JP7014745B2 - Additive curable silicone resin composition and optical element - Google Patents

Description

The present invention relates to an addition-curing silicone resin composition and an optical element, and in particular, an addition-curing type that provides a cured product having good rubber properties and strength characteristics, having a low refractive index in visible light, and having excellent product reliability. The present invention relates to a silicone resin composition and an optical element sealed with a cured product of the composition.

The addition-curable silicone composition contains an organopolysiloxane containing an addition-reactive carbon-carbon double bond and an organosilicon compound having a hydrogen atom bonded to silicon, and is cured by a hydrosilylation reaction to give a cured product. The cured product thus obtained has excellent heat resistance, cold resistance, and electrical insulation, and is transparent, so that it is used in various optical applications such as LED encapsulation materials. (Patent Document 1, Patent Document 2)

The addition-curable silicone composition used for optical applications and the encapsulant for an optical element made of the composition are required to have high transparency, and in order to achieve this, dimethyl is used in the main skeleton as having a high refractive index. Organopolysiloxane having a siloxane / diphenylsiloxane copolymer or polymethylphenylsiloxane has been commonly used.

Therefore, in Patent Document 3, an addition-curable silicone composition and a composition thereof that provide a cured product having a low refractive index and good transparency and light transmittance by containing fluorine from the viewpoint of light extraction efficiency. We have proposed a sealing material for optical elements made of.

However, in recent years, further lowering the refractive index has been required from the viewpoint of increasing the functionality of the optical element, and when the cured product of the addition-curable silicone composition has a lower refractive index than before, the resin strength becomes higher. There is a problem that it becomes brittle, its tensile strength is lowered, and when it is used as a sealing material for an optical element, cracks are likely to occur and the reliability of the optical package is lowered.

Japanese Unexamined Patent Publication No. 2004-186168 Japanese Unexamined Patent Publication No. 2004-143361 Japanese Unexamined Patent Publication No. 2013-010881

The present invention has been made in view of the above circumstances, and is a cured product having good rubber properties and strength characteristics, having a lower refractive index in visible light than before, and having a low refractive index and excellent product reliability. It is an object of the present invention to provide an addition-curable silicone resin composition and an optical element sealed with a cured product of the composition.

In order to solve the above problems, in the present invention,
(A) A linear chain having two or more silicon atom-bonded aliphatic unsaturated groups and one or more silicon atom-bonded CF _3- (CF ₂ ) _m- (CH ₂ ) _n- group in one molecule. A certain organopolysiloxane (where m is an integer of 0 or more and n is an integer of 1 or more) 0 parts by mass or more and less than 50 parts by mass,
(B) One molecule has two or more silicon atom-bonded aliphatic unsaturated groups and one or more silicon atom-bonded CF _3- (CF ₂ ) _o- (CH ₂ ) _p -group, and SiO Organopolysiloxane having a siloxane unit represented by _4/2 (where o is an integer of 5 or more and p is an integer of 1 or more) more than 50 parts by mass and less than 100 parts by mass,
(However, the total of the component (A) and the component (B) is 100 parts by mass.)
(C) An organic silicon compound having two or more silicon atom-bonded hydrogen atoms in one molecule: the molar ratio of the total aliphatic unsaturated group of the components (A) and (B) to the SiH group of the component (C). However, 0.2 ≤ SiH group / aliphatic unsaturated group ≤ 5.0,
(D) Platinum group metal catalyst: effective amount,
Provided is an addition-curable silicone resin composition characterized by containing the above.

Such an addition-curable silicone resin composition of the present invention has good rubber-like properties and strength characteristics, has a lower refractive index in visible light than before, and has high transparency, low refractive index, and high strength. It can provide a cured product with excellent product reliability and is suitable for optical applications.

At this time, the component (C) further has one or more silicon atom-bonded CF _3- (CF ₂ ) _q- (CH ₂ ) _r -groups in one molecule (where q is an integer of 0 or more). , R is an integer of 1 or more.).

As described above, if the CF _3- (CF ₂ ) _q- (CH ₂ ) _r -group is introduced into the component (C), the refractive index can be further reduced.

Further, it is preferable that the addition-curable silicone resin composition is cured to give a cured product having a refractive index (25 ° C.) of visible light (589 nm) of 1.37 or less.

With such a thing, visible light at 25 ° C., particularly light transmittance at a wavelength of 400 nm can be made excellent, and light extraction efficiency can also be made excellent.

Further, it is preferable that the addition-curable silicone resin composition is cured to give a cured product having a light transmittance of 80% or more at a wavelength of 300 to 800 nm at 25 ° C. in a layered state having a thickness of 2 mm.

With such a case, the visible light at 25 ° C., particularly the light transmittance at a wavelength of 400 nm can be more reliably improved, and the light extraction efficiency can also be improved.

Further, the addition-curable silicone resin composition preferably has a tensile strength of 0.5 MPa or more after curing.

If it is such a thing, it will have particularly good rubber-like properties and strength properties.

Further, it is preferable that the addition-curable silicone resin composition is for encapsulating an optical element.

The addition-curable silicone resin composition of the present invention can be particularly preferably used for encapsulating an optical element.

The present invention also provides an optical element sealed with a cured product of the above-mentioned silicone resin composition.

Such an optical element has good rubber-like properties and strength characteristics, has a lower refractive index in visible light than before, and has excellent product reliability with high transparency, low refractive index, and high intensity. Since the addition-curable silicone resin composition that can give a cured product is used, the reliability is excellent.

The addition-curable silicone resin composition of the present invention has good rubber-like properties and strength characteristics, and has a lower refractive index in visible light than before, and has high transparency, low refractive index, and high strength. It can provide an excellent cured product and is suitable for optical applications.

It is a schematic sectional drawing which shows an example (light emitting semiconductor device) of the optical element of this invention.

Hereinafter, the present invention will be described in detail.

As described above, in recent years, from the viewpoint of improving the functionality of optical elements, there is a demand for further lowering the refractive index of the cured product of the additive-curable silicone resin composition, but both the low refractive index and the strength are required. It was difficult to make it good.

