WO2019171993A1

WO2019171993A1 - Epoxy resin composition and cured product of same

Info

Publication number: WO2019171993A1
Application number: PCT/JP2019/006964
Authority: WO
Inventors: 昌己大村; 健廣田
Original assignee: 日鉄ケミカル＆マテリアル株式会社
Priority date: 2018-03-09
Filing date: 2019-02-25
Publication date: 2019-09-12
Also published as: JP7252196B2; SG11202008706UA; KR20200130372A; JPWO2019171993A1; CN111819242A; TWI806976B; CN111819242B; TW201938681A

Abstract

Provided are: an epoxy resin composition which enables the achievement of an epoxy resin cured product that has excellent tracking resistance and excellent thermal decomposition stability, while having a good balance between the tracking resistance and heat resistance, and which is suitable especially for power semiconductor sealing; an epoxy resin cured product; and a semiconductor. An epoxy resin composition which contains, as essential components, (A) an epoxy resin represented by general formula (1), (B) a non-aromatic epoxy resin or a non-silicone rubber, which has a 5% weight loss temperature of 260°C or more, (C) a curing agent and (D) a curing accelerator, and which is characterized in that the component (B) is contained in an amount of 1-50% by weight relative to the total amount of the components (A)-(D). In the formula, n represents a number of 0-20; and G represents a glycidyl group.

Description

Epoxy resin composition and cured product thereof

The present invention relates to an epoxy resin composition, an epoxy resin cured product, and a semiconductor device, and more specifically, an epoxy resin cured product excellent in heat resistance and thermal decomposition stability is obtained, and is excellent in tracking resistance. The present invention relates to an epoxy resin composition suitable for semiconductor encapsulation, a cured epoxy resin, and a semiconductor device.

Epoxy resins are used in a wide range of industrial applications. As an example, there is an application as a sealing material in a semiconductor device, but the required performance in the semiconductor device has become increasingly sophisticated in recent years, and the required power density has become a region that is difficult to reach with conventional Si devices. . Under such circumstances, SiC power devices can be cited as devices that are expected to have higher power density and are being developed in recent years. To achieve higher power density, the temperature of the chip surface during operation Reaches 200 ° C or more. Therefore, development of a sealing material that can withstand the temperature and maintain the physical properties for 1000 hours or more is desired.

In particular, in vehicle-mounted semiconductor devices, integration of various sensors and electronic control units that support safety control is progressing, and because it is exposed to heat generation due to heat generation or integration of engines and power modules for a long time, There is a growing demand for materials that can withstand high-temperature environments.

Furthermore, in addition to thermal durability, there is an increasing demand for insulation performance with higher voltages and higher currents. The circuit pitch width and the distance between lead terminals are reduced not only in power semiconductor devices used at high voltages such as in-vehicle, train, wind power generation, and solar power generation, but also in semiconductor packages that are becoming smaller and thinner. In order to secure a spatial distance and a creepage distance for electrically insulating them, the sealing material and the substrate material are required to have a tracking resistance of 600 V or more.

Methods for improving tracking resistance include 1) suppression of thermal / oxidative decomposition (increase of thermal decomposition start temperature, suppression of volatile gas content), 2) improvement of electrical insulation at high temperature (increase of glass transition temperature) 3) It is said that suppressing carbonization (reducing the residual carbon ratio, blending inorganic fillers) is effective, and various methods have been proposed. For example, a semiconductor device (Patent Document 1) encapsulated with a silicone resin as a sealing material having high tracking resistance and excellent processability on the surface, the content of halogen and antimony compounds is 0.1% by weight or less In addition, a flame retardant non-halogen epoxy resin composition excellent in tracking resistance, in which at least one of the curing agents is a polycondensate of a phenol, a compound having a triazine ring or an aldehyde (Patent Document 2), an epoxidized cyclic conjugate There has been proposed a semiconductor chip sealing material (Patent Document 3) which contains a diene polymer as a resin component and may contain an inorganic filler conductive filler. Also, as a resin composition for semiconductor encapsulation having excellent tracking resistance, a resin composition for semiconductor encapsulation containing an alicyclic epoxy resin system having a cyclohexane polyether skeleton and a dicyclopentadiene type phenol resin, which does not contain a benzene skeleton. Although the epoxy resin composition for semiconductor sealing (patent document 5) which mix | blended the metal hydroxide as an inorganic filler with the thing (patent document 4) and an epoxy resin is proposed, heat resistance will fall. On the other hand, an epoxy resin composition for semiconductor encapsulation containing an epoxy resin, a curing agent, an inorganic filler, and a spherical silicone powder (Patent Document 6) is disclosed, but this resin composition attempts to improve tracking resistance. It is not a thing. Furthermore, the sealing resin composition containing the silicone rubber powder (Patent Document 7) is excellent in tracking properties but is not sufficient in heat resistance. Further, there is a concern that the silicone rubber powder may cause contact failure when a low molecular component is volatilized. As a structure having excellent heat resistance, an epoxy resin, an epoxy resin composition and a cured product having a biphenol-biphenylaralkyl structure have already been disclosed, but no tracking resistance has been described (Patent Document 8, Patent Document). 9).

