JP6072138B2 - Method for producing cured product and cured product - Google Patents

Description

  The present invention relates to a method for producing a cured product, a cured product, a sealing material including the cured product, and an optical semiconductor device including the sealing material.

  A resin used for an optical semiconductor device, particularly a sealing material for an optical semiconductor, is required to have high light transmittance, luminous intensity retention, and excellent crack resistance in a heat cycle test. Conventionally, according to the alicyclic epoxy resin, high light transmittance and luminous intensity retention were realized, but there was a problem that cracks were likely to occur in the heat cycle test. In order to solve this problem, a curing catalyst is used to divide the curing temperature into several stages and the curing proceeds in stages, or an alicyclic epoxy resin and a bisphenol A type epoxy resin having an aromatic ring are mixed. The method is taken. However, in the former method, workability is poor and sufficient crack resistance cannot be obtained, and in the latter method, there is a drawback in that the luminous intensity retention is reduced due to the aromatic ring.

  Patent Document 1 includes an alicyclic epoxy resin and 2,2-bis (hydroxymethyl) containing a curing catalyst and comprising 3,4-epoxycyclohexenylmethyl-3 ′, 4′-epoxycyclohexenecarboxylate as an epoxy resin. It includes both alicyclic epoxy resins composed of 1,2-epoxy-4- (2-oxiranyl) cyclohexane adduct of -1-butanol and at least one of the compounds represented by the following formula (A) or (B) Is a cured product obtained by curing a composition containing 0.01% by mass to 1% by mass with respect to the total mass of the translucent sealing material. This cured product is cured at 120 ° C. for 1 hour and then at 150 ° C. for 1 hour, and has poor crack resistance.

  Patent Document 2 describes an epoxy resin obtained by thermosetting bisphenol A diglycidyl ether as an epoxy resin using an acid anhydride curing agent and a curing accelerator. In Patent Document 2, when it is desired to reduce the internal stress of the cured product, it is precured at about 80 ° C. to 130 ° C. for about 0.5 hours to 5 hours, and then about 0.1 ° C. at about 130 ° C. to 180 ° C. There is a description that it is preferable to perform post-curing under conditions of about 1 hour to 15 hours. In the examples, after curing at 120 ° C. for 1 hour, a cured product is created by post-curing at 150 ° C. for 3 hours. However, under such conditions, the obtained cured product has poor crack resistance. In the case of the epoxy resin having a thickness of 5 mm, the yellow index after heat treatment at 150 ° C. for 5 days is increased by 15.2, and thermal yellowing is observed.

Japanese Patent No. 4366934 JP 2008-179733 A

An object of the present invention is a cured product that is excellent in transparency, light resistance (lightness retention, etc.) and excellent in crack resistance in a heat cycle test, and is suitable for, for example, a sealing material for an optical semiconductor device. It is to provide a method for curing an object.
Another object of the present invention is to provide a cured product which is cured by the curing method and has excellent transparency and light resistance and excellent crack resistance in a heat cycle test.
Another object of the present invention is to provide a sealing material and an optical semiconductor device, which contain the cured product, which are excellent in transparency and light resistance and excellent in crack resistance in a heat cycle test.

  As a result of intensive studies to solve the above problems, the present inventors have determined that the alicyclic epoxy compound is 60% by weight or more based on the total amount of the curable component, a curing agent such as an acid anhydride, and a curing accelerator. When the curable resin composition is cured by a specific curing method, a cured product, a sealing material, and an optical semiconductor device that are excellent in transparency and light resistance and crack resistance in a heat cycle test are obtained. The present invention has been found.

That is, this invention contains an alicyclic epoxy compound (A), a hardening | curing agent (B), and a hardening accelerator (C) as a sclerosing | hardenable component, and content of this alicyclic epoxy compound (A) is included. Curing the curable epoxy resin composition containing 60% by weight or more of the curable component and including the compound having a hydroxyl group under curing conditions of a temperature of 95 ° C. or more and 135 ° C. or less and 4.5 hours or more. Provided is a method for producing a cured product.
Further, the present invention provides a compound in which the alicyclic epoxy compound (A) has (i) an epoxy group composed of two adjacent carbon atoms and oxygen atoms constituting the alicyclic ring, and / or (ii) ) A method for producing a cured product which is a compound in which an epoxy group is directly bonded to an alicyclic ring by a single bond.
In the present invention, the curing accelerator (C) is 1,8-diazabicyclo [5.4.0] undecene-7 (DBU), and a salt thereof, 1,5-diazabicyclo [4.3.0]. Provided is a method for producing a cured product which is at least one compound selected from nonene-5 (DBN) and salts thereof, tertiary amines, imidazoles, phosphines, phosphonium compounds, organometallic salts and metal chelates.
Moreover, this invention provides the hardened | cured material manufactured with the manufacturing method of the said hardened | cured material.
Moreover, this invention provides the sealing material containing the said hardened | cured material.
Furthermore, this invention provides the optical semiconductor device containing the said sealing material.