As a result of diligent studies, the present inventors have made two or more silicon atom-bonded aliphatic unsaturated groups and one or more silicon atom-bonded CF _3- (CF ₂ ) _o- (CH ₂ ) in one molecule. Two organopolysiloxanes (where o is an integer of 5 or more and p is an integer of 1 or more) having a _p -group and a siloxane unit represented by SiO _4/2 in one molecule. A linear organopolysiloxane having the above silicon atom-bonded aliphatic unsaturated group and one or more silicon atom-bonded CF _3- (CF ₂ ) _m- (CH ₂ ) _n- group (where m is 0). We have found that a highly transparent, low-refractive-index and high-strength silicone cured product can be obtained by introducing the above-mentioned integer and n at a ratio larger than 1), and have reached the present invention.

That is, the present invention
(A) A linear chain having two or more silicon atom-bonded aliphatic unsaturated groups and one or more silicon atom-bonded CF _3- (CF ₂ ) _m- (CH ₂ ) _n- group in one molecule. A certain organopolysiloxane (where m is an integer of 0 or more and n is an integer of 1 or more) 0 parts by mass or more and less than 50 parts by mass,
(B) One molecule has two or more silicon atom-bonded aliphatic unsaturated groups and one or more silicon atom-bonded CF _3- (CF ₂ ) _o- (CH ₂ ) _p -group, and SiO Organopolysiloxane having a siloxane unit represented by _4/2 (where o is an integer of 5 or more and p is an integer of 1 or more) more than 50 parts by mass and less than 100 parts by mass,
(However, the total of the component (A) and the component (B) is 100 parts by mass.)
(C) An organic silicon compound having two or more silicon atom-bonded hydrogen atoms in one molecule: the molar ratio of the total aliphatic unsaturated group of the components (A) and (B) to the SiH group of the component (C). However, 0.2 ≤ SiH group / aliphatic unsaturated group ≤ 5.0,
(D) Platinum group metal catalyst: effective amount,
It is an addition curable silicone resin composition characterized by containing.

Such an addition-curable silicone resin composition of the present invention has good rubber-like properties and strength characteristics, has a lower refractive index in visible light than before, and has high transparency, low refractive index, and high strength. It can provide a cured product with excellent product reliability and is suitable for optical applications.

[Additionally curable silicone resin composition]
The addition-curable silicone resin composition of the present invention contains the following components (A) to (D).

<Ingredient (A)>
The component (A) is a direct element having two or more silicon atom-bonded aliphatic unsaturated groups and one or more silicon atom-bonded CF _3- (CF ₂ ) _m- (CH ₂ ) _n- group in one molecule. It is a chain-like organopolysiloxane (where m is an integer of 0 or more and n is an integer of 1 or more).

（式中、Ｒ^１は脂肪族不飽和基、Ｒ^２は脂肪族不飽和基以外の炭素数１～８の置換又は非置換の一価炭化水素基、Ｒｆ^１はＣＦ_３－（ＣＦ_２）_ｍ－（ＣＨ_２）_ｎ－基（ただし、ｍは０以上の整数、ｎは１以上の整数である。）であり、ａは１～３の整数、ｘ、ｙ、ｚは、それぞれｘ≧０、ｙ≧１、ｚ≧０の整数である。式中、Ｒ^１、Ｒ^２が複数ある場合には、それぞれ同一でも異なっていてもよい。） As the organopolysiloxane of the component (A), for example, the organopolysiloxane represented by the following general formula (1) is preferable.

(In the formula, R ¹ is an aliphatic unsaturated group, R ² is a substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms other than the aliphatic unsaturated group, and Rf ¹ is CF _3- (CF ₂ ). _m- (CH ₂ ) _n -group (where m is an integer of 0 or more and n is an integer of 1 or more), a is an integer of 1 to 3, and x, y, and z are x ≧, respectively. It is an integer of 0, y ≧ 1, and z ≧ 0. When there are a plurality of R ¹ and R ² in the formula, they may be the same or different from each other.)

In the above general formula (1), the alkenyl group is preferable as the aliphatic unsaturated group of R ¹ , and the alkenyl group having 2 to 10 carbon atoms such as a vinyl group, an allyl group and an ethynyl group, particularly 2 to 6 is preferable. But vinyl groups are preferred.

Alkyl groups such as methyl group, ethyl group, propyl group and butyl group, cyclohexyl group, cyclopentyl group and the like can be used as substituted or unsubstituted monovalent hydrocarbons having 1 to 8 carbon atoms other than the aliphatic unsaturated group of ^R2 . Examples thereof include aryl groups such as cycloalkyl groups, phenyl groups, trill groups, and xylyl groups, aralkyl groups such as benzyl groups and phenylethyl groups, and halogenated hydrocarbon groups such as chloromethyl groups, chloropropyl groups, and chlorocyclohexyl groups. To. An unsubstituted monovalent hydrocarbon group having 1 to 6 carbon atoms is preferable, and a methyl group is particularly preferable.

Rf ¹ is defined by CF _3- (CF ₂ ) _m- (CH ₂ ) _n -group (m is an integer of 0 or more, n is an integer of 1 or more), and m is preferably an integer satisfying 0≤m≤9. And n is preferably an integer satisfying 1 ≦ n ≦ 10. When there are a plurality of Rf ^1s (when y is 2 or more), they may be the same group or different groups.
In the present invention, CF _3- (CH ₂ ) _2- , CF _3- (CF ₂ ) _3- (CH ₂ ) _2- , CF _3- (CF ₂ ) _5- (CH ₂ ) are particularly preferable from the viewpoint of synthesis. ) ₂ -Group.

Further, in the above general formula (1), x is an integer of 0 or more, preferably an integer of 0 to 50, and y is an integer of 1 or more, preferably 2 to 5,000, and more preferably 5 to 1. It is an integer of 000. z is an integer of 0 or more, preferably an integer of 0 to 10,000, and more preferably an integer of 0 to 5,000. x + y + z is preferably 5 to 10,000, more preferably 5 to 1,000, and particularly preferably 5 to 100. The value of y / (x + y + z) is preferably in the range of 1/50 to 1/1, more preferably 1/10 to 1/1, and particularly preferably 1/5 to 1/1.

