KR101522346B1 - Epoxy resin composition and cured product - Google Patents

Abstract

An epoxy resin composition which exhibits excellent fluidity, exhibits heat resistance and low thermal expansion, and is useful for semiconductor encapsulating materials, molding materials, laminated materials, powder coating materials and adhesive materials.
This epoxy resin composition comprises an epoxy resin, a curing agent for an epoxy resin, and an inorganic filler, and an epoxy resin having a diepoxyethylbenzene structure is used as the epoxy resin. The epoxy resin is a 1,3- And 90% by weight or more of a 4-disubstituent, the viscosity at 25 캜 is 50 mPa s or less, and the curing agent for an epoxy resin is a polyhydric hydroxy compound.

Description

[0001] EPOXY RESIN COMPOSITION AND CURED PRODUCT [0002]

The present invention relates to an epoxy resin composition useful as an encapsulating material, a coating material, a lamination material, a composite material, etc. for electrical and electronic parts, which is excellent in low viscosity and excellent in heat resistance and low thermal expansion, As the cured product, it is suitably used for a printed wiring board, an insulating material for electrical and electronic fields such as a semiconductor bag, and a carbon fiber-reinforced composite material.

BACKGROUND ART Epoxy resins have been used industrially for a wide variety of applications, and their required performance has recently been advanced. For example, semiconductor encapsulating materials have been used in representative examples of resin compositions using epoxy resin as a main agent. Recently, as the degree of integration of semiconductor devices has been improved, package sizes have become larger and thinner, The development to the wire has progressed, and development of a material excellent in heat resistance of the solder is desired.

In recent years, in accordance with the trend of high integration and high-density mounting technology, a hybrid IC, a chip on board, a tape carrier package, a plastic pin grid array, There has been an increase in the number of mounting methods using a liquid material without using a mold such as a plastic ball grid array. Generally, however, the liquid material has a lower reliability than the solid material used in the transfer molding. This is because the viscosity of the liquid material is limited and there are restrictions on the resin, curing agent, filler, etc. used.

As a matrix resin of a carbon fiber-reinforced composite material, an epoxy resin excellent in moldability, heat resistance and mechanical characteristics is desired. In recent years, there has been a growing demand for compatibility between low viscosity and high internal resistance in applications such as automobile parts, railroad cars, and aircraft.

As the low-viscosity epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin and the like are generally widely known, but they are not sufficient in terms of low viscosity and heat resistance. As an epoxy resin excellent in low viscosity, an epoxy resin having an oxymethylene chain has been proposed in JP-A-4-359009, but it is not sufficient in heat resistance.

On the other hand, US 2924580 discloses an example of an epoxy resin composition using epoxyethylbenzene which is an epoxide of divinylbenzenes, and an example of the epoxy resin composition is shown. However, detailed physical properties of the epoxy resin cured product are not examined here, and the performance of practical properties is not known.

Japanese Patent Application Laid-Open No. 4-359009 US 2924580 specification

Accordingly, an object of the present invention is to provide an epoxy resin composition which is excellent in low viscosity and excellent in heat resistance, low thermal expansion, and the like, and a cured product thereof.

That is, the present invention provides an epoxy resin composition comprising an epoxy resin and a curing agent for an epoxy resin, wherein the epoxy resin is represented by the following general formula (1)

(Wherein R is a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, and n is 4 and all may be the same or different), and the substitution positions of the two epoxyethyl groups are 1,3-disubstituted and 1 , An epoxy compound as a 4-disubstituted compound in an amount of 90 wt% or more in total, and having a viscosity at 25 캜 of 50 mPa s or less is used, and the viscosity of the composition (excluding inorganic filler) In the range of 0.01 to 100 Pa · s.

In the epoxy resin represented by the general formula (1), it is preferable that the ratio (molar ratio) of the 1,3-di substituted compound to the 1,4-di substituted compound in the epoxy ethyl group is in the range of 1: 9 to 9: 1. The curing agent for epoxy resins is preferably a polyhydric hydroxy compound. The epoxy resin composition may contain an inorganic filler, and the content of the inorganic filler in the case may be 83 wt% or more.

