Curable polysiloxane composition and sealing material containing same

Abstract

(A) at least one Si-bonded alkenyl group and at least one Si-bonded aryl group per molecule, R'SiO 3 / 2 (B) a branched polysiloxane compound containing siloxane units represented by the formula (B) (R' is a substituted or unsubstituted monovalent hydrocarbon group), having at least one Si-bonded hydrogen atom and at least one Si-bonded aryl group per molecule, and having R"SiO 3 / 2 (R″ is a substituted or unsubstituted monovalent hydrocarbon group), (C) a compound that promotes the reaction between the alkenyl group of compound (A) and the hydrogen of compound (B), and (D) an inorganic filler. The present invention also provides a curable polysiloxane composition comprising the curable polysiloxane composition, and an encapsulant comprising the curable polysiloxane composition.

Description

[Technical Field]

[0001] The present invention relates to a curable polysiloxane composition and an encapsulant containing the same. [Background technology]

[0002] Light-emitting diodes (LEDs) are one of the next-generation display technologies. In recent years, as LED elements have become smaller, there has been a demand for technology that can protect the LED elements and achieve high light transmittance. Therefore, silicon materials, which have excellent thermal and optical stability, have been attracting attention as encapsulants for LED elements.

[0003] However, silicon encapsulants do not have the high transmittance required for smooth emission of light from each light source, and the intrusion of corrosive gases or water vapor can cause a deterioration in mechanical properties, leading to peeling, which reduces the effectiveness of the encapsulant.

[0004] Therefore, there is a need for research into silicon materials that can improve the effectiveness of LED element encapsulants without reducing mechanical properties while exhibiting high transmittance. Summary of the Invention [Problem to be solved by the invention]

[0005] Therefore, the present invention has been made in consideration of these problems, and one object of the present invention is to provide a curable polysiloxane composition that is excellent in transparency, transmittance, and mechanical properties, and an encapsulant containing this curable polysiloxane. [Means for solving the problem]

[0006] According to an aspect of the present invention, the above and other objects are achieved by providing (A) a polysiloxane having at least one Si-bonded alkenyl group and at least one Si-bonded aryl group per molecule, R'SiO 3 / 2(R’ is a substituted or unsubstituted monovalent hydrocarbon group) a branched polysiloxane compound containing a siloxane unit represented by, (B) having at least one Si-bonded hydrogen and at least one Si-bonded aryl group per molecule, R”SiO 3 / 2 (R” is a substituted or unsubstituted monovalent hydrocarbon group) a branched polysiloxane compound containing a siloxane unit represented by, (C) a compound that promotes the reaction between the alkenyl group of compound (A) and the hydrogen of compound (B), and (D) a curable polysiloxane composition containing an inorganic filler can be achieved by providing.

[0007] In one embodiment of the present invention, compound (A) can be represented by the following average unit formula 3. Average unit formula 1 (R 1 R 2 R 3 SiO 1 / 2 ) a (R 4 R 5 SiO 2 / 2 ) b (R 6 SiO 3 / 2 ) c (SiO 4 / 2 ) d In the formula, R 1 , R 2 and R 3 are each independently selected from substituted or unsubstituted monovalent hydrocarbon groups, and at least one of R 1 , R 2 and R 3 is an alkenyl group, and R 4 and R 5 are each independently selected from substituted or unsubstituted monovalent hydrocarbon groups and aryl groups having 6 to 12 carbon atoms, and R 6 is an aryl group having 6 to 12 carbon atoms, 0 < a < 1, 0 < b < 1, 0 < c < 1, 0 ≦ d < 1, and a + b + c + d = 1.

[0008] In one embodiment of the present invention, compound (B) can be represented by the following average unit formula 2. Average unit formula 2 (R7 R 8 R 9 SiO 1 / 2 ) e (R 10 SiO 3 / 2 ) f (R 11 SiO 3 / 2 ) g In the formula, R 7 , R 8 and R 9 are each independently selected from substituted or unsubstituted monovalent hydrocarbon groups, and at least one of R 7 , R 8 and R 9 is hydrogen, R 10 is a substituted or unsubstituted monovalent hydrocarbon group, R 11 is an aryl group having 6 to 12 carbon atoms, 0 < e < 1, 0 ≤ f < 1, 0 < g < 1, and e + f + g = 1.

[0009] In certain embodiments of the present invention, the compound (C) can include at least one of the compounds represented by the following chemical formulas 1 and 2.

[0010] Chemical formula 1

Chemical formula

[0011] Chemical formula 2

Chemical formula

[0012] In one embodiment of the present invention, the inorganic filler (D) can be contained in an amount of 0.1 to 20 parts by weight based on 100 parts by weight of the curable polysiloxane composition.

[0013] In some embodiments of the present invention, the inorganic filler (D) may include fumed silica.

[0014] In some embodiments of the present invention, the fumed silica may include a first fumed silica having a methanol value of less than 15 and a second fumed silica having a methanol value of greater than 40.

[0015] In some embodiments of the present invention, the curable polysiloxane composition may have a refractive index of 1.45 to 1.55 at wavelengths of 480 nm and 598 nm.

[0016] In one embodiment of the present invention, a cured product of the curable polysiloxane composition having a thickness of 1 mm can have a light transmittance of 80% or more.

[0017] In one embodiment of the present invention, a 1 mm thick cured product made of the curable polysiloxane composition can have a Shore D hardness of 20-40.

