WO2014091762A1

WO2014091762A1 - Sealant for led device and led device using same

Info

Publication number: WO2014091762A1
Application number: PCT/JP2013/007334
Authority: WO
Inventors: 後藤　賢治
Original assignee: コニカミノルタ株式会社
Priority date: 2012-12-14
Filing date: 2013-12-12
Publication date: 2014-06-19
Also published as: JPWO2014091762A1

Abstract

The present invention addresses the problem of providing a sealant for a light-emitting diode (LED) device, and an LED device using the same, that has low deformation and can form a compact film. In order to solve this problem, a sealant for an LED device is provided that comprises a polysiloxane compound, a silane coupling agent, and metal oxide fine particles. The solid silicon nuclear magnetic resonance spectrum of a cured film, cured by holding the sealant for an LED device at 65°C for twelve hours and then at 150°C for three hours, has a peak in which the peak top position is in a region where a chemical shift is in the range −120 ppm to −90 ppm and in which a half value width is greater than 5.0 ppm and no more than 12 ppm, and a peak in which the peak top position is in a region where a chemical shift is in the range −80 ppm to −40 ppm and a half value width is greater than 5.0 ppm and no more than 12 ppm, and the silanol content of the cured film is greater than 10% by mass and no more than 30% by mass.

Description

Sealant for LED device and LED device using the same

The present invention relates to an LED device sealant and an LED device using the same.

Recently, a white LED device in which a phosphor such as a YAG phosphor is arranged in the vicinity of a gallium nitride (GaN) blue LED (Light Emitting Diode) chip has been proposed. In the white LED device, the blue light emitted from the blue LED chip and the yellow light emitted from the phosphor in response to the blue light are mixed to obtain white light. A white LED device in which various phosphors are arranged in the vicinity of the blue LED chip has also been developed. In the white LED device, white light is obtained by mixing blue light emitted from the blue LED chip and red light, green light, or the like emitted from the phosphor upon receiving the blue light.

In a general white LED device, an LED chip and its mounting part are covered with a wavelength conversion layer in which phosphor particles are dispersed in a transparent resin (for example, Patent Document 1). However, the transparent resin has high gas permeability. For this reason, when the white LED device is used in an environment containing sulfur gas or moisture, there is a problem that the metal wiring and the light reflecting surface of the LED element are deteriorated and the light extraction efficiency from the LED device is lowered.

For such problems, it has been proposed to form a barrier layer made of a curable resin material or the like between the LED element and the wavelength conversion layer (Patent Document 1). It has also been proposed to form a barrier layer made of a polymer such as tetraalkoxysilane or trialkoxyvinylsilane between the LED element and the wavelength conversion layer (Patent Document 2). Furthermore, a barrier layer in which the composition ratio in the layer of tetrafunctional alkoxysilane, trifunctional alkoxysilane, and bifunctional alkoxysilane is changed has also been proposed (Patent Document 3).

On the other hand, in order to suppress reflection at the interface between the LED chip and the wavelength conversion layer, a sealing material mainly composed of a polymer of a bifunctional and trifunctional silane compound is formed between the LED chip and the wavelength conversion layer. This has also been proposed (Patent Document 4).

JP 2011-096842 A JP 2012-1553827 A JP 2012-156384 A Japanese Patent Laid-Open No. 2007-112975

However, since the barrier layer of Patent Document 1 is made of resin, there is a problem that the gas barrier property is not sufficient. Further, since the barrier layers of Patent Document 2 and Patent Document 3 have a large amount of organic groups in the film, the barrier layer may be deteriorated with time by heat or light. Also, the sealing material of Patent Document 4 has a large amount of organic groups in the film. Therefore, there is a problem that the gas barrier property is low and the light extraction efficiency of the LED device is lowered with time.

The present invention has been made in view of the above-described problems. That is, an object of the present invention is to provide a sealant for an LED device that can form a dense film with little distortion, and an LED device using the same.

That is, the first aspect of the present invention relates to the following LED device sealant.
[1] An LED device encapsulant comprising a polysiloxane compound, a silane coupling agent, and metal oxide fine particles, the LED device encapsulant being held at 65 ° C. for 12 hours, and then at 150 ° C. The solid Si-nuclear magnetic resonance spectrum of the cured film which was cured by holding for 3 hours in the region has a peak top position in the region of chemical shift of −120 ppm to −90 ppm and a full width at half maximum of greater than 5.0 ppm to 12 ppm. And the peak top position is in the region of chemical shift of −80 ppm to −40 ppm and the half width is greater than 5.0 ppm and less than or equal to 12 ppm, and the silanol content of the cured film is The sealing agent for LED devices which is more than 10 mass% and 30 mass% or less.

[2] The sealant for an LED device according to [1], further including an organometallic compound containing a metal element other than Si.
[3] The encapsulant for LED device according to [1] or [2], wherein the refractive index of the cured product of the organometallic compound is 1.48 or more.

2nd of this invention is related with the following LED apparatuses.
[4] An LED element, a sealing layer that covers the LED element, and a wavelength conversion layer that is formed on the sealing layer and includes a transparent resin and phosphor particles, and the sealing layer is the aforementioned An LED device, which is a cured film of the sealant for an LED device according to any one of [1] to [3].

According to the sealant for an LED device of the present invention, a dense film with little distortion can be obtained. That is, it is possible to obtain a film that hardly causes cracks and has high gas barrier properties. Therefore, if the LED device sealing layer is formed using the LED device sealing agent, the high light extraction efficiency of the LED device can be maintained over a long period of time.

It is a schematic sectional drawing which shows an example of the LED apparatus of this invention. It is a schematic sectional drawing which shows the other example of the LED apparatus of this invention.

Hereinafter, the present invention will be described in detail, but the present invention is not limited to the following embodiments, and various modifications can be made within the scope of the gist.

1. LED Device Sealant The LED device sealant of the present invention (hereinafter sometimes simply referred to as “sealant”) is a composition for forming a sealing layer of an LED device described later.

The sealant of the present invention includes a polysiloxane compound, a silane coupling agent, and metal oxide fine particles. The sealant may contain an organometallic compound containing a metal element other than Si, a solvent, or the like as necessary.

As described above, the sealing layer in the conventional LED device contains many organic groups in the film. For this reason, there is a problem that the gas barrier property is not sufficient or deteriorates with time. On the other hand, if the amount of organic groups in the film is reduced, the film is likely to be distorted and cracks are likely to occur. Therefore, it is difficult to form a dense film with little distortion.

In contrast, the cured product of the sealant of the present invention has little distortion despite the small amount of organic groups. This is because the metal oxide fine particles are contained in the sealant of the present invention, so that stress generated when the sealant is cured is relieved by the metal oxide fine particles. Therefore, according to the sealing agent of this invention, a sealing layer with few cracks and high gas-barrier property is obtained.

1-1) Polysiloxane compound The polysiloxane compound contained in the sealant is obtained by polymerizing a tetrafunctional, trifunctional, or bifunctional silane compound. The polysiloxane compound is obtained, for example, by polymerizing alkoxysilane or aryloxysilane represented by the following general formula (I).
Si (OR) _n Y _4-n (I)

In general formula (I), n represents the number of alkoxy groups or aryloxy groups (OR) and is an integer of 2 or more and 4 or less. R each independently represents an alkyl group or a phenyl group, and preferably represents an alkyl group having 1 to 5 carbon atoms or a phenyl group.

