JP6386907B2 - Curable epoxy resin composition - Google Patents

Description

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

  In recent years, the output of optical semiconductor devices has been increased, and high heat resistance and light resistance are required for a resin (encapsulant) that covers an optical semiconductor element in such an optical semiconductor device. Conventionally, as a sealing agent for forming a sealing material having high heat resistance, for example, a composition containing monoallyl diglycidyl isocyanurate and a bisphenol A type epoxy resin is known (see Patent Document 1). However, when the composition is used as a sealant for a high-power blue / white light semiconductor, the coloring of the sealant proceeds by light or heat emitted from the optical semiconductor element and should be output originally. As a result, the light is absorbed, and as a result, the intensity of the light output from the optical semiconductor device is lowered with time.

  3,4-epoxycyclohexylmethyl (3,4-epoxy) cyclohexanecarboxylate, 3,4 as a sealing agent that forms a cured product (sealing material) that has high heat resistance and light resistance and is not easily yellowed -Liquid alicyclic epoxy resins having an alicyclic skeleton such as an adduct of epoxycyclohexylmethyl (3,4-epoxy) cyclohexanecarboxylate and ε-caprolactone, 1,2,8,9-diepoxylimonene, etc. are known. ing. However, the cured products of these alicyclic epoxy resins are vulnerable to various stresses. For example, when a thermal shock such as a cooling cycle (repeating heating and cooling periodically) is applied, cracks are generated. Problems such as occurrence have occurred.

  In addition, an optical semiconductor device (for example, a surface-mount type optical semiconductor device) generally undergoes a reflow process for bonding an electrode of the optical semiconductor device to a wiring board by soldering. In recent years, lead-free solder having a high melting point has been used as a solder as a bonding material, and heat treatment in a reflow process has become a higher temperature (for example, a peak temperature of 240 to 260 ° C.). . Under such circumstances, in the conventional optical semiconductor device, there is a problem of deterioration such that the sealing material is peeled off from the lead frame of the optical semiconductor device due to the heat treatment in the reflow process, or the sealing material is cracked. Has occurred. Furthermore, even when a sealing material that has been considered to have excellent heat resistance has been used, coloring of the sealing material (yellowing, etc.) proceeds due to high-temperature heat in the reflow process, resulting in a problem that the luminous intensity decreases. It was.

  For this reason, the sealing material in the optical semiconductor device has high heat resistance and light resistance, and also has a characteristic that cracks are not easily generated when a thermal shock is applied (sometimes referred to as “thermal shock resistance”), and Further, there is a demand for characteristics in which cracks and peeling are unlikely to occur even when heat treatment is performed in the reflow process. In particular, in recent years, from the viewpoint of ensuring higher reliability of the sealing material, the optical semiconductor device is kept under high humidity conditions for a certain time (for example, 192 hours under conditions of 30 ° C. and 60% RH; 60 ° C., 60% RH). The above-mentioned cracks and peeling are not likely to occur even when heat treatment is performed in the reflow process after placing and absorbing moisture under the above conditions (for 52 hours, etc.) (this characteristic is sometimes referred to as “moisture absorption reflow resistance”). There is also a need.

JP 2000-344867 A

  When the above-mentioned cracks or peeling occurs in the sealing material in the optical semiconductor device, there arises a problem of quality deterioration such as a decrease in relative luminous intensity (decrease in luminous intensity) or non-lighting of the total light flux of the optical semiconductor device.

Accordingly, an object of the present invention is to provide a curable epoxy resin composition that has excellent heat resistance and thermal shock resistance, and can form a cured product that is suppressed from coloring due to heating (particularly, heating in a reflow process). There is to do.
Another object of the present invention is to provide a cured product having excellent heat resistance and thermal shock resistance, and in particular, coloring suppressed by heating (particularly heating in a reflow process).
Furthermore, another object of the present invention is to provide an optical semiconductor device that is excellent in thermal shock resistance and moisture absorption reflow resistance and is less susceptible to deterioration such as reduction in light intensity due to heating or aging.

  As a result of intensive investigations to solve the above problems, the present inventors have determined that a curable epoxy resin composition containing, as essential components, a specific amount of a specific type of epoxy compound, a specific type of curing agent, and a specific type of curing accelerator. According to the present invention, it was found that a cured product having excellent heat resistance and thermal shock resistance, and in particular, coloring suppressed by heating (particularly heating in the reflow process) can be formed, and the present invention was completed.

［式中、Ｒ¹は、同一又は異なって、炭素数１〜１０のアルキル基、又はアリール基を示す。Ｒ²は、炭素数１〜４のアルキル基を示す。Ｘ^-は、有機スルホン酸の共役塩基を示す。］
で表される化合物（Ｃ−１）、及び下記式（２）

［式中、Ｒ³は、同一又は異なって、炭素数１〜１０のアルキル基、又はアリール基を示す。Ｒ⁴は、炭素数１〜４のアルキル基を示す。Ｚ^-は、酸性リン酸エステルの共役塩基を示す。］
で表される化合物（Ｃ−２）を含むことを特徴とする硬化性エポキシ樹脂組成物を提供する。 That is, the present invention comprises an epoxy compound (A), an acid anhydride curing agent (B), and a quaternary phosphonium salt curing accelerator (C),
As epoxy compound (A), bisphenol A type epoxy resin 30 to 90% by weight and alicyclic epoxy compound 10 to 70% by weight with respect to the total amount (100% by weight) of epoxy compound (A),
As a quaternary phosphonium salt-based curing accelerator (C), the following formula (1)

[In formula, R < ¹ > is the same or different, and shows a C1-C10 alkyl group or an aryl group. R ² represents an alkyl group having 1 to 4 carbon atoms. X ⁻ represents a conjugate base of an organic sulfonic acid. ]
And a compound (C-1) represented by the following formula (2)

[In formula, R < ³ > is the same or different, and shows a C1-C10 alkyl group or an aryl group. R ⁴ represents an alkyl group having 1 to 4 carbon atoms. Z ⁻ represents a conjugate base of an acidic phosphate ester. ]
The curable epoxy resin composition characterized by including the compound (C-2) represented by these is provided.

  Furthermore, the said curable epoxy resin composition whose acid anhydride type hardening | curing agent (B) is a non-aromatic acid anhydride type hardening | curing agent is provided.

  The present invention also provides a cured product obtained by curing the curable epoxy resin composition.

  Furthermore, the said curable epoxy resin composition which is a resin composition for optical semiconductor sealing is provided.

  Moreover, this invention provides the optical semiconductor device by which the optical semiconductor element was sealed with the hardened | cured material of the said curable epoxy resin composition.

  Since the curable epoxy resin composition of the present invention has the above-described configuration, it has excellent heat resistance and thermal shock resistance by curing the resin composition, and particularly by heating (particularly heating in the reflow process). A cured product in which coloring is suppressed is obtained. For this reason, in particular, by using the curable epoxy resin composition of the present invention as a resin composition for optical semiconductor encapsulation, it has excellent thermal shock resistance and moisture absorption reflow resistance, and deterioration such as a decrease in luminous intensity due to heating or aging. An optical semiconductor device that is less likely to occur can be obtained.

It is the schematic which shows one Embodiment of the optical semiconductor device by which the optical semiconductor element was sealed with the hardened | cured material of the curable epoxy resin composition of this invention. The left figure (a) is a perspective view, and the right figure (b) is a sectional view. It is an example of the surface temperature profile (temperature profile in one heat processing among two heat processing) of the optical semiconductor device in the solder heat resistance test of an Example.

