JP2017066308A - Resin composition for light emission element encapsulation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition for light emission element encapsulation excellent in gas barrier property.SOLUTION: There is provided a resin composition for light emission element encapsulation containing an organopolysiloxane composition (I) and a filler (II) having an average particle diameter of 10 to 35 μm and an aspect ratio of 55 to 350, with a concentration of the filler (II) to the total solid component of the resin composition of 7.0 to 10.0 vol%.SELECTED DRAWING: None

Description

  The present invention relates to a resin composition for sealing a light emitting device.

  Conventionally, an epoxy resin composition is used as a sealant used to protect a light emitting element such as a light emitting diode (LED) from moisture, dust, and the like in the atmosphere. However, a cured product of the epoxy resin composition has low light resistance, and may be colored due to light deterioration of the light-emitting element due to long-term use. Therefore, various LED sealing agents using a cured product of an organopolysiloxane composition have been proposed (for example, Patent Document 1 and Patent Document 2).

For example, in Patent Document 1, the molar ratio of hydrogen atoms bonded to silicon atoms to alkenyl groups bonded to silicon atoms in the composition is 1.0 or more, and the type A hardness specified in JISK6253 after curing is 20 or less. An LED encapsulant comprising a cured product of a certain curable silicone rubber composition is disclosed. In Patent Document 2, an LED sealing agent obtained by curing the organopolysiloxane composition, the moisture permeability of the sealant, and equal to or less than 50 g / m 2 / ^24h An LED encapsulant is disclosed.

  Although the above-mentioned sealant is excellent in light resistance and heat resistance, it has a drawback that gas permeability is large and sulfur-containing gas existing in a storage environment and a use environment is transmitted. Therefore, the sulfur-containing gas that has passed through the cured product of the organopolysiloxane composition causes the silver-plated surface of the lead frame, which is the substrate of the LED package, to be sulfided and changed to silver sulfide. As a result, the silver-plated surface becomes blackened. There is a problem that

  On the other hand, Patent Document 3 proposes a resin composition for encapsulating an optical semiconductor element in which a glass filler having an anisotropic shape with an aspect ratio of 1.1 to 50 is added to an organopolysiloxane composition, It describes that it has excellent gas barrier properties. However, when this resin composition is used, depending on the type of organopolysiloxane, sedimentation of fillers, piping clogging, defects in the sealant coating skin, etc. may occur.

JP 2007-103494 A JP 2010-265410 A JP 2011-256251 A

  An object of the present invention is to provide a new resin composition for sealing a light emitting device, which is excellent in gas barrier properties.

That is, this invention relates to the following resin composition for light emitting element sealing.
1. A resin composition containing an organopolysiloxane composition (I) and a filler (II) having an average particle diameter of 10 to 35 μm and an aspect ratio of 55 to 350, the solid content of the resin composition being the total amount A resin composition for sealing a light emitting device, wherein the concentration of the filler (II) is 7.0 to 10.0 vol%.
2. The organopolysiloxane composition (I) is (A) a dimethylorganopolysiloxane having at least two alkenyl groups in one molecule, (B) an organohydrodiene polysiloxane having at least two hydrosilyl groups in one molecule, and (C) The resin composition for light emitting element sealing of said claim | item 1 containing a catalyst.
3. Item 3. The resin composition for sealing a light-emitting element according to Item 1 or 2, wherein the concentration of the filler (II) with respect to the total solid content of the resin composition is 8.0 to 9.0 vol%.
4). Item 4. The resin composition for sealing a light-emitting element according to any one of Items 1 to 3, wherein the filler (II) has a flat shape.

  According to the resin composition for sealing a light-emitting element of the present invention, it is possible to provide a resin composition for sealing a light-emitting element excellent in gas barrier properties.

  Hereinafter, the resin composition for sealing a light emitting device according to an embodiment of the present invention will be described in detail.

