JP2018150493A - Silicone resin composition for die bonding and cured product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a silicone resin composition which provides a cured product that has good workability in a transfer method onto a substrate, has a high adhesion force, and has such thermal conductivity as to effectively radiate heat generated from a chip.SOLUTION: A silicone resin composition for die bonding contains (A) linear organopolysiloxane which has at least two alkenyl groups bonded to silicon atoms in one molecule and has no alkoxy group bonded to the silicon atom, (B) three-dimensional net-like organopolysiloxane represented by average composition formula (1), (C) organohydrogenpolysiloxane represented by average composition formula(2), (D) linear organopolysiloxane which has at least one alkenyl group bonded to the silicon atoms and has an alkoxy group bonded to the silicon atom at both terminals of a molecular chain, (E) a platinum group metal-based catalyst, and (F) a thermally conductive filler having an average particle diameter of 0.1 μm or more and less than 1 μm.SELECTED DRAWING: None

Description

  The present invention relates to a silicone resin composition useful for die bonding of a light emitting diode (hereinafter referred to as “LED”) element or the like.

  Conventionally, epoxy resin has been used as a die bond agent (adhesive) for fixing LED elements (chips). However, a die bond agent that fixes blue or white LED elements can be yellowed over time. As in the case of the epoxy sealing material, the die bonding agent absorbs light, resulting in a decrease in luminance (Patent Document 1).

  Currently, the demand for durability of light emitting devices using LEDs as modules is further increased, and LED sealing materials have been replaced by silicones, but die bonding agents are also required to have durability similar to sealing materials. In addition, as a method for adhering the light emitting element to the substrate, a transfer method is widely used in which a die bond agent is formed into a thin film on the eye plate and transferred to the substrate on which the LED element is installed by stamping. For this reason, the die bond agent is required to have good workability when bonding is performed by a transfer method.

  Moreover, since the luminous efficiency of the LED tends to decrease due to deterioration of the member when the light emitting element becomes high temperature, further improvement in heat dissipation is required for the die bond agent. On the other hand, a silicone composition having a heat conductive filler has been proposed as a heat-dissipating die-bonding silicone (Patent Document 2). According to the prior art, it was possible to obtain a composition having a thermal conductivity of 1 W / m · K or less, but with the recent increase in power, the thermal conductivity of the conventional heat-dissipating die-bonding agent silicone However, the heat dissipation is insufficient, and a die bond agent silicone having higher heat dissipation, specifically, a thermal conductivity of 1 W / m · K or more is required.

JP 2006-342200 A JP2015-93970A

  The present invention has been made in view of the above circumstances, has good workability in a transfer method to a substrate, has high adhesion, and has high thermal conductivity so that heat generated from a chip can be effectively dissipated. It aims at providing the silicone resin composition which gives hardened | cured material.

In order to solve the above problems, in the present invention,
(A) a linear organo having at least two alkenyl groups bonded to a silicon atom in one molecule and having no alkoxy group bonded to a silicon atom and having a viscosity at 25 ° C. of 100 mm ² / s or less Polysiloxane,
(B) Three-dimensional network-like organopolysiloxane represented by the following average composition formula (1), which is waxy or solid at 23 ° C .: for a total of 100 parts by mass of the component (A) and the component (B) 60 to 90 parts by mass,
(R ¹ ₃ SiO _1/2 ) _a (R ² R ¹ ₂ SiO _1/2 ) _b (R ² R ¹ SiO) _c (R ¹ ₂ SiO) _d (R ² SiO _3/2 ) _e (R ¹ SiO _3/2 ) _f (SiO _4/2 ) _g (1)
Wherein R ¹ may be the same or different and is a substituted or unsubstituted monovalent hydrocarbon group having no aliphatic unsaturated bond, R ² is an alkenyl group, a, b, c, d, e, f, and g are respectively a ≧ 0, b ≧ 0, c ≧ 0, d ≧ 0, e ≧ 0, f ≧ 0, g ≧ 0, b + c + e> 0, e + f + g> 0, and a + b + c + d + e + f + g = A number satisfying 1).
(C) Organohydrogenpolysiloxane represented by the following average composition formula (2) and having at least two hydrogen atoms bonded to a silicon atom in one molecule: (A) component, (B) component, and ( D) An amount in which hydrogen atoms bonded to silicon atoms in component (C) are 0.5 to 5.0 times moles of all alkenyl groups bonded to silicon atoms in component,
R ³ _h H _i SiO _{(4-hi) / 2} (2)
Wherein R ³ may be the same or different and is a substituted or unsubstituted monovalent hydrocarbon group having no aliphatic unsaturated bond, and h and i are 0.7 ≦ h ≦ 2.1. , 0.001 ≦ i ≦ 1.0 and 0.8 ≦ h + i ≦ 3.0.)
(D) a linear organopolysiloxane having at least one alkenyl group bonded to a silicon atom in one molecule and having an alkoxy group bonded to a silicon atom at both ends of the molecular chain: the component (A) and the above (B) 3 to 30 parts by mass with respect to 100 parts by mass in total of the components,
(E) Platinum group metal-based catalyst: 1 to 500 ppm in terms of the mass of the catalytic metal element with respect to the total amount of the components (A), (B), (C), and (D), and ( F) Thermally conductive filler having an average particle size of 0.1 μm or more and less than 1 μm: total 30 parts by mass of the component (A), the component (B), the component (C), and the component (D) In contrast, 100 to 300 parts by mass,
A silicone resin composition for die bonding is provided.

  With such a silicone resin composition, the workability in the transfer method to the substrate is good, the adhesive force is high, and a cured product having a high thermal conductivity is provided so that the heat generated from the chip can be effectively dissipated. be able to.

