JP4678560B2 - Epoxy resin composition, cured product thereof, method for producing cured product, optical semiconductor sealing material, and optical semiconductor device - Google Patents

Description

  The present invention relates to an epoxy resin composition suitable for an optical semiconductor encapsulant, a cured product thereof, a method for producing the cured product, an optical semiconductor encapsulant, and an optical semiconductor device.

  Optical semiconductor devices such as LEDs, photocouplers, optical sensors, semiconductor lasers, and image sensors have been widely used in recent years as light-emitting elements or optical transmission devices. As resin materials for sealing optical semiconductor elements, aromatic epoxy resins and A two-component curing agent in combination with an acid anhydride curing agent is used because of its excellent molding processability and transparency.

  However, the sealing material using the above-described aromatic epoxy resin as a main agent tends to cause yellowing of a cured product due to absorption of an aromatic ring in the resin, and particularly in the LED field, the output of the LED element is increased and shortened. As the wavelength has progressed, the aromatic epoxy resin easily absorbs light of this short wavelength, causing yellowing of the optical semiconductor element and a decrease in light extraction efficiency.

  Therefore, a technique using an aliphatic cyclic epoxy compound such as 3,4-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexanecarboxylate as a main agent is known as an optical semiconductor sealing material with little yellowing of a cured product. (See Patent Document 1). However, even with such a non-aromatic compound, yellowing due to the thermal history of the cured product is inevitable, and in particular, the heat required for sealing materials for high-power type high-intensity LEDs that are in high demand in recent years. At present, stability has not been achieved. Further, when the optical semiconductor sealing material is required to have an appropriate flexibility, the sealing material mainly composed of the aliphatic cyclic epoxy compound has a drawback that an appropriate strength cannot be obtained because the cured product is hard and brittle. Had. In addition, since such an epoxy-curing sealing material requires a long time for the curing reaction, the productivity of the optical semiconductor device is inevitably lowered, and if it is excessively heated during the curing reaction in order to improve the curing speed. After all, the cured product was colored.

  Therefore, an ultraviolet curable sealing material is used because it is excellent in heat resistance and moisture resistance of the cured product and can be cured in a short time. For example, a vinyl ester of the aliphatic cyclic epoxy compound is used. A method of curing a chemical compound by radical polymerization is also known (see Patent Document 2 below). However, the use of a vinyl ester compound requires a step of reacting an aliphatic cyclic epoxy compound with methacrylic acid, which is not an advantageous means in view of industrial production. Since the reaction product with the above becomes a solid, it must be adjusted to a solution-like varnish when used as an optical semiconductor sealing material, and the design range of the material is narrow. It was difficult to cope with the significant expansion. In addition, the color of the cured product itself is severe, and the light extraction efficiency is low, making it difficult to put it into practical use as an LED sealing material.

JP-A-6-316626 JP 2006-332262 A

  Therefore, the problem to be solved by the present invention is an epoxy which is excellent in fluidity in the varnish state, excellent in transparency of the cured product and heat-resistant yellowing after heat history, and also excellent in strength of the cured product. The object is to provide a resin composition.

  As a result of intensive investigations to solve the above problems, the inventors of the present invention react and cure a composition containing an epoxy resin, methacrylic acid, and a specific acid group-containing radical polymerizable monomer at a time. In other words, by curing by an in situ reaction, the present invention has been found by having excellent fluidity before curing, and exhibiting excellent transparency, heat-resistant yellowing, and strength after curing. It came to do.

That is, the present invention relates to an epoxy resin (A) having a cycloaliphatic structure , methacrylic acid (B), an acid group-containing radical polymerizable monomer (C) having an aliphatic ester bond or an aliphatic carbonate bond , radical polymerization The present invention relates to an epoxy resin composition comprising an initiator (D) and an aliphatic cyclic structure-containing monomethacrylate compound (E) as essential components.

  An optical semiconductor sealing material comprising the above epoxy resin composition.

The present invention further relates to a cured product obtained by shaping the transparent epoxy resin composition and then curing it by heating or irradiation with active energy rays.
The present invention further relates to a method for producing a cured product, wherein the transparent epoxy resin composition is shaped and then cured by heating or irradiation with active energy rays.
The present invention further relates to an optical semiconductor device characterized in that an optical semiconductor is sealed with the transparent epoxy resin composition.

  According to the present invention, there is provided an epoxy resin composition that is excellent in fluidity in a varnish state, is excellent in yellowing resistance after heat history of a cured product, and further exhibits excellent mechanical strength. There is.

Hereinafter, the present invention will be described in detail.
As described above, the epoxy resin composition of the present invention includes an epoxy resin (A), methacrylic acid (B), an acid group-containing radical polymerizable monomer (C) having an aliphatic ester bond or an aliphatic carbonate bond, and The radical polymerization initiator (D) is an essential component, and the reaction between the epoxy group and the acid group and the polymerization reaction of the radical polymerizable group are performed continuously or simultaneously. By curing in-situ reaction in this way, the fluidity of the epoxy resin composition containing the epoxy resin and the curing agent as essential components can be improved before curing, and the heat-resistant yellowing and strength of the cured product are dramatically improved. It is a point that should be noted that it is improved.