<Curable epoxy resin composition>
The curable epoxy resin composition of the present invention comprises an epoxy compound (A), an acid anhydride curing agent (B), and a quaternary phosphonium salt curing accelerator (C) as essential components ( Curable composition). Among them, as described later, the curable epoxy resin composition of the present invention is 30 to 90% by weight of the bisphenol A type epoxy resin with respect to the total amount (100% by weight) of the epoxy compound (A) as the epoxy compound (A). And an alicyclic epoxy compound in an amount of 10 to 70% by weight, and as a quaternary phosphonium salt-based curing accelerator (C), the following compound (C-1) and compound (C-2) are included as essential components. .

[Epoxy compound (A)]
The epoxy compound (A) in the curable epoxy resin composition of the present invention is a compound having at least one epoxy group (oxirane ring) in the molecule, and is arbitrarily selected from known or commonly used epoxy compounds. be able to. Examples of the epoxy compound (A) include bisphenol A type epoxy resin, bisphenol F type epoxy resin, biphenol type epoxy resin, novolac type epoxy resin (for example, phenol novolak type epoxy resin, cresol novolac type epoxy resin, cresol of bisphenol A). Novolak epoxy resins), naphthalene epoxy resins, aromatic epoxy compounds such as epoxy resins obtained from trisphenolmethane (aromatic epoxy resins); aliphatic epoxy compounds such as polyglycidyl ethers of aliphatic polyols (aliphatic epoxy) Resin); alicyclic epoxy compounds (alicyclic epoxy resins), heterocyclic epoxy compounds (heterocyclic epoxy resins), and siloxane derivatives having one or more epoxy groups in the molecule.

  The epoxy compound (A) can be produced by a known or conventional method, or a commercially available product can be obtained.

  Among them, the curable epoxy resin composition of the present invention includes a bisphenol A type epoxy resin (sometimes referred to as “bisphenol A type epoxy resin (A-1)”) and an alicyclic epoxy as the epoxy compound (A). A compound (sometimes referred to as “alicyclic epoxy compound (A-2)”). Thereby, the heat resistance of hardened | cured material, the adhesiveness with respect to a to-be-adhered body, and a thermal shock resistance can be made to stand together. In the curable epoxy resin composition of the present invention, in addition to the bisphenol A type epoxy resin (A-1) and the alicyclic epoxy compound (A-2), other epoxy compounds (A) are used in combination. Also good.

  The bisphenol A type epoxy resin (A-1) is a compound having one or more bisphenol A skeletons and one or more epoxy groups in the molecule, and a well-known and commonly used bisphenol A type epoxy resin can be used. it can.

  Although the epoxy equivalent of a bisphenol A type epoxy resin (A-1) is not specifically limited, 2000 (g / equivalent) or less is preferable, More preferably, it is 1000 or less. By setting the epoxy equivalent of the bisphenol A type epoxy resin (A-1) to 2000 or less, the viscosity of the curable epoxy resin composition does not become too high, and the handleability tends to be improved. Although the minimum of the said epoxy equivalent is not specifically limited, 30 or more are preferable, More preferably, it is 50 or more.

  The weight average molecular weight (Mw) in terms of standard polystyrene of the bisphenol A type epoxy resin (A-1) is not particularly limited, but is preferably 10,000 or less, more preferably 8000 or less. By setting the weight average molecular weight of the bisphenol A type epoxy resin (A-1) to 10,000 or less, the viscosity of the curable epoxy resin composition does not become too high, and the handleability tends to be improved. Although the minimum of the said weight average molecular weight is not specifically limited, 60 or more are preferable, More preferably, it is 100 or more. The weight average molecular weight is measured by a gel permeation chromatography (GPC) method.

  In the curable epoxy resin composition of the present invention, the bisphenol A type epoxy resin (A-1) can be used singly or in combination of two or more. The bisphenol A type epoxy resin (A-1) can also be produced by a known or conventional method. For example, the product name “YD-128” (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.) Commercial products can also be obtained.

  The alicyclic epoxy compound (A-2) is a compound having one or more alicyclic rings (aliphatic hydrocarbon rings) and one or more epoxy groups in the molecule. Examples of the alicyclic epoxy compound (A-2) include (i) an alicyclic epoxy group (an epoxy group composed of two adjacent carbon atoms and oxygen atoms constituting the alicyclic ring) in the molecule. A compound having at least one (preferably two or more); (ii) a compound having an epoxy group bonded directly to the alicyclic ring by a single bond; and (iii) a compound having an alicyclic ring and a glycidyl group.

Although it does not specifically limit as an alicyclic epoxy group which the compound which has at least 1 alicyclic epoxy group in the above-mentioned (i) molecule | numerator has, From a sclerosing | hardenable viewpoint, it adjoins a cyclohexene oxide group (adjacent which comprises a cyclohexane ring). An epoxy group composed of two carbon atoms and an oxygen atom) is preferred. In particular, (i) the compound having at least one alicyclic epoxy group in the molecule is preferably a compound having two or more cyclohexene oxide groups in the molecule from the viewpoint of transparency and heat resistance of the cured product. A compound represented by the following formula (I) is preferable.

  In the above formula (I), A represents a single bond or a linking group (a divalent group having one or more atoms). Examples of the linking group include divalent hydrocarbon groups, alkenylene groups in which part or all of carbon-carbon double bonds are epoxidized, carbonyl groups, ether bonds, ester bonds, carbonate groups, amide groups, and the like. And a group in which a plurality of are connected. In addition, a substituent such as an alkyl group may be bonded to one or more carbon atoms constituting the cyclohexane ring (cyclohexene oxide group) in the formula (I).

  Examples of the compound in which A in the formula (I) is a single bond include 3,4,3 ′, 4′-diepoxybicyclohexane and the like.

  As said bivalent hydrocarbon group, a C1-C18 linear or branched alkylene group, a bivalent alicyclic hydrocarbon group, etc. are mentioned. 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 group, 1,3-cyclopentylene group, cyclopentylidene group, 1,2-cyclohexylene group, 1,3-cyclopentylene group, And divalent cycloalkylene groups (including cycloalkylidene groups) such as cyclohexylene group, 1,4-cyclohexylene group, and cyclohexylidene group.

  Examples of the alkenylene group in the alkenylene group in which part or all of the carbon-carbon double bond is epoxidized (sometimes referred to as “epoxidized alkenylene group”) include, for example, a vinylene group, a propenylene group, and a 1-butenylene group. , 2-butenylene group, butadienylene group, pentenylene group, hexenylene group, heptenylene group, octenylene group, etc., straight chain or branched chain alkenylene groups having 2 to 8 carbon atoms (including alkapolyenylene groups) and the like. . In particular, the epoxidized alkenylene group is preferably an alkenylene group in which all of the carbon-carbon double bonds are epoxidized, more preferably 2 to 4 carbon atoms in which all of the carbon-carbon double bonds are epoxidized. Alkenylene group.

  The linking group A is particularly preferably a linking group containing an oxygen atom, specifically, —CO—, —O—CO—O—, —COO—, —O—, —CONH—, epoxidation. An alkenylene group; a group in which a plurality of these groups are linked; a group in which one or more of these groups are linked to one or more of divalent hydrocarbon groups, and the like. Examples of the divalent hydrocarbon group include those exemplified above.

Representative examples of the compound represented by the formula (I) include compounds represented by the following formulas (I-1) to (I-10), bis (3,4-epoxycyclohexylmethyl) ether, 1, 2-bis (3,4-epoxycyclohexane-1-yl) ethane, 1,2-epoxy-1,2-bis (3,4-epoxycyclohexane-1-yl) ethane, 2,2-bis (3 4-epoxycyclohexane-1-yl) propane and the like. In the following formulas (I-5) and (I-7), l and m 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, methylene group, ethylene group, propylene group, isopropylene group, butylene group, isobutylene group, s-butylene group, pentylene group, hexylene. And linear or branched alkylene groups such as a group, a heptylene group, and an octylene group. Among these, C1-C3 linear or branched alkylene groups, such as a methylene group, ethylene group, a propylene group, an isopropylene group, are preferable. N1 to n6 in the following formulas (I-9) and (I-10) each represent an integer of 1 to 30.