In the general formula (I), Y represents a hydrogen atom or a monovalent organic group. Specific examples of the monovalent organic group represented by Y include an aliphatic group having 1 to 1000 carbon atoms, preferably 500 or less, more preferably 100 or less, still more preferably 50 or less, and particularly preferably 6 or less. An alicyclic group, an aromatic group, and an alicyclic aromatic group are included. These monovalent organic groups may be an aliphatic group, an alicyclic group, an aromatic group, or a group in which alicyclic aromatic groups are bonded to each other through a linking group. The linking group may be an atom such as O, N, or S, or an atomic group containing these. Moreover, the monovalent organic group represented by Y may have a substituent. Examples of the substituent include, for example, halogen atoms such as F, Cl, Br, and I; vinyl group, methacryloxy group, acryloxy group, styryl group, mercapto group, epoxy group, epoxycyclohexyl group, glycidoxy group, amino group, cyano group An organic functional group such as a group, a nitro group, a sulfonic acid group, a carboxy group, a hydroxy group, an acyl group, an alkoxy group, an imino group, and a phenyl group.

The alkoxysilane or aryloxysilane represented by the general formula (I) can be, for example, the following tetrafunctional silane compound, trifunctional silane compound, bifunctional silane compound, or the like.

Examples of tetrafunctional silane compounds include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, tetrapentyloxysilane, tetraphenyloxysilane, trimethoxymonoethoxysilane, dimethoxydiethoxysilane, triethoxymono Methoxysilane, trimethoxymonopropoxysilane, monomethoxytributoxysilane, monomethoxytripentyloxysilane, monomethoxytriphenyloxysilane, dimethoxydipropoxysilane, tripropoxymonomethoxysilane, trimethoxymonobutoxysilane, dimethoxydibutoxysilane , Triethoxymonopropoxysilane, diethoxydipropoxysilane, tributoxymonopropoxysilane, dimethoxymonoethoxymonobutoxy Silane, diethoxymonomethoxymonobutoxysilane, diethoxymonopropoxymonobutoxysilane, dipropoxymonomethoxymonoethoxysilane, dipropoxymonomethoxymonobutoxysilane, dipropoxymonoethoxymonobutoxysilane, dibutoxymonomethoxymonoethoxysilane, Examples include tetraalkoxysilanes such as dibutoxy monoethoxy monopropoxy silane and monomethoxy monoethoxy monopropoxy monobutoxy silane. Among these, tetramethoxysilane and tetraethoxysilane are preferable.

Examples of trifunctional silane compounds include trimethoxysilane, triethoxysilane, tripropoxysilane, tripentyloxysilane, triphenyloxysilane, dimethoxymonoethoxysilane, diethoxymonomethoxysilane, dipropoxymonomethoxysilane, di Propoxymonoethoxysilane, dipentyloxylmonomethoxysilane, dipentyloxymonoethoxysilane, dipentyloxymonopropoxysilane, diphenyloxylmonomethoxysilane, diphenyloxymonoethoxysilane, diphenyloxymonopropoxysilane, methoxyethoxypropoxysilane, monopropoxydimethoxysilane Monopropoxydiethoxysilane, monobutoxydimethoxysilane, monopentyloxydiethoxysilane, monophenyl Monohydrosilane compounds such as ruoxydiethoxysilane; methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, methyltripentyloxysilane, methylmonomethoxydiethoxysilane, methylmonomethoxydipropoxysilane, methylmonomethoxydipentyl Monomethylsilane compounds such as oxysilane, methylmonomethoxydiphenyloxysilane, methylmethoxyethoxypropoxysilane, methylmonomethoxymonoethoxymonobutoxysilane; ethyltrimethoxysilane, ethyltripropoxysilane, ethyltripentyloxysilane, ethyltriphenyloxy Silane, ethyl monomethoxydiethoxysilane, ethyl monomethoxydipropoxysilane, ethyl monomethoxydipentyloxy Monoethylsilane compounds such as lan, ethylmonomethoxydiphenyloxysilane, ethylmonomethoxymonoethoxymonobutoxysilane; propyltrimethoxysilane, propyltriethoxysilane, propyltripentyloxysilane, propyltriphenyloxysilane, propylmonomethoxydi Monopropylsilane compounds such as ethoxysilane, propylmonomethoxydipropoxysilane, propylmonomethoxydipentyloxysilane, propylmonomethoxydiphenyloxysilane, propylmethoxyethoxypropoxysilane, propylmonomethoxymonoethoxymonobutoxysilane; butyltrimethoxysilane, Butyltriethoxysilane, Butyltripropoxysilane, Butyltripentyloxysilane, Butyltriphenyl Monobutylsilane compounds such as oxysilane, butylmonomethoxydiethoxysilane, butylmonomethoxydipropoxysilane, butylmonomethoxydipentyloxysilane, butylmonomethoxydiphenyloxysilane, butylmethoxyethoxypropoxysilane, butylmonomethoxymonoethoxymonobutoxysilane Is included. Among these, methyltrimethoxysilane and methyltriethoxysilane are more preferable, and methyltrimethoxysilane is more preferable.

Specific examples of the bifunctional silane compound include dimethoxysilane, diethoxysilane, dipropoxysilane, dipentyloxysilane, diphenyloxysilane, methoxyethoxysilane, methoxypropoxysilane, methoxypentyloxysilane, methoxyphenyloxysilane, ethoxypropoxy. Silane, ethoxypentyloxysilane, ethoxyphenyloxysilane, methyldimethoxysilane, methylmethoxyethoxysilane, methyldiethoxysilane, methylmethoxypropoxysilane, methylmethoxypentyloxysilane, methylmethoxyphenyloxysilane, ethyldipropoxysilane, ethylmethoxy Propoxysilane, ethyldipentyloxysilane, ethyldiphenyloxysilane, propyldimethoxysilane, pro Rumethoxyethoxysilane, propylethoxypropoxysilane, propyldiethoxysilane, propyldipentyloxysilane, propyldiphenyloxysilane, butyldimethoxysilane, butylmethoxyethoxysilane, butyldiethoxysilane, butylethoxypropoxysilane, butyldipropoxysilane, Butylmethyldipentyloxysilane, butylmethyldiphenyloxysilane, dimethyldimethoxysilane, dimethylmethoxyethoxysilane, dimethyldiethoxysilane, dimethyldipentyloxysilane, dimethyldiphenyloxysilane, dimethylethoxypropoxysilane, dimethyldipropoxysilane, diethyldimethoxysilane, Diethylmethoxypropoxysilane, diethyldiethoxysilane, diethyl Toxipropoxysilane, dipropyldimethoxysilane, dipropyldiethoxysilane, dipropyldipentyloxysilane, dipropyldiphenyloxysilane, dibutyldimethoxysilane, dibutyldiethoxysilane, dibutyldipropoxysilane, dibutylmethoxypentyloxysilane, dibutylmethoxyphenyl Oxysilane, methylethyldimethoxysilane, methylethyldiethoxysilane, methylethyldipropoxysilane, methylethyldipentyloxysilane, methylethyldiphenyloxysilane, methylpropyldimethoxysilane, methylpropyldiethoxysilane, methylbutyldimethoxysilane, methylbutyl Diethoxysilane, methylbutyldipropoxysilane, methylethylethoxypropoxysilane, ethyl Includes rupropyldimethoxysilane, ethylpropylmethoxyethoxysilane, dipropyldimethoxysilane, dipropylmethoxyethoxysilane, propylbutyldimethoxysilane, propylbutyldiethoxysilane, dibutylmethoxyethoxysilane, dibutylmethoxypropoxysilane, dibutylethoxypropoxysilane, etc. It is. Of these, dimethoxysilane, diethoxysilane, methyldimethoxysilane, and methyldiethoxysilane are preferable.

