JP7270574B2 - Addition-curable silicone composition, cured silicone product, and optical element - Google Patents

Description

TECHNICAL FIELD The present invention relates to an addition-curable silicone composition, a cured silicone product thereof, and an optical element encapsulated with the cured silicone product.

A device having a light emitting diode (LED) as an optical semiconductor element generally has a configuration in which the LED mounted on a substrate is sealed with a sealing material made of a transparent resin. Epoxy resin has traditionally been used as this encapsulating material, but due to the recent miniaturization of semiconductor packages, the increase in the amount of heat generated due to the increased brightness of LEDs, and the shortening of the wavelength of light, the resin cracks and cracks. Yellowing occurred, leading to a decrease in reliability.

Therefore, from the viewpoint of heat resistance and heat discoloration resistance, attention is paid to silicone resin compositions as sealing materials, and addition reaction curing silicone resin compositions can be cured in a short time by heating, so productivity is high. , and is used as a sealing material for LEDs (Patent Document 1).

A high refractive index and resistance to sulfuration are required for LED encapsulating materials, and for such applications, silicone resin compositions having phenylsiloxane in the main skeleton (Patent Documents 2 and 3) have a high refractive index and It is known that a cured product having resistance to sulfurization can be provided.

However, conventional encapsulating materials using phenylsiloxane units do not have sufficient resistance to thermal shock, and problems such as peeling from the package and cracking of the resin occur.

Japanese Patent Application Laid-Open No. 2004-292714 JP 2005-105217 A JP 2010-132795 A

SUMMARY OF THE INVENTION It is an object of the present invention to provide an addition-curable silicone resin composition which gives a cured product having excellent resistance to thermal shock and resistance to vulcanization.

（式中、Ｒ^３は、それぞれ同一又は異なっていてもよい、炭素原子数１～８のアルキレン基を表し、Ｒ^４は、それぞれ同一又は異なっていてもよい、アルケニル基を含まない置換又は非置換の一価炭化水素基であり、破線は結合手を表す。）
（Ｂ）下記一般式（３）で表される直鎖状オルガノポリシロキサン、

（式中、Ｒ^５は、それぞれ同一又は異なっていてもよい、アルケニル基を含まない置換又は非置換の一価炭化水素基であり、Ｒ^６はメチル基又はフェニル基であり、ｈは０～５０の数であり、ｉは０～１００の数である。但し、ｈが０の時、Ｒ^６はフェニル基であり、かつ、ｉは１～１００の数である。ｈが付された括弧内にあるシロキサン単位及びｉが付された括弧内のシロキサン単位は、互いにランダムに配列していても、ブロックで配列していてもよい。）
（Ｃ）１分子中に少なくとも２個以上のケイ素原子結合水素原子を有する化合物：前記（Ａ）成分及び（Ｂ）成分中のケイ素原子結合アルケニル基１個に対して前記（Ｃ）成分中のケイ素原子結合水素原子の数が、０．１～５．０個となる量、
及び、
（Ｄ）白金族金属を含むヒドロシリル化触媒、
を含む付加硬化型シリコーン組成物を提供する。 In order to solve the above problems, in the present invention,
₍ A) Organopolysiloxane resin (R ¹³ SiO _1/2 ) _a ( ^{R 2} R ₁ ² SiO 1/2 ) _b (R ² R ₁ SiO _2/2 ) _c represented by the following general formula (1) (R ¹ ₂ SiO _2/2 ) _d (R ² SiO _3/2 ) _e (R ¹ SiO _3/2 ) _f (SiO _4/2 ) _g (O _2/2 Si(R ¹ )-X-Si( R ¹ ) O _2/2 ) _x (O _3/2 Si—X—SiO _3/2 ) _y (1)
(wherein each R ¹ is a substituted or unsubstituted monovalent hydrocarbon group containing no alkenyl group, which may be the same or different, at least 10 mol % of all R ¹ are aryl groups, and R ² is an alkenyl group, X is a divalent group represented by the following general formula (2), and a, b, c, d, e, f, g, x and y are each a≧0; , b≧0, c≧0, d≧0, e≧0, f≧0, g≧0, x≧0, y≧0, provided that b+c+e>0, e+f+g+y>0, x+y> 0 and a number that satisfies a+b+c+d+e+f+g+x+y=1.)

(In the formula, R ³ represents an alkylene group having 1 to 8 carbon atoms, which may be the same or different, and R ⁴ is a substituted or non-alkenyl group-free, which may be the same or different. It is a substituted monovalent hydrocarbon group, and the dashed line represents a bond.)
(B) a linear organopolysiloxane represented by the following general formula (3);

(wherein R ⁵ is a substituted or unsubstituted monovalent hydrocarbon group that does not contain an alkenyl group, which may be the same or different, R ⁶ is a methyl group or a phenyl group, and h is 0 to is a number of 50 and i is a number from 0 to 100. However, when h is 0, R ⁶ is a phenyl group and i is a number from 1 to 100. Brackets with h attached The siloxane units inside and the siloxane units in parentheses with i may be arranged randomly or in blocks.)
(C) a compound having at least two silicon-bonded hydrogen atoms in one molecule: for one silicon-bonded alkenyl group in the components (A) and (B), an amount such that the number of silicon-bonded hydrogen atoms is 0.1 to 5.0,
as well as,
(D) a hydrosilylation catalyst comprising a platinum group metal;
An addition curable silicone composition comprising:

With such an addition-curable silicone composition, a cured product having excellent thermal shock resistance and sulfuration resistance can be obtained.