  The component (F) preferably contains one or more selected from zinc oxide and alumina.

  If it is such (F) component, it will become a silicone resin composition which gives the hardened | cured material with more favorable heat dissipation.

（式中、シロキサン繰り返し単位の配列は任意であり、ｍ及びｎはそれぞれ、１≦ｍ≦５０、０≦ｎ≦１００を満たす正数である。） Moreover, it is preferable that the said (D) component is a siloxane compound represented by following formula (3).

(In the formula, the arrangement of siloxane repeating units is arbitrary, and m and n are positive numbers satisfying 1 ≦ m ≦ 50 and 0 ≦ n ≦ 100, respectively.)

  If it is such (D) component, the effect of this invention can be acquired more efficiently.

  Furthermore, this invention provides the hardened | cured material obtained by hardening the said silicone resin composition for die bonding.

  Such a cured product has high adhesive strength and high strength, and can effectively dissipate heat generated from the chip.

  As described above, with the silicone resin composition of the present invention, the workability in the transfer method to the substrate is good, the adhesiveness is high, and the thermal conductivity is such that the heat generated from the chip can be effectively dissipated. A high cured product can be provided. Therefore, this silicone resin composition is particularly useful as a die bond material used for die bonding of LED elements and the like.

  As described above, the development of a silicone resin composition that provides a cured product with good workability in the transfer method to the substrate, high adhesion, and high heat conductivity so that the heat generated from the chip can be effectively dissipated. Was demanded.

  As a result of intensive studies on the above problems, the present inventors have found that the silicone resin composition containing the components (A) to (F) described later has a linear chain having an alkoxy group bonded to a silicon atom at both ends of the molecular chain. It has been found that the inclusion of the organopolysiloxane in the form makes it possible to highly fill the thermally conductive filler, and the above-mentioned problems can be achieved, thereby completing the present invention.

That is, the present invention
(A) a linear organo having at least two alkenyl groups bonded to a silicon atom in one molecule and having no alkoxy group bonded to a silicon atom and having a viscosity at 25 ° C. of 100 mm ² / s or less Polysiloxane,
(B) Three-dimensional network-like organopolysiloxane represented by the following average composition formula (1), which is waxy or solid at 23 ° C .: for a total of 100 parts by mass of the component (A) and the component (B) 60 to 90 parts by mass,
(R ¹ ₃ SiO _1/2 ) _a (R ² R ¹ ₂ SiO _1/2 ) _b (R ² R ¹ SiO) _c (R ¹ ₂ SiO) _d (R ² SiO _3/2 ) _e (R ¹ SiO _3/2 ) _f (SiO _4/2 ) _g (1)
Wherein R ¹ may be the same or different and is a substituted or unsubstituted monovalent hydrocarbon group having no aliphatic unsaturated bond, R ² is an alkenyl group, a, b, c, d, e, f, and g are respectively a ≧ 0, b ≧ 0, c ≧ 0, d ≧ 0, e ≧ 0, f ≧ 0, g ≧ 0, b + c + e> 0, e + f + g> 0, and a + b + c + d + e + f + g = A number satisfying 1).
(C) Organohydrogenpolysiloxane represented by the following average composition formula (2) and having at least two hydrogen atoms bonded to a silicon atom in one molecule: (A) component, (B) component, and ( D) An amount in which hydrogen atoms bonded to silicon atoms in component (C) are 0.5 to 5.0 times moles of all alkenyl groups bonded to silicon atoms in component,
R ³ _h H _i SiO _{(4-hi) / 2} (2)
Wherein R ³ may be the same or different and is a substituted or unsubstituted monovalent hydrocarbon group having no aliphatic unsaturated bond, and h and i are 0.7 ≦ h ≦ 2.1. , 0.001 ≦ i ≦ 1.0 and 0.8 ≦ h + i ≦ 3.0.)
(D) a linear organopolysiloxane having at least one alkenyl group bonded to a silicon atom in one molecule and having an alkoxy group bonded to a silicon atom at both ends of the molecular chain: the component (A) and the above (B) 3 to 30 parts by mass with respect to 100 parts by mass in total of the components,
(E) Platinum group metal-based catalyst: 1 to 500 ppm in terms of the mass of the catalytic metal element with respect to the total amount of the components (A), (B), (C), and (D), and ( F) Thermally conductive filler having an average particle size of 0.1 μm or more and less than 1 μm: total 30 parts by mass of the component (A), the component (B), the component (C), and the component (D) In contrast, 100 to 300 parts by mass,
It is the silicone resin composition for die bonding containing this.

  Hereinafter, the present invention will be described in detail, but the present invention is not limited thereto.

[Silicone resin composition for die bonding]
The die-bonding silicone resin composition of the present invention comprises the following components (A) to (F). Hereinafter, each component will be described in detail.

<(A) component>
The component (A) has at least two alkenyl groups bonded to a silicon atom in one molecule and does not have an alkoxy group bonded to a silicon atom, and has a viscosity at 25 ° C. of 100 mm ² / s or less. It is a chain organopolysiloxane.

The component (A) is a component for causing stress relaxation after curing of the composition. Usually, the main chain is composed of repeating diorganosiloxane units, and both ends of the molecular chain are blocked with triorganosiloxy groups. It is an organopolysiloxane having a chain molecular structure. When the viscosity of the component (A) exceeds 100 mm ² / s, this component functions as a soft segment more than necessary, so that it is difficult to obtain high hardness and high adhesive strength, and the viscosity of the composition is remarkably high. The problem of becoming high arises.