The polysiloxane compound is prepared by hydrolyzing the above alkoxysilane or aryloxysilane in the presence of an acid catalyst, water, and an organic solvent, followed by a condensation reaction. The polysiloxane compound may be obtained by previously mixing a tetrafunctional silane compound, a trifunctional silane compound, or a bifunctional silane compound at a desired molar ratio, and randomly polymerizing the compound. Alternatively, a block copolymer may be prepared by polymerizing a trifunctional silane compound or a bifunctional silane compound alone to some extent to form an oligomer, and then polymerizing only the tetrafunctional silane compound to the oligomer.

The ratio of the amount of the tetrafunctional silane compound to the total amount of the bifunctional silane compound, the trifunctional silane compound, and the tetrafunctional silane compound of the polysiloxane compound contained in the sealing agent is preferably 20% by mass or more, and more preferably. Is 25 to 70% by mass, more preferably 30 to 60% by mass. When the ratio of the tetrafunctional silane compound is 20% by mass or more, a film having a high gas barrier property is easily obtained.

The polysiloxane compound is more preferably a polymer obtained by polymerizing a tetrafunctional silane compound and a trifunctional silane compound, and particularly preferably a polymer obtained by polymerizing a tetrafunctional silane compound and a trifunctional monomethylsilane compound. The polymerization ratio between the tetrafunctional silane compound and the trifunctional silane compound is not limited, but the polymerization molar ratio is preferably 3: 7 to 7: 3, and more preferably 4: 6 to 6: 4.

The mass average molecular weight of the polysiloxane compound is preferably 1000 to 3000, more preferably 1200 to 2700, and further preferably 1500 to 2000. When the mass average molecular weight of the polysiloxane compound is in the above range, the viscosity of the sealant tends to fall within a desired range. The mass average molecular weight of the polysiloxane compound is a value (polystyrene conversion) measured by gel permeation chromatography. The mass average molecular weight of the polysiloxane compound is adjusted by reaction conditions (particularly reaction time) at the time of preparing the polysiloxane compound.

The polysiloxane compound is preferably contained in the sealing agent in an amount of 0.1 to 50% by mass. Further, it is preferably contained in the solid content of the sealant (all components excluding the solvent) in an amount of 50 to 90% by mass, more preferably 60 to 80% by mass. When the amount of the polysiloxane compound is within the above range, the gas barrier property of the sealing layer obtained by curing the sealing agent is increased.

1-2) Silane coupling agent When the sealing agent contains a silane coupling agent, the sealing layer obtained by curing the sealing agent and the LED element (especially a wiring or a reflective layer made of a metal) are in close contact with each other. Increases nature. The kind of silane coupling agent is not particularly limited, and may be a known silane coupling agent.

Silane coupling agents include vinyl group-containing silane coupling agents such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, vinyltris (2-methoxyethoxy) silane, and vinyltrichlorosilane; γ-glycidoxypropyltri Methoxysilane, γ-glycidoxypropyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ- (3,4 Epoxycyclohexyl) Epoxy group-containing silane coupling agents such as ethyltriethoxysilane; 3-methacryloxypropyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, and the like Silyl group-containing silane coupling agents; mercapto group-containing silane coupling agents such as 3-mercaptopropyltrimethoxysilane and 3-mercaptopropylmethyldimethoxysilane; 4-aminobutyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3 -Aminopropyltriethoxysilane, p-aminophenyltrimethoxysilane, aminoethylaminomethylphenethyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (6-aminohexyl) amino Amino group-containing silane coupling agents such as propyltrimethoxysilane; styryl group-containing silane coupling agents such as styrylethyltrimethoxysilane; cyano group-containing silane coupling agents such as β-cyanoethyltriethoxysilane Methyldimethoxysilane, dimethyldiethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, methyltributoxysilane, trimethylethoxysilane, trimethylmethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, diphenyl Dimethoxysilane, diphenyldiethoxysilane, phenyltrimethoxysilane, methylphenyldimethoxysilane, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, (p-chloromethyl) phenyltrimethoxysilane, 4-chlorophenyltrimethoxy Silane Trimethylchlorosilane, Methyltrichlorosilane, 3-Chloropropyltrimethoxysilane, 3-Chloropropyltrimethyl Roshiran, dimethyldichlorosilane, trifluoropropyl trimethoxy silane, diphenyl dichlorosilane, and phenyl triacetoxy silane, can be a compound which they are partially condensed.

The silane coupling agent is preferably contained in the solid content of the sealing agent in an amount of 0.01 to 10% by mass, preferably 0.1 to 5.0% by mass. When the silane coupling agent is contained in an amount of 0.01% by mass or more, the adhesion between the sealing layer and the LED element is likely to increase.

1-3) Metal oxide fine particles The sealant contains metal oxide fine particles. As described above, when the metal oxide fine particles are contained in the sealant, the stress generated when the polysiloxane compound is polymerized is easily relieved, and the sealing layer obtained by curing the sealant has cracks. It becomes difficult to occur.

The type of metal oxide fine particles is not particularly limited, but the refractive index of the metal oxide fine particles is preferably higher than the refractive index of the polysiloxane compound. When metal oxide fine particles having a high refractive index are contained, the refractive index of the sealing layer obtained by curing the sealing agent is increased. In general, the refractive index of an LED element (LED chip) is considerably higher than that of a polysiloxane compound. Therefore, when the refractive index of the sealing layer is increased by the metal oxide fine particles; the refractive index difference between the LED element and the sealing layer is reduced, and the reflection of light at the interface between the LED element and the sealing layer is reduced. That is, the light extraction efficiency of the LED device is increased.

Specifically, the refractive index of the metal oxide fine particles is preferably 1.8 or more, and more preferably 2.0 or more. The refractive index of the metal oxide fine particles is measured by the Becke line method.

The average primary particle size of the metal oxide fine particles is preferably 1 to 100 nm, more preferably 1 to 80 nm, and still more preferably 1 to 50 nm. When the average primary particle size of the metal oxide fine particles is within such a range, the above-described crack suppressing effect and refractive index improving effect are easily obtained. The average primary particle size of the metal oxide fine particles is measured by a Coulter counter method.

Examples of the metal oxide fine particles include zirconium oxide, titanium oxide, tin oxide, cerium oxide, niobium oxide, and zinc oxide. Among these, since the refractive index is high, the metal oxide fine particles are preferably zirconium oxide fine particles. The sealant may contain only one kind of metal oxide fine particles or two or more kinds.

The metal oxide fine particles may have a surface treated with a silane coupling agent or a titanium coupling agent. The surface-treated metal oxide fine particles are easily dispersed uniformly in the sealant.

The metal oxide fine particles are preferably contained in the solid content of the sealant in an amount of 10 to 60% by mass, more preferably 15 to 45% by mass, and still more preferably 20 to 30% by mass. When the amount of the metal oxide fine particles is 10% by mass or more, the above-described crack suppressing effect is sufficiently obtained, and the refractive index improving effect is also sufficiently obtained. On the other hand, if it is 60 mass% or less of metal oxide microparticles | fine-particles, since the polysiloxane compound (binder) is fully contained, the intensity | strength and gas barrier property of a sealing layer will increase.