（式中、破線は結合手を表す。） Moreover, it is preferable that said X in said (A) component is a divalent group represented by following formula (4).

(In the formula, broken lines represent bonds.)

With such a composition, the thermal shock resistance and sulfuration resistance of the cured product of the silicone composition can be enhanced.

Moreover, in the general formulas (1) and (3), R ¹ and R ⁵ are preferably phenyl groups or methyl groups.

If it is such, it can be used more suitably as the (A) component and the (B) component.

Moreover, in the general formula (1), it is preferable that the R ² R ¹ ₂ SiO _1/2 unit contains a siloxane unit represented by the following formula (5).

With such a composition, the strength, refractive index and resistance to vulcanization of the cured product of the silicone composition can be enhanced.

Moreover, it is preferable that the component (B) contains a siloxane unit represented by the formula (5).

With such a composition, the strength, refractive index, and resistance to vulcanization of the cured product of the silicone composition can be enhanced.

Furthermore, the present invention provides a silicone cured product, which is a cured product of the above addition-curable silicone composition.

Such a silicone cured product is excellent in thermal shock resistance and sulfuration resistance, so it is used as a coating material and sealing material for semiconductor elements, especially semiconductor elements for optical applications, and as a protective coating material for electrical and electronic applications. be able to.

Furthermore, the present invention provides an optical element encapsulated with the cured silicone product.

The cured silicone product of the present invention exhibits less peeling and cracking from the package due to thermal shock, and is excellent in resistance to sulfurization. Therefore, an optical element encapsulated with such a silicone cured product has high reliability.

As described above, the addition-curable silicone composition of the present invention can give a cured product that is less prone to peeling and cracking from the package due to thermal shock and that is excellent in resistance to sulfurization. Therefore, a cured product obtained from such an addition-curable silicone composition can be suitably used as an optical element encapsulating material.

As described above, an addition-curable silicone composition that gives a cured product with little peeling and cracking from the package against thermal shock and with excellent resistance to sulfurization, and highly reliable optics encapsulated by the cured product The development of the element was required.

As a result of intensive studies on the above problems, the inventors of the present invention have found that the above problems can be solved by an addition-curable silicone composition containing components (A), (B), (C) and (D), which will be described later. and completed the present invention.

（式中、Ｒ^３は、それぞれ同一又は異なっていてもよい、炭素原子数１～８のアルキレン基を表し、Ｒ^４は、それぞれ同一又は異なっていてもよい、アルケニル基を含まない置換又は非置換の一価炭化水素基であり、破線は結合手を表す。）
（Ｂ）下記一般式（３）で表される直鎖状オルガノポリシロキサン、

（式中、Ｒ^５は、それぞれ同一又は異なっていてもよい、アルケニル基を含まない置換又は非置換の一価炭化水素基であり、Ｒ^６はメチル基又はフェニル基であり、ｈは０～５０の数であり、ｉは０～１００の数である。但し、ｈが０の時、Ｒ^６はフェニル基であり、かつ、ｉは１～１００の数である。ｈが付された括弧内にあるシロキサン単位及びｉが付された括弧内のシロキサン単位は、互いにランダムに配列していても、ブロックで配列していてもよい。）
（Ｃ）１分子中に少なくとも２個以上のケイ素原子結合水素原子を有する化合物：前記（Ａ）成分及び（Ｂ）成分中のケイ素原子結合アルケニル基１個に対して前記（Ｃ）成分中のケイ素原子結合水素原子の数が、０．１～５．０個となる量、
及び、
（Ｄ）白金族金属を含むヒドロシリル化触媒、
を含む付加硬化型シリコーン組成物である。 That is, the present invention
₍ A) Organopolysiloxane resin (R ¹³ SiO _1/2 ) _a ( ^{R 2} R ₁ ² SiO 1/2 ) _b (R ² R ₁ SiO _2/2 ) _c represented by the following general formula (1) (R ¹ ₂ SiO _2/2 ) _d (R ² SiO _3/2 ) _e (R ¹ SiO _3/2 ) _f (SiO _4/2 ) _g (O _2/2 Si(R ¹ )-X-Si( R ¹ ) O _2/2 ) _x (O _3/2 Si—X—SiO _3/2 ) _y (1)
(wherein each R ¹ is a substituted or unsubstituted monovalent hydrocarbon group containing no alkenyl group, which may be the same or different, at least 10 mol % of all R ¹ are aryl groups, and R ² is an alkenyl group, X is a divalent group represented by the following general formula (2), and a, b, c, d, e, f, g, x and y are each a≧0; , b≧0, c≧0, d≧0, e≧0, f≧0, g≧0, x≧0, y≧0, provided that b+c+e>0, e+f+g+y>0, x+y> 0 and a number that satisfies a+b+c+d+e+f+g+x+y=1.)

(In the formula, R ³ represents an alkylene group having 1 to 8 carbon atoms, which may be the same or different, and R ⁴ is a substituted or non-alkenyl group-free, which may be the same or different. It is a substituted monovalent hydrocarbon group, and the dashed line represents a bond.)
(B) a linear organopolysiloxane represented by the following general formula (3);

(wherein R ⁵ is a substituted or unsubstituted monovalent hydrocarbon group that does not contain an alkenyl group, which may be the same or different, R ⁶ is a methyl group or a phenyl group, and h is 0 to is a number of 50 and i is a number from 0 to 100. However, when h is 0, R ⁶ is a phenyl group and i is a number from 1 to 100. Brackets with h attached The siloxane units inside and the siloxane units in parentheses with i may be arranged randomly or in blocks.)
(C) a compound having at least two silicon-bonded hydrogen atoms in one molecule: for one silicon-bonded alkenyl group in the components (A) and (B), an amount such that the number of silicon-bonded hydrogen atoms is 0.1 to 5.0,
as well as,
(D) a hydrosilylation catalyst comprising a platinum group metal;
An addition curable silicone composition comprising

The present invention will be described in detail below, but the present invention is not limited to these.

