JP2010265410A - Led sealing agent - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealing agent obtained by curing an organopolysiloxane composition, which is excellent in low moisture permeability. <P>SOLUTION: The sealing agent is an LED sealing agent obtained by curing an organopolysiloxane composition and is characterized in that the steam permeability is ≤50 g/m<SP>2</SP>/24 h. The composition preferably contains (A) an organopolysiloxane having at least two alkenyl groups in one molecule, (B) an organohydrogenpolysiloxane having at least two hydrosilyl groups in one molecule, (C) a hydrosilylation catalyst, and (D) silicone-based particles. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an LED sealing agent having excellent low moisture permeability.

  Silicone rubber has been conventionally used as a sealant used to protect light emitting elements such as light emitting diodes (LEDs) from moisture and dust in the atmosphere (for example, Patent Document 1). However, silicone rubber has a high moisture permeability, and the light emitting characteristics of the light emitting device may be deteriorated by long-term use. In contrast, studies have been made to use a silicone resin as a sealant (for example, Patent Document 2). Silicone resin, which has lower moisture permeability than silicone rubber, has inferior adhesion to light-emitting elements and cold thermal shock resistance, and an LED sealant that combines low moisture permeability and high cold thermal shock resistance has been strongly demanded. .

JP 2009-19205 A JP 2004-221308 A

  This invention is made | formed in view of the said present condition, and aims at providing the LED sealing agent excellent in low moisture permeability.

  As a result of intensive studies to solve the above problems, the present inventors have found that an LED encapsulant having excellent low moisture permeability can be obtained from a cured product obtained by curing a specific organopolysiloxane composition. The headline and the present invention were completed. That is, the present invention has the following configuration.

1) an LED sealing agent obtained by curing the organopolysiloxane composition, the moisture permeability of the sealant, LED sealing agent, characterized in that at most 50g / m ² / 24h.

  2) The LED encapsulant according to 1), wherein an aryl group content in the organopolysiloxane composition is 3 mol% or less.

  3) The LED encapsulant according to 1) or 2), wherein the Shore D hardness of the encapsulant is 20 or more.

  4) The organopolysiloxane composition comprises (A) an organopolysiloxane having at least two alkenyl groups in one molecule, (B) an organohydrogenpolysiloxane having at least two hydrosilyl groups in one molecule, (C LED sealing agent in any one of 1) -3) characterized by including a hydrosilylation catalyst and (D) silicone type particle | grains.

5) The component (A) is represented by the general formula (1)
SiO _4/2 (1)
The main structure is a three-dimensional network structure composed of tetrafunctional structural units represented by general formulas (2) and (3).
R ^a1 R ^a2 ₂ SiO _1/2 (2)
R ^a2 ₃ SiO _1/2 (3)
(Wherein R ^a1 is an alkenyl group, and R ^a2 is a substituted or unsubstituted monovalent hydrocarbon group other than an alkenyl group, which may be the same or different.)
At least two alkenyl groups in one molecule having a structure blocked with a monofunctional structural unit represented by the formula (II) and having at least two terminals of the main structure blocked with the general formula (2). The LED encapsulant as described in 4), which is an organopolysiloxane.

6) The component (B) is represented by the general formula (1)
SiO _4/2 (1)
The main structure is a three-dimensional network structure composed of tetrafunctional structural units represented by general formulas (4) and (5).
R ^b1 R ^b2 ₂ SiO _1/2 (4)
R ^b2 ₃ SiO _1/2 (5)
(In the formula, R ^b1 is a hydrogen atom, R ^b2 is a hydrogen atom, or a substituted or unsubstituted monovalent hydrocarbon group other than an alkenyl group, which may be the same or different.)
And having at least 2 hydrosilyl groups in one molecule having a structure blocked with a monofunctional structural unit represented by formula (1) and having at least two terminals of the main structure blocked with the general formula (4) The LED encapsulant according to 4) or 5), wherein the LED encapsulant is an organohydrogenpolysiloxane.

  7) Component (D) is condensed by adding a first shell component (D-2) obtained by adding and condensing alkoxysilane to silicone particles (D-1), and then adding an alkoxysilane condensate. The silicone polymer particles having a silicone particle core-alkoxysilane condensate shell structure comprising the second shell component (D-3) obtained as described above, and the LED according to any one of 4) to 6) Sealant.

8) The second shell layer composed of the alkoxysilane condensate as component (D-3) has the following component (a) as an essential component, and includes the following components (b), (c) and (d) The sealing agent according to 7), which is obtained by condensing at least one kind.
(A) Component: General formula (6)

(Wherein R ¹² represents an alkyl group, and R ¹³ , R ¹⁴ and R ¹⁵ represent the same or different monovalent organic groups) and / or a partial condensation thereof. object.
(B) Component: General formula (7)

(Wherein R ²² and R ²³ represent the same or different monovalent alkyl groups, and R ²⁴ and R ²⁵ represent the same or different monovalent organic groups) and / Or a partial condensate thereof.
(C) Component: General formula (8)

(Wherein R ³² , R ³³ and R ³⁴ represent the same or different monovalent alkyl groups, and R ³⁵ represents a monovalent organic group) and / or The partial condensate.
(D) Component: General formula (9)

(Wherein R ⁴² , R ⁴³ , R ⁴⁴ and R ⁴⁵ represent the same or different monovalent alkyl group) and / or a partial condensate thereof.

9) The first shell layer composed of the alkoxysilane condensate as component (D-2) is formed by condensing at least one of the following component (b), component (c) and component (d) below. LED sealing agent as described in 7) or 8) characterized by the above-mentioned.
(B) Component: General formula (7)

(Wherein R ²² and R ²³ represent the same or different monovalent alkyl groups, and R ²⁴ and R ²⁵ represent the same or different monovalent organic groups) and / Or a partial condensate thereof.
(C) Component: General formula (8)

(Wherein R ³² , R ³³ and R ³⁴ represent the same or different monovalent alkyl groups, and R ³⁵ represents a monovalent organic group) and / or The partial condensate.
(D) Component: General formula (9)

(Wherein R ⁴² , R ⁴³ , R ⁴⁴ and R ⁴⁵ represent the same or different monovalent alkyl group) and / or a partial condensate thereof.

  10) 1 to 40% by weight of the first shell layer made of an alkoxysilane condensate as the component (D-2) is obtained relative to 40 to 98% by weight of the silicone particles as the component (D-1), (D-3) ) A polymer coated with 1 to 30% by weight of a second shell layer comprising an alkoxysilane condensate as a component (however, the components (D-1), (D-2) and (D-3) are combined) The LED encapsulant according to any one of 7) to 9), wherein the LED encapsulant is 100% by weight).

  11) LED which uses the LED sealing agent in any one of 1) -10).

  From the cured product obtained by curing the organopolysiloxane composition of the present invention, an LED sealing agent having a low moisture permeability can be obtained.

  Hereinafter, the present invention will be described in detail.

Moisture permeability of LED sealant with organopolysiloxane composition of the present invention is 50g / m ² / 24h or less, still more 45g / m ² / 24h or less, particularly 30g / m ² / 24h or less, Is preferred.

The moisture permeability in the present invention is, for example, a value that serves as a measure for suppressing the corrosiveness of a silver lead frame or the like in an LED. If the moisture permeability of the sealant is high, specifically, when greater than 50g / m ² / 24h, the water, and further, a gas such as oxygen is also easily transmitted, silver lead frame of the LED is corroded, There is a risk of degrading the light emission characteristics of the LED.

  The moisture permeability in the present invention is calculated according to the following method.

