JP6772680B2 - Epoxy resin, epoxy resin composition, cured product and electrical / electronic parts - Google Patents

Description

The present invention relates to a tetramethylbiphenol type epoxy resin having excellent solvent solubility and a small amount of hydrolyzable chlorine, and an epoxy resin composition and a cured product having excellent heat resistance containing the epoxy resin. Further, the epoxy resin composition of the present invention is useful for electrical and electronic parts.

Epoxy resins generally become cured products with excellent mechanical properties, heat resistance, electrical properties, etc. by curing with various curing agents. Therefore, a wide range of fields such as adhesives, paints, electrical and electronic materials, etc. It is used in. In particular, in the field of electrical and electronic materials, tetramethylbiphenol type epoxy resins are often used as semiconductor encapsulants because they can provide encapsulants with high added value.

Patent Document 1 describes that a tetramethylbiphenol type epoxy resin was produced by the reaction of 4,4'-bishydroxy-3,3', 5,5'-tetramethylbiphenyl and epichlorohydrin.

Patent Document 2 describes a tetramethylbiphenol type epoxy resin having an epoxy equivalent of 190 g / eq or less and a hydrolyzable chlorine amount of 500 ppm or less. Specifically, the epoxy equivalent is 184 g / eq and the hydrolyzable chlorine amount. Is 290 ppm, or an epoxy equivalent of 182 g / eq and a hydrolyzable chlorine content of 230 ppm have been shown to produce a tetramethylbiphenol type epoxy resin.

Patent Document 3 describes a solution of KOH or NaOH / isopropanol in a mixed solvent of isobutyl ketone and dimethyl sulfoxide in a commercially available tetramethylbiphenol type epoxy resin (“Epicoat YX4000”, epoxy equivalent 186, total organic halogen content 1180 ppm). It is described that an epoxy resin having an epoxy equivalent of 188 or 190 and a total organic chlorine content of 410 or 340 ppm was obtained by adding and reacting at 70 ° C. or 60 ° C.

In Patent Document 4, for the purpose of improving moisture resistance reliability, the weight average molecular weight (Mw) is 300 to 800, and the ratio (Mw / Mn) of Mw to the number average molecular weight (Mn) is 1.0 to 1. The tetramethylbiphenol type epoxy resin of No. 5 is disclosed.

Non-Patent Document 1 discloses biphenyl-type epoxy resins that are standardly used as sealing materials, as well as practical epoxy resins for electronic materials, and their hydrolyzable chlorine content is 500 to 700 ppm. It is shown to be.

Japanese Unexamined Patent Publication No. 58-039677 Japanese Unexamined Patent Publication No. 10-147629 Japanese Unexamined Patent Publication No. 2000-239346 Japanese Unexamined Patent Publication No. 5-36867

Epoxy Resin Technology Association, "Review Epoxy Resin Latest Advances I" (First Edition), Epoxy Resin Association, March 18, 2009, p. 8-11

Patent Document 1 does not describe the number average molecular weight (Mn) and the weight average molecular weight (Mw) of the epoxy resin. As shown in Comparative Example 4 described later, the epoxy resin described in Patent Document 1 has both a number average molecular weight (Mn) and a weight average molecular weight (Mw) outside the present invention, and is inferior in solvent solubility.

Patent Document 2 does not describe the number average molecular weight (Mn) and the weight average molecular weight (Mw) of the epoxy resin. Although the epoxy equivalent described in Patent Document 2 has a low epoxy equivalent, it can be said that the epoxy resin has a smaller molecule than the epoxy resin of the present invention because it has few chlorine impurities and the epoxy is closed.

The tetramethylbiphenol type epoxy resin has excellent heat resistance and moisture absorption resistance due to its rigid tetramethylbiphenyl skeleton, and has a low melt viscosity at 150 ° C., so that the filler can be highly filled as a semiconductor encapsulant. Although it is possible and effective in preventing wire flow during molding of a sealing material on a semiconductor, it has the following drawbacks.
That is, in electric / electronic material applications, an epoxy resin may be dissolved in a solvent and used as a varnish, but the tetramethylbiphenol type epoxy resin is inferior in solvent solubility due to its rigid tetramethylbiphenyl skeleton. In addition, the amount of hydrolyzable chlorine is not at a sufficient level in terms of low chlorination required in recent years.

In Patent Document 3, the solvent solubility of the tetramethylbiphenol type epoxy resin has not been examined. Moreover, the total organic chlorine content is not sufficiently reduced. This Patent Document 3 also does not describe the number average molecular weight (Mn) and the weight average molecular weight (Mw) of the epoxy resin, and the number average molecular weight (Mn) and the weight average molecular weight (Mw) of Epicoat YX4000 are the present invention. It is out of the specified range of.

In Patent Document 4, it is described that the epoxy resin is used as a sealing material for a semiconductor device, and the amount of hydrolyzable chlorine thereof is preferably 600 ppm or less, but in the examples, the ring closure reaction is carried out once. It is estimated that the amount of hydrolyzable chlorine remains at several thousand ppm, which is quite large. Further, as described in Non-Patent Document 1, since the amount of hydrolyzable chlorine of the conventional product is about 500 ppm, Patent Document 4 does not aim for a smaller amount of hydrolyzable chlorine. That is, Patent Document 4 does not disclose any tetramethylbiphenol type epoxy resin having a small amount of hydrolyzable chlorine and a specific molecular weight.

The subject of the present invention is a tetramethylbiphenol type epoxy resin having excellent solvent solubility and a small amount of hydrolyzable chlorine as compared with conventional products, an epoxy resin composition having excellent heat resistance containing this epoxy resin, and a cured product thereof. Is to provide.
Another object of the present invention is to provide an electric / electronic component made of the epoxy resin composition.

As a result of diligent studies by the present inventor to solve the above problems, a tetramethylbiphenol type epoxy resin in which the number average molecular weight (Mn), the weight average molecular weight (Mw) and the hydrolyzable chlorine amount are controlled within a specific range, and this We have found that an epoxy resin composition containing an epoxy resin and a curing agent can solve the above-mentioned problems, and have completed the present invention.
The tetramethylbiphenol type epoxy resin of the present invention does not exist in the past, and it is a finding found by the present inventor that this epoxy resin has excellent solvent solubility and gives a cured product having excellent heat resistance.
That is, the gist of the present invention lies in the following [1] to [8].

（式中、ｎは０〜１０の整数を表す。）
［２］ 加水分解性塩素の含有量が９０ｐｐｍ以下である［１］に記載のエポキシ樹脂。
［３］ １５０℃における溶融粘度が３．０Ｐａ・ｓ以下である［１］又は［２］に記載のエポキシ樹脂。
［４］ ［１］から［３］のいずれかに記載のエポキシ樹脂１００重量部に対し、硬化剤を０．１〜１０００重量部含むエポキシ樹脂組成物。
［５］ 前記硬化剤がフェノール系硬化剤、アミン系硬化剤、酸無水物系硬化剤及びアミド系硬化剤からなる群から選ばれる少なくとも１種である［４］に記載のエポキシ樹脂組成物。
［６］ ［１］から［３］のいずれかに記載のエポキシ樹脂とは異なるエポキシ樹脂を更に含む［４］または［５］に記載のエポキシ樹脂組成物。
［７］ ［４］から［６］のいずれかに記載のエポキシ樹脂組成物を硬化させてなる硬化物。
［８］ ［４］から［６］のいずれかに記載のエポキシ樹脂組成物を硬化させてなる電気・電子部品。 [1] Epoxy represented by the following formula (1), having a number average molecular weight (Mn) of 270 to 460, a weight average molecular weight (Mw) of 370 to 6080, and a hydrolyzable chlorine content of 300 ppm or less. resin.

(In the formula, n represents an integer from 0 to 10.)
[2] The epoxy resin according to [1], wherein the content of hydrolyzable chlorine is 90 ppm or less.
[3] The epoxy resin according to [1] or [2], which has a melt viscosity at 150 ° C. of 3.0 Pa · s or less.
[4] An epoxy resin composition containing 0.1 to 1000 parts by weight of a curing agent with respect to 100 parts by weight of the epoxy resin according to any one of [1] to [3].
[5] The epoxy resin composition according to [4], 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.
[6] The epoxy resin composition according to [4] or [5], which further contains an epoxy resin different from the epoxy resin according to any one of [1] to [3].
[7] A cured product obtained by curing the epoxy resin composition according to any one of [4] to [6].
[8] An electrical / electronic component obtained by curing the epoxy resin composition according to any one of [4] to [6].

