Addition-curable silicone resin composition, cured product thereof, and optical semiconductor device

Abstract

To provide an addition-curable silicone resin composition that gives a cured product excellent in adhesion to a substrate and thermal impact resistance, and a highly reliable optical semiconductor device that is sealed with the cured product.SOLUTION: The present invention relates to an addition-curable silicone resin composition characterized by comprising (A) a linear organopolysiloxane having, in one molecule, two or more silicon-atom-bonded alkenyl groups, (B) an organohydrogenpolysiloxane having, in one molecule, two or more silicon-atom-bonded hydrogen atoms and having no aliphatic unsaturated bond, (C) a polyorganosilsesquioxane having, in one molecule, one or more silicon-atom-bonded alkenyl groups, one or more silicon-atom-bonded alkoxy groups, and one or more silicon-atom-bonded epoxy-containing groups, and (D) a platinum-group metal-based catalyst.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an addition-curable silicone resin composition, a cured product thereof, and an optical semiconductor device using the cured product. [Background technology]

[0002] Devices that have light-emitting diodes (LEDs) as optical semiconductor elements are generally constructed by sealing LEDs mounted on a substrate with a sealing material made of transparent resin. Silicone resin compositions have attracted attention as sealing materials from the viewpoint of heat resistance and resistance to heat discoloration, and addition reaction curing type silicone resin compositions can be cured in a short time by heating, making them highly productive and therefore used as LED sealing materials.

[0003] However, as the output of LED elements improves, the elements also generate more heat, which can cause the encapsulant to peel off from the LED package substrate or cause cracks in the resin, so there was a need for encapsulant materials with even greater durability.

[0004] Therefore, as a method for improving the initial adhesion and adhesion durability to a substrate, a silicone resin composition to which an adhesion promoter made of polysiloxane having an epoxy group introduced therein has been proposed in Patent Documents 1 and 2. Thus, there is a demand for an encapsulating material for optical semiconductor elements that is excellent in adhesion to a substrate and in thermal shock resistance. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2007-327019 A [Patent Document 2] JP 2019-085467 A Summary of the Invention [Problem to be solved by the invention]

[0006] As mentioned above, as the output of LED elements improves, the elements generate more heat, which can cause the encapsulant to peel off from the LED package substrate or cause cracks to form in the resin, so there is a demand for encapsulant materials with even greater durability.

[0007] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an addition-curable silicone resin composition that gives a cured product that has excellent adhesion to a substrate and excellent thermal shock resistance, and a highly reliable optical semiconductor device that is encapsulated with the cured product. [Means for solving the problem]

[0008] In order to solve the above problems, the present invention provides (A) a linear organopolysiloxane having two or more alkenyl groups bonded to silicon atoms in each molecule; (B) an organohydrogenpolysiloxane having two or more hydrogen atoms bonded to silicon atoms in one molecule and having no aliphatic unsaturated bonds; (C) a polyorganosilsesquioxane having, per molecule, one or more alkenyl groups bonded to silicon atoms, one or more alkoxy groups bonded to silicon atoms, and one or more epoxy-containing groups bonded to silicon atoms; and (D)Platinum group metal catalyst The present invention provides an addition-curable silicone resin composition comprising:

[0009] The addition-curable silicone resin composition of the present invention can give a cured product that has excellent adhesion and thermal shock resistance.

[0010] In the present invention, the component (A) is preferably a linear organopolysiloxane represented by the following general formula (1). [ka] (In the formula, R 1are independently a methyl group, a phenyl group, or a vinyl group, a is a number from 1 to 200, and b is a number from 0 to 100. The siloxane units in the parentheses to which a has been added and the siloxane units in the parentheses to which b has been added may be arranged randomly, in blocks, or alternately.

[0011] Such a compound can be suitably used as component (A) in the addition-curable silicone resin composition of the present invention.

[0012] In the present invention, the component (B) is preferably a linear organohydrogenpolysiloxane represented by the following general formula (2). [ka] (In the formula, R 2 are independently a methyl group or a phenyl group, c is a number from 1 to 10, and d is a number from 0 to 10. The siloxane units in the parentheses to which c has been added and the siloxane units in the parentheses to which d has been added may be arranged randomly, in blocks, or alternately.

[0013] Such a compound can be suitably used as component (B) in the addition-curable silicone resin composition of the present invention.

[0014] In the present invention, the component (C) is preferably a polyorganosilsesquioxane represented by the following formula (3). [R 3 Si(OR 6 ) h O 1.5-h ] e [R 4 Si(OR 6 ) i O 1.5-i ] f [R 5 Si(OR 6 ) j O 1.5-j ] g (3) (In the formula, R 3are independently a methyl group or a phenyl group, R 4 is a vinyl group, and R 5 is an alkyl group having 3 to 8 carbon atoms substituted with a glycidyloxy group, and R 6 are independently a methyl group or an ethyl group, e, f, and g are numbers that satisfy e≧0, f>0, g>0, and e+f+g=1, and h, i, and j are numbers that satisfy 0≦h≦1.5, 0≦i≦1.5, 0≦j≦1.5, and h+i+j>0.

[0015] A composition containing such component (C) can give a cured product with superior adhesion and thermal shock resistance.

[0016] Furthermore, it is preferable that the addition-curable silicone resin composition of the present invention further contains, as component (E), a branched organopolysiloxane having an alkenyl group bonded to a silicon atom.

[0017] Such an addition-curable silicone composition can give a cured product with superior mechanical strength.

[0018] The present invention also provides a cured product obtained by curing the above addition-curable silicone composition.

[0019] Such a cured product will have high adhesiveness and high resistance to thermal shock.

[0020] Furthermore, the present invention provides an optical semiconductor device in which an optical semiconductor element is encapsulated with the above-mentioned cured product.

