JP2001114863A - Epoxy resin composition and its cured material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an epoxy resin composition capable of giving its cured product excellent in molding property, heat resistance, low moisture-absorbing property, solder reflow property, flame resistance, etc., suitable for an electronic part-sealing use. SOLUTION: This epoxy resin composition is obtained by using an aralkyl type epoxy resin A expressed by general formula 1 as the epoxy resin, and an aralkyl type polyhydric hydroxy resin B expressed by general formula 2, having 100-150 deg.C softening point and 1-20 Pa.s melt viscosity [in the formulae, A is benzene ring, naphthalene ring or biphenyl ring allowed to be substituted; B is naphthalene ring; R1 to R4 are each H or a 1-6C hydrocarbon; G is glycidyl group; (l), (n) are each 1 or 2 integer; and (n), (p) are each 1-15].

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy resin composition having excellent curability, heat resistance, low hygroscopicity, solder reflowability and the like, and which gives a cured product having particularly excellent flame retardancy, and a cured epoxy resin composition. And a cured product obtained by the above method.

[0002]

2. Description of the Related Art A resin composition containing an epoxy resin as a main component is widely used in electric and electronic fields such as casting, sealing, and laminates. In particular, in the field of semiconductors, since the transition from the conventional pin insertion method to the surface mounting method is progressing as a method of mounting components on a printed circuit board, electronic component encapsulation having particularly excellent solder reflow properties. Materials and printed circuit board materials are desired. That is, in the surface mounting method, since the entire package and the entire printed board are heated to the solder temperature, package cracks due to thermal shock and poor reliability of the printed board are becoming serious problems. Furthermore, in recent years, high integration of semiconductor devices, increase in device size, and miniaturization of wiring width are also rapidly progressing.
These problems are becoming more serious.

[0003] In addition, from the viewpoint of ensuring safety against fire, epoxy resin compositions used in the electric and electronic fields have flame retardant standards in various countries around the world.
A wide variety of flame retardants are used to satisfy this flame retardant standard. In recent years, from the viewpoints of environment, safety, and improvement in reliability as a material, a flame-retarding method using no halogen-based flame retardant and antimony compound, that is, a flame retardant has been desired.

[0004] For example, in the case of materials for sealing electronic parts, a high filling rate of filler is aimed at from the viewpoint of improving solder reflow properties, and low-viscosity bifunctional epoxy resins are widely studied. Therefore, an epoxy resin composition containing a biphenyl epoxy resin as a main component in Japanese Patent Publication No. 4-73565 and a bisphenol F type solid epoxy resin as a main component in JP-A-6-345850 has been proposed. There is a transition point problem. In recent years, semiconductor packages have become larger and B
With the development of GA packages, etc., the problem of package warpage has been strongly pointed out, and it has excellent solder reflow properties.
An epoxy resin composition having a high glass transition point is desired.

The epoxy resin represented by the general formula (1) according to the present invention as an epoxy resin having a high glass transition point is already known in Japanese Patent Application Laid-Open No. 4-255714, but is usually represented by phenol novolak. There is a drawback that the water absorption increases when cured using a curing agent,
An improvement in solder reflowability cannot be expected. Also, an aralkyl polyhydric hydroxy resin is known as a curing agent,
When combined with ordinary epoxy resins such as bisphenol A type epoxy resin and o-cresol novolak type epoxy resin, a high glass transition point cannot be expected and an improvement in solder reflow properties cannot be expected. Further, an example in which an aralkyl-type polyvalent hydroxy resin as a curing agent is combined with an epoxy resin represented by the general formula (1) according to the present invention is disclosed in JP-A-10-292032, but heat resistance,
It is not always sufficient in terms of compatibility with low moisture absorption, particularly in terms of flame retardancy when a halogen-based flame retardant and an antimony compound are not used.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide moldability such as rapid curability and fluidity, heat resistance, low moisture absorption,
To provide an epoxy resin composition having excellent solder reflow properties and, in particular, providing a cured product having excellent flame retardancy, and is particularly suitable for sealing electronic parts such as surface-mounted semiconductor elements, and for printed circuit boards. An object of the present invention is to provide an epoxy resin composition and a cured product thereof.

[0007]

Means for Solving the Problems The present inventors have made intensive studies in view of the above problems, and as a result, achieved the above object by combining a specific polyfunctional epoxy resin with a specific aralkyl type curing agent. We have found that we have completed the present invention.

