JP2014122296A - Sealing material precursor solution for light-emitting device, sealing material for light-emitting device using the same, led device, and method for producing the led device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing material precursor solution for a light-emitting device, with which a film without crack, having high adhesion to a light-emitting element and further being dense can be formed, and an LED device including a cured film thereof.SOLUTION: A sealing material precursor solution for a light-emitting device includes: a first polysiloxane produced by copolymerizing a trifunctional monomethyl silane compound and a tetrafunctional silane compound and having a mass-average molecular weight of 1,000 to 3,000; a second polysiloxane produced by copolymerizing a difunctional dimethyl silane compound, a trifunctional monomethyl silane compound, and a tetrafunctional silane compound and having a mass-average molecular weight of 1,000 to 3,000; and a solvent, in which the content of the first polysiloxane with respect to 100 pts.mass of the total amount of the first polysiloxane and the second polysiloxane is 20-80 pts.mass and the content of the second polysiloxane is 20-80 pts.mass.

Description

  The present invention relates to a precursor solution for sealing a light emitting element of a light emitting device, an LED device including a cured film thereof, and the like.

  In recent years, a white light emitting device in which a phosphor such as a YAG (yttrium, aluminum, garnet) phosphor is disposed in the vicinity of a gallium nitride (GaN) blue LED (Light Emitting Diode) chip has been widely used. In such a white light emitting device, white light is obtained by mixing blue light emitted from a blue LED chip and yellow light emitted from a phosphor upon receiving blue light. Further, it has been studied to obtain white light by mixing blue light emitted from a blue LED chip with red light, green light, or the like emitted from a phosphor upon receiving blue light.

  Such a white light emitting device is applied in various fields. For example, a white light emitting device is widely used as an alternative to conventional fluorescent lamps and incandescent lamps. White light emitting devices are also being applied to lighting devices that require extremely high luminance, such as automobile headlights.

  In such a light emitting device, it is common to seal a light emitting element (for example, an LED (Light Emitting Diode) element) with a transparent resin or the like. When the light-emitting element is sealed with a resin or the like, corrosion of the metal member included in the light-emitting element is suppressed, and the moisture and heat resistance of the light-emitting device is increased. One common resin for sealing a light emitting element is a silicone resin. Silicone resin has high heat resistance and ultraviolet light resistance. In particular, phenyl silicone resin has high resistance to sulfurization. However, a light-emitting device used in an outdoor environment is required to have higher gas barrier properties, and sealing with a conventional sealing material has insufficient gas barrier properties. Further, in sealing with a resin such as a silicone resin, the adhesion between the light emitting element and the sealing resin is often insufficient.

  Here, sealing a light-emitting element with a polymer (polysiloxane) of a tetrafunctional silane compound has also been studied. However, the tetrafunctional silane compound has a large shrinkage during curing (polycondensation). Therefore, there is a problem that cracks are likely to occur in the obtained film, and the gas barrier property of the sealing material is not sufficiently increased.

  On the other hand, Patent Documents 1 and 2 propose that a light-emitting element is sealed with a bifunctional silane compound and a copolymer (polysiloxane) of a trifunctional silane compound. In this technique, the occurrence of cracks is suppressed by including a certain amount or more of bifunctional components in the copolymer.

JP 2007-112974 A Japanese Patent Laid-Open No. 2007-112975

  The sealing materials described in Patent Documents 1 and 2 have few cracks and can be increased in thickness. However, there is a problem that the adhesiveness between the light emitting element and the sealing material is insufficient and it is easily peeled off by a thermal shock.

  An object of the present invention is to provide a sealing material precursor solution for a light-emitting device that is free from cracks, has high adhesion with a light-emitting element, and can form a dense film, and an LED device including the cured film. And

1st of this invention is related with the following sealing material precursor solutions for light emitting devices.
[1] A first polysiloxane having a mass average molecular weight of 1000 to 3000 obtained by copolymerization of a trifunctional monomethylsilane compound and a tetrafunctional silane compound, a bifunctional dimethylsilane compound, a trifunctional monomethylsilane compound, and a tetrafunctional silane compound. It contains a polymerized second polysiloxane having a weight average molecular weight of 1000 to 3000 and a solvent, and the content ratio of the first polysiloxane to the total amount of 100 parts by mass of the first polysiloxane and the second polysiloxane is 20 The sealing material precursor solution for light-emitting devices whose content rate of -80 mass parts and 2nd polysiloxane is 20-80 mass parts.
[2] The light emitting device according to [1], wherein a silicon content of a cured reaction product obtained by curing reaction of the first polysiloxane and the second polysiloxane at the content ratio is 20% by mass or more. Encapsulant precursor solution.

2nd of this invention is related with the following sealing materials for light-emitting devices.
[3] A light-emitting device sealing material for sealing a light-emitting element, obtained by curing the light-emitting device sealing material precursor solution according to [1] or [2],
The ratio of the number of moles of silicon atoms bonded with four oxygen atoms to the total number of moles of silicon atoms, as measured by solid Si-nuclear magnetic resonance spectrum, is 25 to 60%,
The ratio of the number of moles of silicon atoms having only three oxygen atoms bonded to the total number of moles of silicon atoms, as measured by solid-state Si-nuclear magnetic resonance spectrum, is 25 to 60%,
The ratio of the number of moles of silicon atoms in which only two oxygen atoms are bonded to the total number of moles of silicon atoms, as measured by solid Si-nuclear magnetic resonance spectrum, is 5% or more and less than 30%. .
[4] The sealing material for light emitting device according to [3], further containing phosphor particles.
[5] The sealing material for a light emitting device according to [3] or [4], wherein the light emitting element is an LED element.

The third aspect of the present invention relates to the following LED device.
[6] An LED device comprising: an LED element; a sealing layer covering the LED element; and a phosphor-containing resin layer containing a resin and phosphor particles formed on the sealing layer, The LED device which a sealing layer consists of hardened | cured material of the sealing material precursor solution for light-emitting devices as described in said [1] or [2], and the thickness of the said sealing layer is 0.5 micrometer or more and 15 micrometers or less.
[7] An LED device having an LED element and a sealing layer that covers the LED element and includes phosphor particles, wherein the sealing layer is the light-emitting device according to [1] or [2] LED device which contains the hardened | cured material of the sealing material precursor solution for water, and the thickness of the said sealing layer is 10 micrometers or more and less than 500 micrometers.

4th of this invention is related with the manufacturing method of the following LED devices.
[8] A step of preparing an LED element, a step of applying the encapsulant precursor solution for a light emitting device according to [1] or [2] on the LED element, and the encapsulant precursor for the light emitting device And a step of curing the solution at 100 ° C. or higher.

  According to the sealing material precursor solution for a light-emitting device of the present invention, a dense cured film having high adhesion to the light-emitting element, hardly generating cracks, and the like can be obtained. Therefore, the light-emitting device including the cured film has little deterioration over a long period of time and has high reliability.

It is an example of the solid Si-NMR spectrum of the sealing material for light emitting devices of this invention. 2A is a schematic cross-sectional view showing the configuration of the first LED device, FIG. 2B is a schematic cross-sectional view showing the configuration of the second LED device, and FIG. FIG. 5 is a schematic cross-sectional view showing a configuration of a third LED device.

