Thermosetting silicone composition

Abstract

To provide a thermosetting silicone composition which has excellent adhesiveness and durability even when cured in a short time.SOLUTION: The thermosetting silicone composition contains (A) a polyorganosiloxane having at least two alkenyl groups at both terminals of the molecular chain, (B) a resinous organopolysiloxane having at least two alkenyl groups at a terminal of the molecular chain, (C) a polyorganosiloxane having at least two silicon atom-bonded hydrogen atoms in side chains of the molecular chain, and (D) a catalyst for curing reaction.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a thermosetting silicone composition. More specifically, the present invention relates to a thermosetting silicone composition that exhibits high adhesiveness under short-time curing conditions. The present invention also relates to a sealing material containing the composition and an optical semiconductor device sealed with the sealing material.

Background Art

[0002] Silicone compositions are used in a wide range of industrial fields because they have excellent thermal and light stability compared to organic compounds having organic functional groups such as epoxy groups. Curable silicone compositions that cure by a hydrosilylation reaction are widely used in electrical and electronic applications because they have excellent heat resistance, cold resistance, electrical insulation, etc. In particular, silicone compositions are used for adhering optical semiconductor devices such as photocouplers, LEDs (light-emitting diodes), and solid-state imaging devices.

[0003] For example, Patent Document 1 discloses (A) an organopolysiloxane having at least two alkenyl groups in one molecule, (B) an organopolysiloxane having at least two silicon atom-bonded hydrogen atoms in one molecule {an amount such that the silicon atom-bonded hydrogen atoms in this component are 0.5 to 10 moles per mole of the alkenyl group in the (A) component}, (C) a catalyst for hydrosilylation reaction (catalytic amount), (D) a substantially spherical silica fine powder having an average particle diameter of 50 μm or less {200 parts by mass or more with respect to a total of 100 parts by mass of the (A) component and the (B) component}, and (E) a glass fiber having an average fiber length of 1,000 μm or less and an average fiber diameter of 30 μm or less {25 parts by mass or more with respect to a total of 100 parts by mass of the (A) component and the (B) component}, and at least consisting of these, and the total content of the (D) component and the (E) component is 900 parts by mass or less with respect to a total of 100 parts by mass of the (A) component and the (B) component, and a curable silicone composition for sealing or potting of electrical and electronic parts is described.

[0004] Also, Patent Document 2 discloses a silicone elastomer composition having customizable sensory 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, and the (1) hydrosilylation reaction product is a hydrosilylation reaction product of (a) a first linear organopolysiloxane and (b) a second linear organopolysiloxane, and the (a) first linear organopolysiloxane comprises (R 1 R 2 R 3 SiO 1 / 2 ) units and (R 4 R 5 SiO 2 / 2 ) units (wherein each of R 1 ~R 5 is independently a hydrocarbon group as long as at least one of R 1 ~R 5 is an alkenyl group), the (a) first linear organopolysiloxane contains less than 1% by weight of T units and Q units, the degree of polymerization of the (a) first linear organopolysiloxane is 100 to 15,000, and the (b) second linear organopolysiloxane comprises (R 6 R 7 R 8 SiO 1 / 2 ) units and (R 9 R 10 SiO 2 / 2 ) units (wherein each of R 6 ~R 10 is independently a hydrocarbon group as long as at least one of R 6 ~R 10As long as it is a hydrogen atom, it independently contains a hydrocarbon group, a polyether group, a siloxane group, or a polyol group), the said (b) second linear organopolysiloxane contains less than 1% by weight of T units and Q units, the degree of polymerization of the said (b) second linear organopolysiloxane is 4 to 1,000, the said (2) carrier fluid is selected from silicone fluids, organic solvents, organic oils, and combinations thereof, the said (1) hydrosilylation reaction product contains an alkenyl group or an Si-H functional group, the said (1) hydrosilylation reaction product is present in an amount of 3 to 30 parts by weight per 100 parts by weight of the said A) viscous silicone fluid, the said A) viscous silicone fluid exhibits an increasing vertical stress observed in the vertical direction when a constantly increasing shear force is applied, and the said B) silicone elastomer is a silicone elastomer composition different from the said (1) hydrosilylation reaction product.

[0005] Also, Patent Document 3 describes a phosphor-containing silicone-based composition characterized by being obtained by subjecting a polysiloxane (a) having an alkenyl group and / or a hydrosilyl group, a compound (b) having a hydrosilyl group or an alkenyl group capable of undergoing a hydrosilylation reaction with the component (a), and optionally an organosilicon compound (a') having one alkenyl group or hydrosilyl group in one molecule to a hydrosilylation reaction in the presence of a phosphor.

[0006] Also, Patent Document 4 describes a curable resin composition comprising (A) an organic acid having at least two or more polar groups in the molecule, (B) a polysiloxane composition, and (C) a hydrosilylation catalyst.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Patent Document 3

[0008] When a silicone composition is used as a sealing material for an optical semiconductor device such as an LED, it is necessary to adhere to a plurality of materials such as metals and organic resins in order to achieve high durability. Silicone products used for this purpose are usually obtained by an addition reaction by heating a curable silicone composition.

[0009] However, typical silicone products obtained by curing by an addition reaction have problems such as low adhesiveness and the need for a long time for curing. In addition, silicone products obtained by curing a conventional curable silicone composition in a short time did not have sufficient durability under high temperature and high humidity conditions. Therefore, there was a problem that it was necessary to cure the curable silicone composition for a long time in order to obtain a silicone product having sufficient durability.