[0018] In accordance with another aspect of the present invention, there is provided an encapsulant comprising a curable polysiloxane composition, the curable polysiloxane composition having (A) at least one Si-bonded alkenyl group and at least one Si-bonded aryl group per molecule, R'SiO 3 / 2 (B) a branched polysiloxane compound containing siloxane units represented by the formula (B) (R' is a substituted or unsubstituted monovalent hydrocarbon group), having at least one Si-bonded hydrogen atom and at least one Si-bonded aryl group per molecule, and having R"SiO 3 / 2(R″ is a substituted or unsubstituted monovalent hydrocarbon group), (C) a compound that promotes the reaction between the alkenyl group of compound (A) and the hydrogen of compound (B), and (D) an inorganic filler.

[0019] beneficial effects The curable polysiloxane composition according to the present invention contains an inorganic filler, which can improve workability and mechanical properties.

[0020] Furthermore, the curable polysiloxane composition according to the present invention contains a branched polysiloxane compound having an alkenyl group and an aryl group, a branched polysiloxane compound having hydrogen and an aryl group, and a compound capable of forming a silicon-carbon bond by a hydrosilylation reaction. Therefore, the cured product produced from the curable polysiloxane composition can have improved adhesion and transparency while maintaining the mechanical properties of the cured product, and the cured product can exhibit a high refractive index and improve light transmittance. DETAILED DESCRIPTION OF THE INVENTION

[0021] Best form The structural or functional descriptions of the embodiments disclosed in this specification or application are merely examples for explaining embodiments according to the technical idea of the present invention, and examples according to the technical idea of the present invention may be implemented in various forms other than the embodiments disclosed in this specification or application, and the technical idea of the present invention should not be construed as being limited to the embodiments described in this specification or application.

[0022] In this specification or application, when a certain component is "comprised," it means that only that component is included, or that that component may further include other components, unless otherwise disclosed. Furthermore, all numerical ranges expressing physical property values, dimensions, etc. of components described in this specification or application should be understood to be modified in all cases by the term "about" unless otherwise specified.

[0023] In addition, the meanings of the terms used in this specification or application are as follows: Siloxane: A compound containing an Si-O-Si bond. Polysiloxane: A compound containing multiple Si-O-Si bonds. Polysiloxane composition: A composition consisting solely of polysiloxane compounds, or a composition containing polysiloxanes mixed with additional compounds to achieve specific performance properties. Linear polysiloxane: A polysiloxane with a structure in which the siloxane chain is not linked by interposing an atomic linking group between the Si atoms of the polysiloxane main chain (-Si-O-Si-O-). Branched polysiloxane: A polysiloxane containing at least one T-shaped or cross-shaped branch point. Organopolysiloxane: A polysiloxane having a structure in which organic groups are bonded to the Si atoms that make up the Si-O-Si bond.

[0024] <Curable Polysiloxane Composition> The curable polysiloxane composition of the present invention comprises (A) a polysiloxane having at least one Si-bonded alkenyl group and at least one Si-bonded aryl group per molecule, and R'SiO 3 / 2 (B) a branched polysiloxane compound containing siloxane units represented by the formula (B) (R' is a substituted or unsubstituted monovalent hydrocarbon group), having at least one Si-bonded hydrogen atom and at least one Si-bonded aryl group per molecule, and having R"SiO 3 / 2 (R″ is a substituted or unsubstituted monovalent hydrocarbon group), (C) a compound that promotes the reaction between the alkenyl group of compound (A) and the hydrogen of compound (B), and (D) an inorganic filler.

[0025] <Component (A)> The curable polysiloxane composition of the present invention comprises (A) a polysiloxane having at least one Si-bonded alkenyl group and at least one Si-bonded aryl group per molecule, and R'SiO 3 / 2 (R' is a substituted or unsubstituted monovalent hydrocarbon group).

[0026] Component (A) can impart strength and an increased refractive index to the cured product obtained by curing the curable polysiloxane composition. Specifically, when the curable polysiloxane composition contains component (A), the thermal shock resistance of the cured product can be improved, and the refractive index can be increased, thereby improving the light transmittance.

[0027] Component (A) contains a branched polysiloxane compound having a -Si-O-Si-O- (polysiloxane) main chain and containing at least one T-type or cross-type branch point per molecule. Preferably, component (A) may contain only branched polysiloxane compounds, but it may also exclude linear polysiloxane compounds having a structure in which siloxane chains are not linked by inserting an atomic linking group into the Si atom of the polysiloxane main chain (-Si-O-Si-O-). Because component (A) does not contain a linear polysiloxane compound, the transparency of the cured product of the curable polysiloxane compound is improved, and the light transmittance is improved due to the higher refractive index.

[0028] In component (A), the alkenyl group may be vinyl, allyl, methallyl, butenyl, pentenyl, or hexenyl. Preferably, the alkenyl group is vinyl.

[0029] In component (A), the aryl group can be phenyl, naphthyl, anthryl, phenanthryl, indenyl, benzophenyl, fluorenyl, xanthenyl, anthronyl, aryloxyaryl, o-phenoxyphenyl, p-phenoxyphenyl, alkaryl, o-tolyl, m-tolyl, p-tolyl, xylyl, ethylphenyl, aralkyl, benzyl, α-phenylethyl, or β-phenylethyl. Preferably, the aryl group can be phenyl.

[0030] In component (A), the Si-bonded organic group other than an alkenyl group and an aryl group may be a substituted or unsubstituted monovalent hydrocarbon group, specifically, it may be methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, or halogenated alkyl. Preferably, the Si-bonded organic group can be methyl.

[0031] In component (A), R′SiO 3 / 2 The siloxane unit represented by can mean a branched polysiloxane compound having a T-type or cross-type branch point. R′ is a substituted or unsubstituted monovalent hydrocarbon group. The substituent of the monovalent hydrocarbon group can be alkyl, alkenyl, aryl, aralkyl, or halogenated alkyl.

