JP2010121105A - Curable resin composition and optical member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a curable resin composition, whose cured product having high optical transparency and excellent in heat resistance and mounting reliability, and an optical member using the same. <P>SOLUTION: The curable resin composition contains (A) a urethane oligomer, (B) a polymerizable compound having at least one unsaturated double bond, (C) a radical polymerization initiator, and (D) a hindered amine-based light stabilizer. The urethane oligomer (A) is obtained by reacting (a) a diisocyanate compound with (b) a polycaprolactonediol or a polycarbonatediol and (c) a hydroxy group-containing (meth)acrylate or a caprolactone-modified (meth)acrylate. An equivalent ratio of an isocyanate group in the component (a) to a hydroxy group in the component (b) and the component (c) is 0.8 to 1.2. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention provides a curable resin composition having high optical transparency of the cured product and excellent heat resistance and mounting reliability, and a transparent substrate, lens, adhesive, optical waveguide and light emitting diode (LED) using the same. The present invention relates to an optical member for use in an optical semiconductor device such as a phototransistor, a photodiode, or a solid-state imaging device.

  Conventionally, acrylic resins that are excellent in transparency and light resistance, such as PMMA (polymethyl methacrylate resin), have been widely used as optical member resins. However, PMMA has a problem that heat resistance is insufficient because it is a thermoplastic resin having a large cure shrinkage.

  On the other hand, the resin for optical members used in the field of optical / electronic equipment is required to have a mounting process on an electronic substrate and the like, heat resistance and mechanical characteristics under high temperature operation, and epoxy resin is often used. However, in recent years, the use of high-intensity laser light, blue light, and near-ultraviolet light has expanded in the field of optical and electronic equipment, and a resin that is more excellent in transparency, heat resistance, and light resistance than ever is required.

  In general, epoxy resins have high transparency in the visible range, but sufficient transparency cannot be obtained in the ultraviolet to near ultraviolet range. Among them, epoxy resins using alicyclic bisphenol A diglycidyl ether have relatively high transparency, but have problems such as being easily colored by heat and light.

  On the other hand, Patent Documents 1 and 2 disclose methods for reducing impurities that are one of the causes of coloring contained in alicyclic bisphenol A diglycidyl ether.

  In recent years, those using a silicone resin excellent in transparency and colorability for optical member applications, for example, those described in Patent Document 3, have been disclosed.

JP 2003-171439 A JP 2004-75894 A JP 2004-2810 A

  However, there is room for improvement in heat resistance, mounting reliability, and the like for epoxy resins whose impurities are reduced by the methods described in Patent Documents 1 and 2 and the like. In addition, the silicone resin described in Patent Document 3 is generally concerned with problems such as difficulty in handling, a large linear expansion coefficient, and low adhesion.

  Therefore, an object of the present invention is to provide a curable resin composition having high optical transparency of the cured product and excellent in heat resistance and mounting reliability, and an optical member using the same.

（式中、Ｒは、炭素数１〜１０の直鎖または分岐鎖の炭化水素基であり、ｍ，ｎは、１〜５０の整数である。）

（式中、Ｒ_１またはＲ_２は、炭素数１〜１０の直鎖または分岐鎖の炭化水素基であり、ｎは、１〜５０の整数である。）

（式中、Ｒ_３は、水素またはメチル基であり、Ｒ_４は、炭素数１〜１０の直鎖または分岐鎖の炭化水素基である。）

（式中、Ｒ_５は、水素またはメチル基であり、ｎは、１〜５０の整数である。） The present invention contains (A) a urethane oligomer, (B) a polymerizable compound having at least one unsaturated double bond, (C) a radical polymerization initiator, and (D) a hindered amine light stabilizer. The (A) urethane oligomer is represented by (a) a diisocyanate compound and (b) a polycaprolactone diol represented by the following general formula (1) or the following general formula (2): Urethane oligomer obtained by reacting polycarbonate diol represented by (c) hydroxyl group-containing (meth) acrylate represented by general formula (3) or caprolactone-modified (meth) acrylate represented by general formula (4) The equivalent ratio of isocyanate group (NCO) in component (a) to hydroxyl group (OH) in component (b) and component (c) (NCO / OH) Providing a curable resin composition is 0.8 to 1.2.

(In the formula, R is a linear or branched hydrocarbon group having 1 to 10 carbon atoms, and m and n are integers of 1 to 50.)

(In the formula, R ₁ or R ₂ is a linear or branched hydrocarbon group having 1 to 10 carbon atoms, and n is an integer of 1 to 50.)

(Wherein R ₃ is hydrogen or a methyl group, and R ₄ is a linear or branched hydrocarbon group having 1 to 10 carbon atoms.)

(In the formula, R ₅ is hydrogen or a methyl group, and n is an integer of 1 to 50.)