  The resin composition for sealing a light emitting element is a resin composition containing an organopolysiloxane composition (I) and a filler (II) having an average particle diameter of 10 to 35 μm and an aspect ratio of 55 to 350, The density | concentration of the said filler (II) with respect to the solid content whole quantity of the said resin composition is 7.0-10.0 vol%.

  By using a filler having a predetermined shape and size, the resin composition for sealing a light-emitting element suppresses sedimentation of the filler, clogging of piping, defects in the sealant coating skin, etc. Excellent gas barrier properties when used in Moreover, the resin composition for sealing a light-emitting element is excellent in heat resistance, light resistance, and translucency.

  Here, the gas barrier property is a characteristic that blocks the permeation of gases such as oxygen and water vapor, and that the gas barrier property is good means that it is difficult to pass various gases. Moreover, translucency is the characteristic that the light beam emitted from the light emitting element transmits the sealing agent, and the fact that the light transmissivity is good means that the light beam can be easily transmitted.

  The organopolysiloxane composition (I) includes an organopolysiloxane (A) having at least two alkenyl groups in one molecule, an organohydrodiene polysiloxane (B) having at least two hydrosilyl groups in one molecule, and a catalyst. What contains (C) is preferable from a light-resistant viewpoint.

  The organopolysiloxane (A) is an organopolysiloxane having at least two alkenyl groups in one molecule, and the molecular structure thereof is not particularly limited. For example, linear, branched, cyclic, resinous or partially branched These can be used in combination. The bonding position of the alkenyl group is not limited as long as it is at least two in one molecule, and examples thereof include a molecular chain end and a molecular chain side chain. Examples of the alkenyl group include a vinyl group, an allyl group, a propenyl group, and a butenyl group, and a vinyl group is preferable because it can be easily synthesized.

  Examples of the group other than the alkenyl group in the organopolysiloxane (A) include monovalent hydrocarbon groups other than the alkenyl group, specifically, alkyl groups such as a methyl group, an ethyl group, and a propyl group; a phenyl group, An aryl group such as a tolyl group; an aralkyl group such as a benzyl group or a phenethyl group; a substituted alkyl group such as a chloromethyl group or a 3,3,3-trifluoropropyl group;

  As the organopolysiloxane (A), dimethylorganopolysiloxane in which monovalent hydrocarbon groups other than alkenyl groups are mainly methyl groups is particularly preferable from the viewpoint of heat resistance and light resistance.

  The organohydrodiene polysiloxane (B) is an organopolysiloxane having at least two hydrosilyl groups in one molecule, and its molecular structure is not particularly limited. For example, linear, branched, cyclic, resinous or It is a straight chain having a partial branch, and these may be used in combination.

  As long as there are at least two hydrosilyl groups in one molecule, the bonding position thereof is not limited, and examples thereof include a molecular chain terminal and a molecular chain side chain. Specific examples include organopolysiloxanes having hydrosilyl groups at both ends, organopolysiloxanes having both ends blocked with trimethylsilyl groups, and methylhydrosiloxane-dimethylsiloxane copolymers.

  As the organohydrodiene polysiloxane (B), a methylhydrosiloxane-dimethylsiloxane copolymer is particularly preferable from the viewpoint of heat resistance and light resistance.

  The components (A) and (B) are used in such an amount that the number of hydrosilyl groups in the component (B) is 0.75 to 2.0 per alkenyl group in the component (A). desirable.

  As the catalyst (C), any catalyst known as a hydrosilylation catalyst for organopolysiloxane can be used without particular limitation. Specific examples include metal catalysts such as platinum-based catalysts, palladium-based catalysts, and rhodium-based catalysts, and platinum-based catalysts are particularly preferable from the viewpoint of curability. Examples of the platinum-based catalyst include chloroplatinic acid, alcohol-modified chloroplatinic acid, platinum complexes having a chelate structure, and the like. These can be used alone or in combination of two or more.