Japanese Patent Laid-Open No. 3-151674 Japanese Patent Laid-Open No. 11-209569 JP 2003-20325 A JP 2005-213299 A JP 2008-143950 A JP 2009-275146 A JP2013-203865A WO2011 / 074517 JP 2013-209503 A

In the conventional technology, since tracking resistance, heat resistance, and flame retardancy are in a trade-off relationship, it is difficult to achieve both heat resistance of 200 ° C. or higher and tracking resistance of 600V. Accordingly, the present invention provides an epoxy resin cured product that is particularly excellent in tracking resistance, excellent in balance with heat resistance, and in thermal decomposition stability. It is intended to provide a cured resin and a semiconductor.

The present invention provides the following components (A) to (D);
(A) an aromatic epoxy resin represented by the following general formula (1),
(B) A modification selected from a non-aromatic epoxy resin or a non-silicone rubber having a 5% weight reduction temperature of 260 ° C. or higher obtained from a TG / DTA measurement at a heating rate of 10 ° C./min under a nitrogen stream. Texture agent,
An epoxy resin composition containing (C) a curing agent and (D) a curing accelerator as essential components, and containing 1 to 50% by weight of component (B) with respect to the total of components (A) to (D) An epoxy resin composition characterized by:

Here, n represents a number from 0 to 20, and G represents a glycidyl group.

The component (B) includes at least one epoxy resin selected from glycidyl esters of divalent aliphatic carboxylic acids having 15 to 64 carbon atoms or glycidyl ethers of divalent aliphatic alcohols having 15 to 64 carbon atoms. Examples thereof include a modifier composed of a bifunctional epoxy resin, or a rubber modifier composed of styrene rubber or acrylic rubber.

As said component (C), the hardening | curing agent containing the phenol resin represented by following General formula (2) is mentioned.

R represents a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, and m represents a number of 0 or 1.

Further, the present invention is a cured epoxy resin obtained by curing the above epoxy resin composition. Furthermore, this invention is a semiconductor device which sealed the semiconductor element with said epoxy resin composition.

According to the present invention, it is possible to provide an epoxy resin composition, a cured epoxy resin, and a semiconductor device that have both tracking resistance and heat resistance, which are difficult with conventional techniques. Moreover, an epoxy resin composition is excellent in fluidity | liquidity and a moldability, and the hardened | cured material is excellent in the glass transition temperature of 200 degreeC or more, long-term thermal stability, and a flame retardance. Furthermore, since it is non-silicone, it is suitable for in-vehicle use.

Hereinafter, the present invention will be described in detail.

The epoxy resin composition of the present invention contains the following components (A) to (D) as essential components. (A) an aromatic epoxy resin represented by the above general formula (1), (B) a modifier selected from a non-aromatic epoxy resin or a non-silicone rubber, (C) a curing agent, and (D ) Cure accelerator.

Component (A) is an epoxy resin represented by the general formula (1), and is also called a biphenyl aralkyl type epoxy resin because it has a biphenyl structure. In the formula, n represents a number from 0 to 20, and G represents a glycidyl group. n is the number of repetitions and represents a number of 0 or more, and the average value (number average) is 1.3 to 20, preferably 1.5 to 15, more preferably 1.7 to 10, more preferably 2 to 6 Is more preferable. In addition, the content of the n = 0 component in which n is 0 is preferably 30% by area or less in terms of gel permeation chromatography (GPC) from the viewpoint of reactivity and fluidity. If it is more than that, the crystallinity becomes strong and handling becomes difficult. Moreover, when using it by melt | dissolving in an organic solvent for laminated board use etc., it is preferable that it is less than 15 area% from a solvent solubility viewpoint, and 10 area% or less is preferable. The content of n = 5 components or more is 15 area% or more from the viewpoint of improving heat resistance, and preferably 20 area% or more. The weight average molecular weight (Mw) measured by GPC is preferably 1,000 to 8,000, more preferably 2,000 to 7,000, and further preferably 2,000 to 5,000.

The epoxy resin can be produced by reacting a polyvalent hydroxy resin represented by the following general formula (3) with epichlorohydrin. Since this polyvalent hydroxy resin has a biphenyl structure, it is also called a biphenyl aralkyl type droxy resin. And this biphenyl aralkyl type hydroxy resin is obtained by reacting biphenols with a biphenyl condensing agent represented by the following general formula (4).

Here, n represents a number from 0 to 20.