  According to the method for producing a cured product of the present invention, by optimizing the temperature and time under curing conditions, the transparency is excellent, for example, when used as a sealing material for an optical semiconductor device, light resistance, heat cycle test A cured product, a sealing material, and a semiconductor device excellent in crack resistance can be obtained.

<Method for producing cured product>
The manufacturing method of the hardened | cured material of this invention contains an alicyclic epoxy compound (A), a hardening | curing agent (B), and a hardening accelerator (C) as a sclerosing | hardenable component, and this alicyclic epoxy compound (A). A curable epoxy resin composition having a content of 60% by weight or more based on the total amount of the curable component is cured under curing conditions of a temperature of 95 ° C. or more and 135 ° C. or less and 4.5 hours or more.

<Curing conditions>
In the method for producing a cured product of the present invention, the curable epoxy resin composition is cured under curing conditions of a temperature of 95 ° C. or more and 135 ° C. or less and 4.5 hours or more. In the present specification, curing can be performed by placing the curable epoxy resin composition at a predetermined temperature for a predetermined time, for example, without putting it in a predetermined mold. Curing may be performed continuously for a predetermined time without an interval, or may be taken in the middle. When taking an interval, the curing time indicates a total time of curing times processed at a predetermined temperature before and after the interval.

  The curing temperature is 95 ° C or higher and 135 ° C or lower, preferably 100 ° C or higher and lower than 130 ° C, and more preferably 100 ° C or higher and 120 ° C or lower. The curing temperature may be in the above temperature range, and may be constant or several different temperatures. The interval refers to the time when the temperature is lower than 95 ° C., and may be near room temperature (for example, about 25 ° C.). In this interval, the curable epoxy resin composition may be removed from the mold, and the curable epoxy resin composition removed from the mold may be further cured at the curing temperature. The curing temperature may be constant or may vary within a temperature range of 95 ° C to 135 ° C. In particular, the curing temperature is preferably constant regardless of the presence or absence of an interval.

  The curing time is 4.5 hours or more (for example, 4.5 hours or more and 24 hours or less), preferably 5 hours or more and 20 hours or less, more preferably 5 hours or more and 16 hours or less. The interval can be 30 minutes or longer (for example, 30 minutes to 30 days). The interval is preferably 30 minutes to 10 days, more preferably 30 minutes to 3 days. In the case of taking an interval, for example, the curable epoxy resin composition is put into a predetermined mold, cured at a predetermined temperature for 1 to 2 hours, and then the curable epoxy resin composition is allowed to cool to near room temperature, and then from the mold. Removal and subsequent curing at the predetermined temperature for the remaining time. In the manufacturing method of the hardened | cured material of this invention, the hardened | cured material excellent in the crack resistance in a heat cycle test is obtained by hardening | curing a curable epoxy resin composition on said hardening conditions.

<Curable epoxy resin composition>
The curable epoxy resin composition used in the method for producing a cured product of the present invention includes an alicyclic epoxy compound (A), a curing agent (B), and a curing accelerator (C) as a curable component, Content of this alicyclic epoxy compound (A) is 60 weight% or more with respect to curable component whole quantity.

<Alicyclic epoxy compound (A)>
The alicyclic epoxy compound (A) used in the present invention is not particularly limited as long as it is a compound having an aliphatic ring. (I) Consists of two adjacent carbon atoms and oxygen atoms constituting the alicyclic ring. The compound having an epoxy group and (ii) a compound in which the epoxy group is directly bonded to the alicyclic ring by a single bond are preferable.

  (I) The compound having an epoxy group composed of two adjacent carbon atoms and oxygen atoms constituting the alicyclic ring can be arbitrarily selected from well-known ones. As the alicyclic epoxy group, a cyclohexene oxide group is preferable.

