JP2020055973A - Thermosetting epoxy resin composition - Google Patents

Abstract

To provide a thermosetting epoxy resin composition that allows a resin composition to gelate in a shortened time, and has a shortened curing process for improved production efficiency, and can suppress volatilization of a monomer component such as an acid anhydride curing agent.SOLUTION: A thermosetting epoxy resin composition contains an alicyclic epoxy compound (A), an acid anhydride curing agent (B), a heat cation curing catalyst (C), and at least one compound selected from the group consisting of an organic acid metal salt and a metal chelate compound as a curing accelerator (D).SELECTED DRAWING: None

Description

  The present invention relates to a thermosetting epoxy resin composition, a cured product of the thermosetting epoxy resin composition, and an optical semiconductor device in which an optical semiconductor element is sealed with the cured product of the thermosetting epoxy resin composition.

  In recent years, the output of optical semiconductor devices has been increasing, and in such optical semiconductor devices, high heat resistance, light resistance, crack resistance, and the like are required for a resin (encapsulant) that covers the optical semiconductor element. ing. Conventionally, as a sealing agent for forming a sealing material having high heat resistance, light resistance, and crack resistance, for example, an alicyclic epoxy compound, monoallyl diglycidyl isocyanurate, an acid anhydride curing agent, and curing acceleration A thermosetting composition containing an agent is known (for example, see Patent Document 1). However, there is a problem that the thermosetting composition takes a long time to be cured, the production process takes a long time, and the production efficiency is reduced. In addition, there is also a problem that the monomer components such as the acid anhydride curing agent volatilize during the heat curing, and the amount is reduced from the amount of the resin initially cast.

JP 2013-209524 A

Accordingly, an object of the present invention is to reduce the gelation time of the resin composition, shorten the curing process, improve the production efficiency, and suppress the volatilization of monomer components such as an acid anhydride curing agent. An object of the present invention is to provide an epoxy resin composition.
Another object of the present invention is to provide a cured product of the thermosetting epoxy resin composition.
Another object of the present invention is to provide an optical semiconductor device in which an optical semiconductor element is sealed with a cured product of the thermosetting epoxy resin composition.

  The present inventor has conducted intensive studies to solve the above problems, and as a result, comprises an alicyclic epoxy compound, an acid anhydride curing agent, a thermal cation curing catalyst, and an organic acid metal salt and a metal chelate compound as a curing accelerator. It has been found that a thermosetting epoxy resin composition containing one or more compounds selected from the group can shorten the resin gelation time, shorten the curing process, and improve production efficiency. Further, the inventors have found that as a result of shortening the time to gelation, the amount of volatilization of a monomer component such as an acid anhydride curing agent can be suppressed, and completed the present invention.

  That is, the present invention provides a group consisting of an alicyclic epoxy compound (A), an acid anhydride curing agent (B), a thermal cationic curing catalyst (C), and a metal salt of an organic acid and a metal chelate compound as a curing accelerator. A thermosetting epoxy resin composition comprising at least one compound (D) selected from the group consisting of:

  The thermosetting epoxy resin composition preferably has a curing reaction starting temperature of 150 ° C. or lower.

  In the thermosetting epoxy resin composition, the content of the acid anhydride curing agent (B) is 0 with respect to 1 equivalent of the epoxy group in all the epoxy group-containing compounds contained in the thermosetting epoxy resin composition. The amount may be 0.01 to 1.0 equivalent.

  In the thermosetting epoxy resin composition, the alicyclic epoxy compound (A) may be a compound having a cyclohexene oxide group.

で表される化合物であってもよい。 In the thermosetting epoxy resin composition, the alicyclic epoxy compound (A) has the following formula (I-1)

The compound represented by

  The thermosetting epoxy resin composition may further contain an antioxidant (E).

［式中、Ｒ¹、Ｒ²は、同一又は異なって、水素原子又は炭素数１〜８のアルキル基を示す］
で表されるモノアリルジグリシジルイソシアヌレート化合物（Ｆ）を含んでいてもよい。 The thermosetting epoxy resin composition further has the following formula (1)

[Wherein, R ¹ and R ² are the same or different and each represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms]
And a monoallyl diglycidyl isocyanurate compound (F) represented by the formula:

  The thermosetting epoxy resin composition may further include a siloxane derivative having two or more epoxy groups in a molecule.

  The thermosetting epoxy resin composition may further include an alicyclic polyester resin.

  Further, the present invention provides a cured product of the thermosetting epoxy resin composition.

  The thermosetting epoxy resin composition may be a resin composition for encapsulating an optical semiconductor.

  The present invention also provides an optical semiconductor device in which an optical semiconductor element is encapsulated by a cured product of the resin composition for optical semiconductor encapsulation.

  Since the thermosetting epoxy resin composition of the present invention has the above constitution, the gelation time of the resin composition is shortened, the curing process is shortened, and the production efficiency is improved. Further, as a result of shortening the time to gelation, volatilization of monomer components such as an acid anhydride curing agent can be suppressed. Therefore, a cured product having high heat resistance, light resistance, and crack resistance can be efficiently formed. Therefore, by using the thermosetting epoxy resin composition of the present invention as a resin composition for encapsulating an optical semiconductor, an optical semiconductor device having high quality can be efficiently manufactured.

<Thermosetting epoxy resin composition>
The thermosetting epoxy resin composition of the present invention comprises an alicyclic epoxy compound (A), an acid anhydride curing agent (B), a thermocation curing catalyst (C), and an organic curing agent as a curing accelerator. A thermosetting resin composition comprising at least one or more compounds (D) selected from the group consisting of an acid metal salt and a metal chelate compound.

[Alicyclic epoxy compound (A)]
The alicyclic epoxy compound (A) in the thermosetting epoxy resin composition of the present invention is a compound having at least an alicyclic (aliphatic ring) structure and an epoxy group in a molecule (in one molecule). As the alicyclic epoxy compound (A), specifically, (i) a compound having an epoxy group (alicyclic epoxy group) composed of two adjacent carbon atoms and oxygen atoms constituting an alicyclic ring And (ii) a compound in which an epoxy group is directly bonded to an alicyclic ring by a single bond. However, the alicyclic epoxy compound (A) does not include a siloxane derivative having two or more epoxy groups in a molecule described below.

  As the above-mentioned (i) a compound having an epoxy group (alicyclic epoxy group) composed of two adjacent carbon atoms and oxygen atoms constituting an alicyclic ring, any one of known or commonly used compounds can be selected. Can be used. Above all, a cyclohexene oxide group is preferable as the alicyclic epoxy group.

As the above-mentioned (i) a compound having an epoxy group composed of two adjacent carbon atoms and an oxygen atom constituting an alicyclic ring, a compound having a cyclohexene oxide group is preferable from the viewpoint of transparency and heat resistance, Particularly, a compound (alicyclic epoxy compound) represented by the following formula (I) is preferable.

  In the above formula (I), X represents a single bond or a linking group (a divalent group having one or more atoms). Examples of the linking group include a divalent hydrocarbon group, a carbonyl group, an ether bond, an ester bond, a carbonate group, an amide group, and a group in which a plurality of these groups are linked.

  Examples of the alicyclic epoxy compound in which X in the above formula (I) is a single bond include (3,4,3 ′, 4′-diepoxy) bicyclohexyl.

  Examples of the divalent hydrocarbon group include a linear or branched alkylene group having 1 to 18 carbon atoms, and a divalent alicyclic hydrocarbon group. Examples of the linear or branched alkylene group having 1 to 18 carbon atoms include a methylene group, a methylmethylene group, a dimethylmethylene group, an ethylene group, a propylene group, and a trimethylene group. Examples of the divalent alicyclic hydrocarbon group include 1,2-cyclopentylene, 1,3-cyclopentylene, cyclopentylidene, 1,2-cyclohexylene, and 1,3-cyclopentylene. And a divalent cycloalkylene group (including a cycloalkylidene group) such as a cyclohexylene group, a 1,4-cyclohexylene group, and a cyclohexylidene group.

  As the above-mentioned linking group X, a linking group containing an oxygen atom is particularly preferable, and specifically, -CO-, -O-CO-O-, -COO-, -O-, -CONH-; A group in which a plurality of groups are linked; a group in which one or two or more of these groups are linked to one or two or more divalent hydrocarbon groups; Examples of the divalent hydrocarbon group include those exemplified above.

