JP5251919B2 - Resin composition for optical semiconductor element sealing - Google Patents

Description

The present invention relates to a composition for encapsulating an optical semiconductor element, and in particular, relates to an optical semiconductor element encapsulating composition excellent in heat discoloration and curability, in which a main component is substantially composed of a silicone resin.

  Conventionally, epoxy resin compositions have been widely used to seal optical semiconductor elements. The epoxy resin composition usually contains an alicyclic epoxy resin, a curing agent, and a curing catalyst as main components. The optical semiconductor element is sealed by pouring and curing the composition into a mold in which the optical semiconductor element is disposed by casting, transfer molding, or the like. However, with the brightness and power-up of the LED, discoloration and deterioration of the epoxy resin have become a problem. In particular, since the alicyclic epoxy resin is yellowed by blue light or ultraviolet light, there is a problem of shortening the lifetime of the LED element.

  Then, although the silicone resin excellent in heat resistance and light resistance is used, there exists a problem that the intensity | strength of the hardened resin is weak compared with an epoxy resin. In order to solve this problem, a material using a high-hardness rubber-like silicone resin for sealing has been proposed (Patent Document 1). However, the high-hardness silicone resin has poor adhesion, and in a case-type light-emitting semiconductor device, that is, a device in which a light-emitting element is arranged in a ceramic and / or plastic housing and the inside of the housing is filled with silicone resin, −40 In a thermal shock test at ˜120 ° C., there is a problem that the silicone resin is peeled off from the ceramic or plastic of the housing.

  In order to increase adhesiveness and thermal shock resistance, a silicone resin having an epoxy group has been proposed (Patent Document 2). The silicone resin is synthesized by condensing a silane having an epoxy group and silanol, but the cured product has a low elastic modulus and is brittle. Therefore, the LED sealed with the resin has a problem that the resin is easily cracked in the temperature cycle test.

  As a solution to this problem, an epoxy resin, a composition containing silsesquioxane having at least two epoxy rings (Patent Document 3), and a silicone resin having an epoxy resin and an isocyanuric acid derivative group as a stress reducing agent The composition (patent document 4) containing this is known. However, none of these shows the occurrence of cracks in the temperature cycle test of the cured product, and the thermal shock resistance is not satisfactory.

JP 2002-314143 A Japanese Patent Laid-Open No. 7-97433 JP 2005-263869 A JP 2004-99751 A

An object of the present invention is to provide an optical semiconductor device encapsulating which solves the above-mentioned problems, has a high hardness, is excellent in light resistance and thermal shock resistance, can form a sealing body particularly excellent in heat discoloration, and has improved curing speed and the like. It is providing the resin composition for a stop.

  As a result of various studies, the present inventors have obtained an epoxy-modified silicone resin having a linear polysiloxane structure and two types of organosilanes, which are obtained by condensation and have an epoxy equivalent smaller than that of the epoxy-modified silicone resin. The inventors have found that the above object can be achieved by using two epoxy-modified silicone resins in combination, and have made the present invention.

That is, this invention is a composition for optical semiconductor element sealing containing the following (A), (B), (C) and (D) component.
(A) 50-90 mass parts of 1st silicone resins which have an epoxy-group-containing non-aromatic group represented by the following average compositional formula (1)

(In Formula (1), R ¹ is an epoxy group-containing non-aromatic group, R ² is a group independently selected from a hydroxyl group, a C _1-20 monovalent hydrocarbon group, and a C _1-6 alkoxy group, R ³ Is a C _1-20 monovalent hydrocarbon group,
x and y are each independently an integer of 0, 1 or 2;
a is a number from 0.25 to 0.75,
b is a number from 0.25 to 0.75,
c is a number from 0 to 0.3, where a + b + c = 1,
n is an integer of 2 to 20)
(B) 10-50 mass parts of 2nd silicone resins which have an epoxy-group-containing non-aromatic group represented by the following average compositional formula (2)

(In the formula (2), R ¹ , R ² and R ³ are as described above, z is an integer of 0, 1 or 2 independently of each other;
d is a number from 0.5 to 0.8,
e is a number from 0.2 to 0.5,
(D + e = 1)
(C) Curing agent having functional group reactive with epoxy group (A) The functional group reactive with the epoxy group is 0.4 mol in total for 1 mol of the epoxy group in the component (A) and the component (B). The amount which becomes -1.5 mol (D) Curing catalyst 0.01-3 weight part with respect to a total of 100 mass parts of (A) component and (B) component.