The organopolysiloxane of the component (A) preferably has a viscosity at 25 ° C. of 100 to 10,000,000 mPa · s or less, particularly preferably in the range of 200 to 10,000 mPa · s. These organopolysiloxanes can be used alone or in combination of two or more. The viscosity is the viscosity measured by a rotational viscometer.

（式中、Ｒ^１、Ｒ^２、Ｒｆ^１、ａは前記の通りである。） The organopolysiloxane of the component (A) can be produced by a method known per se. For example, the cyclotrisiloxane represented by the following general formula (i), the cyclotrisiloxane represented by the following general formula (ii), the organosiloxane represented by the following general formula (iii), and, if necessary, the following general formula ( It can be obtained by copolymerizing with cyclotrisiloxane represented by iv) in the presence of an alkali or acid catalyst.

(In the formula, R ¹ , R ² , R f ¹ , and a are as described above.)

<Ingredient (B)>
The component (B) is a component for obtaining reinforcing properties while maintaining the transparency of the cured product of the addition-curable silicone resin composition, and two or more silicon atom-bonded aliphatic unsaturated substances in one molecule. Organopolysiloxane having a group and one or more silicon atom-bonded CF _3- (CF ₂ ) _o- (CH ₂ ) _p -group and having a branched structure in siloxane units represented by SiO _4/2 (however, o is an integer of 5 or more, and p is an integer of 1 or more.) (B) If the CF _3- (CF ₂ ) o- (CH ₂ ) _p -group _o in the component is smaller than 5, the refractive index cannot be sufficiently lowered.

Examples of the silicon atom-bonded aliphatic unsaturated group include the same group as the above-mentioned ^R1 aliphatic unsaturated group described in the component (A).

The organopolysiloxane of the component (B) has a branched structure. The organopolysiloxane of the component (B) requires a branched structure consisting of _4/2 units of SiO, but further R ³ ₂ SiO _2/2 such as methyl vinyl syloxy units and dimethyl syloxy units, dimethyl vinyl syroxy units, and trimethyl. It may contain R ³ ₃ SiO _1/2 units such as syroxy units (in the formula, R ³ is a substituted or unsubstituted monovalent hydrocarbon group, and R ¹ and R ² described above are exemplified. When there are a plurality of siloxane units having ³ , R3 may be the same group or different groups ^, respectively). The content of _4/2 units of SiO is preferably 5 mol% or more, more preferably 10 mol to 95 mol%, and particularly preferably 20 to 60 mol% of the total siloxane unit in the organopolysiloxane resin of the component (B). Is.
Further, the organopolysiloxane preferably has a weight average molecular weight in the range of 500 to 100,000 from the viewpoint of isolation.

The synthesis of organopolysiloxanes having such a resin structure is easy by combining the compounds that are the source of each unit so that the production units are in the required ratio, and for example, performing (co) hydrolysis in the presence of an acid. Can be done.

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

Further, the addition-curable silicone resin composition of the present invention contains the component (A) in an amount of 0 parts by mass or more and less than 50 parts by mass, the component (B) in an amount of more than 50 parts by mass and 100 parts by mass or less, and the component (A) and ( B) Contains 100 parts by mass of the components in total. When the number of parts by mass of the components (A) and (B) is out of the above range, the tensile strength cannot be sufficiently maintained, and sufficient strength cannot be obtained when used for an optical element or the like.

<Ingredient (C)>
The component (C) is an organic silicon compound having two or more silicon atom-bonded hydrogen atoms (that is, SiH groups) in one molecule, preferably an organic silicon compound having no aliphatic unsaturated group (SiH group-containing organic silicon). Compound), which reacts with the components (A) and (B) in a hydrosilylation reaction and acts as a cross-linking agent. The component (C) may be used alone or in combination of two or more.

As the component (C), any known compound can be used as long as it is an organic silicon compound having two or more silicon atom-bonded hydrogen atoms in one molecule, and for example, organohydrogenpolysiloxane and organohydro can be used. Examples thereof include gensilanes, organic oligomers and organic polymers having at least two SiH groups per molecule, and among them, organohydrogenpolysiloxane having at least two SiH groups per molecule is preferable.

The organic group bonded to silicon in the component (C) preferably does not have an aliphatic unsaturated group, and is preferably an unsubstituted monovalent hydrocarbon group, or a halogen atom or an epoxy group-containing group (for example, an epoxy group, A monovalent hydrocarbon group substituted with a glycidyl group (glycidyl group, glycidoxy group), an alkoxy group (for example, a methoxy group, an ethoxy group, a propoxy group, a butoxy group) and the like can be exemplified. Examples of such a substituted or unsubstituted monovalent hydrocarbon group include an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 10 carbon atoms, more preferably a methyl group or an ethyl group, or groups thereof. Can be mentioned as a group substituted by the above-exemplified substituent. Further, when it has an epoxy group-containing group and / or an alkoxy group as a substituent of the monovalent hydrocarbon group, it is possible to impart adhesiveness to the cured product of the addition-curable silicone resin composition of the present invention. Further, when a halogen atom is used as a substituent of the monovalent hydrocarbon group, for example, a chlorine atom or a bromine atom may adversely affect the storage stability and curing of the addition-curable silicone resin composition of the present invention. do not have.

Further, the CF _3- (CF ₂ ) _q- (CH ₂ ) _r -group (q is 0 or more) similar to the CF _3- (CF ₂ ) _m- (CH ₂ ) _n- group in the above-mentioned component (A). It is more preferable to introduce a substituent defined by (an integer of 1 and r is an integer of 1 or more) into the component (C) from the viewpoint of further lowering the refractive index. Particularly preferable in terms of synthesis as the present invention are CF _3- (CH ₂ ) _2- , CF _3- (CF ₂ ) _3- (CH ₂ ) _2- , CF _3- (CF ₂ ) _5- (CH ₂ ). ₂ -group.

As long as the component (C) is an organic silicon compound having at least two SiH groups per molecule, the molecular structure of the organic silicon compound is not particularly limited, and is, for example, linear, cyclic, branched, or tertiary. Various organic silicon compounds conventionally produced, such as an original network structure (resin-like), can be used.

