Thermally curable silicone composition

Abstract

This invention provides a thermosetting silicone composition that exhibits excellent adhesion and durability even when cured in a short time. The aforementioned problems are solved by a thermosetting silicone composition comprising (A) a polyorganosiloxane having at least two alkenyl groups at both ends of the molecular chain, (B) a resinous organopolysiloxane having at least two alkenyl groups at the ends of the molecular chain, (C) a polyorganosiloxane having at least two silicon atoms bonded to hydrogen atoms on the side chains of the molecular chain, and (D) a catalyst for the curing reaction.

Description

[Technical Field]

[0001] This invention relates to a thermosetting silicone composition. More specifically, this invention relates to a thermosetting silicone composition exhibiting high adhesion under short curing conditions. Furthermore, this invention also relates to a sealing material comprising the composition, and an optical semiconductor device sealed by the sealing material. [Background Technology]

[0002] Compared to organic compounds with epoxy groups, silicone compositions exhibit superior thermal and light stability, thus finding wide application across various industries. Cured silicone compositions, achieved through hydrosilylation, possess excellent heat resistance, cold resistance, and electrical insulation properties, making them widely used in electrical and electronic applications. Silicone compositions are particularly well-suited for bonding optoelectronic semiconductor devices such as optocouplers, LEDs (light-emitting diodes), and solid-state imaging elements.

[0003] For example, Patent Document 1 describes a curable organosilicon composition for sealing or potting electrical and electronic components, which comprises at least the following components: (A) an organopolysiloxane having at least two alkenyl groups in one molecule; (B) an organopolysiloxane having at least two silicon atoms bonded to hydrogen atoms in one molecule (the amount of silicon atoms bonded to hydrogen atoms in this component may be 0.5-10 moles relative to 1 mole of alkenyl groups in component (A); (C) a catalyst for the hydrogenation silylation reaction (catalytic amount); (D) an average particle size of 50 μm. The following are considered as well: approximately spherical silica micropowders of less than 1 μm in size {containing 200 or more parts by mass relative to the total of 100 parts by mass of components (A) and (B)}; and glass fibers of (E) having an average fiber length of less than 1000 μm and an average fiber diameter of less than 30 μm {containing 25 or more parts by mass relative to the total of 100 parts by mass of components (A) and (B)}, wherein the total content of components (D) and (E) is less than 900 parts by mass relative to the total of 100 parts by mass of components (A) and (B).

[0004] Furthermore, Patent Document 2 describes a silicone elastomer composition with customizable functional properties, comprising A) a viscous silicone fluid and B) a silicone elastomer, wherein the A) viscous silicone fluid comprises (1) a hydrosilylation reaction product and (2) a carrier fluid, wherein the (1) hydrosilylation reaction product is a hydrosilylation reaction product of (a) a first straight-chain organopolysiloxane and (b) a second straight-chain organopolysiloxane, wherein the (a) first straight-chain organopolysiloxane comprises (R 1 R 2 R 3 SiO 1 / 2 ) unit and (R 4 R5 SiO 2 / 2 ) unit (where at least one R 1 -R 5 If it is an alkenyl group, then R 1 -R 5 Each is independently a hydrocarbon group), wherein (a) the first straight-chain organopolysiloxane contains less than 1% by weight of T units and Q units, and the degree of polymerization of (a) the first straight-chain organopolysiloxane is 100-15000, and (b) the second straight-chain organopolysiloxane contains (R... 6 R 7 R 8 SiO 1 / 2 ) unit and (R 9 R 10 SiO 2 / 2 ) unit (where at least one R 6 -R 10 If R is a hydrogen atom, then 6 -R 10 (a) The second linear organopolysiloxane contains less than 1% by weight of T and Q units, and the degree of polymerization of the second linear organopolysiloxane is 4-1000. The carrier fluid is selected from organosilicon fluids, organic solvents, organic oils and combinations thereof. The hydrosilylation reaction product contains alkenyl or Si-H functional groups. The hydrosilylation reaction product is present in an amount of 3-30 parts by weight relative to 100 parts by weight of the viscous organosilicon fluid. The viscous organosilicon fluid exhibits increased vertical stress observed in the vertical direction when a constant increasing shear force is applied. The organosilicon elastomer is different from the hydrosilylation reaction product of (1).

[0005] Furthermore, Patent Document 3 discloses a fluorescent organosilicon composition characterized in that it is obtained by subjecting a polysiloxane (a) having an alkenyl and / or hydrosilyl group, a compound (b) having a hydrosilyl or alkenyl group capable of hydrosilanizing with component (a), and an organosilicon compound (a') having an alkenyl or hydrosilyl group in one molecule as needed to a hydrosilanizing reaction in the presence of a fluorescent substance.

[0006] Furthermore, Patent Document 4 describes a curable resin composition comprising (A) an organic acid having at least two polar groups within its molecule, (B) a polysiloxane composition, and (C) a hydrogenated silanization catalyst.

[0007] [Existing Technical Documents]

[0008] [Patent Documents]

[0009] Patent Document 1: Japanese Patent Application Publication No. 2018-119167

[0010] Patent Document 2: Japanese Patent Publication No. 2017-523283

[0011] Patent Document 3: Japanese Patent Application Publication No. 2017-160453

[0012] Patent Document 4: Japanese Patent Application Publication No. 2016-186061 [Summary of the Invention]

[0013] [The problem the invention aims to solve]

[0014] When using silicone compositions as sealing materials for optical semiconductor devices such as LEDs, high durability requires bonding to various materials, including metals and organic resins. Silicone products for this purpose are typically obtained through an addition reaction of a curable silicone composition upon heating.

