JPH10292091A - Epoxy resin composition and cured item thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an epoxy resin compsn. which gives a cured item resistant to high-temp. yellowing and excellent in heat resistance and which is suitable for sealing optical semiconductors by compounding an epoxy resin, an alcohol having a b.p. not lower than the curing temp. of the epoxy resin and an acid salt of an.org. base or an arom. compd. having a tert. nitrogen as a curative and cure accelerator. SOLUTION: The alcohol used is one pref. having a b.p. of 100 deg.C or higher, still pref. 150 deg.C or higher. The acid salt of an org. base is an onium salt (e.g. an org. phosphonium salt or an org. ammonium salt) or a tert.-nitrogen-contg. org. base (e.g. an org. acid salt of a cyclic base having an intracyclic tert. nitrogen atom or an org. salt of an imidazole compd.). The arom. compd. having a tert. nitrogen atom is a phenylated imidazole compd. or a tert-amino-substd. phenol. Based on the compsn., 0.01-30 wt.% alcohol and 0.01-5 wt.% cure accelerator are usually used.

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 light transmittance and suitable for optical semiconductor encapsulation, and an optical semiconductor device using the epoxy resin composition.

[0002]

2. Description of the Related Art Optical semiconductor elements include light receiving elements and light emitting elements such as LEDs (light emitting diodes), phototransistors, photodiodes, photocouplers, CCDs (charge coupled devices), EPROMs (erasable programmable read only memories), and photo sensors. For example, high-brightness red, orange, and green optical semiconductor elements have been developed as LEDs. As a sealing material for these optical semiconductor elements, compositions having excellent transparency are used in combination of various epoxy resins, curing agents, and curing accelerators.

[0003]

Recently, blue optical semiconductor elements have been developed in addition to these colors. This device emits blue light and generates considerably higher heat of 120 ° C. or more than devices of other colors.
There is a problem of yellowing that changes from yellow to yellow-brown at a high temperature of 0 ° C. or higher. JP-A-3-166221 discloses a tertiary amine or a specific tertiary amine as a curing accelerator in order to obtain an epoxy resin composition having excellent transparency in a combination of an epoxy resin, an acid anhydride-based curing agent and a curing accelerator. A method using the organic acid salt is described. At the same time, a method of using an organic acid metal salt such as tin octylate or zinc octylate and a tertiary amine together as a curing accelerator, a method of adding an organic phosphite or a hindered phenol as an anti-coloring agent, blue A method of performing "blueing" by adding a trace amount of a purple colorant is described. However, even when the epoxy resin compositions of these methods are used, there is a problem that yellowing occurs at a high temperature.
Furthermore, Japanese Patent Application Laid-Open No. 58-187426 discloses an epoxy resin composition using an epoxy resin, an alcohol compound, and an acid anhydride-based curing agent. There is a problem of doing. An object of the present invention is to develop a resin composition which gives a cured product having excellent heat resistance without yellowing at high temperatures.

[0004]

Means for Solving the Problems The present inventors have made intensive studies to achieve the above-mentioned object, and as a result, completed the present invention. That is, the present invention provides: (1) an epoxy resin, (B) an alcohol,
In the epoxy resin composition comprising (C) a curing agent and (D) a curing accelerator, the alcohol (B) is an alcohol having a boiling point equal to or higher than the curing temperature of the epoxy resin composition; Epoxy resin composition characterized in that the accelerator is an organic acid salt or an aromatic compound having tertiary nitrogen. (2) The epoxy resin according to (1), wherein the boiling point of alcohols in (B) is 100 ° C. or higher. (3) the epoxy resin composition of (1), wherein the alcohol of (B) has a boiling point of 150 ° C. or higher, and (4) the component (D) is an acid salt of an organic base. The epoxy resin composition according to any one of 3) (5) the epoxy resin composition according to (4), wherein the acid salt of the organic base is an organic onium salt or an organic acid salt of imidazoles; Phonium salt or organic ann (5) The epoxy resin composition according to any one of (1) to (3), wherein the component (D) is an aromatic compound having a tertiary nitrogen. The epoxy resin composition of (7), wherein the aromatic compound having a tertiary nitrogen is an imidazole having a phenyl group. (9) Component (A) in the epoxy resin composition is 25 to 70.
(1) to (8) wherein the component (B) is 0.01 to 30% by weight, the component (C) is 25 to 70% by weight, and the component (D) is 0.01 to 5% by weight. (10) A cured product of the epoxy resin composition of any one of (1) to (9), (11) an epoxy resin of any one of (1) to (9) (12) The optical semiconductor device according to (11), wherein the optical semiconductor device is a light emitting element or a light receiving element.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.