1-4) Organometallic compound containing a metal element other than Si The sealant may contain an organometallic compound containing a metal element other than Si. The organometallic compound can be a metal alkoxide or metal chelate of a divalent or higher metal element other than Si. The metal alkoxide or metal chelate forms a metalloxane bond with a polysiloxane compound, a LED chip, or a hydroxyl group present on the surface of the wavelength conversion layer. The metalloxane bond is very strong. Therefore, when a metal alkoxide or a metal chelate is contained in the sealant, the adhesion between the sealing layer obtained by curing the metal alkoxide or the metal chelate and the LED chip and the adhesion between the sealing layer and the wavelength conversion layer are enhanced.

On the other hand, a part of the metal alkoxide or metal chelate forms a nano-sized cluster composed of a metalloxane bond in the sealing layer obtained by curing the sealing agent. This cluster functions as a photocatalyst for converting hydrogen sulfide gas having high metal corrosivity into sulfur dioxide gas having low corrosivity. Therefore, when a metal alkoxide or a metal chelate is contained in the sealant, the resistance to sulfide gas of the LED device is also increased.

The refractive index of the cured product of the organometallic compound is preferably 1.48 or more, more preferably 1.50 to 1.90, still more preferably 1.55 to 1.80. When the refractive index of the organometallic compound is 1.48 or more, the refractive index of the sealing layer obtained by curing the sealing agent tends to increase. The refractive index is measured on a film cured by holding the organometallic compound at 65 ° C. for 12 hours and then holding at 150 ° C. for 3 hours. The refractive index of the cured product of the organometallic compound is measured by the Becke line method or the like.

The metal element contained in the metal alkoxide or metal chelate is preferably a group 4 or group 13 metal element other than the Si element, and a compound represented by the following general formula (III) is preferable.
M ^{m +} X _n Y _mn (III)
In general formula (III), M represents a Group 4 or Group 13 metal element, and m represents the valence (3 or 4) of M. X represents a hydrolyzable group, and n represents the number of X groups (an integer of 2 or more and 4 or less). However, m ≧ n. Y represents a monovalent organic group.

In the general formula (III), the group 4 or group 13 metal element represented by M is preferably aluminum, zirconium, or titanium, and more preferably zirconium. The cured product of zirconium alkoxide or chelate does not have an absorption wavelength in the emission wavelength region of the general LED chip 3 (particularly blue light (wavelength 420 to 485 nm)). That is, the light emitted from the LED chip is hardly absorbed by the cured product of zirconium alkoxide or chelate.

In the general formula (III), the hydrolyzable group represented by X may be a group that is hydrolyzed with water to form a hydroxyl group. Preferable examples of the hydrolyzable group include a lower alkoxy group having 1 to 5 carbon atoms, an acetoxy group, a butanoxime group, a chloro group and the like. In general formula (III), all the groups represented by X may be the same group or different groups.

The hydrolyzable group represented by X is hydrolyzed and released. Therefore, a group that is neutral and light-boiling is preferable after the hydrolysis. Therefore, the group represented by X is preferably a lower alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group or an ethoxy group.

In the general formula (III), the monovalent organic group represented by Y can be a monovalent organic group contained in a general silane coupling agent. Specifically, the aliphatic group, alicyclic group, aromatic group, fatty acid having 1 to 1000 carbon atoms, preferably 500 or less, more preferably 100 or less, further preferably 40 or less, and particularly preferably 6 or less. It may be a ring aromatic group. The organic group represented by Y may be an aliphatic group, an alicyclic group, an aromatic group, or a group in which an alicyclic aromatic group is bonded via a linking group. The linking group may be an atom such as O, N, or S, or an atomic group containing these.

The organic group represented by Y may have a substituent. Examples of the substituent include halogen atoms such as F, Cl, Br, and I; vinyl group, methacryloxy group, acryloxy group, styryl group, mercapto group, epoxy group, epoxycyclohexyl group, glycidoxy group, amino group, cyano group, Organic groups such as nitro group, sulfonic acid group, carboxy group, hydroxy group, acyl group, alkoxy group, imino group and phenyl group are included.

Specific examples of the metal alkoxide or metal chelate of aluminum represented by the general formula (III) include aluminum triisopropoxide, aluminum tri-n-butoxide, aluminum tri-t-butoxide, aluminum triethoxide and the like.

Specific examples of the metal alkoxide or metal chelate of zirconium represented by the general formula (III) include zirconium tetramethoxide, zirconium tetraethoxide, zirconium tetra n-propoxide, zirconium tetra i-propoxide, zirconium tetra n- Examples include butoxide, zirconium tetra-i-butoxide, zirconium tetra-t-butoxide, zirconium dimethacrylate dibutoxide, dibutoxyzirconium bis (ethylacetoacetate) and the like.

Specific examples of the metal alkoxide or metal chelate of the titanium element represented by the general formula (III) include titanium tetraisopropoxide, titanium tetra n-butoxide, titanium tetra i-butoxide, titanium methacrylate triisopropoxide, titanium tetra Examples include methoxypropoxide, titanium tetra n-propoxide, titanium tetraethoxide, titanium lactate, titanium bis (ethylhexoxy) bis (2-ethyl-3-hydroxyhexoxide), titanium acetylacetonate and the like.

However, the metal alkoxides or metal chelates exemplified above are a part of commercially available organometallic alkoxides or metal chelates. Metal alkoxides or metal chelates shown in the list of coupling agents and related products in Chapter 9 “Optimum Utilization Technology of Coupling Agents” published by the National Institute of Science and Technology are also applicable to the present invention.

The amount of the metal alkoxide or metal chelate (organometallic compound) contained in the sealing agent is preferably 5 to 100 parts by mass, more preferably 8 to 40 parts by mass with respect to 100 parts by mass of the polysiloxane compound. More preferably, it is 10 to 15 parts by mass. When the amount of the metal alkoxide or metal chelate is 5 parts by mass or more, the above-described adhesion improving effect is easily obtained. Moreover, if the quantity of a metal alkoxide or a metal chelate is 100 mass parts or less, the preservability of a sealing agent is favorable.

1-5) Solvent The sealing agent contains a solvent as necessary. Any solvent may be used as long as it can dissolve or uniformly disperse the above-described polysiloxane compound and silane coupling agent. Examples of the solvent include monohydric alcohols such as methanol, ethanol, propanol and n-butanol; alkyl carboxylic acid esters such as methyl-3-methoxypropionate and ethyl-3-ethoxypropionate; ethylene glycol, diethylene glycol, Polyhydric alcohols such as propylene glycol, glycerin, trimethylolpropane, hexanetriol; ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono Propyl ether, diethylene glycol monobutyl ether, propylene glycol mono Monoethers of polyhydric alcohols such as chill ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, or monoacets thereof; ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dipropyl ether, Polyhydric alcohol ethers in which all hydroxyl groups of polyhydric alcohols such as ethylene glycol dibutyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and diethylene glycol methyl ethyl ether are all alkyl etherified; methyl acetate, ethyl acetate, Such as butyl acetate Ethers; include like; acetone, acetylacetone, ketones such as methyl ethyl ketone and methyl isoamyl ketone. In the sealing agent, only one type of solvent may be contained, or two or more types may be contained.

The solvent preferably contains water. The amount of water is preferably 0.1 to 20% by mass, more preferably 0.1 to 10% by mass, based on the total mass of the sealant. If the amount of water contained in the sealant is too small, the polysiloxane compound may not be sufficiently hydrolyzed when forming the sealing layer of the LED device. On the other hand, when the amount of water contained in the sealant is excessive, the polysiloxane compound is hydrolyzed during storage of the sealant, and the sealant may be gelled.