  According to such a curable resin composition, the cured product has high optical transparency, and is excellent in heat resistance and mounting reliability. The reason why such an effect is obtained by the curable resin composition of the present invention is not necessarily clear, but the present inventors have reduced the curing shrinkage by using the (A) urethane oligomer, and the urethane bond. Toughness is improved by (A) heat resistance is improved by using polycaprolactone diol or polycarbonate diol as a raw material for urethane oligomer, and (D) heat resistance and light resistance are by using a hindered amine light stabilizer. This is thought to be due to the improvement of the properties.

The average weight molecular weight Mw of the (A) urethane oligomer is preferably 2,000 to 20,000.
The mass ratio of the (A) urethane oligomer and the (B) polymerizable compound having at least one unsaturated double bond is preferably 1: 9 to 9: 1.
The content of the (C) radical polymerization initiator is 0.01 with respect to 100 parts by mass of the total amount of the (A) urethane oligomer and the (B) polymerizable compound having at least one unsaturated double bond. It is preferably ˜5 parts by mass.

The content of the (D) hindered amine light stabilizer is 0. 0 parts by mass with respect to 100 parts by mass of the total amount of the (A) urethane oligomer and the (B) polymerizable compound having at least one unsaturated double bond. It is preferable that it is 001-5 mass parts.
The polymerizable compound (B) having at least one unsaturated double bond is one or more polymerizable compounds selected from the group consisting of 2-hydroxyethyl acrylate, tetrahydrofurfuryl acrylate and lauryl acrylate. It is preferable.

  The present invention also provides an optical member obtained by curing the curable resin composition of the present invention. According to such an optical member, since the curable resin composition of the present invention is used, the optical transparency is high, and the heat resistance and the mounting reliability are excellent.

  ADVANTAGE OF THE INVENTION According to this invention, the optical transparency of the cured | curing material is high, and can provide the curable resin composition excellent in heat resistance and mounting reliability, and an optical member using the same.

It is a schematic cross section which shows the specific example of the surface mount type LED package using the curable resin composition of this invention.

  Hereinafter, preferred embodiments of the present invention will be described in detail, but the present invention is not limited to the following embodiments. In the present specification, the (meth) acrylic copolymer means an acrylic copolymer and a methacrylic copolymer corresponding thereto, and the (meth) acrylate means an acrylate and a corresponding methacrylate.

The curable resin composition of the present invention comprises (A) a urethane oligomer, (B) a polymerizable compound having at least one unsaturated double bond, (C) a radical polymerization initiator, and (D) a hindered amine light. And a stabilizer.
Here, (A) urethane oligomer includes (a) a diisocyanate compound, (b) a polycaprolactone diol represented by the following general formula (1) or a polycarbonate diol represented by the following general formula (2), and (c ) A urethane oligomer obtained by reacting a hydroxyl group-containing (meth) acrylate represented by the following general formula (3) or a caprolactone-modified (meth) acrylate represented by the following general formula (4).

（式中、Ｒは、炭素数１〜１０の直鎖または分岐鎖の炭化水素基であり、ｍ，ｎは、１〜５０の整数である。）

(In the formula, R is a linear or branched hydrocarbon group having 1 to 10 carbon atoms, and m and n are integers of 1 to 50.)

（式中、Ｒ_１またはＲ_２は、炭素数１〜１０の直鎖または分岐鎖の炭化水素基であり、ｎは、１〜５０の整数である。）

(In the formula, R ₁ or R ₂ is a linear or branched hydrocarbon group having 1 to 10 carbon atoms, and n is an integer of 1 to 50.)

（式中、Ｒ_３は、水素またはメチル基であり、Ｒ_４は、炭素数１〜１０の直鎖または分岐鎖の炭化水素基である。）

(Wherein R ₃ is hydrogen or a methyl group, and R ₄ is a linear or branched hydrocarbon group having 1 to 10 carbon atoms.)

（式中、Ｒ_５は、水素またはメチル基であり、ｎは、１〜５０の整数である。）

(In the formula, R ₅ is hydrogen or a methyl group, and n is an integer of 1 to 50.)

  The (a) diisocyanate compound is a compound having two isocyanate groups in one molecule. Specific examples thereof include tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, tetramethyl. Examples include xylene diisocyanate, isophorone diisocyanate, norbornane diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated diphenylmethane diisocyanate, and the like. These may be used alone or in combination. Among these, isophorone diisocyanate, norbornane diisocyanate, hydrogenated xylylene diisocyanate, and hydrogenated diphenylmethane diisocyanate are preferable because the resulting urethane oligomer has good yellowness and handling properties.