[0021] The cured product of the present invention has high adhesion and high resistance to thermal shock. Therefore, an optical semiconductor device in which an optical semiconductor element is encapsulated with such a cured product is unlikely to suffer from problems such as peeling and is highly reliable. Effect of the Invention

[0022] As described above, the addition-curable silicone resin composition of the present invention can provide a cured product having high adhesiveness and high thermal shock resistance. Therefore, such a cured product of the present invention can be suitably used as an encapsulation material for optical semiconductor elements such as LED elements. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] As described above, there has been a need for the development of an addition-curable silicone composition that gives a cured product that has high adhesion and high thermal shock resistance, and an optical semiconductor device in which an optical semiconductor element is encapsulated with the cured product, resulting in a highly reliable optical semiconductor device.

[0024] As a result of extensive investigations into the above-mentioned problems, the present inventors discovered that an addition-curable silicone composition containing the components (A), (B), (C), and (D) described below could solve the above-mentioned problems, and thus completed the present invention.

[0025] That is, the present invention provides: (A) a linear organopolysiloxane having two or more alkenyl groups bonded to silicon atoms in each molecule; (B) an organohydrogenpolysiloxane having two or more hydrogen atoms bonded to silicon atoms in one molecule and having no aliphatic unsaturated bonds; (C) a polyorganosilsesquioxane having, per molecule, one or more alkenyl groups bonded to silicon atoms, one or more alkoxy groups bonded to silicon atoms, and one or more epoxy-containing groups bonded to silicon atoms; and (D)Platinum group metal catalyst The addition-curable silicone resin composition comprises:

[0026] The present invention will be described in detail below, but the present invention is not limited thereto.

[0027] [Addition-curable silicone composition] The addition-curable silicone composition of the present invention contains the following components (A), (B), (C), and (D). Each component will be described in detail below.

[0028] <Component (A)> Component (A) is a linear organopolysiloxane having two or more alkenyl groups bonded to silicon atoms in each molecule. Component (A) contains alkenyl groups and cures by crosslinking with component (B), which will be described later, via a hydrosilylation reaction.

[0029] The alkenyl group of the component (A) is preferably an alkenyl group having 2 to 10 carbon atoms, particularly 2 to 6 carbon atoms, such as a vinyl group, an allyl group, or an ethynyl group, with a vinyl group being particularly preferred.

[0030] Substituents other than alkenyl groups bonded to silicon atoms in component (A) include substituted or unsubstituted monovalent hydrocarbon groups that do not have an aliphatic unsaturated bond, with substituted or unsubstituted monovalent hydrocarbon groups having 1 to 8 carbon atoms being preferred. Specific examples include alkyl groups such as methyl, ethyl, propyl, and butyl groups, cycloalkyl groups such as cyclopentyl and cyclohexyl groups, aryl groups such as phenyl, tolyl, and xylyl groups, aralkyl groups such as benzyl and phenylethyl groups, and halogenated hydrocarbon groups such as chloromethyl, chloropropyl, and chlorocyclohexyl groups, with methyl and phenyl groups being particularly preferred.

[0031] The component (A) is preferably a linear organopolysiloxane represented by the following general formula (1). [ka] (In the formula, R 1 are independently a methyl group, a phenyl group, or a vinyl group, a is a number from 1 to 200, and b is a number from 0 to 100. The siloxane units in the parentheses to which a has been added and the siloxane units in the parentheses to which b has been added may be arranged randomly, in blocks, or alternately.

[0032] Specific examples of the linear organopolysiloxane include those represented by the following formula: [ka] [ka] [ka] (In the above formula, the siloxane units in parentheses may be arranged in any order.)

[0033] The component (A) may use either a single type alone, or two or more types in combination.

[0034] From the viewpoint of workability, the viscosity of component (A) is preferably in the range of 100 to 100,000 mPa·s. In the present invention, the viscosity is measured at 25° C. using a rotational viscometer unless otherwise specified.

[0035] <(B) component> Component (B) is an organohydrogenpolysiloxane that has two or more hydrogen atoms bonded to silicon atoms (i.e., Si-H groups) per molecule and has no aliphatic unsaturated bonds, and acts as a crosslinking agent that crosslinks with the alkenyl groups contained in component (A) via a hydrosilylation reaction.

[0036] Substituents other than hydrogen atoms bonded to silicon atoms in component (B) include substituted or unsubstituted monovalent hydrocarbon groups that do not have an aliphatic unsaturated bond, and preferably substituted or unsubstituted monovalent hydrocarbon groups having 1 to 8 carbon atoms. Specific examples include alkyl groups such as methyl, ethyl, propyl, and butyl groups, cycloalkyl groups such as cyclopentyl and cyclohexyl groups, aryl groups such as phenyl, tolyl, and xylyl groups, aralkyl groups such as benzyl and phenylethyl groups, and halogenated hydrocarbon groups such as chloromethyl, chloropropyl, and chlorocyclohexyl groups, and more preferably methyl and phenyl groups.

[0037] The molecular structure of the organohydrogenpolysiloxane of component (B) may be linear, cyclic, branched, or a three-dimensional network structure, but linear structure is preferred, and the number of silicon atoms in one molecule is preferably 2 to 100, and more preferably 3 to 20.

