0.2 mol, preferably 0.04 to 0.00. 1 mole. When the amount of glioxal used is more than 0.2 mol, the softening point of the polyvalent hydroxy compound and the epoxy resin produced therefrom is increased, which hinders the molding workability, and when it is less than 0.02 mol, n = 0. As the production increases, the amount of excess phenol after the reaction ends increases, which is not industrially preferable. The polyvalent hydroxy compound used as a raw material for the epoxy resin containing a multimer of the present invention has an area% of a multimeric component having an n of 1 or more of 10% or more. This adjusts the molar ratio of the phenol compound and glyoxal. Thus, the desired multimer content can be obtained.

In general, this reaction is carried out in the presence of a known acid catalyst such as an inorganic acid or an organic acid. Examples of such an acid catalyst include mineral acids such as hydrochloric acid, sulfuric acid, and phosphoric acid, organic acids such as formic acid, oxalic acid, trifluoroacetic acid, and p-toluenesulfonic acid, zinc chloride, aluminum chloride, iron chloride, Examples include Lewis acids such as boron trifluoride and solid acids such as activated clay, silica-alumina, and zeolite.

• This reaction is usually carried out at 10 to 250 ° C. for 1 to 20 hours. Further, as a solvent during the reaction, for example, alcohols such as methanol, ethanol, propanol, butanol, ethylene glycol, methyl cellosolve, ethyl cellosolve, diglyme and triglyme, and aromatic compounds such as benzene, toluene, chlorobenzene and dichlorobenzene It is good to use. In particular, ethyl cellosolve, diglyme and triglyme are preferable from the viewpoint of solubility. After completion of the reaction, the obtained polyvalent hydroxy resin may be removed by a method such as distillation under reduced pressure, washing with water or reprecipitation in a poor solvent, but as a raw material for the epoxidation reaction while leaving the solvent. It may be used.

The polyvalent hydroxy compound produced in this way is represented by the above general formula (1), and the component of n = 1 or more in area% measured by GPC is 10% or more, preferably 11% or more. More preferably, it is 12% or more. Moreover, since the viscosity of the epoxy resin obtained by using this increases when the ratio of a multimer increases and a moldability falls, the component of n = 1 or more is preferable 60% or less, 50% or less, especially 40 % Or less is preferable. The average number of repetitions n (number average) is 0 to 5, but is adjusted so as to include 10% or more of components where n = 1 or more. Therefore, n is approximately 0.10 or more.

エポキシ The epoxy resin of the present invention is an epoxy resin mainly composed of a tetrafunctional epoxy compound having n = 0 components in a multimeric mixture represented by the general formula (2). In the case of using a polyvalent hydroxy compound containing 10% or more of n = 1 or more as a raw material, there is no change in n except in the case where an unreacted substance remains in the epoxidation step. Can be thought of as a rate. The epoxy resin of the present invention contains a multimeric component bonded with a methine chain, so the principle is not clear, but it is expected that the crosslinks will be relatively dense, and as a result, the thermal decomposition stability is excellent. It is considered a thing.

That is, in the epoxy resin of the general formula (2), when the ratio of the n = 0 (tetrafunctional) component is increased, the ethylene unit and the phenyl glycidyl ether unit are infinitely close to 1: 4. On the other hand, when a polyvalent hydroxy compound having a higher ratio of n = 1 (7 functional) and n = 2 (10 functional) components, which are more multifunctional components, is used, the ratio is 2: 7 and 3:10, It is considered that an excellent cured product which is thermally stable can be obtained when the crosslink density becomes denser and glycidyl ether units are relatively reduced. In addition, when the polyfunctional component is increased, it is considered that the cured product having more excellent thermal stability is obtained by increasing the crosslinking density of the cured product even in the reaction with the curing agent. However, when the component increases by n = 5 or more, the molecular weight increases, so that the fluidity and molding processability tend to be inferior. For this reason, n is a number in the range of 0 to 10, preferably includes n = 0, and the average (number average) of n is preferably in the range of 0.1 to 4. Since n inherits n of the polyvalent hydroxy compound used as a raw material almost as it is, adjustment of n is made by adjusting n of the polyvalent hydroxy compound.