A 5 ± 0.1 cm square polyisobutylene rubber sheet (3 mm thick, 3 cm square inside cut out in a square shape) on top of a 5 ± 0.1 cm square plate glass (0.5 mm thick) A fixed jig is prepared, and 1 ± 0.1 g of calcium chloride (for moisture measurement) manufactured by Wako Pure Chemical Industries, Ltd. is filled in the square shape. Further, a 5 ± 0.1 cm square cured product for evaluation (3 mm thickness) is fixed to the upper part, and this is used as a test specimen. The test specimen is cured for 24 hours in a thermo-hygrostat (Espec SP-2KP) at a temperature of 40 ° C., humidity and 90% RH.
The water vapor transmission rate is calculated according to equation (10).

Moisture permeability (g / m ² / 24h) = [(total weight of test specimen after moisture permeability test (g)) − (total weight of test specimen before moisture permeability test (g))] / 10000/9 cm ² (10)
The hardness of the cured product in the present invention is preferably 20 or more in Shore D hardness, and more preferably 30 or more in Shore D hardness. When the Shore D hardness is less than 20, the bonding wire connecting the semiconductor element and the electrode may be disconnected by an external force when used as an LED sealant.

<Organosiloxane>
The organosiloxane composition in the present invention becomes an LED sealing agent by curing.

  The aryl group content of the organopolysiloxane composition in the present invention is preferably 3 mol% or less, more preferably 1 mol% or less, and particularly preferably 0 mol%. When the content of the aryl group is large, the heat and light resistance may decrease, and coloring or the like may occur.

  In addition, the structure of the organosiloxane composition in the present invention is not particularly limited, but it may be any as long as it has a siloxane bond and an organic group or a hydrogen atom is bonded to a silicon atom. An curable composition comprising an organopolysiloxane having at least two groups, (B) an organohydrogenpolysiloxane having at least two hydrosilyl groups in one molecule, (C) a hydrosilylation catalyst, and (D) silicone-based particles. Can be mentioned.

  Component (A), component (B) and component (D) are blended in an amount of 98 to 1 weight of component (A) with respect to 100 parts by weight of component (A), component (B) and component (D). Part, (B) component 98 to 1 part by weight, and (D) component 50 to 1 part by weight are preferred. (A) Component 94 to 3 parts by weight, (B) Component 94 to 3 parts by weight, and (D) Component 45 to 3 with respect to 100 parts by weight of the total of component (A), component (B), and component (D) More preferably, it is 90 to 5 parts by weight of component (A), 90 to 5 parts by weight of component (B), and 40 to 5 parts by weight of component (D).

  When there are many compounding quantities of (A) component, the hardened | cured material of sufficient hardness may not be obtained, or hardened | cured material may color. If the amount is too small, a cured product having sufficient hardness may not be obtained. When the blending amount of the component (B) is large, a cured product having sufficient hardness may not be obtained, or foaming may occur during the curing and bubbles may remain in the cured product. If the amount is too small, a cured product having sufficient hardness may not be obtained. When there are many compounding quantities of (D) component, it may thicken at the time of mixing | blending or transparency of hardened | cured material may fall. If it is less, the thermal shock resistance may be insufficient.

About the usage-amount of (C) component, it is preferable to use in the range of 10 ^{< -1} > ^-10 <^-10> mol as a platinum atom with respect to 1 mol of alkenyl groups of (A) component, 10 ^<-4 > ^-10 <^-8> mol. It is more preferable to use within a range. If the platinum catalyst is too much, light having a short wavelength is absorbed, and thus the light resistance of the obtained cured product may be lowered. If it is too little, the matrix may not be cured.

  The viscosity of the organopolysiloxane composition may gradually increase from the viscosity immediately after compounding, but this increase is preferably small from the viewpoint of ease of handling and quality stability. The range of increase in the viscosity is preferably within 20%, more preferably within 10% of the value after standing for 24 hours at 25 ° C. compared to the value immediately after blending.

<(A) Organopolysiloxane having at least two alkenyl groups in one molecule>
The component (A) in the present invention forms a silicone matrix by curing with an organohydrogenpolysiloxane having at least two hydrosilyl groups in one molecule, which will be described later as the component (B), by a hydrosilylation reaction. is there. Therefore, any organopolysiloxane containing two or more alkenyl groups in one molecule is not particularly limited, and widely known ones can be used. The structure may be any of linear, branched, cyclic and three-dimensional cross-linked structures.

  Examples of the linear component (A) include polysiloxanes whose ends are blocked with dimethylvinylsilyl groups, copolymers of dimethylsiloxane units, methylvinylsiloxane units, and terminal trimethylsiloxy units.

  Examples of the cyclic (A) component include 1,3,5,7-tetravinyl-1,3,5,7-tetramethylcyclotetrasiloxane, 1-propyl-3,5,7-trivinyl-1 3,5,7-tetramethylcyclotetrasiloxane, 1,5-divinyl-3,7-dihexyl-1,3,5,7-tetramethylcyclotetrasiloxane, and the like.

Further, examples of the component (A) having a three-dimensional crosslinked structure are not particularly limited, but the general formula (1)
SiO _4/2 (1)
The main structure is a three-dimensional network structure composed of tetrafunctional structural units represented by general formulas (2) and (3).
R ^s1 R ^s2 ₂ SiO _1/2 (2)
R ^s2 ₃ SiO _1/2 (3)
(In the formula, R ^s1 is an alkenyl group, and R ^s2 is a substituted or unsubstituted monovalent hydrocarbon group other than an alkenyl group, which may be the same or different.)
And a structure in which at least two ends of the main structure are blocked by the general formula (2) are exemplified.

  The cured product obtained from the organopolysiloxane composition containing the component (A) represented by the general formula (1), the general formula (2), and the general formula (3) has a high cross-linking density, and thus has high hardness. This is preferable because a high-strength cured product can be obtained.

  The alkenyl group is preferably a vinyl group, an allyl group, a butenyl group, or a hexenyl group, and more preferably a vinyl group from the viewpoints of availability, heat resistance, and light resistance.

  Examples of substituted or unsubstituted monovalent hydrocarbon groups other than alkenyl groups include alkyl groups such as methyl, ethyl, propyl, and butyl groups, cycloalkyl groups such as cyclohexyl groups, phenyl groups, and tolyl groups. The same or different aryl groups or the same or different selected from chloromethyl group, trifluoropropyl group, cyanoethyl group, etc. in which part or all of hydrogen atoms bonded to carbon atoms of these groups are substituted with halogen atoms, cyano groups, etc. Of these, preferred are unsubstituted or substituted monovalent hydrocarbon groups having preferably 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms. Among these, a methyl group is more preferable from the viewpoint of heat resistance and light resistance.

  Furthermore, the component (A) is preferably liquid at room temperature because of easy handling, and the viscosity at room temperature is preferably 1000 Pa · s or less, more preferably 100 Pa · s or less. .

<(B) Organohydrogenpolysiloxane having at least two hydrosilyl groups in one molecule>
In the present invention, the component (B) is cured by a hydrosilylation reaction with the component (A) to form a silicone matrix. For this reason, there is no particular limitation as long as it is an organohydrogenpolysiloxane containing two or more hydrosilyl groups in one molecule, and widely known ones can be used. The structure may be any of linear, branched, cyclic and three-dimensional cross-linked structures.

  Examples of the linear component (B) include polysiloxanes whose ends are blocked with dimethylhydrogensilyl groups, and copolymers of dimethylsiloxane units with methylhydrogensiloxane units and terminal trimethylsiloxy units. sell.

  Examples of the cyclic component (B) include 1,3,5,7-tetrahydrogen-1,3,5,7-tetramethylcyclotetrasiloxane, 1-propyl-3,5,7-trihydro Examples include Gen-1,3,5,7-tetramethylcyclotetrasiloxane, 1,5-dihydrogen-3,7-dihexyl-1,3,5,7-tetramethylcyclotetrasiloxane.