  Examples of the polycaprolactone diol represented by the general formula (1) include polycaprolactone diol having an average weight molecular weight of 530 (trade name Plaxel 205 manufactured by Daicel Chemical Industries) and polycaprolactone diol having an average weight molecular weight of 830 (Daicel Chemical). Product name Plaxel 208), polycaprolactone diol having an average weight molecular weight of 1,000 (trade name Plaxel 210 made by Daicel Chemical Industries), polycaprolactone diol having an average weight molecular weight of 2,000 (trade name Plaxel 220 made by Daicel Chemical Industries) ), Polycaprolactone diol having an average weight molecular weight of 3,000 (trade name Plaxel 230 manufactured by Daicel Chemical Industries), and polycaprolactone diol having an average weight molecular weight of 4,000 (trade name Plaxel 240 manufactured by Daicel Chemical Industries). And the like. These may be used alone or in combination. Among these, since the handleability of the obtained urethane oligomer is good, a polycaprolactone diol having an average weight molecular weight of 530 (trade name Plaxel 205 manufactured by Daicel Chemical Industries) and a polycaprolactone diol having an average weight molecular weight of 830 (Daicel Chemical). The product brand name Plaxel 208) and polycaprolactone diol having an average weight molecular weight of 1,000 (trade name Plaxel 210, manufactured by Daicel Chemical Industries, Ltd.) are preferable.

  Examples of the polycarbonate diol represented by the general formula (2) include a polycarbonate diol having an average weight molecular weight of 500 (trade name Plaxel CD CD205 manufactured by Daicel Chemical Industries) and a polycarbonate diol having an average weight molecular weight of 1,000 (Daicel Chemical). And a polycarbonate diol having an average weight molecular weight of 2,000 (trade name Plaxel CD CD220 manufactured by Daicel Chemical Industries). These may be used alone or in combination. Among these, since the handling property of the obtained urethane oligomer is good, a polycarbonate diol having an average weight molecular weight of 500 (trade name Plaxel CD CD205 manufactured by Daicel Chemical Industries) and a polycarbonate diol having an average weight molecular weight of 1,000 (Daicel) Chemical brand name Plaxel CD CD210) is preferred.

  Examples of the hydroxyl group-containing (meth) acrylate represented by the general formula (3) include 2-hydroxyethyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, and 2-hydroxypropyl (meth) acrylate. It is done. These may be used alone or in combination.

  The caprolactone-modified (meth) acrylate compound represented by the general formula (4) is an unsaturated fatty acid hydroxyalkyl ester-modified ε-caprolactone in which one (meth) acrylic double bond having radical polymerization property is introduced into a polycaprolactone oligomer. For example, 1 mol addition product of hydroxyethyl (meth) acrylate, 2 mol addition product of hydroxyethyl (meth) acrylate, 3 mol addition product of hydroxyethyl (meth) acrylate, 5 mol addition product of hydroxymele (meth) acrylate, hydroxyethyl (meth) An acrylate 10 mol addition product etc. are mentioned. These may be used alone or in combination. Among these, a hydroxyethyl (meth) acrylate 2 mol addition product and a hydroxyethyl (meth) acrylate 3 mol addition product are more preferable. Moreover, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, etc. can also be used as (meth) acrylate added to polycaprolactone.

  The equivalent ratio of the isocyanate group in the (a) diisocyanate compound to the hydroxyl group in the component (b) and the component (c) is 0.8 to 1.2.

  In addition, when the (A) urethane oligomer is synthesized, a known polymerization inhibitor or catalyst can be added in addition to the above raw material components.

The average weight molecular weight Mw of the (A) urethane oligomer is preferably in the range of 2,000 to 20,000, more preferably in the range of 4,000 to 18,000, and 6,000 to 16,6,000. A range of 000 is particularly preferred. When the average weight molecular weight is less than 2,000, sufficient toughness tends to be hardly obtained, and when it exceeds 20,000, the compatibility with the polymerizable compound (B) having at least one unsaturated double bond is increased. Tend to get worse. In the present specification, “average weight molecular weight” is measured by gel permeation chromatography (GPC) using a standard polystyrene calibration curve, and the measurement conditions are as follows.
<GPC conditions>
Equipment used: Hitachi L-6000 (Hitachi, Ltd.)
Column: Gel pack GL-R420 + Gel pack GL-R430 + Gel pack GL-R440 (3 in total) [all trade names manufactured by Hitachi Chemical Co., Ltd.]
Eluent: Tetrahydrofuran Measurement temperature: 40 ° C
Flow rate: 1.75 ml / min.
Detector: L-3300RI [Hitachi, Ltd.]