式（Ｉ）中、Ｘは連結基（１以上の原子を有する２価の基）を示し、例えば、単結合、２価の炭化水素基、カルボニル基、エーテル結合、エステル結合、カーボネート基、アミド基、及びこれらが複数個連結した基等が挙げられる。 (I) Especially as a compound which has an epoxy group comprised by two adjacent carbon atoms and oxygen atoms which comprise an alicyclic ring, the fat represented by the following formula (I) in terms of transparency and heat resistance A cyclic epoxy resin is desirable.

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

  As a 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 methylene, methylmethylene, dimethylmethylene, ethylene, propylene, and trimethylene groups. Examples of the divalent alicyclic hydrocarbon group include 1,2-cyclopentylene, 1,3-cyclopentylene, cyclopentylidene, 1,2-cyclohexylene, 1,3-cyclohexylene, 1, And divalent cycloalkylene groups (including cycloalkylidene groups) such as 4-cyclohexylene and cyclohexylidene groups.

  As the linking group X, a linking group containing an oxygen atom is preferable. Specifically, —CO—, —O—CO—O—, —COO—, —O—, —CONH—; A group in which one or two of these groups are linked to one or more of divalent hydrocarbon groups, and the like. Examples of the divalent hydrocarbon group include the aforementioned groups.

  Representative examples of the alicyclic epoxy compound represented by the formula (I) include compounds represented by the following formulas (I-1) to (I-8). For example, commercially available products such as Celoxide 2021P and Celoxide 2081 (manufactured by Daicel Chemical Industries) can also be used. In addition, in the following formula, l and m represent the integer of 1-30. R is an alkylene group having 1 to 8 carbon atoms, and linear or branched alkylene groups such as methylene, ethylene, propylene, isopropylene, butylene, isobutylene, s-butylene, pentylene, hexylene, heptylene, and octylene groups are included. Can be mentioned. Among these, a linear or branched alkylene group having 1 to 3 carbon atoms such as methylene, ethylene, propylene, and isopropylene group is preferable.

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

式（ＩＩ）中、Ｒ'はｐ価のアルコールからｐ個の−ＯＨを除した基；ｐ、ｎは自然数を表す。ｐ価のアルコール［Ｒ'−(ＯＨ)_p］としては、２，２−ビス（ヒドロキシメチル）−１−ブタノール等の多価アルコールなど（炭素数１〜１５のアルコール等）が挙げられる。ｐは１〜６が好ましく、ｎは１〜３０が好ましい。ｐが２以上の場合、それぞれの（ ）内の基におけるｎは同一でもよく異なっていてもよい。上記化合物としては、具体的には、２，２−ビス（ヒドロキシメチル）−１−ブタノールの１，２−エポキシ−４−（２−オキシラニル）シクロヘキサン付加物、ＥＨＰＥ ３１５０（ダイセル化学工業製）などが挙げられる。

In the formula (II), R ′ is a group obtained by removing p —OH from a p-valent alcohol; 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 (such as 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 may be the same or different. Specific examples of the compound include 1,2-epoxy-4- (2-oxiranyl) cyclohexane adduct of 2,2-bis (hydroxymethyl) -1-butanol, EHPE 3150 (manufactured by Daicel Chemical Industries), and the like. Is mentioned.

  As the alicyclic epoxy compound (A), the above-exemplified compounds can be used singly or in combination of two or more kinds, such as Celoxide 2021P, Celoxide 2081, EHPE 3150 (manufactured by Daicel Chemical Industries), etc. Commercial products can be preferably used.

  Content of an alicyclic epoxy compound (A) is 60 weight% or more (for example, 60-100 weight%) with respect to the curable component whole quantity contained in a curable epoxy resin composition. The curable component is a curable compound that is cured by heat or radiation. The content of the alicyclic epoxy compound (A) is preferably 70% by weight (70 to 100% by weight), more preferably 80% by weight or more (80 to 100% by weight) with respect to the total amount of the curable component. can do. In addition, the said content is content of the sum total, when using 2 or more types of alicyclic epoxy compounds (A). By setting the content of the alicyclic epoxy compound (A) in the above range, when the curable epoxy resin composition is cured, a cured product having excellent light transmittance and luminous intensity retention is obtained.

  The total content of the curable components in the curable epoxy resin composition used in the method for producing a cured product of the present invention is, for example, 30 to 90% by weight, preferably 40 to 80% by weight, and more preferably 40 to 70% by weight. It is. By setting the content of the curable component in the curable epoxy resin composition within the above range, a resin composition having excellent curability can be obtained.