The number of the organic silicon compound as the component (C) is at least 2 (usually about 2 to 300), preferably 3 or more (more preferably 3 to 200, particularly preferably about 4 to 100) in one molecule. ) Has a SiH group. When the organic silicon compound of the component (C) has a linear structure or a branched chain structure, these SiH groups may be located only at either the end of the molecular chain or the non-terminal portion of the molecular chain. It may be located in both.

The number of silicon atoms (degree of polymerization) in one molecule of the organic silicon compound (C) is preferably 2 to 1,000, more preferably 3 to 200, and even more preferably 4 to 100. be. Further, the organic silicon compound of the component (C) is preferably liquid at 25 ° C., and the viscosity at 25 ° C. measured by a rotational viscometer is preferably 1 to 1,000 mPa · s, more preferably 10 to 100 mPa.・ It is about s.

As the organic silicon compound of the component (C), for example, a compound represented by the following average composition formula (2) can be used.

R ⁴ _{a'H b} SiO _{(4-a'-b) / 2} ... (2)

(In the formula, ^R4 is a silicon atom-bonded monovalent hydrocarbon group that is the same or different from each other and is substituted or unsubstituted other than the aliphatic unsaturated group, and a'and b are 0.7 ≦ a'. ≤2.1, 0.001≤b≤1.0 and 0.8≤a'+ b≤3.0, preferably 1.0≤a'≤2.0, 0.01≤b≤1.0 And, it is a positive number that satisfies 1.5 ≦ a'+ b ≦ 2.5.)

The silicon atom-bonded monovalent hydrocarbon group substituted or unsubstituted other than the aliphatic unsaturated group of ^R4 is specifically exemplified as an unsubstituted or substituted monovalent hydrocarbon group other than the above aliphatic unsaturated group. Examples thereof include a substituted or unsubstituted group such as an alkyl group having 1 to 6 carbon atoms or a haloalkyl group and an aryl group having 6 to 10 carbon atoms. ^R4 is preferably an alkyl group having 1 to 6 carbon atoms or a haloalkyl group.

Examples of the organohydrogensiloxane represented by the average composition formula (2) include a cyclic compound containing at least 4 organohydrogensiloxane units represented by the formula: R ⁴ HSiO, and a formula: R ⁴ ₃ SiO (HR ⁴ ). SiO) _c Compound represented by SiR ⁴ ₃ , formula: HR ⁴ ₂ SiO (HR ⁴ SiO) _d SiR ⁴ ₂ Compound represented by H, formula: HR ⁴ ₂ SiO (HR ⁴ SiO) _e (R ⁴ ₂ SiO) _f Examples thereof include compounds represented by _SiR ⁴² H. In the above formula, R ⁴ is as described above, and c to f are at least 1.

The organohydrogensiloxane represented by the average composition formula ( _{2) is a siloxane unit represented by the formula: H3 SiO 1/2 ,} a siloxane unit represented by the formula: ^R4 HSiO, and / or a formula: ^R4 . ₂ It may contain a siloxane unit represented by HSiO _1/2 . The organohydrogensiloxane may contain a monoorganosiloxane unit, a diorganosiloxane unit, a triorganosiloxane unit and / or a SiO _4/2 unit that do not contain a SiH group. ^R4 in the above formula is as described above.

When the component (C) is an organohydrogenpolysiloxane having at least two SiH groups per molecule, specific examples thereof include 1,1,3,3-tetramethyldisiloxane, 1,3,5. 7-Tetramethylcyclotetrasiloxane, Tris (hydrogendimethylsiloxy) methylsilane, Tris (hydrogendimethylsiloxy) phenylsilane, methylhydrogencyclopolysiloxane, methylhydrogensiloxane / dimethylsiloxane cyclic copolymer, both ends of molecular chain Trimethylsiloxy group-blocked methylhydrogenpolysiloxane, molecular chain double-ended trimethylsiloxy group-blocked dimethylsiloxane / methylhydrogensiloxane copolymer, molecular chain double-ended trimethylsiloxy group-blocked diphenylsiloxane / methylhydrogensiloxane copolymer, molecular chain Double-ended trimethylsiloxy group-blocked methylphenylsiloxane / methylhydrogensiloxane copolymer, molecular chain double-ended trimethylsiloxy group-blocked dimethylsiloxane / methylhydrogensiloxane / methylphenylsiloxane copolymer, molecular chain double-ended trimethylsiloxy group-blocked dimethyl Siloxane / methylhydrogensiloxane / diphenylsiloxane copolymer, dimethylhydrogensiloxy group-blocked methylhydrogenpolysiloxane at both ends of the molecular chain, dimethylhydrogensiloxy group-blocked dimethylpolysiloxane at both ends of the molecular chain, dimethylhydrogen at both ends of the molecular chain Syloxy group-blocked dimethylsiloxane / methylhydrogensiloxane copolymer, molecular chain double-ended dimethylhydrogensiloxy group-blocked dimethylsiloxane / methylphenylsiloxane copolymer, molecular chain double-ended dimethylhydrogensiloxy group-blocked dimethylsiloxane / diphenylsiloxane Polymer, dimethylhydrogensiloxy group-blocked methylphenylpolysiloxane at both ends of the molecular chain, dimethylhydrogensiloxy group-blocked diphenylpolysiloxane at both ends of the molecular chain, dimethylhydrogensiloxy group-blocked diphenylsiloxane / methylhydrogensiloxane at both ends of the molecular chain _Polymers , in each of these exemplary compounds, organohydrogenpolysiloxanes in which some or all of the methyl groups are substituted with other alkyl groups such as ethyl and propyl groups, represented by the formula: _R43 SiO ^1/2 . Siloxane unit and _formula : R ₄₂ HSiO ^1/2 Organosiloxane copolymer consisting of the siloxane unit shown and the siloxane unit represented by the formula: SiO _4/2 , the siloxane unit represented by the formula: R _{42 HSiO 1/2 and} the siloxane represented by the formula: _{SiO 4/2} ^. Organosiloxane copolymer consisting of units, siloxane unit represented by formula: R ⁴ HSiO _2/2 and siloxane unit represented by formula: R ⁴ SiO _3/2 and formula: siloxane represented by formula: H ₃ SiO _1/2 . Examples thereof include an organosiloxane copolymer consisting of either one or both of the units, and a mixture consisting of two or more of these organopolysiloxanes. R ⁴ in the above formula has the same meaning as described above.