Representative examples of the alicyclic epoxy compound represented by the above formula (I) include compounds represented by the following formulas (I-1) to (I-10). Note that l and m in the following formulas (I-5) and (I-7) each represent an integer of 1 to 30. R in the following formula (I-5) is an alkylene group having 1 to 8 carbon atoms, and is a methylene group, ethylene group, propylene group, isopropylene group, butylene group, isobutylene group, s-butylene group, pentylene group, hexylene. Straight-chain or branched-chain alkylene groups such as a group, a heptylene group and an octylene group. Among these, a linear or branched alkylene group having 1 to 3 carbon atoms such as a methylene group, an ethylene group, a propylene group, and an isopropylene group is preferable. In formulas (I-9) and (I-10), n1 to n6 each represent an integer of 1 to 30.

Examples of the compound (ii) in which the epoxy group is directly bonded to the alicyclic ring by a single bond include a compound represented by the following formula (II).

In the formula (II), R ′ is a group obtained by removing p —OH from a p-valent alcohol, and p and n represent natural numbers. Examples of the p-valent alcohol [R '-(OH) _p ] include polyhydric alcohols such as 2,2-bis (hydroxymethyl) -1-butanol (alcohols having 1 to 15 carbon atoms). p is preferably 1 to 6, and n is preferably 1 to 30. When p is 2 or more, n in each group in parentheses (in parentheses) may be the same or different. Specific examples of the above compound include 1,2-epoxy-4- (2-oxiranyl) cyclohexane adduct of 2,2-bis (hydroxymethyl) -1-butanol, trade name “EHPE3150” (trade name) Daicel).

  In the thermosetting epoxy resin composition of the present invention, one type of alicyclic epoxy compound (A) may be used alone, or two or more types may be used in combination. In addition, as the alicyclic epoxy compound (A), for example, commercially available products such as “Celoxide 2021P” and “Celoxide 2081” (all manufactured by Daicel Corporation) can be used.

  Examples of the alicyclic epoxy compound (A) include 3,4-epoxycyclohexylmethyl (3,4-epoxy) cyclohexanecarboxylate represented by the above formula (I-1), trade name “CELLOXIDE 2021P” (trade name) ) From Daicel) are particularly preferred.

  Although the content (blending amount) of the alicyclic epoxy compound (A) in the thermosetting epoxy resin composition of the present invention is not particularly limited, it is 5% with respect to the thermosetting epoxy resin composition (100% by weight). It is preferably from 90 to 90% by weight, more preferably from 10 to 80% by weight, even more preferably from 15 to 70% by weight.

  The content (blending amount) of the alicyclic epoxy compound (A) with respect to the total amount of the compound having an epoxy group (all epoxy compounds) (100% by weight) contained in the thermosetting epoxy resin composition is not particularly limited, It is preferably from 10 to 95% by weight, more preferably from 20 to 90% by weight, even more preferably from 30 to 80% by weight. When the content of the alicyclic epoxy compound (A) is less than 20% by weight, heat resistance, light resistance, thermal shock resistance, and moisture absorption reflow resistance of the cured product may be reduced.

[Acid anhydride curing agent (B)]
The acid anhydride curing agent (B) in the thermosetting epoxy resin composition of the present invention is a compound having a function of curing a compound having an epoxy group. As the acid anhydride curing agent (B), a known or commonly used acid anhydride curing agent as a curing agent for an epoxy resin can be used. As the acid anhydride curing agent (B), among others, an acid anhydride which is liquid at 25 ° C. is preferable. For example, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, dodecenylsuccinic anhydride, methylendomethylenetetrahydroanhydride And phthalic acid. Also, for example, acid anhydrides that are solid at room temperature (about 25 ° C.) such as phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, and methylcyclohexenedicarboxylic anhydride are liquid at room temperature (about 25 ° C.). By dissolving in an acid anhydride of the above to form a liquid mixture, it can be preferably used as the acid anhydride curing agent (B) in the present invention. The acid anhydride curing agent (B) may be used alone or in combination of two or more. As described above, as the acid anhydride curing agent (B), from the viewpoint of heat resistance, light resistance, and crack resistance of the cured product, an anhydride of a saturated monocyclic hydrocarbon dicarboxylic acid (such as an alkyl group (Including those having a substituent bonded thereto).

  In the present invention, as the acid anhydride curing agent (B), trade names “Ricacid MH-700” (manufactured by Nippon Rika Co., Ltd.) and “Ricacid MH-700F” (manufactured by Nippon Rika Co., Ltd.) Commercial products such as "HN-5500" (trade name, manufactured by Hitachi Chemical Co., Ltd.) can also be used.

  The content (blending amount) of the acid anhydride curing agent (B) is not particularly limited, but is based on the total amount (100 parts by weight) of the epoxy group-containing compound contained in the thermosetting epoxy resin composition of the present invention. The amount is preferably 20 to 200 parts by weight, more preferably 30 to 145 parts by weight. When the content of the acid anhydride curing agent (B) is less than 20 parts by weight, the curing becomes insufficient, and the toughness of the cured product tends to decrease. On the other hand, when the content of the acid anhydride curing agent (B) exceeds 200 parts by weight, the cured product may be colored and the hue may be deteriorated.

  The content (blending amount) of the acid anhydride curing agent (B) is not particularly limited, but is based on 1 equivalent of the epoxy group in all the epoxy group-containing compounds contained in the thermosetting epoxy resin composition of the present invention. Preferably, it is used in an amount of 0.01 to 1.0 equivalent, more preferably 0.1 to 1.0 equivalent, and still more preferably 0.2 to 1.0 equivalent. When the content of the acid anhydride curing agent (B) is less than 0.01 equivalent, curing is insufficient, and the toughness of the cured product tends to decrease. On the other hand, when the content of the acid anhydride curing agent (B) exceeds 1.0 equivalent, the cured product may be colored and the hue may be deteriorated.

[Thermal cationic curing catalyst (C)]
The thermosetting epoxy resin composition of the present invention further contains a thermocationic curing catalyst (C) as an essential component. The thermal cationic curing catalyst (C) is a compound having a function of initiating and / or accelerating a curing reaction of a compound having an epoxy group by heating. When the thermosetting epoxy resin composition of the present invention contains a thermocation curing catalyst (C) together with an acid anhydride curing agent (B) and a compound (D) described below, the gelation time of the resin composition can be improved. As a result, the curing process is shortened, the production efficiency is improved, and the time to gelation is shortened. As a result, volatilization of a monomer component such as an acid anhydride curing agent can be suppressed.
The thermal cation curing catalyst (C) is not particularly limited, and examples thereof include a cationic catalyst (thermal cation polymerization initiator) that generates a cationic species by performing a heat treatment and initiates polymerization.

  Examples of the thermal cation curing catalyst that generates a cationic species by performing a heat treatment include, for example, an aryldiazonium salt, an aryliodonium salt, an arylsulfonium salt, and an allene-ion complex. Product name “CP-66”, product name “CP-77” (manufactured by ADEKA Corporation); product name “FC-509” (manufactured by 3M); product name “UVE1014” (manufactured by GE); product name “ Sun Aid SI-60L ", trade name" Sun Aid SI-80L ", trade name" Sun Aid SI-100L ", trade name" Sun Aid SI-110L ", trade name" Sun Aid SI-150L "(manufactured by Sanshin Chemical Industry Co., Ltd.) ); Commercial products such as trade name "CG-24-61" (manufactured by Ciba Japan) can be preferably used. The thermal cationic curing catalyst (C) can be used alone or in combination of two or more.

  The content (blending amount) of the thermocationic curing catalyst (C) is not particularly limited, but is 0.01 to 100 parts by weight based on the total amount (100 parts by weight) of the compound having an epoxy group contained in the thermosetting epoxy resin composition. The amount is preferably from 15 to 15 parts by weight, more preferably from 0.01 to 12 parts by weight, still more preferably from 0.05 to 10 parts by weight, particularly preferably from 0.1 to 10 parts by weight. By using the thermal cationic curing catalyst (C) within the above range, a cured product excellent in heat resistance, light resistance and transparency can be obtained. Further, the gelation time is shortened, the curing process is shortened, the production efficiency is improved, and the volatilization of monomer components such as an acid anhydride curing agent can be suppressed.

[One or more compounds (D) selected from the group consisting of metal salts of organic acids and metal chelate compounds]
The thermosetting epoxy resin composition of the present invention further comprises, as a curing accelerator, at least one compound (D) selected from the group consisting of organic acid metal salts and metal chelate compounds (hereinafter simply referred to as “compound (D) )) Is included as an essential component. The compound (D) is a compound having a function of accelerating the curing speed when the compound having an epoxy group is cured by the acid anhydride curing agent (B). The thermosetting epoxy resin composition of the present invention contains a compound (D) as a curing accelerator together with an acid anhydride curing agent (B) and a thermocationic curing catalyst (C), thereby causing gelation of the resin composition. The time is shortened, the curing process is shortened, the production efficiency is improved, and the volatilization of monomer components such as an acid anhydride curing agent can be suppressed.