The epoxy resin of the present invention can be produced by reacting the polyvalent hydroxy resin with epichlorohydrin. This reaction can be performed in the same manner as a normal epoxidation reaction. For example, after dissolving a polyvalent hydroxy resin in excess epichlorohydrin, the reaction is carried out at 50 to 150 ° C., preferably 60 to 120 ° C. for 1 to 10 hours in the presence of an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide. The method of letting it be mentioned. At this time, the amount of the alkali metal hydroxide used is 0.8 to 1.2 mol, preferably 0.9 to 1.0 mol, based on 1 mol of the hydroxyl group in the polyvalent hydroxy compound. Epichlorohydrin is used in excess with respect to the hydroxyl group in the polyvalent hydroxy resin, but is usually 1.5 to 15 mol, preferably 2 to 8 mol, based on 1 mol of the hydroxyl group in the polyvalent hydroxy compound. After completion of the reaction, excess epichlorohydrin is distilled off, the residue is dissolved in a solvent such as toluene, methyl isobutyl ketone, filtered, washed with water to remove inorganic salts, and then the solvent is distilled off to give a general formula. The epoxy resin represented by (2) can be obtained. However, since the reaction of the glycidyl group and the unreacted phenolic hydroxyl group also proceeds during the epoxidation reaction, and a multimer linked by the glycidyl group is generated, it is necessary to adjust the reaction conditions within the above range. Although it is the same in terms of a multimer of tetrafunctional epoxy compounds, the heat resistance is greatly different depending on the bonding site.

The viscosity and softening point of the epoxy resin can be easily adjusted by changing the molar ratio of the phenolic compound and glyoxal when synthesizing the polyvalent hydroxy resin that is the raw material of the epoxy resin. From this viewpoint, the viscosity at 150 ° C. is preferably 3.0 Pa · s or less, more preferably 1.0 Pa · s or less, and still more preferably 0.5 Pa · s or less. Moreover, it is preferable that the softening point shall be 130 degrees C or less.

Next, the epoxy resin composition of the present invention will be described. The epoxy resin composition of the present invention includes the epoxy resin of the present invention, a curing agent, a curing catalyst, and an inorganic filler. Here, the epoxy resin of the present invention is an epoxy resin obtained by reacting an epoxy resin represented by the general formula (2) or a polyvalent hydroxy compound represented by the general formula (1) with epichlorohydrin.

フェノール A phenolic curing agent is used as a curing agent to be blended in the epoxy resin composition. In fields where high electrical insulation is required, such as semiconductor encapsulants, polyhydric phenols are preferably used as curing agents. Below, the specific example of a hardening | curing agent is shown.

Examples of the polyhydric phenols include divalent phenols such as bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, hydroquinone, resorcin, catechol, biphenols, naphthalenediols, and tris- (4-hydroxyphenyl). ) Trivalent or higher typified by methane, 1,1,2,2-tetrakis (4-hydroxyphenyl) ethane, phenol novolak, o-cresol novolak, naphthol novolak, dicyclopentadiene type phenol resin, phenol aralkyl resin, etc. There are phenols. Furthermore, phenols, naphthols, or divalent phenols such as bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, 4,4 ′ -biphenol, 2,2 ′ -biphenol, hydroquinone, resorcin, catechol, naphthalene diols, etc. Cross-linking of formaldehyde, acetaldehyde, benzaldehyde, p-hydroxybenzaldehyde, p-xylylene glycol, p-xylylene glycol dimethyl ether, divinylbenzene, diisopropenylbenzene, dimethoxymethylbiphenyls, divinylbiphenyl, diisopropenylbiphenyls, etc. Polyphenolic compounds synthesized by reaction with chemicals, biphenyl aralkyl type pheno obtained from phenols and bischloromethylbiphenyl, etc. There is Le resin. Furthermore, naphthol aralkyl resins synthesized from naphthols and paraxylylene dichloride, polyvalent hydroxy compounds represented by the general formula (1), and the like can be given.

