JP5621819B2 - Curable composition, cured product, and optical semiconductor device - Google Patents

Description

  The present invention relates to a curable composition, a cured product, and an optical semiconductor device.

  Addition-curable silicone rubber compositions are used in various applications such as LED package sealants because they form cured products having excellent rubber properties such as weather resistance, heat resistance, hardness, and elongation. However, there is a problem that dust adheres because of the tack on the surface of the cured product, and the parts feeder that is used for selecting products sticks to each other.

In order to eliminate the tack, a hard silicone resin may be used. However, the cured product has a low impact resistance, and there is a problem that a crack is easily generated particularly by a thermal shock.
Therefore, by utilizing both characteristics, a method for improving the strength of the cured product by adding a resinous organopolysiloxane to the addition-curable silicone rubber composition, and curing of the addition-curable silicone rubber composition A method of coating a resin on an object has been proposed (Patent Documents 1 and 2).

JP 2007-99835 A JP 2007-103494 A

  An object of the present invention is to provide a curable composition capable of obtaining a cured product with reduced tack, a cured product obtained from the curable composition, and an optical semiconductor device having the cured product.

The present invention for achieving the above object is as follows.
[1] A curable composition containing a polysiloxane (A) having an alkenyl group, a saturated hydrocarbon compound (B), and a polysiloxane (D) having at least two silicon-bonded hydrogen atoms per molecule.
[2] The curable composition according to the above [1], wherein the saturated hydrocarbon compound (B) has a boiling point of 50 ° C to 150 ° C under 1 atm.
[3] The curable composition according to [1] or [2], wherein the content ratio of the saturated hydrocarbon compound (B) is 0.1 to 5000 ppm.
[4] The curable composition according to any one of [1] to [3], wherein the saturated hydrocarbon compound (B) is a saturated alicyclic hydrocarbon compound.

[5] The curable composition according to any one of [1] to [4], wherein the polysiloxane (A) having an alkenyl group is a polysiloxane having an aryl group.
[6] Method for producing curable composition containing polysiloxane (A) having alkenyl group, saturated hydrocarbon compound (B) and polysiloxane (D) having at least two silicon-bonded hydrogen atoms per molecule Wherein at least one of the polysiloxane (A) and the polysiloxane (D) is synthesized using the saturated hydrocarbon compound (B) as a synthesis solvent, and the resulting polysiloxane-containing synthesis solution is concentrated. The manufacturing method of the curable composition characterized by using a thing.
[7] A cured product obtained by curing the curable composition according to any one of [1] to [5].
[8] An optical semiconductor device having a semiconductor light-emitting element and the cured product according to [7], which covers the semiconductor light-emitting element.

  The curable composition of the present invention can form a cured product with sufficiently reduced tack. An optical semiconductor device having a cured product formed from the curable composition of the present invention as a sealing material or the like is less likely to have dust or the like attached to the surface of the cured product, and is a parts feeder used for product selection. There is little risk of problems such as package sticking.

FIG. 1 is a schematic diagram showing a specific example of an optical semiconductor device.

<Curable composition>
The curable composition of the present invention contains a polysiloxane (A) having an alkenyl group, a saturated hydrocarbon compound (B), and a polysiloxane (D) having at least two silicon-bonded hydrogen atoms per molecule. In addition, the curable composition of the present invention can contain a hydrosilylation catalyst (C) and an additive.
In the present invention, “polysiloxane” means a compound having a molecular skeleton in which two or more siloxane units (Si—O) are bonded.

Polysiloxane (A)
The polysiloxane (A) is a polysiloxane having an alkenyl group. The polysiloxane (A) is a main component of the present composition, and is cured by a hydrosilylation reaction with the polysiloxane (D) to become a main body of the cured product.

The polysiloxane (A) is not particularly limited as long as it can be cured by a hydrosilylation reaction with the polysiloxane (D).
The polysiloxane (A) may be the same compound as the polysiloxane (D). That is, polysiloxane (A) and polysiloxane (D) may be polysiloxane having an alkenyl group and at least two silicon-bonded hydrogen atoms in the same molecule. Such a polysiloxane functions as a crosslinking agent as well as the main component of the present composition.