  The alkenyl group bonded to the silicon atom is preferably an alkenyl group having 2 to 10 carbon atoms, particularly 2 to 6 carbon atoms such as a vinyl group, an allyl group, or an ethynyl group, and particularly preferably a vinyl group. The alkenyl group bonded to the silicon atom may be present at either the molecular chain end or the molecular chain side chain or in both of them in the molecule of the linear organopolysiloxane of component (A). However, it is preferable that they exist at both ends of the molecular chain.

  In the linear organopolysiloxane molecule of component (A), the organic group bonded to the silicon atom other than the alkenyl group is not particularly limited as long as it does not have an alkoxy group, but carbon A substituted or unsubstituted monovalent hydrocarbon having 1 to 8 is preferable. Examples of the monovalent hydrocarbon include alkyl groups such as methyl group, ethyl group, propyl group and butyl group, cycloalkyl groups such as cyclohexyl group and cyclopentyl group, aryl groups such as phenyl group, tolyl group and xylyl group, benzyl group And aralkyl groups such as phenylethyl group, halogenated hydrocarbon groups such as chloromethyl group, chloropropyl group and chlorocyclohexyl group. An alkyl group is preferable, and a methyl group is particularly preferable.

(A) As a linear organopolysiloxane of a component, what is represented by the following average compositional formula (4) is preferable.
R ⁴ _j R ⁵ _k SiO _{(4-jk) / 2} (4)
(In the formula, R ⁴ may be the same or different and is a substituted or unsubstituted monovalent hydrocarbon group having no aliphatic unsaturated bond, and R ⁵ is an alkenyl group that may be the same or different. , J is a number from 1.9 to 2.1, k is a number from 0.005 to 1.0, and j + k satisfies 1.95 to 3.0.)

In the average composition formula (4), the substituted or unsubstituted monovalent hydrocarbon group having no aliphatic unsaturated bond represented by R ⁴ is an organic group bonded to a silicon atom other than the alkenyl group. The thing similar to what was illustrated is mentioned.

In the average composition formula (4), examples of the alkenyl group represented by R ⁵ include the same groups as those exemplified as the alkenyl group bonded to the silicon atom.

（式中、シロキサン繰り返し単位の配列は任意である。） Specific examples of the component (A) include linear organopolysiloxanes represented by the following formula.

(In the formula, the arrangement of siloxane repeating units is arbitrary.)

  (A) A component may be used individually by 1 type, or may use 2 or more types together.

<(B) component>
(B) A component is a component required in order to acquire reinforcement, maintaining the transparency of a silicone resin composition. Specifically, the component (B) is a three-dimensional network-like organopolysiloxane that is represented by the following average composition formula (1) and is waxy or solid at 23 ° C. The term “wax” means that it is a gum (raw rubber) having a self-fluidity of 10,000 Pa · s or more, particularly 100,000 Pa · s or more, at 23 ° C.
(R ¹ ₃ SiO _1/2 ) _a (R ² R ¹ ₂ SiO _1/2 ) _b (R ² R ¹ SiO) _c (R ¹ ₂ SiO) _d (R ² SiO _3/2 ) _e (R ¹ SiO _3/2 ) _f (SiO _4/2 ) _g (1)
Wherein R ¹ may be the same or different and is a substituted or unsubstituted monovalent hydrocarbon group having no aliphatic unsaturated bond, R ² is an alkenyl group, a, b, c, d, e, f, and g are respectively a ≧ 0, b ≧ 0, c ≧ 0, d ≧ 0, e ≧ 0, f ≧ 0, g ≧ 0, b + c + e> 0, e + f + g> 0, and a + b + c + d + e + f + g = Number that satisfies 1.)

In the average composition formula (1), the substituted or unsubstituted monovalent hydrocarbon group having no aliphatic unsaturated bond represented by R ¹ is a silicon atom other than an alkenyl group in the component (A). the same as those exemplified as combined organic group, but is preferably 80% or more of the total R ¹ is a methyl group. When the proportion of the methyl groups at least 80 mole% of the total R ^1, compatibility with the component (A) is good, it is that the composition does not turbid, to obtain a cured product with high transparency.

In the average composition formula (1), examples of the alkenyl group represented by R ² include the same alkenyl groups as those exemplified as the alkenyl group bonded to the silicon atom in the component (A). A vinyl group is preferable from the viewpoint of ease and price.

  In the average composition formula (1), a, b, c, d, e, f, and g are a ≧ 0, b ≧ 0, c ≧ 0, d ≧ 0, e ≧ 0, f ≧ 0, It is a number satisfying g ≧ 0, b + c + e> 0, e + f + g> 0, and a + b + c + d + e + f + g = 1, a is 0 to 0.65, b is 0 to 0.65, c is 0 to 0.5, d is 0 to 0 0.5, e0 to 0.8, f is preferably 0 to 0.8, and g is preferably 0 to 0.6. Further, b + c + e is preferably a number of 0.1 to 0.8, particularly 0.2 to 0.65, and e + f + g is a number of 0.1 to 0.8, particularly 0.2 to 0.6. It is preferable.

  In the component (B), the content of the alkenyl group bonded to the silicon atom is preferably in the range of 0.01 to 1 mol per 100 g of the component (B), and in the range of 0.05 to 0.5 mol. Is more preferable. When the content is in the range of 0.01 to 1 mol, the crosslinking reaction proceeds sufficiently, and a cured product having higher hardness is obtained.