[0038] Examples of organohydrogenpolysiloxanes of component (B) include 1,1,3,3-tetramethyldisiloxane, 1,3,5,7-tetramethylcyclotetrasiloxane, tris(hydrogendimethylsiloxy)methylsilane, tris(hydrogendimethylsiloxy)phenylsilane, methylhydrogencyclopolysiloxane, methylhydrogensiloxane-dimethylsiloxane cyclic copolymer, methylhydrogenpolysiloxane blocked at both ends with trimethylsiloxy groups, dimethylsiloxane-methylhydrogensiloxane copolymer blocked at both ends with trimethylsiloxy groups, dimethylpolysiloxane blocked at both ends with dimethylhydrogensiloxy groups, methylhydrogenpolysiloxane blocked at both ends with dimethylhydrogensiloxy groups, Dimethylhydrogensiloxy-blocked dimethylsiloxane-methylhydrogensiloxane copolymer, both ends blocked by trimethylsiloxy-blocked methylhydrogensiloxane-diphenylsiloxane copolymer, both ends blocked by trimethylsiloxy-blocked methylhydrogensiloxane-diphenylsiloxane-dimethylsiloxane copolymer, both ends blocked by trimethylsiloxy-blocked methylhydrogensiloxane-methylphenylsiloxane-dimethylsiloxane copolymer, both ends blocked by dimethylhydrogensiloxy-blocked methylhydrogensiloxane-dimethylsiloxane-diphenylsiloxane copolymer, both ends blocked by dimethylhydrogensiloxy-blocked methylhydrogensiloxane-dimethylsiloxane-methylphenylsiloxane copolymer, (CH 3 ) 2 HSiO 1 / 2 Units and (CH 3 ) 3 SiO 1 / 2 Units and SiO 4 / 2 A copolymer consisting of (CH 3 ) 2 HSiO 1 / 2 Units and SiO4 / 2 A copolymer consisting of (CH 3 ) 2 HSiO 1 / 2 Units and SiO 4 / 2 Units and (C 6 H 5 ) 3 SiO 1 / 2 and copolymers consisting of a unit.

[0039] The component (B) is preferably a linear organohydrogenpolysiloxane represented by the following general formula (2). [ka] (In the formula, R 2 are independently a methyl group or a phenyl group, c is a number from 1 to 10, and d is a number from 0 to 10. The siloxane units in the parentheses to which c has been added and the siloxane units in the parentheses to which d has been added may be arranged randomly, in blocks, or alternately.

[0040] Specific examples of the linear organohydrogenpolysiloxane include those represented by the following formula: [ka] [ka] (In the above formula, the siloxane units in parentheses may be arranged in any order.)

[0041] The viscosity of component (B) at 25° C. is preferably no greater than 100 mPa·s, and more preferably in the range of 5 to 100 mPa·s.

[0042] The organohydrogenpolysiloxane of component (B) may use either a single compound, or a combination of two or more different compounds.

[0043] From the viewpoint of crosslinking balance, the blending amount of the (B) component is an amount such that the number of hydrogen atoms (Si-H groups) bonded to silicon atoms in the (B) component is preferably 0.5 to 5.0 times, more preferably 0.7 to 3.0 times, the total number of alkenyl groups in the composition of the present invention, specifically, the total number of alkenyl groups bonded to all silicon atoms in the (A) component and the (C) and (E) components described below. Within such a range, crosslinking proceeds sufficiently, and a cured product with excellent hardness can be obtained.

[0044] <(C) component> The (C) component is a polyorganosilsesquioxane having at least one alkenyl group bonded to a silicon atom, at least one alkoxy group bonded to a silicon atom, and at least one epoxy-containing group bonded to a silicon atom in one molecule. For example, it can be obtained by partial hydrolysis and condensation of an organotrialkoxysilane mixture containing a trialkoxysilane having an alkenyl group bonded to a silicon atom and a trialkoxysilane having an epoxy-containing group bonded to a silicon atom. The alkenyl group in the (C) component, like that in the (A) component, is incorporated into the cured product by hydrosilylation reaction with the Si-H group in the (B) component, and the alkoxy group and epoxy-containing group, which are functional groups that impart adhesiveness in the (C) component, are fixed to the cured product via covalent bonds, thereby imparting high adhesiveness between the adherend and the silicone cured product. In addition, the (C) component has a network structure composed of T units, and by being incorporated into the cured product, a cured product with excellent thermal shock resistance can be obtained.

[0045] The alkenyl group of the component (C) is preferably an alkenyl group having 2 to 10 carbon atoms, particularly 2 to 6 carbon atoms, such as a vinyl group, an allyl group, or an ethynyl group, with a vinyl group being particularly preferred.

[0046] As the alkoxy group of component (C), methoxy and ethoxy groups are preferred.

[0047] Examples of the epoxy-containing group of component (C) include a glycidyl group, a glycidyloxy group, an alkyl group substituted with a glycidyloxy group, and a 2-(3,4-epoxycyclohexyl)ethyl group. Of these, an alkyl group having 3 to 8 carbon atoms substituted with a glycidyloxy group is preferred. Specific examples include a 3-glycidyloxypropyl group and an 8-glycidyloxyoctyl group.

[0048] Substituents bonded to silicon atoms of component (C) other than alkenyl groups, alkoxy groups, and epoxy-containing groups include substituted or unsubstituted monovalent hydrocarbon groups that do not have an aliphatic unsaturated bond, an alkoxy group, or an epoxy group, with substituted or unsubstituted monovalent hydrocarbon groups having 1 to 8 carbon atoms being preferred. Specific examples include alkyl groups such as methyl, ethyl, propyl, and butyl groups, cycloalkyl groups such as cyclopentyl and cyclohexyl groups, aryl groups such as phenyl, tolyl, and xylyl groups, aralkyl groups such as benzyl and phenylethyl groups, and halogenated hydrocarbon groups such as chloromethyl, chloropropyl, and chlorocyclohexyl groups, with methyl and phenyl groups being particularly preferred.

[0049] The component (C) is preferably a polyorganosilsesquioxane represented by the following formula (3). [R 3 Si(OR 6 ) h O 1.5-h ] e [R 4 Si(OR 6 ) i O 1.5-i ] f [R 5 Si(OR 6 ) j O 1.5-j ] g (3) (In the formula, R 3 are independently a methyl group or a phenyl group, R 4 is a vinyl group, and R 5 is an alkyl group having 3 to 8 carbon atoms substituted with a glycidyloxy group, and R 6are independently a methyl group or an ethyl group, e, f, and g are numbers that satisfy e≧0, f>0, g>0, and e+f+g=1, and h, i, and j are numbers that satisfy 0≦h≦1.5, 0≦i≦1.5, 0≦j≦1.5, and h+i+j>0.