[Addition-curable silicone composition]
The addition-curable silicone composition of the present invention is an addition-curable silicone composition containing a branched organosiloxane having a silphenylene structure in its skeleton, wherein the following (A), (B), (C) and It contains component (D). Each component will be described in detail below.

（式中、Ｒ^３は、それぞれ同一又は異なっていてもよい、炭素原子数１～８のアルキレン基を表し、Ｒ^４は、それぞれ同一又は異なっていてもよい、アルケニル基を含まない置換又は非置換の一価炭化水素基であり、破線は結合手を表す。） <(A) Component>
Component (A) in the addition-curable silicone composition of the present invention is an organopolysiloxane resin represented by the following general formula (1).
( ^R13SiO1 _{/ 2} ) _a ( ^R2R12SiO1 _/ ² ) _b ( _R2R1SiO2 ^/ ₂ ) _c ( ^R12SiO2 _{/ 2} ) _d ⁽ R2SiO3 ^/ ₂ ) _e (R ¹ SiO _3/2 ) _f (SiO _4/2 ) _g (O _2/2 Si(R ¹ )—X—Si(R ¹ )O _2/2 ) _x (O _3/2 Si—X —SiO _3/2 ) _y (1)
(wherein each R ¹ is a substituted or unsubstituted monovalent hydrocarbon group containing no alkenyl group, which may be the same or different, at least 10 mol % of all R ¹ are aryl groups, and R ² is an alkenyl group, X is a divalent group represented by the following general formula (2), and a, b, c, d, e, f, g, x and y are each a≧0; , b≧0, c≧0, d≧0, e≧0, f≧0, g≧0, x≧0, y≧0, provided that b+c+e>0, e+f+g+y>0, x+y> 0 and a number that satisfies a+b+c+d+e+f+g+x+y=1.)

(In the formula, R ³ represents an alkylene group having 1 to 8 carbon atoms, which may be the same or different, and R ⁴ is a substituted or non-alkenyl group-free, which may be the same or different. It is a substituted monovalent hydrocarbon group, and the dashed line represents a bond.)

Component (A) is a necessary component for obtaining reinforcing properties of the cured product of the silicone composition, and contains either or both of SiO _3/2 units and SiO _4/2 units.

R ¹ is not particularly limited as long as it does not contain an alkenyl group. Examples include alkyl groups such as methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group and heptyl group; Cycloalkyl groups such as cyclohexyl group; Aryl groups such as phenyl group, tolyl group, xylyl group and naphthyl group; Aralkyl groups such as benzyl group and phenethyl group; Chloromethyl group, 3-chloropropyl group, 3,3,3- Examples include unsubstituted or halogen-substituted monovalent hydrocarbon groups usually having 1 to 12 carbon atoms, preferably 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, such as halogenated alkyl groups such as trifluoropropyl group. are preferred, and a methyl group is particularly preferred.

At least 10 mol % of all R ¹ are aryl groups. If the aryl group in all R ¹ is less than 10 mol %, it is impossible to improve the refractive index, improve the light extraction efficiency in the LED package, and provide sulfuration resistance for suppressing sulfurization of the silver substrate. Examples of the aryl group include phenyl group, tolyl group, xylyl group, naphthyl group and the like, with phenyl group being particularly preferred.

Also, R ¹ is preferably a phenyl group or a methyl group, and such groups can be more preferably used as the component (A).

R ² is an alkenyl group, preferably having 2 to 10 carbon atoms such as a vinyl group, an allyl group or an ethynyl group, more preferably an alkenyl group having 2 to 6 carbon atoms, and particularly preferably a vinyl group.

In addition, X is a divalent group represented by the general formula (2), R ³ is an alkylene group having 1 to 8 carbon atoms, preferably an ethylene group or a trimethylene group, more preferably an ethylene group. .

Examples of R ⁴ are the same as those of R ¹ , and preferably a methyl group.

（式中、破線は結合手を表す。） That is, X is preferably a divalent group represented by the following formula (4).

(In the formula, broken lines represent bonds.)

Component (A) preferably contains a siloxane unit in which the R ² R ¹ ₂ SiO _1/2 unit is represented by the following formula (5) in the above general formula (1), and the siloxane unit is contained in one molecule It is more preferable to have two or more. By having this, the strength and resistance to vulcanization of the cured product of the silicone composition can be enhanced.

If a, b, c, d, e, f, g, x and y in formula (1) are outside the above ranges, the cured product of the silicone composition of the present invention will have high hardness and resistance to sulfurization. cannot be given.

Component (A) is preferably a three-dimensional network organopolysiloxane resin that is waxy or solid at 23°C. The term "waxy" means a non-self-flowing gum-like substance (raw rubber-like) having a viscosity of 10,000 Pa·s or more, particularly 100,000 Pa·s or more, at 23°C.

Component (A) may be used alone or in combination of two or more.

（式中、Ｒ^５は、それぞれ同一又は異なっていてもよい、アルケニル基を含まない置換又は非置換の一価炭化水素基であり、Ｒ^６はメチル基又はフェニル基であり、ｈは０～５０の数であり、ｉは０～１００の数である。但し、ｈが０の時、Ｒ^６はフェニル基であり、かつ、ｉは１～１００の数である。ｈが付された括弧内にあるシロキサン単位及びｉが付された括弧内のシロキサン単位は、互いにランダムに配列していても、ブロックで配列していてもよい。） <(B) Component>
Component (B) is a linear organopolysiloxane represented by the following general formula (3).

