JP2008280534A - Resin composition for sealing optic-related device, its cured product, and sealing method of semiconductor element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin composition for sealing optic-related devices which can form a coating film excellent in heat-resistance, ultraviolet resistance, optical transparency, tenacity and adhesion, and is thus useful for sealing optic-related devices. <P>SOLUTION: The resin composition for sealing optic-related devices comprises (i) a silylated organopolysiloxane having a weight-average molecular weight of 3×10<SP>4</SP>-50×10<SP>4</SP>in terms of polystyrene, (ii) a condensation catalyst and (iii) a solvent. The silylated organopolysiloxane (A) is represented by the average composition formula (1). R<SP>1</SP><SB>a</SB>(OX)<SB>b</SB>SiO<SB>(4-a-b)/2</SB>äwherein R<SP>1</SP>is alkyl group, alkenyl group or aryl group; X is a combination of a group represented by the formula -SiR<SP>2</SP>R<SP>3</SP>R<SP>4</SP>(wherein R<SP>2</SP>, R<SP>3</SP>and R<SP>4</SP>are each monovalent hydrocarbon group) and one or more groups selected from alkyl group, alkenyl group, alkoxy alkyl group or acyl group; a is a number of 1.00-1.5; b is a number larger than 0 and smaller than 1.5, provided that (a+b) is a number larger than 1.00 and smaller than 2}. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an optical material, and more specifically, for sealing light-related devices such as LED elements having high heat resistance and ultraviolet resistance, high optical transparency, and higher toughness. The present invention relates to a resin composition, a cured product thereof, and a semiconductor element sealing method using the composition.

  As sealing materials for light-related devices such as LED elements, highly transparent epoxy resins and silicone resins are widely used because of their workability and ease of handling. Recently, LEDs having a short wavelength, such as blue LEDs and ultraviolet LEDs, have been developed and their applications are rapidly expanding (for example, Patent Document 1). Under such circumstances, conventional epoxy resins and silicone resins have problems such as yellowing of the resin due to strong ultraviolet light and, in extreme cases, the resin skeleton being cut, making it difficult to use. Yes. In particular, sealing with resin is difficult for ultraviolet LED applications, and it is currently necessary to rely on glass sealing.

Therefore, development of a resin composition having excellent optical transparency and ultraviolet resistance is expected, while maintaining the excellent heat resistance, toughness and adhesiveness required for the sealing material, and further eliminating the above problems. ing.
JP 2001-207019 A

  In view of the above circumstances, the present invention can form a film or the like having excellent heat resistance, ultraviolet resistance, optical transparency, toughness and adhesiveness by curing, and sealing light-related devices such as LED elements. It aims at providing the curable resin composition useful for a stop.

In order to solve the above problems, the present inventors have made the present invention as a result of intensive studies. That is, the present invention firstly
(I) The following average composition formula (1):
R ¹ _a (OX) _b SiO _{(4-ab) / 2} (1)
Wherein R ¹ is independently an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms;
X represents a group represented by the formula: —SiR ² R ³ R ⁴ (wherein R ² , R ³ and R ⁴ are each independently an unsubstituted or substituted monovalent hydrocarbon group), and a carbon atom In combination with an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkoxyalkyl group having 2 to 6 carbon atoms or an acyl group having 2 to 6 carbon atoms, or a combination of two or more of these groups Yes;
a is a number from 1.00 to 1.5;
b is a number satisfying 0 <b <1.5;
However, a + b is 1.00 <a + b <2. )
A silylated organopolysiloxane having a polystyrene-equivalent weight average molecular weight of 3 × 10 ⁴ to 50 × 10 ⁴ represented by:
(B) a condensation catalyst, and
(C) A resin composition for sealing an optical device containing a solvent is provided.

  Secondly, the present invention provides a transparent cured product obtained by curing the composition.

  Thirdly, the present invention provides a method for encapsulating a semiconductor element, which comprises applying the composition to a semiconductor element and curing the composition applied to the semiconductor element.

  Fourthly, the present invention provides a resin-encapsulated semiconductor device comprising a semiconductor element and a cured product of the above composition that encapsulates the semiconductor element.

  The composition of the present invention is excellent in heat resistance, ultraviolet resistance, optical transparency, toughness and adhesiveness, and is useful for producing a cured product having a small birefringence. Moreover, the composition of the present invention is remarkably excellent in storage stability. Therefore, it is particularly useful for sealing light-related devices such as LED elements. Furthermore, when a semiconductor element is encapsulated by an encapsulating method using the composition of the present invention, for example, a light-related device having the above-described excellent characteristics can be produced.

  Hereinafter, the present invention will be described in detail. In the present specification, “room temperature” means 24 ± 2 ° C. Further, “polystyrene equivalent weight average molecular weight” means a polystyrene equivalent weight average molecular weight obtained from a molecular weight distribution obtained by gel permeation chromatography analysis (GPC).

<Resin composition>
The composition of the present invention comprises (a) component, (b) component, and (c) component. Hereafter, the component mix | blended with the composition of this invention is explained in full detail.

[(I) Silylated organopolysiloxane]
The component (a) has a polystyrene-reduced weight average molecular weight of 3 × 10 ⁴ to 50 × 10 ⁴ , typically 3 × 10 ^{4 to} 5 × 10 ⁴ , represented by the above average composition formula (1). Silylated organopolysiloxanes that are typically 3 × 10 ^{4 to} 4.5 × 10 ⁴ . When the weight average molecular weight is less than 3 × 10 ⁴ , cracks are easily formed when a high molecular weight organopolysiloxane is mixed with a condensation catalyst described later to produce a film, and a film having a thickness of 10 μm or more cannot be obtained. In some cases, when it exceeds 50 × 10 ⁴ , there is a problem that the adhesiveness is remarkably lowered.

In the average composition formula (1), examples of the alkyl group having 1 to 6 carbon atoms represented by R ¹ include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, and an isobutyl group. Examples of the alkenyl group having 2 to 6 carbon atoms include an allyl group and a vinyl group. Examples of the aryl group having 6 to 12 carbon atoms include a phenyl group, a tolyl group, a xylyl group, and a naphthyl group. Etc. R ¹ is particularly preferably a methyl group.

In the above average composition formula (1), R ² , R ³ and R ⁴ are independently a non-reactive substituted or unsubstituted monovalent hydrocarbon group, preferably having 1 to 6 carbon atoms, more preferably Are 1-3. Specifically, alkyl groups such as methyl, ethyl and propyl groups, alkenyl groups such as allyl groups and vinyl groups, aryl groups such as phenyl groups, and some or all of the hydrogen atoms of these groups are halogen-substituted. The thing etc. are illustrated. In addition, the alkyl group, alkenyl group, alkoxyalkyl group and acyl group represented by X each have the aforementioned number of carbon atoms. Examples of the alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, and an isobutyl group. Examples of the alkenyl group having 2 to 6 carbon atoms include allyl group and vinyl group. Examples of the alkoxyalkyl group having 2 to 6 carbon atoms include a methoxyethyl group, an ethoxyethyl group, and a butoxyethyl group. Examples of the acyl group having 2 to 6 carbon atoms include an acetyl group and a propionyl group.

In the average composition formula (1), represented by X [formula: -SiR ² R ³ R ⁴ (wherein R ² , R ³ and R ⁴ are as described above]) : [The above-mentioned alkyl group, alkenyl group, alkoxyalkyl group or acyl group or two or more of these groups] is preferably 1: 1 to 8: 1 in molar ratio, and 2: 1 to 4: 1. Is more preferable. When this range is satisfied, a composition having excellent curability is obtained, and the cured product obtained by further curing has film properties such as good adhesiveness.

  In the average composition formula (1), a is a number of 1.00 to 1.5, preferably 1.05 to 1.3, particularly preferably 1.1 to 1.2, and b is a number satisfying 0 <b <1.5, preferably Is a number from 0.01 to 1.0, particularly preferably from 0.05 to 0.3. When a is less than 1.00, the film may be easily cracked, and when it exceeds 1.5, the film may have low toughness and easily become brittle. When b is 0, the adhesion of the film to the substrate (for example, a semiconductor element) may be inferior, and when it exceeds 1.5, a cured film may not be obtained. Further, a + b is a number satisfying 1.00 <a + b <2, preferably 1.00 to 1.5, particularly preferably 1.1 to 1.3.