  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 of the present invention.

1. Encapsulant precursor solution for light emitting device The encapsulant precursor solution for light emitting device of the present invention (hereinafter also simply referred to as “precursor solution”) is a film forming material for a sealing layer for sealing a light emitting element. It is. The precursor solution contains two types of polysiloxanes (first polysiloxane and second polysiloxane) and a solvent, and if necessary, phosphor particles, inorganic fine particles, phosphor particles, and silane. A coupling agent or the like may be included.

  As described above, it has been studied to form a sealing material by polymerizing a tetrafunctional silane compound. However, the tetrafunctional silane compound has a large shrinkage during curing (polycondensation), and cracks are likely to occur in the resulting film. Therefore, a film having a sufficient gas barrier property cannot be obtained.

  On the other hand, a bifunctional or trifunctional silane compound copolymer hardly causes cracks, but has low adhesion between the film and the light emitting element. Further, even when a tetrafunctional silane compound is polymerized together with a bifunctional silane compound or a trifunctional silane compound, the adhesion between the film and the light emitting element is not sufficiently increased. Furthermore, since a copolymer of a bifunctional or trifunctional silane compound contains many organic groups derived from these compounds, the film does not become dense. Therefore, there is a problem that sufficient gas barrier properties cannot be obtained. That is, in the conventional method, it is difficult to obtain a dense film (sealing material) with few cracks and high adhesion to the light emitting element.

  On the other hand, the cured film (sealing material) of the precursor solution of the present invention has good adhesion to the light emitting element, and cracks are hardly generated. Furthermore, since the film is dense, it is excellent in resistance to sulfur gas and light resistance. The mechanism for obtaining such characteristics is considered as follows.

  The first polysiloxane contained in the precursor solution of the present invention is a copolymer of a trifunctional monomethylsilane compound and a tetrafunctional silane compound, and the copolymer forms a dense film. In addition, silanol groups generated by hydrolysis of polysiloxane form siloxane bonds with hydroxyl groups on the surface of the light emitting element. Therefore, the adhesiveness between the cured product and the light emitting element is very high. However, the cured product of the first polysiloxane is brittle. Furthermore, since the first polysiloxane tends to shrink during polycondensation, cracks are likely to occur in the cured product.

  On the other hand, the second polysiloxane contained in the precursor solution is a copolymer of a bifunctional dimethylsilane compound, a trifunctional monomethylsilane compound, and a tetrafunctional silane compound. The cured product of the second polysiloxane contains a methyl group derived from a bifunctional dimethylsilane compound or a trifunctional monomethylsilane compound. Therefore, the cured product is flexible. In addition, the second polysiloxane does not easily shrink during polycondensation, and cracks hardly occur in the cured product. However, the cured product of the second polysiloxane has a low crosslink density and further has low adhesion to the light emitting element.

  When such a precursor solution containing the first polysiloxane and the second polysiloxane is cured, the curing speed of each polysiloxane is different, so that each polysiloxane is distributed in a cluster. Specifically, the first polysiloxane having a high curing rate is cured first, and the second polysiloxane is cured around the cured product.

  At this time, the cluster made of the first polysiloxane is firmly adhered to the light emitting element. And after hardening of 1st polysiloxane, it hardens | cures so that the 2nd polysiloxane with a slow reaction may fill the space | gap produced by hardening shrinkage | contraction of 1st polysiloxane. Therefore, a film having high adhesion between the cured film and the light emitting element and having no cracks can be obtained.

1-1) First polysiloxane The first polysiloxane contained in the precursor solution is a compound obtained by copolymerizing a trifunctional monomethylsilane compound and a tetrafunctional silane compound. The mass average molecular weight of the first polysiloxane is 1000 to 3000, preferably 1200 to 2700, and more preferably 1500 to 2000. When the mass average molecular weight of the first polysiloxane is less than 1000, the viscosity of the precursor solution becomes low, and liquid repellency or the like tends to occur when the precursor solution is applied. On the other hand, when the mass average molecular weight of the first polysiloxane exceeds 3000, the viscosity of the precursor solution increases, and it may be difficult to form a uniform film. In some cases, the film cannot be formed along the unevenness of the surface of the light emitting element. The mass average molecular weight is a value (polystyrene conversion) measured by gel permeation chromatography.

  The polymerization ratio (mole) of the trifunctional monomethylsilane compound and the tetrafunctional silane compound in the first polysiloxane is preferably 20:80 to 70:30, more preferably 40:60 to 65:35. Yes, more preferably 50:50 to 60:40.

  When the polymerization ratio of the tetrafunctional silane compound is less than 40 mol%, the adhesion between the light-emitting element and the cluster made of the cured product of the first polysiloxane may be insufficient. Furthermore, the curing rate of the first polysiloxane may be slow. On the other hand, when the polymerization ratio of the tetrafunctional silane compound exceeds 80 mol%, the curing shrinkage of the first polysiloxane becomes very large, and even when combined with the second polysiloxane, the cured film may be cracked. .

  The content ratio of the first polysiloxane with respect to 100 parts by mass of the total amount of the first polysiloxane and the second polysiloxane in the precursor solution is 20 to 80 parts by mass, preferably 35 to 60 parts by mass, Preferably it is 30-40 mass parts. When the content ratio of the first polysiloxane is less than 20 parts by mass, the amount of the cluster composed of the cured product of the first polysiloxane is small, and the adhesion between the cured film of the precursor solution and the light emitting element is not sufficiently increased. Therefore, the cured film may be peeled off due to thermal shock or the like. On the other hand, when the content ratio of the first polysiloxane exceeds 80 parts by mass, the flexibility of the cured film is lowered. Furthermore, since the amount of the second polysiloxane is relatively small, and voids generated by the curing shrinkage of the first polysiloxane are not filled with the second polysiloxane, the film is likely to crack. As a result, the gas barrier property of the cured film may be reduced.

The trifunctional monomethylsilane compound constituting the first polysiloxane may be a compound represented by the following general formula (I).
Si (OR ¹ ) ₃ CH ₃ (I)
In the general formula (I), OR ¹ represents a hydrolyzable group. The hydrolyzable group refers to a group that is hydrolyzed with water to generate a highly reactive hydroxyl group. Examples of the hydrolyzable group include an alkoxy group, an acetoxy group, a butanoxime group, a phenoxy group, and the like. One of these hydrolyzable groups may be contained alone, or two or more thereof may be contained. Among them, since the component that is liberated after the formation of polysiloxane is neutral, the hydrolyzable group is more preferably a lower alkoxy group having 1 to 5 carbon atoms or a phenoxy group, and more preferably a methoxy group or an ethoxy group. .

  Specific examples of the trifunctional monomethylsilane compound constituting the first polysiloxane include methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, methyltripentyloxysilane, methylmonomethoxydiethoxysilane, and methylmonomethoxy. Dipropoxysilane, methylmonomethoxydipentyloxysilane, methylmonomethoxydiphenyloxysilane, methylmethoxyethoxypropoxysilane, methylmonomethoxymonoethoxymonobutoxysilane and the like are included. Among these, methyltrimethoxysilane and methyltriethoxysilane are preferable, and methyltrimethoxysilane is more preferable.