  Since the resin composition of the present invention contains the second silicone resin, it gives a cured product having high hardness. Moreover, since this 2nd silicone resin is rich in reactivity, the optical semiconductor package with favorable heat-resistant color-change property can be given in a short time.

The measurement chart of ²⁹ Si-NMR obtained about the 1st silicone resin obtained in the synthesis example 1 is shown.

<(A) component>
In the composition of the present invention, (A) the first silicone resin having an epoxy group-containing non-aromatic group is represented by the following average composition formula (1).

In the formula (1), n is an integer of 2 to 20, preferably 3 to 20, and more preferably 3 to 10. x and y are each independently an integer of 0, 1 or 2. In each of the first structural unit with the subscript a and the third structural unit with the subscript c constituting the first silicone resin, a unit in which x or y is 0 (T unit) ), A unit in which x or y is 1 (D unit) and a unit in which x or y is 2 (M unit) are usually present together in one molecule. In each of the first structural unit and the third structural unit, the abundance ratio of the T unit, the D unit, and the M unit depends on the type of R ² in the monomer used in the production method described later and the progress of hydrolysis / condensation. To do. The molar ratio of T unit: D unit: M unit is preferably 10:30:60 to 98: 1: 1, more preferably 40:30:30 to 98: 1: 1, and even more preferably 60. : 20: 20 to 96: 2: 2, and still more preferably 80:10:10 to 95: 3: 2.

In the (R ³ ₂ SiO) _n unit in the formula (1), for example, the unit in which n is 3 has the following structure.

The (R ³ ₂ SiO) _n unit may be in the main chain when the silicone resin is linear, or may be bonded to any branch as long as it is branched. By containing the (R ³ ₂ SiO) _n unit, a cured product having excellent thermal shock resistance can be obtained.

In the formula (1), R ¹ is an epoxy group-containing non-aromatic group, for example, an epoxy group-containing linear or branched fat such as a γ-glycidoxyalkyl group such as a γ-glycidoxypropyl group. Epoxy group-containing heterocycle-containing groups such as an epoxy group-containing alicyclic group such as an aromatic group, β- (3,4-epoxycyclohexyl) ethyl group, a monoglycidyl isocyanuryl group and a diglycidyl isocyanuryl group. Can be mentioned. Among these, an epoxy group-containing alicyclic group, particularly a β- (3,4-epoxycyclohexyl) ethyl group is preferable. In addition, although it is possible to use the non-aromatic group which has oxetanyl group instead of an epoxy group, the epoxy group is excellent from a sclerosing | hardenable point. R ¹ is preferably present in at least one, more preferably 2 to 100, in one molecule. Moreover, it is preferable that it exists in the terminal of a molecule | numerator, for example, when a molecular structure is linear, it is more preferable that there is one each at the both ends.

R ² is a group selected from a hydroxyl group, a C _1-20 monovalent hydrocarbon group, and a C _1-6 alkoxy group. Examples of the hydrocarbon group include alkyl groups such as methyl group, ethyl group, propyl group and butyl group, cycloalkyl groups such as cyclopentyl group and cyclohexyl group, aryl groups such as phenyl group, alkaryl groups such as tolyl group, norbonenyl. Examples thereof include a crosslinked cyclic group such as a group. _{Examples of the} C _1-6 alkoxy group include a methoxy group and an ethoxy group. Preferably, R ² is a methyl group or a phenyl group.

R ³ is, independently of each other, a C _1-20 monovalent hydrocarbon group, and the groups described above with respect to R ² are exemplified.

a is a number of 0.25 to 0.75, preferably a number of 0.4 to 0.7. If a is less than the lower limit value, the amount of epoxy groups is small, so the degree of cure of the composition is low, and if it exceeds the upper limit value, the amount of epoxy groups is large, and the synthesized resin gels, which is not preferable. b is a number of 0.25 to 0.75, preferably a number of 0.3 to 0.6. c is a number from 0 to 0.3, preferably a number from 0 to 0.2. When c exceeds the upper limit, the light resistance of the cured product tends to deteriorate. Formula (1) is a composition formula showing the average abundance of each structural unit, and a + b + c = 1.

The component (A) is a linear organopolysiloxane represented by the following formula (3):

(In the above formula, R ³ is as described above, X is a hydrolyzable group such as an alkoxy group and a halogen atom, and m is an integer of 0 to 18).
Following formula (4):

(In the above formula, R ¹ and R ² are as described above, but at least one of R ² is a hydroxyl group or a C _1-6 alkoxy group.)
If necessary, an epoxy group-containing silane represented by formula (5):

(In the above formula, R ² and R ³ are as described above, but at least one of R ² is a hydroxyl group or a C _1-6 alkoxy group.)
It can obtain by carrying out a hydrolysis and a condensation reaction according to a usual method with the silane represented by these.