X represents a hydroxyl group, a halogen atom or an alkoxy group having 1 to 6 carbon atoms.

Examples of biphenols used as a raw material for synthesizing biphenyl aralkyl type hydroxy resins include 4,4'-dihydroxybiphenyls.

Specific examples of the biphenyl condensing agent include 4,4′-bishydroxymethylbiphenyl, 4,4′-bischloromethylbiphenyl, 4,4′-bisbromomethylbiphenyl, 4,4′-bismethoxymethylbiphenyl. 4,4′-bisethoxymethylbiphenyl. From the viewpoint of reactivity, 4,4′-bishydroxymethylbiphenyl and 4,4′-bischloromethylbiphenyl are preferable. From the viewpoint of reducing ionic impurities, 4,4′-bishydroxymethylbiphenyl, 4 4,4'-bismethoxymethylbiphenyl is preferred.

The molar ratio in the reaction is preferably 1 mol or less for the biphenyl condensing agent to 1 mol of 4,4′-dihydroxybiphenyl, and generally ranges from 0.1 to 0.7 mol. The range is preferably 0.2 to 0.5 mol. If it is less than this, the crystallinity becomes strong, the solubility in epichlorohydrin when synthesizing the epoxy resin is lowered, the melting point of the obtained epoxy resin is increased, and the handleability is lowered. On the other hand, if the amount is larger than this, the crystallinity of the resin is lowered and the softening point and the melt viscosity are increased, which hinders handling workability and moldability.

In addition, when chloromethylbiphenyl is used as the condensing agent, the reaction can be carried out in the absence of a catalyst, but usually the condensation reaction is carried out in the presence of an acidic catalyst. The acidic catalyst can be appropriately selected from known inorganic acids and organic acids. For example, mineral acids such as hydrochloric acid, sulfuric acid, phosphoric acid, formic acid, oxalic acid, trifluoroacetic acid, p-toluenesulfonic acid, metasulfone Examples thereof include organic acids such as acid and trifluorometasulfonic acid, Lewis acids such as zinc chloride, aluminum chloride, iron chloride, and boron trifluoride, and solid acids.

This reaction is carried out at 10 to 250 ° C. for 1 to 30 hours. In the reaction, alcohols such as methanol, ethanol, propanol, butanol, ethylene glycol, methyl cellosolve, ethyl cellosolve, diethylene glycol dimethyl ether, triglyme, and aromatic compounds such as benzene, toluene, chlorobenzene and dichlorobenzene are used as solvents. Can be used. After completion of the reaction, the solvent or water and alcohol produced by the condensation reaction are removed as necessary.

A method for producing the biphenyl aralkyl type epoxy resin represented by the general formula (1) by the reaction of the biphenyl aralkyl type hydroxy resin and epichlorohydrin will be described. This reaction can be performed in the same manner as a well-known epoxidation reaction.

For example, after a biphenylaralkyl type hydroxy resin is dissolved in an excess of epichlorohydrin, in the presence of an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide, the temperature ranges from 50 to 150 ° C., preferably from 60 to 120 ° C. The method of making it react for 10 hours is mentioned. In this case, the amount of epichlorohydrin used is in the range of 0.8 to 2.0 mol, preferably 0.9 to 1.2 mol, relative to 1 mol of hydroxyl group in the polyvalent hydroxy resin. Excess epichlorohydrin was distilled off after completion of the reaction, the residue was dissolved in a solvent such as toluene and methyl isobutyl ketone, filtered, washed with water to remove inorganic salts, and then the solvent was distilled off to remove the general formula ( The target epoxy resin represented by 1) can be obtained. When performing the epoxidation reaction, a catalyst such as a quaternary ammonium salt may be used.

The purity of the biphenyl aralkyl type epoxy resin, in particular the amount of hydrolyzable chlorine, is better from the viewpoint of improving the reliability of the applied electronic component. Although it does not specifically limit, Preferably it is 1000 ppm or less, More preferably, it is 500 ppm or less. In addition, the hydrolyzable chlorine as used in the field of this invention means the value measured by the following method. Specifically, 0.5 g of a sample was dissolved in 30 ml of dioxane, 10 ml of 1N KOH was added, boiled and refluxed for 30 minutes, cooled to room temperature, 100 ml of 80% acetone water was further added, and a potential difference was added with 0.002 N-AgNO ₃ aqueous solution. This is a value obtained by titration.

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

Component (B) is a non-silicone-based modifier selected from non-aromatic epoxy resins or non-silicone rubbers, and this modifier is heated at a rate of temperature increase of 10 ° C./min under a nitrogen stream. The 5% weight loss temperature obtained from the TG / DTA measurement is 260 ° C or higher. And this modifier acts as a modifier for improving tracking resistance.

When the modifier is blended, it is considered that the modifier is phase-separated in the resin, thereby suppressing the aggregation of the carbonized layer that occurs during the thermal decomposition, and an improvement in tracking resistance can be expected.