The blending amount of the soot curing agent is blended in consideration of the equivalent balance between the epoxy group in the epoxy resin and the hydroxyl group of the polyhydric phenol. The equivalent ratio of epoxy resin and curing agent is usually in the range of 0.2 to 5.0, preferably in the range of 0.5 to 2.0, more preferably in the range of 0.8 to 1.5. It is. If it is larger or smaller than this, the curability of the epoxy resin composition is lowered, and the heat resistance, mechanical strength and the like of the cured product are lowered.

In addition, in this epoxy resin composition, as the curing agent component, another type of curing agent may be blended in addition to the aromatic hydroxy compound. Examples of the epoxy resin in this case include dicyandiamide, acid anhydrides, aromatic and aliphatic amines. In the resin composition, one or more of these curing agents can be mixed and used. However, the amount of the curing agent other than the phenol-based curing agent is preferably 50 wt% or less of the total curing agent.

In addition, in this epoxy resin composition, as the epoxy resin component, another type of epoxy resin may be blended in addition to the epoxy resin represented by the general formula (2). As the epoxy resin in this case, all ordinary epoxy resins having two or more epoxy groups in the molecule can be used. Examples include bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, 4,4 ′ -biphenol, 3,3 ′, 5,5′-tetramethyl-4,4′-dihydroxybiphenyl, resorcin, naphthalenediols Trivalent or more epoxides of divalent phenols such as tris- (4-hydroxyphenyl) methane, 1,1,2,2-tetrakis (4-hydroxyphenyl) ethane, phenol novolak, o-cresol novolak, etc. Epoxidized products of phenols, epoxidized products of cocondensation resins obtained from dicyclopentadiene and phenols, epoxidized products of cocondensation resins obtained from cresols, formaldehyde and alkoxy-substituted naphthalenes, phenols and paraxylylene dichloride Obtained from etc. E Nord aralkyl resin epoxidized product, there phenols and bis-chloromethyl biphenyl biphenyl aralkyl type phenolic resins obtained from the epoxy compound, epoxidized naphthol aralkyl resin and the like which are synthesized from naphthols and para-xylylene dichloride and the like. These epoxy resins can be used alone or in combination of two or more. In the case of the composition comprising the epoxy resin of the present invention as an essential component, the amount of the epoxy resin represented by the general formula (2) is in the range of 5 to 100 wt%, preferably 60 to 100 wt% in the entire epoxy resin. It is good that it is.

As the inorganic filler, for example, silica powder such as spherical or crushed fused silica, crystalline silica, alumina powder, glass powder, or mica, talc, calcium carbonate, alumina, hydrated alumina, boron nitride, aluminum nitride, Examples thereof include silicon nitride, silicon carbide, titanium nitride, zinc oxide, tungsten carbide, magnesium oxide, and the preferable blending amount when used for a semiconductor sealing material is 70% by weight or more, and more preferably 80% by weight or more. .

As the soot curing catalyst, it is preferable to use a curing catalyst (high temperature active catalyst) having an active site in a high temperature region in the epoxy resin composition for the purpose of promoting curing and improving fluidity during molding.

The content of the soot curing catalyst is in the range of 0.2 to 5 parts by weight with respect to 100 parts by weight of the epoxy resin. The amount is preferably 0.5 to 3 parts by weight, more preferably 0.5 to 2.5 parts by weight. If it is smaller than this, the curability will be lowered, and conversely if it is larger than this, the fluidity improving effect at the time of molding will not be sufficiently exhibited.

The DSC exothermic peak temperature of the epoxy resin composition using a high temperature active catalyst is 150 ° C. or higher, preferably 155 ° C. or higher, more preferably 165 ° C. or higher. When the exothermic peak temperature is lower than 150 ° C., the curing reaction proceeds at the time of molding, and the effect of improving fluidity is not sufficiently exhibited. This DSC exothermic peak temperature is a temperature showing a maximum exothermic peak when an epoxy resin composition containing a high temperature active catalyst as a curing catalyst is subjected to DSC measurement under a temperature rising rate of 10 ° C./min.