<Curable components other than alicyclic epoxy compound (A)>
The curable epoxy resin composition used in the present invention may contain an epoxy compound other than the alicyclic epoxy compound (A). Epoxy compounds other than the alicyclic epoxy compound (A) include dioctyl epoxyhexahydrophthalate, bis (2-ethylhexyl) epoxyhexahydrophthalate, 1,4-butanediol diglycidyl ether, 1,6-hexanediol. Diglycidyl ether, glycerin triglycidyl ether, trimethylolpropane triglycidyl ether, sorbitol tetraglycidyl ether, dipentaerythritol hexaglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, propylene glycol, glycerin Polyethers of polyether polyols obtained by adding one or more alkylene oxides to aliphatic polyhydric alcohols such as Ricidyl ether, monoglycidyl ether of aliphatic long-chain dibasic aliphatic higher alcohol, phenol, cresol, butylphenol, polyether glycol monoglycidyl ether obtained by adding alkylene oxide to these, glycidyl ester of higher fatty acid Epoxidized soybean oil, octyl epoxy stearate, butyl epoxy stearate, epoxidized linseed oil, epoxidized polybutadiene, ethylene oxide, propylene oxide, styrene oxide, methyl glycidyl ether, butyl glycidyl ether, allyl glycidyl ether, phenyl glycidyl ether, Ethylene glycol glycidyl phenyl ether, ethylene glycol benzyl glycidyl ether, diethylene glycol Glycidyl tetrahydropyranyl ether, glycidyl methacrylate, glycidyl acetate, etc., or it may be used in which some or all of the hydrogen atoms of these epoxy compounds are substituted with fluorine.

  In addition to the above, an oligomer-type radiation curable resin having an epoxy group inside can also be used. Examples thereof include epoxidized polybutadiene (product names: Epolide PB3600, PB4700, Daicel Chemical Industries, Ltd.), epoxidized styrene butadiene teleblock copolymer (product names Epofriend AT501, Daicel Chemical Industries, Ltd.), and the like. Also obtained by reacting novolak-type epoxy resins such as phenols, cresols, halogenated phenols and alkylphenols with phenols and formaldehyde in the presence of an acidic catalyst with epichlorohydrin and / or methyl epichlorohydrin. (Product names: EOCN-103, EOCN-104S, EOCN-1020, EOCN-1027, EPPN-201, BREN-S, Nippon Kayaku Co., Ltd., product names: DEN-431, DEN-439, Dow Chemical And product names: N-73, VH-4150, Dainippon Ink and Chemicals, Inc.). Also, a bisphenol type epoxy resin obtained by reacting bisphenols such as bisphenol A, bisphenol F, bisphenol S and tetrabromobisphenol A with epichlorohydrin, or a condensate of diglycidyl ether of bisphenol A and the bisphenols and epichlorohydrin. And bisphenol type epoxy resins (product names: Epicoat 1004, Epicoat 1002, Yuka Shell Co., Ltd., product names: DER-330, DER-337, Dow Chemical Co.).

  As an epoxy compound other than the alicyclic epoxy compound (A), the above-exemplified compounds can be used alone or in combination of two or more. As an epoxy compound other than the alicyclic epoxy compound (A), an epoxy compound having an aromatic ring such as a bisphenol A type epoxy resin can be preferably used. Epoxy compounds other than the alicyclic epoxy compound (A) may not be used.

<Curing agent (B)>
The curable epoxy resin composition used in the method for producing a cured product of the present invention contains a curing agent (B). The curing agent (B) has a function of curing the compound having an epoxy group. As the curing agent (B) in the present invention, a conventionally known curing agent can be used as a curing agent for epoxy resin. In particular, the curing agent (B) in the present invention is preferably an acid anhydride that is liquid at 25 ° C., and examples thereof include methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, dodecenyl succinic anhydride, and methyl endo. And methylenetetrahydrophthalic anhydride. Also, for example, acid anhydrides that are solid at room temperature (25 ° C.), such as phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylcyclohexene dicarboxylic acid anhydride, are liquid acid anhydrides at room temperature (25 ° C.) It can be used as the curing agent (B) in the present invention by dissolving in a product to form a liquid mixture. In the present invention, as the curing agent (B), commercially available products such as RIKACID MH-700 (manufactured by Nippon Nippon Chemical Co., Ltd.) and HN-5500 (manufactured by Hitachi Chemical) can also be used.