The epoxy resin (A) having a cycloaliphatic structure used in the present invention is 2- (3,4-epoxy) cyclohexyl-5,5-spiro- (3,4-epoxy) cyclohexane-m-dioxane, 3,4 -Epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 3,4-epoxy-6-methylcyclohexylmethyl-3,4-epoxy-6-methylcyclohexanecarboxylate, vinylcyclohexane dioxide, bis (3,4- Epoxycyclohexylmethyl) adipate, bis (3,4-epoxy-6-methylcyclohexylmethyl) adipate, exo-exobis (2,3-epoxycyclopentyl) ether, 2,2-bis (4- (2,3-epoxy) Propyl) cyclohexyl) propane, 2,6-bis (2 3-epoxypropoxycyclohexyl-p-dioxane), 2,6-bis (2,3-epoxypropoxy) norbornene, diglycidyl ether of linoleic acid dimer, limonene dioxide, 2,2-bis (3,4- Epoxycyclohexyl) propane, dicyclopentadiene dioxide, o- (2,3-epoxy) cyclopentylphenyl-2,3-epoxypropyl ether, 1,2-bis [5- (1,2-epoxy) -4,7 -Hexahydromethanoindanxyl] ethane, cyclohexanediol diglycidyl ether, diglycidyl hexahydrophthalate and the like.

  Next, as described above, the methacrylic acid (B) used in the present invention reacts with the epoxy resin (A), and at the same time, causes acryloyl group polymerization by radical polymerization. In the present invention, the heat yellowing can be drastically improved by performing the curing using such an in-situ reaction.

  The acid group-containing radical polymerizable monomer (C) having an aliphatic ester bond or an aliphatic carbonate bond used in the present invention improves the light extraction efficiency by improving the transparency of the cured product and is suitable for the cured product. It is an essential component for imparting flexibility and improving strength. The acid group-containing radical polymerizable monomer (C) is specifically represented by the following structural formula (1) from the viewpoint of compatibility with the epoxy resin (A).

（式中、Ｒ^１は炭素原子数２〜１０の脂肪族炭化水素基、Ｘはエステル結合又はカーボネート結合、Ｒ^２は炭素原子数２〜１０の脂肪族炭化水素基を表し、ｎは１〜５の整数を示す。）で表されるものが好ましい。

(In the formula, R ¹ represents an aliphatic hydrocarbon group having 2 to 10 carbon atoms, X represents an ester bond or a carbonate bond, R ² represents an aliphatic hydrocarbon group having 2 to 10 carbon atoms, and n represents 1 to 1) An integer of 5 is preferred).

  Here, as the compound having an ester bond as X in the structural formula (1), a compound obtained by reacting a hydroxyalkyl (meth) acrylate with an aliphatic polycarboxylic acid having 2 to 10 carbon atoms, And a compound obtained by reacting a hydroxyalkyl (meth) acrylate, an aliphatic diol having 2 to 10 carbon atoms, and an aliphatic polyvalent carboxylic acid having 2 to 10 carbon atoms.

  Here, examples of the hydroxyalkyl (meth) acrylate include β-hydroxyethyl methacrylate and β-hydroxyethyl acrylate. Examples of the aliphatic polyvalent carboxylic acid include succinic anhydride, adipic acid, maleic anhydride, tetrahydrophthalic acid, and cyclohexanedicarboxylic acid.

  Furthermore, as the aliphatic diol having 2 to 10 carbon atoms, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 2-methyl-1,3-propanediol, 2,2-dimethyl-1,3-propane Diol, 3-methyl-1,5-pentanediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 1,2-cyclohexanediethanol, 1,3-cyclohexanedie Nord, 1,4-cyclohexane diethanol, and the like. Of these, butanediol, pentanediol, hexanediol, cyclohexanediol, and cyclohexanedimethanol having 4 to 8 carbon atoms are preferred from the viewpoint of excellent compatibility with the epoxy resin (A).

  Moreover, as what has a carbonate bond as X in the said Structural formula (1), after obtaining polycarbonate diol by transesterification of C2-C10 aliphatic diol and dialkyl carbonate, for example, (meth) acryl The compound obtained by making it react with an acid or its derivative (s) is mentioned.

Here, as the aliphatic diol having 2 to 10 carbon atoms, for example, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6- Hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 2-methyl-1,3-propanediol, 2,2-dimethyl-1, 3-propanediol, 3-methyl-1,5-pentanediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexane Dimethanol, 1,4-cyclohexanedimethanol, 1,2-cyclohexanediethanol, 1,3-cyclohexane Sanji ethanol, those having 3 to 10 carbon atoms such as 1,4-cyclohexane diethanol, and the like. Of these, butanediol, pentanediol, hexanediol, cyclohexanediol, and cyclohexanedimethanol having 4 to 8 carbon atoms are preferred from the viewpoint of excellent compatibility with the epoxy resin (A).
On the other hand, examples of the dialkyl carbonate include dimethyl carbonate from the viewpoint of reactivity.