[0015] However, typical silicone products obtained through addition reaction curing suffer from low adhesion and require long curing times. Furthermore, conventional silicone products obtained by curing curable silicone compositions in a short time do not achieve sufficient durability under high temperature and humidity conditions. Therefore, there is a problem that a long curing time is required for the curable silicone composition to obtain silicone products with sufficient durability.

[0016] The purpose of this invention is to provide a thermosetting silicone composition that, even when cured in a short time, exhibits excellent adhesion and durability under high temperature and high humidity conditions.

[0017] Another object of the present invention is to provide a sealing material comprising the thermosetting silicone composition of the present invention. Furthermore, yet another object of the present invention is to provide an optical semiconductor device sealed by the sealing material of the present invention.

[0018] [Methods used to solve problems]

[0019] To address the aforementioned problems, the inventors conducted in-depth research and unexpectedly discovered that by combining alkenyl-terminated linear organopolysiloxanes at both ends of the molecular chain, resinous organopolysiloxanes having at least two alkenyl groups at the ends of the molecular chain, and organohydrogen-based organosiloxanes having at least two silicon atoms bonded to hydrogen atoms on the side chains of the molecular chain, a thermosetting organosilicon composition capable of forming a cured product with sufficient durability even when cured in a short time can be provided, thus realizing the present invention.

[0020] Therefore, the present invention relates to a thermosetting silicone composition comprising:

[0021] (A) Alkenyl-terminated linear organopolysiloxanes at both ends of the molecular chain;

[0022] (B) A resinous organopolysiloxane having at least two alkenyl groups at the end of its molecular chain;

[0023] (C) an organohydrogen polysiloxane having at least two silicon atoms bonded to hydrogen atoms on the side chain of its molecular chain; and

[0024] (D) Catalyst for curing reaction.

[0025] Preferably, the organohydrogen polysiloxane of component (C) is linear.

[0026] (A) Preferably, the molecular chain of the component is end-capped with alkenyl groups, forming a linear organopolysiloxane.

[0027] Represented by the following structural formula: R 1 R 2 2SiO(R 2 2SiO) n SiR 1 R 2 2.

[0028] In the formula, R 1 It is an alkenyl group, R 2 Each is an independent monovalent hydrocarbon group other than an alkenyl group, and n is an integer from 5 to 1500.

[0029] Preferably, component (B) is a resinous organopolysiloxane having at least two alkenyl groups at the ends of its molecular chain, derived from RSiO. 1 / 2 The siloxane unit and RSiO are represented. 4 / 2 The siloxane unit is represented.

[0030] The present invention also relates to a sealing material comprising the thermosetting silicone composition of the present invention.

[0031] The present invention also relates to an optical semiconductor device sealed by the sealing material involved in the present invention.

[0032] [Invention Effects]

[0033] The thermosetting silicone composition according to the present invention, when cured by heating for a short time, such as 10 minutes, produces a cured product with high adhesion and durability under high humidity conditions.

Detailed Implementation Methods

[0034] [Thermosetting silicone composition]

[0035] The thermosetting silicone composition involved in this invention comprises:

[0036] (A) Alkenyl-terminated linear organopolysiloxanes at both ends of the molecular chain;

[0037] (B) A resinous organopolysiloxane having at least two alkenyl groups at the end of its molecular chain;

[0038] (C) an organohydrogen polysiloxane having at least two silicon atoms bonded to hydrogen atoms on the side chain of its molecular chain; and

[0039] (D) Catalyst for curing reaction.

[0040] The components of the thermosetting silicone composition of the present invention will now be described in detail.

[0041] (A) Alkenyl-terminated linear organopolysiloxanes at both ends of the molecular chain

[0042] (A) is a linear organopolysiloxane with alkenyl end caps at both ends of its molecular chain. (A) may include one linear organopolysiloxane with alkenyl end caps at both ends of its molecular chain, or may include a combination of two or more linear organopolysiloxanes with alkenyl end caps at both ends of their molecular chains.

[0043] (A) is a linear organopolysiloxane with alkenyl-terminated ends on both sides of its molecular chain, preferably an (A)-terminated)-)-)-)

[0044] From structural formula (I): R 1 R 2 2SiO(R 2 2SiO) n SiR 1 R 2 2

[0045] In equation (I), R 1 It is an alkenyl group, R 2 Each is an independent monovalent hydrocarbon group other than an alkenyl group, and n is an integer from 5 to 1500.

[0046] R, as in equation (I) above 1 Examples of alkenyl groups include vinyl, allyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, and dodecenyl alkenyl groups with 2 to 12 carbon atoms, preferably alkenyl groups with 2 to 6 carbon atoms, and particularly preferably vinyl.

[0047] R, as in equation (I) above 2Monovalent hydrocarbon groups other than alkenyl groups, for example, include: alkyl groups with 1-12 carbon atoms such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, neopentyl, hexyl, cyclohexyl, heptyl, octyl, nonyl, decyl, undecyl, and dodecyl; aryl groups with 6-20 carbon atoms such as phenyl, tolyl, xylyl, and naphthyl; aralkyl groups with 7-20 carbon atoms such as benzyl, phenethyl, and phenylpropyl; and groups in which the hydrogen atoms of these groups are partially or completely replaced by halogen atoms such as fluorine, chlorine, and bromine atoms, preferably alkyl groups with 1-6 carbon atoms, and particularly preferably methyl.

[0048] In the above formula (I), n is preferably 10 or more, more preferably 25 or more, even more preferably 50 or more, most preferably 100 or more, and particularly preferably 300 or more. Furthermore, in the above formula (I), n is preferably 1200 or less, more preferably 1000 or less, more preferably 800 or less, most preferably 750 or less, and particularly preferably 700 or less.