(wherein R ⁵ is a substituted or unsubstituted monovalent hydrocarbon group that does not contain an alkenyl group, which may be the same or different, R ⁶ is a methyl group or a phenyl group, and h is 0 to is a number of 50 and i is a number from 0 to 100. However, when h is 0, R ⁶ is a phenyl group and i is a number from 1 to 100. Brackets with h attached The siloxane units inside and the siloxane units in parentheses with i may be arranged randomly or in blocks.)

Component (B) has two vinyl groups in one molecule and is a component that provides stress relaxation after curing of the silicone composition.

Examples of ^R5 are the same as those of ^R1 in the above component (A).

In general formula (3), h is an integer of 0-50, i is an integer of 0-100, and when h is 0, R ⁶ is a phenyl group and i is 1-100. If h and i are outside the above range, the cured product of the silicone composition of the present invention cannot be imparted with high hardness and resistance to sulfurization.

The viscosity of component (B) at 25° C. is preferably 10 to 100,000 mPa·s, more preferably 10 to 10,000 mPa·s. If the viscosity is within the above range, the target high hardness can be obtained without the possibility that this component acts as a soft segment more than necessary. In addition, there is no possibility that the viscosity of the composition becomes significantly high and the workability is deteriorated. In addition, unless otherwise specified below, the viscosity is a value measured by a rotational viscometer at 25°C. Although the rotational viscometer is not particularly limited, for example, BL type, BH type, BS type, and cone plate type can be used.

Component (B) preferably has a siloxane unit represented by the following formula (5) at its molecular terminal, and more preferably has the siloxane unit at both molecular terminals. By having this, the strength, refractive index, and resistance to vulcanization of the cured product of the silicone composition can be enhanced.

Specific examples of the component (B) include diphenylsiloxane endblocked with methylphenylvinyl groups at both ends, diphenylsiloxane endblocked with methylphenylvinyl groups at one end and diphenylvinyl groups at one end, diphenylsiloxane endblocked at both ends with diphenylvinyl groups, diphenylsiloxane endblocked at both ends with diphenylvinyl groups. Diphenylsiloxane/methylphenylsiloxane copolymer, both ends dimethylvinyl group-blocked diphenylsiloxane, one-end dimethylvinyl group one-end methylphenylvinyl group-blocked diphenylsiloxane, both ends dimethylvinyl group-blocked methylphenylsiloxane, one-end dimethylvinyl group piece A terminal methylphenylvinyl group-blocked methylphenylsiloxane and the like can be mentioned. Component (B) may be used alone or in combination of two or more.

The mixing ratio of components (A) and (B) is preferably in the range of 20:80 to 80:20 (A):(B). Within this range, it is possible to obtain a cured product having an excellent balance of physical properties such as strength and resistance to sulfurization.

<(C) Component>
Component (C) is a compound having at least two or more silicon-bonded hydrogen atoms in one molecule, which undergoes a hydrosilylation reaction with components (A) and (B) and acts as a cross-linking agent.

There are no particular restrictions on the molecular structure of component (C). For example, various conventionally produced organohydrogenpolysiloxanes and silicon-bonded hydrogen atoms, such as linear, cyclic, branched, and three-dimensional network structures can be used. Further, component (C) may be liquid, waxy or solid at 23°C.

From the viewpoint of compatibility with components (A) and (B), component (C) preferably has at least one aryl group or arylene group. Examples of the aryl group include those exemplified for the component (A), and examples of the arylene group include a phenylene group and a naphthylene group.

As component (C), for example, an organohydrogenpolysiloxane represented by the following average compositional formula (7) can be used.
^R7jHkSiO _{( 4-jk)/2 (} 7)
(In the formula, R ⁷ does not contain an alkenyl group and is the same or different from each other, unsubstituted or substituted, preferably having 1 to 12 carbon atoms, more preferably 1 to 10, still more preferably 1 to 8 is a monovalent hydrocarbon group bonded to a silicon atom, and is exemplified by the same as R ¹ in component (A) and R ⁵ in component (B), and j and k are preferably 0. .7 ≤ j ≤ 2.1, 0.001 ≤ k ≤ 1.0, and a positive number satisfying 0.8 ≤ j + k ≤ 3.0, more preferably 1.0 ≤ j ≤ 2.0 , 0.01≤k≤1.0 and 1.55≤j+k≤2.5.

The organohydrogenpolysiloxane has at least 2, preferably 3 to 300, particularly preferably 3 to 100 silicon-bonded hydrogen atoms (that is, hydrosilyl groups (SiH groups)) per molecule. When the organohydrogenpolysiloxane has a linear structure, these SiH groups may be located either at the end of the molecular chain or in the middle of the molecular chain (non-terminal of the molecular chain), or at both. may be

The organohydrogenpolysiloxane preferably has a siloxane unit represented by the following formula (6), and more preferably has two or more such siloxane units in one molecule. By having this, it becomes possible to impart high hardness and high resistance to sulfurization to the cured product of the silicone composition.

The number of silicon atoms in one molecule (degree of polymerization) of the organohydrogenpolysiloxane is preferably 2 to 300, more preferably 3 to 200, still more preferably 4 to 150.