The tetrafunctional silane compound constituting the first polysiloxane may be a compound represented by the following general formula (II).
Si (OR ² ) ₄ (II)
In the general formula (II), OR ² represents a hydrolyzable group. Examples of the hydrolyzable group include a lower alkoxy group having 1 to 5 carbon atoms, an acetoxy group, a butanoxime group, a phenoxy group, and the like. One of these hydrolyzable groups may be contained alone, or two or more thereof may be contained. Among them, since the component that is liberated after the formation of polysiloxane is neutral, the hydrolyzable group is more preferably a lower alkoxy group having 1 to 5 carbon atoms or a phenoxy group, and more preferably a methoxy group or an ethoxy group. .

  Specific examples of the tetrafunctional silane compound constituting the first polysiloxane include tetramethoxysilane, tetraethoxysilane, terapropoxysilane, tetrabutoxysilane, tetrapentyloxysilane, tetraphenyloxysilane, trimethoxymonoethoxysilane, Dimethoxydiethoxysilane, triethoxymonomethoxysilane, trimethoxymonopropoxysilane, monomethoxytributoxysilane, monomethoxytripentyloxysilane, monomethoxytriphenyloxysilane, dimethoxydipropoxysilane, tripropoxymonomethoxysilane, trimethoxy Monobutoxysilane, Dimethoxydibutoxysilane, Triethoxymonopropoxysilane, Diethoxydipropoxysilane, Tributoxymonopropoxysilane, Dimethyl Xymonoethoxymonobutoxysilane, diethoxymonomethoxymonobutoxysilane, diethoxymonopropoxymonobutoxysilane, dipropoxymonomethoxymonoethoxysilane, dipropoxymonomethoxymonobutoxysilane, dipropoxymonoethoxymonobutoxysilane, dibutoxymono Tetraalkoxysilanes such as methoxymonoethoxysilane, dibutoxymonoethoxymonopropoxysilane, monomethoxymonoethoxymonopropoxymonobutoxysilane and the like are included. Among these, tetramethoxysilane and tetraethoxysilane are preferable.

  The first polysiloxane is prepared by hydrolyzing the above-described trifunctional monomethylsilane compound and tetrafunctional silane compound in the presence of an acid catalyst, water, and an organic solvent, followed by a condensation reaction. The method for preparing the first polysiloxane will be described in detail later.

1-2) Second polysiloxane The second polysiloxane is a compound obtained by copolymerizing a bifunctional dimethylsilane compound, a trifunctional monomethylsilane compound, and a tetrafunctional silane compound. The mass average molecular weight of the second polysiloxane is 1000 to 3000, preferably 1200 to 2700, and more preferably 1500 to 2000. When the mass average molecular weight of the second polysiloxane is less than 1000, the viscosity of the precursor solution becomes low, and liquid repellency or the like is likely to occur when the precursor solution is applied. On the other hand, when the mass average molecular weight of the second polysiloxane exceeds 3000, the viscosity of the precursor solution increases and it may be difficult to form a uniform film. In some cases, the film cannot be formed along the unevenness of the surface of the light emitting element. The mass average molecular weight is a value (polystyrene conversion) measured by gel permeation chromatography.

  The polymerization ratio of the bifunctional dimethylsilane compound to the total number of moles of the bifunctional dimethylsilane compound, the trifunctional monomethylsilane compound, and the tetrafunctional silane compound in the second polysiloxane is preferably 10 to 70 mol%. More preferably, it is 30-70 mol%. When the polymerization ratio of the bifunctional dimethylsilane compound exceeds 70 mol%, the crosslink density of the polysiloxane becomes small and the sulfidation resistance tends to be low. On the other hand, when the polymerization amount of the bifunctional dimethylsilane compound is less than 10 mol%, the flexibility of the cured film of the precursor solution is lowered, and cracks are likely to occur in the cured film.

  The polymerization ratio of the trifunctional monomethylsilane compound to the total number of moles of the bifunctional dimethylsilane compound, the trifunctional monomethylsilane compound, and the tetrafunctional silane compound is preferably 10 to 70 mol%, more preferably 10 to 40 mol%. When the amount of the trifunctional monomethylsilane compound is in the above range, the balance between flexibility and denseness of the cured film of the precursor solution tends to be good.

  The polymerization ratio of the tetrafunctional silane compound to the total number of moles of the bifunctional dimethylsilane compound, the trifunctional monomethylsilane compound, and the tetrafunctional silane compound is preferably 10 to 70 mol%, more preferably 10 to 40 mol%. Mol%. If the amount of the tetrafunctional silane compound exceeds 70 mol%, cracks are likely to occur in the cured film of the precursor solution. On the other hand, when the amount of the tetrafunctional silane compound is less than 20 mol%, the denseness of the cured film of the precursor solution is lowered, and the gas barrier property may be lowered.

  The content ratio of the second polysiloxane with respect to 100 parts by mass of the total amount of the first polysiloxane and the second polysiloxane in the precursor solution is 20 to 80 parts by mass, preferably 40 to 75 parts by mass, Preferably it is 60-70 mass parts. When the content ratio of the second polysiloxane is less than 20 parts by mass, the void produced by the curing shrinkage of the first polysiloxane cannot be sufficiently filled with the second polysiloxane, and cracks are likely to occur in the film. On the other hand, when the content ratio of the second polysiloxane exceeds 80 parts by mass, the denseness of the cured film is lowered and the gas barrier property may be lowered. In addition, since the amount of clusters composed of the cured product of the first polysiloxane is relatively reduced, the adhesion between the cured film of the precursor solution and the light emitting element is not sufficiently enhanced.

  The trifunctional monomethylsilane compound and the tetrafunctional silane compound constituting the second polysiloxane can be the same as the trifunctional monomethylsilane compound and the tetrafunctional silane compound constituting the first polysiloxane.

On the other hand, the bifunctional dimethylsilane compound constituting the second polysiloxane may be a compound represented by the following general formula (III).
Si (OR ³ ) ₂ (CH ₃ ) ₂ (III)
In the general formula (III), OR ³ represents a hydrolyzable group. Examples of the hydrolyzable group include a lower alkoxy group having 1 to 5 carbon atoms, an acetoxy group, a butanoxime group, a phenoxy group, and the like. One of these hydrolyzable groups may be contained alone, or two or more thereof may be contained. Among them, since the component that is liberated after the formation of polysiloxane is neutral, the hydrolyzable group is more preferably a lower alkoxy group having 1 to 5 carbon atoms or a phenoxy group, and more preferably a methoxy group or an ethoxy group. .

  Specific examples of the bifunctional dimethylsilane compound constituting the second polysiloxane include dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, dichlorodiethoxysilane, and the like. Among these, methyltrimethoxysilane and dimethyldiethoxysilane are preferable, and dimethyldimethoxysilane is more preferable.

  The second polysiloxane is prepared by hydrolyzing a bifunctional dimethylsilane compound, a trifunctional monomethylsilane compound, and a tetrafunctional silane compound in the presence of an acid catalyst, water, and an organic solvent, followed by a condensation reaction. The method for preparing the second polysiloxane will be described in detail later.