That is, the present invention provides an epoxy resin represented by the following general formula (1):

Embedded image (Wherein, A represents a benzene ring, a naphthalene ring or a biphenyl ring which may be substituted with a hydrocarbon group having 1 to 6 carbon atoms, and R ₁ and R ₂ represent a hydrogen atom or a hydrocarbon having 1 to 6 carbon atoms. An aralkyl type epoxy resin (A) represented by the following general formula (A), wherein G is a glycidyl group, l is an integer of 1 or 2, and n is a number of 1 to 15. 2)

Embedded image (Wherein B represents a naphthalene ring which may be substituted with a hydrocarbon group having 1 to 6 carbon atoms, R ₃ and R ₄ represent a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, l and m is 1 or 2
And p represents a number of 1 to 15. And an aralkyl-type polyvalent hydroxy resin (B) having a softening point of 100 to 150 ° C and a melt viscosity at 150 ° C of 1 to 20 Pa · s. It is. Aralkyl epoxy resin (A) 100
Aralkyl-type polyhydroxy resin (B) based on parts by weight
Is preferably contained in an amount of 40 to 150 parts by weight. Further, the aralkyl type epoxy resin (A) preferably accounts for 10 to 100% by weight of the total epoxy resin, and the aralkyl type polyvalent hydroxy resin (B) preferably accounts for 10 to 100% by weight of the total curing agent. Furthermore, the aralkyl type epoxy resin (A) is 80 to 100% by weight of the total epoxy resin,
The aralkyl-type polyhydroxy resin (B) is the total hardener of 8
More preferably, it is 0 to 100% by weight. Further, the present invention is a cured product obtained by curing the epoxy resin composition.

Hereinafter, the present invention will be described in detail. The epoxy resin (A) represented by the above general formula (1), which is an essential component of the epoxy resin composition of the present invention, comprises a polyvalent hydroxy resin represented by the following general formula (a) and epichlorohydrin. Can be produced by reacting
The polyhydroxy resin can be produced by reacting a bifunctional phenolic compound with an aromatic crosslinking agent.

Embedded image (Wherein, A represents a benzene ring, a naphthalene ring or a biphenyl ring which may be substituted with a hydrocarbon group having 1 to 6 carbon atoms. In addition, R ₁ and R ₂ represent a hydrogen atom or a carbon atom having 1 to 6 carbon atoms. Represents a hydrocarbon group, l is an integer of 1 or 2, and n is a number of 1 to 15.)

Examples of the bifunctional phenolic compound used as a raw material for synthesizing a polyhydric hydroxy resin include dihydroxybenzenes such as catechol, resorcin and hydroquinone;
Dihydroxynaphthalenes such as 1,4-naphthalene diol, 1,5-naphthalene diol, 1,6-naphthalene diol, 1,7-naphthalene diol, 2,6-naphthalene diol, and 2,7-naphthalene diol;
Dihydroxybiphenyls such as 4′-dihydroxybiphenyl and 2,2′-dihydroxybiphenyl; These bifunctional phenolic compounds have 1 carbon atom.
To 6 hydrocarbon groups. Examples of the substituent include a methyl group, an ethyl group, an isopropyl group, an allyl group, a tertiary butyl group, an amyl group, a cyclohexyl group, and a phenyl group. In addition, these bifunctional phenolic compounds may be used alone or in combination of two or more. If necessary, monofunctional phenols such as phenol, cresol and xylenol may be used in combination with the bifunctional phenolic compound as long as the object of the present invention is not impaired. In this case, the amount of the monofunctional phenol used is preferably 50% by weight or less based on the whole phenolic compound.

The aromatic crosslinking agent includes, for example, diglycols or dialkoxy compounds represented by the following general formula (b) and dialkenyl compounds represented by the following general formula (c).

Embedded image

Embedded image (In the formula, R ₁ , R ₂ , R ₅ , R ₆ and R ₇ represent a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, and 1 represents an integer of 1 or 2.)