According to the present invention, an epoxy resin composition having excellent heat resistance, which comprises a tetramethylbiphenol type epoxy resin having excellent solvent solubility and a small amount of hydrolyzable chlorine as compared with conventional products and the tetramethylbiphenol type epoxy resin. A product and a cured product are provided.
Since the epoxy resin composition of the present invention has the above-mentioned effects, it can be particularly effectively applied to electric / electronic parts such as semiconductor encapsulants and laminated plates.

The embodiments of the present invention will be described in detail below, but the following description is an example of the embodiments of the present invention, and the present invention is not limited to the following description as long as the gist thereof is not exceeded. Absent. In addition, when the expression "-" is used in this specification, it shall be used as an expression including numerical values or physical property values before and after the expression.

〔Epoxy resin〕
The epoxy resin of the present invention is a tetramethylbiphenol type epoxy resin represented by the following formula (1), which has excellent solvent solubility, a small amount of hydrolyzable chlorine, and an appropriate melt viscosity. ..

(In the formula, n represents an integer from 0 to 10.)

In the present invention, the solvent to be evaluated for solvent solubility is not particularly limited, but for example, in addition to the polar solvents shown below, aromatic hydrocarbon solvents such as benzene and toluene, and aliphatic hydrocarbons such as hexane are used. Examples include solvents.
The polar solvent is not particularly limited, and examples thereof include ketones such as methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), and acetone, and alcohols such as methanol and ethanol.

Since the epoxy resin of the present invention has excellent solvent solubility, more epoxy resin can be dissolved in the solvent when the epoxy resin is dissolved in the solvent, and the degree of freedom in compounding formulation is high.
In addition, since the epoxy resin of the present invention has a small amount of hydrolyzable chlorine, free chlorine when it is made into a cured product is reduced, so that wiring corrosion of electrical and electronic devices is prevented, and troubles such as poor insulation are caused. Can be prevented.
In addition, since the epoxy resin of the present invention has an appropriate melt viscosity, it is also excellent in handleability.

The number of epoxy groups in the tetramethylbiphenol type epoxy resin represented by the formula (1) (hereinafter, may be referred to as "epoxy resin (1)") is shown as an epoxy equivalent described later.
Further, n in the formula (1) showing the epoxy resin (1) is an integer of 0 to 10, and the epoxy resin (1) is used as a mixture of a plurality of compounds having different n in the range of n = 0 to 10. Provided.

[Weight average molecular weight (Mw)]
The epoxy resin (1) preferably has an Mw of 370 to 6080 from the viewpoint of obtaining excellent solvent solubility, and preferably 370 to 2675 from the viewpoint of making the melt viscosity a good value, further improving the solvent solubility. From the viewpoint of making it excellent, it is more preferably 445 to 2675. Further, from the viewpoint of lowering the content of hydrolyzable chlorine and excellent electrical characteristics, Mw is particularly preferably 615 to 2675.

The mechanism by which the solvent solubility is improved is not clear, but when Mw is within the above range, the crystallinity is inhibited by the oligomer component represented by the formula (1) contained in the epoxy resin (1). It is thought that this is the case.

The weight average molecular weight (Mw) of the epoxy resin can be measured as a polystyrene-equivalent value by gel permeation chromatography.

[Number average molecular weight (Mn)]
The epoxy resin (1) preferably has Mn of 270 to 460 from the viewpoint of obtaining excellent solvent solubility, and preferably 270 to 411 from the viewpoint of making the melt viscosity a good value, further improving the solvent solubility. From the viewpoint of making it excellent, it is more preferably 281 to 411. Further, from the viewpoint that the content of hydrolyzable chlorine is low and the electrical characteristics are excellent, Mn is particularly preferably 304 to 411.

The mechanism by which the solvent solubility is improved is not clear, but when Mn is within the above range, the crystallinity is inhibited by the oligomer component represented by the formula (1) contained in the epoxy resin (1). It is thought that this is the case.

The number average molecular weight (Mn) of the epoxy resin can be measured as a polystyrene-equivalent value by gel permeation chromatography.

It is known that Mw and Mn are calculated from the following equation.
Mw = Σ (Mi ²・ Ni) / Σ (Mi ・ Ni)
Mn = Σ (Mi ・ Ni) / Σ (Ni)
M represents the molecular weight, N represents the number of molecules, Mw is a weighted average using the molecular weight as a weight, and Mn is a simple arithmetic mean. In general, low-molecular-weight epoxy resins have a monomer component as the main component during synthesis, and it is difficult for a large difference in the values of Mw and Mn to appear, but an epoxy resin having a large amount of oligomer components has a large difference in Mw and Mn.

[Preferable combination of Mn and Mw]
The epoxy resin (1) has Mw of 370 to 6080 and Mn of 270 to 460 from the viewpoint of obtaining excellent solvent solubility, and Mw of 370 to 2675 and Mn of 270 from the viewpoint of improving the melt viscosity. It is preferably ~ 411, and more preferably Mw is 445-2675 and Mn is 281 to 411 from the viewpoint of further improving the solvent solubility. Further, from the viewpoint that the content of hydrolyzable chlorine is low and the electrical characteristics are excellent, it is particularly preferable that Mw is 615 to 2675 and Mn is 304 to 411.

The mechanism by which the solvent solubility is improved is not clear, but when Mn and Mw are within the above ranges, the crystallinity is inhibited by the oligomer component represented by the formula (1) contained in the epoxy resin (1). It is thought that it depends on being done.

[Epoxy equivalent]
The epoxy resin (1) preferably has an epoxy equivalent of 195 to 275 g / equivalent from the viewpoint of obtaining excellent solvent solubility, and preferably has an epoxy equivalent of 195 to 255 g / equivalent from the viewpoint of making the melt viscosity a good value. More preferably, it is more preferably 200 to 255 g / equivalent from the viewpoint of further improving the solvent solubility. Further, the epoxy equivalent is particularly preferably 209 to 255 g / equivalent from the viewpoint of lowering the content of hydrolyzable chlorine and excellent electrical characteristics.

The mechanism by which the solvent solubility is improved is not clear, but when the epoxy equivalent is within the above range, the crystallinity is inhibited by the oligomer component represented by the formula (1) contained in the epoxy resin (1). It is thought that it depends.

In the present invention, "epoxy equivalent" is defined as "mass of epoxy resin containing 1 equivalent of epoxy group" and can be measured according to JIS K7236.

[Preferable combination of Mn and epoxy equivalents]
The epoxy resin (1) preferably has an epoxy equivalent of 195 to 275 g / equivalent and a Mn of 270 to 460 from the viewpoint of obtaining excellent solvent solubility, and an epoxy equivalent from the viewpoint of improving the melt viscosity. Is 195 to 255 g / equivalent and Mn is 270 to 411. From the viewpoint of further improving solvent solubility, the epoxy equivalent is 200 to 255 g / equivalent and Mn is 281 to 411. Is even more preferable. Further, from the viewpoint of lowering the content of hydrolyzable chlorine and excellent electrical characteristics, it is particularly preferable that the epoxy equivalent is 209 to 255 g / equivalent and the Mn is 304 to 411.

The mechanism by which the solvent solubility is improved is not clear, but when the Mn and epoxy equivalents are within the above ranges, the crystallinity is increased by the oligomer component represented by the formula (1) contained in the epoxy resin (1). It is thought that it is due to being inhibited.

[Preferable combination of Mw and epoxy equivalent]
The epoxy resin (1) preferably has an epoxy equivalent of 195 to 275 g / equivalent and a Mw of 370 to 6080 from the viewpoint of obtaining excellent solvent solubility, and an epoxy equivalent from the viewpoint of improving the melt viscosity. Is 195 to 255 g / equivalent and Mw is 370 to 2675, and from the viewpoint of further improving solvent solubility, the epoxy equivalent is 200 to 255 g / equivalent and Mw is 445 to 2675. Is even more preferable. Further, from the viewpoint of lowering the content of hydrolyzable chlorine and excellent electrical characteristics, it is particularly preferable that the epoxy equivalent is 209 to 255 g / equivalent and the Mw is 615 to 2675.

The mechanism by which the solvent solubility is improved is not clear, but when Mw and the epoxy equivalent are within the above ranges, the crystallinity is increased by the oligomer component represented by the above formula (1) contained in the epoxy resin (1). It is thought that it is due to being inhibited.