Further, examples of the component (B) having a three-dimensional crosslinked structure are not particularly limited, but the general formula (1)
SiO _4/2 (1)
The main structure is a three-dimensional network structure composed of tetrafunctional structural units represented by general formulas (4) and (5).
R ^b1 R ^b2 ₂ SiO _1/2 (4)
R ^b2 ₃ SiO _1/2 (5)
(In the formula, R ^b1 is a hydrogen atom, R ^b2 is a hydrogen atom, or a substituted or unsubstituted monovalent hydrocarbon group other than an alkenyl group, which may be the same or different.)
Preferred examples include those having a structure blocked with a monofunctional structural unit represented by the formula (II) and having a structure in which at least two terminals of the main structure are blocked with the general formula (4).

  The cured product obtained from the organopolysiloxane composition blended with the component (B) represented by the general formula (1), the general formula (4) and the general formula (5) has a high crosslink density, and thus has high hardness. This is preferable because a high-strength cured product can be obtained.

  Examples of substituted or unsubstituted monovalent hydrocarbon groups other than alkenyl groups include alkyl groups such as methyl, ethyl, propyl, and butyl groups, cycloalkyl groups such as cyclohexyl groups, phenyl groups, and tolyl groups. The same or different aryl groups or the same or different selected from chloromethyl group, trifluoropropyl group, cyanoethyl group, etc. in which part or all of hydrogen atoms bonded to carbon atoms of these groups are substituted with halogen atoms, cyano groups, etc. Of these, preferred are unsubstituted or substituted monovalent hydrocarbon groups having preferably 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms. Among these, a methyl group is more preferable from the viewpoint of heat resistance and light resistance.

  The addition amount of the organohydrogenpolysiloxane is such that the hydrosilyl group of the component (B) is 30 to 500 mol%, preferably 40 to 200 mol% with respect to the alkenyl group of the component (A). Is desirable.

  Furthermore, the component (B) is preferably liquid at room temperature because it is easy to handle. The viscosity at room temperature is preferably 1000 Pa · s or less, and more preferably 100 Pa · s or less. .

<(C) Hydrosilylation catalyst>
As the hydrosilylation catalyst that is the component (C) in the present invention, for example, a platinum-based catalyst, a palladium-based catalyst, and a rhodium-based catalyst can be added. Known platinum-based catalysts can be used. Specifically, platinum element alone, platinum compounds, platinum complexes, chloroplatinic acid, chloroplatinic acid alcohol compounds, aldehyde compounds, ether compounds, various olefins and vinyl Examples include complexes with siloxane. The addition amount of the platinum-based catalyst is preferably in the range of 10 ⁻¹ to 10 ⁻¹⁰ mol as a platinum atom with respect to 1 mol of the alkenyl group of the component (A), and in the range of 10 ⁻⁴ to 10 ⁻⁸ mol. More preferably it is used. If the platinum catalyst is too much, light having a short wavelength is absorbed, and thus the light resistance of the obtained cured product may be lowered. If it is too little, the matrix may not be cured.

<(D) Silicone polymer particles>
The component (D) is a silicone-based particle and preferably has a core-shell structure. The core-shell structure in the present invention can be obtained, for example, by reacting a monomer component having a composition or component different from that of the monomer component forming the core in the presence of the core particle. It is possible to form a core-shell structure while absorbing the shell component into the core particle, or to form an inclined structure from the core part to the shell part, etc., but use a shell component that has reactivity with the core particle. Examples of a preferable structure include particles having a structure in which a shell portion is formed outside the core particle.

  By having a core-shell structure of silicone particles as component (D-1), first shell component as component (D-2), and second shell component as component (D-3), component (D) Can reduce silanol groups on the surface. Thereby, for example, the affinity and compatibility with the matrix can be improved, and the viscosity of the blend when blended in the matrix can be prevented from becoming too high. Furthermore, it is possible to prevent the change of the blend over time, particularly the increase in viscosity.

  Moreover, the hardened | cured material obtained from the organopolysiloxane composition which mix | blended (D) component has a low hygroscopic property, and is preferable at the point which improves a thermal shock resistance.

  The first shell layer made of the alkoxysilane condensate as the component (D-2) is 1 to 40% by weight with respect to 40 to 98% by weight of the silicone particles as the component (D-1), and the component (D-3). A polymer coated with 1 to 30% by weight of a second shell layer made of an alkoxysilane condensate (wherein (D-1), (D-2) and (D-3) are combined to add 100% by weight) %).

  Furthermore, with respect to the silicone particles 35 to 96% by weight as the component (D-1), the first shell layer made of the alkoxysilane condensate as the component (D-2) is 2 to 37% by weight, (D-3 It is more preferable that the second shell layer made of the alkoxysilane condensate as a component is a polymer coated by 2 to 28% by weight.

  When there are few (D-1) components, the softness | flexibility of particle | grains will be impaired, Therefore The cold-heat shock resistance of the hardened | cured material obtained from the organopolysiloxane composition which mix | blended (D) component may fall. When component (D-2) is small, component (D) cannot maintain its original particle shape and component (D) flows out into the matrix, reducing the strength of the cured product obtained from the organopolysiloxane composition. The physical properties may be reduced.

  Moreover, when there are few (D-3) components, the silanol group of the (D) component surface cannot fully be reduced, for example, compatibility with a matrix becomes inadequate or the viscosity of a compounding composition becomes high. Or the viscosity of the cured product obtained from the organopolysiloxane composition containing the component (D) may increase and the thermal shock resistance may decrease.

The component (D-1) may be silicone particles, but the general formula (11)
R ^a _m SiO _{(4-m) / 2} (11)
(Wherein, R ^a is a substituted or unsubstituted monovalent hydrocarbon group, which may be the same or different, and m represents an integer of 0 to 3). It is preferable to consist of organosiloxane having

  In the component (D-1), the structural unit of m = 2 in the general formula (11) preferably accounts for 70 mol% or more of the component (D-1), more preferably 80 mol% or more. Preferably. When the amount of this component is small, the flexibility of the component (D-1) is impaired, so that the cold-heat shock resistance after curing of the organopolysiloxane composition obtained by blending the component (D) into the matrix may decrease. There is a case.

  The component (D-1) can be obtained by polymerization of organosiloxane, and the organosiloxane may be any of linear, branched and cyclic structures, but from the viewpoint of availability and cost, It is preferable to use an organosiloxane having a cyclic structure.

  Specific examples of the organosiloxane include hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), dodecamethylcyclohexasiloxane (D6), and trimethyltriphenylcyclotrisiloxane. In addition to cyclic compounds such as these, linear or branched organosiloxanes can be mentioned. These organosiloxanes can be used alone or in combination of two or more.

  Examples of the substituted or unsubstituted monovalent hydrocarbon group possessed by the organosiloxane include a methyl group, an ethyl group, a propyl group, a phenyl group, and a substituted hydrocarbon group obtained by substituting them with a cyano group. it can.

  Moreover, it is preferable that the terminal of the molecule | numerator of (D-1) component is a silanol group. By having a silanol group at the end of the molecule, a bond is formed by a condensation reaction with the later-described component (D-2). Therefore, silicone polymer particles having a stable core-shell structure are formed. Obtainable.

  The method for producing the component (D-1) is not particularly limited, but it can be obtained by ordinary emulsion polymerization, dispersion polymerization, solution polymerization, and the like. In view of the convenience of the above, it is preferable to obtain by emulsion polymerization.

  The component (D-1) preferably uses seed polymerization in view of the advantage that particles having a smaller particle diameter can be obtained and the particle diameter in the latex state can be narrowed. The seed polymer used for seed polymerization is not particularly limited, but rubber components such as butyl acrylate rubber, butadiene rubber, butadiene-styrene and butadiene-acrylonitrile rubber, butyl acrylate-styrene copolymer, styrene-acrylonitrile copolymer, etc. A polymer can be used.