As for the blending amount of the component (C), the molar ratio of the SiH group in the component (C) to the aliphatic unsaturated group in the components (A) and (B) is 0.2 ≦ SiH group / aliphatic unsaturated group ≦. The amount is 5.0, preferably 0.5 ≦ SiH group / aliphatic unsaturated group ≦ 2.0.

<(D) component>
The component (D) is a platinum group metal-based catalyst that promotes the hydrosilylation addition reaction between the components (A) and (B) and the component (C).

The platinum group metal-based catalyst of the component (D) promotes the hydrosilylation addition reaction between the silicon atom-bonded aliphatic unsaturated group in the components (A) and (B) and the SiH group in the component (C). If so, any catalyst may be used.

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

Examples of the component (D) include platinum group metals such as platinum, palladium, and rhodium, platinum chloride acid, alcohol-modified platinum chloride acid, a coordinate compound between platinum chloride acid and olefins, a vinylsiloxane or an acetylene compound, and tetrakis. Examples thereof include platinum group metal compounds such as (triphenylphosphine) palladium and chlorotris (triphenylphosphine) rhodium, and platinum compounds are particularly preferable.

The blending amount of the component (D) may be an effective amount as a hydrosilylation catalyst, preferably 0.1 in terms of the mass of the platinum group metal element with respect to the total mass of the components (A), (B) and (C). It is in the range of about 1000 ppm, more preferably in the range of 1 to 500 ppm.

≪Other optional ingredients≫
The addition-curable silicone resin composition of the present invention contains known antioxidants such as 2,6-di-t-butyl-4-methylphenol in order to suppress the occurrence of coloring, cloudiness, oxidative deterioration, etc. of the cured product. The agent may be blended. Further, in order to impart resistance to photodegradation, a light stabilizer such as a hindered amine-based stabilizer may be added. Further, if necessary, an inorganic filler such as fumed silica may be blended, or a dye, a pigment, a flame retardant or the like may be blended in order to improve the strength.

[Cursed product]
The addition-curable silicone resin composition of the present invention can be cured under known curing conditions by a known curing method. Specifically, the composition can be cured by heating at room temperature to 200 ° C., preferably 80 to 160 ° C. The heating time may be about 0.5 minutes to 5 hours, particularly about 1 minute to 3 hours, but when accuracy such as for LED encapsulation is required, it is preferable to lengthen the curing time. The form of the obtained cured product is not particularly limited, and may be, for example, any of a gel cured product, an elastomer cured product, and a resin cured product.

The cured product of the addition-curable silicone resin composition of the present invention preferably has a light transmittance of 80% or more at a wavelength of 300 to 800 nm at 25 ° C. in a layered state having a thickness of 2 mm. With such a thing, visible light at 25 ° C., particularly light transmittance at a wavelength of 400 nm can be made excellent, and light extraction efficiency can also be made excellent.

Further, in order to improve the originally desired performance of optical elements such as LEDs, particularly the light transmittance at a wavelength of 400 nm at 25 ° C., the refractive index (25 ° C.) of the cured product in visible light (589 nm) is 1.37 or less. Is preferable, and 1.35 to 1.37 is particularly preferable. With such a case, the visible light at 25 ° C., particularly the light transmittance at a wavelength of 400 nm can be more reliably improved, and the light extraction efficiency can also be improved.

Further, in the addition-curable silicone resin composition of the present invention, the amount of the optional component described above can be adjusted in order to satisfy the characteristics such as light transmission.

Further, the cured product of the addition-curable silicone resin composition of the present invention preferably has a tensile strength of 0.5 MPa or more. If it is such a thing, it will have particularly good rubber-like properties and strength properties.

Further, it is preferable that the addition-curable silicone resin composition of the present invention is for encapsulating an optical element. In such a case, since the cured product of the addition-curable silicone resin composition is colorless and transparent and has a low refractive index, it can be particularly preferably used for encapsulating an optical element.

[Optical element]
Further, the cured product of the addition-curable silicone resin composition of the present invention is excellent in heat resistance, cold resistance, and electrical insulation like the cured product of a normal addition-curable silicone composition. Examples of the optical element sealed by the encapsulant made of the addition curable silicone resin composition of the present invention include LEDs, semiconductor lasers, photodiodes, phototransistors, solar cells, CCDs and the like. Such an optical element can be sealed by applying the addition-curable silicone resin composition of the present invention and curing the applied composition by a known curing method.

FIG. 1 is a schematic cross-sectional view showing an example (light emitting semiconductor device) of the optical element of the present invention. In the light emitting semiconductor device (optical semiconductor device) 10 shown in FIG. 1, the light emitting element (optical semiconductor element) 2 is fixed to a housing 1 having lead electrodes 3 and 4 by using a die bond material 5. The light emitting element 2 and the lead electrodes 3 and 4 are connected by a gold wire 6 and are sealed with a sealing resin 7 cured by using the addition-curing silicone resin composition of the present invention for sealing an optical element. ..

Such an optical element has good rubber-like properties and strength characteristics, has a lower refractive index in visible light than before, and has excellent product reliability with high transparency, low refractive index, and high intensity. Since the addition-curable silicone resin composition that can give a cured product is used, the reliability is excellent.

Hereinafter, the present invention will be specifically described with reference to Synthetic Examples, Examples and Comparative Examples, but the present invention is not limited thereto.
The characteristics of the organopolysiloxane composition and its cured product were measured as follows.
The viscosities in Examples and Comparative Examples are values measured at 25 ° C. using a rotational viscometer. The refractive index is a value (nD25) measured at 25 ° C. with a refractive index of 589 nm using a digital refractometer RX-5000 manufactured by ATAGO.

