TWI480338B - Resin composition for encapsulating optical semiconductor element - Google Patents

Description

Resin composition for encapsulating an optical semiconductor element

The present invention relates to a composition for encapsulating an optical semiconductor element, and more particularly to a composition for encapsulating an optical semiconductor element, wherein the matrix resin is substantially composed of a polyoxyxene resin and exhibits Excellent heat discoloration and superior curability.

Epoxy resin compositions are well known for use in encapsulating optical semiconductor components. These epoxy resin compositions typically comprise an alicyclic epoxy resin acting as a matrix resin, a curing agent, and a curing catalyst. The optical semiconductor element is encapsulated by a casting or transfer molding method or the like, typically by pouring a resin composition into a mold in which an optical semiconductor element has been placed, and then curing the resin composition. However, as the brightness and power output of LEDs increase, problems with discoloration and degradation of epoxy resins have begun to appear. In particular, alicyclic epoxy resins tend to yellow when exposed to blue light or ultraviolet light, resulting in a shortened life of the LED elements.

Therefore, polyoxyxene resins exhibiting excellent heat resistance and light resistance are currently used, but the strength of the cured resin is weaker than that of the epoxy resin. In order to overcome this problem, it has been proposed to use a high-hardness rubber-like polyphthalocyanine resin for capsule encapsulation applications (for example, see Patent Document 1). However, such high-hardness polyoxyxene resins exhibit weak adhesion and are embedded in the light-emitting semiconductor device (ie, the light-emitting element is placed inside the ceramic and/or plastic casing, and then the inside of the casing is filled with polyoxynated resin). In the device, the thermal shock test at -40 ° C to 120 ° C tends to separate the polyoxyn resin from the ceramic or plastic of the outer casing.

In order to improve adhesion and thermal shock resistance, a polyoxyalkylene resin containing an epoxy group has been proposed (see Patent Document 2). However, these polyoxyxylene resins are synthesized by condensing an epoxy group-containing decane with a decyl alcohol, and the cured products of these polyoxyxylene resins are easily broken and have a low modulus of elasticity. Therefore, LEDs encapsulated with this type of resin capsule are prone to cracks in the resin during temperature cycle testing.

Known materials for solving this cracking problem include a composition comprising an epoxy resin and sesquioxane containing at least two epoxy rings (see Patent Document 3), and an epoxy resin as a stress reducing agent and containing A composition of a polyanthracene resin of an isocyanuric acid-derived group (see Patent Document 4). However, even with these two types of compositions, cracking was observed during the temperature cycle test of the cured product, and it was asserted that neither of the two types of compositions could provide a completely satisfactory thermal shock resistance.

[Previous Technical Literature]

[Patent Document 1] JP 2002-314143 A

[Patent Document 2] JP 7-97433 A

[Patent Document 3] JP 2005-263869 A

[Patent Document 4] JP 2004-99751 A

An object of the present invention is to solve the problems outlined above, and to provide a resin composition for encapsulating an optical semiconductor element, which is capable of forming not only high hardness, excellent light resistance, and excellent thermal shock resistance, but also has A significantly improved heat-resistant, color-changing capsule encapsulates the cured product with good cure rates and similar properties.

As a result of various studies, the inventors of the present invention have found that an epoxy-modified polyoxynoxy resin having a specific linear polyoxyalkylene structure as described above and an epoxy obtained by condensing two organic decanes are obtained. The above object can be attained by a combination of a base-equivalent amount of a second epoxy-modified polyoxyl resin which is lower than the above epoxy-modified polyoxyl resin, and the inventors are thus able to complete the present invention.

In other words, the present invention provides a composition for encapsulating an optical semiconductor element comprising the components (A), (B), (C) and (D) described below:

(A) a first polyoxynoxy resin having an epoxy group-containing non-aromatic group represented by an average composition formula (1) shown below, and an amount of 50 parts by mass to 90 parts by mass,

Wherein R ¹ represents a non-aromatic group containing an epoxy group, and each R ² independently represents a member selected from the group consisting of a hydroxyl group, a C ₁ to C ₂₀ monovalent hydrocarbon group, and a C ₁ to C ₆ alkoxy group, each R ³ represents C ₁ to C ₂₀ monovalent hydrocarbon group, x and y each independently represent an integer of 0, 1 or 2, a represents a value in the range of 0.25 to 0.75, b represents a value in the range of 0.25 to 0.75, and c represents a value of 0 to A value in the range of 0.3, the constraint is a + b + c = 1, and n represents an integer from 2 to 20,

(B) a second polyoxyalkylene resin having an epoxy group-containing non-aromatic group represented by an average composition formula (2) shown below in an amount of 10 parts by mass to 50 parts by mass,

Wherein R ¹ , R ² and R ³ are as defined above, each z independently represents an integer of 0, 1 or 2, d represents a value in the range from 0.5 to 0.8, and e represents a value in the range from 0.2 to 0.5, The constraint is d+e=1,

(C) a curing agent having a functional group reactive with an epoxy group in an amount of from 0.4 mol to 1.5 mol per 1 mol of all epoxy groups in the component (A) and the component (B) a functional group capable of reacting with an epoxy group, and

(D) A curing catalyst in an amount of from 0.01 part by mass to 3 parts by mass per 100 parts by mass of the combination of the component (A) and the component (B).