Specific examples of organohydrogenpolysiloxanes include 1,1,3,3-tetramethyldisiloxane, 1,3,5,7-tetramethylcyclotetrasiloxane, tris(hydrogendimethylsiloxy)methylsilane, tris (hydrogendimethylsiloxy)phenylsilane, tris(hydrogenmethylphenylsiloxy)methylsilane, tris(hydrogenmethylphenylsiloxy)phenylsilane, methylhydrogencyclopolysiloxane, methylhydrogensiloxane/dimethylsiloxane cyclic copolymer, both Terminal trimethylsiloxy group-blocked methylhydrogenpolysiloxane, both terminal trimethylsiloxy group-blocked dimethylsiloxane/methylhydrogensiloxane copolymer, both terminal trimethylsiloxy group-blocked methylhydrogensiloxane/diphenylsiloxane copolymer, both terminal trimethylsiloxy groups Methylhydrogensiloxane/diphenylsiloxane/dimethylsiloxane copolymer blocked at both ends, methylhydrogensiloxane/methylphenylsiloxane/dimethylsiloxane copolymer blocked at both ends with trimethylsiloxy groups, dimethylpolysiloxane blocked at both ends with dimethylhydrogensiloxy groups, both ends dimethylhydrogensiloxy group-blocked diphenylpolysiloxane, both ends dimethylhydrogensiloxy group-blocked methylhydrogenpolysiloxane, both ends dimethylhydrogensiloxy group-blocked dimethylsiloxane/methylhydrogensiloxane copolymer, both ends dimethylhydrogensiloxy group Methylhydrogensiloxane/dimethylsiloxane/diphenylsiloxane copolymer blocked at both ends, methylhydrogensiloxane/dimethylsiloxane/methylphenylsiloxane copolymer blocked at both ends with dimethylhydrogensiloxy groups, dimethylpolysiloxane blocked at both ends with hydrogenmethylphenylsiloxy groups , diphenylpolysiloxane blocked with dimethylhydrogensiloxy groups at both ends, methylhydrogenpolysiloxane blocked with hydrogenmethylphenylsiloxy groups at both ends, dimethylsiloxane-methylhydrogensiloxane copolymer blocked with hydrogenmethylphenylsiloxy groups at both ends, both ends hydrogenmethylphenylsiloxy group-blocked methylhydrogensiloxane/dimethylsiloxane/diphenylsiloxane copolymer, hydrogenmethylphenylsiloxy group-blocked methylhydrogensiloxane/dimethylsiloxane/methylphenylsiloxane copolymer at both ends, (CH ₃ ) ₂ Copolymers consisting of HSiO _1/2 units, (CH ₃ ) ₃ SiO _1/2 units and SiO _4/2 units, copolymers consisting of (CH ₃ ) ₂ HSiO _1/2 units and SiO _4/2 units Examples thereof include coalescence, copolymers composed of (CH ₃ ) ₂ HSiO _1/2 units, SiO _4/2 units and (C ₆ H ₅ ) ₃ SiO _1/2 units.

As the compound having a silicon-bonded hydrogen atom, compounds represented by the following structural formulas can be used.

The amount of component (C) is such that the number of silicon-bonded hydrogen atoms in component (C) per silicon-bonded alkenyl group in components (A) and (B) is 0.1-5. 0, preferably in the range of 0.5 to 3.0, more preferably in the range of 0.5 to 2.0. If the amount of component (C) is outside the above range, it will be impossible to impart high hardness to the cured product of the silicone composition.

The (C) component organohydrogenpolysiloxane may be used alone or in combination of two or more.

<(D) Component>
Component (D), a hydrosilylation catalyst containing a platinum group metal, should promote the addition reaction between the alkenyl groups in components (A) and (B) and the silicon-bonded hydrogen atoms in component (C). Any catalyst may be used. Specific examples thereof include platinum group metals such as platinum, palladium and rhodium, chloroplatinic acid, alcohol-modified chloroplatinic acid, coordination compounds of chloroplatinic acid and olefins, vinylsiloxanes or acetylene compounds, tetrakis (triphenylphosphine ) palladium, chlorotris(triphenylphosphine)rhodium, and other platinum group metal compounds, with platinum compounds being particularly preferred.

Component (D) may be used singly or in combination of two or more.

The amount of component (D) to be blended may be an effective amount as a catalyst. It is preferably in the range of 500 ppm, more preferably in the range of 1-100 ppm. Within this range, the reaction rate of the addition reaction is appropriate, and a cured product having high strength can be obtained.

<Other ingredients>
Components such as adhesion improvers and reaction inhibitors may be added to the addition-curable silicone composition of the present invention, depending on the purpose.

From the viewpoint of imparting self-adhesiveness to the composition of the present invention, which is an addition reaction curing type, the adhesiveness improver includes organic silicon compounds such as silanes and siloxanes containing functional groups that impart adhesiveness, and non-silicone compounds. An organic compound or the like is used.

Specific examples of functional groups that impart adhesiveness include alkenyl groups such as vinyl groups and allyl groups bonded to silicon atoms, or hydrogen atoms; epoxy groups bonded to silicon atoms via carbon atoms (eg, γ-glycide xypropyl group, β-(3,4-epoxycyclohexyl)ethyl group, etc.), acryloxy group (eg, γ-acryloxypropyl group, etc.), or methacryloxy group (eg, γ-methacryloxypropyl group, etc.); alkoxysilyl Groups (for example, alkoxysilyl groups such as trimethoxysilyl groups, triethoxysilyl groups, methyldimethoxysilyl groups bonded to silicon atoms via alkylene groups which may contain 1 to 2 ester structures, urethane structures, and ether structures group, etc.).