[0049] The amount of alkenyl groups in all silicon-bonded functional groups of component (A) is not particularly limited, but is, for example, 0.01 mol% or more, preferably 0.05 mol% or more, more preferably 0.1 mol% or more, and even more preferably 0.15 mol% or more relative to all silicon-bonded functional groups. Furthermore, the amount of alkenyl groups in all silicon-bonded functional groups of component (A) is, for example, 5 mol% or less, preferably 3 mol% or less, more preferably 1 mol% or less, and even more preferably 0.5 mol% or less. Additionally, the number of alkenyl groups can be determined by analytical methods such as Fourier transform infrared spectrophotometry (FT-IR), nuclear magnetic resonance (NMR), or titration methods.

[0050] A method for quantifying the amount of alkenyl groups in each component by titration is described. The alkenyl content in organopolysiloxane components can be quantified with high precision by a titration method commonly known as the Wigges method. The principle is as follows. First, the alkenyl groups in the organopolysiloxane raw material are subjected to an addition reaction with iodine monochloride as shown in formula (1). Next, excess iodine monochloride is reacted with potassium iodide to release iodine through the reaction shown in formula (2). The released iodine is then titrated with sodium thiosulfate solution.

[0051] Equation (1) CH2=CH-+2ICl→CH2I-CHCl-+ICl (excess)

[0052] Equation (2) ICl + KI → I2 + KCl

[0053] The amount of alkenyl groups in the component can be quantified by the difference between the amount of sodium thiosulfate required for titration and the titration amount of a separately prepared blank solution.

[0054] The amount of alkenyl-terminated linear organopolysiloxane at both ends of the molecular chain of component (A) is not particularly limited, but it is preferably 20% by mass or more, more preferably 30% by mass or more, further preferably 40% by mass or more, most preferably 50% by mass or more, and particularly preferably 60% by mass or more, based on the total mass of all organopolysiloxane components contained in the thermosetting silicone composition according to the present invention. Furthermore, the alkenyl-terminated linear organopolysiloxane at both ends of the molecular chain of component (A) is, for example, included in an amount of 90% by mass or less, preferably 80% by mass or less, more preferably 75% by mass or less, and further preferably 70% by mass or less, based on the total mass of all organopolysiloxane components.

[0055] (B) Resin-like organopolysiloxanes having at least two alkenyl groups at the ends of their molecular chains

[0056] (B) is a resinous organopolysiloxane having at least two alkenyl groups at the end of its molecular chain. In this specification, a resinous organopolysiloxane refers to an organopolysiloxane having a branched or network structure in its molecular structure. (B) may include one resinous organopolysiloxane having at least two alkenyl groups at the end of its molecular chain, or may combine two or more resinous organopolysiloxanes having at least two alkenyl groups at the end of their molecular chains.

[0057] In one embodiment, the resinous organopolysiloxane of component (B) contains at least one component of RSiO in its molecular structure. 4 / 2 The siloxane unit (Q unit) is represented. (B) The resinous organopolysiloxane of component (Q) may or may not contain at least one RSiO2 unit in its molecular structure. 3 / 2 The term refers to the siloxane unit (T unit), but is preferably not included. In a particular embodiment of the invention, the resinous organopolysiloxane of component (B) may be composed of RSiO 1 / 2 The siloxane unit (M unit) and RSiO2 are represented. 4 / 2 The MQ resin is composed of siloxane units (Q units).

[0058] (B) The resinous organopolysiloxane of component (B) is preferred.

[0059] From the average unit equation (II): (R) 3 3SiO 1 / 2 ) a (R 3 2SiO 2 / 2 ) b (R 3 SiO 3 / 2 ) c (SiO 4 / 2 ) d (XO1 / 2 ) e

[0060] In equation (II), R 3 Each is an independent monovalent hydrocarbon group, wherein R 3 At least two of them are alkenyl groups, X is a hydrogen atom or an alkyl group, 0≤a<1, 0≤b<1, 0≤c<0.9, 0≤d<0.9, 0≤e≤0.2, a+b+c+d=1.0, and c+d>0.

[0061] In the above formula (II) for component (B), as R 3 Monovalent hydrocarbon groups can be listed as follows: alkyl groups with 1-12 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, neopentyl, hexyl, cyclohexyl, heptyl, octyl, nonyl, decyl, undecyl, and dodecyl; aryl groups with 6-20 carbon atoms, such as phenyl, tolyl, xylyl, and naphthyl; aralkyl groups with 7-20 carbon atoms, such as benzyl, phenethyl, and phenylpropyl; alkenyl groups with 2-12 carbon atoms, such as vinyl, allyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, and dodecenyl; and groups in which the hydrogen atoms of these groups are partially or completely replaced by halogen atoms such as fluorine, chlorine, and bromine. R 3 Preferably, the alkyl group having 1-6 carbon atoms, especially methyl, and the alkenyl group having 2-6 carbon atoms, especially vinyl.

[0062] In formula (II) of component (B), X is a hydrogen atom or an alkyl group. The alkyl group of X is preferably an alkyl group having 1 to 3 carbon atoms, specifically methyl, ethyl and propyl can be examples.

[0063] In formula (II) above for component (B), a is preferably in the range of 0.1 ≤ a ≤ 0.8, more preferably in the range of 0.2 ≤ a ≤ 0.7, and even more preferably in the range of 0.3 ≤ a ≤ 0.6. In formula (II) above for component (B), b is preferably in the range of 0 ≤ b ≤ 0.4, more preferably in the range of 0 ≤ b ≤ 0.2, and particularly in the range of 0 ≤ b ≤ 0.1. In formula (II) above for component (B), c is preferably in the range of 0 ≤ c ≤ 0.4, more preferably in the range of 0 ≤ c ≤ 0.2, and particularly in the range of 0 ≤ c ≤ 0.1. In formula (II) above for component (B), d is preferably in the range of 0.1 ≤ d ≤ 0.8, more preferably in the range of 0.2 ≤ d ≤ 0.7, and even more preferably in the range of 0.3 ≤ d ≤ 0.6.