  Among these, X is preferably an ester bond in the structural formula (1) from the viewpoint that moderate hardness can be imparted to the cured product, in particular, β-hydroxyethyl methacrylate and succinic anhydride. Preference is given to 3-[[2- (methacryloyloxy) ethoxy] carbonyl] propionic acid which is an adduct, and 2-methacryloyloxyethyl hexahydrophthalic acid which is an adduct of β-hydroxyethyl methacrylate and hexahydrophthalic acid.

  The blending ratios of the epoxy resin (A), methacrylic acid (B), and acid group-containing radically polymerizable monomer (C) having an aliphatic ester bond or an aliphatic carbonate bond detailed above are specifically The epoxy resin (A) is 10 to 60 parts by mass, the methacrylic acid (B) is 1 to 35 parts by mass, and the acid having an aliphatic ester bond or an aliphatic carbonate bond with respect to 100 parts by mass in total. It is preferable that the group-containing radically polymerizable monomer (C) is blended at a ratio of 5 to 50 parts by mass from the viewpoint that the heat-resistant yellowing and strength balance of the cured product is good.

  The radical polymerization initiator (D) used in the present invention is not particularly limited as long as it is used as a thermal radical polymerization initiator. For example, methyl ethyl ketone peroxide, methylcyclohexanone peroxide, methyl acetoacetate peroxide, acetylacetone peroxide, 1, 1-bis (t-butylperoxy) 3,3,5-trimethylcyclohexane, 1,1-bis (t-hexylperoxy) cyclohexane, 1,1-bis (t-hexylperoxy) 3,3,5 -Trimethylcyclohexane, 1,1-bis (t-butylperoxy) cyclohexane, 2,2-bis (4,4-di-t-butylperoxycyclohexyl) propane, 1,1-bis (t-butylperoxy) ) Cyclododecane, n-butyl 4,4-bis (t-butyl pero) B) Valerate, 2,2-bis (t-butylperoxy) butane, 1,1-bis (t-butylperoxy) -2-methylcyclohexane, t-butyl hydroperoxide, P-menthane hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, t-hexyl hydroperoxide, dicumyl peroxide, 2,5-dimethyl-2,5-bis (t-butylperoxy) hexane, α, α '-Bis (t-butylperoxy) diisopropylbenzene, t-butylcumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-bis (t-butylperoxy) hexyne-3, Isobutyryl peroxide, 3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide Id, lauroyl peroxide, cinnamic acid peroxide, m-toluoyl peroxide, benzoyl peroxide, diisopropyl peroxydicarbonate, bis (4-t-butylcyclohexyl) peroxydicarbonate, di-3-methoxybutylperoxy Dicarbonate, di-2-ethylhexylperoxydicarbonate, di-sec-butylperoxydicarbonate, di (3-methyl-3-methoxybutyl) peroxydicarbonate, di (4-t-butylcyclohexyl) peroxy Dicarbonate, α, α′-bis (neodecanoylperoxy) diisopropylbenzene, cumylperoxyneodecanoate, 1,1,3,3-tetramethylbutylperoxyneodecanoate, 1-cyclohexyl- 1-methyl Ethyl peroxyneodecanoate, t-hexylperoxyneodecanoate, t-butylperoxyneodecanoate, t-hexylperoxypivalate, t-butylperoxypivalate, 2,5-dimethyl- 2,5-bis (2-ethylhexanoylperoxy) hexane, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, 1-cyclohexyl-1-methylethylperoxy-2-ethyl Hexanoate, t-hexylperoxy-2-ethylhexanoate, t-butylperoxy-2-ethylhexanoate, t-butylperoxyisobutyrate, t-butylperoxymaleic acid, t- Butyl peroxylaurate, t-butyl peroxy-3,5,5-trimethylhexanoate, t-butylperoxyisopropyl monocarbonate, t-butylperoxy-2-ethylhexyl monocarbonate, 2,5-dimethyl-2,5-bis (benzoylperoxy) hexane, t-butylperoxyacetate, t-hexylper Oxybenzoate, t-butylperoxy-m-toluoylbenzoate, t-butylperoxybenzoate, bis (t-butylperoxy) isophthalate, t-butylperoxyallyl monocarbonate, 3,3 ′, 4,4 Examples include '-tetra (t-butylperoxycarbonyl) benzophenone. The radical polymerization initiator (D) is used in an amount of 0.001% by mass to 2% by mass with respect to the total mass of the radical polymerizable component and the total mass of the radical polymerization initiator (D). Preferably it is done.