The epoxy resin of the component (A) used in the present invention is not particularly limited. For example, bisphenol A epoxy resin and / or bisphenol F epoxy resin having an epoxy equivalent of 2000 or less, N,
N-diglycidyl-o-toluidine, N, N-diglycidylaniline, phenylglycidyl ether, resorcinol diglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, polypropylene glycol diglycidyl ether, alicyclic (3,4-
Epoxy resins such as 3 ′, 4 ′ epoxycyclo) hexylmethylhexanecarboxylate are exemplified. Novolak-type epoxy resins include phenol, cresols,
Novolak resins using various phenols such as ethylphenols, butylphenols, octylphenols, bisphenol A, bisphenol F, bisphenol S, naphthols, phenol novolak resins containing a xylylene skeleton, phenol novolak resins containing a dicyclopentadiene skeleton, and a fluorene skeleton Examples of epoxy resins generally manufactured and sold, such as glycidyl etherified compounds of various novolak resins such as phenol novolak resins, include bisphenol A-type epoxy resins or bisphenol F-type epoxy resins having an epoxy equivalent of 2000 or less; N-diglycidyl-o-toluidine, N, N-diglycidylaniline, (3,4-
3 ', 4'epoxycyclo) hexylmethylhexanecarboxylate, hexahydrophthalic anhydride diglycidyl ester, hydrogenated bisphenol A type diglycidyl ether, tetrabromobisphenol A type epoxy resin,
Brominated cresyl glycidyl ether, ε-caprolactone-modified bisphenol A type epoxy resin, ε-caprolactone-modified (3,4-3 ′, 4 ′ epoxycyclo)
Hexylmethylhexanecarboxylate, phenol, a glycidyl etherified product of a phenol novolak resin containing a xylylene skeleton, a phenol novolak resin containing a dicyclopentadiene skeleton, and more preferably bisphenol A having an epoxy equivalent of 250 or less Epoxy resin and / or bisphenol F epoxy resin, (3,4-3 ′,
4 ′ epoxycyclo) hexylmethylhexanecarboxylate, hydrogenated bisphenol A type diglycidyl ether, ε-caprolactone modified bisphenol A type epoxy resin, ε-caprolactone modified (3,4-3 ′,
4 'epoxycyclo) hexylmethylhexanecarboxylate. These can be used alone or in combination of two or more. The amount used is usually 2 to the entire resin composition.
It is 5 to 70% by weight, preferably 35 to 60% by weight.

The alcohol (B) used in the present invention is not particularly limited as long as it has an boiling point higher than the curing temperature of the epoxy resin composition of the present invention. For example, at least one free hydroxyl group And the other hydroxyl group may be a polyhydric alcohol which may be etherified or esterified, or an aliphatic monoalcohol having 5 or more carbon atoms. The boiling point of the alcohols used in the present invention,
It is sufficient that the temperature be equal to or higher than the curing temperature of the epoxy resin composition, for example, 70 ° C. or higher, preferably 100 ° C. or higher, more preferably 150 ° C. or higher. The amount used is usually 0.01 to 30% by weight, preferably 0.1 to 20% by weight, based on the whole resin composition. In addition, alcohols can be used alone or in combination of two or more.

The preferred compounds among the alcohols (B) used in the present invention include, for example, the following formulas (1) to (1)
It is at least one selected from alcohols represented by (3).

[0009]

Embedded image

(Wherein, m represents an integer of 1 or more, R represents a hydrogen atom, an alkyl group or an acetyl group, and R ₀ represents a hydrogen atom or an alkyl group)

[0011]

Embedded image

(Wherein, R ₁ , R ₂ and R ₃ each independently represent a hydrogen atom, an alkyl group or an acetyl group, provided that R
_At least one of ₁ , R ₂ and R ₃ is a hydrogen atom. )

[0013]

_{Embedded image} C _n H _{2n + 1} -OH (3)

(Wherein, n represents an integer of 5 or more)

These include isomers such as structural isomers and optical isomers. In each of the above formulas, R,
As the alkyl group for R ₀ , R ₁ , R ₂ and R ₃ ,
A C1-C8 alkyl group, preferably, for example, a methyl group,
Examples thereof include C1 to C4 alkyl groups such as an ethyl group, a propyl group, and a butyl group. As the number of m, for example, 1 to 1
The number of 5 and n is preferably, for example, 5 to 15.
Preferred examples of the component (B) are as follows.