[0064] (B) The alkenyl-containing resinous organopolysiloxane contains an alkenyl group at the end of its molecular chain. That is, (B) the alkenyl-containing resinous organopolysiloxane is formed by R... 3 3SiO 1 / 2The indicated siloxane unit (M unit) has an alkenyl group, while the D unit and / or T unit does not contain an alkenyl group.

[0065] (B) The molecular weight of the organopolysiloxane in component (B) is not particularly limited; for example, the weight-average molecular weight (Mw) converted to standard polystyrene can be in the range of 1,000 to 100,000. Furthermore, the weight-average molecular weight (Mw) can be determined, for example, by GPC.

[0066] (B) The alkenyl-containing resinous organopolysiloxane represented by formula (II) above has at least two alkenyl groups in each molecule. The amount of alkenyl groups in all silicon-bonded functional groups of (B) is not particularly limited, but is, for example, 1 mol% or more, preferably 2 mol% or more, more preferably 4 mol% or more, and even more preferably 6 mol% or more, relative to the total amount of silicon-bonded functional groups. Furthermore, the amount of alkenyl groups in all silicon-bonded functional groups of (A) is, for example, 20 mol% or less, preferably 15 mol% or less, more preferably 12 mol% or less, and even more preferably 10 mol% or less. Additionally, the number of alkenyl groups can be determined by analytical methods such as Fourier transform infrared spectrophotometry (FT-IR), nuclear magnetic resonance (NMR), or the titration method described above.

[0067] The amount of the alkenyl-containing resinous organopolysiloxane in component (B) is not particularly limited. Based on the total mass of all organopolysiloxane components contained in the thermosetting silicone composition according to the present invention, it is preferably 5% by mass or more, more preferably 10% by mass or more, further preferably 15% by mass or more, most preferably 20% by mass or more, and particularly preferably 25% by mass or more. Furthermore, the resinous alkenyl-containing organopolysiloxane in component (B) is, for example, included in an amount of 80% by mass or less, more preferably 70% by mass or less, and further preferably 60% by mass or less, based on the total mass of all organopolysiloxane components.

[0068] (C) Organohydrogen polysiloxanes having at least two silicon atoms bonded to hydrogen atoms on the side chains of their molecular chains.

[0069] The thermosetting organosilicon composition of the present invention comprises component (C), namely, an organohydrogen polysiloxane having at least two silicon atoms bonded to hydrogen atoms in one molecule of the molecular chain side chain, as a crosslinking agent. Component (C) may be a single organohydrogen polysiloxane or a combination of two or more organohydrogen polysiloxanes.

[0070] Examples of molecular structures for component (C), namely organohydrogen polysiloxane, include: linear, partially branched linear, branched, cyclic, and three-dimensional network structures, preferably linear or branched structures, and more preferably linear structures. Component (C) may use an organohydrogen polysiloxane with one structure, or a combination of two or more organohydrogen polysiloxane structures.

[0071] The hydrogen atoms bonded to the silicon atoms in component (C) are hydrogen atoms bonded to silicon atoms other than the terminal silicon atoms of the organohydrogen polysiloxane. Examples of silicon atom bonding functional groups other than hydrogen atoms in component (C) include monovalent hydrocarbon groups, specifically: alkyl groups with 1-12 carbon atoms such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, neopentyl, hexyl, cyclohexyl, heptyl, octyl, nonyl, decyl, undecyl, and dodecyl; aryl groups with 6-20 carbon atoms such as phenyl, tolyl, xylyl, and naphthyl; aralkyl groups with 7-20 carbon atoms such as benzyl, phenethyl, and phenylpropyl; and groups in which the hydrogen atoms of these groups are partially or completely replaced by halogen atoms such as fluorine, chlorine, and bromine atoms. Furthermore, without prejudice to the purpose of this invention, the silicon atoms in component (C) may have a small amount of alkoxy groups such as hydroxyl, methoxy, and ethoxy groups.

[0072] In one embodiment, the organohydrogen polysiloxane of component (C) is preferably linear.

[0073] From structural formula (III): R 4 3SiO(R 5 2SiO) m SiR 4 3

[0074] In equation (III), R 4 Each is an independent monovalent hydrocarbon group, R 5 It is a monovalent hydrocarbon group or hydrogen atom, wherein one mole contains at least two R groups. 5 For each hydrogen atom, m is an integer between 3 and 200.

[0075] In the above formula (III) for component (C), as R 4 and R 5The monovalent hydrocarbon group can be exemplified by: alkyl groups with 1-12 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, neopentyl, hexyl, cyclohexyl, heptyl, octyl, nonyl, decyl, undecyl, and dodecyl; aryl groups with 6-20 carbon atoms, such as phenyl, tolyl, xylyl, and naphthyl; aralkyl groups with 7-20 carbon atoms, such as benzyl, phenethyl, and phenylpropyl; alkenyl groups with 2-12 carbon atoms, such as vinyl, allyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, and dodecenyl; and groups in which the hydrogen atoms of these groups are partially or completely replaced by halogen atoms such as fluorine, chlorine, and bromine atoms, preferably alkyl groups with 1-6 carbon atoms, more preferably methyl.

[0076] In formula (III) above, m is preferably 5 or more, more preferably 10 or more, even more preferably 20 or more, most preferably 30 or more, and particularly preferably 40 or more. Furthermore, in formula (III) above, m is preferably 300 or less, more preferably 200 or less, more preferably 150 or less, most preferably 100 or less, and particularly preferably 75 or less.