1-3) Silicon content of the cured reaction product of the first polysiloxane and the second polysiloxane The first polysiloxane and the second polysiloxane are mixed in a proportion contained in the precursor solution. The silicon content of the cured reaction product obtained by curing is preferably 20% by mass or more, more preferably 25% by mass or more, and further preferably 30% by mass or more. On the other hand, the upper limit is 47% by mass because the silicon content of the glass composed solely of SiO ₂ is 47% by mass. The higher the silicon content of the cured product of the first polysiloxane and the second polysiloxane, the smaller the amount of organic machine remaining in the cured reaction product of the first polysiloxane and the second polysiloxane; This shows that a siloxane bond is formed. If the silicon content of the cured reaction product of the first polysiloxane and the second polysiloxane is 20% by mass or more, the gas barrier property of the cured film of the precursor solution is likely to increase, and the light resistance and heat resistance are also improved. Increased enough.

  The silicon content of the cured product of the first polysiloxane and the second polysiloxane depends on the polymerization ratio of the trifunctional monomethylsilane compound in the first polysiloxane, the bifunctional dimethylsilane compound and 3 in the second polysiloxane. It is adjusted by the polymerization ratio of the functional monomethylsilane compound and the mixing ratio of the first polysiloxane and the second polysiloxane. Specifically, if the polymerization ratio of the tetrafunctional silane compound is increased, the silicon content of the polymer is increased.

  The silicon content of the cured reaction product of the first polysiloxane and the second polysiloxane is measured by the following method. The first polysiloxane and the second polysiloxane are mixed in a content ratio contained in the precursor solution, and are cured at 150 ° C. for 60 minutes. This cured reaction product is fired in a platinum crucible in the air at 450 ° C. for 1 hour, then at 750 ° C. for 1 hour, and at 950 ° C. for 1.5 hours to remove the carbon component. To the resulting residue, 10 times or more amount of sodium carbonate is added and heated by a burner to melt. Thereafter, this is cooled, demineralized water is added, and the pH is adjusted to neutral with hydrochloric acid. Then, the volume is calculated by conducting a constant volume adjustment so that the concentration of silicon is about several ppm, and performing inductively coupled plasma spectroscopy (hereinafter abbreviated as “ICP” where appropriate).

1-4) Method for preparing first polysiloxane and second polysiloxane The first polysiloxane described above comprises a trifunctional monomethylsilane compound and a tetrafunctional silane compound in the presence of an acid catalyst, water, and an organic solvent. It is prepared by hydrolysis and condensation reaction. The second polysiloxane is prepared by hydrolyzing a bifunctional dimethylsilane compound, a trifunctional monomethylsilane compound, and a tetrafunctional silane compound in the presence of an acid catalyst, water, and an organic solvent, followed by a condensation reaction. . The mass average molecular weight of each polysiloxane obtained can be adjusted by reaction conditions (particularly reaction time) and the like.

  At the time of preparing the first polysiloxane, a trifunctional monomethylsilane compound and a tetrafunctional silane compound may be mixed at a predetermined ratio and copolymerized at random. Alternatively, after the trifunctional monomethylsilane compound is polymerized to some extent, the polymer may be copolymerized with a block, such as by copolymerizing a tetrafunctional silane compound. Similarly, at the time of preparing the second polysiloxane, a bifunctional dimethylsilane compound, a trifunctional monomethylsilane compound, and a tetrafunctional silane compound may be preliminarily mixed at a predetermined ratio and copolymerized randomly. Alternatively, after copolymerizing only a bifunctional dimethylsilane compound or a trifunctional monomethylsilane compound to some extent, this polymer may be copolymerized with a block, for example, by copolymerizing only a tetrafunctional silane compound.

  The acid catalyst added during the preparation of the first polysiloxane and the second polysiloxane may be any compound that hydrolyzes the silane compound in the presence of water, and may be either an organic acid or an inorganic acid.

  Examples of inorganic acids include sulfuric acid, phosphoric acid, nitric acid, hydrochloric acid, etc. Among them, phosphoric acid and nitric acid are preferable. Examples of organic acids include formic acid, oxalic acid, fumaric acid, maleic acid, glacial acetic acid, acetic anhydride, propionic acid, n-butyric acid and other carboxylic acid residues, and organic sulfonic acid and other sulfur-containing acid residues. The compound which has is included. Specific examples of the organic acid include organic sulfonic acid or esterified products thereof (organic sulfate ester, organic sulfite ester) and the like.

The acid catalyst is particularly preferably an organic sulfonic acid represented by the following general formula (IV).
R ⁴ —SO ₃ H (IV)
(In general formula (IV), R ⁴ is a hydrocarbon group which may have a substituent.)

In the general formula (IV), the hydrocarbon group represented by R ⁴ may be a linear, branched or cyclic hydrocarbon group having 1 to 20 carbon atoms. The hydrocarbon may be a saturated hydrocarbon or an unsaturated hydrocarbon. For example, it may have a substituent such as a halogen atom such as a fluorine atom, a sulfonic acid group, a carboxyl group, a hydroxyl group, an amino group, or a cyano group.

In the general formula (IV), examples of the cyclic hydrocarbon group represented by R ⁴ include an aromatic hydrocarbon group such as a phenyl group, a naphthyl group, or an anthryl group, and particularly preferably a phenyl group. . The aromatic hydrocarbon group may have a linear, branched, or cyclic, saturated or unsaturated hydrocarbon group having 1 to 20 carbon atoms as a substituent.

  The organic sulfonic acid represented by the general formula (IV) is preferably nonafluorobutanesulfonic acid, methanesulfonic acid, trifluoromethanesulfonic acid, dodecylbenzenesulfonic acid or a mixture thereof.

  The amount of the acid catalyst to be mixed during the preparation of the first polysiloxane and the second polysiloxane is preferably such that the concentration of the acid catalyst in the system in which the hydrolysis reaction of the silane compound is 1 to 1000 ppm, more preferably 5 -800 ppm.

  In addition, the film quality and storage stability of the polysiloxane vary depending on the amount of water mixed during preparation of the polysiloxane. Therefore, the water addition rate is adjusted according to the target film quality and the like. Here, the water addition rate is the number of moles of water molecules to be added relative to the number of moles of alkoxy groups of the silane compound added to the reaction system for preparing the first polysiloxane or the second polysiloxane. It is a percentage (%).

  The water addition rate is preferably 50 to 200%, more preferably 75 to 180%. By setting the water addition rate to 50% or more, the film quality of the cured film of the precursor solution is stabilized. Moreover, the storage stability of a precursor solution becomes favorable by setting it as 200% or less.

  Examples of solvents used in the preparation of the first polysiloxane and the second polysiloxane include monohydric alcohols such as methanol, ethanol, propanol and n-butanol; methyl-3-methoxypropionate, ethyl-3- Alkyl carboxylic acid esters such as ethoxypropionate; polyhydric alcohols such as ethylene glycol, diethylene glycol, 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 monopropyl ether, diethylene glycol Polyethylene alcohol monoethers such as tylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, or monoacetates thereof; methyl acetate, ethyl acetate, acetic acid Esters such as butyl; Ketones such as acetone, methyl ethyl ketone, methyl isoamyl ketone; ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dipropyl ether, ethylene glycol dibutyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, diethylene glycol dimethyl ether, Diethylene glycol di It contains etc.; Chirueteru, polyhydric alcohols ethers any polyhydric alcohol hydroxyl groups have alkyl ethers of diethylene glycol methyl ethyl ether. These may be used alone or in combination of two or more.