[Hardness and tensile strength of cured product]
A cured product was prepared by heating the composition in a hot air circulation oven at 150 ° C. for 2 hours. After that, it was measured according to JIS-K6289.

[Light transmittance of cured product]
The transmittance of a cured product having a thickness of 2 mm and having a wavelength of 400 nm, which was prepared by heating the composition in a hot air circulation oven at 150 ° C. for 2 hours, was measured at 25 ° C. by a spectrophotometer.

[Optical semiconductor package]
As an optical semiconductor element, an LED chip having a light emitting layer made of InGaN and having a main light emitting peak of 450 nm is used in the SMD3020 package and the SMD5050 package (I-CHIUN PRECISION INDUSTRY CO., Co., Ltd., the resin part is PPA (polyphthalamide)). ), And wire-bonded, a light-emitting semiconductor device (optical semiconductor device) 10 having a structure as shown in FIG. 1 was used as an optical semiconductor package. Here, in FIG. 1, as described above, 1 is a housing, 2 is a light emitting element (optical semiconductor element), 3 and 4 are lead electrodes, 5 is a die bond material, 6 is a gold wire, and 7 is a sealing resin. The curing conditions of the sealing resin 7 are 150 ° C. and 2 hours.

[Crack resistance]
Five light emitting semiconductor devices were manufactured, and the five manufactured light emitting semiconductor devices were repeatedly set to temperature conditions of −45 ° C. and 125 ° C. (15 minutes each), and the number of LEDs in which cracks occurred after 100 cycles did not crack at all. In the case of ○, if even one crack occurred, it was evaluated as × (PKG test). That is, when it is ◯, it means that the crack resistance is excellent and the reliability is excellent.

Hereinafter, synthesis examples, examples, and comparative examples will be described, but in the following examples, the symbols in the composition formula indicate the following units.

M : (CH ₃ ) ₃ SiO _1/2
^MH : H (CH ₃ ) ₂ SiO _1/2
M ^vi : (CH ₂ = CH) (CH ₃ ) ₂ SiO _1/2
D : (CH ₃ ) ₂ SiO _2/2
DH: ^H (CH ₃ ) SiO _2/2
D ^Vi : (CH ₂ = CH) (CH ₃ ) SiO _2/2
^DF1 : (CF ₃ -CH ₂ -CH ₂ ) (CH ₃ ) SiO _2/2
^DF2 : [CF _3- (CF ₂ ) ₃ -CH ₂ -CH ₂ ] (CH ₃ ) SiO _2/2
^DF3 : [CF _3- (CF ₂ ) ₅ -CH ₂ -CH ₂ ] (CH ₃ ) SiO _2/2
T : CH ₃ SiO _3/2
T ^F1 : (CF ₃ -CH ₂ -CH ₂ ) SiO _3/2
T ^F3 : [CF _3- (CF ₂ ) ₅ -CH ₂ -CH ₂ ] SiO _3/2
Q : SiO _4/2

[Synthesis Example 1]
In a 2000 ml four-necked flask equipped with a stirrer, cooling tube, dropping funnel, and thermometer, (3,3,4,4,5,5,6,6,7,7,8,8,8- Tridecafluorooctyl) trimethoxysilane 280.8 g, methylpolysilicate 117.5 g, hexamethyldisiloxane 32.4 g, 1,3-divinyltetramethyldisiloxane 19.5 g, isopropyl alcohol 24.0 g and methanesulfonic acid 5 .7 g was added and stirred and mixed. 51.6 g of water was added dropwise thereto, 1050 g of hexafluoromethoxylene was added thereto, and then a hydrolysis reaction was carried out at 70 ° C. for 5 hours. 9.3 g of a 50% potassium hydroxide aqueous solution was added thereto, the temperature was raised to distill off the low boiling point component, and a condensation reaction was carried out at 120 ° C. for 5 hours. 3.0 g of methanesulfonic acid was added as a neutralizing agent, and the neutralization treatment was carried out at 120 ° C. for 2 hours. After cooling, it was filtered to obtain organopolysiloxane. As a result of analyzing the reaction product by NMR, GPC, etc., this resin had an average composition _formula of ^M4 M ^Vi _2.1 Q ₁₀ T _F36 .

[Synthesis Example 2]
In a 2000 ml four-necked flask equipped with a stirrer, cooling tube, dropping funnel, and thermometer, (3,3,4,4,5,5,6,6,7,7,8,8,8- Tridecafluorooctyl) trimethoxysilane 280.8 g, methylpolysilicate 152.8 g, hexamethyldisiloxane 32.4 g, 1,3-divinyltetramethyldisiloxane 27.9 g, isopropyl alcohol 49.4 g and methanesulfonic acid 6 .3 g was added and stirred and mixed. 60.6 g of water was added dropwise thereto, 1152 g of hexafluoromethoxylene was added thereto, and then a hydrolysis reaction was carried out at 70 ° C. for 5 hours. 10.2 g of a 50% potassium hydroxide aqueous solution was added thereto, the temperature was raised to distill off the low boiling point component, and a condensation reaction was carried out at 120 ° C. for 5 hours. 3.3 g of methanesulfonic acid was added as a neutralizing agent, and the neutralization treatment was carried out at 120 ° C. for 2 hours. After cooling, it was filtered to obtain organopolysiloxane. As a result of analyzing the reaction product by NMR, GPC, etc., this resin had an average composition formula of M ₄ M ^Vi ₃ Q ₁₃ T ^F ₃₆ .

[Synthesis Example 3]
1183 g of methanol, 930 g of vinyltrimethoxysilane, 200 g of methylvinyldimethoxysilane, (3,3,4,4,5,5,6,6,7,7,8,8,8-tri) in a 10 L flask. 2192 g of decafluorooctyl) trichlorosilane and 59 g of methanesulfonic acid were added, and the mixture was stirred and mixed. Therefore, 429 g of water was added dropwise, 4551 g of hexafluoromethoxylene was added, and then a hydrolysis reaction was carried out at 70 ° C. for 5 hours. Therefore, 0.76 g of a 50% potassium hydroxide aqueous solution was added, the temperature was raised to distill off the low boiling point component, and a condensation reaction was carried out at 120 ° C. for 5 hours. A neutralization reaction was carried out by adding 1.67 g of methyltrichlorosilane and 7.3 g of potassium acetate as neutralizing agents and stirring at room temperature for 12 hours. As a result of analyzing the reaction product by NMR, GPC, etc., this resin had an average composition formula of D ^Vi _1.7 T ^F3 _5.0 T _7.5 .