[0010] An object of the present invention is to provide a thermosetting silicone composition capable of exhibiting excellent adhesiveness and durability under high temperature and high humidity even when cured in a short time.

[0011] Another object of the present invention is to provide a sealing material containing the thermosetting silicone composition of the present invention. Still another object of the present invention is to provide an optical semiconductor device sealed with the sealing material of the present invention. [Means for Solving the Problems]

[0012] To solve the above problems, as a result of intensive studies, the present inventors have surprisingly found that, even when cured in a short time, a thermosetting silicone composition capable of forming a cured product having sufficient durability can be provided by combining a linear organopolysiloxane having alkenyl groups blocked at both ends of the molecular chain, a resinous organopolysiloxane having at least two alkenyl groups at the molecular chain ends, and an organohydrogenpolysiloxane having at least two silicon atom-bonded hydrogen atoms in the side chains of the molecular chain, and thus have reached the present invention.

[0013] Therefore, the present invention relates to (A) a linear organopolysiloxane having alkenyl groups blocked at both ends of the molecular chain and (B) a resinous organopolysiloxane having at least two alkenyl groups at the molecular chain ends and (C) an organohydrogenpolysiloxane having at least two silicon atom-bonded hydrogen atoms in the side chains of the molecular chain and (D) a catalyst for the curing reaction and relates to a thermosetting silicone composition containing the same.

[0014] It is preferable that the organohydrogenpolysiloxane as the component (C) is linear.

[0015] The linear organopolysiloxane having alkenyl groups blocked at both ends of the molecular chain as the component (A) is Structural formula: R 1 R 2 2SiO(R 2 2SiO) n SiR 1 R 2 2 (In the formula, R 1 is an alkenyl group, R 2 are each independently a monovalent hydrocarbon group other than an alkenyl group, and n is an integer of 5 to 1500) and is preferably represented by.

[0016] The resinous organopolysiloxane having at least two alkenyl groups at the molecular chain ends as the component (B) is RSiO 1 / 2The siloxane units represented by and RSiO 4 / 2 It is preferably composed of siloxane units represented by .

[0017] The present invention also relates to a sealing material containing the curable silicone composition according to the present invention.

[0018] The present invention also relates to an optical semiconductor device sealed with the sealing material according to the present invention.

Effects of the Invention

[0019] According to the thermosetting silicone composition of the present invention, it cures by heating for a short time, for example, heating for 10 minutes, and the obtained cured product has high adhesion properties and durability under high humidity conditions.

Modes for Carrying Out the Invention

[0020] [Thermosetting Silicone Composition] The thermosetting silicone composition according to the present invention is (A) A linear organopolysiloxane having alkenyl groups blocked at both ends of the molecular chain and (B) A resinous organopolysiloxane having at least two alkenyl groups at the molecular chain ends and (C) An organohydrogenpolysiloxane having at least two silicon atom-bonded hydrogen atoms in the side chains of the molecular chain and (D) A catalyst for the curing reaction It is a thermosetting silicone composition containing

[0021] Hereinafter, each component of the thermosetting silicone composition of the present invention will be described in detail.

[0022] (A) Linear Organopolysiloxane with Alkenyl Groups Blocked at Both Ends of the Molecular Chain Component (A) is a linear organopolysiloxane having alkenyl groups blocked at both ends of the molecular chain. Component (A) may contain one kind of linear organopolysiloxane having alkenyl groups blocked at both ends of the molecular chain, or may contain a combination of two or more kinds of linear organopolysiloxanes having alkenyl groups blocked at both ends of the molecular chain.

[0023] (A) component of the molecular chain both ends alkenyl group-blocked linear organopolysiloxane is preferably Structural formula (I): R 1 R 2 2SiO(R 2 2SiO) n SiR 1 R 2 2 represented by, where, in formula (I), R 1 is an alkenyl group, and R 2 are each independently a monovalent hydrocarbon group other than an alkenyl group, and n is an integer of 5 to 1500.

[0024] As the alkenyl group of R 1 in the above formula (I), alkenyl groups having 2 to 12 carbon atoms such as vinyl group, allyl group, butenyl group, pentenyl group, hexenyl group, heptenyl group, octenyl group, nonenyl group, decenyl group, undecenyl group, and dodecenyl group are exemplified, alkenyl groups having 2 to 6 carbon atoms are preferred, and particularly preferably a vinyl group.

[0025] As the monovalent hydrocarbon group other than the alkenyl group of R 2 in the above formula (I), for example, alkyl groups having 1 to 12 carbon atoms such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group, cyclohexyl group, heptyl group, octyl group, nonyl group, decyl group, undecenyl group, dodecyl group; aryl groups having 6 to 20 carbon atoms such as phenyl group, tolyl group, xylyl group, naphthyl group; aralkyl groups having 7 to 20 carbon atoms such as benzyl group, phenethyl group, phenylpropyl group; groups in which some or all of the hydrogen atoms of these groups are substituted with halogen atoms such as fluorine atom, chlorine atom, bromine atom are exemplified, preferably an alkyl group having 1 to 6 carbon atoms, and particularly preferably a methyl group.

[0026] In the above formula (I), n is preferably 10 or more, more preferably 25 or more, still more preferably 50 or more, preferentially 100 or more, and particularly preferably 300 or more. Also, n in the above formula (I) is preferably 1200 or less, more preferably 1000 or less, still more preferably 800 or less, preferentially 750 or less, and particularly preferably 700 or less.