In order for the silylated organopolysiloxane of component (a) to be more excellent in the heat resistance of the resulting cured product, the ratio of R ¹ typified by methyl groups and the like in the silylated organopolysiloxane ( (Based on mass) is preferably reduced. Specifically, it is preferably 32% by mass or less, typically 15 to 30% by mass, and more typically 20 to 27% by mass. Moreover, the silylated organopolysiloxane of component (a) may be used alone or in combination of two or more. In addition, when the silylated organopolysiloxane of component (a) is applied to uses such as UV ultraviolet irradiation, deterioration due to UV increases if the molecule contains an aryl group such as a phenyl group. There is a case. Therefore, R ¹ and X in the average composition formula (1) or R ⁵ and R ^{6 in} the general formula (2) described later are preferably other than an aryl group such as a phenyl group.

-Manufacturing method-
The component (i) silylated organopolysiloxane may be produced by any method. For example, it can be produced by silylating an organopolysiloxane obtained by ordinary hydrolysis condensation. it can.

Method for producing organopolysiloxane subjected to silylation Specifically, the organopolysiloxane subjected to silylation is, for example, a silane compound having a hydrolyzable group, preferably the following general formula (2):
SiR ⁵ _c (OR ⁶ ) _4-c (2)
Wherein R ⁵ is independently the same as R ¹ defined above, and R ⁶ is independently the group represented by the formula: —SiR ² R ³ R ⁴ out of X defined above. Same as above (that is, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkoxyalkyl group having 2 to 6 carbon atoms, or an acyl group having 2 to 6 carbon atoms) C is an integer of 0 to 3.)
A silane compound (c = 1 to 3) and a silicate (c = 0), and a polycondensate of the silicate (that is, a polysilicate) (hereinafter, “(poly) silicate” is a combination of a silicate and a polysilicate). Obtained by hydrolysis and condensation. The silane compound having a hydrolyzable group is preferably only the silane compound (c = 1 to 3) represented by the general formula (2), but the silane compound represented by the general formula (2) ( A combination of c = 1 to 3) and the above (poly) silicate may be used. These silane compounds and (poly) silicates represented by the general formula (2) may be used alone or in combination of two or more.

  Examples of the silane compound represented by the general formula (2) include organotrimethylsilanes such as methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, phenyltrimethoxysilane, and phenyltriethoxysilane. Alkoxysilanes; Diorganodialkoxysilanes such as dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, methylphenyldimethoxysilane, methylphenyldiethoxysilane; trimethylmethoxysilane, trimethylethoxysilane, triethylmethoxysilane , Triorganoalkoxysilanes such as triethylethoxysilane, triphenylmethoxysilane, and triphenylethoxysilane.

Examples of the silicate represented by the general formula (2) include tetraalkoxysilanes (namely, alkyl silicates) such as tetramethoxysilane, tetraethoxysilane, and tetraisopropyloxysilane.
Preferred as the silane compound (c = 1 to 3) or silicate (c = 0) represented by the general formula (2) are methyltrimethoxysilane and dimethyldimethoxysilane. Examples of the polysilicate include polycondensates of alkyl silicate (alkyl polysilicate) such as methyl polysilicate and ethyl polysilicate.

  The silane compound having a hydrolyzable group is a silane compound having three hydrolyzable groups in one molecule (that is, in the case of the silane compound represented by the general formula (2), c = 1 ) In a total amount of 50 mol% or more (50 to 100 mol%), particularly 70 to 95 mol%, particularly 75 to 85 mol%. Specific examples of the silane compound having three hydrolyzable groups in one molecule include organotrihydrocarbyloxysilanes such as the above organotrialkoxysilanes. The silane compound having three hydrolyzable groups in one molecule is particularly preferably an organotrialkoxysilane.

  In particular, in order to obtain a cured product having excellent crack resistance and heat resistance, the organopolysiloxane subjected to the silylation is composed of 50 to 100 mol% of organotrialkoxysilane such as methyltrimethoxysilane and dimethyldimethoxysilane. Are preferably composed of 50 to 0 mol% of diorganodialkoxysilane, 75 to 85 mol% of organotrialkoxysilane such as methyltrimethoxysilane, and 25 to 15 mol% of diorganodialkoxysilane such as dimethyldimethoxysilane More preferably, it consists of

-Method for producing organopolysiloxane subjected to silylation (preferred embodiment)
In a preferred embodiment, the organopolysiloxane to be subjected to the silylation can be obtained by subjecting a silane compound having a hydrolyzable group to a two-stage hydrolysis condensation reaction of a primary hydrolysis condensation and a secondary hydrolysis condensation. . For example, the following conditions can be applied.

Specifically, for example,
(i) a step of obtaining a organopolysiloxane by subjecting a silane compound having a hydrolyzable group to primary hydrolysis and condensation (step (i));
(ii) a step of subjecting the organopolysiloxane to further secondary hydrolysis and condensation (step (ii));
It is preferable to manufacture by the method containing.

  The details of the silane compound having a hydrolyzable group used as a starting material in the step (i) are as described and exemplified above as the silane compound having a hydrolyzable group.

  The hydrolysis and condensation of the silane compound having a hydrolyzable group in step (i) may be carried out by a usual method, but it is preferably carried out in the presence of an acid catalyst such as acetic acid, hydrochloric acid, sulfuric acid and the like. When the acid catalyst is used, the amount used can be, for example, about 0.0001 to 0.01 mol, preferably about 0.0005 to 0.005 mol per mol of the total hydrolyzable groups in the silane compound having a hydrolyzable group. . When the amount used satisfies the above range, a desired hydrolysis-condensation product having an appropriate molecular weight can be obtained.

  The amount of water added during the hydrolysis and condensation in step (i) is the total amount of hydrolyzable groups (usually hydrocarbyloxy groups such as alkoxy groups) in the silane compound having the hydrolyzable group. The amount is usually 0.9 to 1.5 mol, preferably 1.0 to 1.2 mol per mol. When this addition amount satisfies the range of 0.9 to 1.5 mol, the composition has excellent workability, and the cured product has excellent toughness.

  The silane compound having a hydrolyzable group is usually preferably used after being dissolved in an organic solvent such as alcohols, ketones, esters, cellosolves, aromatic compounds and the like. Specifically, as the organic solvent, for example, alcohols such as methanol, ethanol, isopropyl alcohol, isobutyl alcohol, n-butanol, and 2-butanol are preferable, and the curability of the composition and the toughness of the cured product are excellent. Isobutyl alcohol is more preferable at the point which becomes thing.

  The reaction temperature for hydrolysis and condensation in step (i) is preferably 40 to 120 ° C, more preferably 60 to 80 ° C. When the reaction temperature satisfies such a range, a hydrolytic condensate having a molecular weight that can be used in the next step is obtained without gelation.

Thus, the desired organopolysiloxane is obtained in step (i). This organopolysiloxane can be obtained in the form of a solution when the above organic solvent is used. The organopolysiloxane may be used in the step (ii) in a solution state or may be used in the step (ii) after distilling off the solvent to obtain only a non-volatile content. The volatile content of the solvent and the like is preferably 5% by mass or more, and more preferably 10 to 35% by mass. If the volatile content is less than 5% by mass, the organopolysiloxane may be easily gelled, and if it exceeds 35% by mass, the reactivity may be lowered.
The weight average molecular weight in terms of polystyrene of the organopolysiloxane obtained in step (i) is preferably 5 × 10 ³ to 2 × 10 ⁴ , more preferably 1 × 10 ⁴ to 2 × 10 ⁴ , particularly preferably 1 × 10. ^{4 to} 1.5 × 10 ⁴ . When such a range is satisfied, in step (ii), the organopolysiloxane is easily increased in molecular weight, and the desired appropriate high molecular weight organopolysiloxane can be obtained.