  The component (D-1) can be produced, for example, by an ordinary emulsion polymerization method performed under acidic or basic conditions, but the reaction under acidic conditions is more than the reaction under basic conditions. This is advantageous because the condensation reaction of alkoxysilane proceeds rapidly. For example, various raw materials containing the above organosiloxane are made into an emulsion using a homomixer, colloid mill, homogenizer, etc. together with an emulsifier and water, and then the pH of the system is adjusted to 5 or less, preferably 4 or less with an acid component, Polymerize by heating. As the acid component used in this case, it is preferable that the emulsion polymerization can proceed stably and also has an emulsifying ability itself, and examples thereof include alkylbenzenesulfonic acid, alkylsulfuric acid, alkylsulfosuccinic acid and the like. .

  After adding all of the raw materials at once, the pH may be adjusted to an arbitrary value after stirring for a certain period of time, or the remaining raw materials in an emulsion in which a part of the raw materials are charged and the pH is adjusted to an arbitrary value May be added sequentially. In the case of sequential addition, it may be added as it is or mixed with water and an emulsifier to form an emulsified liquid, but since the polymerization rate can be increased, a method of adding in an emulsified state is used. It is preferable. The reaction temperature and time are preferably from 0 to 100 ° C, more preferably from 50 to 95 ° C, because of easy reaction control. The reaction time is preferably 1 to 100 hours, more preferably 3 to 50 hours.

  When polymerization is performed under acidic conditions, the Si—O—Si bond forming the skeleton of the component (D-1) is usually in an equilibrium state between cleavage and bond formation. This equilibrium changes depending on the temperature, and the higher the temperature becomes, the easier it is to produce a high molecular weight (D-1) component. Therefore, in order to obtain a high molecular weight (D-1) component, it is preferable to perform aging by polymerizing by heating and then cooling to a polymerization temperature or lower.

  Specifically, the polymerization is carried out at 50 ° C. or higher, and the heating is stopped when the polymerization conversion rate reaches 75 to 90%, more preferably 82 to 89%, and the temperature is lower than the polymerization temperature, for example, 10 to 50 ° C., preferably Can be cooled to 20 to 45 ° C. and aged for about 5 to 100 hours. In addition, the polymerization conversion rate said here means the conversion rate to the (D-1) component of the organosiloxane of the low volatile content in a raw material.

  The amount of water used for the emulsion polymerization is not particularly limited, and may be any amount necessary to emulsify and disperse various raw materials. For example, a weight of 1 to 20 times the total amount of normal raw materials is used. It ’s fine.

  As the emulsifier used for the emulsion polymerization, any known emulsifier can be used without particular limitation as long as it does not lose the emulsifying ability in the pH range where the reaction is carried out. Examples of such emulsifiers include, for example, alkylbenzene sulfonic acid, sodium alkylbenzene sulfonate, sodium alkyl sulfate, sodium alkyl sulfosuccinate, sodium polyoxyethylene nonylphenyl ether sulfonate, and the like. Moreover, there is no limitation in particular in the usage-amount of this emulsifier, What is necessary is just to adjust suitably according to the particle diameter of the target (D-1) component.

  The amount of the emulsifier used is sufficient to obtain a sufficient emulsifying ability and does not adversely affect the properties of the obtained component (D-1) and the silicone polymer particles which are the component (D) obtained therefrom. Therefore, if it dares to illustrate, it is preferable to use 0.005-20 weight% with respect to latex, and it is preferable to use 0.05-15 weight% especially.

  (D-1) The volume average particle diameter of the latex silicone particles as the component is preferably 0.005 μm to 3.0 μm, more preferably 0.01 μm to 2.0 μm, and particularly preferably 0.05 μm to 0.5 μm. . If the volume average particle size is small, it is difficult to obtain stably, and if it is large, the transparency of the cured product may deteriorate. In addition, the measurement of a volume average particle diameter can be performed using nano track particle size analyzer UPA150 (made by Nikkiso Co., Ltd.), for example.

  In synthesizing the component (D-1) used in the present invention, what is called a crosslinking agent or a graft crossing agent can be used if necessary.

  Examples of the crosslinking agent that can be used for the synthesis of the component (D-1) of the present invention include three functional groups that can participate in a condensation reaction such as trimethoxymethylsilane, phenyltrimethoxysilane, and ethyltriethoxysilane. So-called trifunctional crosslinking agent, tetraethoxysilane, 1,3-bis [2- (dimethoxymethylsilyl) ethyl] benzene, 1,4-bis [2- (dimethoxymethylsilyl) ethyl] benzene, 1,3-bis [ 1- (dimethoxymethylsilyl) ethyl] benzene, 1,4-bis [1- (dimethoxymethylsilyl) ethyl] benzene, 1- [1- (dimethoxymethylsilyl) ethyl] -3- [2- (dimethoxymethylsilyl) ) Ethyl] benzene, 1- [1- (dimethoxymethylsilyl) ethyl] -4- [2-dimethoxymethylsilyl] Le] so-called four-functional crosslinking agent 4 containing a functional group capable of participating in condensation reactions such as benzene, more can be mentioned partial condensate obtained by condensation of alkoxy groups of these crosslinking agents.

  These crosslinking agents can be used alone or in combination of two or more as required. The amount of the crosslinking agent used is preferably 0.1 to 10% by weight of the component (D-1). When the use of the crosslinking agent is large, the flexibility of the component (D-1) is impaired, so that when the component (D) is blended in the matrix, the low temperature thermal shock resistance of the organopolysiloxane composition is lowered. There is a case. Moreover, the elasticity of (D-1) component can be arbitrarily adjusted by changing the crosslinking degree by adjusting the usage-amount of a crosslinking agent.

  Examples of the grafting agent that can be used in the present invention include p-vinylphenylmethyldimethoxysilane, p-vinylphenylethyldimethoxysilane, 2- (p-vinylphenyl) ethylmethyldimethoxysilane, and 3- (p-vinylbenzoate). Iloxy) propylmethyldimethoxysilane, p-vinylphenylmethyldimethoxysilane, vinylmethyldimethoxysilane, tetravinyltetramethylcyclosiloxane, allylmethyldimethoxysilane, mercaptopropylmethyldimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, etc. It is done.

  By using the first shell component (D-2) in the present invention, it is possible to maintain the morphology of the component (D) as particles. For example, it can contribute to the improvement of the thermal shock resistance of a cured product obtained from the organopolysiloxane composition.

The alkoxysilane used for the component (D-2) of the present invention is a bifunctional alkoxysilane compound (b) represented by the following general formula (7), represented by the general formula (8) (c) ) Component trifunctional alkoxysilane compounds, tetrafunctional alkoxysilane compounds represented by general formula (9), and partial condensates thereof (partial condensates obtained by condensing alkoxy groups) can be used. (D-2) component is obtained by hydrolyzing and condensing these. These alkoxysilanes can be used alone or in combination of two or more.
(B) Component: General formula (7)

(Wherein R ²² and R ²³ represent the same or different monovalent alkyl groups, and R ²⁴ and R ²⁵ represent the same or different monovalent organic groups) and / Or a partial condensate thereof.
(C) Component: General formula (8)

(Wherein R ³² , R ³³ and R ³⁴ represent the same or different monovalent alkyl groups, and R ³⁵ represents a monovalent organic group) and / or The partial condensate.
(D) Component: General formula (9)

(Wherein R ⁴² , R ⁴³ , R ⁴⁴ and R ⁴⁵ represent the same or different monovalent alkyl group) and / or a partial condensate thereof.