[0032] Component (A) can be represented by the following average unit formula 3. Average unit formula 1 (R 1 R 2 R 3 SiO 1 / 2 ) a (R 4 R 5 SiO 2 / 2 ) b (R 6 SiO 3 / 2 ) c (SiO 4 / 2 ) d

[0033] In average unit formula 1, R 1 , R 2 and R 3 [[ID=5i]]are each independently selected from substituted or unsubstituted monovalent hydrocarbon groups, at least one of R 1 , R 2 and R 3 is an alkenyl group, and R 4 and R 5 are each independently selected from substituted or unsubstituted monovalent hydrocarbon groups and aryl groups having 6 to 12 carbon atoms, and R 6 is an aryl group having 6 to 12 carbon atoms, 0 < a < 1, 0 < b < 1, 0 < c < 1, 0 ≤ d < 1, and a + b + c + d = 1.

[0034] The substituent of the monovalent hydrocarbon group can be alkyl, alkenyl, aryl, aralkyl, or halogenated alkyl.

[0035] The alkenyl group can be vinyl, allyl, methallyl, butenyl, pentenyl, or hexenyl.

[0036] The aryl group having 6 to 12 carbon atoms can be a phenyl group or a naphthyl group.

[0037] a can be 0 < a < 1, 0 < a < 0.8, 0 < a < 0.5, 0 < a < 0.3, or 0 < a < 0.2.

[0038] b can be 0 < b < 1, 0.1 < b < 1, 0.1 < b < 0.9, 0.2 < b < 0.8, or 0.3 < b < 0.7.

[0039] c can be 0 < c < 1, 0 < c < 0.8, 0 < c < 0.5, 0.1 < c < 0.5, or 0.2 < c < 0.5.

[0040] d can be 0 ≤ d < 1, 0 ≤ d < 0.5, 0 ≤ d < 0.3, 0 ≤ d < 0.2, or 0 ≤ d < 0.1.

[0041] R 1 、R 2 、R 3 、R 4 、R 5 及びR 6 Based on the total amount of R

[0042] R 1 、R 2 、R 3 、R 4 、R 5 及びR 6Based on the total amount of the curable polysiloxane composition, the aryl group content may be 10 mol % to 90 mol %, 20 mol % to 90 mol %, 30 mol % to 90 mol %, 30 mol % to 80 mol %, or 40 mol % to 70 mol %. Within these ranges, phenomena such as light refraction, reflection, and scattering in a cured product prepared from the curable polysiloxane composition are reduced, so that the transparency and transmittance can be further improved.

[0043] Component (A) can exist in the liquid or solid state at 25°C.

[0044] Based on the total weight of the curable polysiloxane composition, the content of component (A) can be 20% to 90% by weight, 30% to 90% by weight, 35% to 90% by weight, 40% to 90% by weight, or 45% to 60% by weight.

[0045] <Ingredient (B)> The curable polysiloxane composition of the present invention comprises (B) a polysiloxane having at least one Si-bonded hydrogen and at least one Si-bonded aryl group per molecule, R″SiO 3 / 2 (R″ is a substituted or unsubstituted monovalent hydrocarbon group).

[0046] Component (B) can be used as a curing agent for the curable polysiloxane composition. Specifically, when the curable polysiloxane composition contains component (B), the curing reaction with component (A) via hydrosilylation can proceed efficiently.

[0047] Component (B) contains a branched polysiloxane compound having a -Si-O-Si-O- (polysiloxane) main chain and containing at least one T-type or cross-type branch point per molecule. Preferably, component (B) may contain only branched polysiloxane compounds, but it may also exclude linear polysiloxane compounds having a structure in which siloxane chains are not linked by inserting an atomic linking group into the Si atom of the polysiloxane main chain (-Si-O-Si-O-). Because component (B) does not contain a linear polysiloxane compound, it can improve the mechanical properties and transparency of cured products prepared from the curable polysiloxane compound.

[0048] In component (B), the aryl group can be phenyl, naphthyl, anthryl, phenanthryl, indenyl, benzophenyl, fluorenyl, xanthenyl, anthronyl, aryloxyaryl, o-phenoxyphenyl, p-phenoxyphenyl, alkaryl, o-tolyl, m-tolyl, p-tolyl, xylyl, ethylphenyl, aralkyl, benzyl, α-phenylethyl, or β-phenylethyl. Preferably, the aryl group can be phenyl.

[0049] In component (B), the Si-bonded organic group other than hydrogen and the aryl group may be a substituted or unsubstituted monovalent hydrocarbon group, specifically, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, or a halogenated alkyl. Preferably, the Si-bonded organic group is methyl.

[0050] In component (B), R″SiO 3 / 2 The siloxane unit represented by the formula (I) can refer to a branched polysiloxane compound having T-shaped or cross-shaped branching points. R' is a substituted or unsubstituted monovalent hydrocarbon group. The substituent of the monovalent hydrocarbon group can be an alkyl, alkenyl, aryl, aralkyl, or halogenated alkyl.

[0051] Component (B) can be represented by the following average unit formula 2.

[0052] Average Unit Formula 2 (R 7 R 8 R 9 SiO 1 / 2 ) e (R (R 10 SiO 3 / 2 ) f (R 11 SiO 3 / 2 ) g

[0053] In the average unit formula 2, R 7 , R 8 and R 9 are each independently selected from substituted or unsubstituted monovalent hydrocarbon groups, and at least one of R 7 , R 8 and R 9 is hydrogen, R 10 is a substituted or unsubstituted monovalent hydrocarbon group, R 11 is an aryl group having 6 to 12 carbon atoms, 0 < e < 1, 0 ≤ f < 1, 0 < g < 1, and e + f + g = 1.

[0054] The substituent of the monovalent hydrocarbon group can be alkyl, alkenyl, aryl, aralkyl, or halogenated alkyl.