Examples of the compound (ii) having an epoxy group bonded directly to the alicyclic ring with a single bond include compounds represented by the following formula (II).

In the formula (II), R ′ is a group (p-valent organic group) obtained by removing p hydroxyl groups (—OH) from the structural formula of p-valent alcohol in the structural formula, and p and n are natural numbers, respectively. Represents. Examples of the p-valent alcohol [R ′ (OH) _p ] include polyhydric alcohols (such as alcohols having 1 to 15 carbon atoms) such as 2,2-bis (hydroxymethyl) -1-butanol. p is preferably 1 to 6, and n is preferably 1 to 30. When p is 2 or more, n in each group in () (inside the outer parenthesis) may be the same or different. Specific examples of the compound represented by the above formula (II) include 1,2-epoxy-4- (2-oxiranyl) cyclohexane adduct of 2,2-bis (hydroxymethyl) -1-butanol [for example, , Trade name “EHPE3150” (manufactured by Daicel Corporation), etc.].

  Examples of the compound (iii) having an alicyclic ring and a glycidyl group include 2,2-bis [4- (2,3-epoxypropoxy) cyclohexyl] propane, 2,2-bis [3,5 -Dimethyl-4- (2,3-epoxypropoxy) cyclohexyl] propane, hydrogenated bisphenol A type epoxy resin (hydrogenated bisphenol A type epoxy resin), etc .; bis [o, o- (2,3 -Epoxypropoxy) cyclohexyl] methane, bis [o, p- (2,3-epoxypropoxy) cyclohexyl] methane, bis [p, p- (2,3-epoxypropoxy) cyclohexyl] methane, Bis [3,5-dimethyl-4- (2,3-epoxypropoxy) cyclohexyl] methane, hydrogenated bisphenol F type epoxy resin (hydrogenated bisphenol Nordic F type epoxy resin); Hydrogenated biphenol type epoxy resin; Hydrogenated novolak type epoxy resin (for example, hydrogenated phenol novolak type epoxy resin, hydrogenated cresol novolak type epoxy resin, hydrogenated cresol novolak type epoxy resin of bisphenol A) Etc.); Hydrogenated naphthalene type epoxy resin; Hydrogenated epoxy resin of epoxy resin obtained from trisphenol methane and the like.

  Other examples of the alicyclic epoxy compound (A-2) include 1,2,8,9-diepoxy limonene.

  In the curable epoxy resin composition of the present invention, the alicyclic epoxy compound (A-2) can be used singly or in combination of two or more. The alicyclic epoxy compound (A-2) can also be obtained by a known or conventional method. For example, trade names “Celoxide 2021P”, “Celoxide 2081” (above, manufactured by Daicel Corporation), etc. Commercial products can also be obtained.

  Examples of the alicyclic epoxy compound (A-2) include a compound represented by the formula (I-1) [3,4-epoxycyclohexylmethyl (3,4-epoxy) cyclohexanecarboxylate; for example, trade name “Celoxide 2021P”. "(Daicel Co., Ltd.) etc.] is particularly preferable.

  The content (blending amount) of the epoxy compound (A) in the curable epoxy resin composition of the present invention is not particularly limited, but is 10 to 95% by weight with respect to the curable epoxy resin composition (100% by weight). It is preferably 20 to 80% by weight, more preferably 30 to 60% by weight. By controlling the content of the epoxy compound (A) in the above range, the curability of the curable epoxy resin composition tends to be improved, and the heat resistance and mechanical strength of the cured product tend to be further improved.

  The content (blending amount) of the bisphenol A type epoxy resin (A-1) in the curable epoxy resin composition of the present invention is 30 to 90% by weight with respect to the total amount (100% by weight) of the epoxy compound (A). Yes, preferably 40 to 85% by weight, more preferably 50 to 80% by weight. By setting the content of the bisphenol A type epoxy resin (A-1) to 30% by weight or more, the adhesion of the cured product to the adherend is improved. On the other hand, by setting the content of the bisphenol A type epoxy resin (A-1) to 90% by weight or less, the thermal shock resistance of the cured product is improved, and coloring due to heating is suppressed.

  The content (blending amount) of the alicyclic epoxy compound (A-2) in the curable epoxy resin composition of the present invention is 10 to 70% by weight with respect to the total amount (100% by weight) of the epoxy compound (A). Yes, preferably 15 to 60% by weight, more preferably 20 to 50% by weight. By setting the content of the alicyclic epoxy compound (A-2) to 10% by weight or more, the curability of the curable epoxy resin composition and the heat resistance of the cured product are improved. On the other hand, by setting the content of the alicyclic epoxy compound (A-2) to 70% by weight or less, the thermal shock resistance of the cured product is improved.

  The total amount of the bisphenol A type epoxy resin (A-1) and the alicyclic epoxy compound (A-2) with respect to the total amount (100% by weight) of the epoxy compound (A) contained in the curable epoxy resin composition of the present invention. The ratio is not particularly limited, but is preferably 70% by weight or more (for example, 70 to 100% by weight), more preferably 80% by weight or more (for example, 80 to 99% by weight), and still more preferably 90% by weight or more (for example, 90-98% by weight). Especially, it is preferable that an epoxy compound (A) consists only of a bisphenol A type epoxy resin (A-1) and an alicyclic epoxy compound (A-2) (the said ratio is 100 weight%). When the ratio is 70% by weight or more, the curability of the curable epoxy resin composition, the heat resistance of the cured product, the thermal shock resistance, and the adhesion to the adherend are improved.

[Acid anhydride curing agent (B)]
The acid anhydride curing agent (B) in the curable epoxy resin composition of the present invention is a compound having a function of curing the curable epoxy resin composition by reacting with the epoxy compound (A). Moreover, among the many curing agents for epoxy resins, in particular, by using the acid anhydride curing agent (B), coloring during curing is suppressed, and a cured product having excellent hue can be obtained.

  As the acid anhydride-based curing agent (B), known and commonly used acid anhydrides can be used as a curing agent for epoxy resins, and are not particularly limited. For example, methyltetrahydrophthalic anhydride (4-methyltetrahydroanhydride) Phthalic acid, 3-methyltetrahydrophthalic anhydride, etc.), methylhexahydrophthalic anhydride (4-methylhexahydrophthalic anhydride, 3-methylhexahydrophthalic anhydride, etc.), dodecenyl succinic anhydride, methylendomethylenetetrahydroanhydride Phthalic acid, phthalic anhydride, maleic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylcyclohexene dicarboxylic anhydride, pyromellitic anhydride, trimellitic anhydride, benzophenone tetracarboxylic anhydride, nadic anhydride, anhydrous Methyl nadic acid (1-methyl anhydride Dic acid, 5-methyl nadic anhydride, etc.), hydrogenated methyl nadic anhydride, 4- (4-methyl-3-pentenyl) tetrahydrophthalic anhydride, succinic anhydride, adipic anhydride, sebacic anhydride, dodecane anhydride Diacid, methylcyclohexene tetracarboxylic anhydride, vinyl ether-maleic anhydride copolymer, methylnorbornane-2,3-dicarboxylic anhydride (1-methylnorbornane-2,3-dicarboxylic anhydride, 5-methylnorbornane -2,3-dicarboxylic acid anhydride), norbornane-2,3-dicarboxylic acid anhydride, and the like. Among these, acid anhydrides [for example, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, dodecenyl succinic anhydride, methylendomethylenetetrahydrophthalic anhydride, etc.] that are liquid at 25 ° C. are preferable from the viewpoint of handleability. On the other hand, for the acid anhydride that is solid at 25 ° C., for example, the acid anhydride system in the curable epoxy resin composition of the present invention is dissolved in a liquid acid anhydride at 25 ° C. to form a liquid mixture. There exists a tendency for the handleability as a hardening | curing agent (B) to improve. Moreover, as an acid anhydride type hardening | curing agent (B), a non-aromatic acid anhydride (non-aromatic acid anhydride type hardening | curing agent) is preferable from a heat resistant and transparency viewpoint of hardened | cured material, More preferably, it is saturated. Monocyclic hydrocarbon dicarboxylic acid anhydrides (including those having a substituent such as an alkyl group bonded to the ring).