  Examples of the alkenyl group that the polysiloxane (A) has include a vinyl group, an allyl group, a propenyl group, an isopropenyl group, a butenyl group, an isobutenyl group, a pentenyl group, a heptenyl group, a hexenyl group, and a cyclohexenyl group. Among these, a vinyl group, an allyl group, and a hexenyl group are preferable.

  The alkenyl group content in the polysiloxane (A) is preferably 3 to 50 mol%, more preferably 5 when the number of all Si atoms contained in the polysiloxane (A) is 100 mol%. It is -40 mol%, More preferably, it is 10-30 mol%. When the content of the alkenyl group is within the above range, the hydrosilylation reaction between the polysiloxane (A) and the polysiloxane (D) proceeds suitably, and a cured product having high strength can be obtained.

The polysiloxane (A) is preferably a polysiloxane having an aryl group.
When the polysiloxane (A) has an aryl group, a characteristic that high luminance is obtained when used as an LED sealing material is exhibited. When the number of all Si atoms contained in the polysiloxane (A) is 100 mol%, the content of aryl groups contained in the polysiloxane (A) is preferably 30 to 120 mol%, more preferably It is 50-110 mol%, More preferably, it is 70-100 mol%. When the aryl group content is in the range of 30 to 120 mol%, a cured film having high luminance and high refractive index can be obtained from the present composition. Examples of the aryl group include a phenyl group, a tolyl group, a xylyl group, and a naphthyl group.

  The polysiloxane (A) is preferably a polysiloxane represented by the following formula (1). When the polysiloxane (A) has a siloxane unit in which two aryl groups are bonded to the same silicon atom constituting the polysiloxane chain as described above, the moisture resistance of the cured product obtained from the curable composition of the present application is as follows. Increases nature.

（式中、Ｒ¹、Ｒ²およびＲ³は、それぞれ独立に、アルキル基、アルケニル基、アリール基またはグリシドキシアルキル基を示す。Ｒ^Ar1はアリール基を示す。Ｘは水素原子または炭素数１〜３のアルキル基を示す。ａ、ｃ、ｅおよびｆはそれぞれ独立に０以上の整数を示す。ｂおよびｄはそれぞれ独立に１以上の整数を示す。）

(In the formula, R ¹ , R ² and R ³ each independently represents an alkyl group, an alkenyl group, an aryl group or a glycidoxyalkyl group. R ^Ar1 represents an aryl group. X represents a hydrogen atom or a carbon number. 1 to 3 alkyl groups, a, c, e and f each independently represents an integer of 0 or more, and b and d each independently represents an integer of 1 or more.

In formula (1), R ¹ , R ² and R ³ each independently represents an alkyl group, an alkenyl group, an aryl group or a glycidoxyalkyl group. That is, for one siloxane unit (structural unit) to which the symbol a is attached, three R ^{1 s} independently represent an alkyl group, an alkenyl group, an aryl group, Or glycidoxyalkyl. If for example, three more than one R ¹ is an alkyl group of R ^1, the alkyl group may be the same alkyl group or may be different alkyl groups. When the code | symbol a is an integer greater than or equal to 2, each siloxane unit to which the code | symbol a was attached | subjected may be the same or different. R ² and R ³ are the same as R ¹ .

Provided that at least two alkenyl of R ^1, R ³ present in the siloxane units R ² and sign d is attached is present in the siloxane units code c is attached to exist in the siloxane units sign a is attached And at least two alkenyl groups are present in one molecule of the polysiloxane (A) represented by the above formula (1). For example, one of the three R ¹ groups present in one siloxane unit with the symbol a may be an alkenyl group, and two or more siloxane units may be present. Two or more of the three R ¹ present in one siloxane unit to which the symbol a is attached are alkenyl groups, and one or more siloxane units may be present. One of the three R ¹ groups present in one siloxane unit with the symbol a is an alkenyl group, one siloxane unit is present, and one siloxane unit with the symbol c is present. One of the two R ² groups may be an alkenyl group, and one or more siloxane units may be present.

In addition, regarding the siloxane unit with the symbol c, when one R ² is an aryl group among the two R ² bonded to the same silicon atom, the other R ² is not an aryl group.

  Examples of the alkyl group include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, bornyl group, norbornyl group. And an adamantyl group. Among these, a methyl group is preferable.