[0077] The amount of organohydrogen polysiloxane in component (C) is not particularly limited. Based on the total mass of all organopolysiloxane components contained in the thermosetting silicone composition according to the present invention, it is preferably 0.5% by mass or more, more preferably 1% by mass or more, further preferably 2% by mass or more, most preferably 3% by mass or more, and particularly preferably 4% by mass or more. Furthermore, the organopolysiloxane in component (C) is, for example, based on the total mass of all organopolysiloxane components, included in an amount of 20% by mass or less, preferably 15% by mass or less, more preferably 10% by mass or less, and further preferably 7% by mass or less.

[0078] Furthermore, in other embodiments, the content of the organohydrogen polysiloxane in component (C) may be, for example, 1.0-3.0 moles of silicon-bonded hydrogen atoms, preferably 1.5-2.5 moles, relative to 1 mole of silicon-bonded alkenyl groups in the thermosetting organosilicon composition. Additionally, the content of silicon-bonded hydrogen atoms in component (C) can be determined by analysis, for example, using Fourier transform infrared spectrophotometry (FT-IR) or nuclear magnetic resonance (NMR).

[0079] In one embodiment of the present invention, based on the total number of silicon-bonded functional groups in the entire composition, the amount of silicon-bonded hydrogen atoms in the overall composition is not particularly limited, but is preferably 0.54 mol% or more, more preferably 0.82 mol% or more. Furthermore, in other embodiments of the present invention, based on the total amount of silicon-bonded functional groups contained in the organopolysiloxane component of the thermosetting organosilicon composition of the present invention, the amount of silicon-bonded hydrogen atoms is not particularly limited, but is preferably 0.54 mol% or more, more preferably 0.82 mol% or more.

[0080] In addition to comprising component (C), namely an organohydrogen polysiloxane having at least two silicon atoms bonded to hydrogen atoms on the side chain of the molecular chain, the thermosetting organosilicon composition involved in this invention may also include an organohydrogen polysiloxane having silicon atoms bonded to hydrogen atoms at the end of the molecular chain as a crosslinking agent.

[0081] Examples of organohydrogen polysiloxanes with silicon atoms bonded to hydrogen atoms at the ends of their molecular chains include linear, partially branched linear, branched, cyclic, and three-dimensional network structures. Linear or branched structures are preferred, and linear structures are even more preferred. Such organohydrogen polysiloxanes with silicon atoms bonded to hydrogen atoms at the ends of their molecular chains can be used in isolation or in combination of two or more types.

[0082] The linear organohydrogen polysiloxane with silicon atoms bonded to hydrogen atoms at the ends of the molecular chain is preferably an organohydrogen polysiloxane with hydrogenated silyl groups at both ends of the molecular chain. Examples include: dimethylhydrosiloxy-terminated dimethyl polysiloxane and dimethylhydrosiloxy-terminated dimethylsiloxane-methylphenylsiloxane copolymer.

[0083] Preferably, the amount of hydrogenated silyl-terminated organohydrogen polysiloxane is not particularly limited, but based on the total mass of all organopolysiloxane components contained in the thermosetting organosilicon composition involved in the present invention, the amount is 10% by mass or less, preferably 8.0% by mass or less, more preferably 4.0% by mass or less, and even more preferably 2.0% by mass or less.

[0084] (D) Catalyst for curing reaction

[0085] The thermosetting silicone composition of the present invention comprises a curing reaction catalyst for curing the organopolysiloxane component as a (D) component. The thermosetting silicone composition of the present invention may contain one (D) curing reaction catalyst or two or more (D) curing reaction catalysts.

[0086] The curing catalyst of component (D) is a catalyst used to promote the curing of an addition reaction-curable organosilicon composition based on hydrosilylation. Examples of such components (D) include: platinum-based catalysts such as chloroplatinic acid, alcoholic solutions of chloroplatinic acid, platinum-olefin complexes, platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complexes, and platinum-supported powders; palladium-based catalysts such as tetra(triphenylphosphine)palladium, palladium black, and mixtures with triphenylphosphine; and rhodium-based catalysts, with platinum-based catalysts being particularly preferred.

[0087] (D) The amount of catalyst used for curing is the amount of catalyst required for curing the thermosetting organosilicon composition of the present invention, and there is no particular limitation. For example, when using a platinum catalyst, the amount of platinum metal contained in the platinum catalyst is preferably in the range of 0.01-1000 ppm by weight in the organosilicon composition, and particularly preferably in the range of 0.1-500 ppm.

[0088] The thermosetting silicone composition of the present invention can be formulated with any ingredients without prejudice to the purpose of the invention. Examples of such arbitrary ingredients include, for instance, adhesion promoters, silane coupling agents, reaction inhibitors, acetylene compounds, organophosphorus compounds, vinylsiloxane compounds, ultraviolet absorbers, sensitizers, light stabilizers, antioxidants, ultraviolet absorbers, defoamers, leveling agents, inorganic fillers, surfactants, tackifiers, release agents, metallic soaps, heat resistant agents, cold resistant agents, thermally conductive fillers, flame retardants, thixotropic agents, phosphors, solvents, etc.