Since the resin composition of the present invention contains the above second polyfluorene oxide resin, a cured product having high hardness can be formed. Further, since the second polyoxyl resin exhibits a high degree of reactivity, an optical semiconductor package having excellent heat discoloration resistance can be manufactured in a relatively short period of time.

<component (A)>

In the composition of the present invention, the first polyfluorene oxide resin (A) having an epoxy group-containing non-aromatic group is represented by the average composition formula (1) shown below.

In the formula (1), n represents an integer of 2 to 20, preferably an integer of 3 to 20, and more preferably an integer of 3 to 10. x and y each independently represent an integer of 0, 1, or 2. As the first structural unit of the first polyoxyl resin to which the subscript "a" is attached and the third structural unit to which the subscript "c" is attached, x or y is a 0 oxane unit ( The T unit), the x-oxane unit (D unit) in which x or y is 1, and the oxane unit (M unit) in which x or y is 2 usually coexist in the resin molecule. The ratio of such oxoxane units in each of the first and third structural units depends on the type of R ² in the monomers used in the manufacturing process described below and the degree of hydrolysis and condensation of the monomers. T unit: D unit: The M unit of the M unit is preferably in the range of 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 more preferably 80:10:10 to 95:3:2.

When, for example, n is 3, the unit represented by (R ³ ₂ SiO) _n in the formula (1) has the structure shown below.

When the polyoxyxene resin has a linear structure, the (R ³ ₂ SiO) _n unit may be present in the main chain, or when the polyfluorene oxide resin has a branched structure, the (R ³ ₂ SiO) _n unit may be bonded to Branch chain. The inclusion of this (R ³ ₂ iO) _n unit makes it possible to obtain a cured product having excellent thermal shock resistance.

In the formula (1), R ¹ represents an epoxy group-containing non-aromatic group, and examples thereof include a linear or branched aliphatic group containing an epoxy group such as a γ-glycidoxyalkyl group (for example, γ- Glycidoxyethyl); an epoxy group-containing alicyclic group such as β-(3,4-epoxycyclohexyl)ethyl; and an epoxy group-containing heterocyclic group such as monoglycidyl group Isocyanuramide or diglycidyl isocyanurate. Among such groups, an epoxy group-containing alicyclic group is preferred, and a β-(3,4-epoxycyclohexyl)ethyl group is particularly desirable. Meanwhile, it is assumed that a non-aromatic group containing an oxetane group instead of an epoxy group is also used; however, the epoxy group is more excellent in terms of curability. Further, at least one R ¹ group is preferably present per molecule, and more preferably 2 to 100 R ¹ per molecule. The R ¹ group is preferably present at the end of the molecule. For example, when the molecule has a linear structure, it is preferred to have one R ¹ at each end of the molecule.

R ² represents a member selected from the group consisting of a hydroxyl group, a C ₁ to C ₂₀ monovalent hydrocarbon group, and a C ₁ to C ₆ alkoxy group. Examples of monovalent hydrocarbon groups include alkyl groups such as methyl, ethyl, propyl or butyl; cycloalkyl groups such as cyclopentyl or cyclohexyl; aryl groups such as phenyl; alkylaryl groups such as tolyl; A bicyclic group, such as a norbornene group. Examples of the C ₁ to C ₆ alkoxy group include a methoxy group and an ethoxy group. R ^{2 is} preferably a methyl group or a phenyl group.

Each R ³ represents a C ₁ to C ₂₀ monovalent hydrocarbon group. Specific examples include the same groups as listed in the above R ² description.

a represents a value in the range of 0.25 to 0.75, and preferably a value of 0.4 to 0.7. If the value of a is less than the lower limit of the range, since the amount of the epoxy group is small, the curing rate of the composition tends to decrease. On the contrary, if the value of a exceeds the upper limit of the above range, since the amount of the epoxy group is extremely large, the synthesized resin is easily gelled, which is undesirable. b represents a value in the range of 0.25 to 0.75, and preferably a value of 0.3 to 0.6. c represents a value in the range of 0 to 0.3, and preferably a value of 0 to 0.2. If the value of c exceeds the upper limit of this range, the light resistance of the cured product tends to deteriorate. Formula (1) is a composition formula indicating the average existence ratio of each structural unit, where a+b+c=1.