The component (A) has a polystyrene equivalent weight average molecular weight of 3000 to 10,000, preferably 3000 to 6,000. The epoxy equivalent is 200 to 800 g / mol, preferably 300 to 600 g / mol.

<(B) component>
(B) The second silicone resin having an epoxy group-containing non-aromatic group is represented by the following average composition formula (2).

In the formula (2), R ¹ , R ² and R ³ are as described above. z is an integer of 0, 1 or 2 independently of each other. In the first structural unit to which the subscript d constituting the second silicone resin is attached, a unit in which z is 0 (T unit), a unit in which z is 1 (D unit), and z is 2. A certain unit (M unit) exists together in one molecule. In the structural unit, the abundance ratio of the T unit, the D unit, and the M unit depends on the type of R ² in the monomer used in the production method described later and the degree of progress of hydrolysis / condensation. The molar ratio of T unit: D unit: M unit is preferably 10:30:60 to 98: 1: 1, more preferably 40:30:30 to 98: 1: 1, and even more preferably 60. : 20: 20 to 96: 2: 2, and still more preferably 80:10:10 to 95: 3: 2. d is a number of 0.5 to 0.8, preferably 0.5 to 0.7. When d is less than the lower limit, the composition is poorly cured, and a resin with the upper limit exceeding is difficult to synthesize, and the composition tends to gel, which is not preferable. e is a number from 0.2 to 0.5, preferably from 0.3 to 0.5, where d + e = 1.

The difference between the production method of the component (B) from the production method of the component (A) is represented by R ³ ₂ X ₂ Si instead of the linear organopolysiloxane represented by the general formula (3). The organosilane is prepared by subjecting the organosilane to hydrolysis / condensation reaction with the epoxy group-containing silane represented by the general formula (4). Therefore, the component (B) does not substantially contain the (R ³ ₂ SiO) _n unit contained in the component (A), and acts as a crosslinking point in the cured product to increase the strength of the cured product. Conceivable. Thereby, the composition of the present invention forms a cured product excellent in hardness, thermal shock resistance, etc. without using an epoxy resin, particularly an alicyclic epoxy resin frequently used for sealing an optical semiconductor element. be able to. Since the cured product does not contain such an epoxy resin, there is no discoloration due to heat.

The component (B) has a styrene-equivalent weight average molecular weight of 3000 to 10,000, preferably 3000 to 7000. The epoxy equivalent of (B) component is 100-600 g / mol, Preferably it is 250-400 g / mol. More preferably, the epoxy equivalent of (B) component is about 30-300 g / mol smaller than the epoxy equivalent of (A) component.

(B) The compounding quantity of a component is 10-50 mass parts with respect to a total of 100 mass parts of (A) component and (B) component, Preferably, it is 10-30 mass parts. When the amount of the component (B) exceeds the upper limit, the cured product of the resin composition is likely to be deteriorated by ultraviolet light when the light emitting element emits ultraviolet light. In addition, cracks and the like due to long-term heat tend to occur.

<(C) component>
(C) As a hardening | curing agent, an amine type hardening | curing agent, a phenol type hardening | curing agent, and an acid anhydride type hardening | curing agent are mentioned, Of these, an acid anhydride type hardening | curing agent is preferable.

  Examples of the acid anhydride curing agent include phthalic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, 3-methyl-hexahydrophthalic anhydride, 4-methyl-hexahydrophthalic anhydride, Or a mixture of 3-methyl-hexahydrophthalic anhydride and 4-methyl-hexahydrophthalic anhydride, tetrahydrophthalic anhydride, nadic anhydride, methyl nadic anhydride, norbornane-2,3-dicarboxylic anhydride, methyl norbornane 2,3-dicarboxylic anhydride and the like can be mentioned. The compounding amount of the curing agent is based on a total of 1 mol of the epoxy groups in the component (A) and the component (B) (-CO- in the case of an acid anhydride curing agent). The amount of the acid anhydride group represented by O—CO— is 0.4 to 1.5 mol, and preferably 0.5 to 1.2 mol.