The present invention also relates to the above-mentioned epoxy resin composition for encapsulating electric and electronic parts, and an epoxy resin cured product obtained by curing the above epoxy resin composition.

According to the present invention, it is possible to provide an epoxy resin composition that exhibits excellent fluidity, exhibits heat resistance and low thermal expansion, and is useful for a semiconductor encapsulant, a molding material, a laminate material, a powder coating material, and an adhesive material.

Hereinafter, the present invention will be described in detail.

The epoxy resin composition of the present invention contains an epoxy resin and a curing agent for an epoxy resin as essential components, and these essential components are used as a main component of the resin component. The epoxy resin composition of the present invention may contain an inorganic filler. In this case, the epoxy resin composition comprises the essential component and an inorganic filler as main components.

The epoxy resin used in the epoxy resin composition of the present invention is represented by the above general formula (1). The epoxy resin of the general formula (1) has a structure in which two epoxyethyl groups are substituted in the benzene skeleton, and the isomers include 1,2-di-substituted, 1,3-di-substituted and 1,4-di-substituted. The epoxy resin used in the present invention may be a mixture of these isomers, but a high content ratio of 1,3-di-substituent and 1,4-di-substituent is preferable from the viewpoint of compatibility between heat resistance and low viscosity, Preferably 95% by weight or more, of 1,3-di-substituted and 1,4-di-substituted. A high content of 1,2-di-substituents does not sufficiently exhibit high heat resistance.

The epoxy resin represented by the general formula (1) is preferably in the range of 1: 9 to 9: 1 in terms of the ratio (molar ratio) of the 1,3-di substituted compound to the 1,4-di substituted compound, Is in the range of 3: 7 to 7: 3, more preferably in the range of 4: 6 to 6: 4. For example, when the ratio (molar ratio) of the 1,3-di-substituent is higher than the above range, the heat resistance may not be sufficiently exhibited. In addition, the ratio of the 1,4- , There is a case where the epoxy resin composition exhibits crystallinity and the handling property as a liquid epoxy resin composition is poor.

The viscosity of the epoxy resin represented by the general formula (1) at 25 占 폚 is 50 mPa 占 퐏 or less, and more preferably 30 mPa 占 퐏 or less. If the viscosity at 25 ° C is higher than 50 mPa · s, the viscosity of the epoxy resin composition increases, which is disadvantageous in terms of fluidity at the time of molding and high filling ratio of the inorganic filler, and the performance such as fluidity and low linear expansion property is expected to be improved I can not. Hereinafter, the epoxy resin represented by the general formula (1) having the above characteristics is also referred to as an epoxy resin of the general formula (1).

The epoxy resin represented by the general formula (1) is obtained by subjecting a vinyl group to epoxidation using a divinylbenzene. For example, the desired epoxy resin can be obtained by subjecting divinylbenzenes to an oxidation reaction using an organic peroxide or an oxidizing agent such as hydrogen peroxide. In the general formula (1), R is H or a hydrocarbon group having 1 to 8 carbon atoms, preferably H or a methyl group or an ethyl group. When they are epoxidized by oxidizing divinylbenzenes, they are derived from divinylbenzenes used as raw materials. From the viewpoint of the availability of divinylbenzenes and the properties of the obtained epoxy resin, it is preferable that all of R is hydrogen, 1 or 2 of R is a methyl group or ethyl group, and the others are H. The divinylbenzenes referred to herein means a mixture of isomers of such substituted or unsubstituted divinylbenzene. The blending ratio of the isomers of divinylbenzene is preferably approximately the same as the blending ratio of the isomers of the epoxy resin.

In the epoxidation reaction, examples of the oxidizing agent to be used include organic peroxides such as organic peroxides, organic peroxides, hydroperoxides, peroxide esters and diacyl peroxides, and hydrogen peroxide.

When organic peroxides are used as organic peroxides, there are exemplified peroxy formic acid, peracetic acid, propionic acid, m-chlorobenzoic acid and the like.