[Preferable combination of Mn, Mw and epoxy equivalents]
From the viewpoint of obtaining excellent solvent solubility, the epoxy resin (1) preferably has an epoxy equivalent of 195 to 275 g / equivalent, Mw of 370 to 6080, and Mn of 270 to 460, and has a good melt viscosity. It is more preferable that the epoxy equivalent is 195 to 255 g / equivalent, Mw is 370 to 2675, and Mn is 270 to 411, and the epoxy equivalent is 200 to 200 to further improve the solvent solubility. It is more preferable that Mw is 445 to 2675 and Mn is 281 to 411 at 255 g / equivalent. Further, from the viewpoint of lowering the content of hydrolyzable chlorine and excellent electrical characteristics, it is particularly preferable that the epoxy equivalent is 209 to 255 g / equivalent, Mw is 615 to 2675, and Mn is 304 to 411.

The mechanism by which the solvent solubility is improved is not clear, but when Mn, Mw, and the epoxy equivalent are within the above ranges, crystals are formed by the oligomer component represented by the above formula (1) contained in the epoxy resin (1). It is thought that this is due to the inhibition of sex.

In order to set the epoxy equivalent of the epoxy resin (1) and Mw and Mn in the above-mentioned preferable ranges, in the method for producing the epoxy resin (1) described later, the crude epoxy resin is purified by the reaction between the crude epoxy resin and the strong alkali. , The amount of strong alkali used, the reaction temperature, and the reaction time may be controlled.
Further, by a method of sampling over time and analyzing with GPC, each numerical value can be confirmed and a desired resin can be obtained.

[Amount of hydrolyzable chlorine]
The epoxy resin (1) has a hydrolyzable chlorine content (hereinafter, may be referred to as “hydrolyzable chlorine amount”) of 300 ppm or less. When the amount of hydrolyzable chlorine is 300 ppm or less, the solvent solubility becomes good. In particular, the solubility in a polar solvent becomes good.
In addition, "ppm" in this hydrolyzable chlorine amount means weight ppm.

The smaller the amount of hydrolyzable chlorine is, the more preferable it is in terms of electrical reliability of the obtained product, preferably 200 ppm or less, more preferably 90 ppm or less, and particularly preferably 80 ppm or less. The lower limit of the amount of hydrolyzable chlorine is 0 ppm, that is, "below the detection limit" in the measurement of the amount of hydrolyzable chlorine below, but if the amount of hydrolyzable chlorine is excessively low, the epoxy equivalent and Mw and Mn are increased. The lower limit of the amount of hydrolyzable chlorine is usually 10 ppm because it is difficult to set it in a suitable range.

As a method for measuring the amount of hydrolyzable chlorine, for example, about 0.5 g of epoxy resin is 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. There is a method of quantifying this.

In order to reduce the amount of hydrolyzable chlorine in the epoxy resin (1), the crude epoxy resin may be purified by reacting the crude epoxy resin with a strong alkali in the method for producing the epoxy resin (1) described later.

[Melting viscosity]
From the viewpoint of handleability, the epoxy resin (1) preferably has a melt viscosity at 150 ° C. of 3.0 Pa · s or less, and from the viewpoint of improving handleability, the melt viscosity is 0. It is more preferably 001 Pa · s or more and 1.4 Pa · s or less.

In the present invention, the "melt viscosity" is a viscosity measured at a rotation speed of 750 rpm by melting an epoxy resin on a hot plate of a cone plate viscometer (manufactured by Tokai Yagami Co., Ltd.) adjusted to 150 ° C. ..

In order to keep the melt viscosity of the epoxy resin (1) within the above-mentioned preferable range, epichlorohydrin is used for the raw material polyvalent hydroxy compound in the method for producing the epoxy resin (1) described later, for example, in the case of the one-step method. The amount may be controlled, and the melt viscosity can be lowered by increasing the amount of epichlorohydrin, and the melt viscosity can be increased by decreasing the amount.

[Manufacturing method of epoxy resin (1)]
The epoxy resin (1) of the present invention in which the amounts of Mw, Mn, and hydrolyzable chlorine are in the above-mentioned ranges and further satisfy the above-mentioned preferable epoxy equivalent and melt viscosity is a tetramethylbiphenol type epoxy resin (1) according to a conventional method. Hereinafter, it may be referred to as "crude epoxy resin"), and then it can be produced by reacting it with a strong alkali to purify it.

[Manufacturing method of crude epoxy resin]
The method for producing the crude epoxy resin is not particularly limited, and examples thereof include a one-step method described below.

<Manufacturing method by one-step method>
In the production method by the one-step method, 4,4'-bishydroxy-3,3', 5,5'-tetramethylbiphenyl represented by the following formula may be referred to as "tetramethylbiphenol (2)". ) And epichlorohydrin to produce a crude epoxy resin.

When the crude epoxy resin is produced by the one-step method, at least tetramethylbiphenol (2) and epichlorohydrin are used as raw materials, but polyvalent hydroxy compounds other than tetramethylbiphenol (2) (hereinafter, “other polyvalent hydroxy compounds”). ”) May be used in combination to produce a mixture of the epoxy resin (1) and another epoxy resin.

However, from the viewpoint of enhancing the effect of the present invention, the ratio of tetramethylbiphenol (2) is preferably 30 mol% or more, more preferably 50 mol% or more, still more preferably 50 mol% or more, based on the total amount of the polyvalent hydroxy compound used as a raw material. Is 80 mol% or more, particularly preferably 100 mol%. The upper limit is 100 mol%.
The "multivalent hydroxy compound" in the present invention is a general term for a divalent or higher phenol compound and a divalent or higher alcohol.

Other polyhydric hydroxy compounds include bisphenol A, bisphenol F, bisphenol S, bisphenol AD, bisphenol AF, hydroquinone, resorcin, methylresorcin, biphenol, dihydroxynaphthalene, dihydroxydiphenyl ether, thiodiphenols, phenol novolac resin, cresol novolac. Various polyhydric phenols such as resin, phenol aralkyl resin, biphenyl aralkyl resin, naphthol aralkyl resin, terpenphenol resin, dicyclopentadienephenol resin, bisphenol A novolac resin, naphthol novolac resin, brominated bisphenol A, brominated phenol novolac resin Xylene, a polyhydric phenolic resin obtained by a condensation reaction between various phenols (excluding tetramethylbiphenol (2)) and various aldehydes such as benzaldehyde, hydroxybenzaldehyde, crotonaldehyde, and glioxal. Various phenolic resins such as polyhydric phenolic resins obtained by the condensation reaction of resins and phenols, heavy oils or pitches and cocondensate resins of phenols and formaldehyde, ethylene glycol, trimethylene glycol, propylene Chain aliphatic diols such as glycol, 1,3-butanediol, 1,4-butanediol, 1,3-pentanediol, 1,4-pentanediol, 1,5-pentanediol, 1,6-hexanediol Examples include cyclic aliphatic diols such as cyclohexanediol and cyclodecanediol, and polyalkylene ether glycols such as polyethylene ether glycol, polyoxytrimethylene ether glycol and polypropylene ether glycol.

Of these, preferred are phenol novolac resin, phenol aralkyl resin, polyhydric phenol resin obtained by condensation reaction of phenol and hydroxybenzaldehyde, biphenyl aralkyl resin, naphthol aralkyl resin, ethylene glycol, trimethylene glycol, propylene glycol. , 1,3-Butandiol, 1,4-Butandiol, 1,3-Pentanediol, 1,4-Pentanediol, 1,5-Pentanediol, 1,6-Hexanediol and other chain aliphatic diols. , Cycloaliphatic diols such as cyclohexanediol and cyclodecanediol, and polyalkylene ether glycols such as polyethylene ether glycol, polyoxytrimethylene ether glycol and polypropylene ether glycol.

The tetramethylbiphenol (2) used as a raw material and other polyvalent hydroxy compounds used as needed are usually 0.8 to 20 equivalents, preferably 0.8 to 20 equivalents, per 1 equivalent of the hydroxyl group of the total polyvalent hydroxy compound, which is the total of these. Is dissolved in 0.9 to 15 equivalents, more preferably 1.0 to 10 equivalents of epichlorohydrin to give a uniform solution. When the amount of epichlorohydrin is at least the above lower limit, it is easy to control the high molecular weight reaction, and the obtained epoxy resin can have an appropriate melt viscosity, which is preferable. On the other hand, when the amount of epichlorohydrin is not more than the above upper limit, the production efficiency tends to be improved, which is preferable.

Then, while stirring the solution, it is usually 0.5 to 2.0 equivalents, preferably 0.7 to 1.8 equivalents, more preferably 0.9 equivalents per hydroxyl group of the raw material total polyvalent hydroxy compound. Add an amount of alkali metal hydroxide corresponding to ~ 1.6 equivalents in solid or aqueous solution and react. When the amount of the alkali metal hydroxide is not less than the above lower limit, it is preferable because the unreacted hydroxyl group and the generated epoxy resin do not easily react with each other and the high molecular weight reaction can be easily controlled. Further, when the amount of the alkali metal hydroxide is not more than the above upper limit value, impurities due to side reactions are less likely to be generated, which is preferable. The alkali metal hydroxide used here usually includes sodium hydroxide or potassium hydroxide.