The solvent preferably contains an organic solvent having a boiling point of 150 ° C. or higher (for example, ethylene glycol, propylene glycol, etc.). When an organic solvent having a boiling point of 150 ° C. or higher is contained, the storage stability of the sealant is increased. In addition, the solvent is less likely to volatilize in the coating apparatus, and the sealing agent can be applied stably. On the other hand, the boiling point of the solvent contained in the sealant is preferably 250 ° C. or lower. When the boiling point of the solvent exceeds 250 ° C., the drying property of the sealant decreases.

1-6) Physical properties of cured film of sealant After holding a sealant containing the above polysiloxane compound, silane coupling agent, metal oxide fine particles, organometallic compound, solvent, etc. at 65 ° C. for 12 hours, The cured film cured by holding at 150 ° C. for 3 hours has the following characteristics.
(I) The solid Si-nuclear magnetic resonance spectrum has a peak whose peak top position is in the region of chemical shift of −120 ppm to −90 ppm and the half width is greater than 5.0 ppm and not more than 12 ppm. (Ii) Solid The Si-nuclear magnetic resonance spectrum has a peak where the peak top position is in the region of chemical shift of −80 ppm to −40 ppm and the half width is greater than 5.0 ppm and not more than 12 ppm. (Iii) Silanol content is 10 More than 30% by mass and less than 30% by mass

The silicon atom that forms the cured film of the sealant usually has four oxygen atoms bonded; three oxygen atoms and one non-oxygen atom (carbon atom, etc.) bonded; two oxygen atoms and oxygen There are two bonded atoms.

A silicon atom to which four oxygen atoms are bonded is called a Q site. Peaks derived from the Q site (Q ⁿ peak group), solid Si- nucleus has a peak top in the region of the chemical shift -120 ~ -90 ppm magnetic resonance spectrum, it is observed as a peak of a continuous multimodal .

A silicon atom to which three oxygen atoms and one atom other than oxygen are bonded is called a T site. Peaks derived from the T site (T ⁿ peak group), solid Si- nucleus has a peak top in the region of chemical shift -80 ~ -40 ppm magnetic resonance spectrum, is observed as a peak of a continuous multimodal .

A silicon atom to which two oxygen atoms and two atoms other than oxygen are bonded is called a D site. Peaks derived from the D site (D ⁿ peak group), solid Si- nucleus has a peak top in the region of chemical shift -40 ~ 0 ppm magnetic resonance spectrum, is observed as a peak of a continuous multimodal.

The smaller the half width of the Q ⁿ peak group and the T ⁿ peak group detected in the solid Si-nuclear magnetic resonance spectrum, the narrower the distribution of bond angles of siloxane bonds (Si—O—Si). That is, it can be said that there is little distortion of a cured film and there is little internal stress. As described above, the cured film of the sealant of the present invention, (i) the half-width of the ^{Q n} peak group is not more than greater than 5.0 ppm 12 ppm, preferably 5.5 ~ 12 ppm, more preferably 6.0 to 11 ppm. Further, (ii) ^{T n} FWHM of peaks is less than or equal to greater than 5.0 ppm 12 ppm, preferably 5.5 ~ 12 ppm, more preferably from 6.0 ~ 11 ppm. That is, the cured film of the encapsulant has a relatively small half-value width of the Q ⁿ peak group and the T ⁿ peak group, and a low internal stress.

Here, the ratio of the area of the Q ⁿ peak group to the total area of the Q ⁿ peak group, the T ⁿ peak group, and the D ⁿ peak group is preferably 10% to 70%, and preferably 30% to 60%. Is more preferable. The area ratio of each peak group is proportional to the composition ratio of each site. Then, the area of the Q ⁿ peak group becomes excessive; the words Q site is excessive, the crosslinking density increases, spread distribution of bond angle, half-width tends to spread. The amounts of Q site, T site, and D site are adjusted by the polymerization ratio of the tetrafunctional silane compound, the trifunctional silane compound, and the bifunctional silane compound during polymerization of the polysiloxane compound.

On the other hand, the (iii) silanol content of the cured film of the sealant is more than 10% by mass and 30% by mass or less, preferably 11 to 29% by mass, and more preferably 11 to 28% by mass. When a certain amount of silanol remains in the cured film of the sealing agent, the adhesion between the sealing layer obtained by curing the sealing agent and the other layers tends to increase. However, if the amount of remaining silanol is too large, the silanols may be dehydrated and condensed over time, and the film may be distorted over time.

The silanol content is also adjusted by the ratio of Q site, T site, and D site contained in the cured film. When the ratio of T sites or D sites increases, the silanol content tends to decrease. On the other hand, when the ratio of the Q site increases, the silanol content tends to increase.

The half width and silanol content are calculated by measuring the cured film of the sealant with a solid Si-NMR apparatus. The silanol content is calculated from the ratio of the silanol-derived peak area (usually manifested in a chemical shift of −50 to 150 ppm) to the total peak area of the spectrum measured with a solid-state Si-NMR apparatus.

2. LED device The above-mentioned sealing agent has the LED element 10, the sealing layer 5, and the wavelength conversion layer 6 formed on the sealing layer 5 which are shown by the schematic sectional drawing of FIG.1 and FIG.2, for example. It is used for forming the sealing layer 5 of the LED device 100.

2-1) LED element The LED element 10 may include a package 1, an LED chip 2, a metal reflective layer 3, and the like.

Package 1 may be, for example, a liquid crystal polymer or ceramic, but the material is not particularly limited as long as it has insulating properties and heat resistance. The shape is not particularly limited, and may be concave as shown in FIG. 1, for example, or may be flat as shown in FIG.

The emission wavelength of the LED chip 2 is not particularly limited. The LED chip 2 may emit blue light (light of about 420 nm to 485 nm), or may emit ultraviolet light, for example.

The configuration of the LED chip 2 is not particularly limited. When the emission color of the LED chip 2 is blue, the LED chip 2 includes an n-GaN compound semiconductor layer (cladding layer), an InGaN compound semiconductor layer (light emitting layer), and a p-GaN compound semiconductor layer (cladding layer). Layer) and a transparent electrode layer. The LED chip 2 may have a light emitting surface of 200 to 300 μm × 200 to 300 μm, for example. The height of the LED chip 2 is usually about 50 to 200 μm.

The metal reflection layer 3 is made of a metal such as silver, and reflects light emitted from the LED chip 2 toward the light extraction surface. The metal reflection layer 3 may also serve as a metal wiring that supplies current to the LED chip 2.

As shown in FIG. 1, the LED chip 2 may be electrically connected to the metal electrode (metal reflective layer) 3 via a wire 4, and as shown in FIG. 2, the LED chip 2 is a protruding electrode. The metal electrode (metal reflective layer 3) may be electrically connected via 7. A mode in which the LED chip 2 is connected to the metal electrode 3 through the wire 4 is referred to as a wire bonding type, and a mode in which the LED chip 2 is connected to the metal electrode (metal reflective layer) 3 through the protruding electrode 7 is referred to as a flip chip type.

In the LED device 100 shown in FIGS. 1 and 2, only one LED chip 2 is disposed in the package 1; however, a plurality of LED chips 2 may be disposed in the package 1.

2-2) Sealing layer The sealing layer 5 is made of a cured film of the above-described sealing agent. The sealing layer 5 serves to protect the LED chip 2 and the metal reflective layer 3 of the LED element 10 from hydrogen sulfide gas or the like.