Examples of organosilicon compounds containing functional groups that impart adhesiveness include silane coupling agents, siloxanes having alkoxysilyl groups and organic functional groups, and compounds in which alkoxysilyl groups are introduced into organic compounds having reactive organic groups. is exemplified.

Examples of non-silicone organic compounds include allyl esters of organic acids, epoxy ring-opening catalysts, organic titanium compounds, organic zirconium compounds, and organic aluminum compounds.

Examples of reaction inhibitors include phosphorus-containing compounds such as triphenylphosphine; nitrogen-containing compounds such as tributylamine, tetramethylethylenediamine and benzotriazole; sulfur-containing compounds; acetylenic compounds; hydroperoxy compounds; maleic acid derivatives; Cyclohexanol, 3,5-dimethyl-1-hexyn-3-ol, ethynylmethyldecylcarbinol, 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane, etc. Known compounds having a curing inhibitory effect on the hydrosilylation catalyst of component (D) are exemplified.

Since the degree of the curing inhibitory effect of the reaction inhibitor varies depending on the chemical structure of the reaction inhibitor, it is desirable to adjust the amount of the reaction inhibitor to an optimum amount for each reaction inhibitor to be used. Preferably, it is 0.001 to 5 parts by mass per 100 parts by mass of components (A), (B), (C) and (D). If the blending amount is 0.001 parts by mass or more, the long-term storage stability of the composition at room temperature can be sufficiently obtained. If the blending amount is 5 parts by mass or less, there is no possibility that the curing of the composition will be inhibited.

In addition, the composition of the present invention contains inorganic fillers such as finely powdered silica, crystalline silica, hollow fillers and silsesquioxane, and organoalkoxysilanes containing these fillers in order to improve the reinforcing properties of the composition of the present invention. compounds, organosilicon compounds such as organochlorosilane compounds, organosilazane compounds, low-molecular-weight siloxane compounds, fillers subjected to surface hydrophobizing treatment with organosilicon compounds; silicone rubber powders, silicone resin powders, etc. may be blended.

The finely divided silica preferably has a specific surface area (BET method) of 50 m ² /g or more, more preferably 50 to 400 m ² /g, particularly preferably 100 to 300 m ² /g. If the specific surface area is 50 m ² /g or more, sufficient reinforcing properties can be imparted to the cured product.

As such finely divided silica, known substances conventionally used as reinforcing fillers for silicone rubber can be used. For example, fumed silica (dry silica), precipitated silica (wet silica) and the like can be used. mentioned. The finely divided silica may be used as it is, but in order to impart good fluidity to the composition, it may be added with methylchlorosilanes such as trimethylchlorosilane, dimethyldichlorosilane, methyltrichlorosilane, dimethylpolysiloxane, hexamethyldisilazane, divinyl It is preferable to use one treated with an organic silicon compound such as tetramethyldisilazane, hexaorganodisilazane such as dimethyltetravinyldisilazane. Such reinforcing silica may be used singly or in combination of two or more.

[Silicone cured product]
Furthermore, the present invention provides a cured product (cured silicone product) obtained by curing the addition-curable silicone composition.

As the curing method and conditions for the silicone composition of the present invention, known curing methods and conditions can be employed. For example, it can be cured at 100 to 180° C. for 10 minutes to 5 hours.

The cured silicone product obtained by curing the addition-curable silicone composition of the present invention does not crack or warp when exposed to light, exhibits little decrease in light transmittance, and exhibits excellent light transmittance, heat resistance, and Since it is excellent in light resistance and sulfuration resistance, it can be used as a coating material or sealing material for semiconductor elements, particularly semiconductor elements for optical applications, and as a protective coating material for electrical and electronic applications.

[Optical element]
Furthermore, the present invention provides an optical element encapsulated with the cured silicone product.

As described above, the cured silicone product of the present invention exhibits less peeling and cracking from the package due to thermal shock, and is excellent in resistance to sulfurization. Therefore, an optical element encapsulated with such a silicone cured product has high reliability.

EXAMPLES The present invention will be specifically described below using Synthesis Examples, Examples, and Comparative Examples, but the present invention is not limited to these. The molecular weight is a standard polystyrene-equivalent number-average molecular weight in gel permeation chromatography (GPC), and the viscosity is a value at 25° C. measured using a rotational viscometer.

Ｔ_１：下記構造式（９）で表されるシロキサン単位

The abbreviations of the siloxane units have the following meanings.
^MViΦ : _{( CH3} )( _CH2 =CH)( _C6H5 )SiO1 _/2
D ^Φ : (C ₆ H ₅ ) ₂ SiO _2/2
Q: SiO _4/2
D ¹ : a siloxane unit represented by the following structural formula (8)

T ₁ : a siloxane unit represented by the following structural formula (9)

[Synthesis Example 1]
97 g of 1,4-bis(dimethylsilyl)benzene and 264 g of vinylmethyldimethoxysilane were dissolved in 40 g of toluene, 0.17 g of a 5% Pt—C catalyst was added, and the mixture was stirred at 80° C. for 5 hours. After the reaction, 2.3 g of activated carbon was added, and the mixture was stirred at 25°C for 1 hour and then filtered. The filtrate was distilled under reduced pressure under conditions of 100° C. and 10 mmHg or less for 2 hours to remove toluene and unreacted substances, thereby obtaining a compound represented by the following structural formula (10).

[Synthesis Example 2]
97 g of 1,4-bis(dimethylsilyl)benzene and 272 g of vinyltrimethoxysilane were dissolved in 40 g of toluene, 0.17 g of a 5% Pt—C catalyst was added, and the mixture was stirred at 80° C. for 5 hours. After the reaction, 2.3 g of activated carbon was added, and the mixture was stirred at 25°C for 1 hour and then filtered. The filtrate was distilled under reduced pressure under conditions of 100° C. and 10 mmHg or less for 2 hours to remove toluene and unreacted substances, thereby obtaining a compound represented by the following structural formula (11).