Examples of the curing catalyst or the high temperature active catalyst include imidazoles, organic phosphines, amines and the like. Examples of imidazoles include 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-heptadecylimidazole, and 2,4-diamino-6- [2′-dimethyl. Imidazolyl- (1 ′)]-ethyl-s-triazine, 2,4-diamino-6- [2′-ethyl-4′-methylimidazolyl- (1 ′)]-ethyl-s-triazine, 2,4- Examples of organic phosphines such as diamino-6- [2′-undecylimidazolyl- (1 ′)]-ethyl-s-triazine include tris- (2,6-dimethoxyphenyl) phosphine, tri-p-tolylphosphine, Examples of amines such as tris (p-chlorophenyl) phosphine and tris (p-methoxyphenyl) phosphine include 1,8-diazabicyclo. And phenol novolak salt of (5,4,0) undecene-7. The addition amount is usually in the range of 0.2 to 5 parts by weight with respect to 100 parts by weight of the epoxy resin.

In the present invention, by using a high-temperature active catalyst having a specific active temperature region as a curing catalyst, it is possible to suppress a decrease in fluidity. Further, regarding the curing conditions, particularly when the epoxy resin of the present invention is used. In addition, it has been found that the curing conditions at high temperature greatly affect the glass transition temperature.

The resin composition of the present invention may further include a release agent such as carnauba wax or OP wax, a coupling agent such as 4-aminopropylethoxysilane or γ-glycidoxypropyltrimethoxysilane, carbon black, if necessary. And the like, flame retardants such as antimony trioxide, and lubricants such as calcium stearate.

In the epoxy resin composition of the present invention, an oligomer or a polymer compound such as polyester, polyamide, polyimide, polyether, polyurethane, petroleum resin, indene resin, indene-coumarone resin, phenoxy resin, etc. is used as another modifier. You may mix | blend suitably. The addition amount is usually in the range of 2 to 30 parts by weight with respect to 100 parts by weight of the epoxy resin.

In addition, the epoxy resin composition of the present invention may contain additives such as pigments, retardants, thixotropic agents, coupling agents, fluidity improvers, and antioxidants.

Examples of the soot pigment include organic or inorganic extender pigments and scaly pigments. Examples of the thixotropic agent include silicon-based, castor oil-based, aliphatic amide wax, polyethylene oxide wax, and organic bentonite.

The epoxy resin composition of the present invention is made into a varnish in which an organic solvent is dissolved, and then impregnated into a fibrous material such as glass cloth, aramid nonwoven fabric, polyester nonwoven fabric such as liquid crystal polymer, and the like, and then the solvent is removed. It can be. Moreover, it can be set as a laminated body by apply | coating on sheet-like materials, such as copper foil, stainless steel foil, a polyimide film, and a polyester film depending on the case.

Any method may be used for preparing the epoxy resin composition of the present invention as long as various raw materials can be uniformly dispersed and mixed. As a general method, raw materials of a predetermined blending amount are sufficiently mixed by a mixer or the like. Then, a method of melt-kneading with a mixing roll, an extruder or the like, cooling, and pulverizing can be mentioned.

エポキシ The epoxy resin composition of the present invention and its cured product are particularly suitable for sealing semiconductor devices.

硬化 The cured product of the present invention can be obtained by thermally curing the epoxy resin composition. In order to obtain a cured product using the epoxy resin composition of the present invention, for example, methods such as transfer molding, press molding, cast molding, injection molding, and extrusion molding are applied, but from the viewpoint of mass productivity. Transfer molding is preferred.