In the epoxy resin composition of the present invention, it is preferable to use an aliphatic cyclic structure-containing monomethacrylate compound (E) in addition to the above-described components from the viewpoint that heat-resistant yellowing of the cured product can be further improved. Specific examples of the aliphatic cyclic structure-containing monomethacrylate compound (E) include dicyclopentanyl methacrylate, dicyclopentenyloxyethyl methacrylate, 1,2-epoxy-4-vinylcyclohexane, and 3,4-epoxycyclohexylmethyl. Examples include methacrylate, cyclohexyl methacrylate, 2-methylcyclohexyl methacrylate, isobornyl methacrylate and the like. Among these, in particular, a compound selected from the group consisting of dicyclopentanyl methacrylate, 1,2-epoxy-4-vinylcyclohexane, 3,4-epoxycyclohexylmethyl methacrylate, cyclohexyl methacrylate, and isobornyl methacrylate, This is preferable because the mechanical strength of the cured product is further improved.

  The proportion of the aliphatic cyclic structure-containing monomethacrylate compound (E) used here is an epoxy resin (A), methacrylic acid (B), an acid group-containing radical polymerizable monomer having an aliphatic ester bond or an aliphatic carbonate bond. Hardened | cured material that it is a ratio used as 20-70 mass parts with respect to 100 mass parts of synthetic | combination masses of a body (C) and an alicyclic structure containing monomethacrylate compound (E), especially 40-60 mass parts. It is preferable in terms of strength.

  The transparent epoxy resin composition of the present invention can further improve the light resistance and heat yellowing of the cured product by using the reactive silicone (F) in addition to the above-described components. Such reactive silicone (F) has an amino group, an epoxy group, an alicyclic epoxy group, a carbinol-based hydroxyl group, a silanol-based hydroxyl group, a methacryloyl group, a polyether alcohol group, a mercapto group, and a carboxyl group in part of the polysiloxane structure. And those containing a reactive functional group selected from the group.

  More specifically, the following structural formula (2)

ここで、上記式（２）中、Ｒ^１及びＲ^２は、それぞれ独立的にメチル基又は水素原子を表す。また、上記式（２）中、Ｘ、Ｘ’、及びＸ”は、それぞれ独立的に、下記構造式ａ〜ｈからなる群から選択される反応性基、又は、メチル基又は水素原子を表し、ｘ及びｙは１以上の整数である。また、ｘ及びｙの合計は２〜１００となる範囲である。

Here, in said formula (2), R < ¹ > and R < ² > represents a methyl group or a hydrogen atom each independently. In the formula (2), X, X ′, and X ″ each independently represent a reactive group selected from the group consisting of the following structural formulas a to h, a methyl group, or a hydrogen atom. , X and y are integers of 1 or more, and the total of x and y is in the range of 2-100.

  Here, X, X ′, and X ″ are the reactive groups, and R in the structural formulas a to g represents an alkylene group having 1 to 4 carbon atoms.

  Among these, a polysiloxane having an epoxy group, a carboxyl group, or a methacryloyl group is particularly preferable from the viewpoint of excellent reactivity.

  The amount of the reactive silicone (F) used is an epoxy resin (A), methacrylic acid (B), an acid group-containing radical polymerizable monomer (C) having an aliphatic ester bond or an aliphatic carbonate bond, and the reaction. It is preferable from the point which light resistance and heat-resistant yellowing improve further that it is the range of 5-30 mass parts with respect to a total of 100 mass parts of photosensitive silicone (F).

  The epoxy resin composition of the present invention can further use a curing accelerator as appropriate. Various curing accelerators can be used, and examples thereof include phosphorus compounds, tertiary amines, imidazoles, organic acid metal salts, Lewis acids, and amine complex salts. In particular, when used as an optical semiconductor sealing material application, from the viewpoint of excellent curability, heat resistance, electrical properties, moisture resistance reliability, etc., phosphorous compounds are triphenylphosphine, and tertiary amines are 1,8- Diazabicyclo- [5.4.0] -undecene (DBU) is preferred.

  In the epoxy resin composition of the present invention, a radically polymerizable polyfunctional monomer may be used in combination as appropriate from the viewpoint that the heat resistance of the cured product becomes higher and the balance of physical properties can be adjusted. The radical polymerizable polyfunctional monomers that can be used here are dipentaerythritol hexaacrylate, dipentaerythritol pentaacrylate, dipentaerythritol tetraacrylate, dipentaerythritol triacrylate, pentaerythritol tetraacrylate, pentaerythritol triacrylate, neopentyl glycol. Examples include diacrylate, trimethylolpropane trimethacrylate, ethylenediaminetetramethacrylate, hexanediacrylate, and dipentaerythritol pentavinylate. The amount of these radically polymerizable polyfunctional monomers used is preferably in the range of 1 to 10% by mass in the composition.

  Moreover, the epoxy resin composition of this invention is preferable at the point which can mix the antioxidant in addition to said each component, can prevent the oxidative degradation at the time of a heating, and the cured | curing material excellent in transparency is obtained.