  The “metal” constituting the compound (D) is not particularly limited. For example, for example, magnesium (Mg), calcium (Ca), zinc (Zn), cobalt (Co), nickel (Ni), tin (Sn) ), Barium (Ba), iron (Fe), aluminum (Al), copper (Cu), manganese (Mn), zirconium (Zr), titanium (Ti), indium (In), lead (Pb), and the like. . One of these metal atoms may be contained alone in the compound (D), or two or more thereof may be contained in combination. Among them, at least one selected from zinc, calcium, and zirconium is preferable from the viewpoint of shortening the gelation time of the resin composition. That is, the compound (D) is more preferably an organic acid zinc salt, a zinc chelate compound, an organic acid zirconium salt, a zirconium chelate compound, an organic acid calcium salt, or a calcium chelate compound.

  The organic acid constituting the metal salt of an organic acid in the compound (D) is not particularly limited, but an organic carboxylic acid is preferable. As the organic carboxylic acid, known or commonly used organic carboxylic acids can be used, and there is no particular limitation, and linear carboxylic acids having 6 to 18 carbon atoms, branched carboxylic acids, and aliphatic carboxylic acids comprising ether group-containing carboxylic acids can be used. And one or two kinds of aromatic carboxylic acids having 6 to 18 carbon atoms are preferable. Specifically, octylic acid, lauric acid, stearic acid, neodecanoic acid, oleic acid and other aliphatic carboxylic acids, benzoic acid, Aromatic carboxylic acids such as naphthylic acid are exemplified. Particularly, octylic acid and naphthylic acid are preferred from the viewpoint of shortening the gelation time of the resin composition. Compound (D) may contain one kind of the above-mentioned organic acids alone or in combination of two or more kinds.

  The organic acid metal salt can be produced by a known or commonly used method. Examples of the organic acid metal salts include “Nikka Octix Zinc”, “Naphtex Zinc” (all manufactured by Nippon Chemical Industry Co., Ltd.), “Octoop Zr”, “Octoop Ca”, “Octoop Zn” ( As described above, commercially available products such as Hope Pharmaceutical Co., Ltd.) can also be used.

As the metal chelate compound in the compound (D), known or commonly used compounds can be used. Among them, as the metal chelate compound, a metal chelate compound having β-diketone as a chelate component is preferable. Examples of the β-diketone include acetylacetone, benzoylacetone, stearoylbenzoylmethane, dibenzoylmethane, ethyl acetoacetate, dehydroacetic acid and the like. In particular, preferably a metal chelate compound having acetylacetone as a chelate component, more preferably bis (acetylacetonato) Aqua zinc (II) (bis (2,4-pentanedionato) zinc (II)) [Zn (C 5 H ₇ O ₂ ) ₂ (H ₂ O)]. The metal chelate compounds can be used alone or in combination of two or more.

  The metal chelate compound can be produced by a known or commonly used method, for example, by reacting a metal with a β-diketone and an alkali. Further, as the metal chelate compound, commercially available products such as Nasem zinc (manufactured by Nippon Chemical Industry Co., Ltd.) can be used.

  The thermosetting epoxy resin composition of the present invention can contain one type of compound (D) alone or in combination of two or more types. As the compound (D), zinc octylate, zinc naphthylate, zirconium octylate, zirconium naphthylate, calcium octylate, calcium naphthylate, bis (acetylacetonato) aquazinc (II) and the like are preferable.

  The content (blended amount) of the compound (D) is not particularly limited, but is 0.01 to 5 parts by weight based on the total amount (100 parts by weight) of the epoxy group-containing compound contained in the thermosetting epoxy resin composition. The amount is preferably from 0.05 to 5 parts by weight, more preferably from 0.1 to 5 parts by weight. When the content of the compound (D) is less than 0.01 part by weight, the gelation time of the resin composition becomes longer, and the monomer component such as an acid anhydride curing agent may be easily volatilized. On the other hand, when the content of the compound (D) exceeds 5 parts by weight, the cured product may have reduced moisture absorption reflow resistance. When the thermosetting epoxy resin composition of the present invention contains two or more compounds as the compound (D), it is preferable to control the total amount (total content) of the two in the above range.

[Antioxidant (E)]
The thermosetting epoxy resin composition of the present invention may contain an antioxidant (E). By including the antioxidant (E), it becomes possible to produce a cured product having more excellent heat resistance (particularly, yellowing resistance). As the antioxidant (E), known or commonly used antioxidants can be used, and are not particularly limited. Examples thereof include a phenolic antioxidant (a phenolic compound) and a hindered amine antioxidant (a hindered amine compound). ), Phosphorus antioxidants (phosphorous compounds), sulfur antioxidants (sulfur compounds) and the like.

  Examples of the phenolic antioxidant include 2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-butyl-p-ethylphenol, and stearyl-β- (3 Monophenols such as 2,5-di-t-butyl-4-hydroxyphenyl) propionate; 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-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy} ethyl] 2,4,8,10-tetraoxas Bisphenols such as pyro [5.5] undecane; 1,1,3-tris (2-methyl-4-hydroxy-5-t-butylphenyl) butane, 1,3,5-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 ', 5'-di-t-butyl- And high-molecular-weight phenols such as 4'-hydroxybenzyl) -s-triazine-2,4,6- (1H, 3H, 5H) trione and tocophenol.

  Examples of the hindered amine antioxidant include, for example, bis (1,2,2,6,6-pentamethyl-4-piperidyl) [[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl] methyl Butylmalonate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, methyl-1,2,2,6,6-pentamethyl-4-piperidyl sebacate, 4-benzoyloxy- 2,2,6,6-tetramethylpiperidine and the like.

  Examples of the phosphorus-based antioxidant include triphenyl phosphite, diphenyl isodecyl phosphite, phenyl diisodecyl phosphite, tris (nonylphenyl) phosphite, diisodecyl pentaerythritol phosphite, and tris (2,4-di-t-). Butylphenyl) phosphite, cyclic neopentanetetraylbis (octadecyl) phosphite, cyclic neopentanetetraylbis (2,4-di-t-butylphenyl) phosphite, cyclic neopentanetetraylbis (2 Phosphites such as 2,4-di-t-butyl-4-methylphenyl) phosphite and bis [2-t-butyl-6-methyl-4- {2- (octadecyloxycarbonyl) ethyl} phenyl] hydrogen phosphite. Fights; 9,10-di Dro-9-oxa-10-phosphaphenanthrene-10-oxide, 10- (3,5-di-tert-butyl-4-hydroxybenzyl) -9,10-dihydro-9-oxa-10-phosphaphenanthrene Oxaphosphaphenanthrene oxides such as -10-oxide and the like can be mentioned.

  Examples of the sulfur-based antioxidant include dodecanethiol, dilauryl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate, and the like. Is mentioned.

  In the thermosetting epoxy resin composition of the present invention, one kind of the antioxidant (E) can be used alone, or two or more kinds can be used in combination. In addition, the antioxidant (E) can be produced by a known or commonly used method. For example, trade names “Irganox1010” (manufactured by BASF, phenolic antioxidant), trade names “AO-60”, “ AO-80 "(Phenolic antioxidant, manufactured by ADEKA Corporation), trade name" Irgafos168 "(phosphorous antioxidant, manufactured by BASF), trade names" ADEKA STAB HP-10 "," ADEKA STAB PEP-36 "( Commercially available products such as ADEKA Corporation (phosphorous antioxidant) and trade name "HCA" (manufactured by Sanko Co., Ltd., phosphorus antioxidant) can also be used.

  When the thermosetting epoxy resin composition of the present invention contains an antioxidant (E), the content (blending amount) of the antioxidant (E) is not particularly limited. The amount is preferably from 0.1 to 5 parts by weight, more preferably from 0.5 to 3 parts by weight, based on the total amount (100 parts by weight) of the compound having an epoxy group contained. When the content of the antioxidant (E) is 0.1 part by weight or more, oxidation of the cured product is efficiently prevented, and heat resistance and yellowing resistance tend to be further improved. On the other hand, when the content of the antioxidant (E) is 5 parts by weight or less, coloring tends to be suppressed, and a cured product having a better hue tends to be easily obtained.

[Monoallyl diglycidyl isocyanurate compound (F)]
The thermosetting epoxy resin composition of the present invention may contain a monoallyl diglycidyl isocyanurate compound (F) represented by the following formula (1). The monoallyl diglycidyl isocyanurate compound (F) improves the toughness of the cured product, and particularly, the thermal shock resistance and the moisture absorption reflow resistance (especially, the crack resistance in the heat treatment in the reflow step after moisture absorption (which causes cracks). It has a role to improve the difficult properties)).