This reaction can be carried out under normal pressure or reduced pressure, and the reaction temperature is preferably 40 to 150 ° C., more preferably 60 to 100 ° C., still more preferably 80 to 100 ° C. When the reaction temperature is at least the above lower limit, it is preferable because the reaction can be easily proceeded and the reaction can be easily controlled. Further, when the reaction temperature is not more than the above upper limit, side reactions are less likely to proceed, and chlorine impurities are particularly easy to reduce, which is preferable.

In the reaction, if necessary, the reaction solution is azeotroped while maintaining a predetermined temperature, the volatilized vapor is cooled, the obtained condensate is separated into oil / water, and the oil content excluding water is returned to the reaction system. It is carried out while dehydrating by the method. The alkali metal hydroxide is intermittently added in small amounts over 0.1 to 8 hours, more preferably 0.1 to 7 hours, and even more preferably 0.5 to 6 hours in order to suppress a rapid reaction. Or add continuously. When the addition time of the alkali metal hydroxide is not less than the above lower limit, it is possible to prevent the reaction from progressing rapidly, and it is preferable because the reaction temperature can be easily controlled. When the addition time is not more than the above upper limit, chlorine impurities are less likely to be generated, which is preferable, and also from the viewpoint of economic efficiency. The total reaction time is usually 1 to 15 hours. After completion of the reaction, the insoluble by-product salt is removed by filtration or removed by washing with water, and then the unreacted epichlorohydrin is removed by distillation under reduced pressure to obtain the desired crude epoxy resin.

In this reaction, quaternary ammonium salts such as tetramethylammonium chloride and tetraethylammonium bromide, benzyldimethylamine, tertiary amines such as 2,4,6-tris (dimethylaminomethyl) phenol, and 2-ethyl Catalysts such as imidazoles such as -4-methylimidazole and 2-phenylimidazole, phosphonium salts such as ethyltriphenylphosphonium iodide, and phosphines such as triphenylphosphine may be used.

Furthermore, in this reaction, alcohols such as ethanol and isopropanol, ketones such as acetone and methyl ethyl ketone, ethers such as dioxane and ethylene glycol dimethyl ether, glycol ethers such as methoxypropanol, and aprotic such as dimethyl sulfoxide and dimethylformamide. An inert organic solvent such as a protic solvent may be used.

[Purification of crude epoxy resin]
In the present invention, the crude epoxy resin produced as described above is purified by reacting with a strong alkali to improve solvent solubility and reduce the amount of hydrolyzable chlorine.
Further, by the reaction with this strong alkali, Mw and Mn, and further the epoxy equivalent can be adjusted to the preferable range specified in the present invention.

That is, for example, Mw can be increased by increasing the temperature, the resin content with respect to the solvent, and the amount of alkali, and conversely, Mw can be decreased by decreasing the temperature, the resin content with respect to the solvent, and the amount of alkali. can do. Further, Mn can be increased by increasing the temperature, the resin content with respect to the solvent, and the amount of alkali, and conversely, the Mn can be decreased by decreasing the temperature, the resin content with respect to the solvent, and the amount of alkali. Can be done. Further, the epoxy equivalent can be increased by increasing the temperature, the resin content with respect to the solvent, and the alkali amount, and conversely, the epoxy equivalent can be decreased by decreasing the temperature, the resin content with respect to the solvent, and the alkali amount. can do.

Regarding the melt viscosity, the melt viscosity can be increased by increasing the temperature, the resin content with respect to the solvent, and the amount of alkali. On the contrary, the melt viscosity can be lowered by lowering the temperature, the resin content with respect to the solvent, and the amount of alkali.

Regarding the content of hydrolyzable chlorine, the content of hydrolyzable chlorine can be lowered by increasing the temperature, the resin content with respect to the solvent, and the alkali content. On the contrary, the content of hydrolyzable chlorine can be increased by lowering the temperature, the resin content with respect to the solvent, and the alkali content.

The detailed conditions for producing the epoxy resin of the present invention will be described below, but since the reaction time may be longer or shorter depending on the conditions, appropriate sampling is performed, and as described above, the amounts of Mw, Mn and hydrolyzable chlorine are determined. Furthermore, a desired epoxy resin can be obtained by analyzing the epoxy equivalent.

An organic solvent for dissolving the epoxy resin may be used for the reaction between the crude epoxy resin and the strong alkali. The organic solvent used in the reaction is not particularly limited, but from the viewpoint of purification efficiency, handleability, workability, etc., an aprotic polar solvent and an inert organic solvent other than the aprotic polar solvent are used. It is preferably a mixed solvent.

Examples of the aprotic polar solvent include dimethyl sulfoxide, diethyl sulfoxide, dimethyl sulfolane, sulfolane, dimethylformamide, dimethylacetamide, hexamethylphosphoramide and the like. One of these may be used alone, or two or more thereof may be mixed and used. Among these aprotic polar solvents, dimethyl sulfoxide is preferable because it is easily available and has excellent effects.

Examples of the organic solvent used together with the aprotonic polar solvent include aromatic hydrocarbon solvents such as benzene, toluene and xylene, ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, and ethers such as dioxane and ethylene glycol dimethyl ether. However, from the viewpoint of effect and ease of post-treatment, an aromatic hydrocarbon solvent or a ketone solvent is preferable, and toluene, xylene or methyl isobutyl ketone is particularly preferable. One of these may be used alone, or two or more thereof may be mixed and used.

The above aprotic polar solvent and other organic solvents are preferably used so that the ratio of the aprotic polar solvent to the total of these is 3 to 20% by weight.

The amount of the organic solvent used is such that the concentration of the crude epoxy resin is usually 3 to 70% by weight, preferably 5 to 50% by weight, and more preferably 10 to 40% by weight. is there.

As the strong alkali, a solid or solution of alkali metal hydroxide can be used, and examples of the alkali metal hydroxide include potassium hydroxide and sodium hydroxide.

The crude epoxy resin obtained by epoxidation of tetramethylbiphenol (2) contains 1,2-chlorohydrin and 1,3-chlorohydrin, which are reacted with a strong alkali to form 1,2-chlorohydrin. Dechlorination progresses to close the ring and epoxidize. By carrying out the reaction of the crude epoxy resin with the strong alkali once or more, preferably twice or more, more preferably three times or more, the 1,2-chlorohydrin compound is reduced and the amount of hydrolyzable chlorine is increased. Decrease.

When potassium hydroxide is used as the alkali metal hydroxide, chlorine atoms such as 1,2-chlorohydrin, 1,3-chlorohydrin, and compounds in which these have reacted with epichlorohydrin can be converted into hydroxyl groups. , The amount of hydrolyzable chlorine can be further reduced, and the solubility in a polar solvent can be improved by introducing a hydroxyl group.

The alkali metal hydroxide may be used by dissolving it in an organic solvent or water.

The amount of the alkali metal hydroxide used is preferably 0.2 parts by weight or more and 1.1 parts by weight or less with respect to 100 parts by weight of the crude epoxy resin in terms of solid content of the alkali metal hydroxide. By setting the amount of the alkali metal hydroxide used in this range, the amount of Mn, Mw and hydrolyzable chlorine of the obtained epoxy resin (1), and further the epoxy equivalent can be easily adjusted within the above-mentioned preferable range. Is possible.

The reaction temperature is preferably 30 to 120 ° C., more preferably 40 to 110 ° C., and the reaction time is preferably 0.1 to 15 hours, more preferably 0.3 to 12 hours.

After the reaction, excess alkali metal hydroxides and by-products are removed by a method such as washing with water, and the organic solvent is further removed by distillation under reduced pressure and / or steam distillation to obtain the epoxy resin (1) of the present invention. be able to.

Examples of the method for controlling the molecular weight of the epoxy resin of the present invention include a method of controlling the molecular weight based on the results of sampling over time and analysis by GPC.
The epoxy resin of the present invention can be produced by epoxidizing with epichlorohydrin and performing the above treatment.

[Epoxy resin composition]
The epoxy resin composition of the present invention contains at least the epoxy resin (1) of the present invention described above and a curing agent. Further, the epoxy resin composition of the present invention includes, if necessary, an epoxy resin other than the epoxy resin (1) of the present invention (hereinafter, may be simply referred to as "another epoxy resin") and cured. Accelerators, inorganic fillers, coupling agents and the like can be appropriately blended.