[Synthesis Example 4]
152.6 g of 3,3,3-trifluoropropyl-trimethoxysilane, 35.3 g of tetramethoxysilane, hexamethyldisiloxane in a 1 L four-necked flask equipped with a stirrer, cooling tube, dropping funnel and thermometer. 10.5 g, 20.9 g of 1,3-divinyltetramethyldisiloxane, 32 g of isopropyl alcohol and 2.8 g of methanesulfonic acid were added and mixed by stirring. 34.8 g of water was added dropwise thereto, 220 g of hexafluoromethoxylene was added, and then a hydrolysis reaction was carried out at 70 ° C. for 5 hours. 4.6 g of a 50% potassium hydroxide aqueous solution was added thereto, the temperature was raised to distill off low boiling point components, and a condensation reaction was carried out at 120 ° C. for 5 hours. 1.5 g of methanesulfonic acid was added as a neutralizing agent, and the neutralization treatment was carried out at 120 ° C. for 2 hours. After cooling, the resin was obtained by filtration. As a result of analyzing the reaction product by NMR, GPC, etc., this resin had an average composition formula of M _1.8 M ^Vi _3.2 Q _4.3 T ^F1 _10.0 .

[Example 1]
100 parts by mass of the reaction product 1 obtained in Synthesis Example ₁ as a component (B), and 29.0 parts by mass of an organohydrogenpolysiloxane represented by ^MH ₂ D ^F3 ₂ D ^F16 as a component (C). In addition, 0.1 part by mass of 1-ethynylcyclohexanol was uniformly mixed (note that the molar ratio of SiH carbon-carbon double bond in the above composition is 1.0). Further, as the component (D), a composition was obtained by mixing with 1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex of platinum (the amount of the above complex added was determined in the composition. The amount of platinum metal in the complex is 6 ppm in terms of mass.).

[Example 2]
40 parts by mass of an organopolysiloxane having a viscosity of 200 mPa · s represented by M ^Vi ₂ D ^F2 ₄ D ^F1 ₁₂ as a component (A), and 60 parts by mass of the reaction product 1 obtained in Synthesis Example 1 as a component (B). , (C) 29.2 parts by mass of organohydrogenpolysiloxane represented by ^MH ₂ D ^F3 ₂ D ^F16 and 0.1 part by mass of ₁ -ethynylcyclohexanol were uniformly mixed (note that the above). The molar ratio of SiH carbon-carbon double bonds in the composition is 1.0). Further, as the component (D), a composition was obtained by mixing with 1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex of platinum (the amount of the above complex added was determined in the composition. The amount of platinum metal in the complex is 6 ppm in terms of mass.).

[Example 3]
100 parts by mass of the reaction product 1 obtained in Synthesis Example ₂ as a component (B), and 38.7 parts by mass of an organohydrogenpolysiloxane represented by ^MH ₂ D ^F3 ₂ D ^F16 as a component (C). In addition, 0.1 part by mass of 1-ethynylcyclohexanol was uniformly mixed (note that the molar ratio of SiH carbon-carbon double bond in the above composition is 1.0). Further, as the component (D), a composition was obtained by mixing with 1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex of platinum (the amount of the above complex added was determined in the composition. The amount of platinum metal in the complex is 6 ppm in terms of mass.).

[Example 4]
45 parts by mass of organopolysiloxane having a viscosity of 200 mPa · s represented by M ^Vi ₂ D ^F2 ₄ D ^F1 ₁₂ as a component (A), and 55 parts by mass of the reaction product 1 obtained in Synthesis Example 1 as a component (B). , (C) 29.2 parts by mass of organohydrogenpolysiloxane represented by ^MH ₂ D ^F3 ₂ D ^F16 and 0.1 part by mass of ₁ -ethynylcyclohexanol were uniformly mixed (note that the above). The molar ratio of SiH carbon-carbon double bonds in the composition is 1.0). Further, as the component (D), a composition was obtained by mixing with 1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex of platinum (the amount of the above complex added was determined in the composition. The amount of platinum metal in the complex is 6 ppm in terms of mass.).

[Comparative Example 1]
77.1 parts by mass of the reaction product obtained in Synthesis Example 3, 11 parts by mass of the organohydrogenpolysiloxane represented by ^MH ₂ D ^F3 ₂ D ^F1 ₆ and 5.4 parts by mass of ^MH ₃ T ^F3 ₆ . , And 0.1 part by mass of 1-ethynylcyclohexanol were uniformly mixed (note that the molar ratio of SiH carbon-carbon double bond in the above composition is 1.0). Further, it was mixed with 1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex of platinum to obtain a composition (the amount of the complex added was the platinum in the complex in the composition. The amount of metal to be 15 ppm by mass.).

[Comparative Example 2]
50 parts by mass of an organopolysiloxane having a viscosity of 2000 mPa · s represented by M ^Vi ₂ D ^F1 ₂₇ , 50 parts by mass of the reaction product obtained in Synthesis Example 4, and an organo represented by M ₂ ^DH ₁₄ D ^F1 ₁₄ . 18.9 parts by mass of hydrogen polysiloxane and 0.1 part by mass of 1-ethynylcyclohexanol were uniformly mixed (note that the molar ratio of SiH carbon-carbon double bond in the above composition is 1.0. .). Further, it was mixed with 1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex of platinum to obtain a composition (the amount of the complex added was the platinum in the complex in the composition. The amount of metal to be 6 ppm by mass.).