The aromatic crosslinking agent includes those having a benzene skeleton and those having a biphenyl skeleton. The compound having a benzene skeleton may be any of an o-form, an m-form and a p-form, but is preferably an m-form or a p-form. Specifically, p-xylylene glycol, α, α ′
-Dimethoxy-p-xylene, α, α'-diethoxy-
p-xylene, α, α′-diisopropoxy-p-xylene, α, α′-dibutoxy-p-xylene, m-xylylene glycol, α, α′-dimethoxy-m-xylene, α, α′- Diethoxy-m-xylene, α, α'-
Diisopropoxy-m-xylene, α, α′-dibutoxy-m-xylene, 1,4-di (2-hydroxy-2-
Ethyl) benzene, 1,4-di (2-methoxy-2-ethyl) benzene, 1,4-di (2-ethoxy-2-ethyl) benzene, 1,4-di (2-isopropoxy-2-
Ethyl) benzene, 1,4-di (2-hydroxy-2-
Propyl) benzene, 1,4-di (2-methoxy-2-
Propyl) benzene, 1,4-di (2-ethoxy-2-
Propyl) benzene, 1,4-di (2-isopropoxy-2-propyl) benzene, 1,3-di (2-hydroxy-2-ethyl) benzene, 1,3-di (2-methoxy-2-ethyl) ) Benzene, 1,3-di (2-hydroxy-2-propyl) benzene, 1,3-di (2-methoxy-2-propyl) benzene, 1,2-divinylbenzene, 1,3-divinylbenzene, 1,4-divinylbenzene, 1,2-di (2-propenyl) benzene, 1,3
-Di (2-propenyl) benzene, 1,4-di (2-propenyl) benzene and the like.

Further, those having a biphenyl skeleton include 4,4'-dihydroxymethylbiphenyl,
4'-dihydroxymethylbiphenyl, 2,2'-dihydroxymethylbiphenyl, 4,4'-dimethoxymethylbiphenyl, 2,4'-dimethoxymethylbiphenyl, 2,2'-dimethoxymethylbiphenyl, 4,4 '
-Diisopropoxymethylbiphenyl, 2,4'-diisopropoxymethylbiphenyl, 2,2'-diisopropoxymethylbiphenyl, 4,4'-dibutoxymethylbiphenyl, 2,4'-dibutoxymethylbiphenyl,
2,2'-dibutoxymethylbiphenyl, 4,4'-di (2-hydroxy-2-ethyl) biphenyl, 4,4 '
-Di (2-methoxy-2-ethyl) biphenyl, 4,
4′-di (2-ethoxy-2-ethyl) biphenyl,
4,4'-di (2-isopropoxy-2-ethyl) biphenyl, 4,4'-di (2-hydroxy-2-propyl) biphenyl, 4,4'-di (2-methoxy-2-propyl) Biphenyl, 4,4'-di (2-ethoxy-2
-Propyl) biphenyl, 4,4'-di (2-isopropoxy-2-propyl) biphenyl, 2,4'-di (2
-Hydroxy-2-ethyl) biphenyl, 2,4'-di (2-methoxy-2-ethyl) biphenyl, 2,4'-
Di (2-hydroxy-2-propyl) biphenyl, 2,
4′-di (2-methoxy-2-propyl) biphenyl,
2,4'-divinylbiphenyl, 2,2'-divinylbiphenyl, 4,4'-divinylbiphenyl, 2,4'-
Di (2-propenyl) biphenyl, 2,2′-di (2-propenyl) biphenyl, 4,4′-di (2-propenyl) biphenyl and the like. Substitution positions of a functional group such as a methylol group for biphenyl are 4,4′-positions,
2,4′-position or 2,2′-position,
The preferred compound as the aromatic cross-linking agent is the 4,4'-isomer, and particularly preferably the compound containing 50% by weight or more of the 4,4'-isomer in the total cross-linking agent. If the amount is less than this, there are disadvantages such as a decrease in curing speed when curing the epoxy resin and an obtained cured product becomes brittle.

In the reaction between the bifunctional phenolic compound and the aromatic crosslinking agent, an excess amount of the bifunctional phenolic compound relative to the aromatic crosslinking agent is used. The amount of the aromatic cross-linking agent used is 0.1 to 0.1 mol per 1 mol of the bifunctional phenolic compound.
0.9 mole, preferably 0.2 to 0.7 mole. If the amount of the aromatic cross-linking agent is more than 0.9 mol, the softening point of the resin becomes high and the molding workability is hindered. The removal amount increases, which is not industrially preferable.

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

Usually, this reaction is carried out at 10-250 ° C. for 1-2
Perform for 0 hours. Further, as a solvent at the time of the reaction, for example, alcohols such as methanol, ethanol, propanol, butanol, ethylene glycol, methyl cellosolve, ethyl cellosolve, diglyme, triglyme, and aromatic compounds such as benzene, toluene, chlorobenzene, and dichlorobenzene It is better to use such as. When using 4,4′-dihydroxybiphenyl, 1,5-naphthalenediol, and 2,6-naphthalenediol having high crystallinity, the solvent used is ethyl cellosolve, diglyme,
Triglyme is preferred. After the completion of the reaction, the obtained polyvalent hydroxy resin may be removed by a method such as distillation under reduced pressure, washing with water or reprecipitation in a poor solvent, but as a raw material for the epoxidation reaction while leaving the solvent. May be used.