  Examples of the antioxidant that can be used here include 2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-butyl-p-ethylphenol, and stearyl-β. -(3,5-di-t-butyl-4-hydroxyphenyl) propionate, monophenols such as 4-methoxynaphthol, hydroquinone, 2,2'-methylenebis (4-methyl-6-t-butylphenol), 2 , 2'-methylenebis (4-ethyl-6-t-butylphenol), 4,4'-thiobis (3-methyl-6-t-butylphenol), 4,4'-butylidenebis (3-methyl-6-t-) Butylphenol), 3,9-bis [1,1-dimethyl-2- {β- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy} ethyl Bisphenols such as 2,4,8,10-tetraoxaspiro [5,5] undecane, 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, tetrakis- [methylene-3- (3 ′, 5′-di-t-butyl) -4′-hydroxyphenyl) propionate] methane, bis [3,3′-bis- (4′-hydroxy-3′-t-butylphenyl) butyric acid] glycol ester, 1,3,5-tris (3 Phenols represented by polyfunctional phenols such as', 5'-di-t-butyl-4'-hydroxybenzyl) -S-triazine-2,4,6- (1H, 3H, 5H) trione, tocophenol System antioxidants; -Quinone antioxidants typified by benzoquinone, tolquinone, naphthoquinone; dilauryl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropio Sulfur-based antioxidants such as nitrates; triphenyl phosphite, diphenylisodecyl phosphite, phenyl diisodecyl phosphite, tris (nonylphenyl) phosphite, diisodecylpentaerythritol phosphite, tris (2,4-di-t-butyl Phenyl) phosphite, cyclic neopentanetetraylbis (octadecyl) phosphite, cyclic neopentanetetraylbi (2,4-di-t-butylphenyl) phosphite, cyclic neopentanetetraylbi (2,4- J-t-B Phosphites such as til-4-methylphenyl) phosphite, bis [2-tert-butyl-6-methyl-4- {2- (octadecyloxycarbonyl) ethyl} phenyl] hydrogen phosphite, 9,10- Dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10- (3,5-di-t-butyl-4-hydroxybenzyl) -9,10-dihydro-9-oxa-10-phosphaphenanthrene Examples thereof include phosphorus-based antioxidants typified by oxaphosphaphenanthrene oxides such as -10-oxide, 10-decyloxy-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide. It is preferable that the usage-amount of above-mentioned antioxidant is the range used as 0.005-1 mass part with respect to 100 mass parts of all the hardening components.

  The epoxy resin composition of the present invention can be further improved in light resistance by further incorporating an ultraviolet absorber. Examples of ultraviolet absorbers that can be blended include salicylic acids such as phenyl salicylate, pt-butylphenyl salicylate, p-octylphenyl salicylate; 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4 -Octoxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2-hydroxy-4-methoxy- Benzophenones such as 5-sulfobenzophenone; 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-5′-tert-butylphenyl) benzotriazole, 2- (2 ′ -Hydroxy-3 ', '-Di-tert-butylphenyl) benzotriazole, 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3', 5′-ditert-butylphenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-3 ′, 5′-ditert-amylphenyl) benzotriazole, 2-{(2′-hydroxy-3 ′ Benzotriazoles such as 3 ", 4", 5 ", 6" -tetrahydrophthalimidomethyl) -5'-methylphenyl} benzotriazole; bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate Bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) [{3 5- bis (1,1-dimethylethyl) -4-hydrido hydroxyphenyl} hindered amines such as methyl] butyl malonate and the like. It is preferable that the compounding quantity of these ultraviolet absorbers shall be 0.1-10 mass parts with respect to 100 mass parts of all the hardening components.

  In addition to the above components, a colorant, a coupling agent, a leveling agent, a release agent, a lubricant, and the like can be appropriately added to the epoxy resin composition of the present invention depending on the purpose.

  The colorant is not particularly limited, for example, phthalocyanine, azo, disazo, quinacridone, anthraquinone, flavantron, perinone, perylene, dioxazine, condensed azo, azomethine-based various organic pigments, titanium oxide, lead sulfate, chromium yellow, zinc yellow Inorganic pigments such as chrome vermilion, valve shell, cobalt violet, bitumen, ultramarine, carbon black, chrome green, chromium oxide, cobalt green and the like can be mentioned.

  Examples of the leveling agent include oligomers having a molecular weight of 4000 to 12000 made of acrylates such as ethyl acrylate, butyl acrylate, and 2-ethylhexyl acrylate, epoxidized soybean fatty acid, epoxidized abiethyl alcohol, hydrogenated castor oil, and titanium-based coupling agent. Etc. Examples of the lubricant include hydrocarbon lubricants such as paraffin wax, microwax and polyethylene wax, higher fatty acid lubricants such as lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid and behenic acid, stearylamide, palmitylamide Higher fatty acid amide lubricants such as oleylamide, methylenebisstearamide, ethylenebisstearamide, hydrogenated castor oil, butyl stearate, ethylene glycol monostearate, pentaerythritol (mono-, di-, tri-, or tetra -) Higher fatty acid ester lubricants such as stearate, alcohol lubricants such as cetyl alcohol, stearyl alcohol, polyethylene glycol, polyglycerol, lauric acid, myristic acid, palmitic acid, stearic acid, arachidin , Behenic acid, ricinoleic acid, such as magnesium naphthenate, calcium, metal soaps is cadmium, barium, zinc, metal salts such as lead, carnauba wax, candelilla wax, beeswax, and natural waxes such as montan wax.