The curing method of the epoxy resin composition of the present invention is 100 ° C. to 200 ° C., preferably 120 ° C. to 190 ° C., more preferably 150 to 180 ° C., and then 200 ° C. to 300 ° C., preferably 220 ° C. to 280 ° C. More preferably, it is produced by post-curing at 230 to 270 ° C., and a cured product excellent in terms of high heat resistance, high-temperature long-term thermal decomposition stability, high fluidity and the like can be obtained.
The molding time is preferably 1 to 60 minutes, more preferably 1 to 10 minutes. If the molding time is long, the productivity will be poor, and if it is too short, it will be difficult to release. The post cure time is preferably 10 minutes to 10 hours, more preferably 30 minutes to 8 hours, and particularly preferably 2 hours to 6 hours. When the post-cure time is short, curing does not proceed sufficiently, and sufficient characteristics such as heat resistance and mechanical properties cannot be obtained. Moreover, productivity will fall when it exceeds 10 hours.

In the epoxy resin composition of the present invention, the curing reaction proceeds even in a high post-cure temperature region where a general epoxy resin composition cannot react, and has a very high heat resistance, heat decomposition resistance, mechanical properties, etc. You can get things.

Hereinafter, the present invention will be described in detail based on synthesis examples, examples, and comparative examples.

Synthesis example 1
A 5 L 4-neck flask was charged with 3500 g (37.2 mol) of phenol and 2.36 g of p-toluenesulfonic acid as an acid catalyst, and the temperature was raised to 50 ° C. Next, while stirring at 50 ° C., 360 g of a 40% aqueous solution of glyoxal was added dropwise over 30 minutes. After completion of the addition, the reaction was carried out at 50 ° C. for 30 minutes and at 100 ° C. for 2 hours. Subsequently, dehydration was performed at 100 ° C. under reduced pressure, and the reaction was performed at 100 ° C. for 4 hours. After completion of the reaction, phenol was distilled off to obtain 711 g of phenol resin. The obtained resin had a hydroxyl equivalent weight of 119.4 g / eq. Met. From the GPC measurement results, n = 0 component: 71.5% and n = 1 or more: 13.2%.

Synthesis example 2
A 5 L 4-neck flask was charged with 500 g of the phenol resin obtained in Synthesis Example 1, 377 g of diethylene glycol dimethyl ether, and 2511 g of epichlorohydrin, and the temperature was raised to 60 ° C. Subsequently, 48.2 g of a 49% aqueous potassium hydroxide solution was added dropwise over 2 hours to perform a preliminary reaction, and 298.9 g of a 49% aqueous sodium hydroxide solution was added dropwise over 3.5 hours at 63 ° C. under reduced pressure. The water refluxed during the dropwise addition and epichlorohydrin were separated in a separation tank, the epichlorohydrin was returned to the reaction vessel, and water was removed from the system to react. After completion of the reaction, the salt produced by filtration was removed, and after further washing with water, epichlorohydrin was distilled off to obtain 660 g of epoxy resin (epoxy resin A). The epoxy equivalent of the obtained resin was 182.0 g / eq. The melt viscosity at 150 ° C. was 0.35 Pa · s.

Synthesis example 3
A 3 L 4-neck flask was charged with 1000 g of phenol, 232 g of 40 wt% aqueous glyoxal solution and 125 g of acetone, and 187.5 g of 95 wt% sulfuric acid was added dropwise over 2 hours. Thereafter, the reaction was carried out at 40 ° C. for 12 hours, and after completion of the reaction, the mixture was cooled to 15 ° C. and neutralized. Subsequently, 632 g of acetone was added, and the precipitate was filtered off. Further, the mixture was washed with a mixed solution of acetone and water, charged with 1400 g of methanol, dissolved by heating under reflux for about 1 hour, and then filtered while hot to remove neutralized salts. On the other hand, the obtained methanol solution was added with 564 g of water under stirring, and then distilled under reduced pressure to distill off methanol. Thereafter, the mixture was stirred overnight at 15 ° C., separated by filtration, and dried under reduced pressure at about 130 ° C. to obtain 227 g of tetrakisphenolethane as white crystals. The resulting resin had a hydroxyl equivalent weight of 103.8 g / eq. Met. From the GPC measurement results, n = 0 component: 100%.