  In addition, in the curable epoxy resin composition of this invention, an acid anhydride type hardening | curing agent (B) can also be used individually by 1 type, and can also be used in combination of 2 or more type. The acid anhydride-based curing agent (B) can also be produced by a known or conventional method. For example, trade names “Licacid MH-700”, “Licacid MH-700F” (above, Shin Nippon Rika) Commercially available products such as trade name “HN-5500” (manufactured by Hitachi Chemical Co., Ltd.) can also be obtained.

  The content (blending amount) of the acid anhydride-based curing agent (B) in the curable epoxy resin composition of the present invention is not particularly limited, but the total amount of compounds having an epoxy group contained in the curable epoxy resin composition is 100. 50-200 weight part is preferable with respect to a weight part, More preferably, it is 80-150 weight part. More specifically, it is preferably used at a ratio of 0.5 to 1.5 equivalents per 1 equivalent of epoxy groups in all compounds having an epoxy group contained in the curable epoxy resin composition of the present invention. By setting the content of the acid anhydride-based curing agent (B) to 50 parts by weight or more, curing can sufficiently proceed, and the toughness of the cured product tends to be further improved. On the other hand, by setting the content of the acid anhydride curing agent (B) to 200 parts by weight or less, coloring tends to be suppressed and a cured product excellent in hue tends to be obtained.

  In the curable epoxy resin composition of the present invention, a curing agent (other curing agent) other than the acid anhydride curing agent (B) can be used in combination. Examples of other curing agents include amines (amine curing agents), polyamide resins, imidazoles (imidazole curing agents), polymercaptans (polymercaptan curing agents), phenols (phenol curing agents), Polycarboxylic acids, dicyandiamides, organic acid hydrazides and the like can be mentioned. Although the usage-amount of another hardening | curing agent is not specifically limited, It can select suitably from the range of 0-20 weight% (especially 0-5 weight%) with respect to the whole quantity (100 weight%) of a hardening | curing agent.

[Quaternary phosphonium salt curing accelerator (C)]
The quaternary phosphonium salt curing accelerator (C) in the curable epoxy resin composition of the present invention is a salt composed of a phosphonium ion and its counter ion (anion). The quaternary phosphonium salt-based curing accelerator (C) is not particularly limited as long as it is composed of a phosphonium ion and its counter ion. For example, it is known or commonly used such as tetraphenylphosphonium tetra (p-tolyl) borate. A compound (quaternary phosphonium salt) can be used. The quaternary phosphonium salt-based curing accelerator (C) can be produced by a known or commonly used method, or a commercially available product can be obtained.

Among them, the curable epoxy resin composition of the present invention may be referred to as a compound represented by the following formula (1) (“compound (C-1)”) as the quaternary phosphonium salt-based curing accelerator (C). And a compound represented by the following formula (2) (sometimes referred to as “compound (C-2)”). Thereby, coloring of the hardened | cured material by heating, especially coloring by the heating in a reflow process are suppressed highly. In the curable epoxy resin composition of the present invention, in addition to the compound (C-1) and the compound (C-2), other quaternary phosphonium salt curing accelerators (C) may be used in combination. .

In formula (1), R ¹ are the same or different and are each an alkyl group, or aryl group having 1 to 10 carbon atoms. Examples of the alkyl group having 1 to 10 carbon atoms include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group, t-butyl group, n-pentyl group, and isopentyl group. , S-pentyl group, t-pentyl group, neopentyl group, n-hexyl group, isohexyl group, s-hexyl group, t-hexyl group, neohexyl group, heptyl group, octyl group, 2-ethylhexyl group, nonyl group, decyl A linear or branched alkyl group having 1 to 10 carbon atoms such as a group; a cyclic alkyl group having 3 to 10 carbon atoms (cycloalkyl group) such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, methylcyclohexyl group, etc. Etc. Examples of the aryl group include a phenyl group, a substituted phenyl group (for example, a tolyl group, a xylyl group, a mesityl group, an ethylphenyl group, a methoxyphenyl group, an ethoxyphenyl group), and a naphthyl group. Among them, R ¹ in the formula (1) is preferably an aryl group, more preferably a phenyl group or a substituted phenyl group, from the viewpoint of curability of the curable epoxy resin composition and suppression of coloring of the cured product by heating. .

In formula (1), R ² represents an alkyl group having 1 to 4 carbon atoms. Examples of the alkyl group having 1 to 4 carbon atoms include straight chain having 1 to 4 carbon atoms such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, s-butyl group, and t-butyl group. Or a branched alkyl group is mentioned. Among them, R ² in the formula (1) is preferably a linear or branched alkyl group having 1 to 3 carbon atoms from the viewpoint of curability of the curable epoxy resin composition and suppression of coloring of the cured product by heating. And more preferably a methyl group or an ethyl group.

In the formula (1), X ⁻ represents a conjugate base of an organic sulfonic acid. As said organic sulfonic acid, well-known thru | or usual organic sulfonic acid is mentioned, It does not specifically limit. Specifically, as X ⁻ (conjugated base of organic sulfonic acid), for example, a conjugate base of aliphatic sulfonic acid represented by the following formula (1a), an aromatic sulfonic acid represented by the following formula (1b) And the like. In particular, X ⁻ in formula (1) is a conjugate base of an aliphatic sulfonic acid represented by formula (1a) or an aromatic represented by formula (1b) from the viewpoint of suppressing coloring of a cured product by heating. A conjugated base of sulfonic acid is preferred.

In the formula (1a), R ^a represents a linear or branched alkyl group having 1 to 16 carbon atoms. As R ^a , methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group, t-butyl group, n-pentyl group, isopentyl group, s-pentyl group, t-pentyl group, neopentyl group, n-hexyl group, isohexyl group, s-hexyl group, s-hexyl group, t-hexyl group, neohexyl group, heptyl group, octyl group, 2-ethylhexyl group, nonyl group, decyl group C1-C12 linear or branched alkyl groups, such as a dodecyl group, are preferable, More preferably, it is a C1-C4 linear or branched alkyl group, More preferably, it is a methyl group.

  More specifically, examples of the conjugate base of the aliphatic sulfonic acid represented by the formula (1a) include methanesulfonic acid, ethanesulfonic acid, 1-propanesulfonic acid, 2-propanesulfonic acid, 1-butanesulfonic acid, Examples thereof include conjugate bases of aliphatic sulfonic acids such as 1-pentanesulfonic acid, 1-hexanesulfonic acid, 1-octanesulfonic acid, 1-decanesulfonic acid, and 1-dodecanesulfonic acid.

  Especially, as a conjugate base of aliphatic sulfonic acid represented by Formula (1a), a conjugate base of methanesulfonic acid is preferable.