  Examples of the alkoxy group mentioned in the general formulas (7) to (9) include methoxy, ethoxy, normal propoxy, isopropoxy, normal butoxy, isobutoxy, secondary butoxy, tertiary butoxy, pentyloxy, hexyloxy and the like. These are alkoxy groups having 1 to 6 carbon atoms. Examples of the monovalent organic group other than the alkoxy group include an alkyl group, an alkenyl group, an allyl group, and an aralkyl group.

  As a polymerization method for obtaining the component (D-2) using an alkoxysilane compound, emulsion polymerization can be used. Although general conditions can be applied for the emulsion polymerization, it is particularly preferable to pay attention to the polymerization temperature. It is preferable to apply 20-85 degreeC as the temperature in superposition | polymerization. Moreover, 1 to 50 hours of polymerization time can be applied.

  The component (D-2) can be produced by a usual emulsion polymerization method carried out under acidic or basic conditions, but the reaction under acidic conditions is more effective than the reaction under basic conditions. This is advantageous for the reason that gelation is easily suppressed during the condensation reaction of alkoxysilane.

  With the alkoxysilane condensate (D-3) used in the present invention, a large number of silanol groups present on the surfaces of the components (D-1) and (D-2) can be reduced. As a result, various problems derived from the silanol groups on the particle surface, such as problems that the compatibility and affinity between the component (D) and the matrix decrease, and the viscosity of the compound when blended with silicone rubber or silicone resin The problem that it becomes too high and the problem that the composition gradually changes with time can be solved.

  In addition, when such particles containing a large number of silanol groups are blended, for example, the cured product may absorb moisture, and cracks may occur during a cold test. However, such a point can also be solved.

As the component (D-3) of the present invention, a condensate of alkoxysilane is used. As the alkoxysilane, a monofunctional alkoxysilane compound (a) component represented by the following general formula (6) and a partial condensate thereof (partial condensate obtained by condensing an alkoxy group) are essential components. It is preferable. These can be used alone or in combination of two or more.
(A) Component: General formula (6)

(In General Formula (6), R ¹² represents an alkyl group, and R ¹³ , R ¹⁴ , and R ¹⁵ represent the same or different monovalent organic groups.)

  Furthermore, the component (D-3) is preferably formed by condensing at least one of the component (b), the component (c) and the component (d). By combining the component (a) with at least one of the component (b), the component (c), and the component (d), the component (a) can be efficiently incorporated into the component (D). Become.

  In addition, when a component containing an alkenyl group is used in any of (a) to (d), the alkenyl group can be introduced into the component (D). The introduction of the alkenyl group into the component (D) is performed when the component (D) is blended with the matrix component composed of the component (A) and the component (B) that are cured by the hydrosilylation reaction. Since a bond is formed between them, the strength of the cured product obtained from the organopolysiloxane composition of the present invention can be improved, which is preferable.

  As a polymerization method for obtaining the component (D-3) using an alkoxysilane compound, emulsion polymerization can be used. Although general conditions can be applied for the emulsion polymerization, it is particularly preferable to pay attention to the polymerization temperature. It is preferable to apply 20-85 degreeC as the temperature in superposition | polymerization. Moreover, 1 to 50 hours of polymerization time can be applied.

  The component (D-3) can be produced by a usual emulsion polymerization method carried out under acidic or basic conditions, but the reaction under acidic conditions is more preferable than the reaction under basic conditions. This is advantageous for the reason that gelation is easily suppressed during the condensation reaction of alkoxysilane.

  The method for separating particles from the latex of silicone polymer particles (D) obtained by emulsion polymerization is not particularly limited. For example, a metal salt such as calcium chloride, magnesium chloride or magnesium sulfate is added to the latex. Examples of the method include adding the latex to coagulate, separate, wash, dehydrate, and dry the latex. A spray drying method can also be used.

  As a method for separating the particles from the latex, it is preferable to use a masterbatch method because the component (D) can be uniformly dispersed in the matrix resin and a transparent cured product can be obtained.

  The master batch method is an organic solvent that is soluble or partially soluble in water in an aqueous latex solution, such as alcohols (methanol, ethanol, 2-propanol, etc.), ketones (methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.), acetate ester After adding particles (ethyl acetate, butyl acetate, methyl acetate), etc., the particles are slowly aggregated, and then the loose aggregates are recovered by a method such as centrifugal sedimentation or filtration. It can be obtained by redispersing in a solvent, mixing with a matrix resin, and distilling off the solvent.

  The obtained component (D) can be surface-treated within the range not impairing the characteristics of the present invention. By performing the surface treatment, the affinity between the component (D) and the matrix component can be improved.

  As the surface treating agent used at this time, for example, a silylating agent can be used. Examples of the silylating agent used here generally include alkylsilanes such as trimethylchlorosilane, dimethyldichlorosilane, and hexamethyl (di) silazane. These silylating agents can be used alone or in combination of two or more.

  In addition, when the surface treatment is performed, a functional group having binding ability with the matrix component, for example, an alkenyl group, an alkynyl group, or the like is introduced into the surface of the component (D), so that a bond is formed between the component (D) and the matrix component. As a result, the strength of the entire organopolysiloxane composition can be improved.

  As the silylating agent for introducing a functional group having a binding ability with the matrix component to the polymer surface, alkenylsilanes such as chlorodimethylvinylsilane, dichloromethylvinylsilane, dichlorodivinylsilane, and trichlorovinylsilane are generally used. . These silylating agents can be used alone or in combination of two or more.

<Composition and LED sealant>
In the LED sealing agent of this invention, in order to ensure adhesiveness with a base material, an adhesion imparting agent can be added.

  As the adhesion-imparting agent in the present invention, a silane coupling agent, a boron-based coupling agent, a titanium-based coupling agent, an aluminum-based coupling agent, or the like can be preferably used.

  Examples of the silane coupling agent include at least one functional group selected from an epoxy group, a methacryl group, an acrylic group, an isocyanate group, an isocyanurate group, a vinyl group, and a carbamate group in the molecule, and a silicon atom-bonded alkoxy group. A silane coupling agent having a group is preferred. About the said functional group, an epoxy group, a methacryl group, and an acryl group are especially preferable in a molecule | numerator from the point of sclerosis | hardenability and adhesiveness especially.

  Specifically, as the organosilicon compound having an epoxy functional group and a silicon atom-bonded alkoxy group, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2- (3,4-epoxy) And cyclohexyl) ethyltrimethoxysilane and 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane.

  Examples of the organosilicon compound having a methacryl group or an acryl group and a silicon atom-bonded alkoxy group include 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-acrylonitrile. Examples include, but are not limited to, loxypropyltriethoxysilane, methacryloxymethyltrimethoxysilane, methacryloxymethyltriethoxysilane, acryloxymethyltrimethoxysilane, and acryloxymethyltriethoxysilane.

  Examples of boron coupling agents include trimethyl borate, triethyl borate, tri-2-ethylhexyl borate, normal trioctadecyl borate, trinormal octyl borate, triphenyl borate, trimethylene borate, tris (trimethylsilyl) borate, triborate triborate. Examples include, but are not limited to, normal butyl, tri-sec-butyl borate, tri-tert-butyl borate, triisopropyl borate, tripropylpropyl borate, triallyl borate, and boron methoxyethoxide.

  Examples of titanium coupling agents include tetra (n-butoxy) titanium, tetra (i-propoxy) titanium, tetra (stearoxy) titanium, di-i-propoxy-bis (acetylacetonate) titanium, i-propoxy ( 2-ethylhexanediolate) titanium, di-i-propoxy-diethylacetoacetate titanium, hydroxy-bis (lactate) titanium, i-propyltriisostearoyl titanate, i-propyl-tris (dioctylpyrophosphate) titanate, tetra- i-propyl) -bis (dioctyl phosphite) titanate, tetraoctyl-bis (ditridecyl phosphite) titanate, bis (dioctyl pyrophosphate) oxyacetate titanate, bis (dioctyl pyrophosphate) ethylene Taneto, i- propyl trioctanoyl titanate, but i- propyl dimethacrylate -i- stearoyl titanate are exemplified, but not limited thereto.