The organic peracetic acid may be used in combination with a catalyst. For example, an alkali such as sodium carbonate or an acid such as sulfuric acid may be used as a catalyst.

Examples of the organic peroxide used as the organic peroxide include di tert-butyl peroxide, bistriphenyl methyl peroxide, dicumyl peroxide and the like.

When hydroperoxide is used as the organic peroxide, tert-butyl hydroperoxide, cumene hydroperoxide, triphenylmethyl hydroperoxide and the like are exemplified.

Butyl ester, tert-butyl peracetate, tert-butyl tertiary butyl isobutyrate, tert-butyl benzoate and tert-butyl p-nitrobenzoate are exemplified.

When diacyl peroxide is used as the organic peroxide, examples include lauroyl peroxide, benzoyl peroxide, acetyl peroxide, propionyl peroxide and the like.

When hydrogen peroxide is used as the oxidizing agent, tungstic acid, molybdic acid, heteropoly acid or the like may be used as a catalyst, or a part or all of the protons of these acids may be treated with at least one selected from the group consisting of organic quaternary ammonium salts, alkali metals and alkaline earth metals A salt substituted with a species is preferably used as the catalyst.

The amount (molar ratio) of the oxidizing agent and the divinylbenzene in the epoxidation reaction is not particularly limited, but is, for example, in the range of 0.1 to 20, more preferably in the range of 0.1 to 10.

The reaction temperature is not particularly limited and may be in a range of an allowable range. It is preferable that the temperature range in which the epoxidation reaction proceeds preferentially over the decomposition reaction and the side reaction of the oxidant. The temperature range is, for example, in the range of -30 to 200 占 폚, and more preferably in the range of -10 to 100 占 폚.

The epoxidation reaction may be carried out using a solvent as required. When a solvent is used, for example, aromatic solvents such as toluene and xylene, halogen solvents such as chloroform and dichloromethane chlorobenzene, ester solvents such as ethyl acetate and butyl acetate, ketone solvents such as acetone and methyl ethyl ketone , An ether compound such as dioxane, a polar solvent such as acetonitrile, or a mixed solvent of two or more of these solvents. The amount of the solvent to be used can be set arbitrarily.

The epoxy resin thus obtained may contain a small amount of impurities derived from reaction raw materials or impurities derived from reaction by-products. It is preferable to keep them at 20 wt% or less, preferably 10 wt% or less. The epoxy resin may contain an oligomerized epoxy group in the resin as an ether bond. However, since the viscosity of the epoxy resin increases as the amount of the oligomer component increases, the epoxy resin needs to have a molecular weight at 25 ° C of 50 mPa · s or less.

The amount of the hydrolyzable chlorine of the epoxy resin used in the present invention is preferably as small as possible from the viewpoint of improving the reliability of the electronic component to be encapsulated. But is preferably 50 ppm or less, and more preferably 10 ppm or less. The term " hydrolyzable chlorine " in the present invention means a value measured by the following method. That is, after dissolving 0.5g of a sample in 30ml of dioxane, then a 1N-KOH refluxed for 30 min in 10ml ratio was added, and allowed to cool to room temperature, and 80% by the addition of 100ml acetone,-0.002N AgNO ₃ solution to the potential difference Is a value obtained by performing titration.

The epoxy resin component used in the present invention can be used in combination with other epoxy resin for known purpose in addition to the epoxy resin of the general formula (1) within the range not impairing the effect of the present invention. Examples of other epoxy resins include bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, 2,2'-biphenol, 3,3 ', 5,5'-tetramethyl-4,4'-dihydroxybis (4-hydroxyphenyl) methane, 1,1,2,2-tetrakis (4-hydroxyphenyl) ethane, phenol novolak, , o-cresol novolak, epoxides of cocondensation resins of dicyclopentadiene and phenols, epoxides of phenol aralkylphosphates synthesized from phenols and paraxylylene dihydrochloride, phenols such as phenols Epoxides of biphenyl aralkyl type phenol resins synthesized from bischloromethyl biphenyl and the like, and epoxides of naphthol aralkyl type ones synthesized from naphthols and p-xylylene dihydrochloride. These other epoxy resins may be used in combination of two or more. When these other epoxy resins are used in combination, the amount of the epoxy resin used is preferably 50 wt% or less, advantageously 20 wt% or less of the total epoxy resin.