The organopolysiloxane (B) has a branched structure. The organopolysiloxane of component (B) is composed of SiO _4/2 units and / or SiO _3/2 units (that is, SiO _4/2 units, R ² SiO _3/2 units _, and / or R ¹ SiO _3/2 units). ), but branched structure comprising as essential from further methylvinyl siloxy units, SiO _2/2 units such as dimethylsiloxy units, dimethylvinylsiloxy units may include SiO _1/2 units, such as trimethylsiloxy units. The content of SiO _4/2 units and / or SiO _3/2 units is preferably 5 mol% or more, more preferably 10 mol to 95 mol% of all siloxane units in the organopolysiloxane resin of component (B), Most preferably, it is 20-60 mol%.

  Further, the organopolysiloxane as the component (B) preferably has a weight average molecular weight in the range of 500 to 100,000 from the viewpoint of easy isolation.

  The ratio of the component (B) to the component (A) is also an important factor of the composition of the present invention. (B) The compounding quantity of a component needs to be 60-90 mass parts with respect to a total of 100 mass parts of (A) component and (B) component, Preferably it is 65-80 mass parts, More preferably, it is 65-65 mass parts. 75 parts by mass. When the blending amount of the component (B) is less than 60 parts by mass, a cured product with poor adhesion or high hardness may not be obtained. When it exceeds 90 parts by mass, the viscosity of the composition is remarkably high. It becomes high, it becomes difficult to transfer, and handling at the time of using a composition for die-bonding materials etc. becomes difficult.

Specific examples of the component (B) include the following.
(CH ₂ = CH (CH ₃ ) ₂ SiO _1/2 ) _0.1 ((CH ₃ ) ₃ SiO _1/2 ) _0.4 (SiO _4/2 ) _0.5 ,
(CH ₂ = CH (CH ₃ ) ₂ SiO _1/2 ) _0.2 ((CH ₃ ) ₂ SiO _2/2 ) _0.25 ((CH ₃ ) SiO _3/2 ) _0.55 ,
(CH ₂ = CH (CH ₃ ) SiO _2/2 ) _0.4 ((CH ₃ ) ₂ SiO _2/2 ) _0.15 ((CH ₃ ) SiO _3/2 ) _0.45

  (B) A component may be used individually by 1 type, or may use 2 or more types together.

<(C) component>
The component (C) is a component that acts as a crosslinking agent that reacts and crosslinks with the alkenyl group contained in the component (A), the component (B), and the component (D) by a hydrosilylation reaction. 2) is an organohydrogenpolysiloxane having at least two hydrogen atoms bonded to silicon atoms in one molecule.
R ³ _h H _i SiO _{(4-hi) / 2} (2)
Wherein R ³ may be the same or different and is a substituted or unsubstituted monovalent hydrocarbon group having no aliphatic unsaturated bond, and h and i are 0.7 ≦ h ≦ 2.1. , 0.001 ≦ i ≦ 1.0 and 0.8 ≦ h + i ≦ 3.0.)

  The compounding amount of the component (C) is such that the hydrogen atoms bonded to the silicon atoms in the component (C) are 0. 0 with respect to all silicon atom-bonded alkenyl groups in the components (A), (B), and (D). The amount is 5 to 5.0 times mol, preferably 0.7 to 3.0 times mol. If it falls below this range, crosslinking does not proceed sufficiently, and a hardened product may not be obtained. Moreover, when it exceeds this range, a crosslinking density will become low and the intensity | strength of hardened | cured material may fall.

  In the component (C), the content of hydrogen atoms bonded to the silicon atom is preferably in the range of 0.001 to 0.02 mol, and 0.002 to 0.017 mol per gram of the component (C). A range is more preferable.

  The component (C) preferably has a viscosity at 25 ° C. of 100 mPa · s or less, and more preferably in the range of 5 to 100 mPa · s.

In the above average composition formula (2), the substituted or unsubstituted monovalent hydrocarbon group having no aliphatic unsaturated bond represented by R ³ is a silicon atom other than an alkenyl group in the component (A). While those similar to those exemplified as combined organic groups, preferably at least 50 mol% are methyl groups of all R ^3, and more preferably 60 to 100 mol% are methyl groups. If the ratio of a methyl group is in the said range, it is excellent in compatibility with (A) component and (B) component, and can suppress problems, such as cloudiness or a phase separation of a composition.

  In the average composition formula (2), h and i are positive numbers that satisfy 0.7 ≦ h ≦ 2.1, 0.001 ≦ i ≦ 1.0, and 0.8 ≦ h + i ≦ 3.0. 1.0 ≦ h ≦ 2.0, 0.01 ≦ i ≦ 1.0, and 1.5 ≦ h + i ≦ 2.5.

  The component (C) contains at least two hydrogen atoms bonded to silicon atoms in one molecule. The number of hydrogen atoms bonded to silicon atoms in one molecule is preferably 2 to 200, more preferably 3 to 100, and still more preferably 4 to 50.

  In the component (C), the hydrogen atom bonded to the silicon atom may be located at either the molecular chain end or the molecular chain, or may be located at both of them. In addition, the molecular structure of the organohydrogenpolysiloxane of component (C) may be any of linear, cyclic, branched, and three-dimensional network structures, but the number of silicon atoms in one molecule (or polymerization) Degree) is preferably 2 to 300, more preferably 3 to 200.