  In step (ii), the organopolysiloxane obtained in step (i) is further subjected to secondary hydrolysis and condensation.

  This secondary hydrolysis and condensation is preferably carried out in the presence of an anion exchange resin as a hydrolysis condensation catalyst. As this anion exchange resin, a polystyrene-based anion exchange resin is preferable. This anion exchange resin may be used individually by 1 type, or may use 2 or more types together. As the polystyrene-based anion exchange resin, Diaion (manufactured by Mitsubishi Chemical Corporation) is preferably used under the trade name. Specific product names include Diaion SA Series (SA10A, SA11A, SA12A, NSA100, SA20A, SA21A), Diaion PA Series (PA308, PA312, PA316, PA406, PA412, PA418), Diaion Examples thereof include HPA series (HPA25), Diaion WA series (WA10, WA20, WA21J, WA30).

  Among the anion exchange resins, the following structural formula (3):

（３）
で表される分子構造を有する水分含有系のポリスチレン系陰イオン交換樹脂が好ましく、この樹脂中に30〜70質量％、とりわけ40〜50質量％の水分を含有するポリスチレン系陰イオン交換樹脂が特に好ましい。上記具体例のうち、SA10Aは上記構造式（３）で表される分子構造を有し、樹脂中に43〜47質量％の水分を含有するポリスチレン系陰イオン交換樹脂であるので、特に好適に使用される。水分含有系のポリスチレン系陰イオン交換樹脂等の陰イオン交換樹脂を用いた場合には、該触媒中の水分が作用して反応が進行する。なお、水分含有系のポリスチレン系陰イオン交換樹脂とは、最も一般的には、ゲル型のイオン交換樹脂であり、該樹脂粒子内部が均一な架橋高分子で構成されているもので、透明感のある外観を有する。該樹脂粒子の内部は橋架けされた高分子が均一な網目状の構造となっており、この網目の隙間を通って水分等が粒子内部まで自由に拡散しているものである。水分含有系の陰イオン交換樹脂を用いない場合には、別途、水を添加する必要がある。その際の水の使用量は、樹脂中に30〜70質量％の割合となるように添加することが好ましく、水がない場合や少なすぎる場合には陰イオン交換樹脂の塩基性が弱くなり、反応性が低下する場合がある。上記適切な割合の水分が存在することによって該陰イオン交換樹脂の塩基性が強くなり、反応が良好に進行する。

(3)
A water-containing polystyrene-type anion exchange resin having a molecular structure represented by the formula is preferred, and a polystyrene-type anion exchange resin containing 30-70% by mass, particularly 40-50% by mass of water in this resin is particularly preferred. preferable. Among the above specific examples, SA10A is a polystyrene-based anion exchange resin having a molecular structure represented by the structural formula (3) and containing 43 to 47% by mass of water in the resin. used. When an anion exchange resin such as a moisture-containing polystyrene-based anion exchange resin is used, the water in the catalyst acts and the reaction proceeds. The water-containing polystyrene-based anion exchange resin is most commonly a gel-type ion exchange resin, and the inside of the resin particles is composed of a uniform crosslinked polymer. It has a certain appearance. The inside of the resin particles has a network structure in which the crosslinked polymer is uniform, and moisture and the like are freely diffused to the inside of the particles through the gaps of the network. When a water-containing anion exchange resin is not used, it is necessary to add water separately. The amount of water used at that time is preferably added so as to be a proportion of 30 to 70% by mass in the resin, and when there is no water or too little water, the basicity of the anion exchange resin becomes weak, The reactivity may decrease. The presence of the appropriate proportion of moisture increases the basicity of the anion exchange resin, and the reaction proceeds well.

  The amount of the anion exchange resin used is usually 1 to 50% by mass, preferably 5 to 30% by mass, based on the non-volatile content of the organopolysiloxane that is the starting material in step (ii). When this range is satisfied, the reaction rate of hydrolysis and condensation in step (ii) is good, and a more stable organopolysiloxane to be subjected to silylation can be obtained.

  The reaction temperature for hydrolysis and condensation in step (ii) is preferably 10 to 60 ° C, and the reaction proceeds more favorably when it is particularly 25 to 45 ° C. When the reaction temperature is within such a range, the reaction rate is good and a more stable organopolysiloxane to be subjected to silylation can be obtained.

  The hydrolysis and condensation in step (ii) is preferably performed in a solvent, and the concentration of the organic solid component is preferably 50 to 95% by mass, particularly 65 to 90% by mass. When this range is satisfied, a reaction rate is good and a more stable organopolysiloxane to be subjected to silylation can be obtained.

  The solvent in the step (ii) is not particularly limited, but preferably has a boiling point of 64 ° C. or higher. Examples of the solvent include hydrocarbon solvents such as benzene, toluene and xylene; ether solvents such as tetrahydrofuran, 1,4-dioxane and diethyl ether; ketone solvents such as methyl ethyl ketone; chloroform, methylene chloride and 1,2- Halogen solvents such as dichloroethane; alcohol solvents such as methanol, ethanol, isopropyl alcohol, isobutyl alcohol; octamethylcyclotetrasiloxane, hexamethyldisiloxane, etc., and cellosolve acetate, cyclohexanone, butyrocellosolve, methylcarbitol , Carbitol, butyl carbitol, diethyl carbitol, cyclohexanol, diglyme, triglyme and the like organic solvents having a boiling point of 150 ° C. or more, preferably xylene, isobutyl Alcohol, bis (2-methoxyethyl) d - ether, triglyme, particularly preferably isobutyl alcohol. These solvents may be used alone or in combination of two or more.

Thus, the organopolysiloxane to be subjected to the above-mentioned silylation intended for the step (ii) is obtained. The organopolysiloxane to be subjected to silylation obtained here preferably has a polystyrene-equivalent weight average molecular weight of 3 × 10 ⁴ or more. When the hydrolysis and condensation in the step (ii) are performed in a solvent, the organopolysiloxane subjected to the silylation is obtained in a solution state. The organopolysiloxane may be subjected to silylation in a solution state or may be subjected to silylation after distilling off the solvent to obtain only a non-volatile content. However, in the absence of a solvent, the organopolysiloxane tends to gel easily, so that it is preferably stored in a solution state from the viewpoint of storage stability. It is more preferable to store at a temperature of

Silylation of organopolysiloxane The organopolysiloxane to be subjected to silylation obtained by any of the above methods has a high molecular weight, and therefore easily gels due to condensation of the remaining hydroxyl groups. Therefore, the hydroxyl group remaining in the organopolysiloxane can be stabilized by silylation (that is, silylation reaction). The reaction temperature of this silylation reaction is usually 0 to 150 ° C., preferably 0 to 60 ° C.

  Examples of the silylation reaction method include a method in which the organopolysiloxane is reacted with a compound having a silyl group bonded to a non-reactive substituent. Specifically, a method of reacting the organopolysiloxane with a trialkylhalosilane; hexaalkyldisilazane, N, N-diethylaminotrialkylsilane, N- (trialkylsilyl) acetamide, N-methyl (trialkylsilyl) A method using a nitrogen-containing silylating agent such as acetamide, N, O-bis (trialkylsilyl) acetamide, N, O-bis (trialkylsilyl) carbamate, N-trialkylsilylimidazole; Examples include a method of reacting with silanol; a method of reacting the organopolysiloxane with hexaalkyldisiloxane under weak acidity, and the like. When trialkylhalosilane is used, a by-product hydrogen halide may be neutralized in the presence of a base. When a nitrogen-containing silylating agent is used, a catalyst such as trimethylchlorosilane or ammonium sulfate may be added. Specifically, a method of using trimethylchlorosilane as a silylating agent in the presence of triethylamine is preferable.

  These silylation reactions may be performed in a solvent, but may be performed without using a solvent. When using a solvent, for example, aromatic hydrocarbon solvents such as benzene, toluene, xylene; aliphatic hydrocarbon solvents such as hexane and heptane; ether solvents such as diethyl ether and tetrahydrofuran; ketones such as acetone and methyl ethyl ketone System solvents; ester solvents such as ethyl acetate and butyl acetate; halogenated hydrocarbon solvents such as chloroform, trichloroethylene and carbon tetrachloride; dimethylformamide; dimethyl sulfoxide and the like can be used.