  As the coupling agent, for example, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxy Silane, N- (2-aminoethyl) 3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) 3-aminopropylmethyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane , Vinyltrimethoxysilane, N- (2- (vinylbenzylamino) ethyl) 3-aminopropyltrimethoxysilane hydrochloride, 3-methacryloxypropyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropylto Silane coupling agents such as limethoxysilane, isopropyl (N-ethylaminoethylamino) titanate, isopropyl triisostearoyl titanate, titanium di (dioctyl pyrophosphate) oxyacetate, tetraisopropyl di (dioctyl phosphite) titanate, neo Titanium coupling agents such as alkoxytri (p-N- (β-aminoethyl) aminophenyl) titanate, Zr-acetylacetonate, Zr-methacrylate, Zr-propionate, neoalkoxyzirconate, neoalkoxytrisneodecanoyl Zirconate, Neoalkoxytris (dodecanoyl) benzenesulfonyl zirconate, Neoalkoxytris (ethylenediaminoethyl) zirconate, Neoalkoxytris (m-aminophenyl) Rukoneto, ammonium zirconyl Niu arm carbonate, Al- acetylacetonate, Al- methacrylate, zirconium or the like Al- propionate, or Aluminum-based coupling agents is preferably silicon-based coupling agent. By using a coupling agent, moisture-reliability is excellent, and a cured product with little decrease in adhesive strength after moisture absorption can be obtained.

  Release agents include hydrocarbon lubricants such as paraffin wax, microwax, polyethylene wax, higher fatty acid lubricants such as lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, and behenic acid, stearylamide, palmityl. Higher fatty acid amide type lubricants such as amide, oleylamide, methylene bisstearamide, ethylene bisstearamide, hydrogenated castor oil, butyl stearate, ethylene glycol monostearate, pentaerythritol (mono-, di-, tri-, or Higher fatty acid ester lubricants such as tetra-) stearate, alcohol lubricants such as cetyl alcohol, stearyl alcohol, polyethylene glycol, polyglycerol, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, Examples include metal soaps such as magnesium, calcium, cadmium, barium, zinc, lead and other metal salts such as hemonic acid, ricinoleic acid and naphthenic acid, and natural waxes such as carnauba wax, candelilla wax, beeswax and montan wax, preferably Higher fatty acid esters, higher fatty acid amides, higher fatty acids, metal soaps, hydrocarbon lubricants, more preferably zinc stearate, magnesium stearate, stearic acid, pentaerythritol (mono-, di-, tri-, Or tetra-) stearate.

  The epoxy resin composition of the present invention can be made into a liquid optical semiconductor encapsulant by uniformly stirring the above-described components.

  As described above, the curing reaction of the epoxy resin composition of the present invention can be performed simultaneously or continuously without distinguishing the reaction between the epoxy group and the acid group and the polymerization reaction of the radical polymerizable group as a reaction step. In other words, it is cured by an in situ reaction. The specific curing temperature is preferably in the temperature range of 50 to 200 ° C., in particular, after being cured at 50 to 100 ° C. to form a tack-free cured product, further at a temperature condition of 120 to 180 ° C. It is preferable to process.

  As described above, the composition of the present invention described in detail is excellent in transparency, yellowing resistance, particularly heat-resistant yellowing, and excellent in fluidity before curing, so that LED, phototransistor, photodiode, photocoupler It is useful as a sealing material for various optical semiconductor devices such as CCDs, EPROMs, and photosensors, and is particularly useful as a sealing material for high-brightness LED elements that generate significant heat during light emission. Here, the high-brightness LED element means an element having a luminous flux of 100 lumens (lm) or more.

  As the high-brightness LED, a blue to white LED having a main light emission peak at a wavelength of 350 to 550 nm and a compound semiconductor composed of four elements of aluminum, gallium, indium, and phosphorus are used, and the element composition is adjusted. And quaternary LEDs that enable red, orange, yellow, and yellow-green color development.

As the application of the former blue to white LED having a main emission peak at a wavelength of 350 to 550 nm, it is used for a backlight source for liquid crystal panels used in portable DVD players, car navigation systems, laptop computers, etc. 10 -17 type liquid crystal panel backlight light source, automobile headlamp light source, and the like.
On the other hand, the use of quaternary LEDs includes outdoor displays, rear lamps and interior lighting of automobiles, backlights of liquid crystal displays of thin televisions and personal computers.