In the above formula (1), each of R ¹ and R ² (same or different) represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. Examples of the alkyl group having 1 to 8 carbon atoms include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, an s-butyl group, a pentyl group, a hexyl group, a heptyl group and an octyl group. Examples include a chain or branched alkyl group. Among them, a linear or branched alkyl group having 1 to 3 carbon atoms such as a methyl group, an ethyl group, a propyl group, and an isopropyl group is preferable. R ¹ and R ² in the above formula (1) are particularly preferably hydrogen atoms.

  Representative examples of the monoallyl diglycidyl isocyanurate compound (F) include monoallyl diglycidyl isocyanurate, 1-allyl-3,5-bis (2-methylepoxypropyl) isocyanurate, 1- (2- Methylpropenyl) -3,5-diglycidyl isocyanurate, 1- (2-methylpropenyl) -3,5-bis (2-methylepoxypropyl) isocyanurate and the like. In addition, the monoallyl diglycidyl isocyanurate compound (F) can be used alone or in combination of two or more.

  The monoallyldiglycidyl isocyanurate compound (F) may be used after being modified in advance with a compound that reacts with an epoxy group such as alcohol or acid anhydride.

  When the thermosetting epoxy resin composition of the present invention contains the monoallyl diglycidyl isocyanurate compound (F), the content (blending amount) is not particularly limited, but is included in the thermosetting epoxy resin composition. It is preferably from 5 to 60% by weight, more preferably from 8 to 55% by weight, and still more preferably from 10 to 50% by weight, based on the total amount of the compound having an epoxy group (100% by weight). When the content of the monoallyl diglycidyl isocyanurate compound (F) exceeds 60% by weight, the solubility of the monoallyl diglycidyl isocyanurate compound (F) in the thermosetting epoxy resin composition decreases, and the physical properties of the cured product May have adverse effects. On the other hand, when the content of the monoallyl diglycidyl isocyanurate compound (F) is less than 5% by weight, the cured product may have reduced thermal shock resistance and moisture absorption reflow resistance.

  When the thermosetting epoxy resin composition of the present invention contains the monoallyl diglycidyl isocyanurate compound (F), the total amount of the alicyclic epoxy compound (A) and the monoallyl diglycidyl isocyanurate compound (F) The content (blending amount) of the monoallyl diglycidyl isocyanurate compound (F) with respect to (100% by weight) is not particularly limited, but is preferably 5 to 60% by weight, more preferably 8 to 55% by weight, and still more preferably. 10 to 50% by weight. When the content of the monoallyl diglycidyl isocyanurate compound (F) exceeds 60% by weight, the solubility of the monoallyl diglycidyl isocyanurate compound (F) in the thermosetting epoxy resin composition decreases, and the physical properties of the cured product May have adverse effects. On the other hand, when the content of the monoallyl diglycidyl isocyanurate compound (F) is less than 5% by weight, the cured product may have reduced thermal shock resistance and moisture absorption reflow resistance.

[Alicyclic polyester resin]
The thermosetting epoxy resin composition of the present invention preferably further contains an alicyclic polyester resin. By containing the alicyclic polyester resin, in particular, the heat resistance and light resistance of the cured product tend to be improved, and the decrease in luminous intensity of the optical semiconductor device tends to be further suppressed. The alicyclic polyester resin is a polyester resin having at least an alicyclic structure (aliphatic ring structure). In particular, from the viewpoint of improving the heat resistance and light resistance of the cured product, the alicyclic polyester resin is preferably an alicyclic polyester resin having an alicyclic ring (alicyclic structure) in the main chain.

  The alicyclic structure in the alicyclic polyester resin is not particularly limited, and examples thereof include a monocyclic hydrocarbon structure and a bridged cyclic hydrocarbon structure (for example, a bicyclic hydrocarbon). Among them, a saturated monocyclic hydrocarbon structure or a saturated bridged ring hydrocarbon structure in which the alicyclic skeleton (carbon-carbon bond) is entirely constituted by a carbon-carbon single bond is particularly preferable. Further, the alicyclic structure in the alicyclic polyester resin may be introduced into only one of the structural unit derived from dicarboxylic acid and the structural unit derived from diol, or both may be introduced, particularly Not limited.

  The alicyclic polyester resin has a structural unit derived from a monomer component having an alicyclic structure. Examples of the monomer having an alicyclic structure include diols and dicarboxylic acids having a known or commonly used alicyclic structure, and are not particularly limited. For example, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 4-methyl-1,2-cyclohexanedicarboxylic acid, hymic acid, 1,4-decahydronaphthalenedicarboxylic acid, 1,5-decahydronaphthalenedicarboxylic acid, 2,6-decahydronaphthalene Dicarboxylic acids having an alicyclic structure (including derivatives such as acid anhydrides) such as dicarboxylic acids and 2,7-decahydronaphthalenedicarboxylic acid; 1,2-cyclopentanediol, 1,3-cyclopentanediol, 1,2-cyclopentanedimethanol, 1,3-cyclopentanedimethanol 5-membered ring diol such as bis (hydroxymethyl) tricyclo [5.2.1.0] decane, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,2-cyclohexanedi 6-membered ring diols such as methanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 2,2-bis- (4-hydroxycyclohexyl) propane, and diols having an alicyclic structure such as hydrogenated bisphenol A (Including their derivatives).

  The alicyclic polyester resin may have a structural unit derived from a monomer component having no alicyclic structure. Examples of the monomer having no alicyclic structure include aromatic dicarboxylic acids (including derivatives such as acid anhydrides) such as terephthalic acid, isophthalic acid, phthalic acid, and naphthalenedicarboxylic acid; adipic acid, sebacic acid, and azelaic acid , Succinic acid, fumaric acid, maleic acid and other aliphatic dicarboxylic acids (including derivatives such as acid anhydrides); ethylene glycol, propylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3- Butanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, 3-methylpentanediol, diethylene glycol, 3-methyl-1,5-pentanediol, 2-methyl -1,3-propanediol, 2,2-diethyl-1,3-propanediol 2-butyl-2-ethyl-1,3-propanediol, xylylene glycol, ethylene oxide adduct of bisphenol A, diols such as propylene oxide adduct of bisphenol A (including derivatives thereof) and the like. In addition, monomers in which an appropriate substituent (for example, an alkyl group, an alkoxy group, a halogen atom, or the like) is bonded to the dicarboxylic acid or diol having no alicyclic structure are also included in the monomers having no alicyclic structure.

  The ratio of the monomer unit having an alicyclic ring to all monomer units (all monomer components) (100 mol%) constituting the alicyclic polyester resin is not particularly limited, but is 10 mol% or more (for example, 10 to 80 mol%). ) Is preferable, more preferably 25 to 70 mol%, and still more preferably 40 to 60 mol%. If the proportion of the monomer unit having an alicyclic ring is less than 10 mol%, the heat resistance, light resistance, thermal shock resistance, and moisture absorption reflow resistance of the cured product may decrease.

  As the alicyclic polyester resin, an alicyclic polyester resin containing at least one or more structural units represented by the following formulas (2) to (4) is particularly preferable.

［式中、Ｒ³は直鎖、分岐鎖、又は環状の炭素数２〜１５のアルキレン基を表す。また、Ｒ⁴〜Ｒ⁷は、それぞれ独立に、水素原子又は直鎖若しくは分岐鎖状の炭素数１〜４のアルキル基を表し、Ｒ⁴〜Ｒ⁷から選ばれる二つが結合して環を形成していてもよい。］

[In the formula, R ³ represents a linear, branched, or cyclic alkylene group having 2 to 15 carbon atoms. R ^{4 to} R ⁷ each independently represent a hydrogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms, and two selected from R ^{4 to} R ⁷ are bonded to form a ring; It may be. ]

［式中、Ｒ³は直鎖、分岐鎖、又は環状の炭素数２〜１５のアルキレン基を表す。また、Ｒ⁴〜Ｒ⁷は、それぞれ独立に、水素原子又は直鎖若しくは分岐鎖状の炭素数１〜４のアルキル基を表し、Ｒ⁴〜Ｒ⁷から選ばれる二つが結合して環を形成していてもよい。］

[In the formula, R ³ represents a linear, branched, or cyclic alkylene group having 2 to 15 carbon atoms. R ^{4 to} R ⁷ each independently represent a hydrogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms, and two selected from R ^{4 to} R ⁷ are bonded to form a ring; It may be. ]

［式中、Ｒ³は直鎖、分岐鎖、又は環状の炭素数２〜１５のアルキレン基を表す。また、Ｒ⁴〜Ｒ⁷は、それぞれ独立に、水素原子又は直鎖若しくは分岐鎖状の炭素数１〜４のアルキル基を表し、Ｒ⁴〜Ｒ⁷から選ばれる二つが結合して環を形成していてもよい。］

[In the formula, R ³ represents a linear, branched, or cyclic alkylene group having 2 to 15 carbon atoms. R ^{4 to} R ⁷ each independently represent a hydrogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms, and two selected from R ^{4 to} R ⁷ are bonded to form a ring; It may be. ]

Preferable specific examples of the constitutional units represented by the above formulas (2) to (4) include, for example, constitutions derived from 4-methyl-1,2-cyclohexanedicarboxylic acid and ethylene glycol represented by the following formula (5). Units. The alicyclic polyester resin having the constituent unit is obtained, for example, by polycondensing methylhexahydrophthalic anhydride and ethylene glycol.