[0027] The amount of the alkenyl group in the entire silicon atom-bonded functional group of component (A) is not particularly limited. For example, it is 0.01 mol% or more, preferably 0.05 mol% or more, more preferably 0.1 mol% or more, and still more preferably 0.15 mol% or more with respect to the amount of the entire silicon atom-bonded functional group. Also, the amount of the alkenyl group in the entire silicon atom-bonded functional group of component (A) is, for example, 5 mol% or less, preferably 3 mol% or less, more preferably 1 mol% or less, and still more preferably 0.5 mol% or less. The number of alkenyl groups can be determined, for example, by an analytical method such as a Fourier transform infrared spectrophotometer (FT-IR) or nuclear magnetic resonance (NMR), or the following titration method.

[0028] A method for quantifying the amount of alkenyl groups in each component by titration will be described. The alkenyl group content in the organopolysiloxane component can be accurately quantified by a titration method generally known as the Wijs method. The principle is described below. First, the alkenyl group in the organopolysiloxane raw material and iodine monochloride are subjected to an addition reaction as shown in formula (1). Next, by the reaction shown in formula (2), the excess iodine monochloride is reacted with potassium iodide to liberate iodine. Next, the liberated iodine is titrated with a sodium thiosulfate solution. Formula (1) CH2=CH- + 2ICl → CH2I-CHCl- + ICl (excess) Formula (2) ICl + KI → I2 + KCl The amount of alkenyl groups in the component can be quantified from the difference in the amount of sodium thiosulfate required for titration and the titration amount of a separately prepared blank solution.

[0029] (A) The amount of the alkenyl group-capped linear organopolysiloxane at both ends of the molecular chain is not particularly limited, but based on the total mass of all organopolysiloxane components contained in the thermosetting silicone composition according to the present invention, it is preferably contained in an amount of 20% by mass or more, more preferably 30% by mass or more, still more preferably 40% by mass or more, preferentially 50% by mass or more, and particularly preferably 60% by mass or more. Further, the alkenyl group-capped linear organopolysiloxane at both ends of the molecular chain of component (A) is contained, for example, in an amount of 90% by mass or less, preferably 80% by mass or less, more preferably 75% by mass or less, and still more preferably 70% by mass or less based on the total mass of all organopolysiloxane components.

[0030] (B) Resinous organopolysiloxane having at least two alkenyl groups at the molecular chain ends (B) Component is a resinous organopolysiloxane having at least two alkenyl groups at the molecular chain ends. In the present specification, the resinous organopolysiloxane means an organopolysiloxane having a branched or network structure in the molecular structure. Component (B) may contain one kind of resinous organopolysiloxane having at least two alkenyl groups at the molecular chain ends, or may contain a combination of two or more kinds of resinous organopolysiloxanes having at least two alkenyl groups at the molecular chain ends.

[0031] In one embodiment, the resinous organopolysiloxane of component (B) contains at least one siloxane unit (Q unit) represented by RSiO 4 / 2 in its molecular structure. The resinous organopolysiloxane of component (B) may or may not contain at least one siloxane unit (T unit) represented by RSiO 3 / 2 in its molecular structure, but preferably does not contain it. In a specific embodiment of the present invention, the resinous organopolysiloxane of component (B) is composed of a siloxane unit (M unit) represented by RSiO 1 / 2 and RSiO 4 / 2It can be an MQ resin composed of siloxane units (Q units) represented by

[0032] (B) The resinous organopolysiloxane of the component is preferably Average unit formula (II): (R 3 3SiO 1 / 2 ) a (R 3 2SiO 2 / 2 ) b (R 3 SiO 3 / 2 ) c (SiO 4 / 2 ) d (XO 1 / 2 ) e represented by, where in formula (II), R 3 is each independently a monovalent hydrocarbon group, provided that at least 2 of R 3 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, and 0 ≦ e ≦ 0.2, a + b + c + d = 1.0, and c + d > 0.

[0033] In the above formula (II) of component (B), as the monovalent hydrocarbon group of R 3 , there are alkyl groups having 1 to 12 carbon atoms such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group, cyclohexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group; aryl groups having 6 to 20 carbon atoms such as phenyl group, tolyl group, xylyl group, naphthyl group; aralkyl groups having 7 to 20 carbon atoms such as benzyl group, phenethyl group, phenylpropyl group; alkenyl groups having 2 to 12 carbon atoms such as vinyl group, allyl group, butenyl group, pentenyl group, hexenyl group, heptenyl group, octenyl group, nonenyl group, decenyl group, undecenyl group, dodecenyl group; groups in which some or all of the hydrogen atoms of these groups are substituted with halogen atoms such as fluorine atom, chlorine atom, bromine atom. R 3It is preferably selected from an alkyl group having 1 to 6 carbon atoms, preferably a methyl group, and an alkenyl group having 2 to 6 carbon atoms, preferably a vinyl group.

[0034] (In the formula (II) of component (B), X is a hydrogen atom or an alkyl group. As the alkyl group of X, an alkyl group having 1 to 3 carbon atoms is preferable, and specifically, a methyl group, an ethyl group, and a propyl group are exemplified.)

[0035] (In the above formula (II) of 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 still more preferably in the range of 0.3 ≦ a ≦ 0.6. In the above formula (II) of 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 the above formula (II) of 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 the above formula (II) of 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 still more preferably in the range of 0.3 ≦ d ≦ 0.6.)