Synthesis example 4
A 5 L 4-neck flask was charged with 500 g of the phenol resin obtained in Synthesis Example 3, 434 g of diethylene glycol dimethyl ether, and 2896 g of epichlorohydrin, and the temperature was raised to 60 ° C. Subsequently, 55.5 g of 49% aqueous potassium hydroxide solution was added dropwise over 2 hours to perform a preliminary reaction, and then 344.6 g of 49% aqueous sodium hydroxide solution was added dropwise over 3.5 hours at 63 ° C. under reduced pressure. The water refluxed during the dropwise addition and epichlorohydrin were separated in a separation tank, the epichlorohydrin was returned to the reaction vessel, and water was removed from the system to react. After completion of the reaction, the salt produced by filtration was removed, and after further washing with water, epichlorohydrin was distilled off to obtain 693 g of epoxy resin (epoxy resin B). The epoxy equivalent of the obtained resin was 173.0 g / eq. DSC confirmed that the crystalline resin had a melting point of 181 ° C.

Synthesis example 5
A 5 L 4-necked flask was charged with 3500 g (37.2 mol) of phenol and 1.77 g of p-toluenesulfonic acid as an acid catalyst, and the temperature was raised to 50 ° C. Next, 270 g of 40% aqueous glyoxal aqueous solution was added dropwise over 30 minutes while stirring at 50 ° C., and reacted at 50 ° C. for 1 hour and at 60 ° C. for 2.5 hours. Subsequently, dehydration was performed at 60 ° C. under reduced pressure, and the reaction was performed at 60 ° C. for 8.5 hours. After completion of the reaction, phenol was distilled off to obtain 534 g of phenol resin. The resulting resin had a hydroxyl equivalent weight of 112.0 g / eq. Met. From the GPC measurement results, n = 0 component: 79.3% and n = 1 or more component: 8.6%.

Synthesis Example 6
A 5 L 4-neck flask was charged with 500 g of the phenol resin obtained in Synthesis Example 5, 403 g of diethylene glycol dimethyl ether, and 2684 g of epichlorohydrin, and the temperature was raised to 60 ° C. Subsequently, after 51.5 g of 49% aqueous potassium hydroxide solution was added dropwise over 2 hours to perform a preliminary reaction, 315.3 g of 49% aqueous sodium hydroxide solution was added dropwise over 3.5 hours at 63 ° C. under reduced pressure. The water refluxed during the dropwise addition and epichlorohydrin were separated in a separation tank, epichlorohydrin was returned to the reaction vessel, and water was removed from the system to react. After completion of the reaction, the salt generated by filtration was removed, and after further washing with water, epichlorohydrin was distilled off to obtain 675 g of an epoxy resin (epoxy resin D). The epoxy equivalent of the obtained resin was 179.5 g / eq. The melt viscosity at 150 ° C. was 0.28 Pa · s.

Synthesis example 7
A 5 L 4-necked flask was charged with 300 g of phenol (3.2 mol) and 1.01 g of p-toluenesulfonic acid as an acid catalyst, and the temperature was raised to 50 ° C. Next, 154 g of 40% aqueous glyoxal solution was added dropwise over 30 minutes while stirring at 50 ° C., and reacted at 50 ° C. for 30 minutes and at 100 ° C. for 2 hours. Subsequently, dehydration was performed at 100 ° C. under reduced pressure, and the reaction was performed at 100 ° C. for 4 hours. After completion of the reaction, phenol was distilled off to obtain 226 g of phenol resin. The obtained resin had a hydroxyl equivalent weight of 130.6 g / eq. Met. From the GPC measurement results, n = 0 component: 29.9%, and n = 1 or more component: 55.3%.

Synthesis example 8
A 5 L 4-neck flask was charged with 125 g of the phenol resin obtained in Synthesis Example 7, 86 g of diethylene glycol dimethyl ether, and 575 g of epichlorohydrin, and the temperature was raised to 60 ° C. Subsequently, 11.0 g of 49% aqueous potassium hydroxide solution was added dropwise over 2 hours to perform a preliminary reaction, and then 67.5 g of 49% aqueous sodium hydroxide solution was added dropwise over 3.5 hours at 63 ° C. under reduced pressure. The water refluxed during the dropwise addition and epichlorohydrin were separated in a separation tank, the epichlorohydrin was returned to the reaction vessel, and water was removed from the system to react. After completion of the reaction, the salt produced by filtration was removed, and after further washing with water, epichlorohydrin was distilled off to obtain 70 g of an epoxy resin (epoxy resin E). The epoxy equivalent of the obtained resin was 209.6 g / eq. The melt viscosity at 150 ° C. was 3.08 Pa · s.