  Examples of the organohydrogenpolysiloxane represented by the average composition formula (2) include 1,1,3,3-tetramethyldisiloxane, 1,3,5,7-tetramethylcyclotetrasiloxane, tris ( Hydrogendimethylsiloxy) methylsilane, tris (hydrogendimethylsiloxy) phenylsilane, methylhydrogencyclopolysiloxane, methylhydrogensiloxane-dimethylsiloxane cyclic copolymer, both ends trimethylsiloxy group-blocked methylhydrogenpolysiloxane, both ends Trimethylsiloxy group-blocked dimethylsiloxane / methylhydrogensiloxane copolymer, both ends dimethylhydrogensiloxy group-blocked dimethylpolysiloxane, both ends dimethylhydrogensiloxy group-blocked methyl Drogen polysiloxane, both ends dimethylhydrogensiloxy-blocked dimethylsiloxane / methylhydrogensiloxane copolymer, both ends trimethylsiloxy-blocked methylhydrogensiloxane / diphenylsiloxane copolymer, both ends trimethylsiloxy-blocked methylhydrogen Siloxane / diphenylsiloxane / dimethylsiloxane copolymer, both ends trimethylsiloxy group-capped methylhydrogensiloxane / methylphenylsiloxane / dimethylsiloxane copolymer, both ends dimethylhydrogensiloxy group-capped methylhydrogensiloxane / dimethylsiloxane / diphenylsiloxane Copolymer, dimethylhydrogensiloxy group-blocked methylhydrogensiloxane / dimethylsiloxane Methylphenylsiloxane copolymers.

（式中、シロキサン繰り返し単位の配列は任意である。） Specific examples of the component (C) include the following.

(In the formula, the arrangement of siloxane repeating units is arbitrary.)

  (C) A component may be used individually by 1 type, or may use 2 or more types together.

<(D) component>
Component (D) is a linear organopolysiloxane having at least one alkenyl group bonded to a silicon atom in one molecule and having an alkoxy group bonded to a silicon atom at both ends of the molecular chain.

  This component acts as a wetter and is a component necessary for highly filling the component (F) described later by having an alkoxy group. Furthermore, in order to efficiently fill the component (F) with high efficiency, the component (D) preferably has a degree of polymerization of 150 or less. If it is this range, the viscosity raise of a composition can be suppressed.

  Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, and a butoxy group, and a methoxy group is particularly preferable.

  The component (D) has at least one alkenyl group bonded to a silicon atom in one molecule. The number of alkenyl groups bonded to silicon atoms in one molecule is preferably 1 to 50, and more preferably 1 to 20. When the alkenyl group is not included in the molecule, the crosslinking reaction with the component (C) does not proceed, and thus the bleeding of this component from the LED chip (bleed out) occurs after curing. If bleed-out occurs, not only the appearance of the product is impaired, but also the adhesive strength may be lowered, which is not preferable. Moreover, if the number of alkenyl groups in one molecule is 50 or less, there is no possibility that the cured product becomes brittle after the crosslinking reaction or the adhesive strength is not lowered.

  As said alkenyl group, the thing similar to what was illustrated as an alkenyl group couple | bonded with the silicon atom in the above-mentioned (A) component is mentioned.

  (D) The compounding quantity of a component is 3-30 mass parts with respect to a total of 100 mass parts of (A) component and (B) component, Preferably it is 10-25 mass parts, More preferably, it is 12-20 mass parts. . When the blending amount is less than the above range, the component (F) described later cannot be highly filled, workability in the transfer method is deteriorated, and a cured product having high thermal conductivity cannot be obtained. Moreover, when the compounding quantity of (D) component exceeds the said range, the hardness of hardened | cured material may be reduced and die shear strength may be inferior.

（式中、シロキサン繰り返し単位の配列は任意であり、ｍ及びｎはそれぞれ、１≦ｍ≦５０、０≦ｎ≦１００を満たす正数である。） (D) As an example of a component, the siloxane compound represented by following formula (3) is mentioned.

(In the formula, the arrangement of siloxane repeating units is arbitrary, and m and n are positive numbers satisfying 1 ≦ m ≦ 50 and 0 ≦ n ≦ 100, respectively.)

Specific examples of the structure include the following.

  (D) A component may be used individually by 1 type, or may use 2 or more types together.

<(E) component>
The platinum group metal catalyst of component (E) in the present invention comprises an alkenyl group in component (A), component (B), and component (D) and a hydrogen atom bonded to a silicon atom in component (C). It promotes the addition reaction. Specific examples thereof include platinum group metals such as platinum, palladium and rhodium, chloroplatinic acid, alcohol-modified chloroplatinic acid, coordination compounds of chloroplatinic acid and olefins, vinyl siloxane or acetylene compounds, tetrakis (triphenylphosphine). ) Platinum group metal compounds such as palladium and chlorotris (triphenylphosphine) rhodium are exemplified, and platinum compounds are particularly preferred.

  (E) A component may be used individually by 1 type, or may use 2 or more types together.

  (E) The compounding quantity of a component is an effective amount as a catalyst, and is the mass conversion of a catalytic metal element with respect to the total amount of (A) component, (B) component, (C) component, and (D) component. Is in the range of 1 to 500 ppm, preferably in the range of 1 to 100 ppm. If it is in the said range, the reaction rate of addition reaction will become appropriate, and the hardened | cured material which has high intensity | strength can be obtained.

<(F) component>
The component (F) in the present invention is for imparting thermal conductivity (heat dissipation) to the obtained silicone resin composition, and is a thermal conductive filler having an average particle size of 0.1 μm or more and less than 1 μm. is there.

  Examples of the thermally conductive filler include zinc oxide, alumina, boron nitride, and aluminum nitride. Among these, zinc oxide and alumina are preferable from the viewpoints of thermal conductivity, moisture resistance, and average particle size.

  (F) A component may be used individually by 1 type, or may use 2 or more types together.