The polyhydric hydroxy resin thus produced is represented by the above general formula (a). Preferably, A is an unsubstituted or methyl-substituted benzene or naphthalene ring. Or a biphenyl ring, and the average number of repetitions n is 1 to 5.

The epoxy resin used in the epoxy resin composition of the present invention can be produced by reacting the above polyhydroxy resin with epichlorohydrin.
This reaction can be performed in the same manner as a usual epoxidation reaction. For example, after dissolving a polyvalent hydroxy resin in an excess of epichlorohydrin, the solution is dissolved in an amount of 50 to 15 in the presence of an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide.
A method in which the reaction is carried out at 0 ° C, preferably 60 to 120 ° C for 1 to 10 hours, may be mentioned. At this time, the amount of the alkali metal hydroxide to be used is 0.8 to 1.2 mol, preferably 0.9 to 1 mol, per 1 mol of the hydroxyl group in the polyhydroxy compound.
0 mol. Further, epichlorohydrin is used in excess with respect to the hydroxyl groups in the polyvalent hydroxy resin.
1.5 to 15 mol, preferably 2 to 8 mol. After completion of the reaction, excess epichlorohydrin is distilled off, the residue is dissolved in a solvent such as toluene or methyl isobutyl ketone, filtered, washed with water to remove inorganic salts, and then the solvent is distilled off to obtain a compound of the general formula The epoxy resin (A) represented by (1) can be obtained. In addition, the general formula (1),
In (2), (a), (b) and (c), when there are two or more identical symbols in the same formula, they may be the same groups or atoms as long as they are defined groups or atoms. , Different groups or atoms.

The purity of the epoxy resin, particularly the amount of hydrolyzable chlorine, is preferably smaller than the viewpoint of improving the reliability of the electronic component to be sealed. Although not particularly limited, 100
0 ppm or less is good. In addition, the hydrolyzable chlorine referred to in the present invention refers to a value measured by the following method. That is, 0.5 g of a sample is dissolved in 30 ml of dioxane,
10 ml of an aqueous solution of N-KOH was added, and the mixture was boiled and refluxed for 30 minutes.
Is added, and potentiometric titration is performed with a 0.002 N-AgNO3 aqueous solution, and this is a value obtained.

The viscosity and softening point of the epoxy resin can be easily adjusted by changing the molar ratio of the bifunctional phenolic compound and the crosslinking agent when synthesizing the polyhydroxy resin as the raw material of the epoxy resin. However, a preferable softening point range is 60 to 150 ° C. Softening point range is 60 ° C
If the temperature is lower than this, the heat resistance of the epoxy resin composition decreases, and if it is higher than 150 ° C., the workability decreases due to an increase in viscosity.

The epoxy resin composition of the present invention may contain, in addition to the above-mentioned epoxy resin (A) which is an essential component, a general epoxy resin having two or more epoxy groups in a molecule. Examples of such an epoxy resin include bisphenol A, bisphenol F, bisphenol S,
Fluorene bisphenol, 4,4'-biphenol,
Divalent phenols such as 2,2'-biphenol, hydroquinone, resorcin, tris- (4-hydroxyphenyl) methane, 1,1,2,2-tetrakis (4-hydroxyphenyl) ethane, phenol novolak, o
-Trivalent or more phenols such as cresol novolak,
Glucidyl ether compounds derived from halogenated bisphenols such as tetrabromobisphenol A are exemplified. These epoxy resins may be used alone or in combination of two or more. However, the mixing ratio of the epoxy resin (A) of the general formula (1) is 10 to 100 in all epoxy resins.
% By weight, preferably 50% by weight or more, more preferably 8% by weight or more.
The content is preferably 0% by weight or more.

Next, the aralkyl polyhydroxy resin (B) represented by the general formula (2) is obtained by reacting a phenolic hydroxyl group-containing compound having an alkyl-substituted or unsubstituted naphthalene ring with an aromatic crosslinking agent. It can be manufactured by doing.

Examples of the phenolic hydroxyl group-containing compound which is a raw material for synthesizing the aralkyl-type polyhydroxy resin include:
For example, 1-naphthol, 2-naphthol, naphthalene diols and the like can be mentioned. The aromatic cross-linking agent is the same as the aromatic cross-linking agent used as a raw material for synthesizing the polyvalent hydroxy resin, that is, the one having a benzene skeleton or a biphenyl skeleton represented by the general formula (b) or (c). Can be used.