  Examples of the aluminum coupling agent include, but are not limited to, aluminum butoxide, aluminum isopropoxide, aluminum acetylacetonate, aluminum ethylacetoacetonate, and acetoalkoxyaluminum diisopropylate.

  The adhesiveness imparting agent in the present invention may be used alone or in combination of two or more. The addition amount is preferably 0.05 to 30% by weight of the total weight of the component (A) and the component (B). In addition, depending on the type or amount of the adhesion-imparting agent, there are those that inhibit the hydrosilylation reaction of the matrix resin, so the influence on the hydrosilylation reaction must be considered.

  For the purpose of improving the storage stability of the organopolysiloxane composition used in the present invention or adjusting the reactivity of the hydrosilylation reaction during the curing process, a curing retarder can be used. Known curing retarders can be used, and specific examples include compounds containing aliphatic unsaturated bonds, organic phosphorus compounds, organic sulfur compounds, nitrogen-containing compounds, tin compounds, and organic peroxides. . These may be used alone or in combination of two or more.

  Examples of the compound containing an aliphatic unsaturated bond include 2-phenyl-3-butyn-2-ol, 1-ethynyl-1-cyclohexanol, 3,5-dimethyl-1-hexyn-3-ol, 3 -Methyl-1-hexyn-3-ol, 3-ethyl-1-pentyn-3-ol, 2-methyl-3-butyn-2-ol, 3-methyl-1-pentyn-3-ol, en-in Examples thereof include compounds, maleic esters such as maleic anhydride and dimethyl maleate.

  Examples of the organophosphorus compound include triorganophosphine, diorganophosphine, organophosphon, and triorganophosphite. Examples of organic sulfur compounds include organomercaptans, diorganosulfides, hydrogen sulfide, benzothiazole, thiazole, benzothiazole disulfide, and the like.

  Nitrogen-containing compounds include N, N, N ′, N′-tetramethylethylenediamine, N, N-dimethylethylenediamine, N, N-diethylethylenediamine, N, N-dibutylethylenediamine, N, N-dibutyl-1,3 -Propanediamine, N, N-dimethyl-1,3-propanediamine, N, N, N ', N'-tetraethylethylenediamine, N, N-dibutyl-1,4-butanediamine, 2,2'-bipyridine, etc. Is mentioned.

  Examples of tin compounds include stannous halide dihydrate, stannous carboxylate, and the like. Examples of the organic peroxide include di-t-butyl peroxide, dicumyl peroxide, benzoyl peroxide, and t-butyl perbenzoate.

The addition amount of the curing retardant is not particularly limited, but it is preferably used in the range of 10 ⁻¹ to 10 ⁴ mol, preferably in the range of 1 to 10 ³ mol, per 1 mol of the hydrosilylation catalyst. More preferred. Moreover, these hardening retarders may be used independently and may be used in combination of 2 or more types.

  In the organopolysiloxane composition used in the present invention, fillers such as pulverized quartz, calcium carbonate, and carbon may be added as a bulking agent as needed within a range not impeding the effects of the present invention.

  In addition, the organopolysiloxane composition used in the present invention has various additives such as a colorant and a heat resistance improver, a reaction control agent, a mold release agent, or a filler as necessary, as long as the effects of the present invention are not hindered. A dispersant for the agent can be optionally added.

  Examples of the filler dispersant include diphenylsilane diol, various alkoxysilanes, carbon functional silane, silanol group-containing low molecular weight siloxane, and the like.

Further, in order to make the organopolysiloxane composition of the present invention flame retardant and fire resistant, known additives such as titanium dioxide, manganese carbonate, Fe ₂ O ₃ , ferrite, mica, glass fiber, glass flake and the like are used. It may be added. In addition, it is preferable to stop these arbitrary components to the minimum addition amount so that the effect of this invention may not be impaired.

  In the organopolysiloxane composition used in the present invention, the above components are uniformly mixed using a kneader such as a two-roll, Banbury mixer, kneader, or a planetary stirring deaerator, and heat-treated as necessary. It can obtain by giving.

  The organopolysiloxane composition described in the present invention can be used as a molded article. Examples of molding include arbitrary molding methods such as extrusion molding, compression molding, blow molding, calendar molding, vacuum molding, foam molding, injection molding, and cast molding.

  The method for curing the organopolysiloxane composition used in the present invention is not particularly limited, but it can be reacted by simply mixing the components, or can be reacted by heating. From the viewpoint that the reaction is fast and generally a material having high heat resistance is easily obtained, a method of heating and reacting is preferable.

  Although various reaction temperatures can be set, a temperature range of 25 ° C to 300 ° C is preferable, 30 ° C to 280 ° C is more preferable, and 35 ° C to 260 ° C is more preferable. When the reaction temperature is lower than 25 ° C, the reaction time for sufficient reaction tends to be long, and when the reaction temperature is higher than 300 ° C, the product tends to be thermally deteriorated.

  The reaction may be carried out at a constant temperature, but the temperature may be changed in multiple steps or continuously as required. Rather than carrying out the reaction at a constant temperature, the reaction is preferably carried out while raising the temperature in a multistage manner or continuously in that a uniform cured product without distortion can be easily obtained.

  The pressure during the reaction can be variously set as required, and the reaction can be carried out at normal pressure, high pressure or reduced pressure.

  The cured product obtained by curing the organopolysiloxane composition of the present invention can be used as an LED sealing agent.

  The present invention will be described in more detail based on the following examples, but the present invention is not limited only to these examples.

(Created product for thermal shock test)
Enomoto Co., Ltd. LED package (product name: TOP LED 1-IN-1), 0.4mm x 0.4mm x 0.2mm single crystal silicon chip, Henkel Japan Co., Ltd. epoxy adhesive (product name) : LOCTITE 348), and fixed in an oven at 150 ° C. for 30 minutes. The liquid mixture thus obtained was poured, and a sample was prepared by thermosetting in a convection oven at 80 ° C. × 2 hours, 100 ° C. × 1 hour, 150 ° C. × 5 hours.

(Creating cured product for moisture permeability evaluation test)
The mold was filled with a sealant and heat cured in a convection oven at 80 ° C. × 2 hours, 100 ° C. × 1 hour, 150 ° C. × 5 hours to prepare a sample having a thickness of 3 mm. This cured product was cured at room temperature of 25 ° C. and humidity of 55% RH for 24 hours.

(Thermal shock test)
The cured product for evaluation was subjected to 100 cycles of a high temperature holding at 100 ° C. for 5 minutes and a low temperature holding at −40 ° C. for 5 minutes using a thermal shock tester (TSA-71H-W manufactured by Espec), and then the sample was observed. . After the test, when there was no change visually, it was evaluated as “◯”, and when cracks occurred or peeling occurred between the packages, it was evaluated as “X”.

(Moisture permeability test)
The moisture permeability in the present invention is calculated according to the following method.

A jig is prepared by fixing a 5 cm square polyisobutylene rubber sheet (3 mm thick, 3 cm square inside so as to be a square shape) on top of a 5 cm square plate glass (0.5 mm thick), 1 g of calcium chloride (for water measurement) manufactured by Wako Pure Chemical Industries, Ltd. was filled in a square shape. Further, a 5 cm square cured product for evaluation (thickness: 3 mm) was fixed to the upper part to obtain a test specimen. The specimen was cured for 24 hours at a temperature of 40 ° C., humidity and 90% RH in a thermo-hygrostat (PR-2KP manufactured by Espec), and the total weight of the specimen before and after the test was measured.
The water vapor transmission rate was calculated according to equation (10).