[0036] (The alkenyl group-containing resinous organopolysiloxane of component (B) contains an alkenyl group at the molecular chain terminal. That is, the alkenyl group-containing resinous organopolysiloxane of component (B) has an alkenyl group in the siloxane unit (M unit) represented by R 3 3SiO 1 / 2 and does not contain an alkenyl group in the D unit and / or the T unit.)

[0037] (The molecular weight of the organopolysiloxane of component (B) is not particularly limited, but for example, the weight average molecular weight (Mw) in terms of standard polystyrene may be 1,000 to 100,000. The weight average molecular weight (Mw) can be measured by, for example, GPC.)

[0038] (B) The alkenyl group-containing resinous organopolysiloxane represented by the above formula (II) has at least two alkenyl groups per molecule. The amount of alkenyl groups in the total silicon atom-bonded functional groups of component (B) is not particularly limited. For example, it is 1 mol% or more, preferably 2 mol% or more, more preferably 4 mol% or more, and still more preferably 6 mol% or more based on the total amount of silicon atom-bonded functional groups. Also, the amount of alkenyl groups in the total silicon atom-bonded functional groups of component (A) is, for example, 20 mol% or less, preferably 15 mol% or less, more preferably 12 mol% or less, and still more preferably 10 mol% or less. Incidentally, the number of alkenyl groups can be determined by, for example, analytical methods such as Fourier transform infrared spectrophotometer (FT-IR), nuclear magnetic resonance (NMR), or the above titration method.

[0039] (B) The amount of the alkenyl group-containing resinous organopolysiloxane of component (B) is not particularly limited, but is preferably contained in an amount of 5% by mass or more, more preferably 10% by mass or more, still more preferably 15% by mass or more, preferentially 20% by mass or more, and particularly preferably 25% by mass or more based on the total mass of all the organopolysiloxane components contained in the thermosetting silicone composition according to the present invention. Also, the resinous alkenyl group-containing organopolysiloxane of component (B) is contained in an amount of 80% by mass or less, more preferably 70% by mass or less, and still more preferably 60% by mass or less based on the total mass of all the organopolysiloxane components.

[0040] (C) An organohydrogenpolysiloxane having at least two silicon atom-bonded hydrogen atoms in the side chain of the molecular chain The thermosetting silicone composition of the present invention contains, as a crosslinking agent, an organohydrogenpolysiloxane having at least two silicon atom-bonded hydrogen atoms in one molecule in the side chain of the molecular chain of component (C). Component (C) may use only one kind of organohydrogenpolysiloxane, or may use a combination of two or more kinds of organohydrogenpolysiloxanes.

[0041] Examples of the molecular structure of the organohydrogenpolysiloxane of component (C) include linear, linearly branched, branched chain, cyclic, and three-dimensional network structures. Preferably, it is a linear structure or a branched chain structure, and more preferably a linear structure. Component (C) may use an organohydrogenpolysiloxane having one type of structure, or may be used in combination with organohydrogenpolysiloxanes having two or more types of structures.

[0042] The silicon atom-bonded hydrogen atom of component (C) is a hydrogen atom bonded to a silicon atom other than the terminal silicon atom of the organohydrogenpolysiloxane. Examples of the silicon atom-bonded functional group other than the hydrogen atom in component (C) include monovalent hydrocarbon groups. Specifically, alkyl groups having 1 to 12 carbon atoms such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group, cyclohexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group; aryl groups having 6 to 20 carbon atoms such as phenyl group, tolyl group, xylyl group, naphthyl group; aralkyl groups having 7 to 20 carbon atoms such as benzyl group, phenethyl group, phenylpropyl group; and groups in which some or all of the hydrogen atoms of these groups are substituted with halogen atoms such as fluorine atom, chlorine atom, bromine atom. Note that the silicon atoms in component (C) may have a small amount of hydroxyl groups, alkoxy groups such as methoxy group and ethoxy group, as long as the object of the present invention is not impaired.

[0043] In one embodiment, the organohydrogenpolysiloxane of component (C) is preferably Structural formula (III): R 4 3SiO(R 5 2SiO) m SiR 4 3 represented by the formula (III), in the formula (III), R 4 are each independently a monovalent hydrocarbon group, and R 5 is a monovalent hydrocarbon group or a hydrogen atom, provided that at least two R 5is a hydrogen atom, and m is an integer from 3 to 200.

[0044] (C) In the above formula (III) of the component, R 4 and R 5 As the monovalent hydrocarbon group, there are alkyl groups having 1 to 12 carbon atoms such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group, cyclohexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group; aryl groups having 6 to 20 carbon atoms such as phenyl group, tolyl group, xylyl group, naphthyl group; aralkyl groups having 7 to 20 carbon atoms such as benzyl group, phenethyl group, phenylpropyl group; alkenyl groups having 2 to 12 carbon atoms such as vinyl group, allyl group, butenyl group, pentenyl group, hexenyl group, heptenyl group, octenyl group, nonenyl group, decenyl group, undecenyl group, dodecenyl group; groups in which some or all of the hydrogen atoms of these groups are substituted with halogen atoms such as fluorine atom, chlorine atom, bromine atom, preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group.

[0045] m in the above formula (III) is preferably 5 or more, more preferably 10 or more, still more preferably 20 or more, preferentially 30 or more, and particularly preferably 40 or more. Further, m in the above formula (III) is preferably 300 or less, more preferably 200 or less, still more preferably 150 or less, preferentially 100 or less, and particularly preferably 75 or less.