The component (A) can be obtained by subjecting the following materials to hydrolysis and condensation reaction according to a conventional method: a linear organopolyoxane represented by the formula (3) shown below:

(wherein R ^{3 is} as defined above, X represents a hydrolyzable group such as an alkoxy group or a halogen atom, and m is an integer of 0 to 18), and an epoxy group-containing decane represented by the formula shown below:

(wherein R ¹ and R ² are as defined above, the restriction is that at least one R ² is a hydroxyl group or a C ₁ to C ₆ alkoxy group), and optionally a decane represented by the formula (5):

(wherein R ² and R ³ are as defined above, with the proviso that at least one R ² is hydroxy or C ₁ to C ₆ alkoxy).

The polystyrene equivalent average molecular weight of the component (A) is typically in the range of 3,000 to 10,000, and preferably 3,000 to 6,000. Further, the epoxy equivalent is typically in the range of from 200 g/mol to 800 g/mol, and preferably from 300 g/mol to 600 g/mol.

<component (B)>

The second polyfluorene oxide resin (B) having a non-aromatic group containing an epoxy group is represented by the average composition formula (2) shown below.

In the formula (2), R ¹ , R ² and R ³ are as defined above. Each z independently represents an integer of 0, 1, or 2. As the first structural unit constituting the second polyoxyl resin with the subscript "d", x is a oxoxane unit (T unit), x is a decane unit (D unit), and x is The 2 oxane unit (M unit) usually coexists in its molecule. The ratio of such oxane units depends on the kind of R ² in the monomer used in the production method described below and the degree of hydrolysis and condensation of the monomer. T unit: D unit: M unit of the molar is preferably in the range of 10:30:60 to 98:1:1, more preferably 40:30:30 to 98:1:1, more preferably 60:20 : 20 to 96: 2: 2, and more preferably in the range of 80: 10: 10 to 95: 3: 2.

d represents a value in the range of 0.5 to 0.8, and preferably a value of 0.5 to 0.7. If the value of d is less than the lower limit of the range, the composition becomes difficult to cure, and if the value of d exceeds the upper limit, the resin becomes difficult to synthesize and the composition tends to be gelled. e represents a value in the range of 0.2 to 0.5, and preferably a value of 0.3 to 0.5, and the constraint is d + e = 1.

The method of producing the component (B) is different from the method of producing the component (A) in that, during the preparation of the resin, the organic decane represented by R ³ ₂ X ₂ Si is used instead of the component (A) Linear organopolyoxane of the formula (3). In the condensation reaction, the organodecane and the epoxy group-containing decane represented by the formula (4) are subjected to hydrolysis and condensation reaction to produce a second polyoxyl resin of the component (B). Therefore, the component (B) is substantially free of the (R ³ ₂ SiO) _n unit contained in the component (A), and it is considered that the component (B) has a function similar to the crosslinking point in the cured product, thereby Increase the strength of the cured product. Therefore, the composition of the present invention can form a cured product having excellent hardness and thermal shock resistance and the like, even if it does not use a combination of an epoxy resin and a polyoxyxylene resin, and in particular, is not widely used for capsules. An alicyclic epoxy resin encapsulating an optical semiconductor element. Since the cured product does not contain the epoxy resin, it does not undergo thermal discoloration.

The polystyrene equivalent average molecular weight of the component (B) is typically in the range of 3,000 to 10,000, and preferably 3,000 to 7,000. The epoxy equivalent of the component (B) is typically in the range of from 100 g/mol to 600 g/mol, and preferably from 250 g/mol to 400 g/mol. It is especially desirable that the epoxy equivalent of component (B) is less than about 30 g/mol to 300 g/mol of the epoxy group equivalent of component (A).

The blending amount of the component (B) is typically in the range of 10 parts by mass to 50 parts by mass, preferably 10 parts by mass to 30 parts by mass per 100 parts by mass of the combination of the component (A) and the component (B). If the amount of the component (B) exceeds the upper limit of the range, the cured product of the resin composition is liable to be degraded by ultraviolet light in the case where the light-emitting element emits ultraviolet light. Further, when subjected to heating for a long period of time, the cured product also tends to crack.

<component (C)>

Examples of the curing agent (C) include an amine-based curing agent, a phenol-based curing agent, and an acid anhydride-based curing agent, and among these curing agents, an acid anhydride-based curing agent is preferred.

Examples of the acid anhydride-based curing agent include phthalic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, 3-methyl-hexahydrophthalic anhydride, 4- Mixture of methyl-hexahydrophthalic anhydride, 3-methyl-hexahydrophthalic anhydride and 4-methyl-hexahydrophthalic anhydride Compound, tetrahydrophthalic anhydride, nadic anhydride, methyl acid anhydride, norbornane-2,3-dicarboxylic anhydride and methylnorbornane-2,3-dicarboxylic anhydride . The curing agent (C) is blended in an amount of from 0.4 moles to 1.5 moles and preferably from 0.5 moles to 1.2 per 1 mole of all epoxy groups in the combination of component (A) and component (B). Mohr exhibits a functional group reactive with an epoxy group (in the case of an acid anhydride curing agent, an acid hydride group having -CO-O-CO-).