By using a modifier having a 5% weight loss temperature of 260 ° C. or higher, deterioration of mechanical strength can be prevented even when used at a high temperature of 200 ° C. or higher.

The use of a non-silicone modifier as the modifier has the following advantages. Silicone-based modifiers such as silicone rubber have the potential to cause contact failure when low-molecular components volatilize, and it is difficult to obtain a uniform composition that is easily phase-separated from the epoxy resin. However, such a problem is solved. Further, the non-silicone system is more advantageous in terms of cost.

The content of the modifier is 1 to 50% by weight, preferably 2 to 30% by weight, based on the total of the components (A) to (D).
From another viewpoint, the range of 1 to 50 parts by weight is preferable with respect to 100 parts by weight of the total amount of the resin components in the epoxy resin composition, but preferably 2 to 30 parts by weight. If it is smaller than this, the effect of suppressing the aggregation of the carbonized layer is low. Conversely, if it is larger than this, the glass transition temperature Tg of the cured product is lowered and the mechanical strength is also lowered.

It is preferable that the modifier is dispersed in a phase separated state of 10 μm or less or in the form of particles. The particle diameter (median average diameter) is preferably 0.01 μm to 10 μm, more preferably 0.05 μm to 5 μm, and particularly preferably 0.1 μm to 1 μm.

These modifiers may be well known in the art and are not particularly limited. The modifier having excellent thermal stability is at least one selected from glycidyl esters of divalent aliphatic carboxylic acids having 15 to 64 carbon atoms or glycidyl ethers of divalent aliphatic alcohols having 15 to 64 carbon atoms. A bifunctional epoxy resin containing an epoxy resin as an essential component is preferred.
Rubbers made of styrene rubber or acrylic rubber are also excellent as modifiers.

Examples of the divalent aliphatic carboxylic acid having 15 to 64 carbon atoms include 2-dodecyl succinic acid, hexadecanedioic acid, 8-hexadecenedioic acid, 8,9-diethylhexadecanedioic acid, eicosanedioic acid, and 7-vinyl. Aliphatic dicarboxylic acids such as tetradecanedioic acid, 1,16- (6-ethylhexadecane) dicarboxylic acid, 1,18- (7,12-octadecadiene) dicarboxylic acid, 1,12- (diethyldodecane) dicarboxylic acid, Dimer acid whose main component is a dibasic acid having 36 carbon atoms obtained by an intermolecular reaction of unsaturated fatty acids (linoleic acid, oleic acid, etc.) or water obtained by hydrogenating the dimer acid. Examples thereof include, but are not particularly limited to, dimer acid. Epoxy resins of glycidyl esters of divalent aliphatic carboxylic acids having 15 to 64 carbon atoms can be obtained by diglycidyl esterifying these divalent aliphatic carboxylic acids using a known epoxidation technique.

Examples of the divalent aliphatic alcohol having 15 to 64 carbon atoms include long chain aliphatics such as 1,15-pentadecanediol, 1,16-hexadecanediol, 1,18-octadecanediol, and 1,19-nonadecanediol. Polyethylene glycol such as diol, octaethylene glycol and nonaethylene glycol, polypropylene glycol such as pentapropylene glycol and hexapropylene glycol, and cyclo rings such as 4,4 ′-(propane-2,2-diyl) bis (cyclohexanol) Examples of the diol include dimer diol and hydrogenated dimer diol obtained by reducing the carboxyl group of the dimer acid or hydrogenated dimer acid to a hydroxyl group, but are not particularly limited. Epoxy resins of glycidyl ethers of divalent aliphatic alcohols having 15 to 64 carbon atoms can be obtained by diglycidyl etherifying these divalent aliphatic alcohols using a known epoxidation technique.

As styrene rubber and acrylic rubber, styrene (including substituted styrene), acrylics (acrylic acid, methacrylic acid, acrylic ester, methacrylic ester, rubber component (monomer) or part of raw material, Those containing acrylonitrile and the like) can be used. Non-silicone natural rubber and diene rubber such as butadiene rubber can also be used.

Examples of the styrene rubber include acrylonitrile butadiene styrene copolymer (ABS), acrylonitrile chlorinated polyethylene styrene copolymer (ACS), acrylonitrile ethylene propylene rubber styrene copolymer (AES), and acrylonitrile styrene acrylate copolymer (ASA). ), Methyl methacrylate acrylonitrile butadiene styrene copolymer (MABS), methyl methacrylate butadiene styrene copolymer (MBS), styrene butadiene copolymer (SB), acrylonitrile styrene copolymer (SAN), styrene butadiene styrene block copolymer (SBS), styrene ethylene butylene styrene block copolymer (SEBS), styrene ethylene propylene styrene block copolymer (SEPS), Chi Ren isoprene styrene block copolymer (SIS), acrylonitrile-styrene dimethylsiloxane alkyl acrylate copolymer and the like. Among these, from the viewpoint of reducing elastic modulus and improving impact resistance, styrene butadiene copolymer (SB), methyl methacrylate butadiene styrene copolymer (MBS), acrylonitrile styrene dimethylsiloxane alkyl acrylate copolymer, etc. A rubber obtained by copolymerization with a monomer having a saturated double bond is preferred.