  For example, when a platinum catalyst is used, the content of the catalyst (C) is 0.0001 to 1 part by mass with respect to 100 parts by mass of the total solid content of the components (A) and (B) in terms of platinum amount. 0.001 to 0.1 parts by mass is preferable.

  The organopolysiloxane composition (I) includes (A) a dimethylorganopolysiloxane having at least two alkenyl groups in one molecule, (B) an organohydrodiene polysiloxane having at least two hydrosilyl groups in one molecule, and (C) What contains a catalyst is suitable.

  Commercially available products may be used as the organopolysiloxane composition (I). For example, as general commercial products, OE-6630A / B, OE-6336A / B, OE-6351A / B, OE-6250A / B. , EG-6301A / B, JCR-6140A / B, JCR-6125A / B, JCR-6101UP, OE-6450A / B, OE-6520-A / B, OE-6550A / B, OE-6663A / B, OE -6636 A / B, OE-6635 A / B (manufactured by Toray Dow Corning) and the like.

  In these, the liquid A / liquid B has either an alkenyl group or a hydrylsilyl group, and is added in an amount sufficient for the hydrosilylation polymerization curing of the platinum catalyst as the hydrosilylation catalyst.

  The refractive index of the organopolysiloxane composition (I) is preferably in the range of 1.40 to 1.54 from the viewpoint of durability and / or translucency, and is 1.40 to 1.45. It is more preferable to be within the range.

  The filler (II) can be used without particular limitation as long as it has an average particle size of 10 to 35 μm (preferably 10 to 30 μm) and an aspect ratio of 55 to 350 (preferably 55 to 200). As the shape of the filler, a spherical shape, a flat shape, a disc shape, a plate shape, a needle shape, a fiber shape, or a rod shape can be suitably used, and these can be used alone or in combination of two or more. be able to. Especially, it is preferable to use a flat filler from a viewpoint of translucency and / or gas barrier property, and this flat filler may be 0.6 micrometer or less in thickness from a translucent viewpoint. More preferably, it is particularly preferably 0.4 μm or less.

  Here, the aspect ratio is the ratio of the longest dimension to the shortest dimension of the three-dimensional body, for example, the ratio of the longest diameter to the thickness if it is a flat filler, and the fiber diameter if it is a fibrous filler. Is the ratio of length to. A method for measuring the aspect ratio can be appropriately selected according to the shape, and for example, a method of measuring with an electron microscope or the like is preferable.

  The average particle diameter is a particle diameter (D50) at a cumulative volume of 50% of the volume particle size distribution measured by a laser diffraction particle size distribution measuring apparatus.

  The material of the filler (II) is not particularly limited, and examples thereof include inorganic substances, organic substances, and mixtures thereof. Among these, from the viewpoint of translucency, light resistance, strength, linear expansion coefficient, etc., it is a colorless and transparent inorganic substance. Preferably there is. Specific examples include mica, glass flakes, talc, barium sulfate, calcium carbonate, and the like. These can be used alone or in combination of two or more. Of these, glass, mica and talc are preferable, and it is preferable to use at least one selected from glass and mica from the viewpoint of translucency and gas barrier properties, and particularly a refractive index of 1.3 to 2.0. The glass which is in the range is preferable in terms of translucency.

  Further, the difference in refractive index between the organopolysiloxane composition (I) and the filler (II) is preferably 0.5 or less from the viewpoint of translucency (suppression of light scattering), and is 0.35 or less. More preferably, it is particularly preferably 0.2 or less.

  The filler (II) may be subjected to a surface treatment in order to improve wettability with the component (I). Examples of the surface treatment agent include organosilicon compounds such as silane coupling agents, organoalkoxysilanes, organosilazanes, silanols, and alkoxy-containing organopolysiloxanes.

  The concentration of the filler (II) is 7.0 to 10.0 vol%, preferably 8.0 to 9 with respect to the total solid content of the resin composition, from the viewpoints of gas barrier properties, smoothness, and translucency. The range of 0.0 vol% is appropriate.