The thickness of the sealing layer 5 is preferably 0.3 to 10 μm, more preferably 0.5 to 5 μm, still more preferably 0.7 to 2 μm. If the thickness of the sealing layer 5 is less than 0.3 μm, sufficient gas barrier properties may not be obtained. On the other hand, when the thickness of the sealing layer 5 exceeds 10 μm, cracks are likely to occur in the sealing layer 5, and the strength of the sealing layer 5 tends to decrease. The thickness of the sealing layer 5 means the maximum thickness of the sealing layer 5 disposed on the LED chip 2 described above. The layer thickness is measured using a laser holo gauge.

2-3) Wavelength Conversion Layer The wavelength conversion layer 6 is a layer that converts light of a specific wavelength emitted from the LED chip 2 into light of another specific wavelength. The wavelength conversion layer 6 is a layer in which phosphor particles are dispersed in a transparent resin.

The phosphor particles are excited by the wavelength of light emitted from the LED chip 2 (excitation wavelength), and emit fluorescent light having a wavelength different from the excitation wavelength. For example, when blue light is emitted from the LED chip 2, a white LED device can be obtained by adding phosphor particles that emit yellow fluorescence to the wavelength conversion layer 6. Examples of the phosphor particles that emit yellow fluorescence include YAG (yttrium, aluminum, garnet) phosphors. The YAG phosphor emits yellow (wavelength 550 nm to 650 nm) fluorescence using blue light (wavelength 420 nm to 485 nm) emitted from the blue LED element as excitation light.

The phosphor particles are, for example, 1) an appropriate amount of a fluoride such as ammonium fluoride is mixed and pressed into a mixed raw material having a predetermined composition to obtain a molded body, and 2) the obtained molded body is put into a crucible. It is manufactured by packing and firing in air at a temperature range of 1350 to 1450 ° C. for 2 to 5 hours to obtain a sintered body.

A mixed raw material having a predetermined composition can be obtained by sufficiently mixing oxides of Y, Gd, Ce, Sm, Al, La, Ga, or compounds that easily become oxides at high temperatures in a stoichiometric ratio. it can. Alternatively, the mixed raw material having a predetermined composition includes a coprecipitation oxide obtained by coprecipitation with oxalic acid in a solution in which a rare earth element of Y, Gd, Ce, and Sm is dissolved in acid at a stoichiometric ratio, and aluminum oxide It can be obtained by mixing with gallium oxide.

The kind of the phosphor particles is not limited to the YAG phosphor, and may be other phosphor particles such as a non-garnet phosphor not containing Ce.

The average primary particle diameter of the phosphor particles is preferably 1 μm or more and 50 μm or less, and more preferably 10 μm or less. The larger the particle size of the phosphor particles, the higher the light emission efficiency (wavelength conversion efficiency). On the other hand, if the particle size of the phosphor particles is too large, the adhesion between the phosphor particles and the transparent resin is lowered, and the strength of the wavelength conversion layer is lowered. The average primary particle diameter of the phosphor particles is measured by, for example, a Coulter counter method.

The amount of phosphor particles contained in the wavelength conversion layer 6 is preferably 5 to 15% by mass, more preferably 9 to 11% by mass, based on the total amount of the wavelength conversion layer.

The transparent resin contained in the wavelength conversion layer 6 is not particularly limited as long as it is a thermosetting resin transparent to visible light. Examples of transparent resins include epoxy-modified silicone resins, alkyd-modified silicone resins, acrylic-modified silicone resins, polyester-modified silicone resins, phenyl silicone resins and other silicone resins; epoxy resins; acrylic resins; methacrylic resins; transparent resins such as urethane resins Etc. are included. A phenyl silicone resin is particularly preferable. When the transparent resin is a phenyl silicone resin, the moisture resistance of the LED device 100 is increased.

The thickness of the wavelength conversion layer 6 is usually preferably 25 μm to 5 mm, more preferably 0.5 to 3 mm. If the wavelength conversion layer is too thick, the phosphor particle concentration in the wavelength conversion layer becomes excessively low, and the phosphor particles may not be uniformly dispersed.

3. Manufacturing method of LED device The manufacturing method of the LED device of this invention includes the following three processes.
1) A step of preparing an LED element including an LED chip and a metal reflective layer 2) A step of applying the above-mentioned sealing agent so as to cover the LED chip and the metal reflective layer, and forming a sealing layer 3) The sealing A step of forming a wavelength conversion layer containing phosphor particles and a transparent resin on the stop layer

3-1) LED element preparation step In the LED element preparation step, an LED element is prepared. For example, it may be a step of electrically connecting a metal reflective layer formed on a package and an LED chip and fixing the LED chip to the package. The method for connecting the metal reflecting portion and the LED chip and the method for fixing the LED chip to the package are not particularly limited, and may be the same as a conventionally known method.

3-2) Sealing layer forming step The sealing agent described above is applied so as to cover the LED chip and the metal reflective layer of the LED element. Covering the LED chip and the metal reflective layer refers to covering at least the light emitting surface of the LED chip and the metal reflective layer. For example, as shown in FIG. It does not have to be coated.

The means for applying the sealant is not particularly limited. For example, a conventionally known method such as a bar coating method, a spin coating method, a spray coating method, a dispensing method, a jet dispensing method, or the like can be used. In particular, according to the spray coating method, a thin sealing layer can be formed.

After applying the sealing agent, the polysiloxane compound is dried and cured by heating the coating film to 100 ° C. or higher, preferably 150 to 300 ° C. If the heating temperature is less than 100 ° C., water generated during dehydration condensation of the polysiloxane compound cannot be sufficiently removed, and the gas barrier property of the sealing layer may be lowered.

3-3) Wavelength conversion layer forming step A wavelength conversion layer is formed on the aforementioned sealing layer. The wavelength conversion layer is obtained by preparing a composition for forming a wavelength conversion layer containing a transparent resin or a precursor thereof and phosphor particles, and applying and curing the composition on the light transmitting layer.

The wavelength conversion layer forming composition includes a transparent resin or a precursor thereof and phosphor particles. A solvent, various additives, etc. may be contained as needed. The solvent is not particularly limited as long as it can dissolve the transparent resin or its precursor. The solvent can be, for example, hydrocarbons such as toluene and xylene; ketones such as acetone and methyl ethyl ketone; ethers such as diethyl ether and tetrahydrofuran; esters such as propylene glycol monomethyl ether acetate and ethyl acetate;

The mixing of the composition for forming a wavelength conversion layer can be performed, for example, with a stirring mill, a blade kneading stirring device, a thin film swirl type dispersing machine, or the like. By adjusting the stirring conditions, it is possible to suppress the precipitation of the phosphor particles in the wavelength conversion layer forming composition.

The method for applying the wavelength conversion layer forming composition is not particularly limited. For example, the wavelength conversion layer forming composition can be applied by a general application apparatus such as the aforementioned dispenser. Moreover, the curing method and curing conditions of the wavelength conversion layer forming composition are appropriately selected depending on the type of the transparent resin. An example of the curing method is heat curing.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the scope of the present invention is not limited by this.

<Preparation of phosphor particles>
The method for preparing phosphor particles used in Examples and Comparative Examples is shown.
As the phosphor material, 7.41 g of Y ₂ O ₃ , 4.01 g of Gd ₂ O ₃ , 0.63 g of CeO ₂ , and 7.77 g of Al ₂ O ₃ were sufficiently mixed. An appropriate amount of ammonium fluoride was mixed as a flux to this and filled in an aluminum crucible. The packing is fired at a temperature range of 1350 to 1450 ° C. for 2 to 5 hours in a reducing atmosphere in which hydrogen-containing nitrogen gas is circulated to obtain a fired product ((Y _0.72 Gd _0.24 ) ₃ Al ₅ O ₁₂ : Ce _0.04 ).