<(D) component>
(D) Curing catalysts include quaternary phosphonium salt-based curing catalysts such as tetrabutylphosphonium / O, O-diethyl phosphorodithioate, tetraphenylphosphonium / tetraphenylborate, triphenylphosphine, diphenylphosphine and the like. Organic phosphine curing catalyst, tertiary amine curing catalyst such as 1,8-diazabicyclo (5,4,0) undecene-7, triethanolamine, benzyldimethylamine, 1,8-diazabicyclo (5,4,0) Undecene-7 phenol salt, 1,8-diazabicyclo (5,4,0) undecene-7 octylate, 1,8-diazabicyclo (5,4,0) undecene-7 toluenesulfonate, etc. Quaternary ammonium salt curing catalyst, 2-methylimidazole, 2-phenyl-4-methyl Imidazole mentioned and imidazole curing catalyst such as, preferably quaternary phosphonium salts, quaternary ammonium salts.

  (D) The compounding quantity of a curing catalyst is 0.01-3 mass parts with respect to a total of 100 mass parts of (A) component and (B) component, Preferably it is 0.05-0.5 mass part. If the amount of the curing catalyst is less than the lower limit, it may not be possible to sufficiently obtain the effect of promoting the reaction between the epoxy resin and the curing agent. On the contrary, if the amount of the curing catalyst is larger than the upper limit value, it may cause discoloration during curing or reflow test.

  In addition to the above components, an antioxidant, an ultraviolet absorber, a deterioration inhibitor, a phosphor for changing wavelength, silica, inorganic fillers such as titanium oxide fine powder, silane, and the like within the scope of the present invention A system coupling agent, a thermoplastic agent, a diluent and the like may be used together as necessary. As the antioxidant, hindered phenol antioxidants and phosphorus antioxidants are preferable. As the ultraviolet absorber, a hindered amine ultraviolet absorber is preferable. As the silane coupling agent, mercapto silane coupling is preferable.

  The composition of the present invention can be easily blended with components (A) to (D) and optionally one or more of the above-mentioned additives and melt-mixed at a temperature at which curing does not proceed at about 60 ° C. Can be manufactured. Melt mixing may be a known method. For example, the above components may be charged into a reactor and melt-mixed in a batch manner, or each of the above components may be charged into a kneader such as a kneader or a heat triple roll. And can be continuously melt-mixed.

  The obtained resin composition for sealing an optical semiconductor element is poured into a mold or case on which a light emitting element is placed in the molten mixture obtained in the above step, and after making a B stage under a predetermined temperature, It can be used after solidifying.

Alternatively, the composition may be applied to a substrate on which an LED is mounted by potting, printing, transfer molding, injection molding, compression molding, or the like. When covering and protecting a light emitting semiconductor device such as an LED by potting or injection, the composition of the present invention is preferably liquid. The viscosity of the resin composition is preferably about 10 to 1,000,000 mPa · s, particularly about 100 to 1,000,000 mPa · s as measured by a rotational viscometer at 25 ° C. On the other hand, when manufacturing a light-emitting semiconductor device by transfer molding or the like, the above-mentioned liquid resin can be used, but the liquid resin is thickened by solidification (B-stage), pelletized, and then molded. Can also be manufactured.

  EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated, this invention is not restrict | limited to the following Example.

[Synthesis of component (A)]
In the following synthesis examples, the average value of n in the average composition formula showing the product is the sum of the products of each n and the peak area at each n in the molecular weight distribution chart by GPC measurement. The value obtained by dividing. For example, when n of a product is an integer of 2 to 20, [2 × (peak area of n = 2) + 3 × (peak area of n = 3) +... + 20 × (peak area of n = 20)] / [(Peak area of n = 2) + (peak area of n = 3) +... + (Peak area of n = 20)]].
<Synthesis Example 1>
MeO (Me) ₂ SiO (Me ₂ SiO) _m Si (Me) ₂ OMe (m is an integer from 0 to 8, average is 1.5) 1695.6 g (5.966 mol) OMe, isopropyl alcohol 3000 ml, 3 -(3,4-epoxycyclohexyl) ethyltrimethoxysilane (KBM303, manufactured by Shin-Etsu Chemical Co., Ltd.) 1470 g (5.966 mol) was charged, and then a 25% tetramethylammonium hydroxide aqueous solution 72 g and water 648 g were added. The mixture was added and stirred at room temperature for 3 hours. After completion of the reaction, 3000 ml of toluene was put into the system. The organic layer was neutralized with an aqueous sodium dihydrogen phosphate solution and separated using a separatory funnel, and washed with hot water. When toluene was removed under reduced pressure, the target resin (resin 1) having a structure represented by the following average composition formula was obtained.

-The weight average molecular weight of polystyrene conversion measured by GPC was 4300. The epoxy equivalent was 403 g / mol.

