JP2020002305A - Composition, sealing member, light-emitting device, lighting apparatus and display device - Google Patents

Abstract

To provide a composition capable of improving light extraction efficiency of a light-emitting device, a sealing member formed by using the composition, a light-emitting device having the sealing member, and a lighting apparatus and a display device including the light-emitting device.SOLUTION: A composition for sealing a light-emitting element is provided, which comprises inorganic oxide particles, a surface modification material at least partially adhered to the inorganic oxide particles, and a silicone resin component, and shows a viscosity of 3.0 Pa s or more and 10.0 Pa s or less at 25°C under a shear velocity of 0.01 (1/s) and a viscosity of 1.0 Pa s or more and 6.0 Pa s or less at 25°C under a shear velocity of 0.1 (1/s).SELECTED DRAWING: Figure 1

Description

  The present invention relates to a composition containing oxide particles to which a surface modifying material is adhered and a silicone resin component, a sealing member, a light emitting device, a lighting device, and a display device.

  Light emitting diodes (LEDs) are widely used as light sources having advantages such as small size, long life, and low voltage driving. An LED chip in an LED package is generally sealed with a sealing material containing a resin in order to prevent contact with a deterioration factor existing in an external environment such as oxygen or moisture. Therefore, the light emitted from the LED chip is transmitted to the outside through the sealing material. Therefore, in order to increase the luminous flux emitted from the LED package, it is important to efficiently extract the light emitted from the LED chip to the outside of the LED package.

  As a sealing material for improving the extraction efficiency of light emitted from the LED chip, an inorganic oxide particle having a dispersed particle size of 1 nm or more and 20 nm or less and a refractive index of 1.8 or more, and a silicone resin (Patent Document 1).

  In this composition, a dispersion containing inorganic oxide particles having a small dispersed particle size and a high refractive index is mixed with a silicone resin. Therefore, the inorganic oxide particles in the dispersion can improve the refractive index of the sealing material, and when light emitted from the LED chip enters the sealing material, the light is emitted at the interface between the LED chip and the sealing material. Total reflection of light can be suppressed. Further, since the dispersed particle size of the inorganic oxide particles is small, a decrease in the transparency of the sealing material is suppressed. As a result, the light extraction efficiency from the LED chip can be improved.

JP 2007-299981 A

  However, when the composition as described above is used as a sealing material, the sealing material and the formed sealing member may have a concave shape, and the light extraction efficiency of the light emitting device is not necessarily sufficient. there were.

  The present invention has been made in order to solve the above problems, and can improve the light extraction efficiency of a light emitting device, a composition, a sealing member formed using the composition, It is an object to provide a light emitting device having a sealing member, and a lighting fixture and a display device provided with the light emitting device.

In order to solve the above problems, according to an aspect of the present invention, an inorganic oxide particles, at least a part of a surface modifying material attached to the inorganic oxide particles, and a silicone resin component,
A viscosity at 25 ° C. and a shear rate of 0.01 (1 / s) is not less than 3.0 Pa · s and not more than 10.0 Pa · s;
Provided is a composition for sealing a light-emitting element, which has a viscosity of 1.0 Pa · s to 6.0 Pa · s at 25 ° C. and a shear rate of 0.1 (1 / s).

  In the above composition, the average primary particle diameter of the inorganic oxide particles may be 3 nm or more and 20 nm or less.

  In the composition, the total content of the inorganic oxide particles and the surface modifying material may be from 0.01% by mass to 2.0% by mass.

According to another embodiment of the present invention, there is provided a sealing member that is a cured product of the composition.
According to another embodiment of the present invention, there is provided a light emitting device including: the sealing member; and a light emitting element sealed by the sealing member.
According to another embodiment of the present invention, there is provided a lighting fixture including the light emitting device.
According to another embodiment of the present invention, there is provided a display device including the light emitting device.

  As described above, according to the present invention, a composition, a sealing member formed using the composition, a light emitting device having the sealing member, and a light emitting device capable of improving the light extraction efficiency of the light emitting device A lighting fixture and a display device provided with the device can be provided.

FIG. 1 is a schematic diagram illustrating an example of a light emitting device according to an embodiment of the present invention.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

<1. Composition>
The composition according to the present embodiment is used for sealing a light emitting element as a sealing member in a light emitting device. That is, the composition according to the present embodiment is a sealing material for sealing the light emitting device. The composition according to the present embodiment contains inorganic oxide particles, a surface modification material at least partially adhered to the inorganic oxide particles, and a silicone resin component.

  The composition has a viscosity of 3.0 Pa · s to 10 Pa · s at a shear rate of 0.01 (1 / s) under a condition of 25 ° C., and a shear rate of 0.1 (1 / s). The viscosity in s) is 1.0 Pa · s or more and 6.0 Pa · s or less. By virtue of the fact that the composition containing the silicone resin component has a viscosity in the above range, when the composition is applied on the light emitting element present in the concave portion of the substrate during formation of the sealing member, the composition exceeds the upper surface of the concave portion. Can be convex. Then, the composition is cured while maintaining the convex shape, and becomes a convex sealing member centering on the light emitting element. Since the sealing member has a convex shape centering on the light emitting element, total reflection on the surface of the sealing member can be reduced, and the light extraction efficiency can be improved.