  The optical semiconductor device of the present invention can be obtained by sealing an optical semiconductor and an electrode member bonded thereto with the epoxy resin composition. Specifically, the epoxy resin composition that has been sufficiently degassed is sealed with an epoxy resin composition of the present invention on an optical semiconductor to which an electrode member such as a lead wire is attached by a molding method such as transfer molding or casting. And a method of curing, a method of mounting an optical semiconductor on a circuit board in advance, sealing it with the epoxy resin composition of the present invention, and a method of curing. Specifically, it can be obtained by pouring into a mold set with an optical semiconductor element, followed by heat curing under the above temperature conditions.

  The optical semiconductor device of the present invention includes various optical semiconductor devices enumerated as applications of the above-described epoxy resin composition, specifically, light receiving elements such as LEDs, phototransistors, photodiodes, photocouplers, CCDs, EPROMs, and photosensors. And an optical semiconductor device in which a light emitting element or the like is sealed. Among these, LED devices, particularly high-intensity LED devices are particularly preferable, and blue to white LED devices having a main emission peak at a wavelength of 350 to 550 nm and quaternary LED devices are particularly preferable.

Next, the present invention will be specifically described with reference to Examples and Comparative Examples. In the following, “parts” and “%” are based on weight unless otherwise specified. In addition, each physical property evaluation was measured on condition of the following.
1) Varnish viscosity: Measured at 25 ° C. using an E-type viscometer (“TV-20 type” cone plate type manufactured by Toki Sangyo Co., Ltd.).
2) Light transmittance: Measured using a spectrophotometer “UV-3150” (manufactured by Shimadzu Corporation).
3) Heat-resistant deterioration: The light transmittance at a wavelength of 400 nm of the cured epoxy resin after heating at 150 ° C. for 72 hours was measured.
4) UV resistance: light transmission at a wavelength of 400 nm of the cured product after irradiation with UV light for 1000 h at an irradiation intensity of 490 W / m ² and a black panel temperature of 63 ° C. using a fade meter (manufactured by Suga Test Instruments Co., Ltd.) The rate was measured.
5) Flexural strength, flexural modulus: compliant with JIS6911.
6) Storage stability: Viscosity was measured after the varnish was stored at 25 ° C. for 2 weeks.

Examples 1-8, Comparative Examples 3 and 4
According to the formulation shown in Table 1 or 2 below, an epoxy resin and various carboxylic acids, a polymerizable compound, a radical polymerization initiator, a curing accelerator, and the like were blended using a stirrer to obtain an epoxy resin composition. Varnish viscosity and storage stability were evaluated using this epoxy resin composition.
In addition, this epoxy resin composition is poured into a gap of a mold in which a spacer (silicone tube) having a thickness of 3 mm is sandwiched between glass plates, cured at 80 ° C. for 2 hours, and the cured product is taken out from the mold to become tack-free. Then, the temperature was further raised to 160 ° C., and after reaching 160 ° C., the cured product was obtained by holding at that temperature for 2 hours, and various evaluation tests were performed using this as a test piece. . The results are shown in Tables 1 and 2.

Comparative Examples 1 and 2
Each component was blended according to the blending shown in Table 2 below, and blended using a stirrer to obtain an epoxy resin composition. Varnish viscosity and storage stability were evaluated using this epoxy resin composition.
Further, this epoxy resin composition was poured into the gap of the mold used in Example 1, cured at 110 ° C. for 2 hours, the cured product was taken out from the mold, further heated to 165 ° C., and reached 165 ° C. Then, it hold | maintained at this temperature for 2 hours, the hardened | cured material was obtained, and various evaluation tests were done using this as a test piece. The results are shown in Table 2.

上記表１及び表２中、「貯蔵安定性」は、エポキシ樹脂組成物を調整した後、２週間後の粘度が２００ｍＰａ・Ｓ以下のものを「○」、２００ｍＰａ・Ｓを超えるものを「×」とした。

In Tables 1 and 2 above, “storage stability” is “○” when the viscosity after two weeks after adjusting the epoxy resin composition is 200 mPa · S or less, and “×” when the viscosity exceeds 200 mPa · S. "

In addition, each component shown in the said Table 1 and Table 2 is as follows.
Alicyclic epoxy resin: (3,4-epoxycyclohexane) methyl-3 ′, 4′-epoxycyclohexyl-carboxylate (trade name “Celoxide 2021P”, manufactured by Daicel Chemical Industries, Ltd.)
Bisphenol A type epoxy resin: Epoxy equivalent 188 g / eq. Bisphenol A epoxy resin (trade name “EPICLON 850S”, manufactured by DIC Corporation)
Hydrogenated bisphenol A type epoxy resin: Hydrogenated bisphenol A type epoxy resin (trade name “EPICLON EXA-7015” epoxy equivalent 200 g / eq., Manufactured by DIC Corporation)
HO-MS: 3-[[2- (methacryloyloxy) ethoxy] carbonyl] propionic acid (trade name “Light Ester HO-MS”, manufactured by Kyoeisha Chemical Co., Ltd.)
HO-HH: 2-methacryloyloxyethyl hexahydrophthalic acid (trade name “Light Ester HO-HH”, manufactured by Kyoeisha Chemical Co., Ltd.)
Dicyclopentanyl methacrylate: Trade name “Fancryl FA-513M” manufactured by Hitachi Chemical Co., Ltd. Reactive silicone: Methacrylic group-containing silicone oil (trade name “X-22-164A” manufactured by Shin-Etsu Chemical)
Peroxide: 1,1-di (t-hexylperoxy) cyclohexane (trade name “Perhexa HC” manufactured by NOF Corporation))
Curing accelerator: Methyltributylphosphonium dimethyl phosphate (trade name “Hishicolin PX-4MP” manufactured by Nippon Chemical Industry Co., Ltd.)