-The measurement result by ²⁹ Si-NMR is shown in FIG. The peak near -68 ppm reflects Si forming T units, and the peak near -57 to -58 ppm reflects Si forming D units and M units. From this result, it was found that the first structural unit (left unit) constituting the average composition formula contained about 90 mol% of T units and about 10 mol% of D units and M units in total. .

(However, n is an integer of 2 to 10, the average of n is 3.5, and in the first unit, there are those in which x is 0, 1 or 2.)

<Synthesis Example 2>
HO (Me) ₂ SiO [(Me) ₂ SiO] _m Si (Me) ₂ OH (m is an integer of 3 to 18, average is 8) 1500 g (1.975 mol), 3- (3,4-epoxy Cyclohexyl) ethyltrimethoxysilane (KBM303, manufactured by Shin-Etsu Chemical Co., Ltd.) 973.2 g (3.950 mol) and 2300 ml of isopropyl alcohol were added, and then 49.90 g of 25% aqueous solution of tetramethylammonium hydroxide and water 449 were added. .10 g was added and stirred at room temperature for 3 hours. After completion of the reaction, 2300 ml of toluene was put into the system and neutralized with an aqueous sodium dihydrogen phosphate solution. The separated organic layer was washed with hot water using a separatory funnel. When toluene was removed under reduced pressure, a target resin (referred to as “resin 2”) having a structure represented by the following average composition formula was obtained. The weight average molecular weight in terms of polystyrene measured by GPC was 5,600. The epoxy equivalent was 570 g / mol.

(However, n is an integer of 5 to 20, the average of n is 10, and in the first unit, there are those in which x is 0, 1 or 2.)

<Synthesis Example 3>
3-glycidoxypropyltrimethoxysilane (KBM403, manufactured by Shin-Etsu Chemical Co., Ltd. 80) 933.30 g (3.950 mol), HO (Me) ₂ SiO [(Me) ₂ SiO] _m Si (Me) ₂ OH (m is an integer of 3 to 18, average is 8) 1500 g (1.975 mol) and 2300 ml of isopropyl alcohol are charged, and then 92.15 g of a 25% aqueous solution of tetramethylammonium hydroxide and 444.96 g of water are added. And stirred at room temperature for 3 hours. After completion of the reaction, 2300 ml of toluene was put into the system and neutralized with an aqueous sodium dihydrogen phosphate solution. The separated organic layer was washed with hot water using a separatory funnel. When toluene was removed under reduced pressure, a target resin (referred to as “resin 3”) having a structure represented by the following average composition formula was obtained. The weight average molecular weight in terms of polystyrene measured by GPC was 4,300. The epoxy equivalent was 570 g / mol.

(However, n is an integer of 5 to 20, the average of n is 10, and in the first unit, there are those in which x is 0, 1 or 2.)

[Synthesis of component (B)]
<Synthesis Example 4>
Dimethyldimethoxysilane (KBM-22, manufactured by Shin-Etsu Chemical Co., Ltd.) 187.00 g (1.566 mol), 3- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (KBM303, manufactured by Shin-Etsu Chemical Co., Ltd.) ) After adding 766.67 g (3.111 mol) and 900 ml of isopropyl alcohol, 21.69 g of a 25% aqueous solution of tetramethylammonium hydroxide and 195.21 g of water were added and stirred at room temperature for 3 hours. After completion of the reaction, 1000 ml of toluene was put into the system and neutralized with an aqueous sodium dihydrogen phosphate solution. The separated organic layer was washed with hot water using a separatory funnel. When toluene was removed under reduced pressure, a target resin (referred to as “resin 4”) having a structure represented by the following average composition formula was obtained. The weight average molecular weight in terms of polystyrene measured by GPC was 4,200. The epoxy equivalent was 267 g / mol.

(However, in the first unit, there are those in which x is 0, 1 or 2.)

<Synthesis Example 5>
Dimethyldimethoxysilane (KBM-22, manufactured by Shin-Etsu Chemical Co., Ltd.) 187.00 g (1.566 mol), 3- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (KBM303, manufactured by Shin-Etsu Chemical Co., Ltd.) ) After charging 383.33 g (1.566 mol) and 540 ml of isopropyl alcohol, 12.97 g of a 25% aqueous solution of tetramethylammonium hydroxide and 203.93 g of water were added and stirred at room temperature for 3 hours. After completion of the reaction, 1000 ml of toluene was put into the system and neutralized with an aqueous sodium dihydrogen phosphate solution. The separated organic layer was washed with hot water using a separatory funnel. When toluene was added under reduced pressure, the desired resin (referred to as “resin 5”) having a structure represented by the following average composition formula was obtained. The weight average molecular weight in terms of polystyrene measured by GPC was 3,100. The epoxy equivalent was 359 g / mol.