Thus, the silylated organopolysiloxane represented by the above average composition formula (1) and having a polystyrene-equivalent weight average molecular weight of 3 × 10 ⁴ or more is obtained. When the silylation reaction is carried out in a solvent, the silylated organopolysiloxane can be obtained in the form of a solution, but it can be stored and used in the form of a solution, or the solvent can be distilled off to obtain only non-volatile content. May be stored and used.

[(B) Condensation catalyst]
The (b) component condensation catalyst is a component required to cure the silylated organopolysiloxane of component (a). The condensation catalyst is not particularly limited, and an organometallic catalyst, a Lewis acid or an aluminum compound can be used. From the viewpoint of excellent stability of the silylated organopolysiloxane and the resulting cured product being excellent in hardness, non-yellowing property, etc., an organometallic catalyst is usually used. Examples of the organometallic catalyst include those containing metal atoms such as zinc, aluminum, titanium, tin, and cobalt. Preferably, tin, zinc, aluminum, or titanium atoms, or these atoms are used. What contains 1 type or 2 or more types of combinations is mentioned. More specifically, as an organic metal catalyst, for example, an organic acid zinc, an organic aluminum compound, an organic titanium compound, an organic acid tin compound, an organic acid cobalt compound, etc. are preferably used, and in particular, zinc octylate, zinc benzoate. , Zinc p-tert-butylbenzoate, zinc laurate, zinc stearate, aluminum triisopropoxide, aluminum acetylacetonate, aluminum monoacetylacetonate bis (ethylacetoacetate), aluminum butoxybisethylacetoacetate, tetrabutyl Examples include titanate, tetraisopropyl titanate, tin octylate, cobalt naphthenate, and tin naphthenate. Among these, aluminum monoacetylacetonate bis (ethyl acetoacetate) is preferably used. Specific examples of the Lewis acid that can be used as a condensation catalyst include boron fluoride (BF ₃ ), boron chloride (BCl ₃ ), and antimony fluoride (SbF ₃ , SbF ₅ ). Examples of the aluminum compound that can be used as a condensation catalyst include aluminum chloride, aluminum perchlorate, and aluminum phosphate.

  The addition amount of the condensation catalyst is usually 0.05 to 10 parts by mass, preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the silylated organopolysiloxane of component (a). When this range is satisfied, the curability of the composition is good and stable. The (b) component condensation catalyst may be used alone or in combination of two or more.

[(C) Solvent]
The solvent as component (c) has a uniform thickness and a smooth surface when the composition of the present invention is applied to the surface of a semiconductor element as a substrate and cured to form a film. It is effective in forming in a state (that is, in a large area).
As the solvent of component (c), an organic solvent having a boiling point of preferably 150 ° C. or higher, more preferably 155 to 230 ° C., particularly preferably 160 ° C. to 170 ° C. is used. Can also be mixed and used within a certain range.

  Examples of the organic solvent having a boiling point of 150 ° C. or higher include cellosolve acetate, cyclohexanone, butyl cellosolve, methyl carbitol, carbitol, butyl carbitol, diethyl carbitol, cyclohexanol, bis (2-methoxyethyl) ether, and triglyme. Among them, bis (2-methoxyethyl) ether is preferable.

  Examples of the organic solvent having a boiling point of less than 150 ° C. include hydrocarbon solvents such as benzene, toluene and xylene; ether solvents such as tetrahydrofuran, 1,4-dioxane and diethyl ether; ketone solvents such as methyl ethyl ketone; chloroform Halogenated hydrocarbon solvents such as methylene chloride and 1,2-dichloroethane (especially chlorinated hydrocarbon solvents); alcohol solvents such as methanol, ethanol, isopropyl alcohol and isobutyl alcohol; octamethylcyclotetrasiloxane, hexamethyl Examples thereof include siloxane solvents such as disiloxane.

  The organic solvent may be used singly or in combination of two or more. However, an organic solvent having a boiling point of less than 150 ° C. is usually used in the form of a mixed solvent with an organic solvent having a boiling point of 150 ° C. or more. In such a mixed solvent, the proportion of the organic solvent having a boiling point of less than 150 ° C. is preferably 30% by mass or less and the organic solvent having a boiling point of 150 ° C. or more is preferably 70% by mass or more.

  That is, generally, the solvent used as the component (c) is preferably composed of 70 to 100% by mass of an organic solvent having a boiling point of 150 ° C. or higher, more preferably 80 to 100% by mass, and 100% by mass. More preferably. Under such conditions, when the composition of the present invention is cured, generation of bubbles (voids) due to bubbles can be suppressed, and a uniform and excellent cured film can be formed. A molded product having good adhesion to the surface can be obtained.

  The compounding amount of the component (c) is preferably 50 parts by mass or less, more preferably 5 to 40 parts by mass, and particularly preferably 10 to 30 parts by mass with respect to 100 parts by mass of the component (b). That is, the content of the component (a) relative to the sum of the components (a) and (c) is preferably 67% by mass or more, more preferably 71 to 95% by mass, and particularly preferably 77 to 91% by mass. When such a range is satisfied, the moldability of the cured product becomes better, and the thickness of the cured product is typically 10 μm to 3 mm, more typically 20 μm to 1 mm in a dry state. It becomes easy to process.

[Other optional ingredients]
In the composition of the present invention, in addition to the components (a), (b), and (c), other optional components can be blended within a range that does not impair the effects and effects of the present invention. Other optional components include, for example, inorganic fillers, inorganic phosphors, anti-aging agents, radical inhibitors, ultraviolet absorbers, adhesion improvers, flame retardants, surfactants, storage stability improvers, ozone deterioration inhibitors. , Light stabilizer, thickener, plasticizer, coupling agent, antioxidant, heat stabilizer, conductivity imparting agent, antistatic agent, radiation blocking agent, nucleating agent, phosphorus peroxide decomposing agent, lubricant, Examples include pigments, metal deactivators, physical property modifiers, and organic solvents. These optional components may be used alone or in combination of two or more.

  When an inorganic filler is blended, there are effects such that the light scattering of the obtained cured product and the fluidity of the composition are in an appropriate range, and the material using the composition is increased in strength. The inorganic filler is not particularly limited, but is preferably in the form of fine particles that do not deteriorate the optical properties, such as alumina, aluminum hydroxide, fused silica, crystalline silica, ultrafine amorphous silica, hydrophobic ultrafine silica, talc. , Calcium carbonate, barium sulfate and the like.

Examples of inorganic phosphors include yttrium, aluminum, garnet-based YAG phosphors, ZnS phosphors, Y ₂ O ₂ S phosphors, red-emitting phosphors, and blue-emitting phosphors that are widely used in LEDs. Body, green light emitting phosphor and the like.

  In the simplest embodiment, the composition of the present invention is a composition containing the component (a), the component (b), and the component (c) and not containing an inorganic filler such as a silica filler. It is a composition substantially consisting of only the component (a), the component (b), and the component (c). Here, “consisting essentially of only” means that the amount of the components other than (a), (b) and (c) is less than 5% by mass, preferably less than 3% by mass, particularly less than 3% by mass. Means less than 1% by weight.

(Preparation of composition)
The composition of the present invention can be prepared by mixing the component (a), the component (b), the component (c), and an optional component optionally contained by any method. Specifically, for example, (i) component, (b) component, (c) component and optional optional components are usually mixed with a commercially available stirrer (for example, THINKY CONDITIONING MIXER (manufactured by Shinky Co., Ltd.)). ) And uniformly mixing for about 1 to 5 minutes, the composition of the present invention can be prepared.

[Production of cured product]
A transparent cured product can be prepared by curing the composition. The thickness of the cured product is not particularly limited, but the lower limit is preferably 10 μm, particularly preferably 20 μm, and the upper limit is preferably 3 mm (3000 μm), particularly preferably 1 mm (1000 μm), typically 10 μm. ~ 3mm.