Moisture permeability (g / m ² / 24h) = [(total weight of test specimen after moisture permeability test (g)) − (total weight of test specimen before moisture permeability test (g))] / 10000/9 cm ² (10)

(Shore D hardness)
According to the method described in JIS K6253, measurement was performed using a type D hardness meter manufactured by Kobunshi Keiki Co., Ltd. The average value of the measurement values of five measurements was adopted. In principle, the test piece was conditioned at a temperature of 23 ± 2 ° C. and a relative humidity of 50 ± 5% for 24 hours or more before the test.

(Synthesis Example 1)
After mixing 400 parts by weight of pure water and 12 parts by weight of sodium dodecylbenzenesulfonate (solid content) in a five-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet, monomer addition port, and thermometer The temperature was raised to 50 ° C. in a nitrogen atmosphere. Thereafter, 10 parts by weight of butyl acrylate (BA), 3 parts by weight of t-dodecyl mercaptan and 0.01 part by weight of paramentane hydroperoxide (solid content) were added.

  After 30 minutes, 0.18 part of sodium formaldehyde sulfoxylate (SFS), 0.019 part by weight of ethylenediaminetetraacetic acid (EDTA) and 0.019 part by weight of ferrous sulfate were added and stirred for 1 hour. A mixed solution of 90 parts by weight of BA, 27 parts by weight of t-dodecyl mercaptan and 0.18 parts by weight of paramentane hydroperoxide (solid content) was continuously added over 3 hours. Further, post-polymerization was performed for 1 hour to obtain a latex containing a seed polymer (volume average particle size 0.020 μm).

  Next, in a five-necked flask equipped with a stirrer, a reflux condenser, a nitrogen inlet, a monomer addition port, and a thermometer, 2.0 parts by weight (solid content) of the above seed polymer (10 wt% aqueous solution dodecylbenzene) After charging 1.5 parts by weight of sulfonic acid (solid content) and 300 parts by weight of pure water (including the carry-in from the latex containing the seed polymer), the mixture was stirred for 10 minutes and then the system was heated to 80 ° C. under a nitrogen atmosphere. The temperature was raised to. Separately, a mixture of 150 parts by weight of pure water, 0.5 parts by weight of 5% by weight aqueous sodium dodecylbenzenesulfonate (solid content), 97 parts by weight of octamethylcyclotetrasiloxane, and 3 parts by weight of trimethoxymethylsilane was homogenized. After forcedly emulsifying with a mixer at 8000 rpm for 5 minutes, this mixed solution was continuously added over 3.5 hours. Further, after 2.5 hours of post-polymerization, cooled to 25 ° C. and allowed to stand for 20 hours to complete the polymerization, a latex containing silicone particles (volume average particle size 0.110 μm) as component (D-1) Obtained.

(Synthesis Example 2)
In a five-necked flask equipped with a stirrer, reflux condenser, nitrogen blowing port, monomer addition port, thermometer, 90 parts by weight (solid content) of silicone particles (D-1) component obtained in Synthesis Example 1; In addition, 0.45 parts by weight (solid content) of 10% by weight aqueous solution of dodecylbenzenesulfonic acid was charged, and the temperature was raised to 40 ° C. in a nitrogen atmosphere.

Separately, 40 parts by weight of pure water, 0.1 part by weight (solid content) of 15% by weight aqueous solution of sodium dodecylbenzenesulfonate, 7.30 parts by weight of dimethoxydimethylsilane ((CH ₃ ) ₂ SiO _2/2 Equivalent to 4.5 parts by weight in terms of a complete condensate of the structural unit represented by the following formula: ethyl silicate condensate (manufactured by Tama Chemical Industries, trade name: ethyl silicate 40, SiO ₂ content: 39.0 to 42) 0.0 wt%) 11.16 parts by weight (corresponding to 4.5 parts by weight in terms of the complete condensate of the structural unit represented by SiO ₂ ) was forcibly emulsified with a homomixer at 5000 rpm for 5 minutes. Later, it was added dropwise over 20 minutes. (D-2) component was formed by stirring this solution for 5 hours, keeping at 40 degreeC.

Next, in this solution, 27 parts by weight of pure water and 0.03 part by weight (solid content) of sodium dodecylbenzenesulfonate in a 15% by weight aqueous solution and 6.42 parts by weight of methoxytrimethylsilane ((CH ₃ ) ₃ SiO _{1 / 2} equivalent to 5.0 parts by weight in terms of the complete condensate of the structural unit represented by ₂ ), 1.40 parts by weight of ethoxydimethylvinylsilane (Vi (CH ₃ ) ₂ SiO _1/2 Equivalent to 1.0 part by weight in terms of a complete condensate), 0.81 part by weight of dimethoxydimethylsilane (corresponding to a complete condensate of a structural unit represented by (CH ₃ ) ₂ SiO _2/2 ). corresponding to 5 parts by weight), ethyl silicate condensate (Tama chemical Industries, Ltd., trade name ethyl silicate 40, SiO ₂ content: 39.0 to 42.0 wt%) represented by 1.24 parts by weight (SiO ₂ 0 in terms of the complete condensate of the structural unit The mixture was forcibly emulsified with a homomixer at 5000 rpm for 5 minutes and added dropwise over 10 minutes.

  (D-3) component was formed by stirring this solution for 4.5 hours, keeping at 40 degreeC. The system was cooled to 25 ° C. and allowed to stand for 20 hours to complete the polymerization, and a latex containing silicone polymer particles (volume average particle size 0.112 μm) as component (D) was obtained.

Example 1
A mixed solvent comprising ethyl acetate / methanol = 6/4 (vol / vol) with respect to 35 parts by weight of the resin solid content of the latex (resin solid content concentration 16% by weight) containing the component (D) obtained in Synthesis Example 2. After adding 200 parts by weight to agglomerate the particles, they were spun down at 2000 rpm for 5 minutes in a centrifuge. The obtained precipitate was dispersed and washed in 200 parts by weight of a mixed solvent of ethyl acetate / methanol = 3/7 (vol / vol), and then centrifuged with a centrifuge at 2000 rpm for 5 minutes. The obtained precipitate was further dispersed and washed in 200 parts by weight of a mixed solvent of ethyl acetate / methanol = 4/6 (vol / vol), and then centrifuged at 2000 rpm for 5 minutes with a centrifuge. After this washing was performed three times in total, 350 parts by weight of ethyl acetate was added to 35 parts by weight of the obtained precipitate to obtain an ethyl acetate solution of component (D).

  The vinyl group-containing polysiloxane having a three-dimensional structure as component (A) (made by Clariant, trade name MQV) with respect to 30 parts by weight of the resin solid content of the silicone polymer particles as component (D) thus obtained. -7, vinyl group content 3.5 mol / kg) 36.2 parts by weight, component (B) hydrosilyl group-containing polysiloxane having a three-dimensional structure (manufactured by Clariant, trade name MQH-5, hydrosilyl group) The content of 2.3 mol / kg) is 57.9 parts by weight, and the hydrosilyl group-containing polysiloxane having the same three-dimensional structure as component (B) (manufactured by Clariant, trade name MQH-8, hydrosilyl group content 7) .5 mol / kg) was blended in an amount of 5.9 parts by weight, and the mixture was concentrated by a rotary evaporator to distill off ethyl acetate.