Examples of the compound of the formula (1) include ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol isoamyl ether, ethylene glycol monoacetate, diethylene glycol, diethylene glycol monomethyl ether, and diethylene glycol monomethyl ether. Compounds in which R ₀ is a hydrogen atom such as ethyl ether, diethylene glycol monobutyl ether, diethylene glycol monoacetate, triethylene glycol, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, tetraethylene glycol or polyethylene glycol, propylene glycol, propylene glycol Thing Ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, dipropylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, tripropylene glycol, R ₀ and tripropylene glycol monomethyl ether or polypropylene glycol with an alkyl group Certain compounds are mentioned.

Examples of the compound of the formula (2) include glycerin, glyceryl monoacetate and glyceryl diacetate, and examples of the compound of the formula (3) include n-hexanol, n-heptanol, n-octanol and n-octanol. -Decanol or n-dodecanol.

As the curing agent (C) used in the present invention, an acid anhydride type or phenol type is usually used. Acid anhydrides are
For example, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, trialkyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, nadic anhydride, methylnadic anhydride, heptonic anhydride , Hymic acid anhydride, 5-
(2,5-dioxotetrahydrofuryl) -3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride,
Alicyclic carboxylic anhydrides such as trialkyltetrahydrophthalic anhydride-maleic anhydride adduct, chlorendic acid, methylendmethylenetetrahydrophthalic anhydride, dodecenyl succinic anhydride, polyazelain anhydride, polysebacic anhydride, polydodecane Aliphatic carboxylic acid anhydrides such as diacid anhydride, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic anhydride, ethylene glycol trimellitic anhydride, biphenyltetracarboxylic anhydride And aromatic carboxylic acid anhydrides. Phenols include, for example, bisphenol A, tetrabromobisphenol A,
Bisphenol F, bisphenol S, 4,4'-biphenylphenol, 2,2'-methylene-bis (4-methyl-6-tert-butylphenol), 2,2'-
Methylene-bis (4-ethyl-6-tert-butylphenol), 4,4′-butylylene-bis (3-methyl-6-tert-butylphenol), 1,1,3-tris (2-methyl-4-hydroxy) -5-tert-butylphenol), trishydroxyphenylmethane,
Pyrogallol, phenols having a diisopropylidene skeleton, phenols having a fluorene skeleton such as 1,1-di-4-hydroxyphenylfluorene, polyphenol compounds such as phenolized polybutadiene, phenol, cresols, ethylphenols and butylphenols , Octylphenols, bisphenol A,
Various novolaks such as novolak resins, phenol novolak resins containing a xylylene skeleton, phenol novolak resins containing a dicyclopentadiene skeleton, and phenol novolak resins containing a fluorene skeleton using various phenols such as brominated bisphenol A, bisphenol F, bisphenol S, and naphthols. Resins. Of these curing agents, preferred are acid anhydrides, more preferred are methyltetrahydrophthalic anhydride, tetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, and hexahydrophthalic anhydride, and further preferred is methylhexahydrophthalic anhydride. Phthalic anhydride and hexahydrophthalic anhydride. These curing agents can be used alone or in combination of two or more. The amount used is usually 25 to 70% by weight, preferably 35 to 60% by weight, based on the whole resin composition.
% By weight.

The mixing ratio of the epoxy resin and the curing agent is as follows:
The curing agent is usually 0.5 to 1 chemical equivalent of epoxy resin.
It is mixed at a ratio of 1.6 equivalents, preferably from 0.7 to
It is 1.4 equivalents, more preferably mixed at a ratio of 0.9 to 1.2 equivalents.

The curing accelerator (D) used in the present invention includes an acid salt of an organic base or an aromatic compound having a tertiary nitrogen. Examples of the acid salt of an organic base include an organic onium salt such as an organic phosphonium salt and an organic ammonium salt, and an acid salt of an organic base having a tertiary nitrogen.