  As the curing condition, for example, the composition may be heated at 25 to 200 ° C. for about 1 to 12 hours, but cured in a plurality of stages at different temperatures in the range of 25 to 200 ° C. (ie, step cure). It is preferable. Step cure can be performed, for example, through two stages or three or more stages, and preferably through three stages described below. First, the composition is cured at a low temperature at 60 to 120 ° C. The curing time may be in the range of about 0.5 to 2 hours. Next, the low-temperature cured composition is heat-cured at 120 to 160 ° C. The curing time may be in the range of about 0.5 to 2 hours. Finally, the heat-cured composition is further heat-cured at 160 to 200 ° C. The curing time may be in the range of about 1 to 5 hours. More specifically, for example, the composition is preferably low-temperature cured at 80 ° C. for 0.5 hours, then heat-cured at 150 ° C. for 1 hour, and further heat-cured at 180 ° C. for 4 hours.

  By the curing process through these steps, the cured product has a good cured state, and the generation of bubbles is appropriately suppressed. Furthermore, a colorless and transparent cured product having the above thickness can be obtained by step cure. In particular, it is possible to produce a cured product having a thickness of 10 μm to 3 mm by including a step of heat curing at a temperature of 100 ° C. or higher. In addition, the step cure process causes the remaining silyl group, alkoxy group and the like to undergo a curing reaction in accordance with the difference in reactivity, so that the cured strain (internal stress) of the resulting cured product is reduced, which is preferable.

  A cured product obtained by curing the composition of the present invention has high strength and good flexibility and adhesiveness. Also, a thick film (for example, 50 μm or more) can be produced from the composition of the present invention.

  The glass transition point (Tg) of the cured product obtained by curing the composition of the present invention is usually a commercially available measuring instrument (for example, thermomechanical tester (trade name: TM-7000, manufactured by Vacuum Riko Co., Ltd.). In the range: 25 to 200 ° C.)), the cured product is extremely excellent in heat resistance.

[Use of composition]
The composition of the present invention is useful for sealing a light-related device such as an LED element, particularly for sealing a blue LED or an ultraviolet LED. The composition of the present invention has other properties such as excellent heat resistance, ultraviolet resistance, and transparency, so the following display materials, optical recording materials, optical equipment materials, optical component materials, optical fiber materials, It can also be used for applications such as optical / electronic functional organic materials and semiconductor integrated circuit peripheral materials.

-1. Display materials
Display materials include, for example, liquid crystal display substrate materials, light guide plates, prism sheets, deflector plates, retardation plates, viewing angle correction films, adhesives, liquid crystal display peripheral materials such as polarizer protective films, etc. ; Color plasma display (PDP) sealing material, next generation flat panel display, antireflection film, optical correction film, housing material, front glass protective film, front glass substitute material, adhesive, etc .; Plasma addressed liquid crystal (PALC) ) Display substrate material, light guide plate, prism sheet, deflection plate, retardation plate, viewing angle correction film, adhesive, polarizer protective film, etc .; protective film for front glass of organic EL (electroluminescence) display, substitute for front glass Materials, adhesives, etc .; field emission diss Various film substrate Ray (FED), front glass protective films, front glass substitute material, adhesives and the like.

-2. Optical recording material
Examples of optical recording materials include VD (video disc), CD, CD-ROM, CD-R / CD-RW, DVD ± R / DVD ± RW / DVD-RAM, MO, MD, PD (phase change disc). Or the disk substrate material for optical cards, a pickup lens, a protective film, a sealing material, an adhesive agent etc. are mentioned.

-3. Optical equipment materials
Optical equipment materials include, for example, steel camera lens materials, viewfinder prisms, target prisms, viewfinder covers, light receiving sensor sections, etc .; video camera shooting lenses, viewfinders, etc .; projection television projection lenses, protective films, sealing materials Adhesives, etc .; Lens materials for optical sensing devices, sealing materials, adhesives, films and the like.

-4. Optical component materials
Examples of optical component materials include fiber materials, lenses, waveguides, element sealing materials, and adhesives around optical switches in optical communication systems; optical fiber materials, ferrules, sealing materials, and adhesives around optical connectors. Etc .; Optical passive components / optical circuit components such as lenses, waveguides, LED element encapsulants, adhesives, etc .; Optoelectronic integrated circuit (OEIC) peripheral substrate materials, fiber materials, element encapsulants, adhesives, etc. Etc.

-5. Optical fiber materials
Examples of the optical fiber material include decoration display lighting / light guides, etc .; industrial sensors, displays / signs, etc .; optical fibers for communication infrastructure and home digital equipment connection.

-6. Peripheral materials for semiconductor integrated circuits
Examples of the semiconductor integrated circuit peripheral material include resist materials for microlithography for LSI and VLSI materials.

-7. Optical and electronic functional organic materials
Examples of optical / electronic functional organic materials include organic EL element peripheral materials; organic photorefractive elements; optical amplification elements that are light-to-light conversion devices, optical arithmetic elements, substrate materials around organic solar cells; fiber materials; Examples thereof include an element sealing material and an adhesive.

[Semiconductor element sealing method]
Semiconductor elements such as LED elements can be sealed using a cured product of the composition of the present invention. Specifically, for example, the sealing can be performed by a method including applying the composition to a semiconductor element and curing the composition applied to the semiconductor element. The application of the composition may be performed in a varnish state as the composition containing the organic solvent, but may be performed in a composition state not containing the organic solvent. Moreover, application | coating may be performed by coating or an immersion method, and a spin coat method, a roll coater method, a flow coater method, a knife coater method, a squeezing method, etc. can be applied. The applied composition can be cured using, for example, the above-described step cure process.

[Resin encapsulated semiconductor device]
The resin-encapsulated semiconductor device of the present invention has a semiconductor element and a cured product of the above composition that encapsulates the semiconductor element.

  Examples of the semiconductor element sealed with the cured product of the composition include a light emitting diode, a photodiode, a CCD, a CMOS, an image sensor, a phototransistor, an IR sensor, and a laser diode.

  The thickness of the cured product of the composition for sealing the semiconductor element can be 10 μm to 3 mm (3000 μm), and particularly preferably about 20 μm to 1 mm (1000 μm).

EXAMPLES Hereinafter, although this invention is demonstrated more concretely using an Example, this invention is not limited at all by these Examples. The methyltrimethoxysilane used in the synthesis example is KBM13 (trade name) manufactured by Shin-Etsu Chemical Co., Ltd., and dimethyldimethoxysilane is KBM22 (trade name) manufactured by Shin-Etsu Chemical Co., Ltd.
In addition, in the following description, “weight average molecular weight in terms of polystyrene” is a value obtained by measurement with a THF solution (0.6 ml / min) using a high-speed GPC device (trade name HLC-8220GPC) manufactured by Tosoh Corporation. It is.

<Synthesis Example 1>
A stirrer and a condenser tube were set in a 1 L three-necked flask. In this flask, 109 g (0.8 mol) of methyltrimethoxysilane, 24 g (0.2 mol) of dimethyldimethoxysilane and 106 g of isobutyl alcohol were placed and cooled with ice while stirring. While maintaining the temperature in the system at 0 ° C. to 20 ° C., 60.5 g of 0.05N hydrochloric acid solution was added dropwise. After completion of the dropwise addition, the obtained mixture was stirred at a reflux temperature of 80 ° C. for 11 hours. Next, the obtained reaction solution was cooled to room temperature, and then diluted with 150 g of xylene. Thereafter, the diluted reaction solution was put into a separating funnel and washed with 300 g of water, and washing was continued until the washing water conductivity after washing was 2.0 μS / cm or less. Then, water is distilled off by azeotropic dehydration of the washed reaction solution, the volatile content is adjusted to 30% by mass, and the following formula (4):
(CH ₃ ) _1.2 (OX) _0.25 SiO _1.28 (4)
(In the formula, X is a combination of hydrogen atom: methyl group: isobutyl group = 7.0: 1.0: 0.9 (molar ratio), and the hydrolysis rate is 91.1 mol%.)
113 g of an organopolysiloxane A solution having a weight average molecular weight in terms of polystyrene of 15000 represented by (including an organic solvent and having a nonvolatile content of 70% by mass) was obtained.