  Examples of the alkenyl group include vinyl group, allyl group, propenyl group, isopropenyl group, butenyl group, isobutenyl group, pentenyl group, heptenyl group, hexenyl group, and cyclohexenyl group. Among these, a vinyl group, an allyl group, and a hexenyl group are preferable.

Examples of the aryl group include a phenyl group, a tolyl group, a xylyl group, and a naphthyl group. Among these, a phenyl group is preferable.
Examples of the glycidoxyalkyl group include glycidoxypropyl.

In formula (1), R ^Ar1 represents an aryl group. The aryl group represented by R ^Ar1 is the same as the aryl group represented by R ¹ , R ² and R ³ .
In formula (1), X represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

In formula (1), a, c, e and f each independently represent an integer of 0 or more. b and d each independently represent an integer of 1 or more.
The present curable composition comprises the polysiloxane (A) having a siloxane unit having a symbol b, that is, a siloxane unit in which two aryl groups are bonded to the same silicon atom constituting the polysiloxane chain. The moisture resistance of the cured product obtained from is improved.

  When the total of a, b, c, d, e and f is 100%, the ratio of a is preferably 0 to 70%, more preferably 0 to 40%. The proportion of b is preferably 1 to 70%, more preferably 1 to 40%. The proportion of c is preferably 0 to 70%, more preferably 0 to 40%. The proportion of d is preferably 1 to 80%, more preferably 30 to 70%. The proportion of e is preferably 0 to 50%, more preferably 0 to 20%. The proportion of f is preferably 0 to 40%, more preferably 0 to 10%.

  Polysiloxane (A) preferably has a polystyrene-equivalent weight average molecular weight measured by gel permeation chromatography in the range of 100 to 50000, and more preferably in the range of 500 to 5000. When the weight average molecular weight of the polysiloxane (A) is within the above range, it is easy to handle when producing a sealing material using the composition, and the cured product obtained from the composition is used as an optical semiconductor sealing material. It has sufficient strength.

  As a method for producing the polysiloxane (A), JP-A-6-9659, JP-A-2003-183582, JP-A-2007-008996, JP-A-2007-106798, JP-A-2007-169427 are disclosed. And a known method described in JP 2010-059359 A, for example, a method of co-hydrolyzing chlorosilane or alkoxysilane as each unit source in an appropriate synthesis solvent, or a co-hydrolyzate as an alkali metal catalyst. For example, a method of equilibrating reaction may be mentioned. When the polysiloxane (A) is synthesized using the saturated hydrocarbon compound (B) as the synthesis solvent, the resulting polysiloxane (A) -containing synthesis solution contains the saturated hydrocarbon compound (B). If a curable composition is prepared using a concentrate, operation which adds a saturated hydrocarbon compound (B) can be skipped.

Saturated hydrocarbon compound (B)
The curable composition of the present invention can form a cured product with sufficiently reduced tack by containing the saturated hydrocarbon compound (B) together with the polysiloxane (A) and the polysiloxane (D).

  Saturated hydrocarbon compounds (B) include saturated aliphatic hydrocarbon compounds such as n-pentane (36 ° C.), n-hexane (69 ° C.), n-heptane (98 ° C.), n-octane (126 ° C.), etc. Saturated alicyclic hydrocarbons such as methylcyclohexane (101 ° C), cyclohexane (81 ° C), ethylcyclohexane (130 ° C), dimethylcyclohexane (124 ° C), cycloheptane (118 ° C), cyclooctane (149 ° C), etc. Compound (in the parentheses indicate the boiling point at 1 atm). Among these, a saturated alicyclic hydrocarbon compound is preferable because the tack of the cured product can be more effectively reduced.

  The boiling point of the saturated hydrocarbon compound (B) is preferably 50 ° C. to 150 ° C. at 1 atmosphere, more preferably 70 to 140 ° C., and further preferably 80 to 130 ° C. When the boiling point of the saturated hydrocarbon compound (B) is 50 ° C. to 150 ° C. under 1 atm, tack of the cured product can be further reduced.

  In the curable composition of the present invention, the content of the saturated hydrocarbon compound (B) is preferably 0.1 to 5000 ppm, more preferably 0.1 to 1000 ppm, and still more preferably 0.1 to 100 ppm. is there. When the content ratio of the saturated hydrocarbon compound (B) is within the above range, the tack of the cured product can be more effectively reduced.