1-5) Solvent The precursor solution contains a solvent. The solvent may be an aqueous solvent having excellent compatibility with water, a non-aqueous solvent having low compatibility with water, or the like. The aqueous solvent having excellent compatibility with water may be alcohols such as methanol, ethanol, propanol and butanol.

  The precursor solution may include water. When water is contained in the precursor solution, the first polysiloxane and the second polysiloxane are sufficiently hydrolyzed. Furthermore, when the below-mentioned tabular grains are contained in the precursor solution, the tabular grains can be sufficiently swollen and the viscosity of the precursor solution can be increased. The amount of water contained in the precursor solution is preferably 10 to 120 parts by mass, more preferably 80 parts per 100 parts by mass of polysiloxane (the total of the first polysiloxane and the second polysiloxane). -100 mass parts. When water is contained in an amount of 10 parts by mass or more with respect to 100 parts by mass of polysiloxane, the polysiloxane can be sufficiently hydrolyzed and the cured film of the precursor solution has sufficient heat and heat resistance. On the other hand, when water is contained in an amount of more than 120 parts by mass with respect to 100 parts by mass of polysiloxane, hydrolysis may occur during storage of the precursor solution, and precipitates may be generated in the precursor solution. It is desirable that the water contained in the precursor solution does not contain impurities.

  The solvent contained in the precursor solution is also preferably an organic solvent having a boiling point of 150 ° C. or higher, such as ethylene glycol or propylene glycol. When an organic solvent having a boiling point of 150 ° C. or higher is contained, the storage stability of the precursor solution is improved. Moreover, when the organic solvent whose boiling point is 150 degreeC or more is contained, it can suppress that a precursor solution solidifies during application | coating of a precursor solution. On the other hand, the boiling point of the solvent contained in the precursor solution is preferably 250 ° C. or less from the viewpoint of the drying property of the precursor solution.

1-6) Silane Coupling Agent The precursor solution may contain a silane coupling agent. Hydroxyl groups that are expressed by hydrolysis of the silane coupling agent are subjected to dehydration condensation reaction with hydroxyl groups present on the surface of the light emitting element to form siloxane bonds. The hydroxyl group also reacts with polysiloxane (first polysiloxane and second polysiloxane) to form a siloxane bond. Therefore, when the silane coupling agent is contained in the precursor solution, the adhesion between the cured product of the precursor solution and the light emitting element is further enhanced.

一般式（Ｖ）において、Ｙは２価の有機基、Ｘは加水分解性基、Ｒはアルキレン基を表す。また、ｎは１〜３の整数を表す。 The silane coupling agent contained in the precursor solution may be a compound represented by the following general formula (V).

In general formula (V), Y represents a divalent organic group, X represents a hydrolyzable group, and R represents an alkylene group. N represents an integer of 1 to 3.

  In general formula (V), Y represents a divalent organic group. The divalent organic group represented by Y is an aliphatic group or alicyclic 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 aromatic group or an alicyclic aromatic group. These may have atoms or atomic groups such as O, N, and S as a linking group.

  Y in the general formula (V) may have a substituent. Substituents are, for example, atoms such as F, Cl, Br, I; vinyl group, methacryloxy group, acryloxy group, styryl group, mercapto group, epoxy group, epoxycyclohexyl group, glycidoxy group, amino group, cyano group, nitro group And an organic functional group such as a sulfonic acid group, a carboxy group, a hydroxy group, an acyl group, an alkoxy group, an imino group, and a phenyl group.

  In the general formula (V), X is a hydrolyzable group. 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. One of these hydrolyzable groups may be contained alone, or two or more thereof may be contained. Among these, since the component released after the reaction is neutral, the hydrolyzable group 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 (V), the alkylene group represented by R is 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. These may have an atom or atomic group such as O, N, and S as a linking group.

  Specific examples of the silane coupling agent include vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ- Glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-methacryloxy Propyltriethoxysilane, N-β- (aminoethyl) γ-aminopropylmethyldimethoxysilane, N-β- (aminoethyl) γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) γ-aminopropyltrie G Xysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyl-aminopropyltrimethoxysilane, γ-chloropropylmethoxysilane, γ-mercaptopropyltrimethoxysilane, γ- Mercaptopropylmethyldimethoxysilane, 3-trihydroxysilylmethylphosphonate sodium salt, nitroclotris (methylene) triphosphonic acid, tris (trimethylsilyl) phosphate, tris (trimethylsilyl) phosphite, diethylphosphate ethyltriethoxysilane and the like.

  The content of the silane coupling agent is preferably 0.1 to 5.0 mass%, more preferably 0.15 to 2.0 mass%, based on the total solid content of the precursor solution. More preferably, it is 0.2-1.0 mass%. When the silane coupling agent is contained in an amount of 0.1% by mass or more, the adhesion between the cured film of the precursor solution and the light emitting element is likely to be increased.

1-7) Organometallic compound The precursor solution may contain an organometallic compound comprising a metal alkoxide or metal chelate containing a group 4 or group 13 metal element. The metal in the organometallic compound forms a metalloxane bond with polysiloxane (first polysiloxane and second polysiloxane) or a hydroxyl group on the surface of the light-emitting element. As a result, the adhesion between the cured film of the precursor solution and the light emitting element is enhanced.

  Moreover, a part of the organometallic compound forms a nano-sized cluster in the cured film of the precursor solution. This nano-sized cluster functions as a photocatalyst that changes hydrogen sulfide gas with high metal corrosivity into sulfur dioxide gas with low corrosivity. Therefore, when an organometallic compound is contained in the precursor solution, the sulfidation resistance of the cured film of the precursor solution is further increased.

The organometallic compound contained in the precursor solution is preferably a compound represented by the following general formula (VI).
M ^{m +} X _n Y _mn (VI)
In general formula (V), M represents a Group 4 or Group 13 metal element. Moreover, in general formula (VI), m represents the valence of M and represents 3 or 4. In general formula (VI), n represents the number of X groups and is an integer of 2 or more and 4 or less. However, m ≧ n.

  In the general formula (VI), the metal element represented by M is preferably aluminum, zirconium, or titanium, and particularly preferably zirconium. Zirconium metal alkoxide or metal chelate does not have an absorption wavelength in an emission wavelength region of a general light-emitting element (particularly blue light (wavelength 420 nm to 485 nm)). Therefore, the cured film containing the zirconium-based metal element transmits the light emitted from the light emitting element without absorbing it.

  In the general formula (VI), X represents a hydrolyzable group. 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. One of these hydrolyzable groups may be contained alone, or two or more thereof may be contained. The hydrolyzable group is preferably a lower alkoxy group having 1 to 5 carbon atoms because the component liberated after the reaction is neutral.