[0046] (C) The amount of the organohydrogenpolysiloxane is not particularly limited, but is preferably contained in an amount of 0.5% by mass or more, more preferably 1% by mass or more, still more preferably 2% by mass or more, preferentially 3% by mass or more, and particularly preferably 4% by mass or more based on the total mass of all the organopolysiloxane components contained in the thermosetting silicone composition according to the present invention. Further, the organopolysiloxane of component (C) is contained, for example, in an amount of 20% by mass or less, preferably 15% by mass or less, more preferably 10% by mass or less, and still more preferably 7% by mass or less based on the total mass of all the organopolysiloxane components.

[0047] Further, in another embodiment, the content of the organohydrogenpolysiloxane of component (C) is, for example, an amount such that the silicon-bonded hydrogen atoms in this component are 1.0 to 3.0 moles per mole of the silicon-bonded alkenyl groups in the thermosetting silicone composition, and preferably may be an amount such that they are 1.5 to 2.5 moles. The content of the silicon-bonded hydrogen atoms in component (C) can be determined, for example, by analysis using a Fourier transform infrared spectrophotometer (FT-IR), nuclear magnetic resonance (NMR), or the like.

[0048] In one embodiment of the present invention, when all of the silicon-bonded functional groups in the entire composition are used as a reference, the amount of the silicon-bonded hydrogen atoms in the entire composition is not particularly limited, but is preferably 0.54 mol% or more, and more preferably 0.82 mol% or more. Further, in another embodiment of the present invention, based on the total amount of the silicon-bonded functional groups contained in the organopolysiloxane component in the thermosetting silicone composition of the present invention, the amount of the silicon-bonded hydrogen atoms is not particularly limited, but is preferably 0.54 mol% or more, and more preferably 0.82 mol% or more.

[0049] The thermosetting silicone composition according to the present invention may contain, as a crosslinking agent in addition to the organohydrogenpolysiloxane having at least two silicon atom-bonded hydrogen atoms on the side chain of the molecular chain of the component (C), an organohydrogenpolysiloxane having a silicon atom-bonded hydrogen atom at the molecular chain end.

[0050] Examples of the molecular structure of the organohydrogenpolysiloxane having a silicon atom-bonded hydrogen atom at the molecular chain end include a linear structure, a linear structure having a partial branch, a branched chain structure, a cyclic structure, and a three-dimensional network structure. Preferably, it is a linear structure or a branched chain structure, and more preferably a linear structure. Such an organohydrogenpolysiloxane having a silicon atom-bonded hydrogen atom at the molecular chain end may be used alone or in combination of two or more.

[0051] The organohydrogenpolysiloxane having a silicon atom-bonded hydrogen atom at the linear molecular chain end is preferably a hydrosilyl group-terminated organohydrogenpolysiloxane. For example, dimethylpolysiloxane blocked with dimethylhydrogenoxysilyl groups at both ends of the molecular chain, and dimethylsiloxane-methylphenylsiloxane copolymer blocked with dimethylhydrogenoxysilyl groups at both ends of the molecular chain are exemplified.

[0052] Preferably, the amount of the hydrosilyl group-terminated organohydrogenpolysiloxane is not particularly limited, but is contained in an amount of 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 based on the total mass of all the organopolysiloxane components contained in the thermosetting silicone composition according to the present invention.

[0053] (D) Catalyst for curing reaction The thermosetting silicone composition of the present invention contains, as component (D), a catalyst for a curing reaction for curing an organopolysiloxane component. The thermosetting silicone composition according to the present invention may contain one type of catalyst (D) for the curing reaction, or may contain two or more types of catalysts (D) for the curing reaction.

[0054] (D) The curing catalyst for the component is a catalyst for promoting the curing of an addition reaction curing type silicone composition by hydrosilylation. Examples of such component (D) include platinum-based catalysts such as chloroplatinic acid, an alcohol solution of chloroplatinic acid, a complex of platinum and an olefin, a complex of platinum and 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, and a powder carrying platinum; palladium-based catalysts such as tetrakis(triphenylphosphine)palladium, palladium black, and a mixture with triphenylphosphine; and further, rhodium-based catalysts. In particular, a platinum-based catalyst is preferably used.

[0055] (D) The blending amount of the curing catalyst for the component is the amount of catalyst necessary for curing the thermosetting silicone composition of the present invention, and is not particularly limited. For example, when a platinum-based catalyst is used, the amount of platinum metal contained in this platinum-based catalyst is preferably in the range of 0.01 to 1000 ppm by weight in the silicone composition, and particularly preferably in the range of 0.1 to 500 ppm.

[0056] The thermosetting silicone composition of the present invention can be blended with optional components as long as the object of the present invention is not impaired. Examples of such optional components include adhesion promoters, silane coupling agents, reaction inhibitors, acetylene compounds, organic phosphorus compounds, vinyl group-containing siloxane compounds, ultraviolet absorbers, sensitizers, light stabilizers, antioxidants, ultraviolet absorbers, defoaming agents, leveling agents, inorganic fillers, surfactants, tackifiers, release agents, metal soaps, heat resistance-imparting agents, cold resistance-imparting agents, thermal conductivity fillers, flame retardancy-imparting agents, thixotropy-imparting agents, phosphors, solvents, and the like.