Polysiloxane (D)
The polysiloxane (D) is a polysiloxane having at least two silicon-bonded hydrogen atoms per molecule. That is, the polysiloxane (D) has at least two Si—H groups (hydrosilyl groups) per molecule. Polysiloxane (D) is a crosslinking agent for polysiloxane (A), and forms a cured product by a hydrosilylation reaction with polysiloxane (A).

  The polysiloxane (D) may be any polysiloxane having at least two silicon-bonded hydrogen atoms per molecule, which is used as a crosslinking agent in conventional hydrosilyl polysiloxane compositions.

As described above, the polysiloxane (D) may be the same compound as the polysiloxane (A).
Specific examples of the polysiloxane (D) include organohydrogenpolysiloxanes described in Patent Documents 1 and 2 .

  Polysiloxane (D) can be prepared by, for example, combining an alkoxysilane such as phenyltrimethoxysilane or diphenyldimethoxysilane with a hydrogensiloxane such as 1,1,3,3-tetramethyldisiloxane by a known method. It can be obtained by reacting in. When the polysiloxane (D) is synthesized using the saturated hydrocarbon compound (B) as a synthesis solvent, the resulting polysiloxane (D) -containing synthesis solution contains the saturated hydrocarbon compound (B). If a curable composition is prepared using a concentrate, operation which adds a saturated hydrocarbon compound (B) can be skipped.

  As content of polysiloxane (D) in the curable composition of this invention, the molar ratio of the silicon atom bond hydrogen atom amount in polysiloxane (D) with respect to the amount of alkenyl groups in polysiloxane (A) is 0.1-. 5 is preferable, more preferably 0.5 to 2, and still more preferably 0.7 to 1.4. When the content of the polysiloxane (D) is within the above range, the curing of the composition proceeds sufficiently, and the obtained cured product has sufficient heat resistance.

Catalyst for hydrosilylation reaction (C)
The hydrosilylation catalyst (C) is a catalyst for promoting the hydrosilylation reaction.
The hydrosilylation reaction catalyst (C) can be used without any particular limitation as long as it is a catalyst used as a hydrosilylation reaction catalyst in a conventional hydrosilyl polysiloxane composition.

Specific examples of the hydrosilylation catalyst (C) include a platinum-based catalyst, a rhodium-based catalyst, and a palladium-based catalyst. Among these, a platinum-based catalyst is preferable from the viewpoint of promoting the curing of the present composition. Examples of platinum-based catalysts include platinum-alkenylsiloxane complexes. Examples of the alkenylsiloxane include 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane. Etc. In particular, from the viewpoint of stability of the complex, 1,3-divinyl-1,1,3,3-tetra- disiloxane is preferable.

  The hydrosilylation reaction catalyst (C) in the curable composition of the present invention is an amount in which the hydrosilylation reaction of the polysiloxane (A) and the polysiloxane (D) actually proceeds, for example, 0.00% in the curable composition. 01 ppm to 10000 ppm is used.

Additives As long as the object of the present invention is achieved, the curable composition of the present invention contains, as necessary, inorganic fillers such as fine-particle silica such as fumed silica and quartz powder, titanium oxide, and zinc oxide. , Reaction retarders such as ethynylcyclohexanol, cyclo-tetramethyltetravinyltetrasiloxane, diluents such as diphenylbis (dimethylvinylsiloxy) silane, phenyltris (dimethylvinylsiloxy) silane, diphenylbis (dimethylhydroxysiloxy) silane, Additives such as pigments, flame retardants, heat-resistant agents, and antioxidants can be contained.

Production method of composition The curable composition of the present invention comprises the above-mentioned components, that is, polysiloxane (A), saturated hydrocarbon compound (B), polysiloxane (D), and hydrosilylation reaction catalyst (C) as necessary. ) And additives by a known method such as a mixer.

  Also, polysiloxanes such as polysiloxane (A) and polysiloxane (D) are synthesized using the saturated hydrocarbon compound (B) as a synthesis solvent, and the resulting polysiloxane-containing synthetic solution concentrate is hydrosilylated. It can also be produced by mixing with other components such as the reaction catalyst (C).