  The curing agent (B) may be used singly or as a mixture of two or more kinds in an arbitrary ratio. The amount of use is, for example, 50 to 150 parts by weight, preferably 100 to 145 parts by weight, more specifically, with respect to 100 parts by weight of the total amount of compounds having an epoxy group contained in the curable epoxy resin composition. Is preferably used at a ratio of 0.5 to 1.5 equivalents per 1 equivalent of epoxy groups in the compound having all epoxy groups contained in the curable epoxy resin composition. When the amount of the curing agent (B) used is less than 50 parts by weight, the effect becomes insufficient and the toughness of the cured product tends to be reduced, while the amount of the curing agent (B) used exceeds 150 parts by weight. When the cured product is colored, the hue may deteriorate. In addition, the said usage-amount is the usage-amount of the sum total, when using 2 or more types of hardening | curing agents (B).

  In the present invention, the curing agent (B) is preferably used at a ratio of 0.5 to 1.5 equivalents per 1 equivalent of epoxy groups in the compound having all epoxy groups contained in the curable epoxy resin composition. Because it is used, there are many reaction points at the time of curing, and since the curable epoxy resin composition is cured at a low temperature of 95 ° C. or more and 135 ° C. or less, the curing proceeds gently and uniformly, and the heat cycle test It is considered that a cured product having excellent crack resistance is produced.

<Curing accelerator (C)>
The curable epoxy resin composition used in the method for producing a cured product of the present invention contains a curing accelerator (C). A hardening accelerator (C) is a compound which has a function which accelerates | stimulates a cure rate, when the compound which has an epoxy group hardens | cures with a hardening | curing agent. As the curing accelerator (C) that may be contained in the curable epoxy resin composition of the present invention, a well-known and commonly used curing accelerator can be used. For example, 1,8-diazabicyclo [5.4. 0] undecene-7 (DBU), and salts thereof (eg, phenol salt, octylate, p-toluenesulfonate, formate, tetraphenylborate); 1,5-diazabicyclo [4.3.0] Nonene-5 (DBN) and its salts (for example, phosphonium salt, sulfonium salt, quaternary ammonium salt, iodonium salt); benzyldimethylamine, 2,4,6-tris (dimethylaminomethyl) phenol, N, N- Tertiary amines such as dimethylcyclohexylamine; 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole Phosphines such as phosphate ester and triphenylphosphine; phosphonium compounds such as tetraphenylphosphonium tetra (p-tolyl) borate; organometallic salts such as tin octylate and zinc octylate; metal chelates and the like . These can be used alone or in admixture of two or more.

  In the present invention, as the curing accelerator (C), U-CAT SA 506, U-CAT SA 102, U-CAT 5003, U-CAT 18X, 12XD (developed product) (all manufactured by San-Apro), TPP Commercially available products such as -K, TPP-MK (both manufactured by Hokuko Chemical Co., Ltd.) and PX-4ET (manufactured by Nippon Chemical Industry Co., Ltd.) can also be used.

  The curing accelerator (C) may be used singly or in combination of two or more in any ratio. The amount of use is, for example, 0.05 to 5 parts by weight, preferably 0.1 to 3 parts by weight, with respect to 100 parts by weight of the total amount of compounds having an epoxy group contained in the curable epoxy resin composition. The amount is particularly preferably 0.2 to 3 parts by weight, and most preferably about 0.25 to 2.5 parts by weight. When the amount of the curing accelerator (C) used is less than 0.05 parts by weight, the curing acceleration effect may be insufficient. On the other hand, when the amount of the curing accelerator (C) used exceeds 5 parts by weight, The cured product may be colored to deteriorate the hue. In addition, the said usage-amount is the usage-amount of the sum total, when using 2 or more types of hardening accelerators (C).

<Inorganic filler>
The curable epoxy resin composition used in the method for producing a cured product of the present invention may further contain an inorganic filler. The inorganic filler is not particularly limited, but silica, alumina, mica, synthetic mica, talc, calcium oxide, calcium carbonate, zirconium oxide, titanium oxide, barium titanate, kaolin, bentonite, diatomaceous earth, boron nitride, nitriding One or more kinds of aluminum, silicon carbide, zinc oxide, cerium oxide, cesium oxide, magnesium oxide, glass beads, glass fiber, graphite, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, cellulose and the like can be used. Examples of the inorganic filler include nano silica, nano titania, nano zirconia, and carbon nanotube.