  An example of the synthesis method of the above (A) urethane oligomer is shown below. First, an agitator, a thermometer, a cooling pipe, and an air gas introduction pipe are attached to a three-necked flask, and air gas is introduced. Thereafter, (b) polycaprolactone diol or polycarbonate diol, (c) hydroxyl group-containing (meth) acrylate or caprolactone-modified (meth) acrylate, and optionally, a polymerization inhibitor and a catalyst are added in an appropriate amount. While stirring at ˜75 ° C., (a) the diisocyanate compound is uniformly added dropwise to carry out the reaction. After completion of the dropwise addition, it is confirmed by IR measurement that the isocyanate has disappeared, and the reaction is terminated to obtain (A) a urethane oligomer.

  As the polymerization inhibitor, a known polymerization inhibitor can be used, and examples thereof include p-methoxyquinone, p-methoxyphenol, pt-butylcatechol and the like. Moreover, as a catalyst, the well-known catalyst used for urethane oligomer synthesis | combination can be used, For example, dibutyltin dilaurate, dibutyltin diacetate, triethylenediamine, etc. are mentioned.

  In addition, when synthesizing the urethane oligomer (A), a mercaptan compound, thioglycol, carbon tetrachloride, α-methylstyrene dimer, or the like can be added as necessary as a molecular weight modifier.

  The polymerizable compound (B) having at least one unsaturated double bond is a monomer that can be cured by heat or light irradiation, and has no ether structure from the viewpoint of heat resistance. From the viewpoint, those not containing two or more aromatic rings are preferred. Specific examples thereof include glycidyl (meth) acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate glycidyl ether, methyl (meth) acrylate, ethyl (meth) acrylate, and n-propyl. (Meth) acrylate, t-butyl (meth) acrylate, isobutyl (meth) acrylate, ethylhexyl (meth) acrylate, stearyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, ethoxyethyl (meth) acrylate, Butoxyethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-methoxy Toxyl (meth) acrylate, 2-ethoxyethoxy (meth) acrylate, pyrenoxide adduct (meth) acrylate, octafluoropentyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl ( (Meth) acrylate, cyclohexyl mono (meth) acrylate, mono (meth) acrylate having tricyclodecane, ethylene glycol di (meth) acrylate, methanediol di (meth) acrylate, 1,2-ethanediol di (meth) acrylate, 1,3-butanediol di (meth) acrylate, 1,3-propanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,5-pentanediol di (meth) acrylate, 1, 6- Xanthdiol di (meth) acrylate, 1,7-heptanediol di (meth) acrylate, 1,8-octanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, 1,10-decanediol Di (meth) acrylate, 2-butyl-2-ethyl-1,3-propanediol di (meth) acrylate, 3-methyl-1,5-pentanediol di (meth) acrylate, neopentyl di (meth) acrylate, dimethylol Bifunctional (meth) acrylate such as tricyclodecane di (meth) acrylate, zinc di (meth) acrylate, 2- (meth) acryloyloxyethyl acid phosphate, caprolactone-modified tricyclodecane dimethanol di (meth) acrylate, piece Terminal (meth) acrylic modified series A corn oil, a both-ends (meth) acryl modified silicone oil, etc. are mentioned, These can be used individually or in combination of 2 or more types. Among these, 2-hydroxyethyl acrylate, tetrahydrofurfuryl acrylate, and lauryl acrylate are preferable.

(C) As the radical polymerization initiator, a radical thermal polymerization initiator or a photopolymerization initiator can be used.
As the radical thermal polymerization initiator, any one that can be used for ordinary radical polymerization, such as an azo initiator and a peroxide initiator, can be used. Examples of the azo initiator include azobisisobutyronitrile, azobis-4-methoxy-2,4-dimethylvaleronitrile, azobiscyclohexanone-1-carbonitrile, azodibenzoyl, and the like. Examples of peroxide initiators include benzoyl peroxide, lauroyl peroxide, di-t-butylperoxyhexahydroterephthalate, t-butylperoxy-2-ethylhexanoate, 1,1-t-butylperoxide. Examples include oxy-3,3,5-trimethylcyclohexane, t-butylperoxyisopropyl carbonate, and di-t-hexyl peroxide.

  The photopolymerization initiator is not particularly specified as long as it efficiently absorbs and activates the ultraviolet rays of an industrial UV irradiation apparatus and does not yellow the cured resin. Specific examples thereof include 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2-hydroxy-methyl-1-phenyl-propan-1-one, oligo (2- Hydroxy-2-methyl-1- (4- (1-methylvinyl) phenyl) propanone, oligo (2-hydroxy-2-methyl-1- (4- (1-methylvinyl) phenyl) propanone and tripropylene glycol di Mixtures with acrylates and oxy-phenyl-acetic acid 2- (2-oxo-2-phenyl-acetoxy-ethoxy) -ethyl ester and oxy-phenyl-acetic acid 2- (2-hydroxy-ethoxy) -ethyl Examples thereof include a mixture with an ester.