[0050] The above e is preferably a number from 0 to 0.5, the above f is preferably a number from 0.2 to 0.6, and the above g is preferably a number from 0.3 to 0.6.

[0051] Each of the above h, i and j is preferably a number from 0.2 to 0.6.

[0052] Component (C) is preferably liquid, and from the viewpoints of isolation, workability, and compatibility with components (A) and (B), a weight-average molecular weight in the range of 500 to 10,000 is preferred. The weight-average molecular weight is a value calculated using standard polystyrene standards by gel permeation chromatography (GPC).

[0053] The component (C) may use either a single compound, or a combination of two or more different compounds.

[0054] From the viewpoint of the storage stability of the silicone resin composition of the present invention and the adhesiveness of the resulting cured product, the (C) component is preferably added in an amount of 1 to 25 parts by mass per 100 parts by mass of the total of the (A) component, the (B) component, and, if present, the (E) component described below.

[0055] <(D) component> The platinum group metal catalyst of component (D) promotes the addition reaction between alkenyl groups in component (A), component (C), and, if present, component (E) described below, and Si-H groups in component (B).

[0056] The platinum group metal catalyst of component (D) is not particularly limited, and examples thereof include platinum group metals such as platinum, palladium, and rhodium; platinum compounds such as chloroplatinic acid, alcohol-modified chloroplatinic acid, and coordination compounds of chloroplatinic acid with olefins, vinylsiloxanes, or acetylene compounds; and platinum group metal compounds such as tetrakis(triphenylphosphine)palladium and chlorotris(triphenylphosphine)rhodium, with platinum compounds being particularly preferred.

[0057] The component (D) may be diluted in advance with organopolysiloxane in order to improve compatibility within the composition, and the component (D) may be used either alone or in combination of two or more different types.

[0058] The amount of component (D) to be blended may be an effective amount as a catalyst, but is preferably 1 to 500 ppm, more preferably 3 to 100 ppm, calculated as the mass of platinum group metal element, relative to the total of components (A), (B), (C), and, if present, component (E) described below. If this range is satisfied, the reaction rate of the addition reaction becomes appropriate, and a cured product having high strength can be obtained.

[0059] <(E) component> The silicone resin composition of the present invention may contain, as component (E), a branched organopolysiloxane having alkenyl groups bonded to silicon atoms.

[0060] The component (E) is preferably a branched organopolysiloxane represented by the following formula (4). (R 7 3 SiO 1 / 2 ) k (R 8 R 7 2 SiO 1 / 2 ) l (R 7 2 SiO) m (R 7 R 8 SiO) n (R 7SiO 3 / 2 ) o (R 8 SiO 3 / 2 ) p (SiO 4 / 2 ) q (4) (In the formula, R 7 are independently substituted or unsubstituted monovalent hydrocarbon groups having no aliphatic unsaturated bonds, R 8 are independently alkenyl groups. k, l, m, n, o, p, and q are numbers that satisfy k≧0, l≧0, m≧0, n≧0, o≧0, p≧0, and q≧0, with the proviso that l+n+p>0, o+p+q>0, and k+l+m+n+o+p+q=1.

[0061] Above R 7 The substituted or unsubstituted monovalent hydrocarbon group having no aliphatic unsaturated bonds is preferably a substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms, specific examples of which include alkyl groups such as methyl, ethyl, propyl, and butyl groups; cycloalkyl groups such as cyclopentyl and cyclohexyl groups; aryl groups such as phenyl, tolyl, and xylyl groups; aralkyl groups such as benzyl and phenylethyl groups; and halogenated hydrocarbon groups such as chloromethyl, chloropropyl, and chlorocyclohexyl groups, with methyl and phenyl groups being particularly preferred.

[0062] Above R 8 The alkenyl group includes alkenyl groups having 2 to 10 carbon atoms, preferably 2 to 6 carbon atoms, such as a vinyl group, an allyl group, and an ethynyl group, and a vinyl group is particularly preferred.

[0063] In component (E), the content of alkenyl groups bonded to silicon atoms is preferably within the range of 0.01 to 1 mol, and more preferably within the range of 0.1 to 0.6 mol, per 100 g of component (E). When the content is within the range of 0.01 to 1 mol, the crosslinking reaction proceeds sufficiently, resulting in a cured product with higher hardness.

[0064] In the above formula (4), o, p, and q are numbers that satisfy o+p+q>0 (i.e., a branched structure is essential), but are preferably numbers that satisfy 0.05≦o+p+q≦0.9, and more preferably numbers that satisfy 0.1≦o+p+q≦0.7.

[0065] Specific examples of the branched organopolysiloxane of component (E) include the following: [(CH 3 ) 3 SiO 1 / 2 ] 0.1 [(CH 2 =CH)(CH 3 ) 2 SiO 1 / 2 ] 0.2 [SiO 4 / 2 ] 0.7 , [(CH 3 ) 3 SiO 1 / 2 ] 0.1 [(CH 2 =CH)(CH 3 ) 2 SiO 1 / 2 ] 0.2 [(CH 3 )SiO 3 / 2 ] 0.7 , [(CH 3 ) 3 SiO 1 / 2 ] 0.3 [(CH 2 =CH)(CH 3 ) 2 SiO 1 / 2 ] 0.1 [(C 6 H 5 ) 2 SiO 2 / 2 ] 0.45 [SiO 4 / 2 ] 0.15 , [(CH 3 ) 3 SiO 1 / 2 ] 0.3 [(CH 2 =CH)(CH 3 )SiO 2 / 2 ] 0.1 [(C 6 H5 ) 2 SiO 2 / 2 ] 0.45 [SiO 4 / 2 ] 0.15 , [(CH 2 =CH)(CH 3 )(C 6 H 5 )SiO 1 / 2 ] 0.2 [(C 6 H 5 ) 2 SiO 2 / 2 ] 0.35 [SiO 4 / 2 ] 0.45

[0066] The component (E) may use either a single compound, or a combination of two or more different compounds.