These inorganic fillers can be produced by a known method such as a flame hydrolysis method, a flame pyrolysis method, or a plasma method described in, for example, International Publication No. 96/31572. As preferred inorganic fillers, stabilized colloidal inorganic particle nano-dispersed sols and the like can be used, and commercially available products include BAYER silica sol, Goldschmidt SnO ₂ sol, MERCK Commercially available products such as TiO ₂ sols, SiO ₂ , ZrO ₂ , A1 ₂ O ₃ and Sb ₂ O ₃ sols from Nissan Chemicals or Aerosil dispersions from DEGUSSA are available.

  Inorganic fillers can change their viscosity behavior by surface modification. The surface modification of the particles can be performed using a known surface modifier. As such a surface modifier, for example, a compound capable of interacting with a functional group present on the surface of the inorganic filler such as a covalent bond or complex formation, or a compound capable of interacting with a polymer matrix may be used. it can. Examples of such surface modifiers include carboxyl groups, (primary, secondary, and tertiary) amino groups, quaternary ammonium groups, carbonyl groups, glycidyl groups, vinyl groups, ) A compound having a functional group such as acryloxy group or mercapto group can be used. Such a surface modifier is usually a liquid under standard temperature and pressure conditions, and is composed of a low molecular organic compound having a carbon number in the molecule of, for example, 15 or less, preferably 10 or less, particularly preferably 8 or less. Is done. The molecular weight of the low molecular weight organic compound is, for example, 500 or less, preferably 350 or less, particularly 200 or less.

Preferred surface modifiers include, for example, formic acid, acetic acid, propionic acid, butyric acid, pentanoic acid, hexanoic acid, acrylic acid, methacrylic acid, crotonic acid, citric acid, adipic acid, succinic acid, glutaric acid, oxalic acid, malein acid and saturated or unsaturated mono- and polycarboxylic acids having 1 to 12 carbon atoms such as fumaric acid (preferably monocarboxylic acids); and C ₁ -C ₄ alkyl esters of these esters (preferably such as methyl methacrylate Amides; β-dicarbonyl compounds such as acetylacetone, 2,4-hexanedione, 3,5-heptanedione, acetoacetic acid and C ₁ -C ₄ alkylacetoacetic acids. Moreover, although it does not specifically limit, a well-known and usual silane coupling agent can also be used as a surface modifier.

  The particle size of the inorganic filler is usually about 0.01 nm to 200 μm, preferably 0.1 nm to 100 μm, and particularly about 0.1 nm to 50 μm.

  The content of the inorganic filler is preferably 1 to 2000 parts by weight, and more preferably 10 to 1000 parts by weight, where the total content of the curable components is 100 parts by weight. Moreover, content of the inorganic filler with respect to the whole quantity of a curable epoxy resin composition is 5-95 wt%, for example, Preferably it is 10-90 wt%. In addition, the said content is content of the sum total, when using 2 or more types of inorganic fillers.

<Rubber particles>
The curable epoxy resin composition used in the present invention may contain rubber particles. Examples of the rubber particles include particulate NBR (acrylonitrile-butadiene rubber), reactive terminal carboxyl group NBR (CTBN), metal-free NBR, particulate SBR (styrene-butadiene rubber), and the like. The rubber particle has a multilayer structure (core-shell structure) composed of a core portion having rubber elasticity and at least one shell layer covering the core portion, and a functional group capable of reacting with an alicyclic epoxy resin on the surface. Rubber particles having a hydroxyl group and / or a carboxyl group, an average particle diameter of 10 nm to 500 nm, and a maximum particle diameter of 50 nm to 1000 nm, wherein the refractive index of the rubber particles and the curable epoxy resin composition It may be a rubber particle having a difference from the refractive index of the cured product within ± 0.02. The rubber particles may be used singly or in combination of two or more in any ratio. The content of the rubber particles is, for example, 0.5 to 30 parts by weight, preferably 1 to 20 parts by weight, and more preferably 1 to 10 parts by weight with respect to 100 parts by weight of the curable component. If the blending amount is less than 0.5 parts by weight, the crack resistance tends to decrease, and if it exceeds 30 parts by weight, the heat resistance and transparency tend to decrease. In addition, the said content is content of the sum total, when using 2 or more types of rubber particles.

<Additives>
In addition to the above, the curable epoxy resin composition according to the present invention can use various additives within a range not impairing the effects of the present invention. For example, when a compound having a hydroxyl group such as ethylene glycol, diethylene glycol, propylene glycol, or glycerin is used as the additive, the reaction can be allowed to proceed slowly. In addition, as long as viscosity and transparency are not impaired, silicone-based and fluorine-based antifoaming agents, leveling agents, silane coupling agents such as γ-glycidoxypropyltrimethoxysilane, surfactants, flame retardants, Conventional additives such as a colorant, an antioxidant, an ultraviolet absorber, an ion adsorbent, a pigment, a phosphor, and a release agent can be used.