<component (D)>

Examples of the curing catalyst (D) include a curing catalyst based on a quaternary phosphonium salt such as tetrabutylphosphonium O, O-diethyldithiophosphate and tetraphenylphosphonium tetraphenylborate; a curing catalyst based on an organic phosphine, Such as triphenylphosphine and diphenylphosphine; a curing catalyst based on a tertiary amine such as 1,8-diazabicyclo(5,4,0)undec-7-ene, triethanolamine and benzyl di Methylamine; a curing catalyst based on a quaternary ammonium salt such as 1,8-diazabicyclo(5,4,0)undec-7-enphenolate, 1,8-diazabicyclo (5,4 , 0) undec-7-ene octanoate and 1,8-diazabicyclo(5,4,0)undec-7-ene tosylate; and an imidazole-based curing catalyst such as 2- Methylimidazole and 2-phenyl-4-methylimidazole. Among these curing catalysts, a quaternary phosphonium salt and a quaternary ammonium salt are preferred.

The blending amount of the curing catalyst (D) is typically in the range of 0.01 part by mass to 3 parts by mass and preferably 0.05 part by mass to 0.5 part by mass per 100 parts by mass of the combination of the component (A) and the component (B). If the blending amount of the curing catalyst is less than the lower limit of the range, the catalyst may not provide sufficient acceleration of the reaction between the epoxy resin and the curing agent. On the contrary, if the blending amount of the curing catalyst exceeds the upper limit of the above range, the curing catalyst may cause discoloration during curing or during the reflow test.

In addition to the above components, such as antioxidants, UV absorbers, anti-aging agents, phosphors for changing wavelengths, inorganic fillers (such as cerium oxide or titanium oxide fine powder), decane coupling agents, thermoplastics and dilution The additive of the agent may also be included in the composition of the present invention as needed, without being impaired for the purpose of the present invention. Antioxidants based on hindered phenols and phosphorus-based antioxidants are preferred as antioxidants. A UV absorber based on a hindered amine is preferred as the ultraviolet absorber. A mercapto-based decane coupling agent is preferred as the decane coupling agent.

The compositions of the present invention can be relatively easily combined by combining components (A) through (D) with one or more optional additives optionally selected, and then at a temperature of about 60 ° C (which is sufficiently low to prevent curing). Manufactured by performing melt mixing. Melt mixing can be carried out using a conventional method. For example, the above components may be combined in a reactor, wherein melt mixing is then carried out in a batch process, or each of the above components may be supplied to a mixing device such as a kneader or a three-roll mill, in a continuous manner Melt mixing is carried out.

The resin composition thus obtained for encapsulating an optical semiconductor element can be injected into a mold or an outer casing of an internally mounted light-emitting element by a resin composition in the form of a molten mixture obtained by the above method, followed by a resin at a predetermined temperature The composition was subjected to B-staging, and then the composition was solidified and used.

Further, the resin composition can also be used to protect an LED mounted on a substrate by applying the composition to the LED by using a potting method, a printing method, a transfer molding method, an injection molding method, or a compression molding method. In the case where a light-emitting semiconductor device such as an LED is coated and protected by potting or injection molding, the composition of the present invention is preferably in a liquid form. In other words, the viscosity of the resin composition (reported as a value measured by rotational viscosity at 25 ° C) is preferably in the range of 10 mPa ‧ s to 1,000,000 mPa ‧ and more preferably 100 mPa ‧ to 1,000,000 mPa ‧ s . On the other hand, in the case where the light-emitting semiconductor device is manufactured by transfer molding or the like, a liquid resin of the above type may be used, or the production may be solidified by a viscosity increase (B-stage treatment) and then The solid is granulated and subsequently molded.

Example

The invention is described in more detail below based on a series of examples and comparative examples, but the invention is in no way limited by the examples presented below.

[synthetic component (A)]

In the synthesis example, the average of n in the average composition of the product is the product of the peak area of the other n (i.e., the multiplicative product) in the graph representing the molecular weight distribution measured by GPC. The sum is divided by the total area of all peaks. For example, in the case where n ranges from 2 to 20 in the product, the average value of n is calculated by the following equation: [2 × (n is the peak area of 2) + 3 × (n is the peak area of 3) +...+20×(n is the peak area of 20)]/[(n is the peak area of 2)+(n is the peak area of 3)+...+ (n is the peak area of 20)].