  It is not clear why the composition containing the silicone resin component has a viscosity in the above range to form a convex sealing member. However, when the viscosity range of the composition is out of the above range, the shape of the sealing member has a height sufficient to suppress total reflection and has a convex shape having a smooth curved surface (spherical surface). Can not. As a result, the light extraction efficiency cannot be increased. In addition, the above-mentioned effects due to the above-mentioned viscosity range are peculiar to the composition containing the silicone resin component, and in the case of a composition using a resin component other than the silicone resin component, the above-mentioned effects due to the above-mentioned viscosity range are not necessarily exhibited. It is not done. The inventors of the present invention have found that a composition containing an inorganic oxide particle to which a surface modifying material is attached and a silicone resin component has a viscosity at a shear rate of 0.01 (1 / s) and a shear rate of 0.1 (1 / s). It has been found that, by setting within a predetermined range, the surface shape of the sealing member can be formed into a convex shape having a smooth curved surface and a sufficient height.

  Further, since the composition containing the silicone resin component has a viscosity in the above range, when the composition is applied on the light emitting element present in the concave portion of the substrate at the time of forming the sealing member, leakage from the concave portion, Air bubbles are prevented from being mixed. This contributes to an improvement in the yield when manufacturing the light emitting device.

The viscosity at a shear rate of 0.01 (1 / s) may be within the above-described range, but is preferably from 3.5 Pa · s to 9.0 Pa · s, more preferably 4.0 Pa · s. s or more and 7.0 Pa · s or less.
The viscosity at a shear rate of 0.1 (1 / s) may be within the range described above, but is preferably from 1.5 Pa · s to 5.0 Pa · s, more preferably 2.0 Pa · s. s or more and 4.0 Pa · s or less.

  The viscosity at a shear rate of 0.01 (1 / s) and the viscosity at a shear rate of 0.1 (1 / s) were measured using a commercially available rheometer (plate-type rotary viscometer) and the shear rate was set to 0.01 ( 1 / s) or 0.1 (1 / s), measuring the shear stress of the composition at a gap of 140 μm and 25 ° C., and calculating based on the measured value of the obtained shear stress. Obtainable.

  The viscosity of the composition varies depending on various factors such as the type and content of the inorganic oxide particles, the surface modification material, and the silicone composition. Therefore, these types and contents may be appropriately adjusted so as to have a predetermined viscosity. Hereinafter, each component that can be included in the composition according to the present embodiment will be described in detail.

(1.1 Inorganic oxide particles)
The inorganic oxide particles scatter light emitted from the light emitting element in a sealing member described later. The inorganic oxide particles improve the refractive index of the sealing member depending on the type. Thus, the inorganic oxide particles contribute to an improvement in the efficiency of extracting light emitted from the light emitting element in the light emitting device.

  The inorganic oxide particles contained in the composition according to the present embodiment are not particularly limited. In the present embodiment, as the inorganic oxide particles, for example, zirconium oxide particles, titanium oxide particles, silica particles, zinc oxide particles, iron oxide particles, copper oxide particles, tin oxide particles, cerium oxide particles, tantalum oxide particles, oxidized Niobium particles, tungsten oxide particles, europium oxide particles, yttrium oxide particles, molybdenum oxide particles, indium oxide particles, antimony oxide particles, germanium oxide particles, lead oxide particles, bismuth oxide particles, and hafnium oxide particles and potassium titanate particles, titanium Barium oxide particles, strontium titanate particles, potassium niobate particles, lithium niobate particles, calcium tungstate particles, yttria stabilized zirconia particles, alumina stabilized zirconia, silica stabilized zirconia, calcia stabilized zirconia Particles, magnesia stabilized zirconia particles, scandia stabilized zirconia particles, hafnia stabilized zirconia particles, ytterbia stabilized zirconia particles, ceria stabilized zirconia particles, india stabilized zirconia particles, strontium stabilized zirconia particles, samarium oxide stabilized zirconia particles Inorganic oxide particles containing at least one selected from the group consisting of gadolinium oxide-stabilized zirconia particles, antimony-added tin oxide particles, and indium-added tin oxide particles are preferably used.

  Among the above, the composition is selected from the group consisting of zirconium oxide particles, titanium oxide particles, and silica particles from the viewpoint of improving transparency and compatibility (affinity) with the sealing resin (silicone resin component). It is preferable to include at least one kind.

  The inorganic oxide particles preferably have a refractive index of 1.7 or more from the viewpoint of improving the refractive index of the sealing member. Examples of such inorganic oxide particles include inorganic oxide particles other than the silica particles described above.

  The inorganic oxide particles are more preferably zirconium oxide particles and / or titanium oxide particles, and particularly preferably zirconium oxide particles.

  The average primary particle diameter of the inorganic oxide particles is, for example, 3 nm or more and 20 nm or less, preferably 4 nm or more and 20 nm or less, more preferably 5 nm or more and 20 nm or less. When the average primary particle diameter is in the above range, a decrease in the transparency of the sealing member can be suppressed. As a result, the efficiency of extracting light from the light emitting element in the light emitting device can be improved.

  The average primary particle size of the inorganic oxide particles can be measured, for example, by observation with a transmission electron microscope. First, the cross section of the cured product of the composition is observed with a transmission electron microscope to obtain a transmission electron microscope image. Next, a predetermined number, for example, 100, of the inorganic oxide particles in the transmission electron microscope image is selected. Then, the longest straight line segment (maximum major axis) of each of these inorganic oxide particles is measured, and the measured values are arithmetically averaged to obtain. The primary particle size of the inorganic oxide particles does not change before and after curing of the composition.

  Here, when the inorganic oxide particles are aggregated, the aggregated particle diameter of the aggregate is not measured. The maximum length of the particles (primary particles) of the inorganic oxide particles constituting the aggregate is measured by a predetermined number, and is set as the average primary particle diameter.