The aralkyl-type polyhydroxy resin (B) is represented by the general formula (2)
Is 1 to 15, preferably 1 to 5. The value of p can be easily adjusted by changing the molar ratio of the phenolic hydroxyl group-containing compound and the aromatic crosslinking agent when they are reacted. That is, the more the phenolic hydroxyl group-containing compound is used relative to the aromatic crosslinking agent, the smaller the value of p can be controlled. The larger the value of p, the higher the softening point and viscosity of the obtained resin, and the lower the moldability. Also, p
The smaller the value, the lower the viscosity and the better the moldability, but the more unreacted phenolic hydroxyl group-containing compounds during the synthesis, the lower the production efficiency of the resin. The molar ratio of the two is practically 1 mol or less, preferably 0.1 to 0.9 mol of the aromatic crosslinking agent per 1 mol of the phenolic hydroxyl group-containing compound. If the amount is less than 0.1 mol, the amount of the unreacted phenolic hydroxyl group-containing compound increases, and if it exceeds 0.9 mol, the softening point of the resin increases, which impairs the molding workability.

The softening point of the aralkyl-type polyhydroxy resin (B) is from 100 to 150 ° C., preferably from 110 to 130 ° C. When the softening point is lower than 100 ° C., the heat resistance of the epoxy resin composition is reduced, and the effect of improving the flame retardancy is small. If the temperature is higher than 150 ° C., the workability is lowered due to the increase in viscosity.

The aralkyl polyhydric hydroxy resin (B) has the above softening point range and has a
It is necessary that the melt viscosity at ℃ is 1 to 20 Pa · s. If the melt viscosity is lower than 1 Pa · s, the heat resistance of the epoxy resin composition is reduced, and the effect of improving the flame retardancy is small. If it is higher than 20 Pa · s, the workability is lowered due to the increase in viscosity.

Preferred examples of the aralkyl-type polyhydroxy resin (B) used in the present invention include naphthols,
p-xylylene glycol or α, α'-dimethoxy-
There is a naphthol aralkyl-type resin obtained by condensing with p-xylene. Specific examples include Nippon Steel Chemical Co., Ltd.
SN-4115, SN-3120 and the like.

The epoxy resin composition of the present invention may contain a phenolic hydroxyl group-containing substance known as an epoxy resin curing agent, in addition to the aralkyl-type polyvalent hydroxy resin (B). Examples of such a curing agent include bisphenol A, bisphenol F, bisphenol S,
Fluorene bisphenol, 4,4'-biphenol,
Divalent phenols such as 2,2′-biphenol, hydroquinone, resorcinol, naphthalene diol, and tris- (4-hydroxyphenyl) methane, 1,1,
Trivalent or higher phenols represented by 2,2-tetrakis (4-hydroxyphenyl) ethane, phenol novolak, o-cresol novolak, naphthol novolak, polyvinylphenol, etc., phenols,
Naphthols or bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol,
2, 4'-biphenol, 2,2'-biphenol, hydroquinone, resorcinol, naphthalene diol and the like
And polyhydric hydroxy compounds synthesized with a condensing agent such as a phenol having a valence and formaldehyde, acetaldehyde, benzaldehyde, p-hydroxybenzaldehyde, dicyclopentadiene and the like. These curing agents may be used alone or in combination of two or more. However, the blending ratio of the aralkyl-type polyvalent hydroxy resin (B) of the general formula (2) is 10 to 100% by weight of the total curing agent. It is preferably at least 50% by weight, more preferably at least 80% by weight.

The epoxy resin composition of the present invention contains an epoxy resin and a curing agent. A preferable ratio of the epoxy resin and the curing agent in the composition is an equivalent ratio of 0.8 to 1.2. Preferably it is 0.9-1.1. When the ratio is out of this range, it is difficult to simultaneously achieve the heat resistance, low moisture absorption, solder reflow properties, flame retardancy, fast curing property, and fluidity, which are the objects of the present invention. Also, aralkyl type epoxy resin (A)
The weight ratio (B) / (A) of the aralkyl-type polyvalent hydroxy resin (B) is preferably 0.4 to 1.8, and more preferably 0.4 to 1.50.

Conventionally known curing accelerators can be used in the resin composition of the present invention. Examples include amines, imidazoles, organic phosphines, Lewis acids, and the like. Specifically, 1,8-diazabicyclo (5,4,
0) Tertiary amines such as undecene-7, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris (dimethylaminomethyl) phenol, 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methyl Imidazoles, imidazoles such as 2-heptadecyl imidazole, tributylphosphine, methyldiphenylphosphine, triphenylphosphine, diphenylphosphine,
Organic phosphines such as phenylphosphine, tetraphenylphosphonium / tetraphenylborate, tetraphenylphosphonium / ethyltriphenylborate,
Tetra-substituted phosphonium-tetra-substituted borates such as tetrabutylphosphonium-tetrabutyl borate; tetraphenylboron salts such as 2-ethyl-1-methylimidazole-tetraphenylborate; and N-methylmorpholine-tetraphenylborate. The amount of addition is usually 0.1 to 100 parts by weight of the epoxy resin.
It is in the range of 2 to 10 parts by weight.