  In order to efficiently dissipate the heat from the light emitting element, the average particle size of the heat conductive filler needs to be 0.1 μm or more and less than 1 μm, preferably 0.1 to 0.9 μm, 0 3 to 0.9 μm is more preferable. When the average particle diameter is 1 μm or more, the thickness when the silicone resin composition is used as a die bond material is increased, and the heat dissipation of heat generated from the light emitting element to be bonded is deteriorated. On the other hand, when the average particle size is less than 0.1 μm, the viscosity of the composition increases and transferability deteriorates.

  (F) The compounding quantity of a component is 100-300 mass parts with respect to a total of 30 mass parts of (A) component, (B) component, (C) component, and (D) component, Preferably it is 100- 200 parts by mass. When the said compounding quantity is less than 100 mass parts, there exists a possibility that the target heat conductivity (1.0 W / mK or more) may not be obtained. When the blending amount is larger than 300 parts by mass, the resulting silicone resin composition has a too high viscosity, and stringiness appears, making it difficult to apply the composition by a transfer method.

<Other ingredients>
Components such as an adhesion improver and a reaction inhibitor may be added to the silicone resin composition of the present invention depending on the purpose.

  As an adhesion improver, from the viewpoint of imparting self-adhesiveness to the composition of the present invention that is an addition reaction curable type, organosilicon compounds such as silane and siloxane containing a functional group imparting adhesiveness, non-silicone type Organic compounds and the like are preferably used.

  Specific examples of the functional group imparting adhesiveness include vinyl groups bonded to silicon atoms, alkenyl groups such as allyl groups, or hydrogen atoms; epoxy groups bonded to silicon atoms via carbon atoms (for example, γ-glycid Alkoxypropyl group, β- (3,4-epoxycyclohexyl) ethyl group, etc.), acryloxy group (eg, γ-acryloxypropyl group, etc.), or methacryloxy group (eg, γ-methacryloxypropyl group, etc.); alkoxysilyl Groups (for example, alkoxysilyl such as trimethoxysilyl group, triethoxysilyl group, methyldimethoxysilyl group, etc. bonded to a silicon atom via an alkylene group which may contain 1 to 2 ester structures, urethane structures or ether structures) Group).

  Examples of the organosilicon compound containing a functional group that imparts adhesiveness include a silane coupling agent, a siloxane having an alkoxysilyl group and an organic functional group, a compound in which an alkoxysilyl group is introduced into an organic compound having a reactive organic group, etc. Is exemplified.

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

  Reaction inhibitors include phosphorus-containing compounds such as triphenylphosphine; nitrogen-containing compounds such as tributylamine, tetramethylethylenediamine, and benzotriazole; sulfur-containing compounds; acetylene-based compounds; hydroperoxy compounds; maleic acid derivatives; Such as cyclohexanol, 3,5-dimethyl-1-hexyn-3-ol, ethynylmethyldecylcarbinol, 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane, The well-known compound which has a hardening inhibitory effect with respect to the platinum group metal catalyst of the said (E) component is illustrated.

  Since the degree of the curing inhibitory effect of the reaction inhibitor varies depending on the chemical structure of the reaction inhibitor, it is desirable to adjust the blending amount of the reaction inhibitor to an optimum amount for each reaction inhibitor used. Preferably, it is 0.001-5 mass parts with respect to 30 mass parts in total of (A) component, (B) component, (C) component, and (D) component. If the amount is 0.001 part by mass or more, the long-term storage stability of the composition at room temperature can be sufficiently obtained. When the blending amount is 5 parts by mass or less, there is no fear that the curing of the composition is inhibited.

  Other optional components include, for example, crystalline silica, hollow filler, silsesquioxane, and other inorganic fillers, and these fillers include organoalkoxysilane compounds, organochlorosilane compounds, organosilazane compounds, and low molecular weight siloxane compounds. Examples of the filler include a surface hydrophobized treatment with an organosilicon compound such as silicone rubber powder and silicone resin powder.

  In order to improve the workability in the transfer method, the viscosity of the silicone resin composition of the present invention is preferably 5 to 100 Pa · s, more preferably 20 to 50 Pa · s as measured at 25 ° C. with a rotational viscometer. It is.

[Cured product]
Furthermore, this invention provides the hardened | cured material obtained by hardening the said silicone resin composition for die bonding.

  As the curing method and conditions for the silicone resin composition of the present invention, known curing methods and conditions can be employed. As an example, it can be cured at 100 to 180 ° C. for 10 minutes to 5 hours.

  The thermal conductivity of the cured product obtained by curing the silicone resin composition of the present invention is preferably 1.0 W / m · K or more, and the Type D hardness of the cured product is preferably 30 or more. The die shear strength is preferably 15 MPa or more at 25 ° C.

  As described above, with the silicone resin composition of the present invention, the workability in the transfer method to the substrate is good, the adhesive force is high, the heat generated from the chip can be effectively dissipated, and the high-strength curing It becomes the silicone resin composition which gives a thing. Such a silicone resin composition is particularly useful as a die bond material used for die bonding of LED elements and the like.

Hereinafter, the present invention will be specifically described with reference to Synthesis Examples, Examples, and Comparative Examples, but the present invention is not limited thereto. In addition, each symbol used here has shown the following structures, respectively.
D: Si (CH ₃ ) ₂ O
D ^Vi : Si (CH═CH ₂ ) (CH ₃ ) O
M ^OH : SiOH (CH ₃ ) ₂ O _1/2
M ^OMe : Si (OMe) ₃ O _1/2

[Synthesis Example 1]
Stirrer, condenser tube, a dropping funnel, and linear organopolysiloxanes expressed by ^M _OH 2 ^_D 7 _D ^Vi four-necked flask 500mL equipped with a thermometer (OH amount: 0.18mol / 100g) 200g And 89 g of a compound represented by the following structural formula (I) was added dropwise with stirring. Then, it mixed at 85 degreeC for 2 hours, reaction was performed, and it cooled to 25 degreeC. After cooling, 16 g of methanol was added, mixed at 25 ° C. for 2 hours, and then concentrated under reduced pressure at 150 ° C. for 1 hour, whereby a linear organopolysiloxane represented by M ^OMe ₂ D ₉ D ^Vi (D- 1) was obtained.