  Also, the content of the inorganic oxide particles in the composition can affect the viscosity characteristics of the composition. Specifically, the content of the inorganic oxide particles in the composition is, for example, 0.005% by mass or more and 1.3% by mass or less, preferably 0.05% by mass or more and 1.0% by mass or less, more preferably , 0.1 mass% or more and 0.8 mass% or less. Thereby, the effect of improving the light extraction efficiency by the inorganic oxide particles can be sufficiently obtained, and at the same time, the viscosity of the composition can be more reliably set within the above range. On the other hand, when the content of the inorganic oxide particles in the composition exceeds 1.3% by mass, depending on the type of the silicone resin component contained in the composition, the shear rate at a shear rate of 0.01 (1 / s) is obtained. The viscosity and the viscosity at a shear rate of 0.1 (1 / s) may increase and exceed the above-mentioned range.

  The surface modification material described below is attached to the surface of the inorganic oxide particles described above. Thereby, the inorganic oxide particles are stably dispersed in the composition.

(1.2 Surface modification material)
The composition according to the present embodiment includes a surface modification material. In the composition, at least a part of the surface modification material adheres to the surface of the inorganic oxide particles to prevent aggregation of the inorganic oxide particles. Further, the compatibility with the silicone resin component is improved.

  Here, "adhering" the surface-modifying material to the inorganic oxide particles means that the surface-modifying material contacts or bonds to the inorganic oxide particles by an interaction or reaction between them. Examples of the contact include physical adsorption. Examples of the bond include an ionic bond, a hydrogen bond, and a covalent bond.

Such a surface modification material is not particularly limited as long as it can adhere to the inorganic oxide particles and has good compatibility with the silicone resin component.
As such a surface modification material, a surface modification material having at least one functional group selected from the group of a reactive functional group, for example, an alkenyl group, an H-Si group, and an alkoxy group is suitably used.

As the alkenyl group, for example, a linear or branched alkenyl group having 2 to 5 carbon atoms can be used, and specific examples include a vinyl group, a 2-propenyl group, and a prop-2-en-1-yl group. Can be
Examples of the alkoxy group include a linear or branched alkoxy group having 1 to 5 carbon atoms, and specific examples include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, and a butoxy group.

  Examples of the surface modifying material having at least one functional group selected from the group consisting of an alkenyl group, an H-Si group, and an alkoxy group include, for example, the following silane compounds, silicone compounds, and carbon-carbon unsaturated bond-containing fatty acids. These can be used alone or in combination of two or more.

  As the silane compound, for example, vinyltrimethoxysilane, isobutyltrimethoxysilane, phenyltrimethoxysilane, methacryloxypropyltrimethoxysilane, acryloxypropyltrimethoxysilane, dimethylchlorosilane, methyldichlorosilane, diethylchlorosilane, ethyldichlorosilane, Methylphenylchlorosilane, diphenylchlorosilane, phenyldichlorosilane, trimethoxysilane, dimethoxysilane, monomethoxysilane, triethoxysilane, diethoxymonomethylsilane, monoethoxydimethylsilane, methylphenyldimethoxysilane, diphenylmonomethoxysilane, methylphenyldiethoxy Silane, and diphenylmonoethoxysilane.

Examples of the silicone compound include methyl hydrogen silicone, methyl phenyl hydrogen silicone, diphenyl hydrogen silicone, phenyl silicone at both ends of alkoxy, methyl phenyl silicone, methyl phenyl silicone at both ends of alkoxy, methyl phenyl silicone containing alkoxy group, and containing alkoxy group. Examples include dimethyl silicone, alkoxy one terminal trimethyl one terminal (methyl group one terminal) dimethyl silicone, and alkoxy group-containing phenyl silicone.
The silicone compound may be an oligomer or a resin (polymer).
Examples of the carbon-carbon unsaturated bond-containing fatty acid include methacrylic acid and acrylic acid.

  Among these surface-modifying materials, vinyltrimethoxysilane, isobutyltrimethoxysilane, phenyltrimethoxysilane, and the like are preferable in terms of suppressing aggregation of inorganic oxide particles in the composition and easily obtaining a highly transparent sealing member. Methoxysilane, alkoxy one terminal vinyl one terminal methylphenyl silicone, alkoxy one terminal vinyl one terminal phenyl silicone, alkoxy one terminal vinyl one terminal dimethyl silicone, alkoxy one terminal trimethyl one terminal dimethyl silicone, methoxy group-containing phenyl silicone, and methyl phenyl silicone It is preferable to use one or more selected from the group consisting of

  From the viewpoint of adjusting the viscosity to a predetermined range, it is preferable to perform surface modification with both a silane compound and a silicone compound. That is, the composition preferably contains at least one silane compound and at least one silicone compound. Preferred silane compounds include, for example, vinyltrimethoxysilane, isobutyltrimethoxysilane, and phenyltrimethoxysilane. Preferred silicone compounds include dimethyl silicone at one terminal of trimethyl at one terminal of alkoxy, phenyl silicone containing methoxy group, and methyl phenyl silicone.

  Since the surface modifying material affects the dispersion stability of the inorganic oxide particles in the composition, the amount of the surface modifying material with respect to the inorganic oxide particles can affect the viscosity characteristics of the composition. The amount of the surface modification material with respect to the inorganic oxide particles is preferably from 50% by mass to 200% by mass, more preferably from 50% by mass to 150% by mass, and further preferably from 80% by mass to 120% by mass. It is as follows. Thereby, the inorganic oxide particles can be uniformly dispersed in the composition, and at the same time, the viscosity of the composition can be more reliably set within the above range. When the amount of the surface modifying material relative to the inorganic oxide particles is less than 50% by mass, the viscosity and the shear at a shear rate of 0.01 (1 / s) may be determined depending on the combination and content of the silicone resin component and the inorganic oxide particles. The viscosity at a speed of 0.1 (1 / s) may increase and exceed the above range.