[0057] Adhesion promoter The thermosetting silicone composition of the present invention may contain an adhesion promoter. Preferably, the adhesion promoter is a silicone compound functionalized with an epoxy group or an alkoxy group. Examples of the adhesion promoter include an organosilane having a trialkoxysiloxy group (e.g., trimethoxysiloxy group, triethoxysiloxy group) or a trialkoxysilylalkyl group (e.g., trimethoxysilylethyl group, triethoxysilylethyl group), and a hydrosilyl group or an alkenyl group (e.g., vinyl group, allyl group), or a linear, branched or cyclic organosiloxane oligomer having about 4 to 20 silicon atoms; an organosilane having a trialkoxysiloxy group or a trialkoxysilylalkyl group and a methacryloxyalkyl group (e.g., 3-methacryloxypropyl group), or a linear, branched or cyclic organosiloxane oligomer having about 4 to 20 silicon atoms; an organosilane having a trialkoxysiloxy group or a trialkoxysilylalkyl group and an epoxy group-bonded alkyl group (e.g., 3-glycidoxypropyl group, 4-glycidoxybutyl group, 2-(3,4-epoxycyclohexyl)ethyl group, 3-(3,4-epoxycyclohexyl)propyl group), or a linear, branched or cyclic organosiloxane oligomer having about 4 to 20 silicon atoms; a reaction product of an aminoalkyltrialkoxysilane and an epoxy group-bonded alkyltrialkoxysilane, and an epoxy group-containing ethyl polysilicate.Specifically, vinyltrimethoxysilane, allyltrimethoxysilane, allyltriethoxysilane, hydrogen triethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, diethoxymethyl(3-(oxiranylmethoxy)propyl)silane, the reaction product of 3-glycidoxypropyltriethoxysilane and 3-aminopropyltriethoxysilane, the condensation reaction product of a methylvinylsiloxane oligomer with hydroxyl groups blocked at both ends of the molecular chain and 3-glycidoxypropyltrimethoxysilane, the condensation reaction product of a methylvinylsiloxane oligomer with hydroxyl groups blocked at both ends of the molecular chain and 3-methacryloxypropyltriethoxysilane, and tris(3-trimethoxysilylpropyl)isocyanurate are exemplified. The adhesion promoter in this composition may be a mixture of two or more of the above reaction products, and preferably, it is a mixture of the condensation reaction product of a methylvinylsiloxane oligomer with hydroxyl groups blocked at both ends of the molecular chain and 3-methacryloxypropyltriethoxysilane, and diethoxymethyl(3-(oxiranylmethoxy)propyl)silane. In this composition, the ratio of the above reaction products in the mixture of the adhesion promoter may be any ratio. For example, the ratio of two reaction products in the mixture of the adhesion promoter may be, for example, 1:10 (mass) to 10:1 (mass), and more specifically, it may be 2:1 (mass), 1:1 (mass), or 1:2 (mass). In this composition, the content of the adhesion promoter is not limited, but it is preferably in the range of 0.1 to 20 parts by mass, and more preferably in the range of 0.2 to 10 parts by mass, based on 100 parts by mass in total of the organopolysiloxane component.

[0058] Silane coupling agent The thermosetting silicone composition of the present invention may contain a silane coupling agent. Specific examples of the silane coupling agent include epoxy group-containing alkoxysilane compounds such as γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane; mercapto group-containing alkoxysilane compounds such as γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane; ureido group-containing alkoxysilane compounds such as γ-ureidopropyltriethoxysilane, γ-ureidopropyltrimethoxysilane, γ-(2-ureidoethyl)aminopropyltrimethoxysilane; isocyanate group-containing alkoxysilane compounds such as γ-isocyanatopropyltriethoxysilane, γ-isocyanatopropyltrimethoxysilane, γ-isocyanatopropylmethyldimethoxysilane, γ-isocyanatopropylmethyldiethoxysilane, γ-isocyanatopropylethyldimethoxysilane, γ-isocyanatopropylethyldiethoxysilane, γ-isocyanatopropyltrichlorosilane; and amino group-containing alkoxysilane compounds such as γ-(2-aminoethyl)aminopropylmethyldimethoxysilane, γ-(2-aminoethyl)aminopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane. The amount of the silane coupling agent is not particularly limited, but it is preferably in an amount of 2.0% by mass or less based on the total mass of all the organopolysiloxane components contained in the thermosetting silicone composition according to the present invention.

[0059] Reaction inhibitor The thermosetting silicone composition of the present invention may contain a reaction inhibitor for suppressing the curing reaction. Preferably, the reaction inhibitor is a compound functionalized with an alkene group or an alkylene group. Examples of the reaction inhibitor include alkynyl alcohols such as 1-ethynylcyclohexan-1-ol, 2-methyl-3-butyn-2-ol, 3,5-dimethyl-1-hexyn-3-ol, and 2-phenyl-3-butyn-2-ol; enyne compounds such as 3-methyl-3-penten-1-yne and 3,5-dimethyl-3-hexen-1-yne; alkynyloxysilanes such as 1,1-dimethylpropynyloxytrimethylsilane (methyl-tris(3-methyl-1-butyn-3-oxy)silane), bis(1,1-dimethylpropynyloxy)dimethylsilane, and bis(1,1-dimethylpropynyloxy)methylvinylsilane; and others, such as benzotriazole. In this composition, the content of this reaction inhibitor is not limited, but it is preferably in the range of 0.001 to 5 parts by mass, more preferably in the range of 0.01 to 1 part by mass, based on 100 parts by mass in total of the organopolysiloxane components.