  As the (D) hindered amine light stabilizer, which is also called HALS, for example, tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) 1,2,3, 4-butanetetracarboxylate (manufactured by ADEKA, trade name ADK STAB LA-52), tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) butane-1,2,3,4-butanetetracarboxylate Rate (manufactured by ADEKA, trade name ADK STAB LA-57), 1,2,2,6,6-pentamethyl-4-piperidyl, and tridecyl-1,2,3,4-butanetetracarboxylate (manufactured by ADEKA, Trade name ADK STAB LA-62), 2,2,6,6-tetramethyl-piperidinol, tridecyl alcohol and 1,2,3,4-butante Condensate with lacarboxylic acid (manufactured by ADEKA, trade name ADK STAB LA-67), 1,2,3,4-butanetetracarboxylic acid and 2,2,6,6-tetramethyl-4-piperidinol and β, β , Β, β-tetramethyl-3,9- (2,4,8,10-tetraoxaspiro [5,5] undecane) -diethanol (product of ADEKA, trade name ADK STAB LA-68LD), Decandioic acid bis (2,2,6,6-tetramethyl-4-piperidyl) (manufactured by ADEKA, trade name ADK STAB LA-77Y), 1,2,2,6,6-pentamethyl-4-piperidyl methacrylate ( ADEKA, trade name ADK STAB LA-82), 2,2,6,6-tetramethyl-4-piperidyl methacrylate (ADEKA, trade name ADK STAB L -87), high molecular weight hindered amine light stabilizers (trade name CHIMASSORB 119FL, CHIMASSORB 2020FDL, manufactured by Ciba Specialty Chemicals), poly [{6- (1,1,3,3-tetramethylbutyl) amino- 1,3,5-triazine-2,4-diyl} {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetramethyl-4- Piperidyl) imino}] (Ciba Specialty Chemicals, trade name CHIMASSORB 944FDL), polymer sterically hindered amine derivative (Ciba Specialty Chemicals, trade name TINUVIN 622LD), (Bis (1, 2, 2 , 6,6-pentamethyl-4-piperidyl) [[3,5-bis (1,1- Methylethyl) -4-hydroxyphenyl] methyl] butyl malonate (Ciba Specialty Chemicals, trade name TINUVIN 144), methyl 1,2,2,6,6-pentamethyl-4-piperidyl sebacate (Ciba Specialty) -Chemicals make, brand name TINUVIN 765) etc. are mentioned, These can be used individually or in combination of 2 or more types. Among these, tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) 1,2,3,4-butanetetracarboxylate (manufactured by ADEKA, as a material that remarkably improves heat resistance and light resistance) Trade name ADK STAB LA-52), bis (2,2,6,6-tetramethyl-4-piperidyl) decanedioate (trade name ADK STAB LA-77Y, manufactured by ADEKA), methyl 1,2,2,6 6-pentamethyl-4-piperidyl sebacate (manufactured by Ciba Specialty Chemicals, trade name TINUVIN 765) is preferred.

  The mass ratio of the component (A) and the component (B) in the curable resin composition is preferably in the range of 1: 9 to 9: 1, and preferably in the range of 2: 8 to 8: 2. Is more preferable. When the blending ratio of the component (B) is less than 10 parts by weight with respect to 90 parts by weight of the component (A), the viscosity of the curable resin composition tends to be too high and difficult to handle. When it is larger than 90 parts by mass with respect to 10 parts by mass of the component, the mounting reliability tends to decrease.

  The content of the component (C) in the curable resin composition is preferably 0.01 to 5 parts by mass with respect to 100 parts by mass of the total amount of the component (A) and the component (B). 1 part by mass is particularly preferable. If this content exceeds 5 parts by mass, the cured product tends to be colored by heat or near ultraviolet rays, and if it is less than 0.01 parts by mass, it tends to be difficult to cure. When a plurality of thermal radical polymerization initiators having different half-life temperatures are used, the total content falls within the above range.

  The content of the component (D) in the curable resin composition is preferably 0.001 to 5 parts by mass with respect to 100 parts by mass of the total amount of the components (A) and (B), and 0.01 to It is more preferable to set it as 1 mass part, and it is especially preferable to set it as 0.1-1 mass part. When this content exceeds 5 parts by mass, the cured product tends to be colored, and when it is less than 0.001 part by mass, the effect of suppressing coloring tends to be small.

  In addition to the above components, phenolic or phosphorus antioxidants, ultraviolet absorbers, inorganic fillers, organic fillers, coupling agents, polymerization inhibitors, etc., should be added to the curable resin composition. Can do. Moreover, a mold release agent, a plasticizer, an antistatic agent, a flame retardant, etc. may be added from the viewpoint of moldability.