[0067] From the standpoint of ease of isolation, the organopolysiloxane of component (E) is preferably a three-dimensional network organopolysiloxane resin that is waxy or solid at 23°C.

[0068] When component (E) is used, its amount is preferably in the range of 1 to 50 mass %, and more preferably in the range of 5 to 25 mass %, based on the total mass of components (A) and (E), from the viewpoints of hardness and adhesion of the resulting cured product.

[0069] <Other ingredients> The composition of the present invention may contain other components, such as those exemplified below, in addition to the above components (A) to (E).

[0070] (Adhesion improver) The composition of the present invention may contain an adhesion improver other than the component (C) in order to improve adhesion to resins, etc. As the adhesion improver, from the viewpoint of imparting self-adhesiveness to the composition of the present invention, which is an addition reaction curing type, organosilicon compounds such as silanes and siloxanes, non-silicone organic compounds, etc., containing functional groups that impart adhesiveness are used.

[0071] Specific examples of functional groups that impart adhesiveness include alkenyl groups such as vinyl groups and allyl groups bonded to silicon atoms, and hydrogen atoms (Si-H groups); epoxy groups (e.g., 3-glycidoxypropyl group, 2-(3,4-epoxycyclohexyl)ethyl group, etc.), acryloxy groups (e.g., 3-acryloxypropyl group, etc.) or methacryloxy groups (e.g., 3-methacryloxypropyl group, etc.) bonded to silicon atoms via carbon atoms; alkoxysilyl groups (e.g., trimethoxysilyl group, triethoxysilyl group, methyldimethoxysilyl group, and other alkoxysilyl groups bonded to silicon atoms via alkylene groups which may contain 1 to 2 ester structures, urethane structures, or ether structures).

[0072] Examples of organosilicon compounds containing a functional group that imparts adhesiveness include silane coupling agents, siloxanes having an alkoxysilyl group and an organic functional group, and compounds in which an alkoxysilyl group has been introduced into an organic compound having a reactive organic group.

[0073] Examples of non-silicone organic compounds include organic acid allyl esters, epoxy group ring-opening catalysts, organic titanium compounds, organic zirconium compounds, and organic aluminum compounds.

[0074] (Reaction inhibitor) A reaction inhibitor may be added to the composition of the present invention in order to adjust the curing rate.

[0075] Examples of reaction inhibitors include phosphorus-containing compounds such as triphenylphosphine; nitrogen-containing compounds such as tributylamine, tetramethylethylenediamine, and benzotriazole; sulfur-containing compounds; acetylene compounds; hydroperoxy compounds; maleic acid derivatives; 1-ethynylcyclohexanol, 3,5-dimethyl-1-hexyn-3-ol, and ethynylmethyldecylcarbinol.

[0076] Since the degree of the curing inhibition effect of the reaction inhibitor varies depending on the chemical structure of the reaction inhibitor, it is desirable to adjust the amount of the reaction inhibitor to an optimal amount for each reaction inhibitor used. The amount is preferably 0.001 to 5 parts by mass per 100 parts by mass of the total of components (A) to (E). If the amount is 0.001 part by mass or more, the long-term storage stability of the composition at room temperature can be sufficiently obtained. If the amount is 5 parts by mass or less, there is no risk of the curing of the composition being inhibited.

[0077] (Filler) In addition to fumed silica, the composition of the present invention may contain inorganic fillers such as crystalline silica, hollow fillers, and silsesquioxanes, as well as fillers obtained by subjecting the surfaces of these fillers to hydrophobic treatment with organosilicon compounds such as organoalkoxysilane compounds, organochlorosilane compounds, organosilazane compounds, and low-molecular-weight siloxane compounds; silicone rubber powder, silicone resin powder, and the like.

[0078] The filler should have a specific surface area (BET method) of 50 m from the viewpoint of imparting thixotropy to the composition of the present invention and reinforcing properties to the cured product. 2 / g or more, and more preferably 50 to 400m 2 / g, particularly preferably 100 to 300m 2 / g.

[0079] It is also preferable to use a filler that has been treated with an organosilicon compound, such as methylchlorosilanes, such as trimethylchlorosilane, dimethyldichlorosilane, and methyltrichlorosilane, or hexaorganodisilazanes, such as dimethylpolysiloxane, hexamethyldisilazane, divinyltetramethyldisilazane, and dimethyltetravinyldisilazane.

[0080] Examples of such fillers include Reolosil DM30 (manufactured by Tokuyama Corp.), Aerosil NSX-200 (manufactured by Nippon Aerosil Co., Ltd.), and Musil 120A (manufactured by Shin-Etsu Chemical Co., Ltd.).

[0081] When a filler is used, the blending amount is preferably 0.1 to 20 parts by mass, more preferably 1 to 10 parts by mass, per 100 parts by mass of the total of the (A) to (E) components. Within such a range, the precipitation of the fumed silica in the composition can be suppressed, and sufficient reinforcing properties can be obtained. In addition, there is no risk of excessive thixotropy being imparted, which would reduce workability.

[0082] From the viewpoint of workability when sealing a semiconductor device, the viscosity of the addition-curable silicone resin composition of the present invention at 25°C is preferably 0.1 to 50 Pa·s, and more preferably 1 to 10 Pa·s.

[0083] [Cured product] Furthermore, the present invention provides a cured product of the addition-curable silicone composition (cured silicone product).

[0084] The addition-curable silicone composition of the present invention may be cured under known conditions, for example at 100 to 180° C. for 10 minutes to 5 hours.

[0085] The cured product of the addition-curable silicone composition of the present invention has high adhesion to resin substrates and particularly to metal substrates, and is capable of suppressing peeling of the resin due to thermal shock, making it useful as a sealant. As described above, the silicone cured product of the present invention can be used as an adhesive with high adhesion to substrates, etc.