[0055] The aryl group having 6 to 12 carbon atoms can be a phenyl group or a naphthyl group.

[0056] e can be 0 < e < 1, 0 < e < 0.8, 0.1 < e < 0.8, 0.2 < e < 0.7, or 0.2 < e < 0.6.

[0057] f can be 0 ≤ f < 1, 0 ≤ f < 0.8, 0 ≤ f < 0.7, 0 ≤ f < 0.6, or 0 ≤ f < 0.5.

[0058] g can be 0 < g < 1, 0 < g < 0.9, 0.1 < g < 0.9, 0.1 < g < 0.8, or 0.2 < g < 0.8.

[0059] [[ID=;66]]R 7 , R 8 , R 9 , R10 and R 11 The hydrogen content may be 0.1 mol % to 40 mol %, 1 mol % to 40 mol %, 3 mol % to 40 mol %, 3 mol % to 40 mol %, or 5 mol % to 40 mol %, based on the total amount of (A). Within these ranges, the curing reaction with component (A) via hydrosilylation can proceed more efficiently.

[0060] R 7 , R 8 , R 9 , R 10 and R 11 Based on the total amount of the curable polysiloxane composition, the aryl group content may be 10 mol % to 90 mol %, 20 mol % to 90 mol %, 30 mol % to 90 mol %, 30 mol % to 80 mol %, or 40 mol % to 70 mol %. Within these ranges, phenomena such as light refraction, reflection, and scattering in a cured product made from the curable polysiloxane composition are reduced, thereby further improving transparency and transmittance.

[0061] Based on the total weight of the curable polysiloxane composition, the content of component (B) may be 10% by weight to 80% by weight, 10% by weight to 70% by weight, 10% by weight to 60% by weight, 10% by weight to 50% by weight, or 20% by weight to 50% by weight.

[0062] The molar ratio of Si-bonded hydrogen in component (B) to Si-bonded alkenyl groups in component (A) can be 0.7 to 1.0, which can reduce the content of silicon hydride residues and improve the adhesiveness of cured products made from the curable polysiloxane composition.

[0063] <Component (C)> The curable polysiloxane composition of the present invention includes a compound (C) that promotes the reaction between the alkenyl groups of compound (A) and the hydrogen of compound (B).

[0064] Component (C) can increase the hardness of a cured product prepared from the curable polysiloxane composition without changing the content of the branched polysiloxane compound in components (A) and (B). In addition, component (C) can increase the refractive index of a cured product prepared from the curable polysiloxane composition without changing the content of the branched polysiloxane compound in components (A) and (B).

[0065] Component (C) may form a complex compound in combination with a catalyst that promotes the reaction between the alkenyl group of compound (A) and the hydrogen of compound (B) (hydrosilylation reaction).

[0066] The catalyst may include a platinum catalyst, a rhodium catalyst, or a palladium catalyst.

[0067] The complex compound can be a platinum / alkenylsiloxane complex compound, a platinum / olefin complex compound, or a platinum / carbonyl complex compound.

[0068] Component (C) may contain at least one of compounds represented by the following Chemical Formula 1 and Chemical Formula 2.

[0069] chemical formula 1 [ka]

[0070] chemical formula 2 [ka]

[0071] In Formula 1, R 12 , R 13 and R 14 are each independently an alkenyl group having 2 to 20 carbon atoms. 15 , R 16 , R 17 and R 18 are each independently a substituted or unsubstituted monovalent hydrocarbon group, and R19 , R 20 , R 21 and R 22 are each independently an alkenyl group having 2 to 20 carbon atoms.

[0072] The compound represented by Chemical Formula 1 may be a compound represented by Chemical Formula 1-1 below.

[0073] Chemical formula 1-1 [ka]

[0074] The compound represented by Chemical Formula 2 may be a compound represented by the following Chemical Formula 2-1.

[0075] Chemical formula 2-1 [ka]

[0076] Based on the total weight of the curable polysiloxane composition, the content of component (C) can be 1 wt % to 30 wt %, 1 wt % to 25 wt %, 1 wt % to 20 wt %, 1 wt % to 18 wt %, or 1 wt % to 15 wt %.

[0077] Based on the total weight of the curable polysiloxane composition, the catalyst content can be 0.1 ppm to 10 ppm, 0.1 ppm to 8 ppm, 0.1 ppm to 7 ppm, 1 ppm to 7 ppm, or 1 ppm to 5 ppm.

[0078] <Ingredient (D)> The curable polysiloxane composition according to the present invention contains (D) an inorganic filler.

[0079] Component (D) can improve the workability and mechanical properties of the cured product prepared from the curable polysiloxane composition.

[0080] Examples of inorganic fillers include inorganic oxide particles such as silica, barium titanate, titanium oxide, zirconium oxide, niobium oxide, aluminum oxide, cerium oxide, and yttrium oxide; nitride particles such as silicon nitride, boron nitride, silicon carbide, and aluminum nitride; carbon compound particles; and diamond particles.

[0081] The inorganic filler may include fumed silica.

[0082] Fumed silica is a commercially available product or can be prepared by standard chemical processes. Fumed silica can be prepared by the hydrolysis or oxidation of volatile chlorosilanes in a hydrogen / oxygen gas flame.

[0083] The fumed silica may comprise a first fumed silica having a methanol value of less than 15 and a second fumed silica having a methanol value of greater than 40; preferably, the first fumed silica may have a methanol value of 0 and the second fumed silica may have a methanol value of greater than 50.

[0084] The methanol value may refer to the percentage by weight of methanol in a water / methanol mixture at which approximately 50% of the fumed silica is wet and submerged in the liquid at 25° C. and 1013 hPa.