The total content of the inorganic oxide particles and the surface modification material in the composition of the present embodiment is preferably 0.01% by mass or more and 2.0% by mass or less, more preferably 0.05% by mass. It is 1.5 mass% or less, More preferably, it is 0.1 mass% or more and 1.2 mass% or less.
When the total content of the inorganic oxide particles and the surface modifying material is in the above range, the composition having a desired viscosity can be easily adjusted.

(1.3 Silicone resin component)
The silicone resin component is a main component in the composition according to the present embodiment. When the composition according to the present embodiment is used as a sealing material, the silicone resin component cures and seals the light emitting element, so that deterioration factors from the external environment such as moisture and oxygen reach the light emitting element. To prevent that. Further, in the present embodiment, the cured product obtained from the silicone resin component is basically transparent and can transmit light emitted from the light emitting element.

  Such a resin component is not particularly limited as long as it is a silicone resin that can be used as a sealing material. As the silicone resin, for example, a dimethyl silicone resin, a methylphenyl silicone resin, a phenyl silicone resin, an organically modified silicone resin, or the like can be used.

  In particular, when a surface-modifying material having at least one functional group selected from the group consisting of an alkenyl group, an H-Si group, and an alkoxy group is used as the surface-modifying material, the silicone resin is made of H-Si It is preferable to use a silicone resin having at least one functional group selected from the group consisting of a group, an alkenyl group, and an alkoxy group. The reason will be described below.

  The alkenyl group of the surface modification material crosslinks by reacting with the H-Si group in the silicone resin. The H-Si group of the surface modification material crosslinks by reacting with the alkenyl group in the silicone resin. The alkoxy group of the surface modification material condenses with the alkoxy group in the silicone resin through hydrolysis. By such bonding, the silicone resin and the surface modifying material are integrated, so that the strength and denseness of the obtained sealing member can be improved.

The structure of the silicone resin component may be a two-dimensional chain structure, a three-dimensional network structure, or a cage structure.
The silicone resin component only needs to be in the form of a polymer that has been cured when used as a sealing member, and may be in a state before curing, that is, a precursor, in the composition. Therefore, the silicone resin component present in the composition may be a monomer, an oligomer, or a polymer.

  As the silicone resin component, an addition reaction type, a condensation reaction type, or a radical polymerization reaction type may be used.

  The viscosity of the silicone resin component at 25 ° C. measured in accordance with JIS Z 8803: 2011 is, for example, 0.1 Pa · s to 100 Pa · s, preferably 1 Pa · s to 50 Pa · s, more preferably 2 Pa · s. S or more and 10 Pa · s or less. Thereby, the viscosity characteristics of the composition can be easily controlled, and the viscosity of the composition can be more reliably set within the above range. On the other hand, when the viscosity of the silicone resin component is less than 0.1 Pa · s, the viscosity and the shear rate at a shear rate of 0.01 (1 / s) depend on the types and contents of the inorganic oxide particles and the surface modification material. The viscosity at 0.1 (1 / s) decreases and may not satisfy the above range. Further, if the viscosity of the silicone resin component exceeds 100 Pa · s, the viscosity at a shear rate of 0.01 (1 / s) and the shear rate of 0.1 (1 / s) may depend on the types and contents of the inorganic oxide particles and the surface modification material. In some cases, the viscosity at 1 / s) increases and exceeds the above-mentioned range.

  The content of the resin component in the composition according to the present embodiment can be the balance of other components, and is, for example, 80% by mass or more and 99.9% by mass or less.

  Further, the composition according to the present embodiment may include phosphor particles as long as the object of the present invention is not impaired. The phosphor particles absorb light of a specific wavelength emitted from the light emitting element and emit light of a predetermined wavelength. That is, the conversion of the wavelength of light and the adjustment of the color tone can be performed by the phosphor particles.

The phosphor particles are not particularly limited as long as they can be used in a light emitting device as described below, and can be appropriately selected and used so that the light emitting device emits a desired color.
The content of the phosphor particles in the composition of the present embodiment can be appropriately adjusted and used so as to obtain a desired brightness.

  Further, the composition of the present embodiment includes a preservative, a polymerization initiator, a polymerization inhibitor, a curing catalyst, a curing agent, an antioxidant, a light diffusing agent and the like, as long as the object of the present invention is not impaired. May be contained. It is preferable to use silica particles having an average particle diameter of 1 to 30 μm as the light diffusing agent.

  Further, the composition of the present embodiment may include components and by-products used during production as long as the object of the present invention is not impaired. Examples of such a component include a dispersion medium used at the time of dispersing inorganic oxide particles or at the time of surface modification with a surface modification material. In particular, the dispersion medium can affect the viscosity properties of the composition. On the other hand, it is preferable to remove the composition as much as possible, since it may cause bubbles when the composition is cured.

  The method for preparing the composition of the present embodiment described above is not limited, and can be obtained by mixing the inorganic resin particles to which the surface modifying material is adhered and the silicone resin component.