<Synthesis Example 1>

The reaction flask was charged with 1,695.6 g (5.966 mol) MeO(Me) ₂ SiO(Me ₂ SiO) _m Si(Me) ₂ OMe (wherein m is an integer from 0 to 8, and the average value of m is 1.5) 3,000 ml of isopropanol and 1,470 g (5.966 mol) of 3-(3,4-epoxycyclohexyl)ethyltrimethoxydecane (KBM303, manufactured by Shin-Etsu Chemical Co., Ltd.), followed by 72 g A 25% aqueous solution of tetramethylammonium hydroxide and 648 g of water were added, and the resulting mixture was stirred at room temperature for 3 hours. After the reaction was completed, 3,000 ml of toluene was added to the reaction system. The reaction mixture was then neutralized with an aqueous solution of sodium dihydrogen phosphate, and the separated organic layer was washed with hot water using a separating funnel. Next, toluene was removed under reduced pressure to give a target resin ("resin 1") having a structure represented by the following average composition formula.

- The polystyrene equivalent average molecular weight measured by GPC was 4,300. The epoxy equivalent weight was 403 g/mol.

- The results obtained by measurement using ²⁹ Si-NMR are shown in Fig. 1. The peak appearing around -68 ppm reflects the ruthenium atom forming the T unit, and the peak appearing at about -57 ppm to about -58 ppm reflects the ruthenium atom forming a combination of the D unit and the M unit. Thus, it is shown that the first structural unit (left unit) in the following average composition formula contains about 90 mole % T unit and about 10 mole % combination of D unit and M unit.

Wherein each n is an integer from 2 to 10, and an average value of n is 3.5, and units in which x is 0, 1, or 2 coexist in the first unit.

<Synthesis Example 2>

The reaction flask was charged with 1,500 g (1.975 mol) of HO(Me) ₂ SiO(Me ₂ SiO) _m Si(Me) ₂ OH (wherein m is an integer from 3 to 18, and the average value of m is 8) , 973.2 g (3.950 mol) of 3-(3,4-epoxycyclohexyl)ethyltrimethoxydecane (KBM303, manufactured by Shin-Etsu Chemical Co., Ltd.) and 2,300 ml of isopropanol, followed by addition of 49.90 g 25% aqueous solution of tetramethylammonium hydroxide and 449.10 g of water, and the resulting mixture was stirred at room temperature for 3 hours. After the reaction was completed, 2,300 ml of toluene was added to the reaction system, and the reaction mixture was neutralized with an aqueous solution of sodium dihydrogen phosphate. The separated organic layer was then washed with hot water using a separatory funnel. Toluene was removed under reduced pressure to give a target resin ("resin 2") having a structure represented by the following average composition formula. The polystyrene equivalent average molecular weight measured by GPC was 5,600. The epoxy equivalent weight was 570 g/mol.

Wherein each n is an integer from 5 to 20, and an average value of n is 10, and a unit in which x is 0, 1, or 2 coexists in the first unit.

<Synthesis Example 3>

The reaction flask was charged with 933.30 g (3.950 mol) of 3-glycidoxypropyltrimethoxydecane (KBM403, manufactured by Shin-Etsu Chemical Co., Ltd.), 1,500 g (1.975 mol) of HO(Me) ₂ SiO[(Me) ₂ SiO] _m Si(Me) ₂ OH (wherein m is an integer from 3 to 18, and the average of m is 8) and 2,300 ml of isopropanol, followed by addition of 92.15 g of 25% hydrido Aqueous methylammonium solution and 444.96 g of water were added, and the resulting mixture was stirred at room temperature for 3 hours. After the reaction was completed, 2,300 ml of toluene was added to the reaction system, and the reaction mixture was neutralized with an aqueous solution of sodium dihydrogen phosphate. The separated organic layer was then washed with hot water using a separatory funnel. Toluene was removed under reduced pressure to give a target resin ("resin 3") having a structure represented by the following average composition formula. The polystyrene equivalent average molecular weight measured by GPC was 4,300. The epoxy equivalent weight was 570 g/mol.

Wherein each n is an integer from 5 to 20, and an average value of n is 10, and a unit in which x is 0, 1, or 2 coexists in the first unit.

[synthetic component (B)]

<Synthesis Example 4>

The reaction flask was charged with 187.00 g (1.566 mol) of dimethyldimethoxydecane (KBM-22, manufactured by Shin-Etsu Chemical Co., Ltd.), 766.67 g (3.111 mol) 3-(3,4- Epoxycyclohexyl)ethyltrimethoxydecane (KBM303, manufactured by Shin-Etsu Chemical Co., Ltd.) and 900 ml of isopropanol, followed by addition of 21.69 g of 25% aqueous solution of tetramethylammonium hydroxide and 195.21 g of water, and The resulting mixture was stirred at room temperature for 3 hours. After the reaction was completed, 1,000 ml of toluene was added to the reaction system, and the reaction mixture was neutralized with an aqueous solution of sodium dihydrogen phosphate. The separated organic layer was then washed with hot water using a separatory funnel. Toluene was removed under reduced pressure to give a target resin ("resin 4") having a structure represented by the following average composition formula. The polystyrene equivalent average molecular weight measured by GPC was 4,200. The epoxy equivalent weight was 267 g/mol.