[0085] The methanol value can be determined in the following way: Equal volumes of each fumed silica are added to a water / methanol mixture at 25°C and 1013 hPa. The mixture is then mixed for 5 minutes and then aged for 10 minutes. The amount of silica precipitated in the mixture is then measured. If no fumed silica precipitates in the mixture when observed with the naked eye, the experiment is repeated.

[0086] The first fumed silica may refer to a relatively hydrophilic silica, and the second fumed silica may refer to a relatively hydrophobic silica. Component (D) contains both hydrophilic and hydrophobic silica, and therefore can increase the hardness of the curable polysiloxane composition, thereby improving mechanical properties, thermal shock resistance, moldability, and workability.

[0087] The content of component (D) can be 0.1 to 20 parts by weight, 1 to 20 parts by weight, 1 to 18 parts by weight, or 3 to 10 parts by weight, relative to 100 parts by weight of the curable polysiloxane composition. Within these ranges, mechanical properties can be improved without impairing transparency and light transmittance.

[0088] <Other additives> If necessary, the curable polysiloxane composition of the present invention may further contain a curing inhibitor, phosphorus, a fine powder of polymethacrylate resin, a heat stabilizer, a dye, a pigment, a flame retardant, a solvent, and the like.

[0089] Additionally, the curable polysiloxane composition may further include a tackifier to enhance adhesion.

[0090] Examples of tackifiers include epoxy silanes, such as glycidoxypropyltrimethoxysilane, glycidoxypropylmethyldimethoxysilane, glycidoxypropyltriethoxysilane, or glycidoxypropylmethyldiethoxysilane, 2-(3-triethoxysilylpropyl)maleic anhydride, N-(3-trimethoxysilylpropyl)urea, N-(3-triethoxysilylpropyl)urea, N-(trimethoxysilylmethyl)urea, N-(methyldimethoxysilylmethyl)urea, O-(methylcarbamatomethyl)methyldimethoxysilane, O-(methylcarbatomethyl)tri Examples of suitable silanes include methoxysilane, O-(ethylcarbamatomethyl)methyl-diethoxysilane, O-(ethylcarbamatomethyl)triethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, methacryloyloxymethyltrimethoxysilane, methacryloyloxymethylmethyldimethoxysilane, methacryloyloxymethyltriethoxysilane, methacryloyloxymethylmethyldiethoxysilane, 3-acryloyloxypropyltrimethoxysilane, acryloyloxymethyltrimethoxysilane, and acryloyloxymethylmethyldimethoxysilane.

[0091] Based on the total weight of the curable polysiloxane composition, the tackifier content can be 0.1 wt % to 10 wt %, 0.1 wt % to 5 wt %, 0.1 wt % to 3 wt %, or 0.1 wt % to 2 wt %.

[0092] <Physical Properties of Curable Polysiloxane Composition> The curable polysiloxane composition may have a refractive index of 1.45 to 1.55 at wavelengths of 480 nm and 598 nm. The refractive index can be measured using an Abbe refractometer at D-line wavelengths (480 nm, 589 nm) of a cured product prepared from the curable polysiloxane composition or the pre-cured composition. If the refractive index is within this range, the transparency and mechanical properties of a cured product prepared from the curable polysiloxane composition can be improved.

[0093] A cured product of the curable polysiloxane composition having a thickness of 1 mm can have a light transmittance of 80% or more, 82% or more, 84% or more, 86% or more, 88% or more, or 90% or more. When the light transmittance is within this range, when the cured product of the curable polysiloxane composition is used as an LED encapsulant, light can be emitted smoothly from each light source.

[0094] A 1 mm-thick cured product prepared from the curable polysiloxane composition may have a Shore D hardness of 20 to 40, 22 to 40, 24 to 40, 26 to 40, or 28 to 40. The Shore D hardness of the cured product can be measured with a Shore D hardness tester by injecting the curable polysiloxane composition into a Teflon®-coated mold measuring 4 cm wide, 5 cm long, and 6 mm thick, curing at 190°C for 10 minutes, and then cooling at room temperature to produce a cured product. When the Shore D hardness is within these ranges, the mechanical properties and thermal shock resistance of the cured product of the curable polysiloxane composition can be improved.

[0095] <Sealing material> The sealing material according to the present invention comprises (A) a compound having at least one Si-bonded alkenyl group and at least one Si-bonded aryl group per molecule, and R'SiO 3 / 2 (B) a branched polysiloxane compound containing siloxane units represented by the formula (B) (R' is a substituted or unsubstituted monovalent hydrocarbon group), having at least one Si-bonded hydrogen atom and at least one Si-bonded aryl group per molecule, and having R"SiO 3 / 2 (R″ is a substituted or unsubstituted monovalent hydrocarbon group), (C) a compound that promotes the reaction between the alkenyl group of compound (A) and the hydrogen of compound (B), and (D) an inorganic filler.

[0096] Components (A) to (D) of the curable polysiloxane composition can be the same as components (A) to (D) described above.

[0097] The sealing material can have a film or sheet shape obtained by curing a curable polysiloxane composition.

[0098] The encapsulant can be used as an encapsulant for displays or semiconductors.

[0099] The encapsulant may be provided in a form that encapsulates, covers, or adheres to a display optical element or a semiconductor optical element, which may be a light emitting diode (LED).

[0100] Because light-emitting diodes (LEDs) emit light from the top, bottom, left, and right of the optical element, it is undesirable for the encapsulant to absorb light, and the encapsulant must exhibit high light transmittance. Furthermore, light-emitting diodes (LEDs) require stability against high temperatures and mechanical shock, so the encapsulant must have thermal stability and mechanical properties. Therefore, as described above, the curable polysiloxane composition according to the present invention has high transparency, optical transmittance, and mechanical properties. Therefore, when a cured product prepared from the curable polysiloxane composition is used as an encapsulant, excellent optical transmittance, thermal stability, and mechanical properties can be achieved.