Examples of the organic phosphonium salt include phosphonium bromide having four phenyl rings such as tetraphenylphosphonium bromide and triphenylphosphine / toluene bromide. Examples of the organic ammonium salt include tetraoctyl ammonium bromide. , Tetrabutylammonium bromide, tetraethylammonium bromide, etc., and tetra (C1-C8) alkylammonium bromide. Examples of the acid salt of an organic base having a tertiary nitrogen include an alicyclic base having a tertiary nitrogen in the ring. And organic acid salts of various imidazoles. As the organic acid salt of an alicyclic base having a tertiary nitrogen in the ring, for example, a phenol salt of 1,8-diazabicyclo (5,4,0) undecene-7, 1,8
And salts of diaza compounds such as octylates of diazabicyclo (5,4,0) undecene-7 with phenols, polycarboxylic acids or phosphinic acids described below.

The organic acid salts of various imidazoles include:
For example, salts of imidazoles with organic acids such as polycarboxylic acids can be mentioned. Examples of imidazoles include, for example, 2
-Methylimidazole, 2-phenylimidazole, 2
-Undecylimidazole, 2-heptadecylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-phenylimidazole, 1-benzyl-2
-Methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole and the like. Preferred imidazoles include
For example, there may be mentioned the same imidazoles as the following phenyl-substituted imidazoles in aromatic compounds having a tertiary nitrogen. Examples of polyvalent carboxylic acids include phthalic acid,
Examples include aromatic polycarboxylic acids such as isophthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid, and naphthalenedicarboxylic acid, and aliphatic polycarboxylic acids such as maleic acid and oxalic acid. Preferred polycarboxylic acids include, for example, aromatic polycarboxylic acids such as terephthalic acid, trimellitic acid, and pyromellitic acid. Preferred salts of imidazoles with organic acids such as polycarboxylic acids include, for example, polycarboxylic acid salts of imidazoles having a substituent at the 1-position. More preferably,
For example, a trimellitic acid salt of 1-benzyl-2-phenylimidazole can be mentioned.

As the aromatic compound having a tertiary nitrogen,
For example, phenyl group-substituted imidazoles and tertiary amino group-substituted phenols can be mentioned. Examples of the phenyl-substituted imidazoles include 2-phenylimidazole, 2
-Phenyl-4-methylimidazole, 1-benzyl-
2-phenylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 2-phenyl-3,5-dihydroxymethylimidazole, 2-phenyl-4-hydroxymethyl-5
-Methylimidazole, 1-cyanoethyl-2-phenyl-3,5-dicyanoethoxymethylimidazole and the like. Preferred are, for example, imidazoles having an aromatic substituent at the 1-position. More preferred is, for example, 1-benzyl-2-phenylimidazole.

The tertiary amino group-substituted phenols include:
For example, di (C1-C4) alkylamino (C1-C2) such as 2,4,6-tri (dimethylaminomethyl) -phenol
C4) Phenols having 1 to 3 alkyl groups.

Further preferred curing accelerators include, for example, 1,8-diazabicyclo (5,4,0) undecene-7.
Phenol salt of 1,8-diazabicyclo (5,4,
0) Undecen-7 octylate, 2,4,6-tri (dimethylaminomethyl) -phenol, tetrabutylammonium bromide, tetraethylammonium bromide, 1-benzyl-2-phenylimidazole, 1-
Examples include benzyl-2-phenylimidazole trimellitate, tetraphenylphosphonium bromide, and triphenylphosphine / toluene bromide.

These curing accelerators can be used alone or in combination of two or more. The amount used is usually 0.01 to 5% by weight, preferably 0.03 to 3% by weight, based on the whole resin composition.

The epoxy resin composition of the present invention may optionally contain additives such as a coloring agent, an antioxidant, an ultraviolet absorber, and a release agent in addition to the above components (A) to (D). Can be blended. When the epoxy resin composition of the present invention is used for encapsulating an optical semiconductor device, these additives are used in amounts that do not substantially affect the transparency of the epoxy resin composition. These additives can be used alone or in combination of two or more.