  The curable epoxy resin composition used in the method for producing a cured product of the present invention can be obtained by uniformly mixing the above components. In order to obtain the curable epoxy resin composition, each component is made as uniform as possible by using generally known mixing equipment such as a revolving type stirring and defoaming device, a homogenizer, a planetary mixer, a three-roll mill, and a bead mill. It is desirable to perform stirring, dissolution, mixing, dispersion, etc.

<Hardened product>
In the present invention, by curing the curable epoxy resin composition under the above-mentioned curing conditions, it is excellent in transparency and light resistance (such as light intensity retention) and various physical properties such as crack resistance in a heat cycle test. Cured product is obtained.

<Encapsulant>
The encapsulant of the present invention uses the curable epoxy resin composition as an encapsulant and is cured under the above-mentioned curing conditions, so that it has excellent transparency and light resistance (such as light intensity retention) and a heat cycle. Excellent physical properties such as crack resistance in the test.

<Optical semiconductor device>
The optical semiconductor device of the present invention is obtained by sealing an optical semiconductor element with the curable epoxy resin composition and curing it under the curing conditions described above. The optical semiconductor element is sealed by injecting the curable epoxy resin composition prepared by the above-described method into a predetermined mold and heat-curing under the above-described curing conditions. The optical semiconductor device of the present invention is excellent in transparency and light resistance (such as light intensity retention), and is excellent in various physical properties such as crack resistance in a heat cycle test.

  According to the method for producing a cured product of the present invention, an optical semiconductor encapsulant, an adhesive, excellent in transparency, light resistance (such as light intensity retention), and various physical properties such as crack resistance in a heat cycle test, Electrical insulating material, laminated board, coating, ink, paint, sealant, resist, composite material, transparent substrate, transparent sheet, transparent film, optical element, optical lens, optical member, stereolithography, electronic paper, touch panel, solar cell base An optical waveguide, a light guide plate, a holographic memory, and the like are obtained.

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples. Examples 6 and 7 are described as reference examples.

Production Example 1
(Epoxy resin A agent)
1,2-epoxy-4- (2-oxyral) cyclohexane adduct of 2,2-bis (hydroxymethyl) -1-butanol (EHPE 3150, manufactured by Daicel Chemical Industries) and 3,4-epoxycyclohexylmethyl-3 ′, 4 '-Epoxycyclohexanecarboxylate (Celoxide 2021P manufactured by Daicel Chemical Industries) or bisphenol A type epoxy resin (YD-128 manufactured by Nippon Steel Chemical Co., Ltd.) was mixed according to the formulation (unit: parts by weight) shown in Table 1, By stirring for 1 hour, 1,2-epoxy-4- (2-oxiranyl) cyclohexane adduct of 2,2-bis (hydroxymethyl) -1-butanol was dissolved to obtain an epoxy resin (mixture).

Production Example 2
(A mixture of curing agent, curing accelerator and additive, flexibility imparting agent, hereinafter referred to as B agent)
As the agent B, a curing agent (Rikacid MH-700 manufactured by Shin Nippon Chemical Co., Ltd .; 4-methylhexahydrophthalic anhydride / hexahydrophthalic anhydride = 70/30): 100 parts by weight, a curing accelerator (manufactured by SANAPRO 18X): 0. 5 parts by weight, additive (ethylene glycol manufactured by Wako Pure Chemical Industries): 1 part by weight, flexibility imparting agent (Rikacid HF-08, manufactured by Shin Nippon Rika Co., Ltd.): 3 parts by weight Taro AR-250 manufactured by Shinky Co., Ltd.) was used to uniformly mix and defoam to obtain B agent.

Examples 1-7, Comparative Examples 1-7
According to the compounding formulation (unit: parts by weight) shown in Table 1, the epoxy resin A agent obtained in Production Example 1 and the B agent obtained in Production Example 2 were subjected to a revolutionary stirring device (Awatori Kentaro AR) -250 made by Shinky Co., Ltd.) and uniformly defoamed to obtain a curable epoxy resin composition.

Curing conditions (1)
The resin composition obtained in Examples 1 and 3 was poured into a mold (shape: lamp shape, size: φ3), a lead frame mounted with a blue light emitting diode element was inserted, and then an oven (GPH- manufactured by Espec Corp.) was inserted. 201) was cured by heating at 100 ° C. for 15 hours to obtain an optical semiconductor device in which the element was sealed with resin.