In the resin composition of the present invention, an inorganic filler can be used according to the purpose. Examples of the inorganic filler to be used include powders of silica, alumina, zircon, calcium silicate, calcium carbonate, silicon carbide, silicon nitride, boron nitride, zirconia, fosterite, steatite, spinel, mullite, titania, and the like. Spherical beads can be used, and these can be used alone or in combination of two or more.

One of the objects of the present invention is to seal electronic components such as surface-mounted semiconductor elements. In such a case, it is desirable to contain an inorganic filler in a high content. From the viewpoint of increasing the filling of the inorganic filler, spherical fused silica is preferably used. Usually, silica is used in combination with one having several types of particle size distribution. The preferred average particle size of the combined silica ranges from 0.5 to 100 microns, more preferably 10 to 50 microns. 70 wt% of inorganic filler in epoxy resin composition
% Or more, more preferably 80% by weight or more.
If the amount is less than this, the effect of improving low moisture absorption, solder reflowability, and flame retardancy is small.

In addition, thermoplastic oligomers can be added to the resin composition of the present invention from the viewpoint of improving the fluidity during molding and improving the adhesion to lead frames, copper foils and the like. As thermoplastic oligomers, C5 and C9 petroleum resins, styrene resins, indene resins, indene / styrene copolymer resins, indene / styrene / phenol copolymer resins, indene / coumarone copolymer resins,
An indene / benzothiophene copolymer resin is exemplified. The addition amount is usually in the range of 2 to 30 parts by weight based on 100 parts by weight of the epoxy resin. Further, if necessary, the resin composition of the present invention may contain a releasing agent such as carnauba wax or an ester-based wax, an epoxy silane, an amino silane, a ureido silane, a vinyl silane, an alkyl silane, an organic titanate, or a coupling such as aluminum alcoholate. Agents, coloring agents such as carbon black, low stress agents such as silicone oil, lubricants such as higher fatty acids and metal salts of higher fatty acids, and the like.

In general, the above-mentioned raw materials are sufficiently mixed with a predetermined amount of raw materials by a mixer or the like, and then kneaded by a mixing roll, an extruder, or the like, and cooled and pulverized to form a molding material. Can be prepared. As a method for sealing an electronic component using the molding material obtained in the present invention, a low-pressure transfer molding method is the most common, but an injection molding method or a compression molding method is also possible.

[0035]

The present invention will be described more specifically with reference to the following examples. Reference Examples 1 and 2 are synthesis examples of epoxy resin (A), Reference Examples 3 and 4 are synthesis examples of aralkyl-type polyvalent hydroxy resin (B) as a curing agent, and Reference Example 5 is the present invention. This is an example of synthesizing an aralkyl-type polyvalent hydroxy resin not applicable to the polyvalent hydroxy resin (B).

Reference Example 1 In a 500 ml four-necked flask, 186 g (1.0 mol) of 4,4'-dihydroxybiphenyl, 41.4 g (0.3 mol) of p-xylylene glycol, 60 ml of diglyme were added.
And 2.5 g of p-toluenesulfonic acid, and reacted at 160 ° C. for 4 hours while stirring under a nitrogen stream. Water generated during this time was removed from the system. After the reaction, the reaction solution was transferred to a four-necked flask, cooled to 100 ° C. or lower, and 830 g of epichlorohydrin was added. Then, under reduced pressure (about 140m
mHg) 48% sodium hydroxide aqueous solution 163 at 65 ° C.
g was added dropwise over 4 hours. During this time, water was removed from the system by azeotropic distillation with epichlorohydrin, and the distilled out epichlorohydrin was returned to the system. After the completion of the dropwise addition, the reaction was continued for another 30 minutes. Thereafter, diglyme remaining in the system and excess epichlorohydrin were distilled off under reduced pressure, dissolved in 1500 ml of methyl isobutyl ketone, and the generated salt was removed by filtration. Thereafter, 15 g of a 10% aqueous sodium hydroxide solution was added, and the mixture was reacted at 80 ° C. for 2 hours. After further washing with water and neutralization, methyl isobutyl ketone was distilled off to obtain 274 g of an epoxy resin. The epoxy equivalent was 173 and the melting point was 110 to 142 ° C. In addition, hydrolyzable chlorine was 310 ppm.