The colorant is not particularly limited. Examples thereof include phthalocyanine, azo, disazo, quinacridone, anthraquinone, flavanthrone, perinone, perylene, dioxazine, condensed azo, azomethine or methine organic dyes, titanium oxide, and lead sulfate. And inorganic pigments such as zinc oxide, chrome yellow, zinc yellow, chrome vermillion, red iron oxide, cobalt purple, navy blue, ultramarine, carbon black, chrome green, chromium oxide, and cobalt green.

As the above antioxidant, for example, 2,6-
Dibutyl-p-cresol, 2,4,6-tri-ter
t-butylphenol, n-octadecyl-3- (4 ′
-Hydroxy-3 ', 5'-di-tert-butylphenol) propionate, styrenated phenol, 4-
Hydroxy-methyl-2,6-di-tert-butylphenol, 2,5-di-tert-butylhydroquinone, cyclohexylphenol, butylhydroxyanisole, 2,2′-methylenebis (4-methyl-6-t
ert-butylphenol, 1,1,3-tris (2-
Methyl-4-hydroxy-5-tert-cybutylphenyl) butane, 2,2′-thiobis (4-methyl-6-t
tert-butylphenol), 4,4′-thiobis (2
-Methyl-6-tert-butylphenol), phenolic antioxidants such as ethoxytrimethyldihydroquinoline, amine antioxidants such as N, N'-diphenyl-p-phenylenediamine, mercaptobenzothiazole, tetramethylthiuram monosulfide And sulfur-based antioxidants such as diphenyldecyl phosphite and tri (nonylphenyl) phosphite.

Examples of the ultraviolet absorber include 2-hydroxy-4-methoxybenzophenone and 2,2'-di-4-
Benzophenone ultraviolet absorbers such as hydroxymethoxybenzophenone, phenyl salicylate, 2,4-di-
salicylate UV absorbers such as tert-butylphenyl-3,5-dibutyl-4-hydroxybenzoate; (2′-hydroxy-3-tert-butyl-5 ′)
-Methylphenyl) -5-chlorobenzotriazole,
Benzotriazole UV absorbers such as (2'-hydroxy-5'-methylphenyl) benzotriazole, acrylonitrile UV absorbers such as ethyl-2-cyano-3-3'diphenylacrylate, nickel [2
2′-thiobis (4-tert-octyl) phenolate] -A metal complex salt ultraviolet absorber such as n-butylamine and nickel dibutylthiocarbamate;
Various ultraviolet absorbers such as hindered amine-based ultraviolet absorbers such as (6,6-tetramethylpiperidinyl) sebacate are exemplified.

Examples of the release agent include hydrocarbon lubricants such as paraffin wax, micro wax and polyethylene wax, higher fatty acid lubricants such as lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid and behenic acid, and stearylamide. Fatty acid amide-based lubricants such as palmitylamide, oleylamide, methylenebisstearamide, ethylenebisstearamide, hydrogenated castor oil, butyl stearate, ethylene glycol monostearate, pentaerythritol (mono-, di-, tri- -, Or tetra-) stearate or other higher fatty acid ester-based lubricant, cetyl alcohol, stearyl alcohol,
Polyethylene glycol, alcoholic lubricants such as polyglycerol, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, ricinoleic acid, magnesium such as naphthenic acid, calcium,
Cadmium, barium, zinc, metal soaps such as metal salts such as lead, carnauba wax, candelilla wax, beeswax, natural waxes such as montan wax, preferably, higher fatty acid esters, higher fatty acid amides,
Higher fatty acids, metal soaps, and hydrocarbon lubricants, more preferably zinc stearate, magnesium stearate, stearic acid, and pentaerythritol (mono-, di-, tri-, or tetra-) stearate.

The epoxy resin composition of the present invention comprises (A) an epoxy resin, (B) an alcohol, (C) a curing agent, (D) a curing accelerator, and, if necessary, a dye or pigment.
By weighing predetermined amounts of additives such as an antioxidant, an ultraviolet absorber and a release agent, and uniformly stirring them using a vacuum kneader or the like, a liquid composition can be easily obtained. In addition, in consideration of workability, two liquids of a main agent liquid containing an epoxy resin as a main component and a curing agent liquid mainly containing a curing agent and a curing accelerator can be used. However, alcohols can be used in both the base solution and / or the hardener solution.