[0089] Adhesion accelerator

[0090] The thermosetting silicone composition of the present invention may contain an adhesion promoter. The adhesion promoter is preferably an organosilicon compound functionalized with epoxy or alkoxy groups. Examples of adhesion promoters include: trialkoxysilyloxy (e.g., trimethoxysilyloxy and triethoxysilyloxy) or trialkoxysilylalkyl (e.g., trimethoxysilyl, triethoxysilylethyl), organosilanes having hydrogenated silyl or alkenyl (e.g., vinyl, allyl), or linear, branched, or cyclic organosilicon oligomers having about 4-20 silicon atoms; organosilanes having trialkoxysilyloxy or trialkoxysilylalkyl and methacryloyloxyalkyl (e.g., 3-methacryloyloxypropyl). Organosiloxane oligomers with approximately 4-20 silicon atoms, either linear, branched, or cyclic; organosilanes having a trialkoxysilyl or trialkoxysilylalkyl and epoxy-bonded alkyl groups (e.g., 3-epoxypropoxypropyl, 4-epoxypropoxybutyl, 2-(3,4-epoxycyclohexyl)ethyl, 3-(3,4-epoxycyclohexyl)propyl) or linear, branched, or cyclic organosiloxane oligomers with approximately 4-20 silicon atoms; reactants of aminoalkyltrialkoxysilanes and epoxy-bonded alkyltrialkoxysilanes; epoxy-containing polyethyl silicate. Specifically, examples include: vinyltrimethoxysilane, allyltrimethoxysilane, allyltriethoxysilane, hydrogentriethoxysilane, 3-epoxypropoxypropyltrimethoxysilane, 3-epoxypropoxypropyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropyltriethoxysilane, diethoxymethyl(3-(epoxycyclohexyl)methyl) The composition contains tri(3-(3-trimethoxypropyl)propyl)silane, a reaction product of 3-epoxypropoxypropyltrimethoxysilane and 3-aminopropyltriethoxysilane, a condensation reaction product of hydroxyl-terminated methylvinylsiloxane oligomers and 3-epoxypropoxypropyltrimethoxysilane, a condensation reaction product of hydroxyl-terminated methylvinylsiloxane oligomers and 3-methacryloyloxypropyltriethoxysilane, and tris(3-trimethoxysilylpropyl)isocyanurate. The adhesion promoter in this composition can be a mixture of two or more of the above-mentioned reactants, preferably a mixture of a condensation reaction product of hydroxyl-terminated methylvinylsiloxane oligomers and 3-methacryloyloxypropyltriethoxysilane and diethoxymethyl(3-(epoxyethoxypropyl)propyl)silane. In this composition, the ratio of the reactants in the adhesive accelerator mixture can be any ratio. For example, the ratio of the two reactants in the adhesive accelerator mixture can be 1:10 (mass) to 10:1 (mass), and more specifically, it can be 2:1 (mass), 1:1 (mass), or 1:2 (mass).In this composition, the content of the adhesion promoter is not limited, but is preferably in the range of 0.1-20 parts by weight relative to the total 100 parts by weight of the organopolysiloxane component, and more preferably in the range of 0.2-10 parts by weight.

[0091] Silane coupling agents

[0092] The thermosetting organosilicon composition of the present invention may contain a silane coupling agent. Specific examples of silane coupling agents include epoxy-alkoxysilane compounds such as γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane; mercaptoalkoxysilane compounds such as γ-mercaptopropyltrimethoxysilane and γ-mercaptopropyltriethoxysilane; ureopropyltriethoxysilane compounds such as γ-ureopropyltrimethoxysilane, γ-ureopropyltrimethoxysilane, and γ-(2-ureoethyl)aminopropyltrimethoxysilane; and γ-isocyanate propylene glycol. The silane coupling agent includes isocyanate-containing alkoxysilane compounds such as γ-isocyanate propyltrimethoxysilane, γ-isocyanate propylmethyldimethoxysilane, γ-isocyanate propylmethyldiethoxysilane, γ-isocyanate propylethyldimethoxysilane, γ-isocyanate propylethyldiethoxysilane, and γ-isocyanate propyltrichlorosilane; and aminoalkoxysilane compounds such as γ-(2-aminoethyl)aminopropylmethyldimethoxysilane, γ-(2-aminoethyl)aminopropyltrimethoxysilane, and γ-aminopropyltrimethoxysilane. The amount of silane coupling agent is not particularly limited, but based on the total mass of all organopolysiloxane components contained in the thermosetting organosilicon composition involved in this invention, it is preferably 2.0% by mass or less.

[0093] Response inhibitors

[0094] The thermosetting silicone composition of the present invention may contain a reaction inhibitor for inhibiting the curing reaction. The reaction inhibitor is preferably a compound functionalized with an olefinic or alkylene group. Examples of reaction inhibitors include: alkynyl alcohols such as 1-ethynylcyclohexane-1-ol, 2-methyl-3-butyn-2-ol, 3,5-dimethyl-1-hexyn-3-ol, and 2-phenyl-3-butyn-2-ol; enynyne compounds such as 3-methyl-3-penten-1-yne and 3,5-dimethyl-3-hexen-1-yne; alkynoxysilanes such as 1,1-dimethylpropynyloxytrimethylsilane (methyl-tris(3-methyl-1-butyn-3-oxy)silane), bis(1,1-dimethylpropynoxy)dimethylsilane, and bis(1,1-dimethylpropynoxy)methylvinylsilane; and other benzotriazoles. In this composition, the content of the reaction inhibitor is not limited, but is preferably in the range of 0.001-5 parts by mass relative to the total 100 parts by mass of the organopolysiloxane component, and more preferably in the range of 0.01-1 parts by mass.

[0095] Heat resistant agent

[0096] The thermosetting organosilicon composition of the present invention may contain a heat-resistant agent. There are no particular limitations on the heat-resistant agent; examples include iron oxide (iron oxide), cerium oxide, cerium dimethylsiloxane, cerium fatty acid salts, cerium hydroxide, or zirconium compounds. The heat-resistant agent is preferably a cerium-containing organopolysiloxane. In this composition, the content of the heat-resistant agent is not limited, but is preferably in the range of 0.1-20 parts by weight relative to 100 parts by weight of the total organopolysiloxane component, and more preferably in the range of 0.2-10 parts by weight.

[0097] The thermosetting silicone composition of the present invention can be cured in a short time, for example, by heating for less than 10 minutes. The heating temperature for curing the thermosetting silicone composition of the present invention is preferably above 100°C, more preferably 150°C-200°C. Even when cured in a short time, the cured product of the thermosetting silicone composition of the present invention exhibits excellent adhesion and durability under high temperature and high humidity conditions.