Preferred examples of the acrylic rubber include those obtained by copolymerizing one or more alkyl (meth) acrylates and one or more vinyl monomers copolymerizable therewith, and alkyl (meth) acrylates. As a vinyl monomer copolymerizable with, for example, a crosslinkable monomer is preferable, and aromatic polyfunctional vinyl monomers such as divinylbenzene and divinyltoluene; ethylene glycol di (meth) acrylate, propylene glycol di Di- or tri (meth) acrylates of polyhydric alcohols such as (meth) acrylate, 1,3-butanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate; allyl (meth) acrylate, Diallyl phthalate, diallyl sebacate, triallyl triazine, triallyl cyanurate , Can be mentioned di- or triallyl compounds such as triallyl isocyanurate, may be used those alone, it may be used in combination of two or more.

Component (C) is a curing agent for epoxy resin. As the curing agent, a known curing agent for epoxy resins can be used, but in a field where high electrical insulation properties such as a semiconductor sealing material are required, polyhydric phenols are preferably used as the curing agent. . Below, the specific example of a hardening | curing agent is shown.

Examples of the polyhydric phenols include divalent phenols such as bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, hydroquinone, resorcin, catechol, biphenols, naphthalenediols, and tris- (4-hydroxyphenyl). ) Trivalent or higher typified by methane, 1,1,2,2-tetrakis (4-hydroxyphenyl) ethane, phenol novolak, o-cresol novolak, naphthol novolak, dicyclopentadiene type phenol resin, phenol aralkyl resin, etc. Phenols, further phenols, naphthols, or bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, 4,4 '-biphenol, 2,2' -biphenol, hydride Divalent phenols such as quinone, resorcin, catechol, naphthalene diol and the like, formaldehyde, acetaldehyde, benzaldehyde, p-hydroxybenzaldehyde, p-xylylene glycol, p-xylylene glycol dimethyl ether, divinylbenzene, diisopropenylbenzene, dimethoxy Polyphenolic compounds synthesized by reaction with crosslinkers such as methyl biphenyls, divinyl biphenyls, diisopropenyl biphenyls, biphenyl aralkyl type phenol resins obtained from phenols and bischloromethyl biphenyls, naphthols and para Examples thereof include naphthol aralkyl resins synthesized from xylylene dichloride and the like.

Among these, as a preferable phenol-based curing agent, there is an aralkyl type phenol resin represented by the general formula (2).
In the general formula (2), R is a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. m represents a number of 0 or 1.

By using the above aralkyl-type phenolic resin or a curing agent containing the same, a high Tg property of 200 ° C. or higher required for a power device sealing material is found, and long-term heat stability is maintained by maintaining a glass state during a long-term heat test. Sex is expressed.

The aralkyl type phenol resin represented by the general formula (2) can be produced by reacting salicylaldehyde or p-hydroxyaldehyde with a phenolic hydroxyl group-containing compound.

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

Moreover, in this epoxy resin composition, you may mix | blend another kind of hardening | curing agent other than an aromatic hydroxy compound as a hardening | curing agent component. Examples of the curing agent in this case include dicyandiamide, acid anhydrides, aromatic and aliphatic amines. In the epoxy resin composition of the present invention, one or more of these curing agents can be mixed and used.

Examples of the acid anhydride curing agent include phthalic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, methyl hymic anhydride, dodecynyl succinic anhydride, nadic anhydride, There are trimellitic anhydride and the like.

Examples of amines include aromatic amines such as 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylpropane, 4,4′-diaminodiphenylsulfone, m-phenylenediamine, and p-xylylenediamine, ethylenediamine, There are aliphatic amines such as hexamethylenediamine, diethylenetriamine, and triethylenetetramine.

Component (D) is a curing accelerator for the epoxy resin composition. The curing accelerator may be known in the technical field of epoxy resins and is not particularly limited. Examples include amines, imidazoles, organic phosphines, Lewis acids and the like.
Specifically, tertiary amines such as 1,8-diazabicyclo (5,4,0) undecene-7, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris (dimethylaminomethyl) phenol, -Imidazoles such as methylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, 2-phenyl-4-methylimidazole, 2-heptadecylimidazole, tributylphosphine, methyldiphenylphosphine, triphenylphosphine, Organic phosphines such as diphenylphosphine and phenylphosphine, tetraphenylphosphonium / tetraphenylborate, tetraphenylphosphonium / ethyltriphenylborate, tetrabutylphosphonium / teto Tetra-substituted phosphonium tetra-substituted borate such as borate, 2-ethyl-4-methylimidazole · tetraphenyl borate, and the like tetraphenyl boron salts such as N- methylmorpholine tetraphenylborate. The addition amount is usually in the range of 0.2 to 5 parts by weight with respect to 100 parts by weight of the epoxy resin.