The epoxy resin composition of the present invention containing the epoxy resin (1) of the present invention having excellent solvent solubility and a small amount of hydrolyzable chlorine has excellent cured product properties such as heat resistance and hygroscopicity, and is required for various applications. It provides a cured product that sufficiently satisfies various physical properties.

That is, since the epoxy resin (1) has a rigid tetramethylbiphenyl skeleton, it provides a cured product having excellent heat resistance and moisture absorption resistance. Epoxy resin compositions and cured products with excellent heat resistance are less likely to be subjected to thermal stress in the sealed resin when used as a semiconductor encapsulant, resulting in passivation, chip damage, aluminum wiring slides, and packaging. It is possible to realize a product having excellent reliability without causing defects such as cracks.

[Hardener]
In the present invention, the curing agent refers to a substance that contributes to the cross-linking reaction and / or the chain length extension reaction between the epoxy groups of the epoxy resin. In the present invention, even if it is usually called a "curing accelerator", if it is a substance that contributes to the cross-linking reaction and / or the chain length extension reaction between the epoxy groups of the epoxy resin, it is regarded as a curing agent. To do.

In the epoxy resin composition of the present invention, the content of the curing agent is preferably 0.1 to 1000 parts by weight with respect to 100 parts by weight of the total epoxy resin component as a solid content. Further, it is more preferably 500 parts by weight or less, and further preferably 300 parts by weight or less. In the present invention, the "solid content" means a component excluding the solvent, and includes not only a solid epoxy resin but also a semi-solid or a viscous liquid substance. Further, the "total epoxy resin component" corresponds to the amount of the epoxy resin contained in the epoxy resin composition of the present invention, and when the epoxy resin composition of the present invention contains only the epoxy resin (1), the epoxy resin. When the amount of (1) is applicable and contains the epoxy resin (1) and another epoxy resin, it corresponds to the total of the epoxy resin (1) and the other epoxy resin.

The curing agent is not particularly limited, and any one generally known as an epoxy resin curing agent can be used. For example, phenol-based curing agents, aliphatic amines, polyether amines, alicyclic amines, amine-based curing agents such as aromatic amines, acid anhydride-based curing agents, amide-based curing agents, tertiary amines, imidazoles, etc. Can be mentioned.
Of these, the epoxy resin composition of the present invention can obtain excellent heat resistance, stress resistance, hygroscopicity, flame retardancy, etc. by containing a phenolic curing agent, and therefore phenol is used as the curing agent. It is preferable to include a system curing agent. Further, from the viewpoint of heat resistance and the like, it is preferable to contain an acid anhydride-based curing agent and an amide-based curing agent. It is also preferable to use imidazoles from the viewpoint of sufficiently advancing the curing reaction and improving heat resistance.

One type of curing agent may be used alone, or two or more types may be used in combination. When two or more kinds of curing agents are used in combination, they may be mixed in advance to prepare a mixed curing agent before use, or when each component of the epoxy resin composition is mixed, each component of the curing agent is used. They may be added separately and mixed at the same time.

<Phenol-based curing agent>
Specific examples of the phenolic curing agent include bisphenol A, bisphenol F, bisphenol S, bisphenol AD, hydroquinone, resorcin, methylresorcin, biphenol, tetramethylbiphenol, dihydroxynaphthalene, dihydroxydiphenyl ether, thiodiphenols, phenol novolac resin, Cresol novolak resin, phenol aralkyl resin, biphenyl aralkyl resin, naphthol aralkyl resin, terpenphenol resin, dicyclopentadienephenol resin, bisphenol A novolak resin, trisphenol methane type resin, naphthol novolak resin, brominated bisphenol A, brominated phenol novolac Polyvalent phenol resins such as resins, polyphenol resins obtained by condensation reaction of various phenols with various aldehydes such as benzaldehyde, hydroxybenzaldehyde, crotonaldehyde, and glioxal, xylene resins and phenols. Polyhydric phenol resins, heavy oils or pitches, co-condensation resins of phenols and formaldehydes, phenol-benzaldehyde / xylylene dimethoxide polycondensate, phenol / benzaldehyde / xylylene dihalide weight obtained by the condensation reaction of Examples thereof include various phenol resins such as condensates, phenol / benzaldehyde / 4,4'-dimethoxyside biphenyl polycondensate, and phenol / benzaldehyde / 4,4'-dihalidebiphenyl polycondensate.
These phenolic curing agents may be used alone or in combination of two or more in any combination and blending ratio.

Among the above phenolic curing agents, from the viewpoint of heat resistance and curability after curing of the composition, phenol novolac resin (for example, a compound represented by the following formula (3)) and phenol aralkyl resin (for example, the following formula (4)). (Compound represented by the following formula), biphenyl aralkyl resin (for example, a compound represented by the following formula (5)), naphthol novolak resin (for example, a compound represented by the following formula (6)), naphthol aralkyl resin (for example, the following formula (7)). ), Trisphenol methane type resin (for example, compound represented by the following formula (8)), phenol / benzaldehyde / xylylene dimethoxide polycondensate (for example, compound represented by the following formula (9)). ), Phenol / benzaldehyde / xylylene dihalide polycondensate (for example, a compound represented by the following formula (9)), phenol / benzaldehyde / 4,4'-dimethoxidebiphenyl polycondensate (for example, in the following formula (10)). (Represented compound), phenol, benzaldehyde, 4,4'-dihalidebiphenyl polycondensate (for example, a compound represented by the following formula (10)) and the like are preferable, and in particular, a phenol novolac resin (for example, the following formula (3)) is preferable. (Compound represented by), phenol aralkyl resin (for example, compound represented by the following formula (4)), biphenyl aralkyl resin (for example, compound represented by the following formula (5)), phenol, benzaldehyde, xylylene dimethoxide weight Condensate (for example, a compound represented by the following formula (9)), phenol / benzaldehyde / xylylene dihalide polycondensate (for example, a compound represented by the following formula (9)), phenol / benzaldehyde / 4,4'-di Phenolicide biphenyl polycondensates (for example, compounds represented by the following formula (10)) and phenol / benzaldehyde / 4,4'-dihalide biphenyl polycondensates (for example, compounds represented by the following formula (10)) are preferable. ..

(However, in the above equations (3) to (8), k _{1 to} k ₆ each indicate a number of 0 or more.)

(However, in the above equations (9) and (10), k ₇ , k ₈ , l ₁ , and l ₂ each indicate a number of 1 or more.)

The blending amount of the phenolic curing agent is preferably 0.1 to 1000 parts by weight, more preferably 500 parts by weight or less, still more preferably 300 parts by weight, based on 100 parts by weight of the total epoxy resin component in the epoxy resin composition. Parts or less, particularly preferably 100 parts by weight or less.

<Amine-based curing agent>
Examples of amine-based curing agents (excluding tertiary amines) include aliphatic amines, polyether amines, alicyclic amines, aromatic amines and the like.

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

Examples of polyether amines include triethylene glycol diamine, tetraethylene glycol diamine, diethylene glycol bis (propylamine), polyoxypropylene diamine, and polyoxypropylene triamines.

Examples of alicyclic amines include isophorone diamine, metacene diamine, N-aminoethylpiperazine, bis (4-amino-3-methyldicyclohexyl) methane, bis (aminomethyl) cyclohexane, and 3,9-bis (3-amino). Examples thereof include propyl) -2,4,8,10-tetraoxaspiro (5,5) undecane and norbornene diamine.

Examples of aromatic amines include tetrachloro-p-xylene diamine, m-xylene diamine, p-xylene diamine, m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, 2,4-diaminoanisol, 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) Examples thereof include ethylamine, diaminodiethyldimethyldiphenylmethane, α, α'-bis (4-aminophenyl) -p-diisopropylbenzene and the like.

The amine-based curing agents mentioned above may be used alone or in combination of two or more in any combination and blending ratio.

The above amine-based curing agent may be used so that the equivalent ratio of the functional groups in the curing agent to the epoxy groups in all the epoxy resin components contained in the epoxy resin composition is in the range of 0.8 to 1.5. preferable. Within this range, unreacted epoxy groups and functional groups of the curing agent are less likely to remain, which is preferable.

Examples of the tertiary amine include 1,8-diazabicyclo (5,4,0) undecene-7, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris (dimethylaminomethyl) phenol and the like. ..

The tertiary amines mentioned above may be used alone or in combination of two or more in any combination and blending ratio.

The above tertiary amine may be used so that the equivalent ratio of the functional group in the curing agent to the epoxy group in the total epoxy resin component contained in the epoxy resin composition is in the range of 0.8 to 1.5. preferable. Within this range, unreacted epoxy groups and functional groups of the curing agent are less likely to remain, which is preferable.