[0098] The thermosetting silicone composition of the present invention can be prepared by mixing the various components. The mixing method can be any method known in the art and is not particularly limited; generally, a homogeneous mixture is formed by simple stirring. Alternatively, a mixing apparatus can be used. Such a mixing apparatus is not particularly limited, and examples include single-shaft or bi-shaft continuous mixers, two-roll mills, Ross mixers, Hobart mixers, dental mixers, planetary mixers, kneading mixers, Henschel mixers, etc.

[0099] [Sealing material]

[0100] This invention also relates to a sealing material comprising the thermosetting silicone composition of this invention. The sealing material of this invention is preferably a sealing material for optical semiconductors. The shape of the sealing material of this invention is not particularly limited, but it is preferably in the form of a film or sheet. Therefore, this invention also relates to a film obtained by curing the thermosetting silicone composition of this invention. The film of this invention is preferably used as a thin-film sealing material for sealing semiconductor elements. The semiconductor sealed by the sealing material or film of this invention is not particularly limited; examples include semiconductors such as SiC and GaN, or optical semiconductors such as light-emitting diodes.

[0101] As a method for forming the thermosetting silicone composition of the present invention into a film or sheet, conventionally known methods can be used, such as: extruding into a film using an extruder equipped with a specific die, forming a uniform film by clamping it between organic resin films such as polyolefin films and polyester films using calendering rollers, or forming into a film using a press set at 40°C or below. Alternatively, continuous forming can be achieved by laminating between organic resin films using calendering rollers. The thus formed film-shaped sealing material can be cut from the long roll into the desired shape using a cutter or a punching machine for use.

[0102] The film thickness of the thin film or sheet-like sealing material of the present invention is not particularly limited, but is preferably in the range of 1μm-10mm or 5μm-5mm.

[0103] The sealing material according to the present invention, due to containing the thermosetting silicone composition of the present invention, exhibits excellent adhesion and durability even under high temperature and high humidity conditions, thus enabling the provision of highly reliable semiconductor devices.

[0104] [Optical Semiconductor Devices]

[0105] The optical semiconductor device of the present invention is an optical semiconductor element sealed by the sealing material of the present invention described above. In other words, the optical semiconductor element is sealed, encapsulated, or bonded by a sealing material comprising the thermosetting silicone composition of the present invention described above. Examples of such optical semiconductor elements include: light-emitting diodes (LEDs), semiconductor lasers, photodiodes, phototransistors, solid-state cameras, light-emitting and light-receiving elements for optocouplers, and light-emitting diodes (LEDs) are particularly preferred.

[0106] Light-emitting diodes (LEDs) emit light from the top, bottom, left, and right sides of a light-emitting semiconductor element. Therefore, the components constituting an LED are preferably made of materials that absorb light, but rather of materials with high light transmittance or high reflectivity. Consequently, the substrate on which the light-emitting semiconductor element is mounted is also preferably made of materials with high light transmittance or high reflectivity. Examples of substrates for mounting such light-emitting semiconductor elements include: conductive metals such as silver, gold, and copper; weakly conductive metals such as aluminum and nickel; thermoplastic resins mixed with white pigments such as PPA and LCP; thermosetting resins containing white pigments such as epoxy resin, BT resin, polyimide resin, and silicone resin; and ceramics such as alumina and aluminum nitride.

[0107] The optical semiconductor device of the present invention is sealed with the sealing material of the present invention, which has excellent adhesion and durability even under high temperature and high humidity conditions, thus ensuring high reliability.

[0108]

Example

[0109] The thermosetting silicone compositions of the present invention will be described in detail through the following examples and comparative examples.

[0110] In the following examples and comparative examples, the raw material components shown below were used. In the following text, Me represents methyl and Vi represents vinyl. Additionally, in the following text, epoxy and / or alkoxy-functionalized organosilicon is a condensation product of a hydroxyl-terminated methyl vinyl siloxane oligomer with 3-epoxypropoxypropyltrimethoxysilane and a 1:1 (by mass) mixture of diethoxymethyl(3-(epoxyethoxymethylmethoxy)propyl)silane.

[0111] (Example 1)

[0112] Me2ViSiO(Me2SiO) 550 SiMe2Vi: 65% by mass

[0113] (Me2ViSiO 1 / 2 ) 11 (Me3SiO 1 / 2 ) 34 (SiO 4 / 2 ) 55 30% by mass

[0114] Me3SiO (MeHSiO) 50 SiMe3: 5% by mass

[0115] Platinum (Pt) catalyst compound: 0.005 parts by mass per 100 parts by mass relative to the above-mentioned organopolysiloxane component.

[0116] Methyl-tris(3-methyl-1-butyn-3-oxo)silane: 0.05 parts by weight per 100 parts by weight relative to the above-mentioned organopolysiloxane components.

[0117] Epoxy and / or alkoxy functionalized organosilicon: 0.5 parts by weight per 100 parts by weight relative to the above organopolysiloxane components.

[0118] (Example 2)

[0119] Me2ViSiO(Me2SiO) 550 SiMe2Vi: 65% by mass

[0120] (Me2ViSiO 1 / 2 )6(Me3SiO 1 / 2 ) 36 (SiO 4 / 2 ) 58 30% by mass

[0121] Me3SiO (MeHSiO) 50 SiMe3: 5% by mass

[0122] Platinum (Pt) catalyst compound: 0.005 parts by mass per 100 parts by mass relative to the above-mentioned organopolysiloxane component.

[0123] Methyl-tris(3-methyl-1-butyn-3-oxo)silane: 0.05 parts by weight per 100 parts by weight relative to the above-mentioned organopolysiloxane components.

[0124] Epoxy and / or alkoxy functionalized organosilicon: 0.5 parts by weight per 100 parts by weight relative to the above organopolysiloxane components.