Curing conditions (2)
The resin compositions obtained in Examples 2, 4 to 7 were poured into a mold (shape: lamp shape, size: φ3), a lead frame on which a blue light emitting diode element was mounted was inserted, and then an oven (manufactured by Espec Corp.) GPHH-201) was heat-cured at 120 ° C. for 7 hours to obtain an optical semiconductor device in which the element was sealed with resin.

Curing conditions (3)
After injecting the resin composition obtained in Comparative Examples 1 and 4 into a mold (shape: lamp shape, size: φ3) and inserting a lead frame mounted with a blue light-emitting diode element, an oven (GPH- manufactured by Espec Corp.) 201) was cured by heating at 120 ° C. for 4 hours to obtain an optical semiconductor device in which the element was sealed with resin.

Curing conditions (4)
The resin composition obtained in Comparative Examples 2 and 5 to 7 was poured into a mold (shape: lamp shape, size: φ3), and after inserting a lead frame on which a blue light emitting diode element was mounted, an oven (manufactured by Espec Corp.) GPHH-201) was heat-cured at 100 ° C. for 2 hours, and was then heat-cured at 140 ° C. for 3 hours to obtain an optical semiconductor device in which the element was sealed with the cured resin.

Curing conditions (5)
The resin composition obtained in Comparative Example 3 was poured into a mold (shape: lamp shape, size: φ3), a lead frame mounted with a blue light-emitting diode element was inserted, and then an oven (GPHH-201 manufactured by Espec Corp.) The optical semiconductor device in which the element was sealed with a cured resin was obtained by heat curing at 150 ° C. for 7 hours.

Light transmittance The curable epoxy resin composition before curing according to the formulation of Examples and Comparative Examples was cast into a predetermined mold and thermally cured under the above-described curing conditions to produce a plate having a thickness of 3 mm. The light transmittance at 450 nm was measured using a spectrophotometer (Spectrophotometer UV-2450 manufactured by Shimadzu Corporation). The results are shown in Table 1.

Luminance retention rate The total luminous flux of the optical semiconductor devices obtained from the examples and comparative examples was measured using a total luminous flux measuring machine (Multispectral Radiation Measurement System OL771 manufactured by Optronic Laboratories, USA). Further, the total luminous flux after a current of 100 mA was passed through the optical semiconductor device for 300 hours in a constant temperature and humidity chamber at 23 ° C. and 60% RH was measured. The luminous intensity retention was calculated from the following equation. The results are shown in Table 1.
{Luminance retention rate (%)} = {Total luminous flux after 300 hours (lm)} / {Total luminous flux after 0 hours (lm)} × 100

Crack resistance test The thermal shock with a cycle of −40 ° C. for 15 minutes and 120 ° C. for 15 minutes was applied to the optical semiconductor devices obtained from the examples and comparative examples, using a thermal shock tester (compact cold thermal shock device TSE-11). 400 cycles were tested using -A manufactured by ESPEC Corporation. Thereafter, the length of the crack is observed using a digital microscope (VHX-900, manufactured by Keyence), and the number of optical semiconductor devices having a crack length of 90 μm or more among the five optical semiconductor devices. Was measured. The results are shown in Table 1.

Claims (2)

It contains an alicyclic epoxy compound (A), a curing agent (B), and a curing accelerator (C) as a curable component, and the alicyclic epoxy compound (A) constitutes (i) an alicyclic ring. A compound having an epoxy group composed of two adjacent carbon atoms and an oxygen atom, and / or (ii) a compound in which an epoxy group is directly bonded to an alicyclic ring by a single bond, and the alicyclic epoxy compound A curable epoxy resin composition containing at least one compound selected from the group consisting of ethylene glycol, diethylene glycol, propylene glycol, and glycerin, wherein the content of (A) is 80 % by weight or more based on the total amount of the curable component A method for producing a cured product, comprising curing a product under curing conditions of a temperature of 95 ° C. or higher and 120 ° C. or lower and 4.5 hours or longer. The curing accelerator (C) is 1,8-diazabicyclo [5.4.0] undecene-7 (DBU) and a salt thereof, 1,5-diazabicyclo [4.3.0] nonene-5 (DBN). , and salts thereof, tertiary amine, imidazole, phosphines, phosphonium compounds, the process according to claim 1 cured product according at least one compound selected from organic metal salts and metal chelates.