Other preferable specific examples of the structural units represented by the above formulas (2) to (4) include, for example, 1,4-cyclohexanedicarboxylic acid represented by the following formula (6) and neopentyl glycol-derived Structural units are included. The alicyclic polyester resin having the structural unit is obtained, for example, by polycondensing 1,4-cyclohexanedicarboxylic acid with neopentyl glycol.

  When the alicyclic polyester resin has the structural units represented by the formulas (2) to (4), the total amount of the contents of the structural units (total content; all monomer units constituting the structural units) Is not particularly limited, but 20 mol% or more (for example, 20 to 100 mol%) with respect to all constituent units (100 mol%; all monomer units constituting the alicyclic polyester resin) of the alicyclic polyester resin. Preferably, it is 50 to 100 mol%, more preferably 80 to 100 mol%. When the content of the structural units represented by the above formulas (2) to (4) is less than 20 mol%, heat resistance, light resistance, thermal shock resistance, and moisture absorption reflow resistance of the cured product may be reduced. .

  The number average molecular weight of the alicyclic polyester resin is not particularly limited, but is preferably 300 to 100,000, and more preferably 300 to 30,000. When the number average molecular weight of the alicyclic polyester resin is less than 300, the toughness of the cured product is not sufficient, and the thermal shock resistance and the moisture absorption reflow resistance may decrease. On the other hand, when the number average molecular weight of the alicyclic polyester resin exceeds 100,000, the compatibility with the curing agent (D) decreases, and the transparency of the cured product may decrease. The number average molecular weight of the alicyclic polyester resin can be measured, for example, as a value in terms of standard polystyrene by GPC (gel permeation chromatography).

  In addition, the said alicyclic polyester resin can be used individually by 1 type or in combination of 2 or more types.

  The alicyclic polyester resin is not particularly limited, and can be produced by a known or commonly used method. More specifically, for example, the alicyclic polyester resin may be obtained by polycondensation of the above-mentioned dicarboxylic acid and diol by a conventional method, or a derivative of the above-mentioned dicarboxylic acid (an acid anhydride, an ester, an acid). Halogenated compound) and a diol by a conventional method.

  In the thermosetting epoxy resin composition of the present invention, the content (blending amount) of the alicyclic polyester resin is not particularly limited, but when the curable resin composition contains a curing agent (D), The amount is preferably 1 to 60% by weight, more preferably 5 to 30% by weight, based on the total amount (100% by weight) of the formula polyester resin and the curing agent (D). If the content of the alicyclic polyester resin is less than 1% by weight, the cured product may have insufficient heat shock resistance and moisture absorption reflow resistance. On the other hand, when the content of the alicyclic polyester resin exceeds 60% by weight, the transparency and heat resistance of the cured product may be reduced.

  The content (blending amount) of the alicyclic polyester resin with respect to the total amount (100 parts by weight) of the compound having an epoxy group contained in the present thermosetting epoxy resin composition is not particularly limited, but is 5 to 50% by weight. Parts by weight, more preferably 10 to 45 parts by weight, even more preferably 15 to 40 parts by weight. If the content of the alicyclic polyester resin is less than 5 parts by weight, the heat resistance, light resistance, heat shock resistance, and moisture absorption reflow resistance of the cured product may be insufficient. On the other hand, if the content of the alicyclic polyester resin exceeds 50 parts by weight, the cured product may have reduced thermal shock resistance and moisture absorption reflow resistance.

[Siloxane derivative having two or more epoxy groups in the molecule]
The thermosetting epoxy resin composition of the present invention preferably further contains a siloxane derivative having two or more epoxy groups in a molecule (in one molecule). By including a siloxane derivative having two or more epoxy groups in the molecule, the heat resistance and light resistance of the cured product can be particularly improved to higher levels.

  The siloxane skeleton (Si—O—Si skeleton) in the siloxane derivative having two or more epoxy groups in the molecule is not particularly limited, but is, for example, a cyclic siloxane skeleton; a linear silicone, a cage type, or a ladder type. And a polysiloxane skeleton such as polysilsesquioxane. Above all, as the siloxane skeleton, a cyclic siloxane skeleton and a linear silicone skeleton are preferable from the viewpoint of improving the heat resistance and light resistance of the cured product and suppressing a decrease in luminous intensity. That is, as the siloxane derivative having two or more epoxy groups in a molecule, a cyclic siloxane having two or more epoxy groups in a molecule and a linear silicone having two or more epoxy groups in a molecule are preferable. The siloxane derivative having two or more epoxy groups in the molecule can be used alone or in combination of two or more.

  When the siloxane derivative having two or more epoxy groups in the molecule is a cyclic siloxane having two or more epoxy groups, the number of Si—O units forming a siloxane ring (to the number of silicon atoms forming a siloxane ring, Is not particularly limited, but is preferably 2 to 12, more preferably 4 to 8, from the viewpoint of improving the heat resistance and light resistance of the cured product.

  The weight average molecular weight of the siloxane derivative having two or more epoxy groups in the molecule is not particularly limited, but is preferably from 100 to 3,000, and more preferably from 180 to 2,000, from the viewpoint of improving the heat resistance and light resistance of the cured product. It is.

  The number of epoxy groups in one molecule of the siloxane derivative having two or more epoxy groups in the molecule is not particularly limited as long as it is two or more, but from the viewpoint of improving heat resistance and light resistance of the cured product, the number is preferably 2 or more. ４4 (2, 3, or 4) are preferred.

  The epoxy equivalent (according to JIS K7236) of the siloxane derivative having two or more epoxy groups in the molecule is not particularly limited, but is preferably 180 to 400 from the viewpoint of improving the heat resistance and light resistance of the cured product. Preferably it is 240-400, More preferably, it is 240-350.

  The epoxy group in the siloxane derivative having two or more epoxy groups in the molecule is not particularly limited. However, from the viewpoint of improving the heat resistance and light resistance of the cured product, two epoxy groups forming an aliphatic ring may be used. An epoxy group (alicyclic epoxy group) composed of an oxygen atom is preferred, and a cyclohexene oxide group is particularly preferred.

As the siloxane derivative having two or more epoxy groups in the molecule, specifically, for example, 2,4-di [2- (3- {oxabicyclo [4.1.0] heptyl}) ethyl]- 2,4,6,6,8,8-hexamethyl-cyclotetrasiloxane, 4,8-di [2- (3- {oxabicyclo [4.1.0] heptyl}) ethyl] -2,2,4 , 6,6,8-Hexamethyl-cyclotetrasiloxane, 2,4-di [2- (3- {oxabicyclo [4.1.0] heptyl}) ethyl] -6,8-dipropyl-2,4 6,8-tetramethyl-cyclotetrasiloxane, 4,8-di [2- (3- {oxabicyclo [4.1.0] heptyl}) ethyl] -2,6-dipropyl-2,4,6 8-tetramethyl-cyclotetrasiloxane, 2,4,8- [2- (3- {oxabicyclo [4.1.0] heptyl}) ethyl] -2,4,6,6,8-pentamethyl-cyclotetrasiloxane, 2,4,8-tri [2- (3 -{Oxabicyclo [4.1.0] heptyl}) ethyl] -6-propyl-2,4,6,8-tetramethyl-cyclotetrasiloxane, 2,4,6,8-tetra [2- (3 -{Oxabicyclo [4.1.0] heptyl}) ethyl] -2,4,6,8-tetramethyl-cyclotetrasiloxane, silsesquioxane having two or more epoxy groups in a molecule, and the like. . More specifically, for example, a cyclic siloxane having two or more epoxy groups in a molecule represented by the following formula is exemplified.

  Examples of the siloxane derivative having two or more epoxy groups in the molecule include, for example, an alicyclic epoxy group-containing silicone resin described in JP-A-2008-248169 and one described in JP-A-2008-19422. Organopolysilsesquioxane resins having at least two epoxy functional groups in the molecule can also be used.