[Synthesis Example 3]
48.5 g of the compound obtained in Synthesis Example 1, 91.5 g of diphenyldimethoxysilane, 31.0 g of 1,3-dimethyl-1,3-diphenyl-1,3-divinyldisiloxane and [(OCH ₃ ) ₃ SiO _{1 /2} ] ₂ [(OCH ₃ ) ₂ SiO] ₂ was dissolved in 20 g of isopropanol, 2.6 g of methanesulfonic acid was added while stirring, and 23.5 g of water was added dropwise. . Then, 100 g of xylene was added and stirred at 70° C. for 5 hours. 6 g of a 50% aqueous potassium hydroxide solution was added, and the mixture was reacted at 120°C for 5 hours while distilling off the alcohol. was distilled off under reduced pressure for 2 hours under conditions of 100 ° C. and 10 mmHg or less to remove xylene and unreacted substances, and an organopolysiloxane resin that was solid at 23 ° C. (molecular weight: 1,750, structural unit ratio: M ^ViΦ _0.2 D ^Φ _0.37 Q _0.33 D ¹ _0.1 and vinyl group content: 0.091 mol/100 g).

[Synthesis Example 4]
In Synthesis Example 3, a solid organopolysiloxane resin (molecular weight: 1,250 , ^structural unit ratio: ^{MViΦ0.21DΦ0.39Q0.35D10.05} , vinyl _{group amount} : 0.086mol _/ ^100g ) _.

[Synthesis Example 5]
In the same procedure as in Synthesis Example 3, except that 26.4 g of the compound obtained in Synthesis Example 2 was used in place of the compound obtained in Synthesis Example 1, an organopolysiloxane that was solid at 23 ° C. A resin (molecular weight _: 2,600, structural ^unit _ratio : ^{MViΦ0.21DΦ0.39Q0.35T10.05} , vinyl group _weight : 0.085mol/ ^100g ) was obtained _.

[Synthesis Example 6]
The reaction product of hexachloroplatinic acid and 1,3-divinyltetramethyldisiloxane is mixed with methylphenylorgano with a viscosity of 700 mPa s containing 30 mol% of phenyl groups so that the platinum content is 1.0% by mass. A platinum catalyst was prepared by diluting with polysiloxane.

[Examples 1-4, Comparative Examples 1-2]
An addition-curable silicone composition was prepared by mixing the following ingredients in the amounts shown in Table 1. In addition, the numerical value of each component in Table 1 represents a mass part. The [Si-H]/[Si-Vi] value represents the molar ratio of silicon-bonded hydrogen atoms in component (C) to all silicon-bonded alkenyl groups in components (A) and (B). .

(A-1) Component:
Organopolysiloxane resin (A-2) component obtained in Synthesis Example 3:
Organopolysiloxane resin (A-3) component obtained in Synthesis Example 4:
Organopolysiloxane resin (A-4) component obtained in Synthesis Example 5:
Organopolysiloxane resin having a structural unit ratio: M ^ViΦ _0.20 D ^Φ _0.38 Q _0.42 and a vinyl group amount: 0.16 mol/100 g

(B) Component:
A linear organopolysiloxane represented by M ^ViΦ ₂ D ^Φ ₃ , having a viscosity of 2,000 mPa·s and a vinyl group content of 0.22 mol/100 g

(C-1) Component:
Organohydrogenpolysiloxane (C-2) component represented by (H(CH ₃ )(C ₆ H ₅ )SiO _1/2 ) ₃ ((C ₆ H ₅ )SiO _3/2 ) ₁ : the following structural formula Compound represented by (12)

（Ｆ－２）接着性向上剤：下記構造式（１４）で表される化合物

Component (D): The platinum catalyst obtained in Synthesis Example 6 and other components:
(E) reaction inhibitor: ethynylcyclohexanol (F-1) adhesion improver: compound represented by the following structural formula (13)

(F-2) Adhesion improver: a compound represented by the following structural formula (14)

The addition-curable silicone compositions obtained in Examples 1-4 and Comparative Examples 1-2 were subjected to the following evaluations, and the results are shown in Table 2.

[exterior]
Each composition was cured by heating at 150° C. for 4 hours, and the appearance of the resulting cured product was visually observed.

[Hardness]
Each composition was poured into a mold so as to have a thickness of 2 mm and cured under conditions of 150° C. for 4 hours. The Type D hardness of the cured product was measured according to JIS K6253-3:2012. If the Type D hardness is 50 or more, it can be determined that the material has sufficiently high hardness.

[Production of optical semiconductor package (PKG)]
As an LED package substrate, an LED package substrate [SMD5050 (I-CHIUN PRECISION INDUSTRY Co., Ltd.)], and EV-B35A (manufactured by SemiLEDs) was prepared as an optical semiconductor element.

Using a die bonder (AD-830 manufactured by ASM), a die bonding material KER-3000-M2 manufactured by Shin-Etsu Chemical Co., Ltd. is quantitatively transferred by stamping to the silver-plated first lead of the package substrate, and light is applied thereon. Equipped with a semiconductor device. Next, the package substrate was placed in an oven, the die bonding material was cured by heating (150° C., 2 hours), and the lower electrode of the optical semiconductor element and the first lead were electrically connected. Next, using a wire bonder, the LED package substrate on which the optical semiconductor element was mounted was electrically connected to the upper electrode and the second lead of the optical semiconductor element using a gold wire (FA 25 μm manufactured by Tanaka Denshi Kogyo Co., Ltd.). were connected to each other, and one package substrate for LED on which the optical semiconductor element was mounted was obtained.