(However, in the first unit, there are those in which x is 0, 1 or 2.)

<Synthesis Example 6>
Dimethyldimethoxysilane (KBM-22, manufactured by Shin-Etsu Chemical Co., Ltd.) 187.00 g (1.566 mol), 3-glycidoxypropyltrimethoxysilane (KBM403, manufactured by Shin-Etsu Chemical Co., Ltd.) 735.24 g ( 3.111 mol) and 900 ml of isopropyl alcohol were added, and 20.98 g of a 25% aqueous solution of tetramethylammonium hydroxide and 188.82 g of water were added and stirred at room temperature for 3 hours. After completion of the reaction, 1000 ml of toluene was put into the system and neutralized with an aqueous sodium dihydrogen phosphate solution. The separated organic layer was washed with hot water using a separatory funnel. When toluene was removed under reduced pressure, a target resin (referred to as “resin 6”) having a structure represented by the following average composition formula was obtained. The weight average molecular weight in terms of polystyrene measured by GPC was 3,500. The epoxy equivalent was 295 g / mol.

(However, in the first unit, there are those in which x is 0, 1 or 2.)

<Examples 1 to 6, Comparative Example 1, Reference Examples 1 and 2>
Each composition shown in Table 1 was prepared using each obtained resin. In the same table, the unit of numerical values other than the curing agent is parts by mass, and each component is as follows.
-(C) Curing agent: 4-methylhexahydrophthalic anhydride (Ricacid MH, manufactured by Shin Nippon Rika Co., Ltd.)
(D) Curing catalyst: quaternary phosphonium salt (UCAT5003, manufactured by San Apro Co., Ltd.)
Silane coupling agent: 3-mercaptopropylmethyldimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-802)
Epoxy resin: 3,4-epoxycyclohexylmethyl 3 ′, 4′-epoxycyclohexanecarboxylate (Celoxide 2021P, manufactured by Daicel Chemical Industries, Ltd.)

<Example 1>
80 parts by mass of resin 1, 20 parts by mass of resin 4, a curing agent in an amount of 1 mol of acid anhydride group with respect to a total of 1 mol of epoxy groups of resin 1 and resin 4, and further, resin 1 Then, with respect to 100 parts by mass of the mixture of the resin 4 and the curing agent, 0.39 parts by mass of the curing catalyst and 0.25 parts by mass of the silane coupling agent were melt-mixed to obtain a composition. In the melt mixing, the curing agent and the curing catalyst are first melted in an oven at 60 ° C., and mixed with other ingredients at 2000 rpm for 1 minute using a stirrer (“Awatori Rentaro” (trade name), Shinky). Then, deaeration was performed at 2200 rpm for 1 minute.

<Example 2>
80 parts by mass of resin 1, 20 parts by mass of resin 5, a curing agent in an amount such that the acid anhydride group is 1 mol with respect to 1 mol in total of the epoxy groups of the resin 1 and resin 5, and the resin 1 Then, with respect to 100 parts by mass of the resin 5 and the curing agent mixture, 0.39 parts by mass of the curing catalyst and 0.25 parts by mass of the silane coupling agent were melt-mixed in the same manner as in Example 1 to obtain a composition. .

<Example 3>
80 parts by mass of resin 2, 20 parts by mass of resin 4, a curing agent in an amount of 1 mol of acid anhydride group with respect to 1 mol of the total of epoxy groups of resin 2 and resin 4, and further, resin 2 Then, with respect to 100 parts by mass of the resin 4 and the curing agent mixture, 0.39 parts by mass of the curing catalyst and 0.25 parts by mass of the silane coupling agent were melt-mixed in the same manner as in Example 1 to obtain a composition. .

<Example 4>
80 parts by mass of resin 2, 20 parts by mass of resin 5, a curing agent in an amount of 1 mol of acid anhydride group with respect to 1 mol of the total of epoxy groups of resin 2 and resin 5, and further, resin 2 Then, with respect to 100 parts by mass of the resin 5 and the curing agent mixture, 0.39 parts by mass of the curing catalyst and 0.25 parts by mass of the silane coupling agent were melt-mixed in the same manner as in Example 1 to obtain a composition. .