Reference Example 2 A 500 ml four-necked flask was charged with 160 g (1.0 mol) of 1,6-naphthalenediol, 69.0 g (0.5 mol) of p-xylylene glycol, and 1.6 g of oxalic acid. The reaction was carried out at 150 ° C. for 4 hours while stirring under a nitrogen stream. Water generated during this period is excluded from the system, and the OH equivalent is 1
203 g of 10 brown resins were obtained. 100 g of this resin was transferred to a four-necked flask, dissolved in 400 g of epichlorohydrin, and 73 g of a 48% aqueous sodium hydroxide solution was added dropwise at 65 ° C. under reduced pressure (about 140 mmHg) over 4 hours. During this time, water was removed from the system by azeotropic distillation with epichlorohydrin, and the distilled epichlorohydrin was returned to the system. After the completion of the dropwise addition, the reaction was continued for another 30 minutes. Thereafter, excess epichlorohydrin remaining in the system was distilled off under reduced pressure, dissolved in 700 ml of methyl isobutyl ketone, and the generated salt was removed by filtration. Thereafter, 7.5 g of a 10% aqueous sodium hydroxide solution was added, and the mixture was reacted at 80 ° C. for 2 hours.
After further washing with water and neutralization, methyl isobutyl ketone was distilled off to obtain 129 g of an epoxy resin. The epoxy resin had an epoxy equivalent of 171 and a softening point of 78 ° C. The content of hydrolyzable chlorine was 490 ppm.

Reference Example 3 288 g (2.0 mol) of 1-naphthol and p-xylylene glycol dimethyl ether 16 were placed in a four-necked flask.
6 g (1.0 mol) and 0.23 g of 48% sulfuric acid were charged and reacted at 180 ° C. for 2 hours while stirring under a nitrogen stream. Methanol generated during this time was removed from the system. Thereafter, sulfuric acid was removed by washing with water. Further, unreacted 1-naphthol is removed by steam distillation, and the brown resin 304 is removed.
g was obtained. The OH equivalent of the obtained resin was 235, the softening point was 115 ° C., and the melt viscosity at 150 ° C. was 4 Pa · s.

REFERENCE EXAMPLE 4 160 g of 1,6-naphthalene diol was placed in a four-necked flask.
(1.0 mol), 83 g (0.5 mol) of p-xylylene glycol dimethyl ether and 0.73 g of 50% p-toluenesulfonic acid were reacted at 150 ° C. for 3 hours while stirring under a nitrogen stream. Methanol generated during this time was removed from the system. Then, after dissolving in methyl isobutyl ketone, it was washed with water to remove p-toluenesulfonic acid. Further, methyl isobutyl ketone was removed by distillation under reduced pressure to obtain 194 g of a brown resin. The OH equivalent of the obtained resin was 112, the softening point was 121 ° C., and the melt viscosity at 150 ° C. was 6.5 Pa · s.

Reference Example 5 In a four-necked flask, 288 g (2.0 mol) of 1-naphthol and p-xylylene glycol dimethyl ether 11 were added.
6.2 g (0.7 mol) and 0.20 g of 48% sulfuric acid were charged and reacted at 180 ° C. for 2 hours while stirring under a nitrogen stream. Methanol generated during this time was removed from the system.
Thereafter, sulfuric acid was removed by washing with water. Further, unreacted 1-naphthol is removed by steam distillation, and the brown resin 24
0 g was obtained. The obtained resin has an OH equivalent of 208, a softening point of 87 ° C., and a melt viscosity at 150 ° C. of 0.2 Pa ·
s.

Examples 1 to 5 and Comparative Examples 1 to 5 In order to evaluate the properties as an epoxy resin composition for use in electronic parts and the like, the following evaluations were made by formulating and evaluating an electronic part sealing material. Was done. As the epoxy resin component, the epoxy resins of Reference Examples 1 and 2 and an o-cresol novolak type epoxy resin (ECN: Nippon Kayaku, EOCN
-1020-80; epoxy equivalent 200, hydrolyzable chlorine 400 ppm,
Softening point 80 ° C), and as a curing agent, Reference Examples 3, 4,
No. 5 naphthol aralkyl type polyhydroxy resin and phenol aralkyl type polyhydroxy resin (PA: manufactured by Mitsui Chemicals, Millex XL-225-L; OH equivalent 180, softening point 85)
℃, 150 ℃ melt viscosity 1Pa ・ s) phenol novolak (P
N: manufactured by Gunei Chemical Co., PSM-4324; OH equivalent: 103, softening point: 100
° C, 150 ° C melt viscosity 0.9 Pa · s) was used. Furthermore, spherical silica (average particle size: 18 μm) as a filler, triphenylphosphine as a curing accelerator, carbon black as a coloring agent, and carnauba wax as a release agent were kneaded in the composition shown in Table 1 and mixed with an epoxy resin. A composition was obtained. This epoxy resin composition was molded at 175 ° C.
After post-curing at 12 ° C. for 12 hours to obtain a cured product test piece, it was subjected to various physical property measurements. Table 2 shows the results. The various physical property measurements in Table 2 are based on the following evaluation methods.