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

In addition, the epoxy resin composition of the present invention can contain additives such as inorganic fillers, pigments, retardants, thixotropic agents, coupling agents, fluidity improvers and the like. Examples of the inorganic filler include silica powder such as spherical or crushed fused silica and crystalline silica, alumina powder, glass powder, mica, talc, calcium carbonate, alumina, hydrated alumina, and the like. A preferable blending amount when used for a stopper is 70% by weight or more, and more preferably 80% by weight or more.

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

Further, if necessary, the resin composition of the present invention includes a release agent such as carnauba wax and OP wax, a coupling agent such as γ-glycidoxypropyltrimethoxysilane, a colorant such as carbon black, and trioxide. Flame retardants such as antimony and lubricants such as calcium stearate can be used.

The epoxy resin composition of the present invention is a solvent after impregnating a fibrous material such as a glass cloth, an aramid nonwoven fabric, a polyester nonwoven fabric such as a liquid crystal polymer, etc. after making it partially or completely dissolved in an organic solvent. It can be removed to form a prepreg. When a solvent-insoluble component such as an inorganic filler is included, it is not necessary to dissolve it, but it is desirable to make it a suspended state to obtain a uniform solution. Moreover, it can be set as a laminated body by apply | coating on sheet-like materials, such as copper foil, stainless steel foil, a polyimide film, and a polyester film depending on the case.

If the epoxy resin composition of the present invention is cured by heating, an epoxy resin cured product can be obtained, and this cured product is excellent in terms of low hygroscopicity, high heat resistance, adhesion, flame retardancy, and the like. Become. The cured product can be obtained by molding the epoxy resin composition by a method such as casting, compression molding or transfer molding. The temperature at this time is usually in the range of 120 to 220 ° C. The epoxy resin composition of the present invention is particularly excellent for a sealing material. Moreover, the semiconductor device of this invention is obtained by sealing a semiconductor element with this epoxy resin composition.

The present invention will be specifically described with reference to synthesis examples, examples and comparative examples. However, the present invention is not limited to these. Unless otherwise specified, “parts” represents parts by weight, and “%” represents% by weight. Moreover, the measuring method was measured with the following method, respectively.

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

2) Melting | fusing point DSC peak temperature was calculated | required on the conditions of the temperature increase rate of 5 degree-C / min with the differential scanning calorimetry apparatus (SII nanotechnology company EXSTAR6000 DSC / 6200). That is, this DSC peak temperature was taken as the melting point of the epoxy resin.

3) Melt viscosity The viscosity was measured at 150 ° C. using a CAP2000H rotational viscometer manufactured by BROOKFIELD.

4) Total chlorine 1.0 g of sample was dissolved in 25 ml of butyl carbitol, 25 ml of 1N-KOH propylene glycol solution was added and heated to reflux for 10 minutes, then cooled to room temperature, and further 100 ml of 80% acetone water was added, and 0.002N -Measured by potentiometric titration with AgNO ₃ aqueous solution.

5) GPC measurement A column (Tosoh Corporation, TSKgel G4000HXL, TSKgel G3000HXL, TSKgel G2000HXL) was used in series with the main body (Tosoh Corporation, HLC-8220GPC), and the column temperature was 40 ° C. Tetrahydrofuran (THF) was used as the eluent, the flow rate was 1 mL / min, and a differential refractive index detector was used as the detector. As a measurement sample, 50 μL of 0.1 g of sample dissolved in 10 mL of THF and filtered through a microfilter was used. For data processing, GPC-8020 Model II version 6.00 manufactured by Tosoh Corporation was used.

6) Glass transition point (Tg)
Tg was determined under the condition of a temperature increase rate of 10 ° C./min using a thermomechanical measuring device (EXSTAR 6000TMA / 6100 manufactured by SII Nano Technology).

7) 5% weight loss temperature (Td5), residual charcoal rate Thermogravimetric / differential thermal analyzer (EXSTAR 6000TG / DTA6200, manufactured by SII NanoTechnology Co., Ltd.) 5% weight loss temperature (Td5) was measured.
Moreover, the weight reduction | decrease in 700 degreeC was measured on the said conditions, and it computed as a residual carbon rate of the resin component in 700 degreeC by converting into the resin component except an inorganic filler.