In formula (1b), R ^{b to} R ^f are the same or different and each represents a hydrogen atom, a linear or branched alkyl group having 1 to 16 carbon atoms, an alkoxy group, or a halogen atom. As the linear or branched alkyl group having 1 to 16 carbon atoms as R ^{b to} R ^f , in particular, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group , T-butyl group, n-pentyl group, isopentyl group, s-pentyl group, t-pentyl group, neopentyl group, n-hexyl group, s-hexyl group, t-hexyl group, neopentyl group, heptyl group, octyl group , A linear or branched alkyl group having 1 to 12 carbon atoms such as 2-ethylhexyl group, nonyl group, decyl group, undecyl group, dodecyl group, etc. is preferable, and linear or branched chain having 1 to 3 carbon atoms is more preferable. Alkyl group, more preferably methyl group.

Examples of the alkoxy group as R ^{b to} R ^f include linear or branched alkoxy groups having 1 to 6 carbon atoms such as a methoxy group, an ethoxy group, and a propoxy group. Of these, a methoxy group and an ethoxy group are preferable. As a halogen atom as ^{Rb- Rf} , a fluorine atom, a chlorine atom, a bromine atom, an iodine atom etc. are mentioned, for example. Among these, a chlorine atom is preferable.

  More specifically, examples of the conjugate base of the aromatic sulfonic acid represented by the formula (1b) include benzenesulfonic acid, monoalkylbenzenesulfonic acid, dialkylbenzenesulfonic acid, monoalkoxybenzenesulfonic acid, monohalobenzenesulfonic acid, and the like. And the conjugate base of aromatic sulfonic acid. Examples of the monoalkylbenzene sulfonic acid include 2-, 3-, or 4-mono (linear or branched alkyl having 1 to 12 carbon atoms) benzene sulfonic acid, and more specifically, p- Toluenesulfonic acid, 4-ethylbenzenesulfonic acid, 3- (linear or branched octyl) benzenesulfonic acid, 4- (linear or branched octyl) benzenesulfonic acid, 3- (linear or branched dodecyl) ) Benzenesulfonic acid, 4- (linear or branched dodecyl) benzenesulfonic acid and the like. Examples of the dialkylbenzenesulfonic acid include di (C1-C12 linear or branched alkyl) benzenesulfonic acid, and more specifically, 2,4-dimethylbenzenesulfonic acid, 2, 5-dimethylbenzenesulfonic acid etc. are mentioned. Examples of the monoalkoxybenzenesulfonic acid include mono (C1-C6 linear or branched alkoxy) benzenesulfonic acid, and more specifically, 4-methoxybenzenesulfonic acid, 4-ethoxy. Examples thereof include benzenesulfonic acid. Examples of the monohalobenzene sulfonic acid include 4-chlorobenzene sulfonic acid.

  Among them, as the conjugate base of the aromatic sulfonic acid represented by the formula (1b), in particular, the conjugate base of benzenesulfonic acid, the conjugate base of 4-chlorobenzenesulfonic acid, the conjugate base of n-dodecylbenzenesulfonic acid, the branched chain Preferred is a conjugated base of dodecylbenzenesulfonic acid.

In particular, X ⁻ in formula (1) is preferably a conjugate base of methanesulfonic acid.

  A compound (C-1) can also be used individually by 1 type, and can also be used in combination of 2 or more type. Compound (C-1) can be obtained by a well-known and commonly used production method (for example, the production method disclosed in JP 2010-106131 A), or a commercially available product can be obtained.

In formula (2), R < ³ > is the same or different and shows a C1-C10 alkyl group or an aryl group. Examples of the alkyl group having 1 to 10 carbon atoms include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group, t-butyl group, n-pentyl group, and isopentyl group. , S-pentyl group, t-pentyl group, neopentyl group, n-hexyl group, isohexyl group, s-hexyl group, t-hexyl group, neohexyl group, heptyl group, octyl group, 2-ethylhexyl group, nonyl group, decyl A linear or branched alkyl group having 1 to 10 carbon atoms such as a group; a cyclic alkyl group having 3 to 10 carbon atoms (cycloalkyl group) such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, methylcyclohexyl group, etc. Etc. Examples of the aryl group include a phenyl group, a substituted phenyl group (for example, a tolyl group, a xylyl group, a mesityl group, an ethylphenyl group, a methoxyphenyl group, an ethoxyphenyl group), and a naphthyl group. Among them, R ³ in the formula (2) is preferably a linear or branched alkyl group having 1 to 10 carbon atoms from the viewpoint of curability of the curable epoxy resin composition and suppression of coloring of the cured product by heating. More preferably a linear or branched alkyl group having 1 to 6 carbon atoms.

In formula (2), R ⁴ represents an alkyl group having 1 to 4 carbon atoms. Examples of the alkyl group having 1 to 4 carbon atoms include straight chain having 1 to 4 carbon atoms such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, s-butyl group, and t-butyl group. Or a branched alkyl group is mentioned. Among them, R ⁴ in the formula (2) is preferably a linear or branched alkyl group having 1 to 3 carbon atoms from the viewpoint of curability of the curable epoxy resin composition and suppression of coloring of the cured product by heating. More preferably, it is a methyl group.

In the formula (2), Z ⁻ represents a conjugate base of an acidic phosphate ester. Examples of the acidic phosphate ester include known or commonly used acidic phosphate esters, and are not particularly limited. For example, phosphoric acid monoesters (such as phosphoric acid monoalkyl esters), phosphoric acid diesters (such as phosphoric acid dialkyl esters) Etc. More specifically, Z ⁻ (acidic phosphate ester conjugate base) is preferably an acidic phosphate ester conjugate base represented by the following formula (2a) from the viewpoint of suppressing coloring of the cured product by heating.

In formula (2a), R ^g and R ^h are the same or different and each represents an alkyl group having 1 to 10 carbon atoms or an aryl group. Specific examples of R ^g and R ^h include the same groups as those exemplified as R ³ . Among them, R ^g and R ^h in the formula (2a) are linear or branched alkyl having 1 to 10 carbon atoms from the viewpoint of curability of the curable epoxy resin composition and suppression of coloring of the cured product by heating. Group is preferable, more preferably a linear or branched alkyl group having 1 to 4 carbon atoms, and still more preferably a methyl group or an ethyl group.

  A compound (C-2) can also be used individually by 1 type, and can also be used in combination of 2 or more type. Compound (C-2) can be obtained by a well-known and commonly used production method, and for example, a commercial product such as trade name “Hishicolin PX-4MP” (manufactured by Nippon Chemical Industry Co., Ltd.) can also be obtained.

In addition, as a quaternary phosphonium salt type hardening accelerator (C), only a compound (C-1) and a compound (C-2) can also be used, and a compound (C-1) and a compound (C- A compound other than 2) (for example, a compound having a halogen anion instead of X ⁻ in formula (1)) can be used in combination.

  Although the content (blending amount) of the quaternary phosphonium salt-based curing accelerator (C) in the curable epoxy resin composition of the present invention is not particularly limited, the compound having an epoxy group contained in the curable epoxy resin composition The amount is preferably 0.01 to 10 parts by weight, more preferably 0.05 to 5 parts by weight, and still more preferably 0.1 to 3 parts by weight with respect to 100 parts by weight of the total amount. By controlling the content of the quaternary phosphonium salt (C) within the above range, the curability of the curable epoxy resin composition is further improved, and coloring of the cured product due to heating tends to be further suppressed.

  The content (blending amount) of the compound (C-1) in the curable epoxy resin composition of the present invention is not particularly limited, but the total amount (100% by weight) of the quaternary phosphonium salt-based curing accelerator (C). On the other hand, 10 to 90 weight% is preferable, More preferably, it is 20 to 80 weight%, More preferably, it is 30 to 70 weight%. By setting the content of the compound (C-1) to 10% by weight or more, the heat resistance of the cured product (particularly moisture absorption reflow resistance of the optical semiconductor device) is further improved, and coloring of the cured product by heating is further suppressed. Tend to be. On the other hand, by setting the content of the compound (C-1) to 90% by weight or less, the heat resistance of the cured product (particularly moisture absorption reflow resistance of the optical semiconductor device) and the thermal shock resistance are further improved, and curing by heating. There is a tendency that coloring of an object is more suppressed.