  If necessary, the resin composition for sealing a light-emitting element may further include, for example, inorganic fine particles other than the above (II), plasticizer, viscosity modifier, flexibility imparting agent, antioxidant, light resistance stabilizer, reaction An inhibitor, an adhesion promoter, etc. can be contained.

  Examples of inorganic fine particles other than the above (II) include silica fine particles, and the silica fine particles having an average particle diameter of 200 nm or less, preferably 5 to 100 nm can be used to settle the filler (II) without deteriorating the gas barrier property. It is preferable from the point which prevents. The silica fine particles may be subjected to a surface treatment in order to improve wettability with the component (I). Examples of the surface treatment agent include organosilicon compounds such as silane coupling agents, organoalkoxysilanes, organosilazanes, silanols, and alkoxy-containing organopolysiloxanes.

  The addition amount of the inorganic fine particles other than the above (II) is 0.1 to 10 mass with respect to 100 mass parts of the solid content of the organopolysiloxane composition (I) from the viewpoint of gas barrier property and prevention of sedimentation of the filler (II). Part, preferably in the range of 0.5 to 5 parts by weight.

  The manufacturing method in particular of the resin composition for sealing a light emitting element is not restrict | limited, It can manufacture by stirring and knead | mixing the said component and other arbitrary components. At that time, if necessary, a mixing apparatus such as a planetary mixer, a loss mixer, and a Hobart mixer, and a kneading apparatus such as a kneader and a three-roll can be used.

  Hereinafter, specific description will be given with reference to examples and reference examples. However, the present invention is not limited to only these examples.

Examples 1-8 and Reference Examples 1-5
<Preparation of resin composition for sealing light emitting device>
OE-6351 (Note 1) Liquid B 100 parts by weight, each filler and the like are added in the composition shown in Table 1 (parts by weight) and uniformly dispersed, and then liquid A 100 parts by weight is added and mixed. An example resin composition for sealing a light emitting device was obtained.

  Details of (Note 1) to (Note 7) in Table 1 are shown below.

In addition, the following glass flakes and mica are fillers (II), and silica fine particles are inorganic fine particles other than filler (II).
(Note 1) “OE-6351”: dimethylorganopolysiloxane resin, trade name, manufactured by Toray Dow Corning Co., Ltd., refractive index 1.41, specific gravity 0.98, A / B mixed at 1/1, catalyst (Note 2) Glass flake A: average particle diameter 25 μm, aspect ratio 63, refractive index 1.57, specific gravity 2.5
(Note 3) Mica: average particle diameter 18 μm, aspect ratio 150, refractive index 1.59, specific gravity 2.9
(Note 4) Glass flake B: average particle diameter 160 μm, aspect ratio 30, refractive index 1.52, specific gravity 2.5
(Note 5) Glass flake C: average particle diameter 15 μm, aspect ratio 3, refractive index 1.52, specific gravity 2.5
(Note 6) “R200”: Silica fine particles, manufactured by Nippon Aerosil Co., Ltd., trade name “Aerosil R200”, particle diameter 12 nm, specific gravity 2.2
(Note 7) “R972”: silica fine particles, manufactured by Nippon Aerosil Co., Ltd., trade name “Aerosil R972”, particle diameter 16 nm, specific gravity 2.2

〔尚、上記配合組成の値は、全て「質量部」である。〕
＜評価試験＞
実施例及び参考例の発光素子封止用樹脂組成物について下記の各評価を行った。結果を表１に併せて示す。

[All the values of the above composition are “parts by mass”. ]
<Evaluation test>
The following evaluation was performed about the resin composition for light emitting element sealing of an Example and a reference example. The results are also shown in Table 1.

Translucency ^{(* 1)}
The following translucency test was evaluated.

  Each composition obtained in the Examples and Reference Examples was applied on a tin plate so as to have a thickness of 300 μm as a dry film, and was heat-cured under conditions of 150 ° C. × 4 hours. Subsequently, the film was peeled off from the tin plate by the mercury amalgam method, and the evaluation free film A (300 μm thickness) was produced.