[0060] Heat resistance imparting agent The thermosetting silicone composition of the present invention may contain a heat resistance imparting agent. The heat resistance imparting agent is not particularly limited, and examples thereof include iron oxide (red iron oxide), cerium oxide, cerium dimethylsilanolate, cerium fatty acid salt, cerium hydroxide, or zirconium compounds. The heat resistance imparting agent is preferably a cerium-containing organopolysiloxane. In this composition, the content of the heat resistance imparting agent is not limited, but it is preferably in the range of 0.1 to 20 parts by mass, more preferably in the range of 0.2 to 10 parts by mass, based on 100 parts by mass in total of the organopolysiloxane components.

[0061] The thermosetting silicone composition of the present invention can be cured in a short time, for example, it can be cured by heating for a time of less than 10 minutes. The heating temperature for curing the thermosetting silicone composition of the present invention is preferably above 100°C, more preferably a temperature of 150 - 200°C. Even when the thermosetting silicone composition of the present invention is cured in a short time, the cured product can exhibit excellent adhesiveness and durability under high temperature and high humidity conditions.

[0062] The thermosetting silicone composition of the present invention can be prepared by mixing each component. The mixing method of each component may be a conventionally known method and is not particularly limited, but usually, a uniform mixture is obtained by simple stirring. Also, mixing may be performed using a mixing device. There is no particular limitation on such a mixing device, and examples include single - shaft or twin - shaft continuous mixers, two - roll mills, Ross mixers, Hobart mixers, dental mixers, planetary mixers, kneader mixers, Henschel mixers, etc.

[0063] [Sealing agent] The present invention also relates to a sealing material containing the thermosetting silicone composition of the present invention. The sealing material of the present invention is preferably a sealing material for optical semiconductors. The shape of the sealing agent of the present invention is not particularly limited, but is preferably film - shaped or sheet - shaped. Therefore, the present invention also relates to a film obtained by solidifying the thermosetting silicone composition of the present invention. The film of the present invention can preferably be used as a film - shaped sealing material for encapsulating semiconductor elements. The semiconductor encapsulated by the sealing agent or film of the present invention is not particularly limited, and examples include semiconductors such as SiC and GaN, or optical semiconductors such as light - emitting diodes.

[0064] As a method for forming the thermosetting silicone composition of the present invention into a film or sheet form, conventionally known methods can be used. For example, it can be extruded into a film through an extruder provided with a predetermined die, or sandwiched between organic resin films such as polyolefin films and polyester films using calender rolls to form a uniform film, or formed into a film using a press adjusted to 40°C or lower. Examples of such methods are illustrated. It is also possible to laminate and continuously mold between organic resin films using calender rolls. The film-shaped sealing material thus formed can be cut into a required shape using a cutter or a punching device from a long roll.

[0065] The film thickness of the film or sheet-shaped sealing material of the present invention is not particularly limited, but is preferably in the range of 1 μm to 10 mm, or in the range of 5 μm to 5 mm.

[0066] According to the sealing agent of the present invention, since it contains the thermosetting silicone composition of the present invention, it has excellent adhesiveness and durability even under high temperature and high humidity, and thus can provide a highly reliable semiconductor device.

[0067] [Optical semiconductor device] The optical semiconductor device of the present invention is one in which an optical semiconductor element is sealed with the above-described sealing material of the present invention. In other words, the optical semiconductor element is sealed, coated, or adhered with a sealing material containing the above-described thermosetting silicone composition of the present invention. Examples of such optical semiconductor elements include light-emitting diodes (LEDs), semiconductor lasers, photodiodes, phototransistors, solid-state imaging devices, and light emitters and light receivers for photocouplers. In particular, a light-emitting diode (LED) is preferably used.

[0068] Since light emission occurs from the top, bottom, left, and right of a light-emitting diode (LED), the components that make up the light-emitting diode (LED) preferably do not absorb light, and materials with high light transmittance or high reflectivity are preferred. Therefore, the substrate on which the optoelectronic device is mounted also preferably uses a material with high light transmittance or high reflectivity. Examples of such substrates on which optoelectronic devices are mounted include conductive metals such as silver, gold, and copper; non-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.

[0069] The optoelectronic device of the present invention is encapsulated with the encapsulant of the present invention, which has excellent adhesiveness and durability even under high temperature and high humidity conditions, so it has high reliability.

Examples

[0070] The thermosetting silicone composition of the present invention will be described in detail with reference to the following examples and comparative examples.

[0071] In the following examples and comparative examples, the raw material components shown below were used. Here, Me represents a methyl group and Vi represents a vinyl group. Also, hereinafter, epoxy group and / or alkoxy group-functionalized silicone is a condensation reaction product of a hydroxyl group-blocked methylvinylsiloxane oligomer with both ends of the molecular chain and 3-glycidoxypropyltrimethoxysilane, and a 1:1 (mass) mixture of diethoxymethyl(3-(oxiranylmethoxy)propyl)silane.