  The content (blending amount) of the compound (C-2) in the curable epoxy resin composition of the present invention is not particularly limited, but the total amount (100% by weight) of the quaternary phosphonium salt-based curing accelerator (C). On the other hand, 10 to 90 weight% is preferable, More preferably, it is 20 to 80 weight%, More preferably, it is 30 to 70 weight%. By setting the content of the compound (C-2) to 10% by weight or more, the heat resistance of the cured product (especially moisture absorption reflow resistance of the optical semiconductor device) and the thermal shock resistance are further improved. There exists a tendency for coloring to be suppressed more. On the other hand, by setting the content of the compound (C-2) to 90% by weight or less, the heat resistance of the cured product (particularly moisture absorption reflow resistance of the optical semiconductor device) is further improved, and the cured product is colored by heating. There is a tendency to be more suppressed.

  The ratio (weight basis) of the compound (C-1) and the compound (C-2) contained in the curable epoxy resin composition of the present invention [compound (C-1) / compound (C-2)] Although not limited, 10 / 90-90 / 10 are preferable, More preferably, it is 30 / 70-70 / 30. By controlling the ratio within the above range, coloring of the cured product due to heating tends to be highly suppressed.

  Ratio of the total amount of the compound (C-1) and the compound (C-2) with respect to the total amount (100% by weight) of the quaternary phosphonium salt-based curing accelerator (C) contained in the curable epoxy resin composition of the present invention. Is not particularly limited, but is preferably 80% by weight or more (for example, 80 to 100% by weight), more preferably 90% by weight or more (for example, 90 to 97% by weight), and still more preferably 95% by weight or more. Especially, it is preferable that a quaternary phosphonium salt type | system | group hardening accelerator (C) consists only of a compound (C-1) and a compound (C-2) (the said ratio is 100 weight%). By setting the ratio to 80% by weight or more, coloring of the cured product due to heating tends to be remarkably suppressed.

  In the curable epoxy resin composition of the present invention, a curing accelerator (other curing accelerator) other than the quaternary phosphonium salt-based curing accelerator (C) can be used in combination. Other curing accelerators include, for example, 1,8-diazabicyclo [5.4.0] undecene-7 (DBU) or a salt thereof (for example, phenol salt, octylate, p-toluenesulfonate, formate) 1,5-diazabicyclo [4.3.0] nonene-5 (DBN) or a salt thereof (eg, phenol salt, octylate, p-toluenesulfonate, formate, tetra Phenylborate salts, etc.); tertiary amines such as benzyldimethylamine, 2,4,6-tris (dimethylaminomethyl) phenol, N, N-dimethylcyclohexylamine; tetraalkylammonium salts, trialkylmonoarylammonium salts, dialkyls Diarylammonium salt, monoalkyltriarylammonium salt, tetraarylanne Quaternary ammonium salts such as nium salts; imidazoles such as 2-ethyl-4-methylimidazole and 1-cyanoethyl-2-ethyl-4-methylimidazole; phosphines such as phosphate esters and triphenylphosphine; zinc octylate And organic metal salts such as tin octylate; metal chelates and the like. Although the usage-amount of another hardening accelerator is not specifically limited, It can select suitably from the range of 0-20 weight% (especially 0-5 weight%) with respect to the whole quantity (100 weight%) of a hardening accelerator. is there.

[Additive]
In addition to the above, the curable epoxy resin composition of the present invention may contain various additives within a range that does not impair the effects of the present invention. For example, when a compound having a hydroxy group such as ethylene glycol, diethylene glycol, propylene glycol, or glycerin is contained as the additive, the reaction can be allowed to proceed slowly. In addition, silicone and fluorine-based antifoaming agents, leveling agents, and silane coupling agents (for example, γ-glycidoxypropyltrimethoxysilane and 3-mercaptopropyltrimethoxy) are used as long as the viscosity and transparency are not impaired. Silane, etc.), surfactants, inorganic fillers (eg, silica, alumina, etc.), flame retardants, colorants, antioxidants, UV absorbers, ion adsorbers, pigments, phosphors (eg, YAG phosphors) Conventional additives such as fine particles, inorganic phosphor fine particles such as silicate phosphor fine particles, etc.), mold release agents, rubber particles (for example, rubber particles having a core-shell structure, etc.) can be used.

  Although the curable epoxy resin composition of this invention is not specifically limited, It can prepare by stirring and mixing each said component in the state heated as needed. In addition, the curable epoxy resin composition of the present invention can be used as a one-component composition in which each component is mixed in advance, for example, two or more stored separately. These components can also be used as a multi-liquid composition (for example, a two-liquid system) that is used by mixing them at a predetermined ratio before use. The stirring / mixing method is not particularly limited, and for example, known or conventional stirring / mixing means such as various mixers such as a dissolver and a homogenizer, a kneader, a roll, a bead mill, and a self-revolving stirrer can be used. Further, after stirring and mixing, defoaming may be performed under reduced pressure or under vacuum.

  Although the viscosity in 25 degreeC of the curable epoxy resin composition of this invention is not specifically limited, 60-10000 mPa * s is preferable, More preferably, it is 100-9000 mPa * s, More preferably, it is 150-8000 mPa * s. By setting the viscosity at 25 ° C. to 60 mPa · s or more, workability at the time of casting tends to be improved, and heat resistance of the cured product tends to be further improved. On the other hand, when the viscosity at 25 ° C. is 10000 mPa · s or less, workability at the time of casting tends to be improved, and defects derived from poor casting in the cured product tend not to occur. The viscosity of the curable epoxy resin composition of the present invention at 25 ° C. is measured using a digital viscometer (model number “DVU-EII type”, manufactured by Tokimec Co., Ltd.), rotor: standard 1 ° 34 ′ × R24, It is measured under the conditions of temperature: 25 ° C. and rotation speed: 0.5 to 10 rpm.

<Hardened product>
By curing the curable epoxy resin composition of the present invention, it has excellent heat resistance and thermal shock resistance, and in particular, a cured product in which coloring due to heating (particularly heating in the reflow process) is suppressed (of the present invention) A cured product obtained by curing the curable epoxy resin composition may be referred to as “cured product of the present invention”). As the curing means, known or conventional means such as heat treatment or light irradiation treatment can be used. Although the temperature (curing temperature) at the time of making it harden | cure by heating is not specifically limited, 45-200 degreeC is preferable, More preferably, it is 50-190 degreeC, More preferably, it is 55-180 degreeC. In addition, the heating time (curing time) for curing is not particularly limited, but is preferably 30 to 600 minutes, more preferably 45 to 540 minutes, and still more preferably 60 to 480 minutes. When the curing temperature and the curing time are lower than the lower limit value in the above range, curing is insufficient. On the contrary, when the curing temperature and the curing time are higher than the upper limit value in the above range, the resin component may be decomposed. Although the curing conditions depend on various conditions, for example, when the curing temperature is increased, the curing time can be shortened, and when the curing temperature is decreased, the curing time can be appropriately increased. Further, the curing can be performed in one stage, or can be performed in two or more stages.