[0086] [Optical semiconductor device] Furthermore, the present invention provides an optical semiconductor device in which an optical semiconductor element is encapsulated with the above-mentioned cured product. Examples of optical semiconductor elements (optical elements) that can be encapsulated with an encapsulant made of the composition of the present invention include LEDs, semiconductor lasers, photodiodes, phototransistors, solar cells, CCDs, etc. Such optical elements can be encapsulated by applying an encapsulating material made of the composition of the present invention to the optical element, and curing the applied encapsulating material under known curing conditions and by known curing methods, specifically as described above. EXAMPLES

[0087] The present invention will be specifically described below using synthesis examples, examples, and comparative examples, but the present invention is not limited to these. The viscosity is a value measured at 25°C using a rotational viscometer. GPC analysis was performed using HLC-8320GPC manufactured by Tosoh Corporation.

[0088] The abbreviations for each siloxane unit and functional group have the following meanings: M: (CH 3 ) 3 SiO 1 / 2 M Vi :(CH 2 =CH)(CH 3 ) 2 SiO 1 / 2 M 3Vi :(CH 2 =CH) 3 SiO 1 / 2 D: (CH 3 ) 2 SiO 2 / 2 D H :H(CH 3 )SiO 2 / 2 D 2φ :(C 6 H 5 ) 2 SiO 2 / 2 T Vi :(CH=CH 2 )SiO 3 / 2 T: (CH 3 )SiO 3 / 2 T φ :(C 6 H 5 )SiO 3 / 2 Q:SiO 4 / 2 EP 1 : 3-glycidyloxypropyl group EP 2 : 8-glycidyloxyoctyl group

[0089] [Synthesis Example 1] 74.0g of vinyltrimethoxysilane, 117g of 3-glycidyloxypropyltrimethoxysilane and 16.5g of methanol were placed in a 500mL four-neck flask equipped with a stirrer, a cooling tube, a dropping funnel and a thermometer, and 2.4g of methanesulfonic acid was dropped while stirring. Then, 9.6g of water was dropped, mixed at 23°C for 30 minutes, and reacted at 70°C for 3 hours. Then, 28.8g of Kyoward (registered trademark) 500 (manufactured by Kyowa Chemical Industry Co., Ltd.) was added at 23°C and stirred for 3 hours, and Kyoward 500 was removed by filtration. Then, 5.7g of sodium bicarbonate was added, stirred at 60°C for 3 hours, and sodium bicarbonate was removed by filtration. Then, volatile components such as methanol were removed by vacuum concentration at 70°C to obtain a colorless transparent liquid polyorganosilsesquioxane (C-1). 29 From the Si-NMR and GPC (gel column chromatography) analyses, the structural unit ratio of polyorganosilsesquioxane (C-1) was [Ep 1 Si(OCH 3 ) 0.50 O 1.00 ] 0.58 [(CH=CH 2 )Si(OCH 3 ) 0.43 O 1.07 ] 0.42 and the amount of vinyl groups was 0.26 mol / 100 g.

[0090] [Synthesis Example 2] 22.2g of vinyltrimethoxysilane, 70.2g of 3-glycidyloxypropyltrimethoxysilane, 29.7g of phenyltrimethoxysilane and 12.2g of methanol were added to a 500mL four-neck flask equipped with a stirrer, a cooling tube, a dropping funnel and a thermometer, and 1.6g of methanesulfonic acid was added dropwise while stirring. Then, 13.3g of water was added dropwise, mixed at 23°C for 30 minutes, and then reacted at 70°C for 3 hours. Then, 18.6g of Kyoward (registered trademark) 500 (manufactured by Kyowa Chemical Industry Co., Ltd.) was added at 23°C and stirred for 3 hours, and Kyoward 500 was removed by filtration. Then, 3.7g of sodium bicarbonate was added, stirred at 60°C for 3 hours, and sodium bicarbonate was removed by filtration. Then, volatile components such as methanol were removed by vacuum concentration at 70°C to obtain a colorless transparent liquid polyorganosilsesquioxane (C-2). 29 From the Si-NMR and GPC analysis, the structural unit ratio of polyorganosilsesquioxane (C-2) was [Ep 1 Si(OCH 3 ) 0.46 O 1.04 ] 0.46 [(CH=CH 2 )Si(OCH 3 ) 0.45 O 1.05 ] 0.25 [(C 6 H 5 )Si(OCH 3 ) 0.49 O 1.01 ] 0.29 and the amount of vinyl groups was 0.13 mol / 100 g.

[0091] [Synthesis Example 3] 74.0g of vinyltrimethoxysilane, 117g of 8-glycidyloxyoctyltrimethoxysilane and 16.5g of methanol were placed in a 500mL four-neck flask equipped with a stirrer, a cooling tube, a dropping funnel and a thermometer, and 2.4g of methanesulfonic acid was dropped while stirring. Then, 9.6g of water was dropped, mixed at 23°C for 30 minutes, and reacted at 70°C for 3 hours. Then, 28.8g of Kyoward (registered trademark) 500 (manufactured by Kyowa Chemical Industry Co., Ltd.) was added at 23°C and stirred for 3 hours, and Kyoward 500 was removed by filtration. Then, 5.7g of sodium bicarbonate was added, stirred at 60°C for 3 hours, and sodium bicarbonate was removed by filtration. Then, volatile components such as methanol were removed by vacuum concentration at 70°C to obtain a colorless transparent liquid polyorganosilsesquioxane (C-3). 29 From the Si-NMR and GPC analyses, the structural unit ratio of polyorganosilsesquioxane (C-3) was [Ep 2 Si(OCH 3 ) 0.39 O 1.11 ] 0.45 [(CH=CH 2 )Si(OCH 3 ) 0.51 O 0.99 ] 0.55 and the amount of vinyl groups was 0.21 mol / 100 g.