Units in which x is 0, 1, or 2 coexist in the first unit.

<Synthesis Example 5>

The reaction flask was charged with 187.00 g (1.566 mol) of dimethyldimethoxydecane (KBM-22, manufactured by Shin-Etsu Chemical Co., Ltd.), 383.33 g (1.566 mol) 3-(3,4- Epoxycyclohexyl)ethyltrimethoxydecane (KBM303, manufactured by Shin-Etsu Chemical Co., Ltd.) and 540 ml of isopropanol, followed by 12.97 g of 25% aqueous solution of tetramethylammonium hydroxide and 203.93 g of water, and The resulting mixture was stirred at room temperature for 3 hours. After the reaction was completed, 1,000 ml of toluene was added to the reaction system, and the reaction mixture was neutralized with an aqueous solution of sodium dihydrogen phosphate. The separated organic layer was then washed with hot water using a separatory funnel. Toluene was removed under reduced pressure to give a target resin ("resin 5") having a structure represented by the following average composition formula. The polystyrene equivalent average molecular weight measured by GPC was 3,100. The epoxy equivalent weight was 359 g/mol.

Units in which x is 0, 1, or 2 coexist in the first unit.

<Synthesis Example 6>

The reaction flask was charged with 187.00 g (1.566 mol) of dimethyldimethoxydecane (KBM-22, manufactured by Shin-Etsu Chemical Co., Ltd.), 735.24 g (3.111 mol) 3-glycidoxypropyl Trimethoxy decane (KBM403, manufactured by Shin-Etsu Chemical Co., Ltd.) and 900 ml of isopropanol, followed by addition of 20.98 g of 25% aqueous solution of tetramethylammonium hydroxide and 188.82 g of water, and the resulting mixture was stirred at room temperature. 3 hours. After the reaction was completed, 1,000 ml of toluene was added to the reaction system, and the reaction mixture was neutralized with an aqueous solution of sodium dihydrogen phosphate. The separated organic layer was then washed with hot water using a separatory funnel. Toluene was removed under reduced pressure to give a target resin ("resin 6") having a structure represented by the following average composition formula. The polystyrene equivalent average molecular weight measured by GPC was 3,500. The epoxy equivalent weight was 295 g/mol.

Units in which x is 0, 1, or 2 coexist in the first unit.

<Examples 1 to 6, Comparative Example 1, Reference Examples 1 and 2>

Using the resin obtained above, the composition was prepared using the formulation shown in Table 1. In Table 1, the numerical values listed for each component (excluding the curing agent) indicate "parts by mass". The other components used in the composition are listed below.

(C) Curing agent: 4-methylhexahydrophthalic anhydride (RIKACID MH, manufactured by New Japan Chemical Co., Ltd.)

(D) Curing catalyst: quaternary phosphonium salt (UCAT5003, manufactured by San-Apro Co., Ltd.)

Decane coupling agent: 3-mercaptopropylmethyldimethoxydecane (KBM-802, manufactured by Shin-Etsu Chemical Co., Ltd.)

Epoxy resin: 3,4-epoxycyclohexane methyl 3',4'-epoxycyclohexanecarboxylate (CELLOXIDE 2021P, manufactured by Daicel Chemical Industries Co., Ltd.)

<Example 1>

80 parts by mass of the resin 1, 20 parts by mass of the resin 4, a curing agent in an amount of 1 mole of the anhydride group per 1 part of the epoxy resin 1 and 4, and 1 to 4 parts per 100 parts by mass of the resin 1 and 4 0.39 parts by mass of a curing catalyst and 0.25 parts by mass of a decane coupling agent were melt-mixed with a mixture of curing agents to obtain a composition. Melt mixing was carried out by first melting the curing agent and curing the catalyst in an oven at 60 ° C, followed by mixing with the other components at 2,000 rpm for 1 minute using a mixer (product name: Thinky Mixer, manufactured by Thinky Corporation), and then at 2,200 Perform defoaming for 1 minute at rpm to perform.

<Example 2>

80 parts by mass of the resin 1, 20 parts by mass of the resin 5, a curing agent in an amount of 1 mole of the anhydride group per 1 part of the epoxy resin 1 and 5, and 1 to 5 parts per 100 parts by mass of the resin 1 and 5 The mixture with the curing agent, 0.39 parts by mass of the curing catalyst and 0.25 parts by mass of the decane coupling agent were melt-mixed in the same manner as in Example 1 to obtain a composition.

<Example 3>

80 parts by mass of the resin 2, 20 parts by mass of the resin 4, a curing agent in an amount of 1 mole of the anhydride group per 1 part of the epoxy resin 2 and 4, and 2 parts by mass per 100 parts by mass of the resin 2 and 4 The mixture with the curing agent, 0.39 parts by mass of the curing catalyst and 0.25 parts by mass of the decane coupling agent were melt-mixed in the same manner as in Example 1 to obtain a composition.