  Examples of the siloxane derivative having two or more epoxy groups in the molecule include “X-40-2678” (trade name) which is a cyclic siloxane having two or more epoxy groups in the molecule (manufactured by Shin-Etsu Chemical Co., Ltd.). Commercial products such as "X-40-2670" (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.) and "X-40-2720" (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.) can also be used.

  The content (blending amount) of the siloxane derivative having two or more epoxy groups in the molecule is not particularly limited, but is based on the total amount (100% by weight) of the epoxy group-containing compound contained in the thermosetting epoxy resin composition. On the other hand, it is preferably 5 to 60% by weight, more preferably 8 to 55% by weight, further preferably 10 to 50% by weight, and particularly preferably 15 to 40% by weight. If the content of the siloxane derivative having two or more epoxy groups in the molecule is less than 5% by weight, the heat resistance and light resistance of the cured product may be insufficient. On the other hand, when the content of the siloxane derivative having two or more epoxy groups in the molecule exceeds 60% by weight, the heat shock resistance and the moisture absorption reflow resistance of the cured product may decrease.

  The content (blending amount) of the siloxane derivative having two or more epoxy groups in the molecule with respect to 100 parts by weight of the alicyclic epoxy compound (A) is not particularly limited, but is preferably 10 to 200 parts by weight. It is preferably 20 to 180 parts by weight, more preferably 30 to 150 parts by weight, particularly preferably 35 to 145 parts by weight. When the content of the siloxane derivative having two or more epoxy groups in the molecule is less than 10 parts by weight, the heat resistance, light resistance, thermal shock resistance, and moisture absorption reflow resistance of the cured product may be insufficient. On the other hand, when the content of the siloxane derivative having two or more epoxy groups in the molecule exceeds 200 parts by weight, the thermal shock resistance and the moisture absorption reflow resistance of the cured product may be reduced.

[Rubber particles]
The thermosetting epoxy resin composition of the present invention may further contain rubber particles. Examples of the rubber particles include rubber particles such as particulate NBR (acrylonitrile-butadiene rubber), reactive terminal carboxyl group NBR (CTBN), metal-free NBR, and particulate SBR (styrene-butadiene rubber). As the rubber particles, rubber particles having a multilayer structure (core-shell structure) composed of a core portion having rubber elasticity and at least one shell layer covering the core portion are preferable. The rubber particles are composed of a polymer (polymer) containing (meth) acrylate as an essential monomer component, and react with a compound having an epoxy group such as an alicyclic epoxy compound (A) on the surface. Rubber particles having a hydroxyl group and / or a carboxyl group (one or both of a hydroxyl group and a carboxyl group) as a functional group to be obtained are preferable. When the hydroxyl group and / or the carboxyl group do not exist on the surface of the rubber particles, the cured product becomes cloudy due to a thermal shock such as a cooling / heating cycle and the transparency is undesirably reduced.

  The polymer constituting the core portion having rubber elasticity in the rubber particles is not particularly limited, but may be a (meth) acrylate such as methyl (meth) acrylate, ethyl (meth) acrylate, or butyl (meth) acrylate. It is preferable to use an essential monomer component. The polymer constituting the core portion having the rubber elasticity includes, for example, styrene, aromatic vinyl such as α-methylstyrene, acrylonitrile, nitrile such as methacrylonitrile, butadiene, conjugated diene such as isoprene, ethylene, propylene, and the like. Isobutene or the like may be contained as a monomer component.

  Among them, the polymer constituting the core portion having rubber elasticity includes, as a monomer component, one or two or more selected from the group consisting of aromatic vinyl, nitrile, and conjugated diene, together with (meth) acrylate. It is preferable to include them in combination. That is, examples of the polymer constituting the core portion include binary copolymers such as (meth) acrylate / aromatic vinyl, (meth) acrylate / conjugated diene; and (meth) acrylate / aromatic. And ternary copolymers such as aromatic vinyl / conjugated dienes. The polymer constituting the core portion may include silicone such as polydimethylsiloxane and polyphenylmethylsiloxane, polyurethane, and the like.

  The polymer constituting the core portion includes, as other monomer components, divinylbenzene, allyl (meth) acrylate, ethylene glycol di (meth) acrylate, diallyl maleate, triallyl cyanurate, diallyl phthalate, butylene glycol diacrylate, and the like. One monomer (one molecule) may contain a reactive crosslinking monomer having two or more reactive functional groups.

  The core portion of the rubber particles may be a core portion composed of a (meth) acrylate / aromatic vinyl binary copolymer (particularly, butyl acrylate / styrene). This is preferable because the rate can be easily adjusted.

  The core portion of the rubber particles can be produced by a commonly used method, for example, by a method of polymerizing the monomer by an emulsion polymerization method. In the emulsion polymerization method, the entire amount of the monomer may be charged at a time and polymerized, or after a part of the monomer is polymerized, the remainder may be continuously or intermittently added and polymerized. Further, a polymerization method using seed particles may be used.

  The polymer forming the shell layer of the rubber particles is preferably a polymer different from the polymer forming the core portion. As described above, the shell layer preferably has a hydroxyl group and / or a carboxyl group as a functional group capable of reacting with a compound having an epoxy group such as the alicyclic epoxy compound (A). Thereby, the adhesiveness can be improved particularly at the interface with the alicyclic epoxy compound (A), and the cured product obtained by curing the thermosetting epoxy resin composition containing the rubber particles having the shell layer can be obtained. Thus, excellent crack resistance can be exhibited. In addition, it is possible to prevent a decrease in the glass transition temperature of the cured product.

  The polymer constituting the shell layer preferably contains a (meth) acrylate such as methyl (meth) acrylate, ethyl (meth) acrylate, and butyl (meth) acrylate as an essential monomer component. For example, when butyl acrylate is used as the (meth) acrylate in the core portion, a (meth) acrylate other than butyl acrylate (for example, (meth) acryl) is used as a monomer component of the polymer constituting the shell layer. It is preferable to use methyl acrylate, ethyl (meth) acrylate, butyl methacrylate, and the like. Examples of the monomer component that may be contained in addition to the (meth) acrylic acid ester include, for example, aromatic vinyl such as styrene and α-methylstyrene, and nitrile such as acrylonitrile and methacrylonitrile. In the rubber particles, as the monomer component constituting the shell layer, it is preferable that the monomer be used alone or in combination of two or more, together with the (meth) acrylic acid ester. However, it is preferable because the refractive index of the rubber particles can be easily adjusted.

  Further, the polymer constituting the shell layer is used as a monomer component to form a hydroxyl group and / or a carboxyl group as a functional group capable of reacting with a compound having an epoxy group such as the alicyclic epoxy compound (A). A hydroxyl group-containing monomer (e.g., hydroxyalkyl (meth) acrylate such as 2-hydroxyethyl (meth) acrylate), and a carboxyl group-containing monomer (e.g., α, β-unsaturated acid such as (meth) acrylic acid, Α, β-unsaturated acid anhydrides such as maleic anhydride).

  The polymer constituting the shell layer in the rubber particles preferably contains, as a monomer component, one or more selected from the above monomers in combination with the (meth) acrylate. That is, the above-mentioned shell layer is made of a ternary material such as (meth) acrylate / aromatic vinyl / hydroxyalkyl (meth) acrylate, (meth) acrylate / aromatic vinyl / α, β-unsaturated acid. The shell layer is preferably made of a polymer or the like.

  Further, the polymer constituting the shell layer includes, as the other monomer components, divinylbenzene, allyl (meth) acrylate, ethylene glycol di (meth) acrylate, diallyl maleate, One monomer (one molecule) such as allyl cyanurate, diallyl phthalate and butylene glycol diacrylate may contain a reactive crosslinking monomer having two or more reactive functional groups.

  The rubber particles (rubber particles having a core-shell structure) are obtained by covering the core portion with a shell layer. Examples of the method of coating the core portion with a shell layer include, for example, a method of coating the surface of a rubber elastic core portion obtained by the above method by applying a copolymer constituting a shell layer to the surface, A method in which a core portion having rubber elasticity obtained by the above is used as a trunk component, and each component constituting the shell layer is used as a branch component to carry out graft polymerization.

  The average particle size of the rubber particles is not particularly limited, but is preferably from 10 to 500 nm, more preferably from 20 to 400 nm. The maximum particle size of the rubber particles is not particularly limited, but is preferably from 50 to 1000 nm, and more preferably from 100 to 800 nm. When the average particle size exceeds 500 nm or when the maximum particle size exceeds 1000 nm, the dispersibility of the rubber particles in the cured product may decrease, and the crack resistance may decrease. On the other hand, if the average particle diameter is less than 10 nm, or if the maximum particle diameter is less than 50 nm, the effect of improving the crack resistance of the cured product may be difficult to obtain.