The cured product of the epoxy resin composition of the present invention can be obtained by curing the above epoxy resin composition at a temperature of usually from 70 to 200 ° C., preferably from 80 to 160 ° C. The curing time is usually 15 minutes to 48 hours, preferably 3 minutes.
0 minutes to 36 hours. In addition, step curing is also suitable in some cases. In the present invention, the cured product of the resin is preferably a cured product having a thickness of 1 mm and having a light transmittance of 90% or more at a wavelength of 400 nm as measured by a spectrophotometer.

In the optical semiconductor device of the present invention, for example, the above-mentioned sufficiently defoamed epoxy resin composition is poured into a mold in which an optical semiconductor element is set, and is usually at 70 to 200 ° C.
Preferably, it can be obtained by heating and curing at 80 to 160 ° C. This sealing method is not particularly limited. As the optical semiconductor device of the present invention, for example, LE
D, an optical semiconductor device in which a light receiving element and a light emitting element such as a phototransistor, a photodiode, a photocoupler, a CCD, an EPROM, and a photosensor are sealed.

The optical semiconductor device of the present invention obtained as described above is excellent in heat resistance without yellowing at high temperatures.

[0036]

EXAMPLES Next, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

Example 1 110 g of methylhexahydrophthalic anhydride (Ricacid MH, manufactured by Shin Nippon Rika Co., Ltd.) as a curing agent, and tetraphenylphosphonium bromide (TPP-P) as a curing accelerator
(B, manufactured by Hokuko Chemical Industry Co., Ltd.) 0.5 g each is weighed, and heated and stirred using a vacuum kneader or the like to uniformly dissolve the curing accelerator in the curing agent. After cooling, 100 g of bisphenol A type epoxy resin (Epicoat 828, manufactured by Yuka Shell Co., epoxy equivalent 190) as an epoxy resin and ethylene glycol (manufactured by Wako Pure Chemical Industries, purity 99.0% or more) 10) 10 g of each was weighed and uniformly stirred using a vacuum kneader or the like to obtain 220.5 g of the epoxy resin composition of the present invention.

Examples 2 to 8 Epoxy resin compositions of the present invention were prepared according to the formulations shown in Table 1 and in the same manner as in Example 1 above. (In Table 1, the unit is g.)

Comparative Example 1 110 g of methylhexahydrophthalic anhydride (Ricacid MH, manufactured by Shin Nippon Rika Co., Ltd.) as a curing agent and tetraphenylphosphonium bromide (TPP-) as a curing accelerator
PB, manufactured by Hokko Chemical Industry Co., Ltd.)
The curing accelerator is uniformly dissolved by heating and stirring using a vacuum kneader or the like. It was cooled, and then a bisphenol A type epoxy resin (Epicoat 828, manufactured by Yuka Shell Co., Ltd., epoxy equivalent 1
90) 100 g was weighed, and uniformly stirred using a vacuum kneader or the like to obtain an epoxy resin composition for comparison.
5 g were obtained.

Comparative Examples 2 to 4 Comparative epoxy resin compositions were prepared in the same manner as in Comparative Example 1 using the formulations shown in Table 1.

Using the epoxy resin compositions prepared in Examples 1 to 8 and Comparative Examples 1 to 4, the gap was adjusted to 1 mm.
Each epoxy resin composition was poured into a gap between two glass plates, and 90 ° C. × 3 hours + 135 ° C. × 1 hour + 150 ° C. ×
The cured product was molded under the curing conditions of 5 hours. With respect to this, the light transmittance immediately after curing was set to 0 hour, and the light transmittance after 0 hour and after leaving at 140 ° C. for 1000 hours was measured using a spectrophotometer. The wavelength at which the light transmittance due to yellowing measured by a spectrophotometer decreases is around 400 nm. The measurement wavelength at this time is 600 nm and 800 n in addition to 400 nm.
m was also measured. The results are shown in Table 2 below. (In Table 2, the unit is%)

[0042]

[Table 1] Table 1 Example Comparative example 1 2 3 4 5 6 7 8 1 2 3 4 (A) component (A ₁ ) 100 100 100 40 40 40 40 100 40 40 40 (A ₂ ) 100 30 30 30 30 30 30 (A ₃ ) 100 30 30 30 30 30 30 (B) component (B ₁ ) 10 10 10 10 10 10 (B ₂ ) 10 (B ₃ ) 10 (C) component Curing agent * 4 90 125 70 90 90 110 110 110 110 110 110 110 (D) component (D ₁ ) 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 (D ₂ ) 0.5 0.5 (D ₃ ) 0.5 0.5