  In the method for producing an optical member using the present curable resin composition, a resin solution is poured into a desired part, poured into a potting, or poured into a mold and cured by heating. Further, it is desirable to reduce the oxygen concentration in the curable resin composition in advance by nitrogen bubbling in order to inhibit curing and prevent coloring. As the curing conditions in the case of thermosetting, the temperature and time at which the curing is finally completed are desirable. (B) Although it depends on the type, combination and addition amount of the components, it is preferably about 1 to 5 hours at 60 to 150 ° C. Moreover, in order to reduce the internal stress generated by the rapid curing reaction, it is desirable to raise the curing temperature stepwise.

  As the package molded body when the present curable resin composition is applied to the transparent sealing resin of the surface-mounted LED package, a thermoplastic resin and a thermosetting resin can be applied. As the thermoplastic resin, any conventionally known thermoplastic resin such as a liquid crystal polymer, a polyphthalamide resin, or polybutylene terephthalate can be used. As the thermosetting resin, various resins such as an epoxy resin, a silicone resin, a urethane resin, and a cyanate resin can be used. In particular, an epoxy resin is preferable because of its excellent adhesion to the transparent sealing resin. When a thermoplastic resin is used, molding is performed by injection molding, and when a thermosetting resin is used, molding is performed by transfer molding.

  As described above, the curable resin composition of the present embodiment described above is a curable resin composition having high optical transparency of the cured product and excellent heat resistance and mounting reliability, and a transparent substrate using the cured product. , Lenses, adhesives, optical waveguides and light emitting diodes (LEDs), phototransistors, photodiodes, and optical members for use in optical semiconductor elements such as solid-state imaging devices.

FIG. 1 is a schematic cross-sectional view showing a specific example of a surface-mounted LED package using the curable resin composition of the present invention. A surface mount LED package 200 shown in FIG. 1 includes a semiconductor light emitting element 102, a sealing body (transparent sealing resin) 104 made of a cured product obtained by curing the curable resin composition of the present invention, a resin molded body 100, and the like. Have
The resin molded body 100 has a structure in which a pair of leads 105 and 106 molded from a lead frame are molded with a resin portion 103 made of a thermosetting resin.
An opening 101 is formed in the resin portion 103, and the semiconductor light emitting element 102 is placed therein. And it is sealed with the sealing body 104 so that the semiconductor light emitting element 102 may be included. The semiconductor light emitting element 102 is mounted on the lead 106.
The electrode 102 a on the semiconductor light emitting element 102 and the lead 105 are connected by a wire 107. When power is supplied to the semiconductor light emitting element 102 through the two leads 105 and 106, light emission occurs, and the light emission is extracted from the light extraction surface 108 through the sealing body 104.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the scope of the present invention is not limited thereto.

(Production Example 1)
A stirrer, a thermometer, a cooling tube and an air gas introduction tube were attached to a 2 L three-necked flask, and after introducing air gas, 795.0 g of polycaprolactone diol having an average weight molecular weight of 530 (trade name Plaxel 205, manufactured by Daicel Chemical Industries), 69.6 g of 2-hydroxyethyl acrylate (Kyoeisha Co., Ltd., trade name Light Ester HOA), 0.5 g of p-methoxyquinone (manufactured by Wako Pure Chemical Industries, Ltd.) as a polymerization inhibitor, and dibutylthitin dilaurate as a catalyst (Tokyo Fine Chemical Co., Ltd.) Company-made, product name L101) 0.3 g was added, heated to 70 ° C., and then stirred with 70-75 ° C., 270.0 g of isophorone diisocyanate (product name Desmodur I manufactured by Sumika Bayer Urethane Co., Ltd.) for 2 hours The solution was uniformly dropped over the course of the reaction. When the reaction was completed for about 5 hours after the completion of the dropping, the reaction was terminated after confirming that the isocyanate had disappeared as a result of IR measurement, and urethane oligomer 1 (UA1) having a weight average molecular weight of 7,100 was obtained.

(Production Example 2)
Except for 795.0 g of polycaprolactone diol having an average weight molecular weight of 530, 180.0 g of unsaturated fatty acid hydroxyalkyl ester modified ε-caprolactone (trade name FA2D manufactured by Daicel Chemical Industries, Ltd.), and 270.0 g of isophorone diisocyanate. In the same manner as in Production Example 1, urethane oligomer 2 (UA2) was synthesized. Its weight average molecular weight was 7,000.

(Production Example 3)
Except for 750.0 g of polycarbonate diol having an average weight molecular weight of 500 (trade name Plaxel CD CD205 manufactured by Daicel Chemical Industries), 180.0 g of unsaturated fatty acid hydroxyalkyl ester modified ε-caprolactone, and 270.0 g of isophorone diisocyanate, In the same manner as in Production Example 1, urethane oligomer 3 (UA3) was synthesized. Its weight average molecular weight was 6,100.