  The refractive index of the rubber particles is not particularly limited, but is preferably from 1.40 to 1.60, and more preferably from 1.42 to 1.58. The difference between the refractive index of the rubber particles and the refractive index of the cured product obtained by curing the thermosetting epoxy resin composition containing the rubber particles (the thermosetting epoxy resin composition of the present invention) is ± 0. It is preferably within 0.03. When the difference in the refractive index is more than ± 0.03, the transparency of the cured product is reduced and sometimes becomes cloudy, and the luminous intensity of the optical semiconductor device tends to decrease, and the function of the optical semiconductor device is lost. There is.

  The refractive index of the rubber particles is, for example, 1 g of the rubber particles is cast into a mold and compression molded at 210 ° C. and 4 MPa to obtain a flat plate having a thickness of 1 mm. From the obtained flat plate, a test piece of 20 mm long × 6 mm wide is obtained. And using a multi-wavelength Abbe refractometer (trade name "DR-M2", manufactured by Atago Co., Ltd.) with the prism and the test piece in close contact with each other using monobromonaphthalene as an intermediate solution, It can be determined by measuring the refractive index at 20 ° C. and the sodium D line.

  The refractive index of the cured product of the thermosetting epoxy resin composition of the present invention is, for example, from the cured product obtained by the heat curing method described in the section of the optical semiconductor device below, 20 mm length × 6 mm width × 1 mm thickness. A test piece was cut out and a multi-wavelength Abbe refractometer (trade name "DR-M2", manufactured by Atago Co., Ltd.) was used with the prism and the test piece in close contact with each other using monobromonaphthalene as an intermediate liquid. It can be determined by measuring the refractive index at 20 ° C. and the sodium D line.

  The content (blending amount) of the rubber particles in the thermosetting epoxy resin composition of the present invention is not particularly limited, but the total amount (100 parts by weight) of the compound having an epoxy group contained in the thermosetting epoxy resin composition is not limited. ), The amount is preferably 0.5 to 30 parts by weight, more preferably 1 to 20 parts by weight. When the content of the rubber particles is less than 0.5 part by weight, the crack resistance of the cured product tends to decrease. On the other hand, when the content of the rubber particles exceeds 30 parts by weight, the heat resistance of the cured product tends to decrease.

[Additive]
In addition to the above, the thermosetting epoxy resin composition of the present invention may contain various additives within a range that does not impair the effects of the present invention. When a compound having a hydroxyl group such as ethylene glycol, diethylene glycol, propylene glycol, or glycerin is contained as the additive, the reaction can proceed slowly. In addition, as long as the viscosity and transparency are not impaired, a cationic photocuring catalyst, a silicone-based or fluorine-based antifoaming agent, a leveling agent, γ-glycidoxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, etc. Use conventional additives such as silane coupling agents, surfactants, inorganic fillers such as silica and alumina, flame retardants, colorants, ultraviolet absorbers, ion adsorbents, pigments, phosphors, mold release agents, etc. be able to.

<Production method of thermosetting epoxy resin composition>
The thermosetting epoxy resin composition of the present invention comprises at least the alicyclic epoxy compound (A), the acid anhydride curing agent (B), the thermocationic curing catalyst (C), and the compound (D). The production method (preparation method) is not particularly limited. Specifically, for example, it can be prepared by stirring and mixing the respective components at a predetermined ratio, and degassing under vacuum if necessary. Alternatively, an epoxy such as an alicyclic epoxy compound (A) can be used. A composition containing a compound having a group as an essential component (sometimes referred to as an “epoxy resin”), an acid anhydride curing agent (B), a thermal cation curing catalyst (C), and a compound (D) as essential components And a composition containing the same (which may be referred to as an “epoxy curing agent”) is separately prepared, and the epoxy resin and the epoxy curing agent are stirred and mixed at a predetermined ratio, and if necessary, defoamed under vacuum. Can also be prepared.

  The temperature at the time of stirring and mixing when preparing the epoxy resin is not particularly limited, but is preferably 30 to 150 ° C, more preferably 35 to 130 ° C. The temperature during stirring and mixing when preparing the epoxy curing agent is not particularly limited, but is preferably 30 to 100 ° C, more preferably 35 to 80 ° C. For the stirring and mixing, a known device, for example, a rotation and revolution type mixer, a planetary mixer, a kneader, a dissolver and the like can be used.

  In particular, when the thermosetting epoxy resin composition of the present invention contains the alicyclic polyester resin as an essential component, from the viewpoint of obtaining a more uniform composition, the alicyclic polyester resin and the acid anhydride curing agent are used. (B) was previously mixed to obtain a mixture thereof (a mixture of an alicyclic polyester resin and an acid anhydride curing agent (B)), and then the mixture was added to the thermal cation curing catalyst (C) and the compound (D). It is preferable to prepare an epoxy curing agent by blending with other additives, and then to mix the epoxy curing agent with an epoxy resin separately prepared. The temperature at which the alicyclic polyester resin and the acid anhydride curing agent (B) are mixed is not particularly limited, but is preferably from 60 to 130 ° C, more preferably from 90 to 120 ° C. The mixing time is not particularly limited, but is preferably 30 to 100 minutes, and more preferably 45 to 80 minutes. The mixing is not particularly limited, but is preferably performed in a nitrogen atmosphere. In addition, the above-mentioned known device can be used for mixing.

  After mixing the alicyclic polyester resin and the acid anhydride curing agent (B), the mixture is not particularly limited, but is further subjected to appropriate chemical treatment (for example, hydrogenation or terminal modification of the alicyclic polyester resin). You may. In the mixture of the alicyclic polyester resin and the acid anhydride curing agent (B), a part of the acid anhydride curing agent (B) is replaced with the alicyclic polyester resin (for example, a hydroxyl group of the alicyclic polyester resin). Etc.).

  Examples of the mixture of the alicyclic polyester resin and the acid anhydride curing agent (B) include “HN-7200” (trade name, manufactured by Hitachi Chemical Co., Ltd.) and “HN-5700” (trade name, manufactured by Hitachi Chemical Co., Ltd.). Commercial products such as those manufactured by Kogyo Co., Ltd.) can also be used.

  The thermosetting epoxy resin composition of the present invention comprises an alicyclic epoxy compound (A), an acid anhydride curing agent (B), a thermocation curing catalyst (C), and a compound (D) as essential components. Therefore, the curing reaction initiation temperature is low, the gelation time is shortened, the curing process is shortened, and the production efficiency is improved.

  The curing reaction initiation temperature of the thermosetting epoxy resin composition of the present invention is preferably 150 ° C. or lower, more preferably 130 ° C. or lower, and further preferably 120 ° C. or lower. The curing reaction start temperature is a temperature at which an exothermic peak of the curing reaction first appears in a measurement using a differential scanning calorimeter.

  The gel time (second) of the thermosetting epoxy resin composition of the present invention is preferably 1050 seconds or less, more preferably 950 seconds or less, and even more preferably 850 seconds or less. The gel time is a time (second) measured for the thermosetting epoxy resin composition in a test example described later.

<Cured product>
By curing the thermosetting epoxy resin composition of the present invention, a cured product excellent in heat resistance, light resistance, and thermal shock resistance, and particularly excellent in moisture absorption reflow resistance can be obtained. The heating temperature (curing temperature) at the time of curing is not particularly limited, but is preferably 45 to 200 ° C, more preferably 100 to 190 ° C, and still more preferably 100 to 180 ° C. The time for heating (curing time) during curing is not particularly limited, but is preferably 30 to 600 minutes, more preferably 45 to 540 minutes, and further preferably 60 to 480 minutes. Since the thermosetting epoxy resin composition of the present invention has the above-described configuration, the curing reaction can efficiently proceed with a low curing temperature and a short curing time, but the curing temperature and the curing time are the lower limit of the above range. If it is lower than the upper limit of the above range, the curing will be insufficient. Conversely, if it is higher than the upper limit of the above range, the decomposition of the resin component and the volatilization of the monomer component such as the acid anhydride curing agent (B) may occur. Absent. The curing conditions depend on various conditions. For example, when the curing temperature is increased, the curing time is shortened, and when the curing temperature is decreased, the curing time can be appropriately adjusted by increasing the curing time.

<Resin composition for optical semiconductor encapsulation>
The thermosetting epoxy resin composition of the present invention can be preferably used as a resin composition for encapsulating an optical semiconductor. An optical semiconductor having an optical semiconductor element encapsulated by a cured product having high heat resistance, light resistance, and thermal shock resistance, and particularly excellent in moisture absorption and reflow resistance, when used as the resin composition for optical semiconductor encapsulation. A device is obtained. The optical semiconductor device has a high output and a high luminance even when the optical semiconductor device is provided, and the luminous intensity hardly decreases over time, especially when the optical semiconductor device is heated in a reflow process after being stored under high humidity conditions. However, deterioration such as a decrease in luminous intensity does not easily occur.