[0101] The present invention will be described in more detail below with reference to examples and comparative examples, but the following examples and comparative examples are merely examples for explaining the present invention in more detail, and the present invention is not limited by the following examples and comparative examples. [Example]

[0102] The following components and compositions shown in Table 1 were used to prepare the curable polysiloxane compositions of Examples 1 to 6 and Comparative Examples 1 to 5.

[0103] Synthesis of component (a-1): 1 kg of a mixed solvent obtained by mixing water and toluene in a weight ratio of 1:9 was placed in a three-necked flask. A monomer mixture with a molar ratio of vinyldimethylchlorosilane:dimethyldichlorosilane:phenyltrichlorosilane of 1:6:3 was added to the flask while maintaining the temperature at 23°C. Next, condensation polymerization was carried out under reflux at 60°C for 3 hours. Next, the flask was cooled to room temperature, and the water (HO) layer was removed to prepare a solution. The solution was dissolved in toluene. Next, this solution was washed with water to remove chlorine as a by-product. Next, the neutral solution was distilled under reduced pressure to remove the toluene, yielding a branched polysiloxane compound represented by the following average unit formula: - Average unit formula of component (a-1) (Me2ViSiO 1 / 2 ) 0.11 (DiMeSiO 2 / 2 ) 0.63 (PhSiO 3 / 2 ) 0.26

[0104] Synthesis of component (a-2): 1 kg of a mixed solvent obtained by mixing water and toluene in a weight ratio of 1:9 was placed in a three-necked flask. A monomer mixture with a molar ratio of vinyldimethylchlorosilane:methylphenyldichlorosilane:phenyltrichlorosilane of 2:3:5 was added to the flask while maintaining the temperature at 23°C. Next, condensation polymerization was carried out under reflux at 60°C for 3 hours. Next, the flask was cooled to room temperature, and the water (HO) layer was removed to prepare a solution. The solution was dissolved in toluene. Next, this solution was washed with water to remove chlorine as a by-product. Next, the neutral solution was distilled under reduced pressure to remove the toluene, yielding a branched polysiloxane compound represented by the following average unit formula: - Average unit formula of component (a-2) (Me2ViSiO 1 / 2 ) 0.23 (MePhSiO 2 / 2 ) 0.32 (PhSiO 3 / 2 ) 0.45

[0105] Synthesis of component (a-3): 1 kg of a mixed solvent obtained by mixing water and toluene in a weight ratio of 1:9 was placed in a three-necked flask. A monomer mixture with a molar ratio of vinyldimethylchlorosilane:methylphenyldichlorosilane:phenyltrichlorosilane of 1:2:7 was added to the flask while maintaining the temperature at 23°C. Next, condensation polymerization was carried out under reflux at 90°C for 3 hours. Next, the flask was cooled to room temperature, and the water (HO) layer was removed to prepare a solution. The solution was dissolved in toluene. Next, this solution was washed with water to remove chlorine as a by-product. Next, the neutral solution was distilled under reduced pressure to remove the toluene, yielding a branched polysiloxane compound represented by the following average unit formula: - Average unit formula of component (a-3) (Me2ViSiO 1 / 2 ) 0.11 (MePhSiO 2 / 2 ) 0.21 (PhSiO 3 / 2 ) 0.68

[0106] Component (a-4): A linear polysiloxane compound represented by the following average unit formula: - Average unit formula of component (a-4) is ViMe2SiO(Me2SiO) 20 SiMe2Vi

[0107] Synthesis of component (b-1): 500 g of a mixed solvent obtained by mixing water and toluene in a weight ratio of 1:9 was placed in a three-necked flask. A monomer mixture with a molar ratio of dimethylchlorosilane:phenyltrichlorosilane:methyltrichlorosilane of 3.5:2.5:4 was added to the flask while maintaining the temperature at 23°C. Next, condensation polymerization was carried out under reflux at 30°C for 3 hours. Next, the flask was cooled to room temperature, and the water (HO) layer was removed to prepare a solution. The solution was dissolved in toluene. Next, this solution was washed with water to remove chlorine as a by-product. Next, the neutral solution was distilled under reduced pressure to remove the toluene, yielding a branched polysiloxane compound represented by the following average unit formula: - Average unit formula of component (b-1) (HMe2SiO 1 / 2 ) 0.35 (MeSiO 3 / 2 ) 0.40(PhSiO 3 / 2 ) 0.25

[0108] Synthesis of component (b-2): 500 g of a mixed solvent obtained by mixing water and toluene in a weight ratio of 1:9 was placed in a three-necked flask. A monomer mixture with a molar ratio of dimethylchlorosilane:phenyltrichlorosilane of 4.5:5.5 was added to the flask while maintaining the temperature at 23°C. Next, condensation polymerization was carried out under reflux at 30°C for 1 hour. Next, the flask was cooled to room temperature, and the water (HO) layer was removed to prepare a solution. The solution was dissolved in toluene. Next, this solution was washed with water to remove chlorine as a by-product. Next, the neutral solution was distilled under reduced pressure to remove the toluene, yielding a branched polysiloxane compound represented by the following average unit formula: - Average unit formula of component (b-2) (HMe2SiO 1 / 2 ) 0.44 (PhSiO 3 / 2 ) 0.56