  Examples of a method of attaching the surface modifying material to the inorganic oxide particles include, for example, a dry method in which the surface modifying material is directly mixed with the inorganic oxide particles, spraying, and the like, or a method in which the inorganic oxide particles are dispersed in a dispersion medium in which the surface modifying material is dissolved. There is a wet method in which the dispersion is charged and the surface is modified in a solvent to obtain a dispersion.

  In addition, when mixing the silicone resin component with the dispersion containing the inorganic oxide particles to which the surface modifying material has adhered, it is preferable to remove the dispersion medium contained in the dispersion. However, it may be contained in the composition as long as it does not inhibit the present invention.

  According to the embodiment described above, the composition containing the silicone resin component has a viscosity in a predetermined range at a shear rate of 0.01 (1 / s) and a shear rate of 0.1 (1 / s), When the composition is applied to the light emitting element at the time of forming the sealing member, the composition becomes convex. Then, the composition is cured while maintaining the convex shape, and becomes a convex sealing member centering on the light emitting element. In addition, the convex surface of the sealing member thus formed has a sufficient height and a smooth curved surface, so that total reflection of light from the light emitting element can be suppressed. Therefore, the efficiency of extracting light from the light emitting device is improved.

<2. Sealing member>
The sealing member according to the present embodiment is a cured product of the composition according to the present embodiment. The sealing member according to the present embodiment is generally used as a sealing member disposed on a light emitting element or a part thereof.

  The sealing member according to the present embodiment can be manufactured by curing the composition according to the present embodiment as described above. The method for curing the composition can be selected according to the characteristics of the resin component in the composition according to the present embodiment, and examples thereof include heat curing and electron beam curing. More specifically, the sealing member of the present embodiment is obtained by curing the resin component in the composition of the present embodiment by an addition reaction or a polymerization reaction.

  Note that when performing thermosetting, it is preferable to heat the substrate and send gas (for example, air) from above or from the side of the substrate with respect to the composition applied on the substrate. As a result, convection occurs in the composition, and the inorganic oxide particles are likely to be unevenly distributed on the peripheral portion of the sealing member and the air interface. And the viscosity rises in the peripheral part and air interface part of the sealing member in which such inorganic oxide particles are unevenly distributed, and the fluidity of the resin on the substrate of the composition becomes poor. As a result, the surface of the sealing member has a sufficient height and is likely to have a smooth curved convex shape.

  The thickness and shape of the sealing member according to the present embodiment can be appropriately adjusted according to desired applications and characteristics, and are not particularly limited. In addition, the sealing member according to the present embodiment is obtained by applying the composition according to the present embodiment onto a light emitting element and curing the composition. It can have a shape that is convex enough to suppress total reflection sufficiently.

  The average dispersed particle diameter of the inorganic oxide particles in the sealing member is preferably from 10 nm to 200 nm, more preferably from 20 nm to 150 nm, and still more preferably from 40 nm to 130 nm.

  When the average dispersed particle size is 10 nm or more, a sufficient light scattering effect can be obtained, and the light extraction efficiency of the light emitting device can be further improved. On the other hand, when the average dispersed particle size is 200 nm or less, the transmittance of the sealing member can be appropriately increased, and the light extraction efficiency of the light emitting device can be further improved.

  The average dispersed particle size of the inorganic oxide particles in the sealing member is a number distribution-based average particle size (median diameter, D50) measured by transmission electron microscope observation (TEM) of the sealing member. . In addition, the average dispersed particle size of the inorganic oxide particles in the sealing member according to the present embodiment is a value measured and calculated based on the dispersed particle size of the inorganic oxide particles in the sealing member. The average dispersed particle diameter is measured and calculated based on the diameter of the dispersed inorganic oxide particles, regardless of whether the inorganic oxide particles are dispersed in primary particles or secondary particles. . In the present embodiment, the D50 of the inorganic oxide particles in the sealing member may be measured as the D50 of the inorganic oxide particles to which the surface modification material has adhered. In the sealing member, there may be inorganic oxide particles to which the surface modification material is attached, and inorganic oxide particles to which the surface modification material is not attached. D50 is measured as a value in these mixed states.

  Since the sealing member according to the present embodiment is a cured product of the composition according to the present embodiment, when the light emitting element is sealed, the sealing member has a convex shape that can sufficiently suppress total reflection around the light emitting element. I can do it. Therefore, according to the present embodiment, the efficiency of extracting light emitted from the light emitting element when used as a sealing member can be improved. In particular, by setting the average primary particle diameter of the inorganic oxide particles to be 3 nm or more and 20 nm or less, it is possible to obtain a sealing member having more excellent light extraction efficiency.

<3. Light-emitting device>
Next, the light emitting device according to the present embodiment will be described. The light emitting device according to the present embodiment includes the above-described sealing member and a light emitting element sealed with the sealing member.
Examples of the light emitting element include a light emitting diode (LED) and an organic light emitting diode (OLED). In particular, the sealing member according to the present embodiment is suitable for sealing a light emitting diode.

  Hereinafter, the light emitting device according to the present embodiment will be described using an example in which the light emitting element is a light emitting diode on a chip, that is, an LED chip, and the light emitting device is an LED package. FIG. 1 is a schematic diagram (cross-sectional view) illustrating an example of a light emitting device according to an embodiment of the present invention. It should be noted that the size of each member in the drawings is appropriately emphasized for ease of explanation, and does not indicate the actual dimensions and the ratio between the members.

  A light emitting device (LED package) 1 shown in FIG. 1 includes a substrate 2 having a concave portion 21, a light emitting element (LED chip) 3 arranged on the bottom surface of the concave portion 21 of the substrate 2, and the light emitting element 3 covering the concave portion 21. And a sealing member 4 for sealing as described above.