Comparative Example 5
27 parts by mass of the alicyclic epoxy resin [(3,4-epoxycyclohexane) methyl-3 ′, 4′-epoxycyclohexyl-carboxylate (“Celoxide 2021P” manufactured by Daicel Chemical Industries, Ltd.)], 0.027 of hydroquinone A mass part was charged in a reaction vessel, heated to 70 ° C., and hydroquinone was dissolved. Then, 11.8 parts by mass of methacrylic acid, 3-[[2- (methacryloyloxy) ethoxy] carbonyl] propionic acid (Kyoeisha Chemical Co., Ltd.) ) "Light Ester HO-MS") 16 parts by mass, charged with 1000 ppm of triphenylphosphine with respect to the solid content, and dicyclopentanyl methacrylate (manufactured by Hitachi Chemical Co., Ltd. "Fancryl FA-513M") as a solvent 2) 22.7 parts by mass were added to adjust the nonvolatile content to 70% by mass. Next, the temperature was raised to 80 ° C. and held at 90 ° C. for 7.5 hours. During this time, triphenylphosphine in an amount of 1000 ppm with respect to the solid mass was intermittently added to the reaction system. After completion of the reaction, 22.6 parts by mass of dicyclopentanyl methacrylate was added to obtain a varnish.

The varnish viscosity of the obtained varnish was 890 mPa · s.
Subsequently, 1,1-di (t-hexylperoxy) cyclohexane (“Perhexa HC” manufactured by NOF Corporation) and methyltributylphosphonium dimethyl phosphate (manufactured by Nippon Chemical Industry Co., Ltd.) as a curing catalyst were added to the obtained varnish. 1 PHR each of Hishicolin PX-4MP ") was added. Thereafter, it was poured into the gap of the mold used in Example 1 and cured at 100 ° C. for 1 hour, the cured product was taken out from the mold, further heated to 170 ° C., and kept at this temperature for 1 hour to obtain a cured product. . The obtained cured product was colored brown and the light transmittance (400 nm) was 52.2%.

Claims (9)

An epoxy resin having a cycloaliphatic structure (A), methacrylic acid (B), an acid group-containing radical polymerizable monomer (C) having an aliphatic ester bond or an aliphatic carbonate bond, a radical polymerization initiator (D), And an aliphatic cyclic structure-containing monomethacrylate compound (E) as an essential component. The acid group-containing radical polymerizable monomer (C) having an aliphatic ester bond or an aliphatic carbonate bond is represented by the following general formula (1):

(In the formula, R ¹ represents an aliphatic hydrocarbon group having 2 to 10 carbon atoms, X represents an ester bond or a carbonate bond, R ² represents an aliphatic hydrocarbon group having 2 to 10 carbon atoms, and n represents 1 to 1) Indicates an integer of 5.)
The epoxy resin composition according to claim 1, which is represented by: The epoxy resin composition according to claim 1, wherein the epoxy resin (A) is an epoxy resin having a cyclic aliphatic structure. Of a total of 100 parts by mass of an epoxy resin having a cycloaliphatic structure (A), methacrylic acid (B), and an acid group-containing radical polymerizable monomer (C) having an aliphatic ester bond or an aliphatic carbonate bond,
10 to 60 parts by mass of the epoxy resin (A),
1-35 parts by mass of the methacrylic acid (B),
The epoxy resin composition of Claim 1 which contains the acid group containing radically polymerizable monomer (C) which has the said aliphatic ester bond or an aliphatic carbonate bond in the ratio used as 5-50 mass parts. Synthetic mass of epoxy resin (A), methacrylic acid (B), acid group-containing radical polymerizable monomer (C) having aliphatic ester bond or aliphatic carbonate bond, and alicyclic structure-containing monomethacrylate compound (E) The epoxy resin composition of Claim 1 which contains the said aliphatic cyclic structure containing monomethacrylate compound (E) in the ratio used as 20-70 mass parts among 100 mass parts. An optical semiconductor sealing material comprising the epoxy resin composition according to claim 1. A cured product obtained by shaping the epoxy resin composition according to claim 1 and then curing it in a temperature range of 50 to 200 ° C. A method for producing a cured product, comprising: curing the epoxy resin composition according to claim 1 in a temperature range of 50 to 200 ° C. in a molding machine. An optical semiconductor device comprising an optical semiconductor and an electrode member bonded thereto sealed with the epoxy resin composition according to claim 1.