[0072] (Example 1) ·Me2ViSiO(Me2SiO) 550 SiMe2Vi: 65% by mass ·(Me2ViSiO 1 / 2 ) 11 (Me3SiO 1 / 2 ) 34 (SiO 4 / 2 ) 55 : 30% by mass ·Me3SiO(MeHSiO) 50 SiMe3: 5 mass% · Platinum (Pt) catalyst compound: 0.005 parts by mass per 100 parts by mass of the above organopolysiloxane component · Methyl-tris(3-methyl-1-butyn-3-oxy)silane: 0.05 parts by mass per 100 parts by mass of the above organopolysiloxane component · Epoxy group and / or alkoxy group functionalized silicone: 0.5 parts by mass per 100 parts by mass of the above organopolysiloxane component

[0073] (Example 2) · Me2ViSiO(Me2SiO) 550 SiMe2Vi: 65 mass% · (Me2ViSiO 1 / 2 )6(Me3SiO 1 / 2 ) 36 (SiO 4 / 2 ) 58 : 30 mass% · Me3SiO(MeHSiO) 50 SiMe3: 5 mass% · Platinum (Pt) catalyst compound: 0.005 parts by mass per 100 parts by mass of the above organopolysiloxane component · Methyl-tris(3-methyl-1-butyn-3-oxy)silane: 0.05 parts by mass per 100 parts by mass of the above organopolysiloxane component · Epoxy group and / or alkoxy group functionalized silicone: 0.5 parts by mass per 100 parts by mass of the above organopolysiloxane component

[0074] (Example 3) · Me2ViSiO(Me2SiO) 550 SiMe2Vi: 65 mass% · (Me2ViSiO 1 / 2 ) 11 (Me3SiO 1 / 2 ) 34 (SiO 4 / 2 ) 55 : 30 mass% · Me3SiO(MeHSiO) 50 SiMe3: 5 mass% · Platinum (Pt) catalyst compound: 0.005 parts by mass per 100 parts by mass of the above organopolysiloxane component · Methyl-tris(3-methyl-1-butyn-3-oxy)silane: 0.05 parts by mass per 100 parts by mass of the above organopolysiloxane component · Epoxy group and / or alkoxy group functionalized silicone: 0.5 parts by mass per 100 parts by mass of the above organopolysiloxane component · Cerium-containing organopolysiloxane: 0.5 parts by mass per 100 parts by mass of the above organopolysiloxane component

[0075] (Comparative Example 1) · Me2ViSiO(Me2SiO) 550 SiMe2Vi: 99.5% by mass · Me3SiO(MeHSiO) 50 SiMe3: 0.5% by mass · Platinum (Pt) catalyst compound: 0.005 parts by mass per 100 parts by mass of the above organopolysiloxane component · 3,5-Dimethyl-1-hexyn-3-ol: 0.05 parts by mass per 100 parts by mass of the above organopolysiloxane component · Epoxy group and / or alkoxy group functionalized silicone: 0.5 parts by mass per 100 parts by mass of the above organopolysiloxane component

[0076] (Comparative Example 2) · Me2ViSiO(Me2SiO) 550 SiMe2Vi: 99.5% by mass · (Me2HSiO 1 / 2 ) 62.5 (SiO 4 / 2 ) 37.5 : 0.5% by mass · Platinum (Pt) catalyst compound: 0.005 parts by mass per 100 parts by mass of the above organopolysiloxane component · 3,5-Dimethyl-1-hexyn-3-ol: 0.05 parts by mass per 100 parts by mass of the above organopolysiloxane component · Epoxy group or alkoxy group functionalized silicone: 0.5 parts by mass per 100 parts by mass of the above organopolysiloxane component

[0077] Subsequent test The curable silicone compositions of Examples 1 to 3 and Comparative Examples 1 and 2 were placed on a glass substrate at 0.5 g and cured by heating at 200°C for 10 minutes to obtain cured products. The obtained cured products were held in an environment of 85°C and 85% humidity for 24 hours, and then the presence or absence of peeling between the glass substrate and the silicone cured product was confirmed. The cured products obtained from the curable silicone compositions of Examples 1 to 3 underwent 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 peeling between the substrate and the material. Therefore, it was confirmed that the thermosetting silicone composition according to the present invention exhibits excellent adhesiveness and durability even under high temperature and high humidity conditions.

Industrial applicability

[0078] The thermosetting silicone composition of the present invention is useful as a sealing agent, a coating agent, or an adhesive for optical semiconductor elements such as light-emitting diodes (LEDs), semiconductor lasers, photodiodes, phototransistors, solid-state imaging, and light-emitting and light-receiving bodies for photocouplers. Further, the optical semiconductor device of the present invention is useful as an optical semiconductor device such as an optical device, an optical instrument, a lighting device, and a lighting apparatus.

Claims

1. (A) a linear organopolysiloxane blocked at both ends of the molecular chain with alkenyl groups and (B) a resinous organopolysiloxane having at least two alkenyl groups at the ends of the molecular chain and (C) an organohydrogenpolysiloxane having at least two silicon atom-bonded hydrogen atoms in the side chains of the molecular chain and (D) a catalyst for the curing reaction A thermosetting silicone composition comprising the same.

2. The thermosetting silicone composition according to Claim 1, wherein the organohydrogenpolysiloxane as the component (C) is linear.

3. The thermosetting silicone composition according to Claim 1 or 2, wherein the linear organopolysiloxane blocked at both ends of the molecular chain as the component (A) is represented by Structural formula: R １ R ２ ２ SiO(R ２ ２ SiO) ｎ SiR １ R ２ ２ (wherein R １ is an alkenyl group, and each of R ２ is independently a monovalent hydrocarbon group other than an alkenyl group, and n is an integer of 5 to 1500)

4. A resinous organopolysiloxane having at least two alkenyl groups at the molecular chain terminals of the component (B) is RSiO １／２ a siloxane unit represented by and a siloxane unit represented by RSiO ４／２ The thermosetting silicone composition according to any one of claims 1 to 3, which is composed of

5. An encapsulant comprising the thermosetting silicone composition according to any one of Claims 1 to 4.

6. An optical semiconductor device, characterized in that it is encapsulated with the encapsulant according to Claim 5.