(Production Example 4)
Except for 500.0 g of polycarbonate diol having an average weight molecular weight of 500, 120.0 g of unsaturated fatty acid hydroxyalkyl ester modified ε-caprolactone, and 247.0 g of norbornane diisocyanate (trade name COSMONATE NBDI manufactured by Mitsui Chemicals Polyurethanes) In the same manner as in Production Example 1, urethane oligomer 4 (UA4) was synthesized. Its weight average molecular weight was 7,000.

(Production Example 5)
575.0 g of polycarbonate diol having an average weight molecular weight of 500, 138.0 g of unsaturated fatty acid hydroxyalkyl ester-modified ε-caprolactone, and 268.0 g of hydrogenated xylylene diisocyanate (trade name TAKENATE 600 manufactured by Mitsui Chemicals Polyurethanes). Except that, urethane oligomer 5 (UA5) was synthesized in the same manner as in Production Example 1. Its weight average molecular weight was 7,100.

(Production Example 6)
The above production example except that polycaprolactone diol (trade name Plaxel 210, manufactured by Daicel Chemical Industries, Ltd.) having an average molecular weight of 1,000 was 780.0 g, 2-hydroxyethyl acrylate was 30.0 g, and isophorone diisocyanate was 137.0 g. In the same manner as in 1, urethane oligomer 6 (UA6) was synthesized. Its weight average molecular weight was 8,900.

(Production Example 7)
Urethane oligomer 7 (UA7) was prepared in the same manner as in Production Example 1 except that 0 g of polycaprolactone diol or polycarbonate diol, 600.0 g of unsaturated fatty acid hydroxyalkyl ester-modified ε-caprolactone and 150.0 g of isophorone diisocyanate were used. Synthesized. Its weight average molecular weight was 700.

(Examples 1-10 and Comparative Examples 1-2)
The components shown in Table 1 were mixed at room temperature (25 ° C.) to prepare each resin composition of Examples 1 to 10 and Comparative Examples 1 and 2. This resin composition has a cross-section of the structure shown in FIG. 1, a mold having dimensions of 20 mm × 20 mm × 1 mm, a polyphthalate having an outer dimension of 3.2 mm × 2.6 mm × 1.8 mm, and a cavity inner diameter of Φ2.4 mm. Pour into the cavity (opening) of the amide surface-mount LED package with a pipetter and heat in an oven in a nitrogen atmosphere with an oxygen concentration of 500 ppm or less for 3 hours at 60 ° C and for 1 hour at 120 ° C. Got. Also, a 1 mm thick silicone spacer was poured into a mold sandwiched between glass plates, and heated in an oven at 60 ° C. for 3 hours and 120 ° C. for 1 hour to obtain a 1 mm thick cured product.

※表中の配合量数値単位は全て質量部
ＵＡ１、ＵＡ２、ＵＡ３、ＵＡ４、ＵＡ５、ＵＡ６、ＵＡ７：ウレタンオリゴマー１、２、３、４、５、６、７
ＨＥＡ：２−ヒドロキシエチルアクリレート（共栄社株式会社製 商品名ライトエステルＨＯＡ）
ＴＨＦＡ：テトラヒドロフルフリルアクリレート（共栄社株式会社製 商品名ライトアクリレートＴＨＦ−Ａ）
ＬＡ：ラウリルアクリレート（共栄社株式会社製 商品名ライトアクリレートＬ−Ａ）
ＭＭＡ：メチルメタクリレート（和光純薬工業株式会社製）
開始剤：過酸化ラウロイル（日本油脂株式会社製 商品名パーロイルＬ）
光安定剤：メチル１，２，２，６，６−ペンタメチル−４−ピペリジルセバケート（チバ・スペシャルティ・ケミカルズ社製、商品名ＴＩＮＵＶＩＮ ７６５）

* All numerical values in the table are in mass parts UA1, UA2, UA3, UA4, UA5, UA6, UA7: Urethane oligomers 1, 2, 3, 4, 5, 6, 7
HEA: 2-hydroxyethyl acrylate (trade name Light Ester HOA manufactured by Kyoeisha Co., Ltd.)
THFA: Tetrahydrofurfuryl acrylate (trade name Light acrylate THF-A manufactured by Kyoeisha Co., Ltd.)
LA: Lauryl acrylate (trade name Light Acrylate LA, manufactured by Kyoeisha Co., Ltd.)
MMA: Methyl methacrylate (Wako Pure Chemical Industries, Ltd.)
Initiator: Lauroyl peroxide (trade name Parroyl L, manufactured by NOF Corporation)
Light stabilizer: Methyl 1,2,2,6,6-pentamethyl-4-piperidyl sebacate (manufactured by Ciba Specialty Chemicals, trade name TINUVIN 765)