  The sealing member 4 is configured by the above-described sealing member according to the present embodiment. Therefore, when the composition is applied to the concave portion 21, the composition can be convex beyond the upper edge of the concave portion 21. Conventionally, even when the conventional composition is applied to the concave portion 21, it has been difficult for the conventional composition to leak out from the upper edge portion of the concave portion 21 and to form a convex shape enough to sufficiently suppress total reflection.

  In the present embodiment, the light extraction efficiency of the light emitting device 1 is improved by making the surface 41 of the sealing member 4 convex as described above. Further, in the sealing member 4, inorganic oxide particles are dispersed. Therefore, the light emitted from the light emitting element 3 is scattered by the inorganic oxide particles, and as a result, the light extraction efficiency is improved. Further, in the sealing member 4, the phosphor particles 5 are dispersed. The phosphor particles 5 convert at least a part of the wavelength of the light emitted from the light emitting element 3.

  The light emitting device according to the present invention is not limited to the illustrated embodiment. For example, the light emitting device according to the present invention may not include the phosphor particles in the sealing member. Further, the sealing member according to the present embodiment can be present at an arbitrary position in the sealing member. Further, in one embodiment of the present invention, the sealing member is composed of a plurality of layers, and the constitutions of these layers may be the same or different. In this case, at least one of the layers is constituted by the sealing member according to the present embodiment.

  As described above, the light emitting device according to the present embodiment is excellent in light extraction efficiency because the light emitting element is sealed by the sealing member of the present embodiment.

  In the light emitting device according to the embodiment, the light emitting element is sealed with the composition according to the embodiment as described above. Therefore, in one aspect, the present invention also relates to a method for manufacturing a light-emitting device including a step of sealing a light-emitting element using the composition according to the present embodiment.

  The light emitting device according to the embodiment as described above can be used for, for example, a lighting fixture and a display device. Therefore, the present invention, in one aspect, relates to a lighting device or a display device including the light-emitting device according to the present embodiment.

Illumination equipment includes, for example, general lighting devices such as indoor lights and outdoor lights, and lighting of switch units of electronic devices such as mobile phones and OA devices.
Since the lighting fixture according to the present embodiment includes the light emitting device according to the present embodiment, even when the same light emitting element is used, the luminous flux emitted is larger than in the related art, and the surrounding environment can be made brighter. it can.

Examples of the display device include a mobile phone, a portable information terminal, an electronic dictionary, a digital camera, a computer, a television, and peripheral devices thereof.
Since the display device according to the present embodiment includes the light-emitting device according to the present embodiment, even if the same light-emitting element is used, the emitted light flux is larger than that of the related art, and for example, a clearer and brighter display is provided. It can be performed.

  Hereinafter, the present invention will be described in more detail with reference to examples. The embodiments described below are merely examples of the present invention, and do not limit the present invention.

[Example 1]
(Preparation of dispersion liquid)
20 parts by mass of zirconium oxide particles having an average primary particle diameter of 5 nm (manufactured by Sumitomo Osaka Cement), 60 parts by mass of toluene, and 2.5 parts by mass of isobutyltrimethoxysilane (manufactured by SIGMA-ALDRICH, product name 444065) as a surface modification material Parts, 2.5 parts by mass of phenyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., product name KBM103) and 10 parts by mass of methylphenyl silicone (manufactured by Shin-Etsu Chemical Co., Ltd., product name: KR-213) were added and mixed. The mixed solution was subjected to a dispersion treatment for 6 hours using a bead mill, and then the beads were removed.

5.0 parts by mass of vinyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-1003) was added to the dispersion after removing the beads. Next, this mixture was stirred at 110 ° C. for 10 hours under reflux with toluene to obtain a dispersion surface-modified with silane and siloxane.
The amount of the surface modifying material based on the zirconium oxide particles was 100% by mass.

(Preparation of composition)
1.0 part by mass of the obtained dispersion was 99.6 parts by mass of a silicone resin ("OE-6630 (A solution: B solution = 1: 4)" manufactured by Dow Corning Toray Co., Ltd., viscosity: 2.5 Pa.s). Parts were mixed. Then, toluene was removed from the mixed solution by an evaporator to obtain a composition according to Example 1 containing zirconium oxide particles to which a surface modifying material was adhered and a silicone resin (OE-6630).
The total content of the zirconium oxide particles and the surface modifying material in the composition was 0.4% by mass.

(Evaluation of viscosity of composition)
The viscosity of the obtained composition according to Example 1 was measured using a rheometer (Rheostress RS-6000, manufactured by HAAKE). The viscosity was measured at a temperature of 25 ° C., with the shear rates set to 0.01 (1 / s) and 0.1 (1 / s).
As a result, the viscosity at a shear rate of 0.01 (1 / s) was 4.5 Pa · s, and the viscosity at a shear rate of 0.01 (1 / s) was 2.9 Pa · s.

(Production of LED package)
The obtained composition was mixed with phosphor particles (YAG) and filled into an LED lead frame with a thickness of 300 μm. Then, it was kept at room temperature for 3 hours. Next, the composition was slowly heated and cured to form a sealing member, and a white LED package according to Example 1 was produced. About the obtained white LED package, the shape of the sealing member and the luminous efficiency of the white LED package were evaluated as follows.