[0092] [Comparative Synthesis Example 1] 224.4g of methyltrimethoxysilane, 389.9g of 3-glycidyloxypropyltrimethoxysilane and 61.3g of methanol were placed in a 1000mL four-neck flask equipped with a stirrer, a cooling tube, a dropping funnel and a thermometer, and 7.8g of methanesulfonic acid was dropped while stirring. Then, 47.7g of water was dropped, mixed at 23°C for 30 minutes, and reacted at 70°C for 3 hours. Then, 40.0g of Kyoward (registered trademark) 500 (manufactured by Kyowa Chemical Industry Co., Ltd.) was added at 23°C and stirred for 3 hours, and Kyoward 500 was removed by filtration. Then, 18.2g of sodium bicarbonate was added, stirred at 60°C for 3 hours, and sodium bicarbonate was removed by filtration. Then, volatile components such as methanol were removed by vacuum concentration at 70°C to obtain a colorless transparent liquid polyorganosilsesquioxane (C-4). 29 From the Si-NMR and GPC analyses, the structural unit ratio of polyorganosilsesquioxane (C-4) was [Ep 1 Si(OCH 3 ) 0.56 O 0.94 ] 0.51 [(CH 3 )Si(OCH 3 ) 0.61 O 0.89 ] 0.49 and the amount of vinyl groups was 0 mol / 100 g.

[0093] [Examples 1 to 4, Comparative Examples 1 to 3] The components listed below were mixed in the amounts shown in Table 1 to prepare an addition-curable silicone composition.

[0094] The numerical values ​​for each component in Table 1 represent parts by mass. The [Si-H] / [Si-Vi] value represents the ratio (molar ratio) of the number of hydrogen atoms (Si-H groups) bonded to silicon atoms in component (B) to the total number of alkenyl groups bonded to all silicon atoms in components (A), (C), and (E).

[0095] (A) Component: (A-1)M 3Vi 2 D 46 D 2φ 162A linear organopolysiloxane (viscosity at 25°C: 4600 mPa s, vinyl group content: 0.017 mol / 100 g)

[0096] (B) Ingredients: (B-1)M H 2 D 2φ 2 D H 2 A linear organohydrogenpolysiloxane represented by the formula (viscosity at 25°C: 21 mPa s, Si-H group content: 0.61 mol / 100 g).

[0097] (C) Ingredients: (C-1) Polyorganosilsesquioxane obtained in Synthesis Example 1 (C-2) Polyorganosilsesquioxane obtained in Synthesis Example 2 (C-3) Polyorganosilsesquioxane obtained in Synthesis Example 3 (C-4) Organopolysiloxane represented by the following structural formula: [ka] (C-5) Polyorganosilsesquioxane obtained in Comparative Synthesis Example 1

[0098] (D) Ingredients: (D-1) The reaction product of hexachloroplatinic acid and 1,3-divinyltetramethyldisiloxane is called M Vi 2 D 40 D 2φ 40 The catalyst (platinum concentration 0.004 mass%) was diluted with organopolysiloxane (viscosity 60 mPa s) represented by the formula

[0099] (E) Ingredients: (E-1) The composition unit ratio is M 0.3 M Vi 0.1 D 2φ 0.45 Q 0.15 The vinyl group content is 0.11 mol / 100 g, and the organopolysiloxane is a solid at 25° C.

[0100] (F) Ingredients: (F-1) 1-ethynylcyclohexanol (reaction regulator)

[0101] [Table 1]

[0102] The addition-curable silicone resin compositions obtained in Examples 1 to 4 and Comparative Examples 1 to 3 were evaluated as follows. The results are shown in Table 2.

[0103] [hardness] The composition was poured into a mold to a thickness of 2 mm, and cured at 150°C for 2 hours. The Type A hardness of the cured product was measured in accordance with JIS K6253-3:2012.

[0104] [Shear Adhesion Strength and Failure Mode] The composition was sandwiched between two aluminum substrates to a size of 10 mm x 15 mm x 2 mm, and cured at 150°C for 2 hours to prepare test pieces, whose shear adhesive strength was measured in accordance with JIS K6850:1999. In addition, the state of the interface between the cured product and the aluminum substrate after the test was visually observed to confirm the failure mode. When the cured product was found to have undergone cohesive failure, it was recorded as "cohesive failure", and when the cured product did not remain on the aluminum substrate after the test, it was recorded as "interface peeling".

[0105] [Durability] The composition was potted on an SMD3020 (manufactured by I-CHIUN PRECISION INDUSTRY) LED package and cured under the conditions of 150°C x 2 hours. The obtained sealed package was left to stand for 24 hours under the conditions of 85°C / 85%RH, and then the durability was evaluated by a thermal shock test. Specifically, the obtained sealed package was exposed to a 260°C environment for 30 seconds, and then cooled in a 25°C environment for 5 minutes. This process was repeated three times, and the peeling state of the interface between the cured product and the package was confirmed with an optical microscope. The number of tests was 6, and the durability was evaluated by counting the number of peeled pieces.

[0106] [Table 2]

[0107] As shown in Table 2, the cured products made from the addition-curable silicone compositions of Examples 1 to 4 of the present invention had high adhesive strength and showed good peeling mode (cohesive failure). In addition, no peeling from the LED package was observed after the thermal shock test, demonstrating their reliability as sealing materials.

[0108] On the other hand, the cured product obtained from the composition of Comparative Example 1 not containing component (C) had low adhesive strength, and as a result, all of the LED packages peeled off after the thermal shock test.

[0109] In Comparative Example 2, in which component (C) was changed to a cyclic organopolysiloxane containing neither T units nor alkenyl groups, the initial adhesive strength was high, but the durability to thermal shock was insufficient.

[0110] In Comparative Example 3, in which component (C) was changed to a polyorganosilsesquioxane containing no alkenyl groups, the results were inferior in adhesive strength and durability against thermal shock.