  As a viscosity in 25 degreeC of the curable composition of this invention, Preferably it is 1-1000000 mPa * s, More preferably, it is 10-10000 mPa * s. When the viscosity is within this range, the operability of the composition is improved.

  The curable composition of the present invention can be prepared as one liquid, or can be prepared by dividing into two liquids, and the two liquids can be mixed and used at the time of use. If necessary, a small amount of a curing inhibitor such as acetylene alcohol may be added.

<Hardened product>
A cured product can be obtained by curing the curable composition of the present invention.
Examples of the method for curing the curable composition of the present invention include a method in which the curable composition is applied on a substrate and then heated at 100 to 180 ° C. for 1 to 13 hours.

<Optical semiconductor device>
The optical semiconductor device of the present invention includes a semiconductor light emitting element and the cured product that covers the semiconductor light emitting element. The optical semiconductor device of the present invention is obtained by coating a semiconductor light emitting element with the curable composition and curing the composition. The method for curing the curable composition is as described above.

Examples of the optical semiconductor device include an LED (Light Emitting Diode) and an LD (Laser Diode).
FIG. 1 is a schematic view of a specific example of the optical semiconductor device of the present invention. The optical semiconductor device 1 includes an electrode 6, a semiconductor light emitting element 2 that is installed on the electrode 6 and electrically connected to the electrode 6 through a wire 7, and a reflector 3 that is disposed so as to accommodate the semiconductor light emitting element 2. The sealing material 4 is filled in the reflector 3 and seals the semiconductor light emitting element 2. The sealing material 4 is obtained by curing the curable composition of the present invention. In the sealing material 4, particles 5 such as silica and phosphor are dispersed.

  As described above, since the tack of the encapsulant (cured product) obtained by curing the curable composition of the present invention is small, there is little risk of dust and the like adhering to the encapsulant, and it is used for product selection. There is little risk of sticking between packages with the parts feeder.

1. Synthesis of polysiloxane
1-1. Structural analysis The structure of polysiloxane was analyzed by ²⁹ Si NMR and ¹³ C NMR.

1-2. Weight average molecular weight Weight average molecular weight (Mw) was measured by gel permeation chromatography (GPC) under the following conditions and was determined as a polystyrene equivalent value.
Apparatus: HLC-8120C (manufactured by Tosoh Corporation)
Column: TSK-gel Multipore HXL-M (manufactured by Tosoh Corporation)
Eluent: THF, flow rate 0.5 mL / min, load 5.0%, 100 μL

1-3. Synthesis of polysiloxane [Synthesis Example 1] Synthesis of polysiloxane (A-1) 1,3-divinyl-1,1,3,3-tetramethyl in a four-necked flask equipped with a stirrer, a reflux condenser, an inlet, and a thermometer 37.3 g of disiloxane, 234 g of phenyltrimethoxysilane, 97.7 g of diphenyldimethoxysilane, 55 g of water, 0.3 g of trifluoromethanesulfonic acid and 146 g of methylcyclohexane as a polymerization solvent were added and mixed, followed by heating under reflux for 1 hour. After cooling, the lower layer was separated and removed, and the upper methylcyclohexane solution layer was washed with water. 30 g of water, 0.3 g of potassium hydroxide and 4.4 g of 3-glycidoxypropylmethyldimethoxysilane were added to the methylcyclohexane solution layer washed with water, and the mixture was heated to reflux for 1 hour. Subsequently, methanol was distilled off and excess water was removed by azeotropic dehydration. Subsequently, the mixture was heated to reflux for 4 hours. The methylcyclohexane solution after the reaction was cooled, neutralized with 0.3 g of acetic acid and washed with water. After water removal, methylcyclohexane was distilled off under reduced pressure, the methylcyclohexane solution was concentrated, and the average unit formula was (ViMe ₂ SiO _1/2 ) ₂₀ (PhSiO _3/2 ) ₅₉ (Ph ₂ SiO _2/2 ) ₂₀ (EpMeSiO _2/2 ) ₁ (Vi is a vinyl group, Me is a methyl group, Ph is a phenyl group, and Ep is a glycidoxypropyl group.) Methyl containing polysiloxane (A-1) A cyclohexane solution was obtained. The weight average molecular weight of this polysiloxane (A-1) was 1600.