GPC charts of the phenol resins obtained in Synthesis Examples 1, 3, 5, and 7 are shown in FIGS. 1, 3, 5, and 7, and GPC charts of the epoxy resins obtained in Synthesis Examples 2, 4, 6, and 8 are shown. It is shown in FIGS.

Example 1
As an epoxy resin component, 100 g of epoxy resin A obtained in Synthesis Example 2, and as a curing agent component, phenol novolac (PSM-4324 (manufactured by Gunei Chemical Industry Co., Ltd.), OH equivalent 105, softening point: 100 ° C.) 57.5 g Was used. Further, 0.7 g of curing accelerator A; 2-methylimidazole (manufactured by Tokyo Chemical Industry Co., Ltd.) was used and kneaded to obtain an epoxy resin composition. Using this epoxy resin composition, a cured product test piece was obtained at a molding temperature of 175 ° C. for 3 minutes and a post-cure temperature of 250 ° C. for 5 hours (molding condition A). It was measured. The results are shown in Table 1.

Example 2
A 5% weight loss temperature was measured in the same manner as in Example 1 except that 100 g of the epoxy resin E obtained in Synthesis Example 8 was used as the epoxy resin component. The results are shown in Table 1.

Comparative Example 1
A 5% weight loss temperature was measured in the same manner as in Example 1 except that 100 g of the epoxy resin B obtained in Synthesis Example 4 was used as the epoxy resin component. The results are shown in Table 1.

Comparative Example 2
A 5% weight loss temperature was measured in the same manner as in Example 1 except that 100 g of the epoxy resin D obtained in Synthesis Example 6 was used as the epoxy resin component. The results are shown in Table 1.

Examples 3 to 15 and Comparative Examples 3 and 4
The epoxy resins A and E obtained in the above synthesis examples, or the epoxy resin C, a curing agent, an inorganic filler, a curing accelerator (curing catalyst), and other additives are kneaded at a blending ratio shown in Tables 2 to 3. Thus, an epoxy resin composition was prepared. The numerical value in a table | surface shows the weight part in mixing | blending.

Explanation of abbreviations in the table Epoxy resin C: o-cresol novolac type epoxy resin (epoxy equivalent 200, softening point 65 ° C., manufactured by Nippon Steel Chemical Co., Ltd.)
(Curing agent)
PN: phenol novolak (PSM-4324, OH equivalent 105, softening point: 100 ° C., manufactured by Gunei Chemical Industry Co., Ltd.)
TPM: Triphenolmethane (TPM-100, OH equivalent 97.5, softening point 105 ° C., manufactured by Gunei Chemical Industry Co., Ltd.)
(Inorganic filler)
Spherical silica (Product name: FB-8S, manufactured by Denki Kagaku Kogyo Co., Ltd.)
(Curing accelerator)
A; 2-methylimidazole (manufactured by Tokyo Chemical Industry Co., Ltd.)
B: 2-Phenyl-4,5-dihydroxymethylimidazole (2PHZ-PW, manufactured by Shikoku Kasei Co., Ltd.)
C: Tris- (2,6-dimethoxyphenyl) phosphine (manufactured by Tokyo Chemical Industry Co., Ltd.)
(Silane coupling agent)
4-Aminopropylethoxysilane (KBR-903, manufactured by Shin-Etsu Chemical Co., Ltd.)
(Release agent)
Carnauba wax (TOWAX171, manufactured by Toa Kasei Co., Ltd.)
(Coloring agent)
Carbon black (MA-100, manufactured by Mitsubishi Chemical Corporation)