<Example 5>
80 parts by mass of resin 3, 20 parts by mass of resin 6, a curing agent in an amount of 1 mol of acid anhydride group with respect to a total of 1 mol of epoxy groups of resin 3 and resin 6, and further, resin 3 Then, with respect to 100 parts by mass of the mixture of the resin 6 and the curing agent, 0.39 parts by mass of the curing catalyst and 0.25 parts by mass of the silane coupling agent were melt-mixed in the same manner as in Example 1 to obtain a composition. .

<Example 6>
80 parts by mass of resin 1, 20 parts by mass of resin 4, a curing agent in an amount of 1 mol of acid anhydride group with respect to a total of 1 mol of epoxy groups of resin 1 and resin 4, and further, resin 1 Then, 0.39 parts by mass of the curing catalyst was melt-mixed in the same manner as in Example 1 with respect to 100 parts by mass of the mixture of the resin 4 and the curing agent to obtain a composition.

<Comparative Example 1>
100 parts by mass of resin 1, a curing agent in an amount of 1 mole of acid anhydride group with respect to 1 mol of epoxy group of resin 1, and further curing with respect to 100 parts by mass of mixture of resin 1 and the curing agent 0.39 parts by mass of the catalyst and 0.25 parts by mass of the silane coupling agent were melted and mixed in the same manner as in Example 1 to obtain a composition.

<Reference Example 1>
78 parts by mass of resin 1, 22 parts by mass of epoxy resin, a curing agent in an amount of 1 mol of acid anhydride group with respect to a total of 1 mol of epoxy group of resin 1 and epoxy resin, and resin 1 Then, with respect to 100 parts by mass of the mixture of the epoxy resin and the curing agent, 0.39 parts by mass of the curing catalyst and 0.25 parts by mass of the silane coupling agent were melt-mixed in the same manner as in Example 1 to obtain a composition. .

<Reference Example 2>
90 parts by mass of resin 2, 10 parts by mass of epoxy resin, a curing agent in an amount of 1 mol of acid anhydride group with respect to 1 mol of the total of epoxy groups of resin 2 and epoxy resin, and resin 2 Then, with respect to 100 parts of the mixture of the epoxy resin and the curing agent, 0.39 parts by mass of the curing catalyst and 0.25 parts by mass of the silane coupling agent were melt-mixed in the same manner as in Example 1 to obtain a composition.

(Note to Table 1) (C) The unit of components other than the curing agent is parts by mass.

<Evaluation test 1>
The following tests were conducted for each composition, and the results are shown in Table 2.
(1) Physical properties: The composition was cured by heating at 100 ° C. for 2 hours, and post-curing was performed at 150 ° C. for 4 hours to obtain a rod-shaped cured product having a thickness of 5 mm. Using this rod-like cured product, the appearance, hardness (Shore D), flexural modulus and flexural strength (JIS K-6911) were measured.
(2) Heat discoloration: The appearance after subjecting the bar-like cured product produced in the same manner as (1) to high temperature aging (150 ° C., 1000 hours) was examined.
(3) UV resistance test: The composition was molded into a cured piece (6 cm × 6 cm) having a thickness of 2 mm by press molding at 100 ° C. for 30 minutes, and then post-cured at 150 ° C. for 4 hours to prepare a test piece. The light transmittance after UV irradiation (high pressure mercury lamp 30 mW / cm ² , 365 nm) was measured on the test piece for 2 hours. The transmittance was measured by scanning from 800 to 300 nm, and the transmittance when the initial transmittance at 400 nm was taken as 100% was determined.
(4) A tape made of polytetrafluoroethylene (thickness 180 μm) is pasted on the slide glass along the outer periphery of the slide glass, and the composition is poured into the formed recess, and further at 100 ° C. for 2 hours. Post-curing was performed at 150 ° C. for 4 hours to form a thin film cured product. The microhardness of the thin film cured product was measured using an ultra micro hardness meter (Shimadzu Corporation, DUH-W201S).

(Note to Table 2)
* 1: The cured product was brittle and the bending strength could not be measured.
* 2: The cured product was rubber-like and the bending strength could not be measured.

<Evaluation Test 2>
The following tests were conducted for each composition, and the results are shown in Table 3.