[Synthesis Example 2] Synthesis of polysiloxane (A-2) 1,3-divinyl-1,1,3,3-tetramethyldisiloxane was added to a four-necked flask equipped with a stirrer, a reflux condenser, an inlet, and a thermometer. 3 g, phenyltrimethoxysilane 234 g, diphenyldimethoxysilane 97.7 g, water 55 g, trifluoromethanesulfonic acid 0.3 g and toluene 146 g as a polymerization solvent were added and mixed, and the mixture was heated to reflux for 1 hour. After cooling, the lower layer was separated and removed, and the upper toluene solution layer was washed with water. To the toluene solution layer washed with water, 30 g of water, 0.3 g of potassium hydroxide and 4.4 g of 3-glycidoxypropylmethyldimethoxysilane were added and heated to reflux for 1 hour. Subsequently, methanol was distilled off and excess water was removed by azeotropic dehydration. Subsequently, the mixture was heated to reflux for 4 hours. The toluene solution after the reaction was cooled, neutralized with 0.3 g of acetic acid and washed with water. After removing water, toluene is distilled off under reduced pressure, and the toluene solution is concentrated. The average unit formula is (ViMe ₂ SiO _1/2 ) ₂₀ (PhSiO _3/2 ) ₅₉ (Ph ₂ SiO _2/2 ) ₂₀ (EpMeSiO _2/2 ) ₁ (Vi is a vinyl group, Me is a methyl group, Ph is a phenyl group, Ep is a glycidoxypropyl group) A toluene solution containing a polysiloxane (A-2) Obtained. The weight average molecular weight of this polysiloxane (A-2) was 1600.

[Synthesis Example 3] Synthesis of polysiloxane (D-1) 220 g of diphenyldimethoxysilane and 0.6 g of trifluoromethanesulfonic acid were added to and mixed with a stirrer, a reflux condenser, a charging port, and a four-necked flask with a thermometer. 1,3,3-tetramethyldisiloxane (60.5 g) was added, and 108 g of acetic acid was added dropwise over 30 minutes while stirring. After completion of the dropwise addition, the mixture was heated to 50 ° C. with stirring and reacted for 3 hours. Subsequently, it heated up to 80 degreeC and made it react for 2 hours. After completion of the reaction, the reaction mixture was cooled to room temperature, and then toluene and water were added, mixed well and allowed to stand, and the aqueous layer was separated and removed. The upper toluene solution layer was washed with water three times and then concentrated under reduced pressure to obtain polysiloxane (D-1) represented by the following formula (2).

Synthesis Example 4 Synthesis of Polysiloxane (A-3) 81 g of diphenyldimethoxysilane and 0.2 g of trifluoromethanesulfonic acid were added to and mixed with a stirrer, a reflux condenser, a charging port, and a four-necked flask with a thermometer. , 3-Divinyl-1,1,3,3-tetramethyldisiloxane (62 g) was added, and 60 g of acetic acid was added dropwise over 30 minutes while stirring. After completion of dropping, the mixture was stirred and heated to 50 ° C. and reacted for 3 hours. After completion of the reaction, the reaction mixture was cooled to room temperature, and then toluene and water were added, mixed well and allowed to stand, and the aqueous layer was separated and removed. The upper toluene solution layer was washed with water three times and then concentrated under reduced pressure to obtain diphenylbis (dimethylvinylsiloxy) silane (hereinafter referred to as polysiloxane (A-3)).

2. Preparation of curable composition
2-1. Content of the content methylcyclohexane and toluene methylcyclohexane was measured under the following conditions by gas disk chromatography (GC).
Equipment: Agilent Technologies 7890A
Column: DB-1701
Detector: FID.

2-2. Preparation of curable composition [Example 1]
The polycyclohexane (A-1) methylcyclohexane solution obtained in Synthesis Example 1 was concentrated to obtain a polysiloxane (A-1) -containing concentrated liquid (1). Polysiloxane (A-1) containing concentrate (1), polysiloxane (A-3), were mixed at a ratio shown below C-1, the upper Symbol D-1 and the following E-1 component in Table 1, exemplary The curable composition of Example 1 was obtained. The methylcyclohexane (component B) contained in the curable composition is derived from the polymerization solvent of Synthesis Example 1.