Using this epoxy resin composition, molding was performed under the following molding conditions. After obtaining a cured product test piece, it was subjected to various physical property measurements. The results are shown in Tables 2-3.
Molding conditions A: Molding temperature 175 ° C., 3 minutes. Post cure temperature 250 ° C., 5 hours B; Molding temperature 175 ° C., 3 minutes. Post cure temperature 175 ° C, 5 hours

1) Measurement of epoxy equivalent Using a potentiometric titrator, methyl ethyl ketone was used as a solvent, a brominated tetraethylammonium acetic acid solution was added, and the potential was measured using a 0.1 mol / L perchloric acid-acetic acid solution.

2) Melt viscosity Measured at 150 ° C. using a CV-1S type cone plate viscometer manufactured by Toa Kogyo Co., Ltd.

3) Glass transition point (Tg)
Tg was determined under the condition of a temperature increase rate of 10 ° C./min using a Seiko Instruments TMA6100 thermomechanical measuring device.

4) Long-term pyrolysis stability evaluation (weight retention)
Using a thermostat with a rotating frame (GPHH-201, manufactured by Tabai Espec Co., Ltd.), obtain the weight retention rate (wt%) from the difference between the specimen weight after 1000 hours at 250 ° C and the specimen weight before heating. It was.

5) Spiral flow An epoxy resin composition was molded using a spiral flow measurement mold in accordance with the standard (EMMI-1-66) under the conditions of spiral flow injection pressure (150 kgf / cm 2) and curing time of 3 minutes. The flow length at 0 ° C. was examined.
6) DSC exothermic peak temperature An exothermic peak temperature was determined under the condition of a temperature rising rate of 10 ° C / min using a DSC6200 thermomechanical measuring device manufactured by Seiko Instruments Inc.

7) 5% weight reduction temperature A 5% weight reduction temperature was determined by a TG / DTA6200 type thermomechanical measurement device manufactured by Seiko Instruments Inc. under a nitrogen atmosphere under a temperature increase rate of 10 ° C./min.
8) Flexural strength and flexural elasticity Measured at room temperature and 250 ° C. by a three-point bending test method according to JISK 6911.
9) Bending strength and elastic modulus retention rate The bending strength and bending elastic modulus at high temperatures (250 ° C) were determined with respect to the bending strength and bending elastic modulus at room temperature. A higher value indicates less change in physical properties with room temperature.

Claims

An epoxy resin represented by the following general formula (2).

Here, R independently represents a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, and G represents a glycidyl group. n is the number of repetitions, and includes 10% or more of multimers in which n is 1 or more.
The following general formula (1)

Here, R independently represents a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, G represents a glycidyl group, and n represents a repeating number.
An epoxy resin obtained by reacting a polyhydroxy compound having a component of n = 1 or more and 10% or more in an area% measured by gel permeation chromatography with epichlorohydrin.
An epoxy resin composition comprising the epoxy resin according to claim 2, a phenolic curing agent, a curing catalyst, and an inorganic filler.
An epoxy resin composition comprising the epoxy resin according to claim 1, a phenol-based curing agent, a curing catalyst, and an inorganic filler.
The epoxy resin composition according to claim 3, wherein the curing catalyst is at least one selected from the group consisting of imidazoles, organic phosphines, and amines.
The epoxy resin composition according to claim 3, wherein the curing catalyst has an exothermic peak top of 150 ° C or higher when the epoxy resin composition is measured by DSC at a temperature rising rate of 10 ° C / min.
A method for curing an epoxy resin composition, comprising molding the epoxy resin composition according to claim 3 at 100 ° C to 200 ° C and then post-curing at 200 ° C to 300 ° C.
4. A cured epoxy resin obtained by molding the epoxy resin composition according to claim 3 at 100 ° C. to 200 ° C. and then post-curing at 200 ° C. to 300 ° C.
The cured epoxy resin product according to claim 8, which is a cured epoxy resin product for a semiconductor encapsulant.
A semiconductor device, wherein a semiconductor element is sealed with the cured epoxy resin according to claim 9.