As the curing agent for an epoxy resin used in the epoxy resin composition of the present invention, any compound commonly used as a curing agent for an ordinary epoxy resin can be used, and aliphatic amines such as diethylenetriamine and triethylenetetramine, , Aromatic amines such as diaminodiphenylmethane and diaminodiphenylsulfone, polyhydric hydroxy compounds such as phenol novolak resin, orthocresol novolak resin, naphthol novolak resin and phenol aralkyl resin, and modified products thereof, Acid anhydride-based curing agents such as phthalic anhydride, maleic anhydride, hexahydrophthalic anhydride and pyromellitic anhydride, latent curing agents such as dicyandiamide, imidazole, BF ₃ -amine complexes and guanidine derivatives.

Among them, a polyhydric hydroxy compound suitable for a semiconductor encapsulating material is preferably used. Specific examples thereof include divalent phenols such as bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, 4,4'-biphenol, 2,2'-biphenol, hydroquinone, resorcin, catechol and naphthalene diols , Tris- (4-hydroxyphenyl) methane, 1,1,2,2-tetrakis (4-hydroxyphenyl) ethane, phenol novolak, o-cresol novolak, naphthol novolac, Phenols, naphthols or bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, 4,4'-biphenol, 2,2'-biphenol, hydroquinone, resorcin, catechol, Naphthalene diol and the like and a divalent phenol such as formaldehyde, acetaldehyde, benzaldehyde, p-hydroxybenzaldehyde, p-xylylene glycol, p-xylylene glycol dimethyl ether, divinylbenzene, diisopropenylbenzene, And a cross-linking agent such as ethoxy methyl biphenyl, divinyl biphenyl, diisopropenyl biphenyl, etc. In which, and the like polyhydric hydroxy compound synthesized.

The softening point of the polyhydric hydroxy compound is preferably 40 to 150 캜, more preferably 50 to 120 캜. If the temperature is lower than 40 占 폚, for example, when the epoxy resin composition is filled with an inorganic material, the viscosity becomes too low to cause precipitation of the inorganic material. If the temperature is higher than 150 占 폚, there is a problem in mixing kneading and molding property at the time of preparing the epoxy resin composition. The melt viscosity at 150 캜 is preferably 1 Pa · s or less, and more preferably 0.5 Pa · s or less. When the viscosity is higher than 1 Pa · s, there is a problem in mixing kneading property and moldability at the time of preparation of the epoxy resin composition. However, when the epoxy resin composition (including no inorganic filler) has a viscosity of 0.01 to 100 Pa · s . Here, an epoxy resin composition (not including an inorganic filler) refers to a composition comprising all the epoxy resin to be mixed with the epoxy resin composition and the entire curing agent.

The epoxy resin composition of the present invention preferably has a low viscosity in order to blend an inorganic filler at a high content. Therefore, the viscosity of the epoxy resin composition in the state where the inorganic filler is removed from the epoxy resin composition is set to 0.01 to 100 Pa · s, preferably 1 to 100 Pa · s at 25 ° C.

The epoxy resin composition of the present invention may contain an inorganic filler. The epoxy resin composition containing the inorganic filler is suitable for sealing. Examples of the inorganic filler include silica, alumina, zircon, calcium silicate, calcium carbonate, silicon carbide, silicon nitride, boron nitride, zirconia, fosterite, stearate, spinel, mullite, titania, Two or more kinds of them may be used in combination, and it is preferable to use fused silica as a main component, and the form thereof may be crushed or spherical. Generally, silica is used in combination with several kinds of particles having a particle diameter distribution. The average particle diameter of the silica to be combined is preferably 0.5 to 100 mu m. When the inorganic filler is blended, the content is preferably 83% by weight or more, and more preferably 83 to 90% by weight. If it is less than 83% by weight, the content of the organic component increases, and moisture resistance and low linear expansion properties are not sufficiently exhibited.