[0109] Synthesis of component (b-3): 500 g of a mixed solvent obtained by mixing water and toluene in a weight ratio of 1:9 was placed in a three-necked flask. A monomer mixture with a molar ratio of dimethylchlorosilane:phenyltrichlorosilane:methyltrichlorosilane of 2:1:7 was added to the flask while maintaining the temperature at 23°C. Next, condensation polymerization was carried out under reflux at 30°C for 3 hours. Next, the flask was cooled to room temperature, and the water (HO) layer was removed to prepare a solution. The solution was dissolved in toluene. Next, this solution was washed with water to remove chlorine as a by-product. Next, the neutral solution was distilled under reduced pressure to remove the toluene, yielding a branched polysiloxane compound represented by the following average unit formula: - Average unit formula of component (b-3) (HMe2SiO 1 / 2 ) 0.21 (MeSiO 3 / 2 ) 0.71 (PhSiO 3 / 2 ) 0.08

[0110] Component (b-4): A linear polysiloxane compound represented by the following average unit formula: - Average unit formula of component (b-4) HMe2SiO(Ph2SiO)SiMe2H

[0111] Component (c-1): A compound represented by the following chemical formula 1-1

[0112] Chemical formula 1-1 [ka]

[0113] Component (c-2): A compound represented by the following chemical formula 2-1

[0114] Chemical formula 2-1 [ka]

[0115] Component (d-1): Fumed silica (methanol value: 0, specific surface area: 150 m 2 / g)

[0116] Component (d-2): Fumed silica (methanol value: 75, specific surface area: 150 m 2 / g)

[0117] Component (e): Tackifier (GF80, manufactured by GENIOSIL)

[0118] Component (f): Catalyst (Pt-CS2.0, manufactured by Unicore)

[0119] <Experimental Example> Experimental Example 1 - Viscosity Measurement The viscosity of the compositions of Examples 1 to 6 and Comparative Examples 1 to 5 before curing was measured at 25° C. and a shear rate of 10 / sec according to ISO 3219, and the results are shown in Table 1 below.

[0120] Experimental Example 2 - Refractive Index Measurement Before curing, the refractive index of the compositions of Examples 1 to 6 and Comparative Examples 1 to 5 was measured at D-line wavelengths (480 nm, 589 nm) using an Abbe refractometer, and the results are shown in Table 1 below.

[0121] Experimental example 3 - Confirmation of agglomerated particles Before curing, each of the compositions of Examples 1 to 6 and Comparative Examples 1 to 5 was placed on a slide glass, compressed, and visually observed under a microscope for the occurrence of agglomerated particles. The results are shown in Table 1 below.

[0122] Experimental example 4 - Dome lens shape confirmation Before curing, each of the compositions of Examples 1 to 6 and Comparative Examples 1 to 5 was dispensed onto a PCB substrate with a dome lens shape measuring approximately 2.5 mm using a jet dispenser. The side surfaces of each of the dome lenses of Examples 1 to 6 and Comparative Examples 1 to 5 were observed under a microscope and evaluated according to the following criteria. The results are shown in Table 1 below. - ◎: The height is 0.5mm to 1mm, and the dome shape is not distorted or biased. - ○: The height is 0.5mm to 1mm, and the dome shape is distorted or biased - X: The height is less than 0.5 mm and the dome shape is distorted or biased

[0123] Experimental Example 5 - Hardness measurement Each composition of Examples 1 to 6 and Comparative Examples 1 to 5 was placed in a Teflon®-coated mold measuring 4 cm wide x 5 cm long x 6 mm thick, cured at 190°C for 10 minutes, and then cooled to room temperature. The hardness of the cured product was then measured using a Shore D hardness tester, and the results are shown in Table 1 below.

[0124] Experimental Example 6 - Transparency evaluation The transparency of the cured product produced in Experimental Example 5 was evaluated according to the following criteria, and the results are shown in Table 1 below. - ◎: The entire cured product is transparent when observed with the naked eye - ○: Part of the cured material is opaque when observed with the naked eye - X: The entire cured product is opaque when observed with the naked eye.

[0125] Experimental Example 7 - Surface smoothness evaluation The surface of the cured product produced in Experimental Example 5 was visually observed under a microscope and evaluated according to the following criteria. The results are shown in Table 1 below. - ○: No wrinkles are observed on the surface of the cured product - X: Wrinkles are observed on the surface of the cured product.

[0126] Experimental Example 8 - Transmittance Measurement Each of the compositions of Examples 1 to 6 and Comparative Examples 1 to 5 was placed in a Teflon®-coated mold measuring 4 cm wide x 5 cm long x 1 mm thick, cured at 190°C for 10 minutes, and then cooled to room temperature. The transmittance (based on a wavelength of 450 nm) of each cured product was then measured using a Specord 200 Plus UV-Vis spectrometer, and the results are shown in Table 1 below.

[0127] Experimental Example 9 - Heat Shock Evaluation Thermal Shock Evaluation One hundred droplets of the composition of Example 1 were dispensed onto a PCB substrate using a jet dispenser in the form of dome lenses approximately 2.5 mm in size, then thermally cured at 190°C for 10 minutes, and then cooled at room temperature to produce 100 dome lens shapes. In addition, 100 dome lenses were produced from each of the compositions of Examples 2 to 6 and Comparative Examples 1 to 5 in the same manner as in Example 1.

[0128] One cycle consisted of exposing the dome lens to a low-temperature (-45°C) chamber and a high-temperature (125°C) chamber for 15 minutes each. After 200 cycles, the dome lens was checked to see if it had peeled off from the PCB substrate. The heat shock was evaluated according to the following criteria, and the results are shown in Table 1 below. - ◎: The dome lens did not come off from the board. - ○: No dome lenses peeled off from the substrate, but some dome lenses exhibited floating phenomenon. - X: Dome lens peeled off from the board

[0129] Experimental Example 10 - Adhesion Strength Measurement Each of the compositions of Examples 1 to 6 and Comparative Examples 1 to 5 was dispensed onto a PCB substrate using a jet dispenser in the form of a dome lens with a size of approximately 2.5 mm, and then thermally cured for 10 minutes at 190° C. Next, the adhesive strength between the dome lens and the PCB substrate was measured using a die shear tester under the following conditions. - Test speed: 700μm / sec - Shear height: 30 μm - Test load: 400g - Maximum test load: 5,000g

[0130] [Table 1] TIFF2025526543000010.tif250169

[0131] Referring to Table 1, it can be seen that Examples 1 to 6 exhibit excellent transparency, light transmittance, adhesiveness and mechanical properties.