(Shape of sealing member)
The shape of the sealing member was confirmed by an optical microscope equipped with a 3D display function (manufactured by Keyence Corporation, product name: VHX-900F). Then, the shape of the surface of the sealing member was evaluated according to the following criteria. As a result, the surface shape of the sealing member of the LED package according to Example 1 was convex.
Convex: The surface of the sealing member exists at a position higher than the upper surface of the lead frame.
Flat: The surface of the sealing member is present at the same position as the upper surface of the lead frame.
Concave: The surface of the sealing member is present at a position lower than the upper surface of the lead frame.

(Luminous efficiency)
The luminous efficiency was measured by applying a voltage of 3 V and a current of 150 mA to the LED package using a total luminous flux measurement system (manufactured by Otsuka Electronics Co., Ltd.). As a result, the luminous efficiency of the LED package according to Example 1 was 107.6 lm / W.

[Example 2]
(Preparation of dispersion liquid)
A dispersion was obtained in the same manner as in Example 1 except that zirconium oxide particles having an average primary particle diameter of 12 nm (manufactured by Sumitomo Osaka Cement) were used instead of using zirconium oxide particles having an average primary particle diameter of 5 nm. .

(Preparation of composition)
1.9 parts by mass of the obtained dispersion was mixed with 99.2 parts by mass of a silicone resin (OE-6630, manufactured by Dow Corning Toray Co., Ltd.). Then, toluene was removed from the mixed solution by an evaporator to obtain a composition according to Example 2 containing zirconium oxide particles to which a surface modifying material was attached and a silicone resin (OE-6630).
The total content of the zirconium oxide particles and the surface modifying material in the composition was 0.8% by mass.

(Evaluation of composition)
The viscosity of the composition was evaluated in the same manner as in Example 1. As a result, the viscosity at a shear rate of 0.01 (1 / s) was 5.1 Pa · s, and the viscosity at a shear rate of 0.1 (1 / s) was 3.5 Pa · s.

(Production of LED package)
Using the composition according to Example 2, an LED package according to Example 2 was produced in the same manner as in Example 1. When the shape of the sealing member and the luminous efficiency of the LED package were evaluated for the obtained LED package in the same manner as in Example 1, the shape of the sealing member of the LED package according to Example 2 was convex, The efficiency was 111.8 lm / W.

[Comparative Example 1]
A composition according to Comparative Example 1 was obtained in the same manner as in Example 1 except that 24.2 parts by mass of the dispersion prepared in Example 1 and 90.3 parts by mass of the silicone resin (OE-6630) were used. .
The total content of the zirconium oxide particles and the surface modifying material in the composition was 9.7% by mass.

  The viscosity of the composition was evaluated in the same manner as in Example 1. As a result, the viscosity at a shear rate of 0.01 (1 / s) was 25.8 Pa · s, and the viscosity at a shear rate of 0.1 (1 / s) was 15.3 Pa · s.

Using the composition according to Comparative Example 1, an LED package according to Comparative Example 1 was produced in the same manner as in Example 1. When the shape of the sealing member and the luminous efficiency of the LED package were evaluated for the obtained LED package in the same manner as in Example 1, the shape of the sealing member of the LED package according to Comparative Example 1 was flat, and The efficiency was 105.7 lm / W.
[Comparative Example 2]
A composition according to Comparative Example 2 was obtained in the same manner as in Example 2 except that 19.4 parts by mass of the dispersion prepared in Example 2 and 92.3 parts by mass of the silicone resin (OE-6630) were used. .
The total content of the zirconium oxide particles and the surface modifying material in the composition was 7.7% by mass.

  The viscosity of the composition was evaluated in the same manner as in Example 1. As a result, the viscosity at a shear rate of 0.01 (1 / s) was 12.5 Pa · s, and the viscosity at a shear rate of 0.1 (1 / s) was 5.6 Pa · s.

  Using the composition according to Comparative Example 2, an LED package according to Comparative Example 2 was produced in the same manner as in Example 1. When the shape of the sealing member and the luminous efficiency of the LED package were evaluated for the obtained LED package as in Example 1, the shape of the sealing member of the LED package according to Comparative Example 2 was concave, and the luminous efficiency was low. Was 104.1 lm / W.

[Comparative Example 3]
(Preparation of composition)
Instead of using 6.6 parts by mass of the dispersion of Example 1 and using OE-6630, 97.4 parts by mass of silicone resin (OE-6520 manufactured by Dow Corning Toray Co., Ltd. (solution A: solution B = 1: 1)) A composition according to Comparative Example 3 was obtained in the same manner as in Example 1, except for using parts.
The total content of the zirconium oxide particles and the surface modifying material in the composition was 2.6% by mass.
The viscosity of the composition was evaluated in the same manner as in Example 1. As a result, the viscosity at a shear rate of 0.01 (1 / s) was 2.1 Pa · s, and the viscosity at a shear rate of 0.1 (1 / s) was 0.9 Pa · s.

  Using the composition according to Comparative Example 3, an LED package according to Comparative Example 3 was produced in the same manner as in Example 1. When the shape of the sealing member and the luminous efficiency of the LED package were evaluated for the obtained LED package in the same manner as in Example 1, the shape of the sealing member of the LED package according to Comparative Example 3 was concave, and the luminous efficiency was Was 102.5 lm / W.

[Comparative Example 4]
(Preparation of dispersion liquid)
20 parts by mass of zirconium oxide particles having an average primary particle diameter of 5 nm (manufactured by Sumitomo Osaka Cement Co., Ltd.), 72 parts by mass of toluene, and 1.0 mass of isobutyltrimethoxysilane (manufactured by SIGMA-ALDRICH, product name 444065) as a surface modification material 1.0 part by mass of phenyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., product name KBM103) and 4.0 parts by mass of methylphenyl silicone resin (manufactured by Shin-Etsu Chemical Co., Ltd., product name: KR-213) were added and mixed. . The mixed solution was subjected to a dispersion treatment for 6 hours using a bead mill, and then the beads were removed.