(Hot hardness) The hot hardness is 90 at 175 ° C.
The test piece that had been subjected to second molding was measured by a Barcol hardness tester. (Glass transition point) The glass transition point was determined by a thermomechanical measuring apparatus at a temperature rising rate of 10 ° C./min. (Water absorption) The water absorption was measured using the epoxy resin composition of 5%.
Form a disc of 0mmΦ × 3mm, post cure and 85 ℃,
This is the case when moisture is absorbed for 100 hours under the condition of 85% RH. (Flame Retardancy) Flame retardancy was evaluated by molding a test piece having a thickness of 1/16 inch according to UL94V-0 standard. Quantitatively, the total framing time in the test of n = 5 was shown as an index. (Crack occurrence rate) The crack occurrence rate was QFP-80p
In (14 × 20 × 2.5 mm), after post-curing, after absorbing moisture for 85 hours at 85 ° C. and 85% RH under the same conditions as water absorption, immersed in a 260 ° C. solder bath for 10 seconds And the state of the package was observed and determined.

[0043]

[Table 1]

[0044]

[Table 2]

Examples 1 to 3 satisfying the conditions specified in the present invention
It can be seen that all Nos. 5 are excellent in moldability such as rapid curability and fluidity, and give cured products excellent in heat resistance, low hygroscopicity, solder reflowability, flame retardancy and the like. On the other hand, Comparative Examples 1 to 5, which do not satisfy the conditions specified in the present invention, are not simultaneously superior in these properties to Examples.

[0046]

The epoxy resin composition of the present invention is excellent in moldability such as rapid curability and fluidity, and is excellent in heat resistance, low hygroscopicity, solder reflowability, flame retardancy and the like. When a cured product with excellent heat resistance is provided and applied to encapsulation of electronic components such as surface mount type semiconductor elements or printed circuit boards, excellent heat resistance, low moisture absorption, solder reflowability, flame retardancy Shows sex.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kazuhiko Nakahara 1st Tsukiji, Kisarazu-shi, Chiba Nippon Steel Chemical Co., Ltd. Electronic Materials Development Center (72) Inventor Masafumi Kaji 1st Tsukiji, Kisarazu-shi, Chiba Nippon Steel F-term in Electronic Materials Development Center, Chemical Co., Ltd. (reference) 4J036 AE05 AJ08 FB08 JA07

Claims (5)

[Claims] An epoxy resin represented by the following general formula (1): (Wherein, A represents a benzene ring, a naphthalene ring or a biphenyl ring which may be substituted with a hydrocarbon group having 1 to 6 carbon atoms, and R ₁ and R ₂ represent a hydrogen atom or a hydrocarbon having 1 to 6 carbon atoms. An aralkyl type epoxy resin (A) represented by the following general formula (A), wherein G is a glycidyl group, l is an integer of 1 or 2, and n is a number of 1 to 15. 2) (Wherein B represents a naphthalene ring which may be substituted with a hydrocarbon group having 1 to 6 carbon atoms, R ₃ and R ₄ represent a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, l and m is 1 or 2
And p represents a number of 1 to 15. And an aralkyl-type polyvalent hydroxy resin (B) having a softening point of 100 to 150 ° C and a melt viscosity at 150 ° C of 1 to 20 Pa · s. . 2. Aralkyl type epoxy resin (A) 100
Aralkyl-type polyhydroxy resin (B) based on parts by weight
An epoxy resin composition containing 40 to 150 parts by weight of 3. The aralkyl type epoxy resin (A) is 10 to 100% by weight of the total epoxy resin, and the aralkyl type polyvalent hydroxy resin (B) is 10 to 100% by weight of the total curing agent. 3. The epoxy resin composition according to 2. 4. The aralkyl type epoxy resin (A) is 80 to 100% by weight of the total epoxy resin, and the aralkyl type polyhydroxy resin (B) is 80 to 100% by weight of the total curing agent. 3. The epoxy resin composition according to 2. 5. A cured product obtained by curing the epoxy resin composition according to claim 1.