<Acid anhydride-based curing agent>
Examples of the acid anhydride-based curing agent include acid anhydrides and modified products of acid anhydrides.

Examples of the acid anhydride include phthalic acid anhydride, trimellitic acid anhydride, pyromellitic acid anhydride, benzophenone tetracarboxylic acid anhydride, dodecenyl succinic acid anhydride, polyadipic acid anhydride, polyazeline acid anhydride, and polysebacic acid. Anhydrous, poly (ethyloctadecanedioic acid) anhydride, poly (phenylhexadecanedioic acid) anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydrophthalic anhydride , Methyl hymic acid anhydride, trialkyltetrahydrophthalic acid anhydride, methylcyclohexene dicarboxylic acid anhydride, methylcyclohexene tetracarboxylic acid anhydride, ethylene glycol bistrimericate dianhydride, het acid anhydride, nadic acid anhydride, Methylnadic acid anhydride, 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexane-1,2-dicarboxylic acid anhydride, 3,4-dicarboxy-1,2, Examples thereof include 3,4-tetrahydro-1-naphthalene succinic anhydride, 1-methyl-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic anhydride and the like.

Examples of the modified acid anhydride include those obtained by modifying the above-mentioned acid anhydride with glycol. Here, 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. Can be mentioned. Furthermore, copolymerized polyether glycols of two or more kinds of these glycols and / or polyether glycols can also be used.

The modified acid anhydride is preferably modified with 0.4 mol or less of glycol per 1 mol of the acid anhydride. When the amount of modification is not more than the above upper limit, the viscosity of the epoxy resin composition does not become too high, the workability tends to be good, and the speed of the curing reaction with the epoxy resin tends to be good. ..

The acid anhydride-based curing agent mentioned above may be used alone or in combination of two or more in any combination and blending amount.

When an acid anhydride-based curing agent is used, the equivalent ratio of the functional groups in the curing agent to the epoxy groups in all the epoxy resin components in the epoxy resin composition should be in the range of 0.8 to 1.5. Is preferable. Within this range, unreacted epoxy groups and functional groups of the curing agent are less likely to remain, which is preferable.

<Amide-based curing agent>
Examples of the amide-based curing agent include dicyandiamide and its derivatives, polyamide resins and the like.
The amide-based curing agent may be used alone or in combination of two or more in any combination and ratio.
When an amide-based curing agent is used, it is preferable to use the amide-based curing agent in an amount of 0.1 to 20% by weight based on the total of all the epoxy resin components in the epoxy resin composition and the amide-based curing agent.

<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 trimerite, 1-cyanoethyl-2-phenylimidazolium trimerite, 2,4-diamino- 6- [2'-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 Examples thereof include −dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, and an adduct of an epoxy resin and the above-mentioned imidazoles. Since imidazoles have catalytic ability, they can be generally classified as curing accelerators, but in the present invention, they are classified as curing agents.

The above-mentioned imidazoles may be used alone or in admixture of two or more in any combination and ratio.

When imidazoles are used, it is preferable to use imidazoles in an amount of 0.1 to 20% by weight based on the total of all the epoxy resin components in the epoxy resin composition and the imidazoles.

<Other hardeners>
In the epoxy resin composition of the present invention, other curing agents can be used in addition to the curing agent. The other curing agents that can be used in the epoxy resin composition of the present invention are not particularly limited, and all generally known curing agents for epoxy resins can be used.
These other curing agents may be used alone or in combination of two or more.

[Other epoxy resins]
The epoxy resin composition of the present invention may further contain other epoxy resins in addition to the epoxy resin (1). By containing another epoxy resin, the heat resistance, stress resistance, hygroscopicity resistance, flame retardancy and the like of the epoxy resin composition of the present invention can be improved.

All epoxy resins other than the epoxy resin (1) correspond to the other epoxy resins that can be used in the epoxy resin composition of the present invention. Specific examples thereof include bisphenol A type epoxy resin and trisphenol methane type epoxy. Resin, anthracene type epoxy resin, phenol-modified xylene resin type epoxy resin, bisphenol cyclododecyl type epoxy resin, bisphenol diisopropyridene resorcin type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, hydroquinone type epoxy resin, methylhydroquinone Type epoxy resin, dibutyl hydroquinone type epoxy resin, resorcin type epoxy resin, methyl resorcin type epoxy resin, biphenol type epoxy resin, tetramethylbiphenol type epoxy resin other than epoxy resin (1), tetramethylbisphenol F type epoxy resin, dihydroxydiphenyl ether Type epoxy resin, epoxy resin derived from thiodiphenols, dihydroxynaphthalene type epoxy resin, dihydroxyanthracene type epoxy resin, dihydroxydihydroanthracene type epoxy resin, dicyclopentadiene type epoxy resin, epoxy resin derived from dihydroxystilbens , Phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A novolak type epoxy resin, naphthol novolac type epoxy resin, phenol aralkyl type epoxy resin, naphthol aralkyl type epoxy resin, biphenyl aralkyl type epoxy resin, terpenphenol type epoxy resin, Dicyclopentadienephenol type epoxy resin, epoxy resin derived from phenol / hydroxybenzaldehyde condensate, epoxy resin derived from phenol / crotonaldehyde condensate, epoxy resin derived from phenol / glioxal condensate, heavy weight Epoxy resin derived from a cocondensate resin of quality oil or pitches, phenols and formaldehydes, epoxy resin derived from diaminodiphenylmethane, epoxy resin derived from aminophenol, epoxy resin derived from xylenediamine, Examples thereof include an epoxy resin derived from methylhexahydrophthalic acid and an epoxy resin derived from dimer acid.
These may be used alone or in any combination and blending ratio of two or more.

Among these, among the above-mentioned epoxy resins, among the above-mentioned epoxy resins, tetras other than the bisphenol A type epoxy resin and the epoxy resin (1) are considered from the viewpoint of the fluidity of the composition and the heat resistance, moisture absorption resistance, flame retardancy, etc. Methyl biphenol type epoxy resin, 4,4'-biphenol type epoxy resin, biphenyl aralkyl type epoxy resin, phenol aralkyl type epoxy resin, dihydroxyanthracene type epoxy resin, dicyclopentadiene type epoxy resin, orthocresol novolac type epoxy resin, trisphenol A methane-type epoxy resin is particularly preferable.

When the epoxy resin composition of the present invention contains the other epoxy resin described above, the content thereof is preferably 0.01 to 60 parts by weight with respect to 100 parts by weight of all the epoxy resin components in the composition. It is more preferably 40 parts by weight or less, further preferably 30 parts by weight or less, particularly preferably 20 parts by weight or less, and more preferably 1 part by weight or more.

[Curing accelerator]
The epoxy resin composition of the present invention preferably contains a curing accelerator. By including the curing accelerator, the curing time can be shortened and the curing temperature can be lowered, so that a desired cured product can be easily obtained.

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.

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, and tris (tris). Dialkylphenyl) phosphine, tris (trialkylphenyl) phosphine, tris (tetraalkylphenyl) phosphine, tris (dialkoxyphenyl) phosphine, tris (trialkoxyphenyl) phosphine, tris (tetraalkoxyphenyl) phosphine, trialkylphosphine, dialkyl Organic phosphines such as arylphosphine and alkyldiarylphosphine, or complexes of these organic phosphines with organic borons, these organic phosphines and maleic anhydride, 1,4-benzoquinone, 2,5-torquinone, 1,4-naphthoquinone. , 2,3-Didimethylbenzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl-1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, phenyl-1,4-benzoquinone Examples thereof include quinone compounds such as, and compounds obtained by adding a compound such as diazophenylmethane.

Among the curing accelerators listed above, organic phosphines and phosphonium salts are preferable, and organic phosphines are most preferable. Further, as the curing accelerator, only one of the above-mentioned ones may be used, or two or more kinds may be mixed and used in any combination and ratio.

The curing accelerator is preferably used in the range of 0.1% by weight or more and 20 parts by weight or less with respect to 100 parts by weight of all the epoxy resin components in the epoxy resin composition. It is more preferably 0.5 parts by weight or more, further preferably 1 part by weight or more, and more preferably 15 parts by weight or less, still more preferably 10 parts by weight or less. When the content of the curing accelerator is not less than the above lower limit value, a good curing promoting effect can be obtained, while when it is not more than the above upper limit value, desired cured physical properties can be easily obtained, which is preferable.