<Resin composition for optical semiconductor encapsulation>
The curable epoxy resin composition of the present invention is a resin composition for sealing an optical semiconductor element in an optical semiconductor device, that is, an optical semiconductor sealing resin composition (an optical semiconductor element sealing agent in an optical semiconductor device). ) Can be preferably used. By using the curable epoxy resin composition of the present invention as a resin composition for encapsulating an optical semiconductor, it has excellent heat resistance and thermal shock resistance, and in particular, coloring due to heating (particularly heating in the reflow process) is suppressed. An optical semiconductor device in which the optical semiconductor element is sealed with the cured product thus obtained is obtained. The optical semiconductor device is excellent in thermal shock resistance and moisture absorption reflow resistance, and has high durability, such as being less susceptible to deterioration such as heating and a decrease in luminous intensity over time.

<Optical semiconductor device>
The optical semiconductor device of the present invention is an optical semiconductor device in which an optical semiconductor element is sealed with a cured product of the curable epoxy resin composition (resin composition for optical semiconductor sealing) of the present invention. The optical semiconductor element can be sealed, for example, by injecting the curable epoxy resin composition prepared by the above-described method into a predetermined mold and curing it under predetermined conditions. Thereby, the optical semiconductor device with which the optical semiconductor element was sealed with the hardened | cured material of the curable epoxy resin composition is obtained. The curing temperature and the curing time are not particularly limited, and can be appropriately set within the same range as that at the time of preparing the cured product, for example.

  The curable epoxy resin composition of the present invention is not limited to the above-mentioned optical semiconductor element sealing application, for example, an adhesive, an electrical insulating material, a laminate, a coating, an ink, a paint, a sealant, a resist, a composite material, Used for various applications such as transparent substrates, transparent sheets, transparent films, optical elements, optical lenses, optical members, stereolithography, electronic paper, touch panels, solar cell substrates, optical waveguides, light guide plates, holographic memories, optical pickup sensors, etc. can do.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples. In Table 1, “-” means that the component was not blended. Moreover, the unit of the quantity (ratio) of the component shown in Table 1 is a weight part.

Production Example 1
(Production of methyltriphenylphosphonium methanesulfonate)
In a stirring autoclave, 120 parts by weight of dimethyl carbonate, 120 parts by weight of methanol, and 262 parts by weight of triphenylphosphine were charged and reacted at a reaction temperature of 120 ° C. for 10 hours to prepare a methanol solution of methyltriphenylphosphonium monomethyl carbonate. Obtained.
Next, 24 parts by weight of the methanol solution of methyltriphenylphosphonium monomethyl carbonate obtained above is gradually added to a reaction vessel containing 98 parts by weight of methanesulfonic acid to remove the generated carbon dioxide gas, and the pressure is further reduced. Residual methanol was removed to obtain methyltriphenylphosphonium methanesulfonate.

Production Example 2
(Production of ethyltriphenylphosphonium methanesulfonate)
Except that dimethyl carbonate was changed to 150 parts by weight of diethyl carbonate, the same operation as in Production Example 1 was performed to obtain ethyl triphenylphosphonium methanesulfonate.

Production Example 3
(Manufacture of epoxy curing agent)
Curing agent (trade name “Licacid MH-700”, manufactured by Shin Nippon Rika Co., Ltd.), 100 parts by weight of methyltriphenylphosphonium methanesulfonate, trade name “PX-4MP” (Nippon Chemical Industry ( 0.5 parts by weight) and 1 part by weight of ethylene glycol (manufactured by Wako Pure Chemical Industries, Ltd.) are mixed into a self-revolving stirrer (trade name “Awatori Nertaro AR-250”, Shinky Corporation) Manufactured, the same applies hereinafter) to prepare an epoxy curing agent (K agent).

Production Example 4
(Manufacture of epoxy curing agent)
100 parts by weight of curing agent (trade name “Licacid MH-700”, manufactured by Shin Nippon Rika Co., Ltd.), 0.5 part by weight of ethyltriphenylphosphonium methanesulfonate, trade name “PX-4MP” (Nippon Chemical Industry ( 0.5 parts by weight) and 1 part by weight of ethylene glycol (manufactured by Wako Pure Chemical Industries, Ltd.) were mixed using a self-revolving stirrer to produce an epoxy curing agent (K agent).

Production Example 5
(Manufacture of epoxy curing agent)
100 parts by weight of a curing agent (trade name “Licacid MH-700”, manufactured by Shin Nippon Rika Co., Ltd.), 1.0 part by weight of methyltriphenylphosphonium methanesulfonate, and ethylene glycol (manufactured by Wako Pure Chemical Industries, Ltd.) ) 1 part by weight was mixed using a self-revolving stirrer to produce an epoxy curing agent (K agent).

Production Example 6
(Manufacture of epoxy curing agent)
Curing agent (trade name “Licacid MH-700”, manufactured by Shin Nippon Rika Co., Ltd.) 100 parts by weight, product name “PX-4MP” (manufactured by Nippon Chemical Industry Co., Ltd.) 1.0 part by weight, and ethylene glycol ( 1 part by weight of Wako Pure Chemical Industries, Ltd.) was mixed using a self-revolving stirrer to produce an epoxy curing agent (K agent).

Production Example 7
(Manufacture of epoxy curing agent)
Curing agent (trade name “Licacid MH-700”, manufactured by Shin Nippon Rika Co., Ltd.) 100 parts by weight, product name “U-CAT 18X” (manufactured by San Apro Co., Ltd.) 1.0 part by weight, and ethylene glycol (Japanese) 1 part by weight of Kojun Pharmaceutical Co., Ltd.) was mixed using a self-revolving stirrer to produce an epoxy curing agent (K agent).

Production Example 8
(Manufacture of epoxy curing agent)
Curing agent (trade name “Licacid MH-700”, manufactured by Shin Nippon Rika Co., Ltd.) 100 parts by weight, methyltriphenylphosphonium methanesulfonate 0.5 part by weight, trade name “U-CAT 18X” (San Apro Co., Ltd.) )) 0.5 parts by weight and 1 part by weight of ethylene glycol (manufactured by Wako Pure Chemical Industries, Ltd.) were mixed using a self-revolving stirrer to produce an epoxy curing agent (K agent).

Examples 1-3
First, the product name “Celoxide 2021P” (manufactured by Daicel Co., Ltd.) and the product name “YD-128” (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.) at the blending ratios shown in Table 1 Were mixed uniformly and defoamed to obtain an epoxy resin (composition).
Next, the epoxy resin obtained above and the epoxy curing agent obtained in Production Example 3 are uniformly mixed using a self-revolving stirrer and defoamed so that the blending ratio shown in Table 1 is obtained. Thus, a curable epoxy resin composition was obtained.
Further, the curable epoxy resin composition obtained above was cast into an optical semiconductor lead frame (InGaN element, 3.5 mm × 2.8 mm) shown in FIG. 1, and then in an oven (resin curing oven) at 120 ° C. By heating for 5 hours, an optical semiconductor device in which the optical semiconductor element was sealed with the cured product of the curable epoxy resin composition was obtained. In FIG. 1, 100 is a reflector (light reflecting resin composition), 101 is a metal wiring, 102 is an optical semiconductor element, 103 is a bonding wire, and 104 is a cured product (sealing material).

Example 4
A curable epoxy resin composition was obtained in the same manner as in Example 2 except that the epoxy curing agent obtained in Production Example 3 was changed to the epoxy curing agent obtained in Production Example 4. Moreover, the optical semiconductor device was obtained like Example 1 using this curable epoxy resin composition.

Comparative Examples 1 and 2
A curable epoxy resin composition was obtained in the same manner as in Example 1 except that the composition of the epoxy resin was changed to the composition shown in Table 1. Moreover, the optical semiconductor device was obtained like Example 1 using this curable epoxy resin composition.

Comparative Example 3
A curable epoxy resin composition was obtained in the same manner as in Example 2 except that the epoxy curing agent obtained in Production Example 3 was changed to the epoxy curing agent obtained in Production Example 5. Moreover, the optical semiconductor device was obtained like Example 1 using this curable epoxy resin composition.