[Comparative Example 3]
70 parts by mass of organopolysiloxane having a viscosity of 200 mPa · s represented by M ^Vi ₂ D ^F2 ₄ D ^F1 ₁₂ , 30 parts by mass of the reaction product 1 obtained in Synthesis Example 1, ^MH ₂ D ^F3 ₂ D ^F1 ₆ 29.3 parts by mass of organohydrogenpolysiloxane represented by 1 and 0.1 part by mass of 1-ethynylcyclohexanol were uniformly mixed (note that the molar ratio of SiH carbon-carbon double bond in the above composition is It is 1.0.). Further, it was mixed with 1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex of platinum to obtain a composition (the amount of the complex added was the platinum in the complex in the composition. The amount of metal to be 6 ppm by mass.).

[Comparative Example 4]
50 parts by mass of organopolysiloxane with a viscosity of 5000 mPa · s represented by M ^Vi ₂ D ₄₃₆ , 50 parts by mass of silicone resin represented by M ^Vi _1.2 M _{7.4 Q10} , represented by M ₂ ^DH ₈ . 4.5 parts by mass of organohydrogenpolysiloxane and 0.1 part by mass of 1-ethynylcyclohexanol were uniformly mixed (note that the molar ratio of SiH carbon-carbon double bond in the above composition is 1.5). It is.). Further, it was mixed with 1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex of platinum to obtain a composition (the amount of the complex added was the platinum in the complex in the composition. The amount of metal to be 15 ppm by mass.).

[Comparative Example 5]
50 parts by mass of organopolysiloxane having a viscosity of 200 mPa · s represented by M ^Vi ₂ D ^F2 ₄ D ^F1 ₁₂ , 50 parts by mass of the reaction product 1 obtained in Synthesis Example 1, ^MH ₂ D ^F3 ₂ D ^F1 ₆ 29.2 parts by mass of organohydrogenpolysiloxane represented by 1 and 0.1 part by mass of 1-ethynylcyclohexanol were uniformly mixed (note that the molar ratio of SiH carbon-carbon double bond in the above composition is It is 1.0.). Further, it was mixed with 1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex of platinum to obtain a composition (the amount of the complex added was the platinum in the complex in the composition. The amount of metal to be 6 ppm by mass.).

As shown in Table 1, Examples 1, 2, 3 and 4 in which the addition-curable silicone resin composition of the present invention was used as a sealing material had a low refractive index of 1.37 or less, and had transparency and light transmission. It was excellent in properties, especially in tensile strength.
On the other hand, Comparative Example 1 was a resin having no siloxane unit represented by SiO _4/2 , and its tensile strength was inferior to that of Examples, and its reliability (crack resistance) in the PKG test was inferior. In Comparative Example 2, the long-chain fluoroalkyl group was not contained, and the refractive index value could not be satisfied. In Comparative Examples 3 and 5, a resin having a siloxane unit represented by SiO _4/2 is used, but the tensile strength is inferior to that of the examples due to the small amount of the resin, and cracks occur. It can be seen that the reliability is inferior. Comparative Example 4 is a dimethyl organopolysiloxane, which has a siloxane unit represented by SiO _4/2 , has high hardness and tensile strength, and is excellent in crack resistance, but has a high refractive index and a higher light transmittance than the examples. Was also inferior.

From the above, the addition-curable silicone resin composition of the present invention provides a cured product having a low refractive index, excellent transparency and light transmission, good hardness and tensile strength, and excellent reliability. It has been clarified that an addition-curable silicone resin composition that can be given and is suitable for optical applications can be provided.

The present invention is not limited to the above embodiment. The above embodiment is an example, and any one having substantially the same configuration as the technical idea described in the claims of the present invention and having the same effect and effect is the present invention. It is included in the technical scope of the invention.

1 ... Housing, 2 ... Light emitting element (optical semiconductor element), 3, 4 ... Lead electrode.
5 ... Die bond material, 6 ... Gold wire, 7 ... Sealing resin,
10 ... Light emitting semiconductor device (optical semiconductor device).

Claims (7)

(A) A linear chain having two or more silicon atom-bonded aliphatic unsaturated groups and one or more silicon atom-bonded CF _3- (CF ₂ ) _m- (CH ₂ ) _n- group in one molecule. A certain organopolysiloxane (where m is an integer of 0 or more and n is an integer of 1 or more) 0 parts by mass or more and less than 50 parts by mass,
(B) One molecule has two or more silicon atom-bonded aliphatic unsaturated groups and one or more silicon atom-bonded CF _3- (CF ₂ ) _o- (CH ₂ ) _p -group, and SiO Organopolysiloxane having a siloxane unit represented by _4/2 (where o is an integer of 5 or more and p is an integer of 1 or more) more than 50 parts by mass and less than 100 parts by mass,
(However, the total of the component (A) and the component (B) is 100 parts by mass.)
(C) An organic silicon compound having two or more silicon atom-bonded hydrogen atoms in one molecule: the molar ratio of the total aliphatic unsaturated group of the components (A) and (B) to the SiH group of the component (C). However, 0.2 ≤ SiH group / aliphatic unsaturated group ≤ 5.0,
(D) Platinum group metal catalyst: effective amount,
An addition-curable silicone resin composition, which comprises. The component (C) further has one or more silicon atom-bonded CF _3- (CF ₂ ) _q- (CH ₂ ) _r -groups in one molecule (where q is an integer of 0 or more and r is 1). The addition-curable silicone resin composition according to claim 1, wherein the integer is the above. The addition-curable silicone resin composition is characterized in that it is cured to give a cured product having a refractive index (25 ° C.) of visible light (589 nm) of 1.37 or less. The addition-curable silicone resin composition according to. The addition-curable silicone resin composition is characterized in that it is cured to give a cured product having a light transmittance at a wavelength of 300 to 800 nm at 25 ° C. of 80% or more in a layered state having a thickness of 2 mm. The addition-curable silicone resin composition according to any one of items 1 to 3. The addition-curable silicone resin according to any one of claims 1 to 4, wherein the addition-curable silicone resin composition has a tensile strength of 0.5 MPa or more after curing . Composition. The addition-curable silicone resin composition according to any one of claims 1 to 5, wherein the addition -curable silicone resin composition is for encapsulating an optical element. An optical element sealed with a cured product of the addition-curable silicone resin composition according to any one of claims 1 to 6.

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