In the epoxy resin composition of the present invention, an oligomer or a high molecular compound such as a polyester, a polyamide, a polyimide, a polyether, a polyurethane, a petroleum resin, an indenkumarone resin, or a phenoxy resin can be appropriately compounded , Pigments, flame retardants, thixotropic agents, coupling agents, flowability improvers, and the like. Examples of the pigment include an organic or inorganic extender pigment, a scaly pigment, and the like. Examples of the thixotropic agent include a silicone type, a castor oil type, an aliphatic amide wax, an oxidized polyethylene wax, and an organic bentonite type. If necessary, curing accelerators such as amines, imidazoles, organic phosphines and Lewis acids can be added. The blending amount of the curing accelerator is usually 0.2 to 5 parts by weight based on 100 parts by weight of the epoxy resin. If necessary, the resin composition of the present invention may contain a releasing agent such as carnauba wax and OP wax, a coupling agent such as? -Glycidoxypropyltrimethoxysilane, a coloring agent such as carbon black, a flame retardant such as antimony trioxide, Low-stressing agents such as oil, lubricants such as calcium stearate, and the like.

The cured product of the present invention can be obtained by curing the epoxy resin composition by a molding method such as casting, compression molding, or transfer molding. The temperature at which the cured product is produced is usually 120 to 220 ° C.

<Examples>

Hereinafter, the present invention will be described in detail based on Synthesis Examples, Examples and Comparative Examples.

(Synthesis Example 1)

A 3 L reactor was charged with 300 g of divinylbenzene (DVB-960 divinylbenzene content 97%, m-isomer / p-isomer = 62: 38, manufactured by Shinnitetsuga Kagaku Co., Ltd.) and 1200 g of ethyl acetate. Subsequently, 1640 g of a 30% acetic acid ethyl acetate solution was added dropwise over 3 hours. The dropping was controlled so that the reaction temperature was 30 ° C. After the dropwise addition, stirring was further carried out at 30 DEG C for 3 hours. After the reaction solution was cooled to room temperature, 1208 g of 20% NaOH aqueous solution was added and stirred for 1 hour, and the aqueous layer was separated to remove unreacted peracetic acid and produced acetic acid. Ethyl acetate was distilled off under reduced pressure using an evaporator to obtain 151.6 g of diepoxyethylbenzene (epoxy resin a). The epoxy equivalent of the obtained resin was 111 g / eq. The viscosity at 25 占 폚 was 10 mPa 占 퐏, the purity was 94.3% (gas chromatographic area%), and the m- and p-isomers were 64:36 ( ¹ H-NMR).

(Synthesis Example 2)

65 g of hydroquinone, 546 g of epichlorohydrin and 82 g of diethylene glycol dimethyl ether were placed in a four-neck separable flask and dissolved by stirring. After uniformly dissolving, 98.4 g of a 48% sodium hydroxide aqueous solution was added dropwise at 65 ° C under a reduced pressure of 130 mmHg for 4 hours, and water and epichlorohydrin, which had been refluxed and distilled in the dropwise addition, ), Epichlorohydrin was returned to the reaction vessel, and water was removed from the system and reacted. After completion of the reaction, the resulting salt was removed by filtration, and after washing with water, epichlorohydrin was distilled off to obtain 120 g of an epoxy resin (epoxy resin b). The obtained epoxy resin had an epoxy equivalent of 116 g / eq. And a melting point of 100 캜.

(Example 1, Comparative Examples 1 and 2)

An epoxy resin composition was prepared by mixing and kneading the epoxy resin, curing agent and inorganic filler shown below and triphenylphosphine as a curing accelerator at the mixing ratios shown in Table 1 below.

The hydroquinone type epoxy resin b obtained in Synthesis Example 2 and the epoxy resin c (bisphenol F type epoxy resin, YDF-170 manufactured by Tohto Kasei Co., Ltd.) as comparative epoxy resin a obtained in Synthesis Example 1, ; Epoxy equivalent: 167 g / eq. Viscosity at 25 캜: 2.9 Pa · s) was used.