  Thereafter, 5.0 parts by weight of 3-glycidoxypropyltrimethoxysilane, 1.0 part by weight of trimethyl borate, 0.0011 part by weight of 1% xylene solution of 1-ethynyl-1-cyclohexanol, N, N, N ′ , N'-tetramethylethylenediamine 1% xylene solution 0.0010 parts by weight and (C) component platinum vinylsiloxane complex xylene solution (containing 3% by weight platinum) 0.0062 parts by weight Stirring and defoaming were carried out with a type stirring deaerator to obtain a liquid mixture.

  The obtained liquid mixture was cured in accordance with the preparation of each test cured product to obtain a cured sealant.

(Example 2)
36.2 parts by weight of (A) component, a vinyl group-containing polysiloxane having a three-dimensional structure (manufactured by Clariant, trade name MQV-7, vinyl group content 3.5 mol / kg), A hydrosilyl group-containing polysiloxane having a certain three-dimensional structure (manufactured by Clariant, trade name MQH-5, hydrosilyl group content 2.3 mol / kg) is 57.9 parts by weight, and the same three-dimensional component (B) 5.9 parts by weight of a structure-containing hydrosilyl group-containing polysiloxane (manufactured by Clariant, trade name MQH-8, hydrosilyl group content 7.5 mol / kg) was blended, and the mixture was concentrated with a rotary evaporator to obtain ethyl acetate. Was distilled off.

  Thereafter, 5.0 parts by weight of 3-glycidoxypropyltrimethoxysilane, 1.0 part by weight of trimethyl borate, 0.0011 part by weight of 1% xylene solution of 1-ethynyl-1-cyclohexanol, N, N, N ′ , N'-tetramethylethylenediamine 1% xylene solution 0.0010 parts by weight and (C) component platinum vinylsiloxane complex xylene solution (containing 3% by weight platinum) 0.0062 parts by weight Stirring and defoaming were carried out with a type stirring deaerator to obtain a liquid mixture.

  The obtained liquid mixture was cured in accordance with the preparation of each test cured product to obtain a cured sealant.

(Comparative Example 1)
A silicone elastomer liquid mixture (JCR6115 (Toray Dow Corning) A and B were added in equal amounts and stirred and defoamed with a planetary stirring and defoaming machine) was cured according to the preparation of each test cured product. Thus, a cured product was obtained.

  Various test results are shown in Table 1.

  As shown in Table 1, in Example 1 and Example 2, the moisture permeability is 50 g / m 2/24 h or less, and it can be seen that there is an effect of reducing the corrosiveness of the silver lead frame and the like in the LED. Also, it can be seen that when the Shore D altitude is 20 or higher and the LED is sealed, the disconnection of the bonding wire connecting the semiconductor element and the electrode can be reduced. Furthermore, it can be seen that Example 1 also has an excellent effect in the results of the thermal shock test, and is excellent in reliability as an LED sealant expressed by the thermal shock test, moisture permeability, and Shore D hardness.

Claims (11)

An LED sealing agent obtained by curing the organopolysiloxane composition, the moisture permeability of the sealant, LED sealing agent, characterized in that at most 50g / m ² / 24h. 2. The LED encapsulant according to claim 1, wherein an aryl group content in the organopolysiloxane composition is 3 mol% or less. The LED sealant according to claim 1 or 2, wherein the sealant has a Shore D hardness of 20 or more. The organopolysiloxane composition comprises (A) an organopolysiloxane having at least two alkenyl groups in one molecule, (B) an organohydrogenpolysiloxane having at least two hydrosilyl groups in one molecule, and (C) hydrosilyl. LED sealing agent as described in any one of Claims 1-3 characterized by including an oxidation catalyst and (D) silicone type particle | grains. The component (A) is represented by the general formula (1)
SiO _4/2 (1)
The main structure is a three-dimensional network structure composed of tetrafunctional structural units represented by general formulas (2) and (3).
R ^a1 R ^a2 ₂ SiO _1/2 (2)
R ^a2 ₃ SiO _1/2 (3)
(Wherein R ^a1 is an alkenyl group, and R ^a2 is a substituted or unsubstituted monovalent hydrocarbon group other than an alkenyl group, which may be the same or different.)
At least two alkenyl groups in one molecule having a structure blocked with a monofunctional structural unit represented by the formula (II) and having at least two terminals of the main structure blocked with the general formula (2). The LED encapsulant according to claim 4, which is an organopolysiloxane. The component (B) is represented by the general formula (1)
SiO _4/2 (1)
The main structure is a three-dimensional network structure composed of tetrafunctional structural units represented by general formulas (4) and (5).
R ^b1 R ^b2 ₂ SiO _1/2 (4)
R ^b2 ₃ SiO _1/2 (5)
(In the formula, R ^b1 is a hydrogen atom, R ^b2 is a hydrogen atom, or a substituted or unsubstituted monovalent hydrocarbon group other than an alkenyl group, which may be the same or different.)
And having at least 2 hydrosilyl groups in one molecule having a structure blocked with a monofunctional structural unit represented by formula (1) and having at least two terminals of the main structure blocked with the general formula (4) The LED encapsulant according to claim 4, wherein the LED encapsulant is an organohydrogenpolysiloxane. The component (D) is obtained by adding and condensing the first shell component (D-2) obtained by adding alkoxysilane to the silicone particles (D-1) and condensing, and then adding the alkoxysilane condensate. The LED according to any one of claims 4 to 6, wherein the LED is a silicone polymer particle having a silicone particle core-alkoxysilane condensate shell structure comprising the second shell component (D-3) obtained. Sealant. The second shell layer comprising the alkoxysilane condensate as component (D-3) has the following component (a) as an essential component, and at least one of the following component (b), the following component (c) and the following component (d). The sealant according to claim 7, which is obtained by condensing seeds.
(A) Component: General formula (6)

(Wherein R ¹² represents an alkyl group, and R ¹³ , R ¹⁴ and R ¹⁵ represent the same or different monovalent organic groups) and / or a partial condensation thereof. object.
(B) Component: General formula (7)

(Wherein R ²² and R ²³ represent the same or different monovalent alkyl groups, and R ²⁴ and R ²⁵ represent the same or different monovalent organic groups) and / Or a partial condensate thereof.
(C) Component: General formula (8)

(Wherein R ³² , R ³³ and R ³⁴ represent the same or different monovalent alkyl groups, and R ³⁵ represents a monovalent organic group) and / or The partial condensate.
(D) Component: General formula (9)

(Wherein R ⁴² , R ⁴³ , R ⁴⁴ and R ⁴⁵ represent the same or different monovalent alkyl group) and / or a partial condensate thereof. The first shell layer made of an alkoxysilane condensate as component (D-2) is formed by condensing at least one of the following component (b), the following component (c) and the following component (d). The LED encapsulant according to claim 7 or 8.
(B) Component: General formula (7)

(Wherein R ²² and R ²³ represent the same or different monovalent alkyl groups, and R ²⁴ and R ²⁵ represent the same or different monovalent organic groups) and / Or a partial condensate thereof.
(C) Component: General formula (8)

(Wherein R ³² , R ³³ and R ³⁴ represent the same or different monovalent alkyl groups, and R ³⁵ represents a monovalent organic group) and / or The partial condensate.
(D) Component: General formula (9)

(Wherein R ⁴² , R ⁴³ , R ⁴⁴ and R ⁴⁵ represent the same or different monovalent alkyl group) and / or a partial condensate thereof. The first shell layer made of the alkoxysilane condensate as the component (D-2) is 1 to 40% by weight with respect to 40 to 98% by weight of the silicone particles as the component (D-1), and the component (D-3). A polymer coated with 1 to 30% by weight of a second shell layer comprising an alkoxysilane condensate (wherein (D-1) component, (D-2) component and (D-3) component are 100 in total) LED encapsulant according to any one of claims 7 to 9, characterized in that it is% by weight). LED which uses the LED sealing agent as described in any one of Claims 1-10.