The obtained fired product was pulverized, washed, separated, and dried to obtain yellow phosphor particles having an average particle diameter of about 10 μm. When the emission wavelength of excitation light with a wavelength of 465 nm was measured, it had a peak wavelength at a wavelength of approximately 570 nm.

[Example 1]
29.5 g of methyltrimethoxysilane, 32.8 g of tetramethoxysilane, 40.0 g of methanol, and 40.0 g of acetone were mixed and stirred. To this mixed solution, 54.6 g of water and 47 μL of an aqueous nitric acid solution having a concentration of 60% by mass were added. This mixed solution was further stirred for 3 hours to obtain a polysiloxane-containing solution containing a polysiloxane compound of trifunctional component: tetrafunctional component (polymerization molar ratio) = 4: 6.

A polysiloxane compound-containing solution, 1 part by mass of a silane coupling agent (3-glycidoxypropyltrimethoxysilane), and 10 parts by mass of a slurry in which ZrO ₂ fine particles are dispersed (TECNADIS-ZR-220: manufactured by TECNAN) It mixed and the sealing agent for LED devices was prepared. The polysiloxane compound-containing solution was added so that the amount of the polysiloxane compound was 89 parts by mass.

An aromatic polyamide circular package (substrate) (opening diameter 3 mm, bottom diameter 2 mm, opening wall inclination angle 60 °) was prepared. Wiring made of silver plating is formed on the bottom surface of the package. One blue LED chip (cuboid shape: 200 μm × 300 μm × 100 μm) was fixed to the center of the opening of the circular package with a die-bonding adhesive. Furthermore, the anode electrode and the cathode electrode of the LED chip were each connected to the electrode with a wire (gold wire) to obtain an LED element.

The aforementioned sealing agent for LED device was applied with a spray device so as to cover the LED chip and the wiring of the LED element, and dried at 150 ° C. for 1 hour to form a sealing layer. The thickness of the sealing layer was 0.9 μm.

Subsequently, 9 g of methyl silicone (manufactured by Shin-Etsu Chemical Co., Ltd .: KER-2500) and the above phosphor particles were mixed and degassed to obtain a wavelength conversion layer composition. The wavelength conversion layer composition was applied onto the sealing layer with a dispenser and heated at 150 ° C. for 1 hour to form a wavelength conversion layer; the LED element, the sealing layer, and the wavelength conversion layer were laminated. An LED device was obtained. The thickness of the wavelength conversion layer was 1000 μm.

[Example 2]
An LED device encapsulant was prepared in the same manner as in Example 1 except that the silane coupling agent was changed to 3-methacryloxypropyltrimethoxysilane to produce an LED device.

[Example 3]
An LED device sealant was prepared in the same manner as in Example 1 except that the silane coupling agent was changed to 3-aminopropyltriethoxysilane, and an LED device was produced.

[Example 4]
An LED device encapsulant was prepared in the same manner as in Example 1 except that the silane coupling agent was changed to 3-mercaptopropylmethyldimethoxysilane to produce an LED device.

[Example 5]
Trifunctional component: tetrafunctional component (polymerization molar ratio) = 6: 4 as in Example 1, except that the amount of methyltrimethoxysilane was 35.4 g and the amount of tetramethoxysilane added was 26.2 g. A polysiloxane-containing solution containing a polysiloxane compound was obtained.

A solution containing a polysiloxane compound, 10 parts by mass of a silane coupling agent (X-41-1810: manufactured by Shin-Etsu Chemical Co., Ltd.), 10 parts by mass of a slurry in which TiO ₂ fine particles are dispersed (TECNADIS-TI-220: manufactured by TECNAN) Were mixed to prepare an LED device sealant. The polysiloxane compound-containing solution was added so that the amount of the polysiloxane compound was 80 parts by mass.

The aforementioned sealing agent for LED device was applied with a spray device so as to cover the LED chip and the wiring of the LED element, and dried at 150 ° C. for 1 hour to form a sealing layer. Then, the composition for wavelength conversion layers was formed similarly to Example 1, and the LED device was obtained.

[Example 6]
In the same manner as in Example 5, a polysiloxane compound-containing solution was prepared. 10 parts by mass of the polysiloxane-containing solution, 30 parts by mass of a silane coupling agent (X-41-1053: manufactured by Shin-Etsu Chemical Co., Ltd.), and a slurry in which Al ₂ O ₃ fine particles are dispersed (TECNADIS-AL-220: manufactured by TECNAN) Part and 10 parts by mass of zirconium dimethacrylate dibutoxide were mixed to prepare an LED device sealant. The polysiloxane compound-containing solution was added so that the amount of the polysiloxane compound was 50 parts by mass.

The aforementioned sealing agent for LED device was applied with a spray device so as to cover the LED chip and the wiring of the LED element, and dried at 150 ° C. for 1 hour to form a sealing layer. Then, the composition for wavelength conversion layers was formed similarly to Example 1, and the LED device was obtained. The refractive index of the cured product of zirconium dimethacrylate dibutoxide was 1.64. The refractive index of the cured product of zirconium dimethacrylate dibutoxide was measured as follows. Zirconium dimethacrylate dibutoxide was cured at 65 ° C. for 12 hours and then at 150 ° C. for 3 hours. The cured product was finely crushed, placed in a refractive index standard solution, and placed on a slide glass. Then, a cover glass was placed, a line (Becke line) shining around the sample fragments was observed with a microscope with a narrowed aperture, and the refractive index was measured.

[Example 7]
Bifunctional component: trifunctional as in Example 1, except that the amount of dimethyldimethoxysilane was 5.2 g, the amount of methyltrimethoxysilane was 17.6 g, and the amount of tetramethoxysilane was 39.4 g. Component: A polysiloxane-containing solution containing a polysiloxane compound of 4 functional components (polymerization molar ratio) = 1: 3: 6 was obtained.

The polysiloxane-containing solution, 5 parts by mass of a silane coupling agent (3-chloropropyltrichlorosilane), 20 parts by mass of a slurry in which TiO ₂ fine particles are dispersed (TECNADIS-TI-220: manufactured by TECNAN), titanium tetran -5 parts by mass of butoxide was mixed to prepare an LED device sealant. The polysiloxane compound-containing solution was added so that the amount of the polysiloxane compound was 50 parts by mass.

The aforementioned sealing agent for LED device was applied with a spray device so as to cover the LED chip and the wiring of the LED element, and dried at 150 ° C. for 1 hour to form a sealing layer. Then, the composition for wavelength conversion layers was formed similarly to Example 1, and the LED device was obtained. The refractive index of the cured product of titanium tetra n-butoxide was 1.70. The refractive index of the cured product of titanium tetra n-butoxide was measured as follows. Titanium tetra n-butoxide was cured at 65 ° C. for 12 hours and then at 150 ° C. for 3 hours. The cured product was finely crushed, placed in a refractive index standard solution, and placed on a slide glass. Then, a cover glass was placed, a line (Becke line) shining around the sample fragments was observed with a microscope with a narrowed aperture, and the refractive index was measured.

[Comparative Example 1]
An LED device was obtained in the same manner as in Example 1 except that the sealing layer was not formed.

[Comparative Example 2]
Polysiloxane compound of trifunctional component: tetrafunctional component (polymerization molar ratio) = 9: 1 as in Example 1, except that the amount of methyltrimethoxysilane was 44.1 g and the amount of tetramethoxysilane was 5.5 g A polysiloxane-containing solution containing was obtained. An LED device was obtained in the same manner as in Example 1 except that the polysiloxane-containing solution was applied by a spray device so as to cover the LED chip and the wiring of the LED element.