8) PTI value (600V)
In accordance with IEC60112, a cured resin (20 × 20 × 3 mm) was used as a test piece. The electrode was platinum with a tip angle of 30 degrees, and the electrode arrangement was 4.0 mm and the facing angle was 60 degrees. The electrolyte used was a 0.1% ammonium chloride solution. After adjusting the condition of the test piece for 8 hours at 23 ° C. and 50% RH, a voltage of 600 V was applied in an environment of 23 ° C. and 50% RH, and the electrolyte was dropped, and the test surface caused tracking failure. The number of drops was determined. Moreover, the test was implemented 5 times and the number which does not produce tracking destruction even if it exceeded 50 drops at 600V was measured. As a measuring device, HAT-112-3 manufactured by Yamayo Tester Co., Ltd. was used.

Synthesis example 1
In a 1000 ml four-necked flask, 75.0 g of 4,4′-dihydroxybiphenyl, 115.5 g of diethylene glycol dimethyl ether and 40.5 g of 4,4′-bischloromethylbiphenyl were charged, and the temperature was raised to 170 ° C. with stirring in a nitrogen stream. The reaction was allowed to warm for 20 hours. After the reaction, 46.4 g of diethylene glycol dimethyl ether was recovered. To this reaction mixture, 446.5 g of epichlorohydrin was added, and 69.4 g of a 48% aqueous sodium hydroxide solution was added dropwise over 4 hours at 62 ° C. under reduced pressure (about 130 Torr). During this time, the generated water was removed from the system by azeotropy with epichlorohydrin, and the distilled epichlorohydrin was returned to the system. After completion of the dropwise addition, the reaction was continued for another hour. Thereafter, epichlorohydrin was distilled off, methyl isobutyl ketone was added, the salt was removed by washing with water, filtration and washing were performed, and then methyl isobutyl ketone was distilled off under reduced pressure to obtain 141 g of epoxy resin (epoxy resin 1). . The epoxy equivalent of this epoxy resin was 198. Moreover, the peak temperature in the DSC measurement result of this epoxy resin was 126 ° C., and the melt viscosity at 150 ° C. was 0.25 Pa · s.

Synthesis example 2
A 1 L 4-necked flask was charged with 500 g of phenol (8.0 moles relative to dicyclopentadiene) and 9.5 g of boron trifluoride ether complex as an acid catalyst, and the temperature was raised to 120 ° C. Next, while stirring at 120 ° C., 88 g of dicyclopentadiene was added dropwise over 6 hours to react, and after aging at 130 ° C. for 4 hours, neutralization was performed and phenol was recovered. Subsequently, the product was dissolved in 300 g of MIBK, washed with water 4 times at 80 ° C., and MIBK was distilled off under reduced pressure to obtain 179 g of a polyvalent hydroxy compound. Its hydroxyl equivalent is 178 g / eq. The softening point was 93 ° C. and the weight average molecular weight was 422.

Synthesis example 3
In a four-neck separable flask, 150 g of the resin obtained in Synthesis Example 2, 398 g of epichlorohydrin, and 59 g of diethylene glycol dimethyl ether were added and dissolved by stirring. After uniform dissolution, the mixture was kept at 65 ° C. under a reduced pressure of 130 mmHg, and 68.2 g of 48% aqueous sodium hydroxide solution was added dropwise over 4 hours, and water and epichlorohydrin refluxed during the addition were separated in a separation tank, and epichlorohydrin was The mixture was returned to the reaction vessel, and water was removed from the system to react. After completion of the reaction, the salt produced by filtration was removed, and after further washing with water, epichlorohydrin was distilled off to obtain 157 g of epoxy resin (epoxy resin 2). The epoxy equivalent of the obtained resin was 243 g / eq. The softening point was 84 ° C.

Synthesis example 4
In a 2000 ml four-necked flask, dimer diol (Pripol 20 manufactured by CRODA) was added.
33, hydroxyl group equivalent 270 g / eq. ) 300.0 g, epichlorohydrin 308.3 g, toluene 120.0 g, and water 6.2 g were charged, and the mixture was heated to 50 ° C. with stirring in a nitrogen stream and dissolved. After dissolution, 6.0 g of benzyltrimethylammonium chloride was added, and 13.6 g of 95.5% solid potassium hydroxide was divided and added over 2 hours. After a further 2.5 hours of reaction, 300 g of toluene and 387.5 g of water were added, the salt produced by the liquid separation was removed, epichlorohydrin, toluene and water were distilled off, and 543.2 g of toluene was added and dissolved at 80 ° C. . Thereafter, 12.3 g of a 48.8% potassium hydroxide aqueous solution was added to carry out a purification reaction. After neutralization, washing with water and filtration, toluene was distilled off to obtain 325.9 g of modifier a which is a liquid epoxy resin. . The epoxy equivalent of modifier a is 360 g / eq. The viscosity at 25 ° C. was 243 Pa · s. Moreover, Td5 was 324 degreeC.