[Thermal shock resistance]
The composition was sealed in a prescribed PKG and cured under conditions of 150° C.×4 hours. Using a liquid phase thermal shock tester (TSB-21, manufactured by Espec), the test was carried out under the test conditions of −40 ⇔ 125° C. and 5 minutes at each temperature. A fixed number of cycles were repeated, and the number of cycles up to the occurrence of any failure such as resin peeling from the PKG, resin cracks, or wire disconnection is shown. The higher the number of cycles, the better the composition in terms of thermal shock resistance.

[Sulfurization resistance]
The composition was sealed in a prescribed PKG and cured under conditions of 150° C.×4 hours. Next, 0.1 g of sulfur powder was put into a 100 g bottle, and the resin-encapsulated PKG was put into the bottle and sealed. After 48 hours at 70° C., the PKG was taken out and the color of the silver substrate was visually observed to determine the resistance to sulfurization. If the silver substrate of PKG was discolored black, it was evaluated as x, and if it was not discolored, it was evaluated as ◯.

As shown in Table 2, the cured silicone products of Examples 1-4 have good optical properties and mechanical properties. In addition, although the resistance to sulfurization is excellent, the resistance to thermal shock is not defective for 1,000 cycles or more, and is superior to the comparative examples. That is, it was confirmed that both sulfurization resistance and thermal shock resistance could be achieved.

In Comparative Example 1, since the (A) component did not contain silphenylene, which is an essential component of the present invention, the resistance to sulfurization was excellent, but the thermal shock resistance was much shorter than the endurance cycle of the Examples. In Comparative Example 2, a higher number of endurance cycles of thermal shock resistance than in Comparative Example 1 was obtained, but the silver substrate was discolored in the sulfurization resistance test, resulting in poor resistance to sulfurization.

From the above, it can be concluded that the addition-curable silicone composition of the present invention is superior in resistance to sulfurization and thermal shock to conventional encapsulants for LEDs, coating materials for optical semiconductor elements, and electrical and electronic applications. It has proven to be suitable as a protective coating material.

It should be noted that the present invention is not limited to the above embodiments. The above-described embodiment is an example, and any device having substantially the same configuration as the technical idea described in the claims of the present invention and exhibiting the same effect is the present invention. included in the technical scope of

Claims (6)

₍ A) Organopolysiloxane resin (R ¹³ SiO _1/2 ) _a ( ^{R 2} R ₁ ² SiO 1/2 ) _b (R ² R ₁ SiO _2/2 ) _c represented by the following general formula (1) (R ¹ ₂ SiO _2/2 ) _d (R ² SiO _3/2 ) _e (R ¹ SiO _3/2 ) _f (SiO _4/2 ) _g (O _2/2 Si(R ¹ )-X-Si( R ¹ ) O _2/2 ) _x (O _3/2 Si—X—SiO _3/2 ) _y (1)
(wherein each R ¹ is a substituted or unsubstituted monovalent hydrocarbon group containing no alkenyl group, which may be the same or different, at least 10 mol % of all R ¹ are aryl groups, and R ² is an alkenyl group, X is a divalent group represented by the following general formula (2), and a, b, c, d, e, f, g, x and y are each a≧0; , b>0 , c≧0, d≧0, e≧0, f≧0, g≧0, x≧0, y≧0, provided that b+c+e>0, e+f+g+y>0, x+y> 0 and a number that satisfies a+b+c+d+e+f+g+x+y=1.)

(In the formula, R ³ represents an alkylene group having 1 to 8 carbon atoms, which may be the same or different, and R ⁴ is a substituted or non-alkenyl group-free, which may be the same or different. It is a substituted monovalent hydrocarbon group, and the dashed line represents a bond.)
(B) a linear organopolysiloxane represented by the following general formula (3);

(wherein R ⁵ is a substituted or unsubstituted monovalent hydrocarbon group that does not contain an alkenyl group, which may be the same or different, R ⁶ is a methyl group or a phenyl group, and h is 0 to is a number of 50 and i is a number from 0 to 100. However, when h is 0, R ⁶ is a phenyl group and i is a number from 1 to 100. Brackets with h attached The siloxane units inside and the siloxane units in parentheses with i may be arranged randomly or in blocks.)
(C) a compound having at least two silicon-bonded hydrogen atoms in one molecule: for one silicon-bonded alkenyl group in the components (A) and (B), an amount such that the number of silicon-bonded hydrogen atoms is 0.1 to 5.0,
as well as,
(D) a hydrosilylation catalyst comprising a platinum group metal;
comprising
An addition-curable silicone composition, wherein the R ² R ¹² SiO _1/2 unit in the general formula (1) contains a siloxane unit represented by the following formula (5 ₎ .

2. The addition-curable silicone composition according to claim 1, wherein X is a divalent group represented by the following formula (4).

(In the formula, broken lines represent bonds.) 3. The addition-curable silicone composition according to claim 1, wherein ^R1 and ^R5 in the general formulas (1) and (3) are phenyl groups or methyl groups. 4. The addition-curable silicone composition according to any one of claims 1 to 3 , wherein the component (B) contains a siloxane unit represented by the following formula (5).

A cured silicone product, which is a cured product of the addition-curable silicone composition according to any one of claims 1 to 4 . An optical element sealed with the silicone cured product according to claim 5 .