[Examples 2 and 3]
The polycyclohexane (A-1) having a higher degree of concentration than the polysiloxane (A-1) -containing concentrate (1) of Example 1 is concentrated by concentrating the methylcyclohexane solution of the polysiloxane (A-1) obtained in Synthesis Example 1. Contained concentrated liquid (2) and further concentrated polysiloxane (A-1) -containing concentrated liquid (3) were obtained. It shows in the following Table 1 in the procedure similar to Example 1 except having used the polysiloxane (A-1) containing concentrate (2) instead of the polysiloxane (A-1) containing concentrate (1). Each component was mixed at a ratio to obtain a curable composition of Example 2. It shows in the following Table 1 in the procedure similar to Example 1 except having used the polysiloxane (A-1) containing concentrated liquid (3) instead of the polysiloxane (A-1) containing concentrated liquid (1). Each component was mixed at a ratio to obtain a curable composition of Example 3. The methylcyclohexane (component B) contained in each curable composition is derived from the polymerization solvent of Synthesis Example 1.

[Comparative Example 1]
Toluene was distilled off from the toluene solution of polysiloxane (A-2) obtained in Synthesis Example 2 to obtain polysiloxane (A-2). Each component was mixed in the ratio shown in the following Table 1, and the curable composition of the comparative example 1 which does not contain methylcyclohexane (B component) was obtained.
The details of each component in Table 1 are as follows.

Ｃ−１：白金と１，３−ジビニル−１，１，３，３−テトラメチルジシロキサンとの錯体（白金金属量４質量％）
Ｅ−１：エチニルシクロヘキサノール

C-1: Complex of platinum and 1,3-divinyl-1,1,3,3-tetramethyldisiloxane (platinum metal amount 4% by mass)
E-1: Ethynylcyclohexanol

3. Evaluation of Curable Composition The curable compositions of Examples 1 to 3 and Comparative Example 1 were evaluated by the following methods 3-1 to 3-3. The evaluation results are shown in Table 1.

3-1. The viscosity of the viscosity curable composition was measured at 25 ° C. using an E-type viscometer.

3-2. A hard- curing composition is applied to a Teflon flat plate with a 2 mm thick frame so that it is as high as the frame, and heated in a hot air circulation oven at 150 ° C. for 5 hours to be 50 mm long, 50 mm wide, and high A 1 mm cured product was produced. The hardness of the cured product was measured with a type D durometer defined in JIS K6253.

3-3-1. Tack (evaluation by palpation)
The curable composition is put on a Teflon (trade name) flat plate with a 2 mm thick frame, applied to the height of the frame, and heated in a hot air circulation oven at 150 ° C. for 5 hours to be 50 mm long and horizontal A cured product having a height of 50 mm and a height of 1 mm was produced. The surface of this cured product was touched with a finger and the tack was evaluated according to the following criteria.
A: No stickiness
C : Sticky

3-3-2. Tack (evaluation by tack test equipment)
The curable composition was applied to a smooth substrate to a thickness of 100 μm and heated in a hot air circulation oven at 150 ° C. for 5 hours to prepare a cured product. The tack of the resulting cured product was measured with a tack tester. Details of the measurement method are as follows.
Device name: TAC-1000 (manufactured by Reska Co., Ltd.)
Terminal: SUS 10mmφ
Terminal temperature: 25 ° C
Indentation pressure: 0.05 MPa
Push-in time: 60 seconds

Claims (3)

  Containing polysiloxane (A) having an alkenyl group, methylcyclohexane and polysiloxane (D) having at least two silicon-bonded hydrogen atoms per molecule, wherein the polysiloxane (A) has an aryl group, The content of the aryl group contained in the polysiloxane (A) is 30 to 120 mol% when the number of all Si atoms contained in the polysiloxane (A) is 100 mol%, and the content ratio of methylcyclohexane is The curable composition for LED which is 0.1-1000 ppmw. An LED having a cured product obtained by curing the curable composition for LED according to claim 1 . It has a semiconductor light emitting device and the cured product covering the semiconductor light emitting device.
Item 3. The LED according to Item 2 .

Images