[Inorganic filler]
An inorganic filler can be blended in the epoxy resin composition of the present invention. Examples of the inorganic filler include fused silica, crystalline silica, glass powder, alumina, calcium carbonate, calcium sulfate, talc, boron silicate and the like. These may be used alone or in combination of two or more in any combination and blending ratio. Among these, crushed and / or spherical, molten and / or crystalline silica powder fillers are preferred when used for semiconductor encapsulation.

By using the inorganic filler, when the epoxy resin composition is used as the semiconductor encapsulant, the coefficient of thermal expansion of the semiconductor encapsulant can be brought close to that of the internal silicon chip or lead frame, and the semiconductor encapsulant can be used. Since the amount of moisture absorbed by the entire stopper can be reduced, the solder crack resistance can be improved.

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 more than the above lower limit value, the melt viscosity does not become too high and the fluidity does not easily decrease. Therefore, when the average particle size is equal to or less than the above upper limit value, a narrow gap in the mold is formed during molding. This is preferable because the filler is less likely to be clogged and the filling property of the material is easily improved.

When an inorganic filler is used in the epoxy resin composition of the present invention, the inorganic filler is preferably blended in the range of 60 to 95% by weight of the entire epoxy resin composition.

[Release agent]
A mold release agent can be added to the epoxy resin composition of the present invention. As the release agent, for example, a natural wax such as carnauba wax, a synthetic wax such as polyethylene wax, higher fatty acids such as stearic acid and zinc stearate and their metal salts, and a hydrocarbon-based release agent such as paraffin should be used. Can be done. These may be used alone or in combination of two or more in any combination and blending ratio.

When the mold release agent is blended in the epoxy resin composition of the present invention, the blending amount of the mold release agent is preferably 0.1 to 5.0 with respect to 100 parts by weight of all the epoxy resin components in the epoxy resin composition. It is by weight, more preferably 0.5 to 3.0 parts by weight. When the blending amount of the release agent is within the above range, it is preferable because good releasability can be exhibited while maintaining the curing characteristics of the epoxy resin composition.

[Coupling agent]
It is preferable to add a coupling agent to the epoxy resin composition of the present invention. The coupling agent is preferably used in combination with the inorganic filler, and by blending the coupling agent, the adhesiveness between the epoxy resin as a matrix and the inorganic filler can be improved. Examples of the coupling agent include a silane coupling agent and a titanate coupling agent.

Examples of the silane coupling agent include epoxysilanes such as γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, and γ-. Aminopropyltriethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, γ-aminopropyltrimethoxysilane, γ-ureidopropyltriethoxy Aminosilane such as silane, mercaptosilane such as 3-mercaptopropyltrimethoxysilane, p-styryltrimethoxysilane, vinyltricrolsilane, vinyltris (β-methoxyethoxy) silane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacry Examples thereof include vinyl silanes such as loxypropyltrimethoxysilane, and epoxy-based, amino-based, and vinyl-based polymer-type silanes.

Examples of the titanate coupling agent include isopropyltriisostearoyl titanate, isopropyltri (N-aminoethyl / aminoethyl) titanate, diisopropylbis (dioctylphosphate) titanate, tetraisopropylbis (dioctylphosphate) titanate, and tetraoctylbis (dioctylphosphate). Ditridecylphosphite) titanate, tetra (2,2-diallyloxymethyl-1-butyl) bis (ditridecyl) phosphite titanate, bis (dioctylpyrophosphate) oxyacetate titanate, bis (dioctylpyrophosphate) ethylene titanate, etc. Be done.

Any of these coupling agents may be used alone, or two or more thereof may be mixed and used in any combination and ratio.

When a coupling agent is used in the epoxy resin composition of the present invention, the blending amount thereof is preferably 0.1 to 3.0 parts by weight with respect to 100 parts by weight of all the epoxy resin components. When the blending amount of the coupling agent is equal to or higher than the above lower limit value, the effect of improving the adhesion between the epoxy resin, which is a matrix, and the inorganic filler due to the blending of the coupling agent tends to be improved, while the coupling When the blending amount of the agent is not more than the above upper limit value, the coupling agent is less likely to bleed out from the obtained cured product, which is preferable.

[Other ingredients]
In the epoxy resin composition of the present invention, components other than those described above (may be referred to as "other components" in the present invention) can be blended. Examples of other components include flame retardants, plasticizers, reactive diluents, pigments and the like, which can be appropriately blended as needed. However, the epoxy resin composition of the present invention does not prevent the blending of components other than those listed above.

The flame retardants used in the epoxy resin composition of the present invention include halogen-based flame retardants such as brominated epoxy resin and brominated phenol resin, antimony compounds such as antimon trioxide, red phosphorus, phosphate esters, phosphines and the like. Examples thereof include phosphorus-based flame retardants, nitrogen-based flame retardants such as melamine derivatives, and inorganic flame retardants such as aluminum hydroxide and magnesium hydroxide.

[Cured product]
By curing the epoxy resin composition of the present invention, the cured product of the present invention can be obtained. The cured product of the present invention obtained by curing the epoxy resin composition of the present invention has excellent properties in heat resistance, moisture absorption resistance, and particularly heat resistance.

The method for curing the epoxy resin composition of the present invention is not particularly limited, but usually, a cured product can be obtained by a thermosetting reaction by heating. At the time of the thermosetting reaction, it is preferable to appropriately select the curing temperature depending on the type of the curing agent used. For example, when a phenolic curing agent is used, the curing temperature is usually 130 to 300 ° C. Further, by adding a curing accelerator to these curing agents, it is possible to lower the curing temperature. The reaction time is preferably 1 to 20 hours, more preferably 2 to 18 hours, still more preferably 3 to 15 hours. When the reaction time is at least the above lower limit value, the curing reaction tends to proceed sufficiently, which is preferable. On the other hand, when the reaction time is not more than the above upper limit value, deterioration due to heating and energy loss during heating can be easily reduced, which is preferable.

The epoxy resin composition of the present invention has excellent heat resistance, and can preferably give a cured product having a glass transition temperature (Tg) of 115 ° C. or higher. The higher the glass transition temperature of the cured product, the less thermal stress is applied to the sealed resin when it is used as a semiconductor encapsulant, and it is less likely to cause defects such as passivation, chip damage, aluminum wiring slides, and package cracks. Is preferable.
Here, the glass transition temperature (Tg) is measured by the method described in the section of Examples described later.

[Use]
The epoxy resin (1) of the present invention has a small amount of hydrolyzable chlorine and is excellent in solvent solubility, and the epoxy resin composition of the present invention containing the epoxy resin (1) of the present invention is excellent in heat resistance and the like. Therefore, the epoxy resin and the epoxy resin composition of the present invention can be effectively used in any application as long as these physical properties are required. For example, in the field of paints such as electrodeposition paints for automobiles, heavy-duty anticorrosion paints for ships and bridges, paints for inner surface coating of beverage cans, and electrical and electronic products for laminates, semiconductor encapsulants, insulating powder paints, coil impregnations, etc. Suitable for all fields, such as seismic reinforcement of bridges, concrete reinforcement, flooring of buildings, lining of water supply facilities, drainage / water permeable pavement, civil engineering / construction / adhesive field of vehicle / aircraft adhesives, etc. be able to. Among these, it is particularly useful for electrical and electronic applications such as semiconductor encapsulants and laminated plates.

The epoxy resin composition of the present invention may be used after curing for the above-mentioned application, or may be cured in the manufacturing process of the above-mentioned application.

Hereinafter, the present invention will be described in more detail based on Examples, but the present invention is not limited to the following Examples. The values of various production conditions and evaluation results in the following examples have meanings as preferable values of the upper limit or the lower limit in the embodiment of the present invention, and the preferable range is the above-mentioned upper limit or lower limit value. , The range may be defined by the combination of the values of the following examples or the values of the examples.

[Manufacturing and evaluation of epoxy resin 1]
[Manufacturing Example 1]
Tetramethylbiphenol (2) (manufactured by Mitsubishi Chemical Corporation) 137 g, epichlorohydrin 627 g, isopropyl alcohol 244 g, and water 87 g were charged into a 2 L four-necked flask equipped with a thermometer, agitator, and a cooling tube, and heated to 65 ° C. After the temperature was raised to uniformly dissolve the mixture, 108 g of a 48.5 wt% sodium hydroxide aqueous solution was added dropwise over 90 minutes. After completion of the dropping, hold at 65 ° C. for 30 minutes to complete the reaction, transfer the reaction solution to a 3 L separatory funnel, allow it to stand at 65 ° C. for 1 hour, and then extract the aqueous layer from the separated oil layer and aqueous layer to prepare a secondary solution. Raw salt and excess sodium hydroxide were removed. Then, excess epichlorohydrin and isopropyl alcohol were distilled off from the product under reduced pressure to obtain a crude epoxy resin.