  In the general formula (VI), Y represents a monovalent organic group. Examples of the monovalent organic group represented by Y include groups known as monovalent organic groups of so-called silane coupling agents. Specifically, the aliphatic group, alicyclic group, aromatic group, alicyclic group having 1 to 1000 carbon atoms, preferably 500 or less, more preferably 100 or less, further preferably 50 or less, and particularly preferably 6 or less. Represents an aromatic group. These may have atoms or atomic groups such as O, N, and S as a linking group. Among these, the monovalent group represented by Y is preferably a methyl group from the viewpoint that the light resistance and heat resistance of the cured film of the precursor solution are enhanced.

  The organic group represented by Y in the general formula (VI) may have a substituent. Substituents are, for example, atoms such as F, Cl, Br, I; vinyl group, methacryloxy group, acryloxy group, styryl group, mercapto group, epoxy group, epoxycyclohexyl group, glycidoxy group, amino group, cyano group, nitro group And an organic functional group such as a sulfonic acid group, a carboxy group, a hydroxy group, an acyl group, an alkoxy group, an imino group, and a phenyl group.

  Specific examples of the organometallic compound represented by the general formula (VI) include the following compounds. Examples of metal alkoxides or metal chelates containing elemental aluminum include aluminum triisopropoxide, aluminum tri-n-butoxide, aluminum tri-t-butoxide, aluminum triethoxide and the like.

  Examples of metal alkoxides or metal chelates containing elemental zirconium include zirconium tetramethoxide, zirconium tetraethoxide, zirconium tetra n-propoxide, zirconium tetra i-propoxide, zirconium tetra n-butoxide, zirconium tetra i-butoxide, Zirconium tetra-t-butoxide, zirconium dimethacrylate dibutoxide, dibutoxyzirconium bis (ethyl acetoacetate) and the like.

  Examples of metal alkoxides or metal chelates containing elemental titanium include titanium tetraisopropoxide, titanium tetra n-butoxide, titanium tetra i-butoxide, titanium methacrylate triisopropoxide, titanium tetramethoxypropoxide, titanium tetra n-propoxy. , Titanium tetraethoxide, titanium lactate, titanium bis (ethylhexoxy) bis (2-ethyl-3-hydroxyhexoxide), titanium acetylacetonate, and the like.

  However, the compounds exemplified above are some of the commercially available organometallic compounds that are readily available. The compounds shown are also applied to the present invention as the organometallic compounds.

  The content of the organometallic compound is preferably 5 to 100 parts by mass, and 8 to 40 parts by mass with respect to 100 parts by mass of the aforementioned polysiloxane (the total of the first polysiloxane and the second polysiloxane). More preferably, it is 10-15 mass parts. When the content of the organometallic compound is less than 5 parts by mass, the above-described adhesion improving effect and the like cannot be sufficiently obtained. On the other hand, when the content of the organometallic compound exceeds 100 parts by mass, the storage stability of the precursor solution tends to be lowered.

1-8) Inorganic fine particles The precursor solution may contain inorganic fine particles. When inorganic fine particles are contained in the precursor solution, the viscosity of the precursor solution increases and it becomes easy to apply the precursor solution. Moreover, when inorganic fine particles are contained in the precursor solution, the strength of the cured film of the precursor solution increases.

  Examples of the inorganic fine particles include oxide fine particles such as zirconium oxide, silicon oxide, titanium oxide, and zinc oxide (that is, inorganic oxide fine particles) and fluoride fine particles such as magnesium fluoride.

  The average particle size of the inorganic fine particles is preferably 1 nm or more and 50 μm or less. The average particle diameter of the inorganic fine particles is measured, for example, by a Coulter counter method.

The inorganic fine particles are preferably porous, and the specific surface area is preferably 200 m ² / g or more. If the inorganic fine particles are porous, the solvent enters the porous voids, and the viscosity of the precursor solution is effectively increased. However, the viscosity of the precursor solution is not simply determined by the amount of the inorganic fine particles, but varies depending on the ratio of the inorganic fine particles and the solvent, the amount of other components, and the like.

  The content of the inorganic fine particles is preferably 0.5 to 50% by mass, more preferably 1 to 40% by mass with respect to the total solid content of the precursor solution. When the amount of the inorganic fine particles is less than 0.5% by mass, the above-described thickening effect and the effect of improving the strength of the cured film cannot be obtained. On the other hand, when the amount of the inorganic fine particles exceeds 50% by mass, the strength of the cured film of the precursor solution is lowered.

  The surface of the inorganic fine particles may be treated with a silane coupling agent or a titanium coupling agent. By the surface treatment, compatibility between the inorganic fine particles and the polysiloxane or the solvent is increased.

1-9) Phosphor particles The precursor solution may contain phosphor particles as necessary. When phosphor particles are contained in the precursor solution, a layer containing phosphor particles can be easily formed.

  The phosphor particles can be excited by the wavelength (excitation wavelength) of light emitted from a light emitting element (for example, an LED chip) to emit fluorescence having a wavelength different from the excitation wavelength. For example, examples of the phosphor particles that emit yellow fluorescence include YAG (yttrium, aluminum, garnet) phosphors. The YAG phosphor can convert blue light (wavelength 420 nm to 485 nm) emitted from the blue light emitting element into yellow light (wavelength 550 nm to 650 nm).

  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 1350 to 1450 ° C. for 2 to 5 hours to obtain a sintered body.

  A mixed raw material having a predetermined composition is obtained by sufficiently mixing oxides of Y, Gd, Ce, Sm, Al, La, and Ga, or compounds that easily become oxides at high temperatures in a stoichiometric ratio. 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 type of the phosphor is not limited to the YAG phosphor, and may be another phosphor such as a non-garnet phosphor that does not contain Ce.

  The average 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 diameter of the phosphor particles is too large, the gap generated at the interface between the phosphor particles and the polysiloxane curing reaction product becomes large in the cured film of the precursor solution. Thereby, the intensity | strength of the cured film of a precursor solution falls. The average particle diameter of the phosphor particles can be measured, for example, by a Coulter counter method.

  The amount of phosphor particles contained in the precursor solution is preferably 60 to 95% by mass with respect to the total solid content of the precursor solution. Basically, the higher the concentration of the phosphor particles in the cured film of the precursor solution, the better. When the concentration of the phosphor particles is increased, the content ratio of the cured product of polysiloxane is decreased, and therefore the distribution of the phosphor particles in the cured film of the precursor solution tends to be uniform. Further, when the concentration of the phosphor particles is increased, a necessary amount of the phosphor particles can be disposed on the surface of the light emitting element even if the cured film of the precursor solution is thinned.

  Moreover, when the density | concentration of the fluorescent substance particle in the cured film of a precursor solution is high, since the fluorescent substance particles mutually adhere, the intensity | strength of the cured film of a precursor solution increases. Furthermore, when the concentration of the phosphor particles in the cured film is high, heat generated from the phosphor particles is easily dissipated from the cured film.

  On the other hand, if the concentration of the phosphor particles in the cured film of the precursor solution is too high (greater than 95% by mass), the content ratio of the cured product of polysiloxane is extremely reduced, and the phosphor particles are sufficiently removed. It may not be possible to keep it.