[0111] From the above results, it is clear that the addition-curable silicone resin composition of the present invention can provide a cured product having high adhesion and high thermal shock resistance, and an optical semiconductor device in which an optical semiconductor element is encapsulated with the cured product.

[0112] The present invention includes the following inventions.

[0113] [1]: (A) a linear organopolysiloxane having two or more alkenyl groups bonded to silicon atoms in each molecule; (B) an organohydrogenpolysiloxane having two or more hydrogen atoms bonded to silicon atoms in one molecule and having no aliphatic unsaturated bonds; (C) a polyorganosilsesquioxane having, per molecule, one or more alkenyl groups bonded to silicon atoms, one or more alkoxy groups bonded to silicon atoms, and one or more epoxy-containing groups bonded to silicon atoms; and (D)Platinum group metal catalyst An addition-curable silicone resin composition comprising:

[0114] [2]: The addition-curable silicone resin composition according to the above [1], wherein the component (A) is a linear organopolysiloxane represented by the following general formula (1): [ka] (In the formula, R 1 are independently a methyl group, a phenyl group, or a vinyl group, a is a number from 1 to 200, and b is a number from 0 to 100. The siloxane units in the parentheses to which a has been added and the siloxane units in the parentheses to which b has been added may be arranged randomly, in blocks, or alternately.

[0115] [3]: The addition-curable silicone resin composition according to the above [1] or [2], wherein the component (B) is a linear organohydrogenpolysiloxane represented by the following general formula (2): [ka] (In the formula, R 2 are independently a methyl group or a phenyl group, c is a number from 1 to 10, and d is a number from 0 to 10. The siloxane units in the parentheses to which c has been added and the siloxane units in the parentheses to which d has been added may be arranged randomly, in blocks, or alternately.

[0116] [4] The addition-curable silicone resin composition according to any one of the above [1] to [3], wherein the component (C) is a polyorganosilsesquioxane represented by the following formula (3): [R 3 Si(OR6 ) h O 1.5-h ] e [R 4 Si(OR 6 ) i O 1.5-i ] f [R 5 Si(OR 6 ) j O 1.5-j ] g (3) (In the formula, R 3 are independently a methyl group or a phenyl group, R 4 is a vinyl group, and R 5 is an alkyl group having 3 to 8 carbon atoms substituted with a glycidyloxy group, and R 6 are independently a methyl group or an ethyl group, e, f, and g are numbers that satisfy e≧0, f>0, g>0, and e+f+g=1, and h, i, and j are numbers that satisfy 0≦h≦1.5, 0≦i≦1.5, 0≦j≦1.5, and h+i+j>0.

[0117] [5] The addition-curable silicone resin composition according to any one of the above [1] to [4], further comprising, as component (E), a branched organopolysiloxane having an alkenyl group bonded to a silicon atom.

[0118] [6] A cured product, characterized in that it is obtained by curing the addition-curable silicone resin composition described in any one of [1] to [5] above.

[0119] [7] An optical semiconductor device, comprising an optical semiconductor element encapsulated with the cured product according to [6] above.

[0120] The present invention is not limited to the above-described embodiment. The above-described embodiment is merely an example, and anything that has substantially the same configuration as the technical idea described in the claims of the present invention and exhibits similar effects is included in the technical scope of the present invention.

Claims

1. (A) a linear organopolysiloxane having two or more alkenyl groups bonded to silicon atoms in each molecule; (B) an organohydrogenpolysiloxane having two or more hydrogen atoms bonded to silicon atoms in each molecule and having no aliphatic unsaturated bonds; (C) a polyorganosilsesquioxane having, per molecule, one or more alkenyl groups bonded to silicon atoms, one or more alkoxy groups bonded to silicon atoms, and one or more epoxy-containing groups bonded to silicon atoms; and (D) Platinum group metal catalyst An addition-curable silicone resin composition comprising:

2. 2. The addition-curable silicone resin composition according to claim 1, wherein the component (A) is a linear organopolysiloxane represented by the following general formula (1): 【Chemistry 1】 (In the formula, R １ are independently a methyl group, a phenyl group, or a vinyl group, a is a number from 1 to 200, and b is a number from 0 to 100. The siloxane units in the parentheses to which a is added and the siloxane units in the parentheses to which b is added may be arranged randomly, in blocks, or alternately.

3. 2. The addition-curable silicone resin composition according to claim 1, wherein the component (B) is a linear organohydrogenpolysiloxane represented by the following general formula (2): 【Chemistry 2】 (In the formula, R ２ are independently a methyl group or a phenyl group, c is a number from 1 to 10, and d is a number from 0 to 10. The siloxane units in the parentheses to which c is attached and the siloxane units in the parentheses to which d is attached may be arranged randomly, in blocks, or alternately.

4. 2. The addition-curable silicone resin composition according to claim 1, wherein the component (C) is a polyorganosilsesquioxane represented by the following formula (3): [R ３ Si(OR ６ ) ｈ O １．５－ｈ ] ｅ [R ４ Si(OR ６ ) ｉ O １．５－ｉ ] ｆ [R ５ Si(OR ６ ) ｊ O １．５－ｊ ] ｇ (3) (In the formula, R ３ are independently a methyl group or a phenyl group, R ４ is a vinyl group, R ５ is an alkyl group having 3 to 8 carbon atoms substituted with a glycidyloxy group, R ６ are independently a methyl group or an ethyl group, e, f, and g are numbers that satisfy e≧0, f>0, g>0, and e+f+g=1, and h, i, and j are numbers that satisfy 0≦h≦1.5, 0≦i≦1.5, 0≦j≦1.5, and h+i+j>0.

5. 2. The addition-curable silicone resin composition according to claim 1, further comprising, as component (E), a branched organopolysiloxane having an alkenyl group bonded to a silicon atom.

6. A cured product, which is obtained by curing the addition-curable silicone resin composition according to any one of claims 1 to 5.

7. An optical semiconductor device, comprising an optical semiconductor element encapsulated with the cured product according to claim 6.

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