<Example 4>

80 parts by mass of the resin 2, 20 parts by mass of the resin 5, a curing agent in an amount of 1 mole of the anhydride group per 1 part of the epoxy resin 2 and 5, and 2 parts by mass per 100 parts by mass of the resin 2 and 5 The mixture with the curing agent, 0.39 parts by mass of the curing catalyst and 0.25 parts by mass of the decane coupling agent were melt-mixed in the same manner as in Example 1 to obtain a composition.

<Example 5>

80 parts by mass of the resin 3, 20 parts by mass of the resin 6, a curing agent in an amount of 1 mole of the anhydride group per 1 part of the epoxy resin 3 and 6 and 100 parts by mass of the resin 3 and 6 The mixture with the curing agent, 0.39 parts by mass of the curing catalyst and 0.25 parts by mass of the decane coupling agent were melt-mixed in the same manner as in Example 1 to obtain a composition.

<Example 6>

80 parts by mass of the resin 1, 20 parts by mass of the resin 4, a curing agent in an amount of 1 mole of the anhydride group per 1 part of the epoxy resin 1 and 4, and 1 to 4 parts per 100 parts by mass of the resin 1 and 4 The mixture with the curing agent, 0.39 parts by mass of the curing catalyst, was melt-mixed in the same manner as in Example 1 to obtain a composition.

<Comparative Example 1>

100 parts by mass of the resin 1, a curing agent in an amount of 1 mole of anhydride group per 1 part of the epoxy resin, and 0.39 parts by mass of a curing catalyst per 100 parts by mass of the mixture of the resin 1 and the curing agent 0.25 parts by mass of a decane coupling agent was melt-mixed in the same manner as in Example 1 to obtain a composition.

<Reference Example 1>

78 parts by mass of the resin 1, 22 parts by mass of the epoxy resin, a curing agent in an amount of 1 mole of anhydride group per 1 part of the epoxy resin 1 and the epoxy group, and 100 parts by mass of the resin per 100 parts by mass of the resin 1. A mixture of an epoxy resin and a curing agent 0.39 parts by mass of a curing catalyst and 0.25 parts by mass of a decane 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 the resin 2, 10 parts by mass of the epoxy resin, a curing agent in an amount of 1 mole of anhydride group per 1 part of the epoxy resin 2 and all epoxy groups in the epoxy resin, and a resin per 100 parts by mass of the resin 2. A mixture of an epoxy resin and a curing agent 0.39 parts by mass of a curing catalyst and 0.25 parts by mass of a decane coupling agent were melt-mixed in the same manner as in Example 1 to obtain a composition.

<Evaluation Test 1>

The following tests were performed on 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 then post-cured by heating at 150 ° C for 4 hours, thereby forming a rod-shaped cured product having a thickness of 5 mm. The appearance, hardness (Shore D), flexural modulus, and flexural strength (JIS K-6911) of the rod-shaped cured product were measured.

(2) Heat discoloration property: The rod-shaped cured product prepared in the same manner as in the above (1) was subjected to high temperature aging (1,000 hours at 150 ° C), and then the appearance was also measured.

(3) UV resistance: The composition was pressure molded at 100 ° C for 30 minutes to produce a cured product having a measurement of 6 cm × 6 cm × 2 mm (thickness), and then the cured product was post-cured at 150 ° C. 4 hours to prepare a sample. The transmittance was measured after 12 hours of UV irradiation (using a high pressure mercury lamp: 30 mW/cm ² , 365 nm). Transmittance was measured by scanning at 800 nm to 300 nm, where the initial transmittance at 400 nm was considered to be 100%.

(4) For each composition, a slide glass was prepared by adhering a polytetrafluoroethylene tape (thickness: 180 μm) to the periphery of the slide glass, and then the composition was poured into the obtained concave groove, Subsequently, it was cured by heating at 100 ° C for 2 hours, and then post-cured at 150 ° C for 4 hours, thereby forming a film cured product. The microhardness of the cured product of the film was measured using an ultramicro hardness tester (DUH-W201S, manufactured by Shimadzu Corporation).

<Evaluation Test 2>

-Manufacture and evaluation of LED devices -

Using each of the compositions from Examples 1 and 3 and Comparative Example 1, three LED devices having respective compositions were prepared using the method described below. Using a pre-molded LED package with a thickness of 1 mm, a length of 3 mm on one side and a 2.6 mm diameter opening (the bottom of the opening is silver plated), a silver paste is used to fix the InGaN-based blue light emitting element to the bottom. Subsequently, an external electrode is connected to the light-emitting element using a gold wire. One of the above compositions is then injected into the package opening. The composition of the LED device was completed by heating at 100 ° C for 1 hour and then heating at 150 ° C for 2 hours to cure the composition. The prepared LED device was subjected to a temperature cycle test under the conditions listed below, and subjected to a 500-hour LED luminescence test (LED wavelength: 450 nm) at 65 ° C and 95% RH, and then visually evaluated at the package interface. Adhesion failure, the presence of cracks and the presence of discoloration. The results are shown in Table 3.