-Production and evaluation of LED device Using the compositions of Examples 1 and 3 and Comparative Example 1, three LED devices were produced by the following method. An InGaN-based blue light-emitting element was fixed with a silver paste on a pre-molded package for LED having a thickness of 1 mm, a side of 3 mm, an opening of 2.6 mm in diameter, and a bottom of which was silver-plated. Next, the external electrode and the light emitting element were connected by a gold wire. Each composition was injected into the package opening. The composition was cured at 100 ° C. for 1 hour and further at 150 ° C. for 2 hours to produce an LED device. Using the created LED device, a temperature cycle test under the following conditions and an LED lighting test (LED wavelength: 450 nm) at 65 ° C./95% RH were conducted for 500 hours, and adhesion failure at the package interface, presence or absence of cracks, and The presence or absence of discoloration was visually observed. The results are shown in Table 3.

..Temperature cycle test conditions:
One cycle: 20 minutes at -40 ° C, then 20 minutes at 125 ° C.

    Repeat cycle number: 1000

・ Adhesive strength:
Using the compositions of Examples 1 and 3 and Comparative Example 1, adhesion test pieces were prepared by the following method. Each composition was thinly applied on a silver-plated copper plate, and a 2 mm square silicon chip was placed and cured at 100 ° C. for 1 hour and further at 150 ° C. for 2 hours to prepare an adhesion test piece. For the created adhesion test piece, the adhesion force at the time of cutting is measured using a die bond tester (device name: Dage Series 4000 Bondtester, test speed: 200 μm / s, test height: 10.0 μm, measurement temperature: 25 ° C.). did.

As can be seen from the results shown in Tables 2 and 3, the cured product obtained from the composition of Comparative Example 1 lacking the component (B) was poor in bending strength and heat discoloration, and was discolored by the light of the LED. Moreover, it replaced with (B) component and the hardened | cured material obtained from the composition of the reference example containing an epoxy resin yellowed with the heat | fever. On the other hand, the cured products obtained from the compositions of the examples had high hardness and almost no discoloration. Moreover, as can be seen from the microhardness values in Table 2, the compositions of the examples give a cured product having a higher hardness than the compositions of the comparative example and the reference example cured under the same conditions, and the curing rate is high. Was confirmed.

The composition of the present invention is rapidly cured, and the cured product is excellent in heat discoloration resistance, UV resistance and the like, and is useful for optical element sealing resins.

Claims (9)

Following (A), (B), see containing the (C) and component (D), (A) an epoxy equivalent weight of component 200 to 800 g / mol, (B) an epoxy equivalent of component (A) component of Composition for optical semiconductor element encapsulation at least 30 g / mol smaller than epoxy equivalent (A) First silicone resin having an epoxy group-containing non-aromatic group represented by the following average composition formula (1) Parts by mass

(In the formula (1), R ¹ is an epoxy group-containing non-aromatic group, R ² is independently a group selected from a hydroxyl group, a C _1-20 monovalent hydrocarbon group, and a C _1-6 alkoxy group, R ³ _Are independently of each other a C _1-20 monovalent hydrocarbon group,
x and y are each independently an integer of 0, 1 or 2;
a is a number from 0.25 to 0.75,
b is a number from 0.25 to 0.75,
c is a number from 0 to 0.3, where a + b + c = 1,
n is an integer of 2 to 20)
(B) 10-50 mass parts of 2nd silicone resins which have an epoxy-group-containing non-aromatic group represented by the following average compositional formula (2)

(In the formula (2), R ¹ , R ² and R ³ are as described above, z is an integer of 0, 1 or 2 independently of each other;
d is a number from 0.5 to 0.8,
e is a number from 0.2 to 0.5,
(D + e = 1)
(C) Curing agent having functional group reactive with epoxy group (A) The functional group reactive with the epoxy group is 0.4 mol in total for 1 mol of the epoxy group in the component (A) and the component (B). The amount which becomes -1.5 mol (D) Curing catalyst 0.01-3 weight part with respect to a total of 100 mass parts of (A) component and (B) component.   The composition according to claim 1, wherein n is an integer of 3 to 20.   The composition according to claim 1, wherein the component (A) has a polystyrene-equivalent weight average molecular weight of 3,000 to 10,000. The composition according to claim 1, wherein R ¹ is a β- (3,4-epoxycyclohexyl) ethyl group or a γ-glycidoxyalkyl group. The composition according to claim 1, wherein R ³ is a methyl group.   The composition according to claim 1, wherein the epoxy equivalent of component (A) is 300 to 600 g / mol, and the epoxy equivalent of component (B) is 250 to 400 g / mol.   The composition according to claim 1, wherein the component (C) is an acid anhydride.   The composition according to claim 1, further comprising a mercapto-based silane coupling agent. The semiconductor device which has an optical semiconductor element and the hardened | cured material which hardens the composition of any one of Claims 1-8 , and seals this optical semiconductor element.

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