[0125] (Example 3)

[0126] Me2ViSiO(Me2SiO) 550 SiMe2Vi: 65% by mass

[0127] (Me2ViSiO 1 / 2 ) 11 (Me3SiO 1 / 2 ) 34 (SiO 4 / 2 ) 55 30% by mass

[0128] Me3SiO (MeHSiO) 50 SiMe3: 5% by mass

[0129] Platinum (Pt) catalyst compound: 0.005 parts by mass per 100 parts by mass relative to the above-mentioned organopolysiloxane component.

[0130] Methyl-tris(3-methyl-1-butyn-3-oxo)silane: 0.05 parts by weight per 100 parts by weight relative to the above-mentioned organopolysiloxane components.

[0131] Epoxy and / or alkoxy functionalized organosilicon: 0.5 parts by weight per 100 parts by weight relative to the above organopolysiloxane components.

[0132] Cerium-containing organopolysiloxane: 0.5 parts by weight per 100 parts by weight of the above-mentioned organopolysiloxane components.

[0133] (Comparative Example 1)

[0134] Me2ViSiO(Me2SiO) 550 SiMe2Vi: 99.5% by mass

[0135] Me3SiO (MeHSiO) 50 SiMe3: 0.5% by mass

[0136] Platinum (Pt) catalyst compound: 0.005 parts by mass per 100 parts by mass relative to the above-mentioned organopolysiloxane component.

[0137] 3,5-Dimethyl-1-hexenyl-3-ol: 0.05 parts by weight per 100 parts by weight relative to the above-mentioned organopolysiloxane components.

[0138] Epoxy and / or alkoxy functionalized organosilicon: 0.5 parts by weight per 100 parts by weight relative to the above organopolysiloxane components.

[0139] (Comparative Example 2)

[0140] Me2ViSiO(Me2SiO) 550 SiMe2Vi: 99.5% by mass

[0141] (Me2HSiO 1 / 2 ) 62.5 (SiO 4 / 2 ) 37.5 0.5% by mass

[0142] Platinum (Pt) catalyst compound: 0.005 parts by mass per 100 parts by mass relative to the above-mentioned organopolysiloxane component.

[0143] 3,5-Dimethyl-1-hexenyl-3-ol: 0.05 parts by weight per 100 parts by weight relative to the above-mentioned organopolysiloxane components.

[0144] Epoxy or alkoxy functionalized organosilicon: 0.5 parts by weight per 100 parts by weight of the above-mentioned organopolysiloxane components.

[0145] Adhesion test

[0146] 0.5 g of the curable silicone compositions of Examples 1-3 and Comparative Examples 1 and 2 were placed on a glass substrate and heated at 200°C for 10 minutes to obtain cured products. The cured products were then kept at 85°C and 85% humidity for 24 hours to check for any delamination between the glass substrate and the cured silicone. The cured products obtained from the curable silicone compositions of Examples 1-3 exhibited cohesive failure at the interface with the substrate, while the cured products obtained from the curable silicone compositions of Comparative Examples 1 and 2 showed interfacial delamination between the substrate and the material. Therefore, it can be confirmed that the thermosetting silicone compositions of the present invention exhibit excellent adhesion and durability even under high temperature and high humidity conditions.

[0147] [Industry Applicability]

[0148] The thermosetting silicone composition of the present invention can be used as a sealing material, coating agent, or adhesive for optical semiconductor elements such as light-emitting diodes (LEDs), semiconductor lasers, photodiodes, phototransistors, solid-state cameras, and light emitters and receivers for optical couplers. Furthermore, the optical semiconductor device of the present invention can be used as an optical device, optical equipment, lighting equipment, or other optical semiconductor device.

Claims

1. A thermosetting transparent silicone composition comprising: (A) linear organopolysiloxane capped at both molecular chain terminals with alkenyl groups, represented by the following structural formula: R 1 R 2 2SiO(R 2 2SiO) n SiR 1 R 2 2 In the formula, R 1 It is an alkenyl group, R 2 Each is independently a C1-12 alkyl group, and n is an integer from 5 to 1500; (B) A resinous organopolysiloxane having at least two alkenyl groups at the end of the molecular chain, wherein the alkenyl group accounts for more than 6 mol% of the total silicon atom bonded functional groups relative to the total amount of silicon atom bonded functional groups in (B). (C) An organohydrogen polysiloxane having at least two silicon atoms bonded to hydrogen atoms on the side chains of its molecular chain, represented by the following structural formula: R 4 3SiO(R 5 2SiO) m SiR 4 3 In the formula, R 4 Each independently of C1-12 alkyl, R 5 It is a C1-12 alkyl or hydrogen atom, and has at least two R atoms. 5 It is a hydrogen atom, and m is an integer between 3 and 200; (D) Catalyst for the curing reaction; and (E) Organosilicon compounds functionalized with epoxy or alkoxy groups, Based on the total mass of all organopolysiloxane components, component (A) comprises more than 60% by mass. Relative to 1 mole of silicon-bonded alkenyl groups in the composition, the content of organohydrogen polysiloxane in component (C) is 1.0-3.0 moles of silicon-hydrogen atoms, and The composition further includes methyl-tris(3-methyl-1-butyn-3-oxo)silane as a reaction inhibitor.

2. The thermosetting transparent silicone composition according to claim 1, wherein, (C) The organohydrogen polysiloxane of component (C) is linear.

3. The thermosetting transparent silicone composition according to any one of claims 1-2, wherein, (B) A resinous organopolysiloxane having at least two alkenyl groups at the ends of its molecular chain, derived from RSiO 1 / 2 The siloxane unit and RSiO are represented. 4 / 2 The siloxane unit is represented.

4. A sealing material comprising a thermosetting transparent silicone composition according to any one of claims 1-3.

5. A photonic semiconductor device, characterized in that, It is sealed by the sealing material as described in claim 4.