This crude epoxy resin was dissolved in 300 g of methyl isobutyl ketone, 4 g of a 48.5 wt% sodium hydroxide aqueous solution was added, and the reaction was carried out again at a temperature of 65 ° C. for 1 hour. Then, after adding 167 g of methyl isobutyl ketone, washing with water was performed 4 times with 500 g of water. Then, methyl isobutyl ketone was completely removed under a reduced pressure of 150 ° C. to obtain an epoxy equivalent of 185 g / equivalent.

[Manufacturing Example 2]
Tetramethylbiphenol (2) (manufactured by Mitsubishi Chemical Corporation) 0.5 mol, epichlorohydrin 4 mol, tetramethylammonium chloride in tetramethylbiphenol in a 2 L four-necked flask equipped with a thermometer, agitator, and cooling tube. Add 2 times by weight to (2) and carry out the reaction under the same reaction conditions as in Example 1 of Patent Document 1 described above. Similarly, after recovering epichlorohydrin, add 500 ml of toluene and wash with 1 L of water 3 times. Then, toluene was removed under reduced pressure to obtain an epoxy equivalent of 202 g / equivalent of epoxy resin.

[Example 1]
100 g of the epoxy resin, 120 g of methyl isobutyl ketone, and 30 g of dimethyl sulfoxide obtained in Production Example 1 were charged into a 2-L four-necked flask equipped with a thermometer, a stirrer, and a cooling tube, and the reaction temperature was raised to 65 ° C. After uniformly dissolving, 9.7 g of an 8 wt% potassium hydroxide / isopropanol solution was added, and the reaction was carried out for 1 hour. Then, after adding 112 g of methyl isobutyl ketone, washing with water was performed 4 times with 200 g of water. Then, methyl isobutyl ketone was completely removed under a reduced pressure of 150 ° C. to obtain an epoxy resin.

[Example 2]
An epoxy resin was obtained in the same manner as in Example 1 except that the amount of the 8 wt% potassium hydroxide / isopropanol solution added was 8.7 g and the reaction temperature was changed to 60 ° C.

[Example 3]
An epoxy resin was obtained in the same manner as in Example 1 except that the amount of the 8 wt% potassium hydroxide / isopropanol solution added was 10.7 g and the reaction temperature was changed to 80 ° C.

[ Comparative Example 9 ]
100 g of the epoxy resin, 80 g of methyl isobutyl ketone, and 20 g of dimethyl sulfoxide obtained in Production Example 1 were charged into a 2-L four-necked flask equipped with a thermometer, a stirrer, and a cooling tube, and the reaction temperature was raised to 65 ° C. After uniformly dissolving, 2.0 g of an 8 wt% potassium hydroxide / isopropanol solution was added, and the reaction was carried out for 1 hour. Then, after adding 162 g of methyl isobutyl ketone, washing with water was performed 4 times with 200 g of water. Then, methyl isobutyl ketone was completely removed under a reduced pressure of 150 ° C. to obtain an epoxy resin.

[Comparative Example 1]
The epoxy resin synthesized in Production Example 1 was used.

[Comparative Example 2]
An epoxy resin was obtained in the same manner as in Example 1 except that the amount of the 8 wt% potassium hydroxide / isopropanol solution added was changed to 2.4 g.

[Comparative Example 3]
An epoxy resin was obtained in the same manner as in Example 1 except that the amount of the 8 wt% potassium hydroxide / isopropanol solution added was 15.0 g and the reaction temperature was changed to 80 ° C.

[Comparative Example 4]
The epoxy resin synthesized in Production Example 2 was used.

[Comparative Example 5]
100 g of the epoxy resin, 80 g of methyl isobutyl ketone, and 20 g of dimethyl sulfoxide obtained in Production Example 1 were charged into a 2-L four-necked flask equipped with a thermometer, a stirrer, and a cooling tube, and the reaction temperature was raised to 65 ° C. After uniformly dissolving, 2.4 g of a 48 wt% sodium hydroxide aqueous solution was added, and the reaction was carried out for 1 hour. Then, after adding 162 g of methyl isobutyl ketone, washing with water was performed 4 times with 200 g of water. Then, methyl isobutyl ketone was completely removed under a reduced pressure of 150 ° C. to obtain an epoxy resin.

Epoxy equivalent, hydrolyzable chlorine amount, melt viscosity at 150 ° C., weight average molecular weight (Mw), and number average molecular weight (Mn) of the epoxy resins obtained in Examples 1 to 3 and Comparative Examples 1 to 5 and Comparative Example 9. ) Was measured by the method described above, and the following solvent solubility test was performed, and the results are shown in Table 1.

[Solvent solubility test]
Toluene, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), or acetone was used as the test solvent, and an epoxy resin was added to each solvent so as to have a predetermined resin concentration (40% by weight or 20% by weight), respectively. The test solution was prepared, and 20 ml of the test solution was weighed in a 50 ml vial. Then, after heating to completely dissolve the epoxy resin, it is stored at a predetermined temperature (23 ° C. or 5 ° C.), and those in which no crystals are precipitated within one month are excellent in solvent solubility "○". Those in which less than 25% by weight of crystals were precipitated were evaluated as having good solvent solubility "Δ", and those in which crystals were precipitated in an amount of 25% by weight or more were evaluated as having poor solvent solubility "x".

[Manufacturing and evaluation of epoxy resin composition 1]
[Examples 5 to 7 and Comparative Examples 6 to 8]
The epoxy resin and the curing agent were mixed at the ratios shown in Table 2, heated to 100 ° C., and stirred until uniform. Then, the mixture was cooled to 80 ° C., a curing accelerator was added at the ratio shown in Table 2 and stirred until uniform to prepare an epoxy resin composition. In Table 2, "part" represents "part by weight".

The curing agent and curing accelerator used are as follows.
Hardener: Phenol aralkyl resin (trade name MEH7800 manufactured by Meiwa Kasei Co., Ltd. (hydroxyl equivalent: 174 g / equivalent))
Curing accelerator: Triphenylphosphine (trade name: triphenylphosphine manufactured by Tokyo Chemical Industry Co., Ltd.)

Two glass plates on which a release pet film was laminated were prepared on one surface, and these glass plates were used with the release pet film side as the inner surface, and the distance between the glass plates was adjusted to 4 mm to prepare a casting plate.
The epoxy resin composition was cast into the casting plate and cured by heating at 120 ° C. for 2 hours and then at 175 ° C. for 6 hours to obtain a cured product.

The glass transition temperature of the obtained cured product was measured by the following method as an evaluation of heat resistance, and the results are shown in Table 2.

[Measurement of glass transition temperature (Tg (E'')]
A test piece was obtained by cutting the cured product into a length of 5 cm, a width of 1 cm, and a thickness of 4 mm. Analysis was performed by a thermomechanical analyzer (DMS: EXSTAR6100 manufactured by Seiko Instruments Inc.) in the three-point bending mode by the following measurement method, and the peak top of E'' at 1 Hz was defined as Tg (E'').
(Measuring method)
1st temperature rise: 5 ° C / min, 30 ° C to 250 ° C

[Evaluation of results]
From Table 1, it can be seen that the epoxy resins of Examples 1 to 3 and Comparative Example 9 are all excellent in solvent solubility with respect to the epoxy resins of Comparative Examples 1 to 2 and 4 to 5.

Further, from Table 2, the epoxy resin cured products of Examples 5 to 7 have the same heat resistance as the epoxy resin cured products of Comparative Examples 6 and 7, and are more heat resistant than the epoxy resin cured products of Comparative Example 8. It turns out to be excellent.

Claims (7)

Represented by the following formula (1), the number-average molecular weight (Mn) of 270 to 460, a weight average molecular weight (Mw) of from 370 to 6080, the content of hydrolyzable chlorine Ri der less 90 ppm, an epoxy equivalent 200～255G / eq der Ru epoxy resin.

(In the formula, n represents an integer from 0 to 10.) The epoxy resin according to claim 1, wherein the melt viscosity at 150 ° C. is 3.0 Pa · s or less. An epoxy resin composition containing 0.1 to 1000 parts by weight of a curing agent with respect to 100 parts by weight of the epoxy resin according to claim 1 or 2 . The epoxy resin composition according to claim 3 , 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. Claim 1 or epoxy resin composition according to claim 3 or claim 4 further comprising a different epoxy resin as the epoxy resin of claim 2. A cured product obtained by curing the epoxy resin composition according to any one of claims 3 to 5 . An electrical / electronic component obtained by curing the epoxy resin composition according to any one of claims 3 to 5 .