Next, 113 g of the obtained organopolysiloxane A solution (containing an organic solvent and having a nonvolatile content of 70% by mass) and a polystyrene-based anion exchange resin (trade name: Diaion SA10A, manufactured by Mitsubishi Chemical Corporation, moisture content) (Content: 43-47% by mass) 15.8 g was placed in a flask and stirred and mixed at 36 ° C. for 32 hours for reaction. After completion of the reaction for 32 hours, 27 g of xylene was added to the reaction solution and filtered to obtain the following formula (5):
(CH ₃ ) _1.2 (OX) _0.12 SiO _1.34 (5)
(In the formula, X is a combination of hydrogen atom: methyl group: isobutyl group = 3.0: 0.5: 0.6 (molar ratio), and the hydrolysis rate is 95.7 mol%.)
As a result, 135 g of an organopolysiloxane B solution having a weight average molecular weight of 34,000 in terms of polystyrene (including an organic solvent and having a non-volatile content of 57% by mass) is obtained.

Further, 135 g of the obtained organopolysiloxane B solution (containing an organic solvent and having a nonvolatile content of 57% by mass), 36 g of triethylamine and 120 g of xylene were placed in a flask, and then trimethylsilyl at 25 to 60 ° C. with stirring. 26 g of chloride was added dropwise. After completion of dropping, the obtained mixture was reacted at room temperature for 2 hours, and 200 g of water was added dropwise. Thereafter, the reaction solution was put into a separating funnel and separated, and then washed with 200 g of water, and washing was continued until the washing water conductivity after washing was 2.0 μS / cm or less. Then, water is distilled off from the washed reaction solution by azeotropic dehydration, followed by filtration and solvent stripping to obtain the following formula (6):
(CH ₃ ) _1.2 (OX) _0.10 SiO _1.35 (6)
(In the formula, X is a combination of a group represented by —Si (CH ₃ ) ₃ : methyl group: isobutyl group = 2.7: 0.4: 0.5 (molar ratio), and the hydrolysis rate is 96.4 mol%. )
As a result, 71 g of a silylated organopolysiloxane C solution having a polystyrene-reduced weight average molecular weight of 38000 (including an organic solvent and having a nonvolatile content of 92% by mass) was obtained. As reference data, GPC data when MW = 38000 is shown in FIG.

<Synthesis Example 2>
A stirrer and a condenser tube were set in a 1 L three-necked flask. Into this flask, 68.1 g (0.5 mol) of methyltrimethoxysilane, 60.1 g (0.5 mol) of dimethyldimethoxysilane and 118 g of isobutyl alcohol were placed and cooled with ice while stirring. While maintaining the temperature in the system at 0 ° C. to 20 ° C., 54 g of 0.05N hydrochloric acid solution was added dropwise. After completion of the dropwise addition, the obtained mixture was stirred at a reflux temperature of 80 ° C. for 11 hours. Next, the obtained reaction solution was cooled to room temperature, and then diluted with 150 g of xylene. Thereafter, the diluted reaction solution was put into a separating funnel and washed with 300 g of water, and washing was continued until the washing water conductivity after washing was 2.0 μS / cm or less. Then, water is distilled off by azeotropic dehydration of the washed reaction solution, the volatile content is adjusted to 30% by mass, and the following formula (7):
(CH ₃ ) _1.5 (OX) _0.28 SiO _1.11 (7)
(In the formula, X is a combination of hydrogen atom: methyl group: isobutyl group = 7.1: 2.0: 2.1 (molar ratio), and the hydrolysis rate is 88.8 mol%.)
As a result, 109 g of an organopolysiloxane D solution having a weight average molecular weight of 9000 in terms of polystyrene (including an organic solvent and having a nonvolatile content of 70% by mass) was obtained.

Next, 109 g of the obtained organopolysiloxane D solution (containing an organic solvent and having a nonvolatile content of 70% by mass) and a polystyrene-based anion exchange resin (trade name: Diaion SA10A, manufactured by Mitsubishi Chemical Corporation, moisture content) (Content: 43 to 47% by mass) 15.2 g was put in a flask and stirred and mixed at 36 ° C. for 32 hours to be reacted. After completion of the reaction for 32 hours, 25 g of xylene was added to the reaction solution, followed by filtration to obtain the following formula (8):
(CH ₃ ) _1.5 (OX) _0.21 SiO _1.15 (8)
(In the formula, X is a combination of hydrogen atom: methyl group: isobutyl group = 6.1: 1.1: 1.2 (molar ratio), and the hydrolysis rate is 91.6 mol%.)
133 g of an organopolysiloxane E solution having a polystyrene-reduced weight average molecular weight of 30000 (including an organic solvent and a non-volatile content of 57% by mass) was obtained.

Further, 133 g of the obtained organopolysiloxane E solution (containing an organic solvent and having a nonvolatile content of 57% by mass), 36 g of triethylamine and 120 g of xylene were placed in a flask, and then trimethylsilyl at 25 to 60 ° C. with stirring. 26 g of chloride was added dropwise. After completion of dropping, the obtained mixture was reacted at room temperature for 2 hours, and 200 g of water was added dropwise. Thereafter, the reaction solution was put into a separating funnel and separated, and then washed with 200 g of water, and washing was continued until the washing water conductivity after washing was 2.0 μS / cm or less. Then, water is distilled off from the washed reaction solution by azeotropic dehydration, followed by filtration and solvent stripping to obtain the following formula (9):
(CH ₃ ) _1.5 (OX) _0.19 SiO _1.16 (9)
(In the formula, X is a combination of a group represented by —Si (CH ₃ ) ₃ : methyl group: isobutyl group = 5.4: 1.1: 1.1 (molar ratio), and the hydrolysis rate is 92.4 mol%. )
As a result, 70 g of a silylated organopolysiloxane F solution having a polystyrene-reduced weight average molecular weight of 31000 (including an organic solvent and having a nonvolatile content of 91% by mass) was obtained.

<Synthesis Example 3>
A stirrer and a condenser tube were set in a 1 L three-necked flask. Into this flask, 136.2 g (1.0 mol) of methyltrimethoxysilane and 106 g of isobutyl alcohol were placed and cooled with ice while stirring. While maintaining the temperature in the system at 0 ° C. to 20 ° C., 81 g of 0.05N hydrochloric acid solution was added dropwise. After completion of the dropwise addition, the obtained mixture was stirred at a reflux temperature of 80 ° C. for 11 hours. Next, the obtained reaction solution was cooled to room temperature, and then diluted with 150 g of xylene. Thereafter, the diluted reaction solution was put into a separating funnel and washed with 300 g of water, and washing was continued until the washing water conductivity after washing was 2.0 μS / cm or less. Then, water is distilled off by azeotropic dehydration of the washed reaction solution, the volatile content is adjusted to 30% by mass, and the following formula (10):
(CH ₃ ) _1.0 (OX) _0.24 SiO _1.38 (10)
(In the formula, X is a combination of hydrogen atom: methyl group: isobutyl group = 5.5: 1.3: 1.2 (molar ratio), and the hydrolysis rate is 92.0 mol%.)
105 g of an organopolysiloxane G solution having a weight average molecular weight in terms of polystyrene of 21000 represented by (including an organic solvent and having a nonvolatile content of 70% by mass) was obtained.

Next, 105 g of the obtained organopolysiloxane G solution (containing an organic solvent and having a nonvolatile content of 70% by mass) and a polystyrene-based anion exchange resin (trade name: Diaion SA10A, manufactured by Mitsubishi Chemical Corporation, moisture content) (Content: 43 to 47% by mass) 14.7 g was put in a flask and stirred and mixed at 36 ° C. for 32 hours to be reacted. After completion of the reaction for 32 hours, 24 g of xylene was added to the reaction solution, followed by filtration to obtain the following formula (11):
(CH ₃ ) _1.0 (OX) _0.12 SiO _1.44 (11)
(In the formula, X is a combination of hydrogen atom: methyl group: isobutyl group = 3.1: 0.4: 0.5 (molar ratio), and the hydrolysis rate is 96.0 mol%.)
As a result, 124 g of an organopolysiloxane H solution having a polystyrene-equivalent weight average molecular weight of 40000 (including an organic solvent and having a nonvolatile content of 57% by mass) was obtained.