(A ₁ ): bisphenol A type epoxy resin (Epicoat 828 epoxy equivalent 190; manufactured by Yuka Shell Co.) (A ₂ ): alicyclic epoxy resin (Celoxide 2021)
Epoxy equivalent 133; manufactured by Daicel Chemical Industries, Ltd.) (A ₃ ): Alicyclic epoxy resin (ADEKARESIN EP40)
80 Epoxy equivalent 235; manufactured by Asahi Denka Co.) (B ₁ ) Ethylene glycol (manufactured by Wako Pure Chemical Industries, purity 99.0% or more) (B ₂ ) Propylene glycol (manufactured by Wako Pure Chemical Industries, Ltd.)
Purity 99.0% or more) (B ₃₎ Glycerin (manufactured by Wako Pure Chemical Industries, Ltd., purity 99.
(0% or more) Curing agent: Methylhexahydrophthalic anhydride (Ricacid MH, manufactured by Shin Nippon Rika Co., Ltd.) (D ₁ ): Tetraphenylphosphonium bromide (TPP-PB, manufactured by Hokuko Chemical Co., Ltd.) (D ₂ ): Tetrabutylammonium bromide (manufactured by Tokyo Chemical Industry Co., Ltd.) (D ₃ ): trimellitate of 1-benzyl-2-phenylimidazole (Curesol 1B2PZ · S; manufactured by Shikoku Chemical Industry Co., Ltd.)

[0044]

[Table 2] Table 2 Example Comparison Example 1 2 3 4 5 6 7 8 1 2 3 4 400 nm 0 hour 100 99 100 100 100 100 100 100 100 100 99 99 1000 hours 100 99 95 100 100 99 100 100 40 2 0 3 600 nm 0 hour 100 100 100 100 100 100 100 100 100 100 100 100 1000 hour 100 100 100 100 100 100 100 100 91 82 72 86 800 nm 0 hour 100 100 100 100 100 100 100 100 100 100 100 100 1000 hour 100 100 100 100 100 100 100 100 93 93 92 92

From the results shown in Table 2, it can be seen that the resin composition of the present invention has improved yellowing at high temperatures. Further 60
There was no change even at 0 nm and 800 nm, and it was confirmed that the film had extremely high heat resistance.

[0046]

According to the present invention, it is possible to obtain an epoxy resin composition which gives a cured product excellent in heat resistance without yellowing at high temperatures.

Claims (12)

[Claims] 1. An epoxy resin composition comprising (A) an epoxy resin, (B) an alcohol, (C) a curing agent, and (D) a curing accelerator, wherein the alcohol (B) is contained in the epoxy resin composition. Alcohols having a boiling point higher than the curing temperature, wherein the curing accelerator (D) is an organic base acid salt or 3
Resin composition characterized by being an aromatic compound having secondary nitrogen 2. The epoxy resin composition according to claim 1, wherein the alcohol (B) has a boiling point of 100 ° C. or higher. 3. The epoxy resin composition according to claim 1, wherein the alcohol (B) has a boiling point of 150 ° C. or higher. 4. The epoxy resin composition according to claim 1, wherein the component (D) is an acid salt of an organic base. 5. The epoxy resin composition according to claim 4, wherein the acid salt of the organic base is an organic onium salt or an organic acid salt of imidazoles. 6. The epoxy resin composition according to claim 5, wherein the organic onium salt is an organic phosphonium salt or an organic ammonium salt. 7. The epoxy resin composition according to claim 1, wherein the component (D) is an aromatic compound having a tertiary nitrogen. 8. The epoxy resin composition according to claim 7, wherein the aromatic compound having a tertiary nitrogen is an imidazole having a phenyl group. 9. The composition according to claim 1, wherein the component (A) in the epoxy resin composition is 25.
To 70% by weight, the component (B) is 0.01 to 30% by weight,
Component (C) is 25-70% by weight and component (D) is 0.0
The epoxy resin composition according to any one of claims 1 to 8, which is 1 to 5% by weight. 10. A cured product of the epoxy resin composition according to claim 1. 11. An optical semiconductor device encapsulated with the epoxy resin composition according to claim 1. 12. The optical semiconductor device according to claim 11, wherein the optical semiconductor device is a light emitting element or a light receiving element.