  Further, using only the dimethylorganopolysiloxane resin (Note 1), an evaluation free film B (300 μm thick) was produced by the same method as described above.

  Next, the total light transmittance of the evaluation free film was measured with “COH-300A” (trade name, color difference / turbidity measuring machine manufactured by Nippon Denshoku Industries Co., Ltd.), and the relative light transmittance was calculated according to the following formula. The rate (%) was calculated.

Relative light transmittance (%) = total light transmittance of evaluation free film A / total light transmittance of evaluation free film B × 100
The evaluation criteria for translucency were as follows.
○: The relative light transmittance is 70% or more, and the translucency is very excellent.
(Triangle | delta): Relative light transmittance is 50% or more and less than 70%, and translucency is excellent.
X: The relative light transmittance is less than 50%, and the translucency is inferior.

Sedimentation ^{(* 2)}
Each composition obtained in Examples and Reference Examples was put in a sealed glass container, and the state after standing at 30 ° C. for 1 day was visually confirmed. In addition, when remarkable sedimentation is recognized by the said sedimentation property test, the use as a uniform resin composition is difficult and may not be used as a product.

The evaluation criteria were as follows.
○: No abnormality at all Δ: Slight sedimentation is observed X: Severe sedimentation is observed

Gas barrier properties ^{(* 3)}
The following moisture permeability test was evaluated.

  In the same manner as described above, an evaluation free film A (300 μm thickness) and an evaluation free film B (300 μm thickness) were produced.

Next, 5 g of calcium chloride (for measuring water content manufactured by Wako Pure Chemical Industries, Ltd.) is placed in a 10 cc glass container (the upper open area is 1.56 cm ² ), and each evaluation free film is adhesive (silicone sealant manufactured by Cemedine). Fix to the upper part of the glass container, let stand for 24 hours in an atmosphere of temperature 40 ° C and humidity 80% RH, calculate the moisture permeability with the following formula, and evaluate the free film B for evaluation as 100 The film A was evaluated by the relative rate (%) of moisture permeability.

Moisture permeability (g / m ² · day) = X / Y
X: Weight difference of free film before and after test (g)
Y: Area of the upper part of the glass container (m ² )
The evaluation criteria were as follows.
○: Less than 50% ×: 50% or more
Smoothness ^{(* 4)}
Using the evaluation free film A created by the translucency test, the smoothness was evaluated according to the following evaluation criteria. In addition, when many unevenness | corrugations are recognized by the said smoothness test, since an unevenness | corrugation generate | occur | produces similarly on the sealing agent surface of a light emitting element, it may not be used as a product.
(Circle): The surface of the evaluation free film A is completely smooth, and the smoothness is very excellent.
(Triangle | delta): Although there are slight unevenness | corrugations on the surface of the evaluation free film A, it is accept | permitted practically.
X: There are many unevenness | corrugations in the surface of the free film A for evaluation, and smoothness is inferior.

Claims (4)

  A resin composition containing an organopolysiloxane composition (I) and a filler (II) having an average particle diameter of 10 to 35 μm and an aspect ratio of 55 to 350, the solid content of the resin composition being the total amount A resin composition for sealing a light emitting device, wherein the concentration of the filler (II) is 7.0 to 10.0 vol%.   The organopolysiloxane composition (I) is (A) a dimethylorganopolysiloxane having at least two alkenyl groups in one molecule, (B) an organohydrodiene polysiloxane having at least two hydrosilyl groups in one molecule, and (C) The resin composition for light emitting element sealing of Claim 1 containing a catalyst.   The resin composition for sealing a light-emitting element according to claim 1 or 2, wherein the concentration of the filler (II) with respect to the total solid content of the resin composition is 8.0 to 9.0 vol%.   The resin composition for light emitting element sealing in any one of Claims 1-3 whose shape of the said filler (II) is flat shape.