[0132] It can be seen that in Comparative Examples 1 and 2, the transparency is lower than in Examples 1 to 6, and in particular the light transmittance is significantly lower. It can also be seen that in Comparative Example 3, the transparency and light transmittance are significantly lower than in Examples 1 to 6.

[0133] In Comparative Example 4, it can be confirmed that the transparency, thermal shock resistance and adhesive strength are lower than those in Examples 1 to 6, and the surface properties are non-uniform.

[0134] It can be seen that Comparative Example 5 does not show a decrease in transparency and light transmittance compared to Examples 1 to 6, but the mechanical properties and thermal shock resistance are significantly decreased.

[0135] In conclusion, it has been confirmed that when the cured products prepared from the compositions of Comparative Examples 1 to 5 are used as encapsulants for light-emitting diodes (LEDs), the durability of the encapsulant may be reduced or the encapsulant may absorb a large amount of light, resulting in reduced product reliability.

Claims

1. 1. A curable polysiloxane composition comprising: (A) at least one Si-bonded alkenyl group and at least one Si-bonded aryl group per molecule, R'SiO ３／２ (R' is a substituted or unsubstituted monovalent hydrocarbon group), (B) at least one Si-bonded hydrogen and at least one Si-bonded aryl group per molecule, R″SiO ３／２ (R″ is a substituted or unsubstituted monovalent hydrocarbon group), (C) a compound that promotes the reaction between the alkenyl group of compound (A) and the hydrogen of compound (B), and (D) Inorganic filler.

2. 2. The curable polysiloxane composition according to claim 1, wherein the compound (A) is represented by the following average unit formula 3: Average Unit Formula 1 (R １ R ２ R ３ SiO １／２ ) ａ (R ４ R ５ SiO ２／２ ) ｂ (R ６ SiO ３／２ ) ｃ (SiO ４／２ ) ｄ [In the formula, R １ , R ２ and R ３ are each independently selected from substituted or unsubstituted monovalent hydrocarbon groups; R １ , R ２ and R ３ At least one of R is an alkenyl group; ４ and R ５ are each independently selected from substituted or unsubstituted monovalent hydrocarbon groups and aryl groups having 6 to 12 carbon atoms; R ６ is an aryl group having 6 to 12 carbon atoms, 0<a<1, 0<b<1, 0<c<1, 0≦d<1, and a+b+c+d=1.

3. 2. The curable polysiloxane composition according to claim 1, wherein the compound (B) is represented by the following average unit formula 2: Average Unit Formula 2 (R ７ R ８ R ９ SiO １／２ ) ｅ (R １０ SiO ３／２ ) ｆ (R １１ SiO ３／２ ) ｇ [In the formula, R ７ , R ８ and R ９ are each independently selected from substituted or unsubstituted monovalent hydrocarbon groups; R ７ , R ８ and R ９ at least one of R １０ is a substituted or unsubstituted monovalent hydrocarbon group, and R １１ is an aryl group having 6 to 12 carbon atoms, 0<e<1, 0≦f<1, 0<g<1, and e+f+g=1.

4. 2. The curable polysiloxane composition according to claim 1, wherein the compound (C) comprises at least one of compounds represented by the following chemical formulas 1 and 2: Chemical formula 1 【Chemical 1】 chemical formula 2 【Chemistry 2】 [In Chemical Formula 1, R １２ , R １３ and R １４ are each independently an alkenyl group having 2 to 20 carbon atoms; In Chemical Formula 2, R １５ , R １６ , R １７ and R １８ are each independently a substituted or unsubstituted monovalent hydrocarbon group, R １９ , R ２０ , R ２１ and R ２２ are each independently an alkenyl group having 2 to 20 carbon atoms.

5. 2. The curable polysiloxane composition according to claim 1, wherein the inorganic filler (D) is contained in an amount of 0.1 to 20 parts by weight per 100 parts by weight of the curable polysiloxane composition.

6. 2. The curable polysiloxane composition of claim 1, wherein the inorganic filler (D) comprises fumed silica.

7. 7. The curable polysiloxane composition of claim 6, wherein the fumed silica comprises a first fumed silica having a methanol value of less than 15 and a second fumed silica having a methanol value of greater than 40.

8. 2. The curable polysiloxane composition of claim 1, which has a refractive index of 1.45 to 1.55 at wavelengths of 480 nm and 598 nm.

9. 2. The curable polysiloxane composition according to claim 1, wherein a cured product having a thickness of 1 mm made from the curable polysiloxane composition has a light transmittance of 80% or more.

10. 2. The curable polysiloxane composition according to claim 1, wherein a cured product having a thickness of 1 mm made from the curable polysiloxane composition has a Shore D hardness of 20 to 40.

11. 1. An encapsulant comprising a curable polysiloxane composition comprising: (A) at least one Si-bonded alkenyl group and at least one Si-bonded aryl group per molecule, R'SiO ３／２ (R' is a substituted or unsubstituted monovalent hydrocarbon group), (B) at least one Si-bonded hydrogen and at least one Si-bonded aryl group per molecule, R″SiO ３／２ (R″ is a substituted or unsubstituted monovalent hydrocarbon group), (C) a compound that promotes the reaction between the alkenyl group of compound (A) and the hydrogen of compound (B), and (D) Inorganic filler.

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