The mounting reliability of the surface mount LED packages obtained in the above examples and comparative examples and the optical properties of the cured product were measured by the following methods.
The mounting reliability of the surface-mount type LED package is as follows. Each resin composition in the package is subjected to a thermal temperature cycle (one cycle is set to −40 ° C./30 min-85 ° C./30 min, and evaluated at 0 cycles (initial) and 100 cycles). The presence or absence of cracks (cracks) and peeling (defective) between the transparent sealing resin and the package molded body was evaluated. The defective product rate (= number of defects / number of packages used in the test * 100 (%)) in a predetermined number of cycles was calculated and defined as mounting reliability.
The transmittance of the cured product was measured after being cured (initial stage) and after being left at 150 ° C. for 24 hours as an evaluation of heat discoloration. The measurement was performed using a spectrophotometer with a test piece having a thickness of 1 mm.
Table 2 shows the mounting reliability of the surface-mounted LED packages of the above examples and comparative examples, and the optical characteristics of the cured body, that is, the transmittance of light having a wavelength of 500 nm after curing (initial) and after standing at high temperature.

  The surface mount type LED packages of Examples 1 to 10 are all excellent in mounting reliability. Furthermore, it can be seen that the optical properties of the cured body also have a high initial transmittance and a small decrease in the transmittance after being left at a high temperature. On the other hand, in Comparative Example 1 in which polycaprolactone diol or polycarbonate diol was not used during the production of the urethane oligomer, peeling occurred under a cold temperature cycle. Further, in Comparative Example 2 in which (A) the urethane oligomer was not used, peeling occurred under a cold temperature cycle.

  As is clear from the above, the curable resin composition of the present invention has high optical transparency of the cured product, little decrease in transmittance after high-temperature storage, and excellent heat resistance and mounting reliability. It is suitable for optical elements for use in electronic materials such as a sealing resin for optical semiconductors. When the curable resin composition of the present invention is applied to an optical member, the lifetime and reliability of the optical element can be improved due to good heat resistance.

  DESCRIPTION OF SYMBOLS 100 ... Resin molding, 101 ... Opening part, 102 ... Semiconductor light emitting element, 103 ... Resin part, 104 ... Sealing body (transparent sealing resin), 105, 106 ... Lead, 107 ... Wire, 108 ... Light extraction surface, 200: Surface mount type LED package.

Claims (7)

Curing comprising (A) a urethane oligomer, (B) a polymerizable compound having at least one unsaturated double bond, (C) a radical polymerization initiator, and (D) a hindered amine light stabilizer. A functional resin composition comprising:
The (A) urethane oligomer comprises (a) a diisocyanate compound, (b) a polycaprolactone diol represented by the following general formula (1) or a polycarbonate diol represented by the following general formula (2), and (c) It is a urethane oligomer obtained by reacting a hydroxyl group-containing (meth) acrylate represented by the general formula (3) or a caprolactone-modified (meth) acrylate represented by the following general formula (4):
Curable resin composition whose equivalent ratio of the isocyanate group in the said (a) component with respect to the hydroxyl group in the said (b) component and the said (c) component is 0.8-1.2.

(In the formula, R is a linear or branched hydrocarbon group having 1 to 10 carbon atoms, and m and n are integers of 1 to 50.)

(In the formula, R ₁ or R ₂ is a linear or branched hydrocarbon group having 1 to 10 carbon atoms, and n is an integer of 1 to 50.)

(Wherein R ₃ is hydrogen or a methyl group, and R ₄ is a linear or branched hydrocarbon group having 1 to 10 carbon atoms.)

(In the formula, R ₅ is hydrogen or a methyl group, and n is an integer of 1 to 50.)   The curable resin composition according to claim 1, wherein the (A) urethane oligomer has an average weight molecular weight Mw of 2,000 to 20,000.   The curable resin composition according to claim 1 or 2, wherein a mass ratio of (A) the urethane oligomer and (B) a polymerizable compound having at least one unsaturated double bond is 1: 9 to 9: 1. object.   Content of said (C) radical polymerization initiator is 0.01 with respect to 100 mass parts of total amounts of said (A) urethane oligomer and said (B) polymeric compound which has at least one unsaturated double bond. Curable resin composition as described in any one of Claims 1-3 which is -5 mass parts.   The content of the (D) hindered amine light stabilizer is 0.000 part by mass with respect to 100 parts by mass of the total amount of the (A) urethane oligomer and the (B) polymerizable compound having at least one unsaturated double bond. It is 001-5 mass parts, The curable resin composition as described in any one of Claims 1-4.   The polymerizable compound (B) having at least one unsaturated double bond is one or more polymerizable compounds selected from the group consisting of 2-hydroxyethyl acrylate, tetrahydrofurfuryl acrylate and lauryl acrylate. The curable resin composition according to any one of claims 1 to 5.   The optical member formed by hardening | curing the curable resin composition as described in any one of Claims 1-6.

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