Further, 124 g of the obtained organopolysiloxane H solution (containing an organic solvent and having a nonvolatile content of 57% by mass), 33 g of triethylamine and 120 g of xylene were placed in a flask, and then trimethylsilyl at 25 to 60 ° C. with stirring. 24 g of chloride was added dropwise. After completion of dropping, the obtained mixture was reacted at room temperature for 2 hours, and 200 g of water was added dropwise. Thereafter, the reaction solution was put into a separating funnel and separated, and then washed with 200 g of water, and washing was continued until the washing water conductivity after washing was 2.0 μS / cm or less. Then, water is distilled off from the washed reaction solution by azeotropic dehydration, followed by filtration and solvent stripping to obtain the following formula (12):
(CH ₃ ) _1.0 (OX) _0.10 SiO _1.45 (12)
(In the formula, X is a combination of a group represented by —Si (CH ₃ ) ₃ : methyl group: isobutyl group = 2.6: 0.3: 0.4 (molar ratio), and the hydrolysis rate is 96.7 mol%. )
69 g of a silylated organopolysiloxane I solution having a polystyrene-reduced weight average molecular weight of 41000 (including an organic solvent and having a nonvolatile content of 92% by mass) is obtained.

<Comparative Synthesis Example 1>
A stirrer and a condenser tube were set in a 1 L three-necked flask. Into this flask, 40.9 g (0.3 mol) of methyltrimethoxysilane, 84.1 g (0.7 mol) of dimethyldimethoxysilane and 113 g of isobutyl alcohol were placed and cooled with ice while stirring. While maintaining the temperature in the system at 0 ° C. to 20 ° C., 52 g of 0.05N hydrochloric acid solution was added dropwise. After completion of the dropwise addition, the obtained mixture was stirred at a reflux temperature of 80 ° C. for 11 hours. Next, the obtained reaction solution was cooled to room temperature, and then diluted with 150 g of xylene. Thereafter, the diluted reaction solution was put into a separating funnel and washed with 300 g of water, and washing was continued until the washing water conductivity after washing was 2.0 μS / cm or less. Then, water is distilled off by azeotropic dehydration of the washed reaction solution, the volatile content is adjusted to 30% by mass, and the following formula (13):
(CH ₃ ) _1.7 (OX) _0.25 SiO _1.03 (13)
(In the formula, X is a combination of hydrogen atom: methyl group: isobutyl group = 9.2: 2.7: 2.8 (molar ratio), and the hydrolysis rate is 85.3 mol%.)
As a result, 108 g of an organopolysiloxane J solution having a polystyrene-reduced weight average molecular weight of 7100 (including an organic solvent and having a nonvolatile content of 70% by mass) was obtained.

Next, 108 g of the obtained organopolysiloxane J solution (containing an organic solvent and having a nonvolatile content of 70% by mass) and a polystyrene-based anion exchange resin (trade name: Diaion SA10A, manufactured by Mitsubishi Chemical Corporation, moisture content) (Content: 43 to 47% by mass) 15.1 g was put in a flask and stirred and mixed at 36 ° C. for 32 hours to be reacted. After completion of the reaction for 32 hours, 25 g of xylene was added to the reaction solution, followed by filtration to obtain the following formula (14):
(CH ₃ ) _1.7 (OX) _0.22 SiO _1.04 (14)
(In the formula, X is a combination of hydrogen atom: methyl group: isobutyl group = 8.5: 2.2: 2.2 (molar ratio), and the hydrolysis rate is 87.1 mol%.)
As a result, 129 g of an organopolysiloxane K solution having a weight average molecular weight in terms of polystyrene of 8600 (including an organic solvent and having a nonvolatile content of 57% by mass) was obtained.

Further, 129 g of the obtained organopolysiloxane K solution (containing an organic solvent and having a nonvolatile content of 57% by mass), 33 g of triethylamine and 120 g of xylene were placed in a flask, and then trimethylsilyl chloride was stirred at 25 to 60 ° C. 24 g was added dropwise. After completion of dropping, the obtained mixture was reacted at room temperature for 2 hours, and 200 g of water was added dropwise. Thereafter, the reaction solution was put into a separating funnel and separated, and then washed with 200 g of water, and washing was continued until the washing water conductivity after washing was 2.0 μS / cm or less. Then, water is distilled off from the washed reaction solution by azeotropic dehydration, and filtration and solvent stripping are performed to obtain the following formula (15):
(CH ₃ ) _1.7 (OX) _0.21 SiO _1.05 (15)
(In the formula, X is a combination of a group represented by —Si (CH ₃ ) ₃ : methyl group: isobutyl group = 8.2: 2.1: 2.1 (molar ratio), and the hydrolysis rate is 87.6 mol%. )
As a result, 70 g of a silylated organopolysiloxane L solution having a weight average molecular weight in terms of polystyrene of 8700 (including an organic solvent and having a non-volatile content of 92% by mass) was obtained.

<Comparative Synthesis Example 2>
A stirrer and a condenser tube were set in a 1 L three-necked flask. Into this flask, 40.9 g (0.3 mol) of methyltrimethoxysilane, 170.8 g (0.7 mol) of diphenyldimethoxysilane and 106 g of isobutyl alcohol were placed and cooled with ice while stirring. While maintaining the temperature in the system at 0 to 20 ° C., 55.1 g of 0.05N hydrochloric acid solution was added dropwise. After completion of the dropwise addition, the obtained mixture was stirred at a reflux temperature of 80 ° C. for 11 hours. Next, 150 g of xylene was added to the resulting reaction solution for dilution. Thereafter, the diluted reaction solution was put into a separatory funnel and washed with 300 g of water, and washing was continued until the electric conductivity of the washed water after washing became 2.0 μS / cm or less. Then, water is distilled off by azeotropic dehydration of the washed reaction solution, the volatile content is adjusted to 30% by mass, and the following formula (16):
(CH ₃ ) _0.3 (C ₆ H ₅ ) _1.4 (OX) _0.26 SiO _1.02 (16)
(In the formula, X is a combination of hydrogen atom: methyl group: isobutyl group = 10.1: 2.5: 2.7 (molar ratio), and the hydrolysis rate is 84.7 mol%.)
As a result, 124 g of an organopolysiloxane M solution having a polystyrene-equivalent weight average molecular weight of 6700 (including an organic solvent and having a nonvolatile content of 70% by mass) was obtained.

Next, 124 g of the obtained organopolysiloxane M solution (containing an organic solvent and having a nonvolatile content of 70% by mass) and a polystyrene-based anion exchange resin (trade name: Diaion SA10A, manufactured by Mitsubishi Chemical Corporation, moisture content) (Content: 43-47% by mass) 17.4 g was put in a flask and stirred and mixed at 36 ° C. for 32 hours to be reacted. After completion of the reaction for 32 hours, 25 g of xylene was added to the reaction solution and filtered to obtain the following formula (17):
(CH ₃ ) _0.3 (C ₆ H ₅ ) _1.4 (OX) _0.21 SiO _1.05 (17)
(In the formula, X is a combination of hydrogen atom: methyl group: isobutyl group = 9.5: 1.4: 1.5 (molar ratio), and the hydrolysis rate is 87.6 mol%.)
As a result, 142 g of an organopolysiloxane N solution having a weight average molecular weight in terms of polystyrene of 8400 (including an organic solvent and having a nonvolatile content of 57% by mass) was obtained.