<Optical semiconductor device>
The optical semiconductor device of the present invention is an optical semiconductor device in which an optical semiconductor element is encapsulated with a cured product of the thermosetting epoxy resin composition (optical semiconductor encapsulating resin composition) of the present invention. The encapsulation of the optical semiconductor element is performed by injecting the thermosetting epoxy resin composition prepared by the above-described method into a predetermined mold and heating and curing under a predetermined condition. As a result, an optical semiconductor device in which the optical semiconductor element is sealed with the cured product of the thermosetting epoxy resin composition is obtained. The curing temperature and the curing time can be set in the same range as in the preparation of the cured product, and the optical semiconductor device can be manufactured efficiently with a short curing time. In addition, since a reduction in the amount of resin due to volatilization of a monomer component such as the acid anhydride curing agent (B) is suppressed, a high-quality optical semiconductor device can be manufactured.

  The thermosetting epoxy resin composition of the present invention has a short curing time and can efficiently form a cured product, and thus is not limited to the above-mentioned optical semiconductor element encapsulation application, and includes, for example, an adhesive, an electric insulating material, Laminates, coatings, inks, paints, sealants, resists, composite materials, transparent substrates, transparent sheets, transparent films, optical elements, optical lenses, optical members, stereolithography, electronic paper, touch panels, solar cell substrates, optical waveguides, It can also be suitably used for applications such as light guide plates and holographic memories.

  Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples. In addition, the compounding quantity of the "organic acid metal salt" in the following Table 1 is an amount containing a solvent component.

Examples 1 to 9, Comparative Examples 1 to 7
An alicyclic epoxy compound, other epoxy compounds, and an antioxidant were mixed according to the formulation (unit: parts by weight) shown in Tables 1 and 2, and the mixture was stirred at 80 ° C. for 1 hour. Next, the epoxy mixture, the acid anhydride curing agent (including the alicyclic ester resin), the organic acid metal salt, and the thermal cation curing catalyst were mixed so that the mixing ratios shown in Tables 1 and 2 were obtained. To obtain a thermosetting epoxy resin composition.

  1.5 g of the above thermosetting epoxy resin composition mixed with a Pyrex (registered trademark) glass test tube (without rim, outer diameter 12 mm × 90 mm, manufactured by AGC Techno Glass Co., Ltd.) was weighed, and a glass rod was inserted. The gel time at 120 ° C. was measured using a trade name “No. 153 Gel Time Tester” (manufactured by Yasuda Seiki Seisakusho KK). The results are shown in "Gel time [s]" in Table 1.

  The mold was filled with the thermosetting epoxy resin compositions obtained in Examples and Comparative Examples, and heated in an oven at 120 ° C. (resin curing oven) for 5 hours to obtain a cured product having a thickness of 3 mm. The light transmittance (thickness direction) of light having a wavelength of 450 nm of the obtained cured product was measured using a spectrophotometer (trade name “UV-2400”, manufactured by Shimadzu Corporation). After aging this cured product in an oven at 120 ° C. for 1000 hours, the light transmittance (thickness direction) of light having a wavelength of 450 nm was measured again. The change was calculated by subtracting the transmittance after aging from the transmittance before aging. The results are shown in Table 1 “Transmissivity decrease [%] due to aging”.

(Judgment)
From the results of the gel time measurement and the decrease in transmittance due to aging, the following judgment was made.
・ ・ ・: Gel time is 850 seconds or less, and transmittance decrease due to aging is 10% or less.
×: Other than the above.

The components used in Examples and Comparative Examples are as follows.
<Alicyclic epoxy resin (A)>
CELLOXIDE 2021P (celloxide 2021P): 3,4-epoxycyclohexylmethyl (3,4-epoxy) cyclohexanecarboxylate, manufactured by Daicel Corporation <Other epoxy resins>
MA-DGIC: monoallyl diglycidyl isocyanurate, manufactured by Shikoku Chemicals Co., Ltd. X-40-2678: siloxane derivative having two epoxy groups in a molecule, manufactured by Shin-Etsu Chemical Co., Ltd. <acid anhydride curing agent (B)>
MH-700 (Ricacid MH-700): 4-methylhexahydrophthalic anhydride / hexahydrophthalic anhydride = 70/30, manufactured by Shin Nippon Rika Co., Ltd. HN-5700: 4-methylhexahydrophthalic anhydride / 3- Mixture of methylhexahydrophthalic anhydride = 70/30 and alicyclic polyester resin, HN-7200 manufactured by Hitachi Chemical Co., Ltd. Mixture of 4-methylhexahydrophthalic anhydride and alicyclic polyester resin, Hitachi Chemical Co., Ltd. <Thermal cationic curing catalyst (C)>
SI-100L: trade name “Sun-Aid SI-100L”, thermal cation curing catalyst, manufactured by Sanshin Chemical Industry Co., Ltd. SI-110L: trade name “Sun-Aid SI-110L”, thermal cation curing catalyst, Sanshin Chemical Industry Co., Ltd. ) <Metal organic acid salt (D)>
Zinc octylate: trade name "Nikka Octix Zinc (15%)", mineral spirit solution of zinc octylate, Nippon Chemical Industries zinc naphthylate: trade name "Naphtex Zinc (8%)", mineral spirit of zinc naphthylate Solution, zirconium octylate, manufactured by Nippon Kagaku Sangyo: trade name "17% octopus Zr", zirconium 2-ethylhexanoate, containing 27% of ink solvent as a solvent, calcium octylate manufactured by Hope Pharmaceutical Co., Ltd .: trade name "5% octopus" Ca ", calcium 2-ethylhexanoate, 21% by weight of 2-ethylhexanoic acid as a solvent and 38% of mineral spirit, manufactured by Hope Pharmaceutical Co., Ltd. <Epoxy-anhydride curing accelerator>
PX-4MP: trade name "Hishicolin PX-4MP", Nippon Kagaku Sangyo Co., Ltd. U-CAT 5002: trade name "U-CAT 5002", San Apro Co., Ltd. <Antioxidant (E)>
PEP-36: trade name "ADK STAB PEP-36", phosphorus-based antioxidant, manufactured by ADEKA Corporation

  The thermosetting epoxy resin composition of the present invention can be preferably used as a resin composition for encapsulating an optical semiconductor. In addition, the thermosetting epoxy resin composition of the present invention includes, for example, an adhesive, an electrical insulating material, a laminate, a coating, an ink, a paint, a sealant, a resist, a composite material, a transparent substrate, a transparent sheet, a transparent film, and an optical It can also be used for applications such as elements, optical lenses, optical members, stereolithography, electronic paper, touch panels, solar cell substrates, optical waveguides, light guide plates, and holographic memories.

Claims (12)

  One selected from the group consisting of an alicyclic epoxy compound (A), an acid anhydride curing agent (B), a thermal cationic curing catalyst (C), and a metal salt of an organic acid and a metal chelate compound as a curing accelerator. A thermosetting epoxy resin composition comprising the above compound (D).   The thermosetting epoxy resin composition according to claim 1, wherein a curing reaction initiation temperature is 150 ° C or lower.   The amount in which the content of the acid anhydride curing agent (B) is 0.01 to 1.0 equivalent to 1 equivalent of the epoxy group in all the epoxy group-containing compounds contained in the thermosetting epoxy resin composition. The thermosetting epoxy resin composition according to claim 1 or 2, wherein   The thermosetting epoxy resin composition according to any one of claims 1 to 3, wherein the alicyclic epoxy compound (A) is a compound having a cyclohexene oxide group. The alicyclic epoxy compound (A) has the following formula (I-1)

The thermosetting epoxy resin composition according to any one of claims 1 to 4, which is a compound represented by the formula:   The thermosetting epoxy resin composition according to any one of claims 1 to 5, further comprising an antioxidant (E). Further, the following equation (1)

[Wherein, R ¹ and R ² are the same or different and each represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms]
The thermosetting epoxy resin composition according to any one of claims 1 to 6, comprising a monoallyl diglycidyl isocyanurate compound (F) represented by the following formula:   The thermosetting epoxy resin composition according to any one of claims 1 to 7, further comprising a siloxane derivative having two or more epoxy groups in a molecule.   The thermosetting epoxy resin composition according to any one of claims 1 to 8, further comprising an alicyclic polyester resin.   A cured product of the thermosetting epoxy resin composition according to claim 1.   The thermosetting epoxy resin composition according to any one of claims 1 to 9, which is a resin composition for encapsulating an optical semiconductor.   An optical semiconductor device in which an optical semiconductor element is sealed with a cured product of the thermosetting epoxy resin composition according to claim 11.