1-10) Tabular grains When the aforementioned phosphor particles are contained in the precursor solution, it is preferable that both the tabular grains are contained in the precursor solution. When tabular particles are contained in the precursor solution, the viscosity of the precursor solution is increased, and sedimentation of the phosphor particles is suppressed. Since the tabular grains form a card house structure in the precursor solution, the viscosity of the precursor solution increases even in a small amount. Further, since the tabular grains have a tabular shape, the strength of the cured film of the precursor solution increases when the precursor solution contains tabular grains.

  A typical example of the tabular grains contained in the precursor solution is lamellar clay mineral fine particles. The main component of the layered clay mineral fine particles is a layered silicate mineral, preferably a swellable clay mineral having a mica structure, a kaolinite structure, a smectite structure, etc., and a swellable clay mineral having a smectite structure rich in swelling properties. More preferred.

  The content of the tabular grains is preferably 0.5% by mass to 20% by mass and more preferably 0.5% by mass to 10% by mass with respect to the total solid content of the precursor solution. When the tabular grain content is less than 0.5% by mass, the above thickening and curing cannot be sufficiently obtained even if tabular grains are added. On the other hand, when the amount of tabular grains exceeds 20% by mass, the strength of the cured film of the precursor solution decreases.

  In consideration of the compatibility with the aforementioned solvent, the surface of the layered clay mineral fine particles may be modified (surface treatment) with an ammonium salt or the like.

1-11) pH and viscosity of precursor solution It is preferable that the pH of a precursor solution is 1-4. When the pH is less than 1 or exceeds 4, polysiloxane (first polysiloxane and second polysiloxane) or an organometallic compound may react, and precipitates may be generated during storage. The precursor solution may contain, for example, a pH adjusting agent such as nitric acid for pH adjustment.

  A preferable viscosity of the precursor solution is appropriately selected according to a coating method of the precursor solution. When the precursor solution is applied with a dispenser, the viscosity of the precursor solution is preferably 0.5 to 100 cP, more preferably 0.7 to 10 cP, and further preferably 1 to 5 cP. The viscosity is a value measured at 25 ° C. with a tuning fork type vibration viscometer. When the precursor solution is applied with a dispenser, if the viscosity of the precursor solution is too low, the precursor solution leaks from the needle during application, and it is difficult to adjust the application amount. On the other hand, when the viscosity of the precursor solution is too high, the precursor solution is not discharged from the needle. The viscosity of the precursor solution is adjusted by the amount of the solvent and the amount of inorganic fine particles.

  On the other hand, when the precursor solution is applied by spraying, the viscosity of the precursor solution is preferably 10 to 1000 cP, more preferably 12 to 800 cP, and further preferably 20 to 600 cP. When the precursor solution is applied by spraying, if the viscosity of the precursor solution is too low, the applied precursor solution flows, and it is difficult to form a coating film only in the target region. If the viscosity of the precursor solution is too high, the precursor solution cannot be discharged from the spray device. Furthermore, there are cases where a cured film cannot be formed along the unevenness of the light emitting element. The viscosity of the precursor solution is adjusted by the amount of the solvent and the amount of inorganic fine particles.

1-12) Method for Preparing Precursor Solution The precursor solution comprises a solvent, a first polysiloxane, a second polysiloxane, and, if necessary, a silane coupling agent, an organometallic compound, inorganic fine particles, and fluorescence. It is prepared by mixing body particles, tabular grains and the like. Stirring of the mixed solution can be performed by any method, and for example, stirring can be performed with a stirring mill, a blade kneading stirring device, a thin-film swirling disperser, or the like.

  In the case where the precursor solution contains tabular grains, 1) premixed tabular grains (which have been surface-treated oleophilically) in a dispersion solvent other than water, and then polysiloxane and organometallic Compound, phosphor particles, inorganic fine particles, and water are added and mixed, and stirred, or 2) Preliminary mixing of tabular particles (lipophilic surface-treated) and water, followed by polysiloxane, It is preferable to stir the organometallic compound, the phosphor particles, and the inorganic oxide together with a dispersion solvent other than water. Thus, when the tabular grains are uniformly dispersed, the viscosity of the precursor solution tends to increase.

2. Light-Emitting Device Sealant The light-emitting device sealant (hereinafter also simply referred to as “sealing material”) of the present invention is obtained by curing the above-described light-emitting device sealant precursor solution.

2-1) Characteristics of sealing material The sealing material is a member for sealing a light emitting element of a light emitting device, and has the following characteristics.

(I) The ratio of the number of moles of silicon atoms in which four oxygen atoms are bonded to the total number of moles of silicon atoms, as measured by a solid Si-nuclear magnetic resonance spectrum, is 25 to 60%. (Ii) The solid Si-nucleus The ratio of the number of moles of silicon atoms bonded with only three oxygen atoms to the total number of moles of silicon atoms, measured by magnetic resonance spectrum, is 25-60%. (Iii) measured by solid Si-nuclear magnetic resonance spectrum The ratio of the number of moles of silicon atoms in which only two oxygen atoms are bonded to the total number of moles of silicon atoms is 5% or more and less than 30%.

  The sealing material includes a cured product of the first polysiloxane and the second polysiloxane. Therefore, a silicon atom (generally referred to as “Q site”) to which four oxygen atoms are bonded is bonded to the sealing material; three oxygen atoms and one other atom (generally a carbon atom) are bonded. Silicon atom (generally referred to as “T site”); silicon atom (generally referred to as “D site”) in which two oxygen atoms and two other atoms (generally carbon atoms) are bonded. Included). The Q site is derived from a tetrafunctional silane compound, the T site is derived from a trifunctional monomethylsilane compound, and the D site is derived from a bifunctional dimethylsilane compound.

Here, a silicon atom (Q site) in which four oxygen atoms are bonded is an atom in which four -OSi are bonded (Q ⁴ ), an atom in which three -OSi and one -OH are bonded (Q ³ ) There is an atom (Q ² ) or the like in which two —OSi and two —OH are bonded. Then, when the solid Si-NMR measurement, peaks derived from the ^{Q 4 (Q 4} peak), peaks derived from ^{Q 3 (Q 3} peak), peaks derived from ^{Q 2 (Q 2} peaks), or the like, Q All the peaks derived from the sites have a peak top in the region of chemical shift of −130 to −80 ppm. These are also observed as continuous multimodal peaks. In the present invention, it is referring to these peaks and Q ⁿ peak group.

Similarly, there are several types of silicon atoms (T sites) in which three oxygen atoms are bonded. And when a solid Si-NMR measurement is performed, all the peaks derived from T site have a peak top in the region of a chemical shift of −80 to −40 ppm. These are also observed as continuous multimodal peaks. In the present invention, it is referring to these peaks and T ⁿ peak group.

Furthermore, there are several types of silicon atoms (D sites) in which two oxygen atoms are bonded. And when a solid Si-NMR measurement is performed, the peak originating in D site has a peak top in the area | region of -40 to -3 ppm of chemical shift. These are also observed as continuous multimodal peaks. In the present invention, referring to these peaks and D ⁿ peak group.

  FIG. 1 is an example of a solid Si-NMR spectrum of the sealing material of the present invention. The horizontal axis in FIG. 1 indicates chemical shift, and the vertical axis indicates “relative strength” depending on the abundance of each silicon contained in the sealing material. In FIG. 1, D11 is actually measured data, and D12 is data modeled by a Gaussian function.