[Synthesis Example 2]
Stirrer, condenser tube, a dropping funnel, and linear organopolysiloxanes expressed by ^M _OH 2 ^_D 27 _D ^Vi ₉ four-necked flask 500mL equipped with a thermometer (OH amount: 0.07 mol / 100 g) 200 g was added, and 33 g of the compound represented by the structural formula (I) was added dropwise with stirring. Then, it mixed at 85 degreeC for 2 hours, reaction was performed, and it cooled to 25 degreeC. After cooling, 16 g of methanol was added, mixed at 25 ° C. for 2 hours, and then concentrated under reduced pressure at 150 ° C. for 1 hour, whereby a linear organopolysiloxane represented by M ^OMe ₂ D ₂₉ D ^Vi ₉ ( D-2) was obtained.

[Synthesis Example 3]
200 g of a linear organopolysiloxane (OH amount: 0.18 mol / 100 g) represented by ^MOH ₂ D ₈ is placed in a 500 mL four-necked flask equipped with a stirrer, a condenser, a dropping funnel, and a thermometer. While stirring, 89 g of the compound represented by the structural formula (I) was dropped. Then, it mixed at 85 degreeC for 2 hours, reaction was performed, and it cooled to 25 degreeC. After cooling, 16 g of methanol was added, mixed at 25 ° C. for 2 hours, and then concentrated under reduced pressure at 150 ° C. for 1 hour, whereby a linear organopolysiloxane represented by M ^OMe ₂ D ₁₀ (D-3 )

[Examples 1 to 3, Comparative Examples 1 to 4]
The following components were mixed in the blending amounts shown in Table 1 to prepare a silicone resin composition. In addition, the numerical value of each component in Table 1 represents a mass part. The viscosity is a value measured at 25 ° C. using a rotational viscometer, and the [Si-H] / [Si-Vi] values are in the (A) component, (B) component, and (D) component. Represents the molar ratio of hydrogen atoms bonded to silicon atoms in component (C) with respect to all silicon-bonded alkenyl groups.

(A) Component: (CH ₂ ═CH (CH ₃ ) ₂ SiO _1/2 ) ₂ ((CH ₃ ) ₂ SiO) ₁₀ , linear dimethylpolysiloxane having both ends blocked with vinyl groups Siloxane (viscosity at 25 ° C. 8.7 mm ² / s)
(B) Component: (CH ₂ = CH (CH ₃ ) ₂ SiO _1/2 ) _1.2 ((CH ₃ ) ₃ SiO _1/2 ) _7.4 Branched silicone represented by (SiO ₂ ) ₁₀ Resin (solid at 23 ° C., vinyl group content 0.085 mol / 100 g based on solid content)
(C) component: methyl hydrogen polysiloxane (D) component represented by ((CH ₃ ) ₃ SiO _1/2 ) ₂ ((CH ₃ ) ₂ SiO) _14.5 (H (CH ₃ ) SiO) ₃₈ :
(D-1) Linear dimethylpolysiloxane prepared in Synthesis Example 1 (D-2) Linear dimethylpolysiloxane prepared in Synthesis Example 2 (D-3) Linear dimethylpolysiloxane prepared in Synthesis Example 3 Siloxane (E) component: siloxane of a reaction product of hexachloroplatinic acid and 1,3-divinyltetramethyldisiloxane {viscosity 60 mm ² / s, average molecular formula (CH ₂ = CH (CH ₃ ) ₂ SiO _1/2 ) ₂ ((CH ₃ ) ₂ SiO) ₄₀ } solution (platinum content is 0.004% by mass)
Component (F): True spherical alumina having an average particle size of 0.9 μm (AL-47-1, Showa Denko KK)
(G) Component: Control agent (1-ethynylcyclohexanol)
(H) component: Adhesion improver (triallyl isocyanurate)

  The silicone resin compositions obtained in Examples 1 to 3 and Comparative Examples 1 to 4 were evaluated as follows, and the results are shown in Table 2.

[Hardness of cured product]
The composition obtained in each Example and each Comparative Example was heated at 150 ° C. for 2 hours, and the type D hardness of the obtained cured product was measured according to JIS K 6253.

[Thermal conductivity]
The composition obtained in each Example and each Comparative Example was heated at 150 ° C. for 2 hours, and the obtained cured product was subjected to a fine wire heating method (hot wire method, manufactured by Kyoto Electronics Industry Co., Ltd., rapid thermal conductivity meter QTM-500). ).

[Transferability]
The composition obtained in each Example and each Comparative Example is a silver-plated electrode of SMD5050 package (I-CHIUN PRECISION INDUSTRY CO., Resin PPA) using a die bonder (manufactured by ASM, AD-830). The parts were quantitatively transferred by stamping, and the workability when an optical semiconductor element (SemiLED, EV-B35A, 35 mil) was mounted thereon was evaluated. When transfer was possible, it was judged as “good”, and when transfer was impossible, it was judged as “bad”.

[Adhesive strength]
The package produced in the transferability evaluation test was heated in an oven at 150 ° C. for 2 hours to cure the silicone resin composition. The die shear strength was measured using a bond tester (manufactured by Dage, Series 4000).