[Comparative Example 3]
In the same manner as in Example 1, a polysiloxane-containing solution was prepared. An LED device was obtained in the same manner as in Example 1 except that the polysiloxane-containing solution was applied by a spray device so as to cover the LED chip and the wiring of the LED element.

[Comparative Example 4]
In the same manner as in Example 1, a polysiloxane-containing solution was prepared. The polysiloxane-containing solution and 5 parts by mass of a silane coupling agent (aminopropyltrimethoxysilane) were mixed to prepare an LED device sealing agent. The polysiloxane compound-containing solution was added so that the amount of the polysiloxane compound was 95 parts by mass.

[Comparative Example 5]
Difunctional component: Trifunctional component: Tetrafunctional component As in Example 1, except that the amount of dimethyldimethoxysilane was 25.9 g, the amount of methyltrimethoxysilane was 17.6 g, and the amount of tetramethoxysilane was 13.1 g. A polysiloxane-containing solution containing a polysiloxane compound (polymerization molar ratio) = 5: 3: 2 was obtained. LED was applied in the same manner as in Example 1 except that the polysiloxane-containing solution was applied with a spray device so as to cover the LED chip and the wiring of the LED element and dried at 150 ° C. for 1 hour to form a sealing layer. Got the device.

[Evaluation]
(Evaluation of sealant for LED device)
The sealing agent for LED devices obtained in each Example and Comparative Example was evaluated as follows. The LED device sealant was dropped on a Teflon (registered trademark) petri dish having a diameter of 5 cm and held at 65 ° C. for 12 hours, and then cured at 150 ° C. for 3 hours. The cured sample was pulverized and subjected to solid Si-NMR measurement under the following conditions, and the waveform analysis of the obtained data was performed.

<Solid Si-NMR apparatus conditions>
Apparatus: Chemmagnetics Infinity CMX-400 nuclear magnetic resonance spectrometer ²⁹ Si resonance frequency: 79.436 MHz
Probe: 7.5 mmφ CP / MAS probe Measurement temperature: room temperature Sample rotation speed: 4 kHz
Measurement method: Single pulse method ¹ H decoupling frequency: 50 kHz
²⁹ Si flip angle: 90 ° ²⁹ Si90 ° pulse width: 5.0μs
Repeat time: 600s
Integration count: 128 Observation width: 30 kHz
Broadening factor: 20Hz

<Waveform analysis>
Data measured by solid-state Si-NMR was processed as follows.
For each data, 512 points were taken as measurement data, zero-filled to 8192 points, and Fourier transformed.
For each peak of the spectrum after Fourier transform, optimization calculation was performed by a non-linear least square method using the center position, height, and half width of the peak shape created by Lorentz waveform and Gaussian waveform or a mixture of both as variable parameters. The peak is identified by AIChEJournal, 44 (5), p. Reference was made to 1141, 1998, etc.

From the obtained waveform data, the half-value width, and the chemical shift -80ppm or more -40ppm peaks present in the following areas of the peaks present in the following areas chemical shift -120ppm or -90 ppm ^{(Q n} peak group) (T The half width of ( ⁿ peak group) was determined. Moreover, the ratio of the peak area derived from silanol to the total peak area was determined, and the silanol content (%) was determined.

(Evaluation of LED device)
<Sulfurization resistance evaluation>
The LED devices fabricated in each of the examples and comparative examples were stored for 48 hours in an environment with a hydrogen sulfide concentration of 10 to 15 volume ppm, 25 ° C., and humidity of 75% Rh. For the LED device, the total luminous flux value before and after the test was measured, and the ratio of the total luminous flux value after the test to the total luminous flux value before the test was calculated. The total luminous flux was measured with a spectral radiance meter (CS-2000, manufactured by Konica Minolta Sensing).

<Heat heat resistance evaluation>
The LED devices fabricated in each example and comparative example were stored for 1000 hours in an environment of 85 ° C. and humidity of 85% Rh. For the LED device, the total luminous flux value before and after the test was measured, and the ratio of the total luminous flux value after the test to the total luminous flux value before the test was calculated. The total luminous flux was measured with a spectral radiance meter (CS-2000, manufactured by Konica Minolta Sensing).

As shown in Table 1, when the sealing layer was not formed, the total luminous flux greatly decreased after the sulfidation resistance test and the wet heat resistance test (Comparative Example 1). On the other hand, even when forming the sealing layer, the half-value width of the solid Si-NMR ^{Q n} peak group of the spectrum of the cured film of the LED device sealing agent (peaks present in the following areas chemical shift -120ppm than -90 ppm) , and ^{T n} peak group when the half width of the (chemical shift -80ppm or more -40ppm following peaks present in the region) is too narrow, poor sulphide resistance and wet heat resistance (Comparative example 2). In this example, it is inferred that the bond angle distortion (half width) was small because many organic groups derived from the trifunctional silane compound remained in the film and sufficient siloxane bonds were not formed. However, since the crosslinking density was low and the film was not dense, the resistance to sulfidation and heat-and-moisture resistance were low.

Also, half of the ^{Q n} peak group half width, and ^{T n} peak group (peak present in the following areas chemical shift -80ppm least -40ppm group) of (Chemical peaks present in the shift -120ppm than -90ppm following areas) Even when the value range was 5 to 12 ppm, when the silane coupling agent and metal oxide fine particles were not contained in the LED device sealant, the resistance to sulfidation and moist heat resistance were poor (Comparative Examples 3 and 4). The stress generated during the dehydration condensation of the siloxane compound is not relieved, cracks are generated in the sealing layer, and the adhesiveness between the sealing layer and the wavelength conversion layer and the adhesiveness between the sealing layer and the LED element are insufficient. Inferred.

Furthermore, when the silanol content of the cured film of the LED device sealant was too high (Comparative Example 5), the resistance to sulfurization and heat-and-moisture resistance were also low. In this example, it is surmised that the LED device sealant was not sufficiently dried and a dense film was not formed.

The LED device manufactured using the sealant for an LED device of the present invention has high gas barrier properties and light extraction properties. Therefore, both can be applied to indoor and outdoor lighting devices.

1 Substrate (package)
2 LED chip 3 Metal reflective layer 4 Wire 5 Sealing layer 6 Wavelength conversion layer 7 Projection electrode 100 LED device

Claims

An LED device encapsulant comprising a polysiloxane compound, a silane coupling agent, and metal oxide fine particles,
The solid Si-nuclear magnetic resonance spectrum of the cured film obtained by holding the sealant for LED device at 65 ° C. for 12 hours and then hardening at 150 ° C. for 3 hours shows that the peak top position is chemical shift −120 ppm or more − The peak in the region of 90 ppm or less and the full width at half maximum of 5.0 ppm to 12 ppm and the peak top position is in the region of chemical shift of −80 ppm to −40 ppm and the full width at half maximum is greater than 5.0 ppm. Having a peak of 12 ppm or less,
The silanol content of the cured film is more than 10% by mass and 30% by mass or less.
Sealant for LED device.
The sealant for an LED device according to claim 1, further comprising an organometallic compound containing a metal element other than Si.
The LED device encapsulant according to claim 1 or 2, wherein the cured product of the organometallic compound has a refractive index of 1.48 or more.
An LED element, a sealing layer that covers the LED element, and a wavelength conversion layer that is formed on the sealing layer and includes a transparent resin and phosphor particles;
An LED device, wherein the sealing layer is a cured film of the sealant for an LED device according to any one of claims 1 to 3.