2.0 parts by mass of vinyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-1003) was added to the dispersion after removing the beads. Next, this mixture was stirred at 110 ° C. for 10 hours under reflux with toluene to obtain a dispersion surface-modified with silane and siloxane.
The amount of the surface modifying material based on the zirconium oxide particles was 40% by mass, which was smaller than that of the dispersion of Example 1.

(Preparation of composition)
7.1% by mass of the obtained dispersion was mixed with 98.0 parts by mass of a silicone resin (OE-6630, manufactured by Dow Corning Toray). Then, toluene was removed from the mixed solution by an evaporator to obtain a composition according to Comparative Example 4 containing zirconium oxide particles to which a surface modifying material was attached and a silicone resin (OE-6630).
The total content of the zirconium oxide particles and the surface modifying material in the composition was 2.0% by mass.

(Evaluation of composition)
The viscosity of the composition was evaluated in the same manner as in Example 1. As a result, the viscosity at a shear rate of 0.01 (1 / s) was 18.2 Pa · s, and the viscosity at a shear rate of 0.1 (1 / s) was 10.8 Pa · s.

(Production of LED package)
Using the composition according to Comparative Example 4, an LED package according to Comparative Example 4 was produced in the same manner as in Example 1. When the shape of the sealing member of the obtained LED package was evaluated in the same manner as in Example 1, the shape of the sealing member of the LED package according to Example 4 was convex, but wrinkles occurred on the surface. Was. When the luminous efficiency of the LED package was evaluated in the same manner as in Example 1, the luminous efficiency of the LED package according to Example 4 was 99.4 lm / W.
Table 1 summarizes the above results.

  From the results of Examples 1 and 2 and Comparative Examples 1 to 4, the viscosity at a shear rate of 0.01 (1 / s) is 3.0 Pa · s or more and 10.0 Pa · s or less, and the shear rate is 0.1 Pa · s or less. If the composition has a viscosity at 1 (1 / s) of 1.0 Pa · s or more and 6.0 Pa · s or less, a sealing member having a convex surface can be formed, and total reflection on the surface of the sealing member can be reduced. It was shown that the luminous efficiency of the obtained light emitting device (LED package) can be improved by suppressing the luminous efficiency.

  According to the results of Comparative Example 4, even at a composition in which the surface shape of the sealing member is convex, the viscosity at a shear rate of 0.01 (1 / s): not less than 3.0 Pa · s and not more than 10.0 Pa · s. Further, it was confirmed that a composition not satisfying the viscosity at a shear rate of 0.1 (1 / s): 1.0 Pa · s or more and 6.0 Pa · s or less had low luminous efficiency. This is because the composition of Comparative Example 4 had a small amount of the surface modification material and a large viscosity, and thus wrinkles were generated on the surface of the formed sealing member, whereby total reflection was not sufficiently suppressed. Can be considered. Furthermore, since the amount of the surface modification material in the dispersion of Comparative Example 4 was small, the compatibility between the inorganic oxide particles and the silicone resin component became poor, and it was also assumed that the transparency of the sealing member was lowered.

(Evaluation of the yield of LED package fabrication)
Using the compositions of Examples 1 and 2 and Comparative Examples 1 to 3, LED packages were manufactured five times.

  As a result, when the compositions of Examples 1 and 2 were used, an LED package could be manufactured without any problem five times.

  However, in the composition of Comparative Example 1, air bubbles were sometimes mixed as a result of the viscosity of the composition being too high. Further, the compositions of Comparative Examples 2 and 3 sometimes leaked from the cup of the lead frame.

  From these results, the viscosity at a shear rate of 0.01 (1 / s) is not less than 3.0 Pa · s and not more than 10.0 Pa · s, and the viscosity at a shear rate of 0.1 (1 / s) is 1. It was also shown that the use of a composition having a pressure of 0 Pa · s or more and 6.0 Pa · s or less improves the yield of light-emitting devices (LED packages).

  As described above, the preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to such examples. It is apparent that those skilled in the art to which the present invention pertains can conceive various changes or modifications within the scope of the technical idea described in the appended claims. It is understood that these also belong to the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Light-emitting device 2 Substrate 21 Depression 3 Light-emitting element 4 Sealing member 41 Surface 5 Phosphor particle

Claims (7)

Inorganic oxide particles, at least a part of a surface modifying material adhered to the inorganic oxide particles, and a silicone resin component,
A viscosity at 25 ° C. and a shear rate of 0.01 (1 / s) is not less than 3.0 Pa · s and not more than 10.0 Pa · s;
A composition for sealing a light-emitting element, which has a viscosity at 25 ° C. and a shear rate of 0.1 (1 / s) of 1.0 Pa · s or more and 6.0 Pa · s or less.   The composition according to claim 1, wherein the average primary particle diameter of the inorganic oxide particles is 3 nm or more and 20 nm or less.   A composition for sealing a light-emitting element, wherein the total content of the inorganic oxide particles and the surface modifying material is 0.01% by mass or more and 2.0% by mass or less.   A sealing member, which is a cured product of the composition according to claim 1.   A light emitting device comprising: the sealing member according to claim 4; and a light emitting element sealed by the sealing member.   A lighting fixture comprising the light emitting device according to claim 5. A display device comprising the light emitting device according to claim 5.

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