[Bleed]
The package produced in the transferability evaluation test was allowed to stand at 25 ° C. for 1 hour, and then the appearance was visually observed. If no bleeding (bleed out) occurred around the chip, it was judged as “good”, and if it occurred, it was judged as “bad”.

  As shown in Table 2, in Examples 1 to 3 using the silicone resin composition of the present invention, the hardness of the cured product is high, and the component (D) containing an alkoxy group and an alkenyl group is a wetter. By working, even if a high content of the heat conductive filler is blended, the transferability is excellent, there is no bleeding out, and the die bond material is excellent. Further, it was found that these cured products have a high die shear strength of about 20 MPa and a heat conductivity of 1.3 W / m · K or more, which is very excellent in heat dissipation.

  On the other hand, in Comparative Example 1, since the heat conductive filler was small, the thermal conductivity was as low as 0.9 W / m · K. In Comparative Example 2, the heat conductive filler was filled at a high density and the heat conductivity was high. However, since the component (D) of the present invention was not included, the transferability was poor and the LED chip could not be fixed. . In Comparative Example 3, although the component (D) contains an alkoxy group but does not have an alkenyl group, the thermal conductivity is high, but wetter bleedout and die shear strength are reduced, and the appearance and adhesive strength of the product are increased. It was a detrimental result. In Comparative Example 4, the blending amount of the component (B) was as small as 50 parts by mass with respect to a total of 100 parts by mass of the component (A) and the component (B), resulting in inferior die shear strength.

  From these results, the silicone resin composition of the present invention has good workability in the transfer method to the substrate, has no bleed-out, has high adhesive strength, and can give a cured product with high thermal conductivity. It became clear.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and that exhibits the same effects. Are included in the technical scope.

In the average composition formula (1), a, b, c, d, e, f, and g are a ≧ 0, b ≧ 0, c ≧ 0, d ≧ 0, e ≧ 0, f ≧ 0, It is a number satisfying g ≧ 0, b + c + e> 0, e + f + g> 0, and a + b + c + d + e + f + g = 1, a is 0 to 0.65, b is 0 to 0.65, c is 0 to 0.5, d is 0 to 0 Preferably, 0.5, e is 0 to 0.8, f is 0 to 0.8, and g is 0 to 0.6. Further, b + c + e is preferably a number of 0.1 to 0.8, particularly 0.2 to 0.65, and e + f + g is a number of 0.1 to 0.8, particularly 0.2 to 0.6. It is preferable.

Claims (4)

(A) a linear organo having at least two alkenyl groups bonded to a silicon atom in one molecule and having no alkoxy group bonded to a silicon atom and having a viscosity at 25 ° C. of 100 mm ² / s or less Polysiloxane,
(B) Three-dimensional network-like organopolysiloxane represented by the following average composition formula (1), which is waxy or solid at 23 ° C .: for a total of 100 parts by mass of the component (A) and the component (B) 60 to 90 parts by mass,
(R ¹ ₃ SiO _1/2 ) _a (R ² R ¹ ₂ SiO _1/2 ) _b (R ² R ¹ SiO) _c (R ¹ ₂ SiO) _d (R ² SiO _3/2 ) _e (R ¹ SiO _3/2 ) _f (SiO _4/2 ) _g (1)
Wherein R ¹ may be the same or different and is a substituted or unsubstituted monovalent hydrocarbon group having no aliphatic unsaturated bond, R ² is an alkenyl group, a, b, c, d, e, f, and g are respectively a ≧ 0, b ≧ 0, c ≧ 0, d ≧ 0, e ≧ 0, f ≧ 0, g ≧ 0, b + c + e> 0, e + f + g> 0, and a + b + c + d + e + f + g = A number satisfying 1).
(C) Organohydrogenpolysiloxane represented by the following average composition formula (2) and having at least two hydrogen atoms bonded to a silicon atom in one molecule: (A) component, (B) component, and ( D) An amount in which hydrogen atoms bonded to silicon atoms in component (C) are 0.5 to 5.0 times moles of all alkenyl groups bonded to silicon atoms in component,
R ³ _h H _i SiO _{(4-hi) / 2} (2)
Wherein R ³ may be the same or different and is a substituted or unsubstituted monovalent hydrocarbon group having no aliphatic unsaturated bond, and h and i are 0.7 ≦ h ≦ 2.1. , 0.001 ≦ i ≦ 1.0 and 0.8 ≦ h + i ≦ 3.0.)
(D) a linear organopolysiloxane having at least one alkenyl group bonded to a silicon atom in one molecule and having an alkoxy group bonded to a silicon atom at both ends of the molecular chain: the component (A) and the above (B) 3 to 30 parts by mass with respect to 100 parts by mass in total of the components,
(E) Platinum group metal-based catalyst: 1 to 500 ppm in terms of the mass of the catalytic metal element with respect to the total amount of the components (A), (B), (C), and (D), and ( F) Thermally conductive filler having an average particle size of 0.1 μm or more and less than 1 μm: total 30 parts by mass of the component (A), the component (B), the component (C), and the component (D) In contrast, 100 to 300 parts by mass,
A silicone resin composition for die bonding, comprising:   2. The silicone resin composition for die bonding according to claim 1, wherein the component (F) contains one or more selected from zinc oxide and alumina. The silicone resin composition for die bonding according to claim 1 or 2, wherein the component (D) is a siloxane compound represented by the following formula (3).

(In the formula, the arrangement of siloxane repeating units is arbitrary, and m and n are positive numbers satisfying 1 ≦ m ≦ 50 and 0 ≦ n ≦ 100, respectively.)   The hardened | cured material obtained by hardening the silicone resin composition for die bonding as described in any one of Claims 1-3.