PN (phenol novolac resin, PSM-4261, OH equivalent: 103, softening point: 82 占 폚, manufactured by Gunegai Kagaku Co., Ltd.) was used as a curing agent component.

Spherical fused silica FB-60 (average particle diameter of 21 mu m) and FB-35 (mean particle diameter of 12 mu m) manufactured by Denki Kagaku Kogyo K.K., spherical fused silica SO-C3 manufactured by Adomatex Average particle diameter: 0.9 占 퐉) and SO-C2 (average particle diameter: 0.5 占 퐉) were mixed and used.

The composition of the composition obtained by mixing the epoxy resin and the curing agent (without the filler and the curing accelerator) was measured by using an E-type viscometer at 25 ° C, and the results are shown in Table 1.

The epoxy resin composition obtained by mixing the epoxy resin composition with a filler was measured for spiral flow and gel time. With respect to the spiral flow, the epoxy resin composition was molded under the injection pressure (150 kgf / cm ² ) of the spiral flow and the curing time of 3 minutes with a mold for spiral flow measurement conforming to the standard (EMMI-1-66) Respectively. With respect to the gel time, an epoxy resin composition was poured into a concave portion of a gelation tester (product of Nissin Kagaku Kogyo Co., Ltd.) preliminarily heated to 175 ° C, and a Teflon (registered trademark) rod was used at a rate of two revolutions And the gelation time required until the epoxy resin composition hardened was investigated by stirring.

Next, the epoxy resin composition was molded at 175 占 폚 and post-cured at 175 占 폚 for 12 hours to obtain a cured product test piece, which was then subjected to various physical property measurements. The glass transition point was measured by a thermomechanical measuring apparatus at a heating rate of 7 DEG C / min. In the bending test, the bending strength and the bending elastic modulus were measured by a three-point bending method. The water absorption rate is obtained by forming a disk having a diameter of 50 mm and a thickness of 3 mm using the present epoxy resin composition and post-curing and moisture-absorbing at 85 ° C and 85% RH for 100 hours. The results are summarized in Table 1.

The epoxy resin composition of the present invention can give a cured product excellent in low viscosity and excellent in heat resistance and low thermal expansion. The epoxy resin composition of the present invention exhibits excellent fluidity at the time of molding by using an epoxy resin excellent in low viscosity. It is also possible to make the filler low in charge due to the low viscosity. Further, since the epoxy resin component does not have a flexible oxymethylene moiety as compared with the glycidyl ether group possessed by a general epoxy resin, the molecular motion of the cured product is suppressed, and excellent heat resistance and low thermal expansion performance are exhibited. With the excellent fluidity, heat resistance and low thermal expansion property, it can be suitably used for semiconductor encapsulating materials, various molding materials, laminated materials, powder coating materials and adhesive materials. Especially, it is excellent for encapsulating electronic parts.

Claims (6)

An epoxy resin composition comprising an epoxy resin and a curing agent for an epoxy resin, wherein the epoxy resin is represented by the following general formula (1), wherein the substitution positions of the two epoxyethyl groups are 1,3-di- A polyhydric hydroxy compound having a softening point of 40 to 150 DEG C is used as a curing agent for an epoxy resin using an epoxy resin having a total of at least 90% by weight of a substituted epoxy compound and having a viscosity at 25 DEG C of 50 mPa.s or less , And a composition (not including an inorganic filler) having a viscosity of from 0.01 to 100 Pa · s at 25 占 폚.

Here, R is a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, and n is 4, and they may all be the same or different. The method according to claim 1,
Wherein the ratio (molar ratio) of the 1,3-di substituted compound to the 1,4-di substituted compound of the epoxy resin represented by the general formula (1) is in the range of 1: 9 to 9: 1. The method according to claim 1,
Wherein the curing agent for an epoxy resin is a phenol novolak resin. The method according to claim 1,
And an inorganic filler in an amount of 83% by weight or more. The method according to claim 1,
An epoxy resin composition characterized by being encapsulated in an electric or electronic part An epoxy resin cured product obtained by curing the epoxy resin composition according to any one of claims 1 to 5.