Comparative Example 4
A curable epoxy resin composition was obtained in the same manner as in Example 2 except that the epoxy curing agent obtained in Production Example 3 was changed to the epoxy curing agent obtained in Production Example 6. Moreover, the optical semiconductor device was obtained like Example 1 using this curable epoxy resin composition.

Comparative Example 5
A curable epoxy resin composition was obtained in the same manner as in Example 2 except that the epoxy curing agent obtained in Production Example 3 was changed to the epoxy curing agent obtained in Production Example 7. Moreover, the optical semiconductor device was obtained like Example 1 using this curable epoxy resin composition.

Comparative Example 6
A curable epoxy resin composition was obtained in the same manner as in Example 2 except that the epoxy curing agent obtained in Production Example 3 was changed to the epoxy curing agent obtained in Production Example 8. Moreover, the optical semiconductor device was obtained like Example 1 using this curable epoxy resin composition.

<Evaluation>
The following evaluation tests were carried out on the optical semiconductor devices obtained in the examples and comparative examples.

[Curing coloring test]
The degree of coloring of the sealing material portion (cured product) of the optical semiconductor device obtained in Examples and Comparative Examples was visually confirmed and evaluated with the following indices. The results are shown in the column of “Curing Coloring Test [Visual]” in Table 1.
◎ (Coloring at the time of curing is highly suppressed): Sealing material portion is colorless ○ (Coloring at the time of curing is suppressed): Sealing material portion is slightly yellow △ (Coloring at the time of curing is clear) ): Sealing material part is yellow × (Coloring during curing is remarkable): Sealing material part is tan

[Solder heat resistance test]
The optical semiconductor devices (two used for each curable epoxy resin composition) obtained in the examples and comparative examples were left to stand for 192 hours under the conditions of 30 ° C. and 60% RH for moisture absorption treatment. Subsequently, the said optical semiconductor device was put into the reflow furnace, and it heat-processed on the following heating conditions. Thereafter, the optical semiconductor device was taken out in a room temperature environment and allowed to cool, and then again placed in a reflow furnace and heat-treated under the same conditions. That is, in the solder heat resistance test, the thermal history under the following heating conditions was given twice to the optical semiconductor device.
[Heating conditions (based on surface temperature of optical semiconductor device)]
(1) Preheating: 150 to 190 ° C. for 60 to 120 seconds (2) Main heating after preheating: 217 ° C. or more for 60 to 150 seconds, maximum temperature 260 ° C.
However, the rate of temperature increase when shifting from preheating to main heating was controlled to 3 ° C./second at the maximum.
FIG. 2 shows an example of a surface temperature profile (temperature profile in one of the two heat treatments) of the optical semiconductor device when heated by the reflow furnace.
The coloring degree of the sealing material portion (cured product) of the optical semiconductor device subjected to the two heat treatments was visually confirmed and evaluated with the same index as in the curing coloring test. The results are shown in the column of “Solder Heat Resistance Test [Visual]” in Table 1. In addition, when there was a difference in coloring degree between two optical semiconductor devices, the result of the more colored one was shown.
Furthermore, the optical semiconductor device was observed using a digital microscope (trade name “VHX-900”, manufactured by Keyence Corporation), and electrode peeling (peeling of the cured product from the electrode surface) was performed by two heat treatments. It was confirmed whether it occurred. Of the two optical semiconductor devices, the number of optical semiconductor devices in which electrode peeling occurred is shown in the column of “Solder heat resistance test [number of electrode peelings]” in Table 1.

[Thermal shock test]
The optical semiconductor devices obtained in Examples and Comparative Examples (two used for each curable epoxy resin composition) were exposed in an atmosphere of −40 ° C. for 30 minutes, and then in an atmosphere of 100 ° C. A thermal shock with one cycle of exposure to 30 minutes was applied for 200 cycles using a thermal shock tester. Thereafter, a current of 10 mA was passed through the optical semiconductor device, and the number of optical semiconductor devices that were not lit (unlit optical semiconductor device) was measured. It has been confirmed that all optical semiconductor devices are lit before the thermal shock test. The results are shown in the column of “Thermal Shock Test [No. of Lights]” in Table 1.

[Comprehensive judgment]
As a result of each test, the case where all of the following (1) to (4) were satisfied was judged as ◯ (good). On the other hand, when any of the following (1) to (4) was not satisfied, it was determined as x (defective).
(1) Curing color test: the sealing material portion of the optical semiconductor device is colorless (◎) after the test (2) Solder heat resistance test: the sealing material portion of the optical semiconductor device is colorless (◎) or after the test Slightly yellow (○) (3) Solder heat resistance test: No. of optical semiconductor devices with electrode peeling (4) Thermal shock test: No. of non-lighted optical semiconductor devices 1 is shown in the column “Overall judgment”.

The description of the components listed in Table 1 is shown below.
YD-128: trade name “YD-128” [bisphenol A type epoxy resin], manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. Celoxide 2021P: trade name “Celoxide 2021P” [3,4-epoxycyclohexylmethyl (3,4 Epoxy) cyclohexane carboxylate], manufactured by Daicel Corporation MH-700: trade name "Licacid MH-700" [4-methylhexahydrophthalic anhydride / hexahydrophthalic anhydride = 70/30], Shin Nippon Rika Co., Ltd. Manufactured ethylene glycol: Wako Pure Chemical Industries, Ltd. PX-4MP: Trade name “Hishicolin PX-4MP” [Methyltri-n-butylphosphonium dimethyl phosphate], Nippon Chemical Industry Co., Ltd. U-CAT 18X: Trade name “U -CAT 18X "[Amine-based curing accelerator], manufactured by San Apro Co., Ltd.

Test equipment ・ Resin curing oven ESPH Co., Ltd. GPH-201
・ Thermal shock tester Espec Co., Ltd. Small thermal shock device TSE-11-A
-Reflow furnace UNI-5016F manufactured by Nippon Antom Co., Ltd.

100: Reflector (resin composition for light reflection)
DESCRIPTION OF SYMBOLS 101: Metal wiring 102: Optical semiconductor element 103: Bonding wire 104: Hardened | cured material (sealing material)

Claims (5)

An epoxy compound (A), an acid anhydride curing agent (B), and a quaternary phosphonium salt curing accelerator (C),
As epoxy compound (A), bisphenol A type epoxy resin 30 to 90% by weight and alicyclic epoxy compound 10 to 70% by weight with respect to the total amount (100% by weight) of epoxy compound (A),
As a quaternary phosphonium salt-based curing accelerator (C), the following formula (1)

[In formula, R < ¹ > is the same or different, and shows a C1-C10 alkyl group or an aryl group. R ² represents an alkyl group having 1 to 4 carbon atoms. X ⁻ represents a conjugate base of an organic sulfonic acid. ]
And a compound (C-1) represented by the following formula (2)

[In formula, R < ³ > is the same or different, and shows a C1-C10 alkyl group or an aryl group. R ⁴ represents an alkyl group having 1 to 4 carbon atoms. Z ⁻ represents a conjugate base of an acidic phosphate ester. ]
The curable epoxy resin composition characterized by including the compound (C-2) represented by these.   The curable epoxy resin composition according to claim 1, wherein the acid anhydride curing agent (B) is a non-aromatic acid anhydride curing agent. Hardened | cured material of the curable epoxy resin composition of Claim 1 or 2. It is a resin composition for optical semiconductor sealing, The curable epoxy resin composition of Claim 1 or 2 .   An optical semiconductor device in which an optical semiconductor element is sealed with a cured product of the curable epoxy resin composition according to claim 4.

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