Further, 142 g of the obtained organopolysiloxane N solution (containing an organic solvent and having a nonvolatile content of 57% by mass), 39 g of triethylamine and 120 g of xylene were placed in a flask, and then trimethylsilyl chloride was stirred at 25 to 60 ° C. with stirring. 28 g was added dropwise. After completion of dropping, the obtained mixture was reacted at room temperature for 2 hours, and 200 g of water was added dropwise. Thereafter, the reaction solution was put into a separating funnel and separated, and then washed with 200 g of water, and washing was continued until the washing water conductivity after washing was 2.0 μS / cm or less. Then, water is distilled off from the washed reaction solution by azeotropic dehydration, and filtration and solvent stripping are performed to obtain the following formula (18):
(CH ₃ ) _0.3 (C ₆ H ₅ ) _1.4 (OX) _0.20 SiO _1.05 (18)
(In the formula, X is a combination of a group represented by —Si (CH ₃ ) ₃ : methyl group: isobutyl group = 8.9: 1.4: 1.5 (molar ratio), and the hydrolysis rate is 88.2 mol%. )
78 g of a silylated organopolysiloxane O solution having a weight average molecular weight in terms of polystyrene of 8500 represented by the formula (including an organic solvent and having a nonvolatile content of 92% by mass) was obtained.

<Examples 1-3, Comparative Examples 1-5>
Organopolysiloxanes and silylated organopolysiloxanes obtained in Synthesis Examples 1 to 3 and Comparative Synthesis Examples 1 and 2, aluminum monoacetylacetonate bis (ethylacetoacetate) as a condensation catalyst, and solvents shown in Table 1 It mixed with the compounding quantity (unit: mass part). The composition thus prepared is cured according to the following evaluation method, and the resulting cured product (film) is measured and evaluated for crack resistance, adhesiveness, heat resistance, storage stability and appearance, and further UV irradiation test Went. The obtained results are shown in Table 1.

-Evaluation method-
1. Crack resistance The composition was placed in a 50 mm long x 50 mm wide x 2 mm deep Teflon (registered trademark) coated mold for 0.5 hours at 80 ° C, 1 hour at 150 ° C, and 4 hours at 180 ° C. By performing step cure in order, a cured film having a thickness of 1 mm was produced. The presence or absence of cracks in the cured film was visually observed. A case where no cracks are observed in the cured film is evaluated as “good” and indicated as A, and a case where cracks are observed is evaluated as “bad” and indicated as B. Moreover, the case where the said cured film was not able to be produced is evaluated as "impossible to measure" and is shown as C.

2. Adhesiveness The composition is applied to a glass substrate by a dipping method, followed by step curing in the order of 0.5 hours at 80 ° C., 1 hour at 150 ° C. and 4 hours at 180 ° C. A cured product having a thickness of 2 to 3 μm was formed. The adhesion of the cured product to the glass substrate was examined by a gobang test. Moreover, when the crack generate | occur | produced in this hardened | cured material and adhesiveness was not able to be measured, it shows as x in a table | surface.

3. Heat resistance The composition was placed in a 50 mm long x 50 mm wide x 2 mm deep Teflon (registered trademark) coated mold in the order of 0.5 hours at 80 ° C, 1 hour at 150 ° C, and 4 hours at 180 ° C. A cured film having a thickness of 1 mm was prepared by performing step cure at, and its mass was measured. Next, this cured film was placed in an oven at 250 ° C., and the mass after 500 hours was measured. The ratio of the mass of the cured film after the lapse of 500 hours to the mass of the cured film immediately after production was determined, and was defined as the residual mass ratio (%). The closer this value is to 100%, the better the heat resistance. Moreover, when the said cured film was not able to be produced, it shows as x in a table | surface.

4). Appearance of cured product The composition was placed in a Teflon (registered trademark) coated mold 50 mm long x 50 mm wide x 300 μm deep, 0.5 hours at 80 ° C, 1 hour at 150 ° C, 4 hours at 180 ° C A cured film having a thickness of 200 μm was prepared by performing step cure in the order of. The surface of the cured film was visually observed. In addition, when the crack was recognized, the surface of the part without a crack was observed visually.

5. UV irradiation test 0.1 g of the composition is dropped onto a glass substrate with a dropper and cured on the glass substrate by performing step cure in the order of 0.5 hours at 80 ° C, 1 hour at 150 ° C, and 4 hours at 180 ° C. Formed. The cured product was subjected to UV irradiation (30 mW) for 24 hours using a UV irradiation device (trade name: eye ultraviolet curing device, manufactured by Eye Graphics Co., Ltd.). The surface of the cured product after UV irradiation was visually observed. A case where no deterioration is observed on the surface of the cured product is evaluated as “good” and indicated as “A”, a case where slight deterioration is recognized as “somewhat deteriorated” and indicated as “B”, and a case where significant deterioration is observed. It was evaluated as “deteriorated” and indicated as C.

6). Storage stability The composition was stored at 25 ° C., and the state after 12 hours was observed. When the composition does not show any change such as thickening, it is evaluated as “good” and indicated as A, and when a slight viscosity change is observed, it is evaluated as “slightly changed in viscosity” and indicated as B. Was evaluated as “degraded” and indicated as C.

[Notes on Table 1]
-Unit of blending amount of components (A) to (C): part by mass * The blending amount of organopolysiloxane and silylated organopolysiloxane in the table is the amount of non-volatile content not containing an organic solvent (at 120 ° C / 5mmHg Measured after 3 hours stripping).
* 1 Methyl group content: The theoretical value of methyl groups in organopolysiloxanes or silylated organopolysiloxanes (non-volatile) that do not contain organic solvents.
* 2 The presence or absence of phenyl groups in the organopolysiloxane or silylated organopolysiloxane used.

The figure which shows the result obtained by GPC of the silylated organopolysiloxane used as (A) component of the composition of this invention manufactured by the synthesis example 1. FIG.

Claims (15)

(I) The following average composition formula (1):
R ¹ _a (OX) _b SiO _{(4-ab) / 2} (1)
Wherein R ¹ is independently an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms;
X represents a group represented by the formula: —SiR ² R ³ R ⁴ (wherein R ² , R ³ and R ⁴ are each independently an unsubstituted or substituted monovalent hydrocarbon group), and a carbon atom In combination with an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkoxyalkyl group having 2 to 6 carbon atoms or an acyl group having 2 to 6 carbon atoms, or a combination of two or more of these groups Yes;
a is a number from 1.00 to 1.5;
b is a number satisfying 0 <b <1.5;
However, a + b is 1.00 <a + b <2. )
And a silylated organopolysiloxane (b) condensation catalyst having a polystyrene-equivalent weight average molecular weight of 3 × 10 ⁴ to 50 × 10 ⁴ , and
(C) A resin composition for sealing an optical device containing a solvent. The composition according to claim 1, wherein R ² , R ³ and R ⁴ are methyl groups. The composition according to claim 1 or 2, wherein R ¹ is an alkyl group having 1 to 6 carbon atoms. The composition according to claim 3, wherein R ¹ is a methyl group. The composition according to any one of claims 1 to 4, wherein the ratio of R ^{1 in} the silylated organopolysiloxane of the component (a) is 32% by mass or less.   The composition according to any one of claims 1 to 5, wherein the condensation catalyst of the component (b) is an organometallic catalyst.   The composition according to claim 6, wherein the organometallic catalyst contains tin, zinc, aluminum, titanium, or two or more of these atoms.   The composition according to claim 7, wherein the organometallic catalyst is an aluminum chelate compound.   The composition according to claim 8, wherein the aluminum chelate compound is aluminum monoacetylacetonate bis (ethylacetoacetate).   The solvent of the component (c) contains at least one organic solvent having a boiling point of 150 ° C. or more, and the blending amount of the organic solvent is 50 parts by mass or less with respect to 100 parts by mass of the organopolysiloxane of the component (a). A composition according to any one of claims 1 to 9.   The composition according to claim 10, wherein the organic solvent having a boiling point of 150 ° C or higher is bis (2-methoxyethyl) ether. A transparent cured product obtained by curing the composition according to any one of claims 1 to 11.   A transparent film-like cured product having a thickness of 10 μm to 3 mm obtained by curing the composition according to any one of claims 1 to 11 at a temperature of 100 ° C. or higher.   A method for encapsulating a semiconductor device, comprising: applying the composition according to any one of claims 1 to 11 to a semiconductor device; and curing the composition applied to the semiconductor device.   A resin-encapsulated semiconductor device comprising: a semiconductor element; and a cured product of the composition according to claim 1 that seals the semiconductor element.

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