The abbreviations used in the examples are as follows.
(Epoxy resin)
Epoxy resin 1; epoxy resin obtained in Synthesis Example 1 epoxy resin 2; o-cresol novolac type epoxy resin (epoxy equivalent 200, softening point 65 ° C., manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.)
Epoxy resin 3; epoxy resin obtained in Synthesis Example 3 (modifier)
Modifier a: Modifier obtained in Synthesis Example 4 Modifier b: ABA-structured radically controlled acrylic block copolymer (NANOSTRENGTH M51, polybutyl acrylate as a soft component and polymethylene methacrylate as a hard component, Arkema Co., Ltd., Td5; 291 ° C)
Modifier c: Indene oligomer (IP-100; manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., softening point 101 ° C., 150 ° C., melt viscosity 1.3 Pa · s, Td 5; 243 ° C.)
(Curing agent)
Curing agent 1: Triphenolmethane type polyvalent hydroxy resin (TPM-100, manufactured by Gunei Chemical Industry Co., Ltd., OH equivalent 97.5, softening point 105 ° C.)
Curing agent 2; phenol novolac type polyvalent hydroxy resin (BRG-557, manufactured by Gunei Chemical Industry Co., Ltd., OH equivalent 105, softening point 80 ° C.)
(Curing accelerator)
2-Phenyl-4,5-dihydroxymethylimidazole (2PHZ-PW, manufactured by Shikoku Chemicals)
(Other)
Silica filler; spherical silica (FB-8S, manufactured by Denki Kagaku Kogyo Co., Ltd.)
Carnauba wax; (TOWAX171, manufactured by Toa Kasei Co., Ltd.)
Carbon black; (MA-100, manufactured by Mitsubishi Chemical Corporation)

Example 1
As the epoxy resin component, epoxy resin 1 obtained in Synthesis Example 1; 64.0 g, modifier a; 5.1 g, and curing agent 1 32.9 g were used. Further, 1.0 g of a curing accelerator was used, and 498 g of silica filler was used as an inorganic filler. Furthermore, 0.5 g of carnauba wax as a release agent and 0.5 g of carbon black as a colorant were added, and these were kneaded to obtain an epoxy resin composition. Using this epoxy resin composition, a molding temperature of 175 ° C. for 3 minutes. A cured product test piece was obtained at a post-cure temperature of 200 ° C. for 5 hours.

Examples 2-5, Comparative Examples 1-5
Similarly to Example 1, an epoxy resin, a modifier, a curing agent, an inorganic filler, a curing accelerator, and other additives were kneaded at a blending ratio shown in Table 1 to prepare an epoxy resin composition. And molding temperature 175 ° C., 3 minutes. A cured product test piece was obtained at a post-cure temperature of 200 ° C. for 5 hours. In addition, the numerical value in a table | surface shows the weight part in a mixing | blending.

As is clear from these results, it was found that the epoxy resin compositions obtained in the examples had both heat resistance having a glass transition temperature (Tg) of 200 ° C. or higher and high tracking resistance.

According to the present invention, an epoxy resin cured product having excellent tracking resistance, a balance with heat resistance and excellent thermal decomposition stability can be obtained, and it is suitable as a semiconductor sealing material, particularly as an automotive power semiconductor sealing material. is there.

Claims

The following components (A) to (D);
(A) an aromatic epoxy resin represented by the following general formula (1),
(B) A modification selected from a non-aromatic epoxy resin or a non-silicone rubber having a 5% weight reduction temperature of 260 ° C. or higher obtained from a TG / DTA measurement at a heating rate of 10 ° C./min under a nitrogen stream. Texture agent,
An epoxy resin composition containing (C) a curing agent and (D) a curing accelerator as essential components, and containing 1 to 50% by weight of component (B) with respect to the total of components (A) to (D) An epoxy resin composition characterized by comprising:

Here, n represents a number from 0 to 20, and G represents a glycidyl group.
The component (B) contains at least one epoxy resin selected from glycidyl esters of divalent aliphatic carboxylic acids having 15 to 64 carbon atoms or glycidyl ethers of divalent aliphatic alcohols having 15 to 64 carbon atoms. The epoxy resin composition according to claim 1, which is a modifier composed of a bifunctional epoxy resin.
The epoxy resin composition according to claim 1, wherein the component (B) is a rubber-based modifier made of styrene rubber or acrylic rubber.
The epoxy resin composition according to claim 2 or 3, wherein the component (C) is a curing agent containing a phenol resin represented by the following general formula (2).

R represents a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, and m represents a number of 0 or 1.
An epoxy resin cured product obtained by curing the epoxy resin composition according to any one of claims 1 to 4.
A semiconductor device in which a semiconductor element is sealed with the epoxy resin composition according to any one of claims 1 to 4.