--Temperature cycle test conditions --

One cycle: 20 minutes at -40 ° C and then 20 minutes at 125 ° C

Repeated cycle number: 1,000

-Adhesive strength -

Using each of the compositions from Examples 1 and 3 and Comparative Example 1, an adhesive test piece was prepared using the following method. That is, a thin coating of the composition was applied to the silver-plated copper foil, a 2 mm square wafer was placed on the composition, and heated by heating at 100 ° C for 1 hour and then at 150 ° C for 2 hours. The composition was cured, thereby completing the preparation of the adhesive test piece. The rupture of the prepared adhesive test piece was measured using a die bond strength tester (device name: Dage Series 4000 bond strength tester, test speed: 200 μm/s, test height: 10.0 μm, measurement temperature: 25 ° C) The adhesion strength.

As is apparent from the results in Tables 2 and 3, the cured product obtained from the composition of Comparative Example 1 lacking the component (B) exhibited poor flexural strength and heat discoloration resistance, in which the composition was discolored under light from the LED. Further, the cured product obtained from the composition containing the epoxy resin instead of the reference example of the component (B) undergoes yellowing after heating. In contrast, the cured product obtained from the composition of the examples of the present invention exhibited high hardness and did not substantially discolor. Further, it is apparent from the microhardness values listed in Table 2 that the composition of the examples produced hardness higher than that of the cured product obtained by curing the compositions of the comparative examples and the reference examples under the same conditions. The product is cured and also exhibits a faster cure rate.

Industrial applicability

The composition of the present invention cures quickly and produces a cured product exhibiting excellent heat discoloration resistance and excellent UV resistance, and thus is highly suitable for a resin which acts on a capsule-packaged optical element.

Fig. 1 shows a ²⁹ Si-NMR chart of the polyfluorene oxide resin obtained in Synthesis Example 1.

Claims (9)

A composition for encapsulating an optical semiconductor element, the composition comprising the components (A), (B), (C) and (D) described below: (A) a first polyoxyxene resin having The non-aromatic group containing an epoxy group is represented by the average composition formula (1) shown below, and the amount thereof is from 50 parts by mass to 90 parts by mass. Wherein R ¹ represents a non-aromatic group containing an epoxy group, and each R ² independently represents a member selected from the group consisting of a hydroxyl group, a C ₁ to C ₂₀ monovalent hydrocarbon group, and a C ₁ to C ₆ alkoxy group, each R ³ represents C ₁ to C ₂₀ monovalent hydrocarbon group, x and y each independently represent an integer of 0, 1 or 2, a represents a value in the range of 0.25 to 0.75, b represents a value in the range of 0.25 to 0.75, and c represents a value of 0 to a value in the range of 0.3, the constraint is a + b + c = 1, and n represents an integer from 2 to 20, and (B) a second polyoxyl resin having an epoxy group-containing non-aromatic group, The average composition formula (2) shown is in the range of 10 parts by mass to 50 parts by mass, Wherein R ¹ , R ² and R ³ are as defined above, each z independently represents an integer of 0, 1 or 2, d represents a value in the range from 0.5 to 0.8, and e represents a value in the range from 0.2 to 0.5, The limiting condition is d+e=1, (C) a curing agent having a functional group reactive with an epoxy group in an amount of all rings per one mole of the component (A) and the component (B) The oxy group provides 0.4 to 1.5 moles of the functional group reactive with the epoxy group, and (D) the curing catalyst in an amount of 0.01 mass per 100 parts by mass of the combination of the component (A) and the component (B). To the range of 3 parts by mass, wherein the epoxy equivalent of the component (A) is in the range of 200 g/mol to 800 g/mol, and the epoxy equivalent of the component (B) is less than the component (A) The epoxy equivalent is at least 30 g/mol. The composition of claim 1, wherein n in the average composition formula (1) is an integer from 3 to 20. The composition of claim 1, wherein the polystyrene equivalent average molecular weight of the component (A) is in the range of 3,000 to 10,000. The composition of claim 1, wherein R ¹ represents β-(3,4-epoxycyclohexyl)ethyl or γ-glycidoxyalkyl. The composition of claim 1, wherein R ³ is a methyl group. The composition of claim 1, wherein the epoxy equivalent of the component (A) is in the range of 300 g/mol to 600 g/mol, and the epoxy equivalent of the component (B) is from 250 g/mol to Within the range of 400 g/mol. The composition of claim 1, wherein component (C) is an acid anhydride. The composition of claim 1 further comprising a mercapto-based decane coupling agent. A semiconductor device comprising an optical semiconductor element and a cured product obtained by curing a composition according to any one of claims 1 to 8 and encapsulating the optical semiconductor element.