As shown in FIG. 1, the spectrum of the solid Si-NMR of the sealing material of the present invention, ^{D n} peak group (P11), ^{T n} peak group (P12), and ^{Q n} peak group (P13) is detected Is done. The area ratio of the D ⁿ peak group, the T ⁿ peak group, and the Q ⁿ peak group in the spectrum is equal to the molar ratio of the D site, the T site, and the Q site. Further, the ratio of the area of each peak group to the total area of the Q ⁿ peak group, the T ⁿ peak group, and the D ⁿ peak group is the molar ratio of each site to the total molar amount of silicon atoms contained in the sealing material. Is equal to

As described above, (i) to the total molar amount of the silicon atoms contained in the sealing material of the present invention, the ratio of moles of Q sites; i.e., Q ⁿ peak group area / (Q ⁿ peak group, T ⁿ peaks, and ^{D n} the total area) × 100 of the peak group is 20 to 60%, preferably 25-50%, more preferably 30 to 40%.

  When the content ratio of the Q site is less than 25%, the amount of siloxane bonds formed between Si atoms contained in the encapsulant and the hydroxyl group on the surface of the light emitting element is reduced, and the encapsulant and the light emitting element are reduced. The adhesion of is not sufficiently improved. Further, when the content molar ratio of the Q site is small, the crosslink density of the cured product of polysiloxane is lowered, and the gas barrier property of the sealing material is lowered. On the other hand, when the content molar ratio of the Q site exceeds 60%, the flexibility of the sealing material is lowered, and cracks are likely to occur in the sealing material.

And (ii) the ratio of the number of moles of silicon atoms (T sites) in which only three oxygen atoms are bonded to the total mole amount of silicon atoms contained in the sealing material of the present invention; that is, the area of the ^Tn peak group / (Total area of Q ⁿ peak group, T ⁿ peak group, and D ⁿ peak group) × 100 is 20 to 60%, preferably 30 to 55%, more preferably 40 to 50%.

  When the molar ratio of the T site is less than 25%, the sealing material becomes insufficiently flexible, and cracks are likely to occur in the sealing material. On the other hand, when the molar ratio of the T site exceeds 60%, the molar ratio of the Q site is relatively reduced, and the adhesion between the sealing material and the light emitting element is not sufficiently increased. The trifunctional T site also forms a siloxane bond to some extent with the hydroxyl group on the surface of the light emitting element. However, the siloxane bond only by the T site is not sufficient, and the adhesion between the sealing material and the light emitting element is not sufficiently increased.

And (iii) the ratio of the number of moles of silicon atoms (D sites) in which only two oxygen atoms are bonded to the total mole amount of silicon atoms contained in the sealing material of the present invention; that is, the area of the D ⁿ peak group / (Total area of Q ⁿ peak group, T ⁿ peak group, and D ⁿ peak group) × 100 is 5% or more and less than 30%, preferably 15 to 25%, more preferably 18 to 20%.

  When the D site is included to some extent, the flexibility of the sealing material is increased and the occurrence of cracks is suppressed. However, when the molar ratio of the D site is 30% or more, a sufficient siloxane bond is not formed between the sealing material and the light emitting element, and sufficient adhesion between the sealing material and the light emitting element is obtained. I can't get it. Furthermore, the crosslinking density of the cured product of polysiloxane is lowered, and the gas barrier property of the sealing material is lowered. Furthermore, a large amount of organic groups remain in the encapsulant, and the encapsulant is likely to be discolored and heat resistance is reduced. On the other hand, if the molar ratio of the D site is less than 5%, the sealing material becomes less flexible and cracks are likely to occur in the sealing material. As a result, the gas barrier property of the sealing material is lowered.

  As described above, the Q site is derived from the tetrafunctional silane compound constituting the polysiloxane contained in the precursor solution, the T site is derived from the trifunctional monomethylsilane compound, and the D site is derived from the bifunctional dimethylsilane compound. Derived from. Therefore, the content molar ratio of the Q site, the content molar ratio of the T site, and the content molar ratio of the D site are the polymerization ratio of the tetrafunctional silane compound and the trifunctional monomethylsilane compound in the first polysiloxane, respectively. The polysiloxane is adjusted by the polymerization ratio of the tetrafunctional silane compound, the trifunctional monomethylsilane compound, and the bifunctional dimethylsilane compound in the polysiloxane, and further by the mixing ratio of the first polysiloxane and the second polysiloxane.

^{Q n} peak in the solid Si- nuclear magnetic resonance spectrum, ^{T n} peak, relative intensity of ^{D n} peak width 1/2 to become part of the peak value referred to as half-value width. When there are a plurality of peaks, waveform separation (peak separation) of the Si-NMR spectrum is performed by fitting using a Gaussian function or Lorentz function, and the relative intensity of each separated peak is ½ of the peak value. The width of the part to be is derived as the half width.

Also, ^{Q n} peak in the solid Si- nuclear magnetic resonance spectrum, ^{T n} peak, the smaller the half width of ^{D n} peak, the distribution of bond angle of the siloxane bond (Si-O-Si) is narrow. That is, it can be said that there is little distortion inside the sealing material.

Therefore, it is preferable that each half-width of the ^{Q n} peak detected in the spectrum of the solid Si-NMR is 5ppm or 12ppm or less, more preferably 6～11.5Ppm, more preferably from 8～11Ppm. It is preferable that each half-width of ^{T n} peak is also 5ppm or 12ppm or less, more preferably 7～11Ppm, more preferably from 8～10Ppm. It is preferable that each half-width of the ^{D n} peak is also 5ppm or 12ppm or less, more preferably 6～10Ppm, more preferably from 7～9Ppm.

The solid Si-NMR spectrum shown in Figure 1, the half-width of the ^{Q n} peak are each 11.1ppm and 6.8 ppm, the half-value width of ^{T n} peak is respectively 10.2ppm and 7.8 ppm, ^{D n} The half widths of the peaks are 8.0 ppm and 2.2 ppm, respectively. That is, the encapsulating material of the present invention includes a Q site, a T site, and a D site in which each half width of the peak of the Si-NMR spectrum is in a desired range.

2-2) Use of sealing material A sealing material is used for the sealing layer 7 of the LED device 100 as shown, for example in FIG.2 (C). In the LED device shown in FIG. 2C, the sealing layer 7 seals the LED element package 1, the metal part 2, the LED chip 3 and the like, and suppresses the corrosion of the LED chip 3 and the metal part 2 or the like. Take on. In the LED device 100 shown in FIG. 2C, a phosphor-containing resin layer 8 that converts the wavelength of light emitted from the LED chip 3 is further formed on the sealing layer 7. Therefore, it is not necessary for the sealing layer 7 to contain phosphor particles.

  On the other hand, the sealing material is also used for the sealing layer 6 of the LED device 100 as shown in FIG. In the LED device shown in FIG. 2B, the sealing layer 6 seals the LED element package 1, the metal part 2, the LED chip 3, and the like, and suppresses the corrosion of the LED chip 3 and the metal part 2 and the like. Take on. Further, the sealing layer 6 also has a wavelength conversion function for converting the wavelength of light emitted from the LED chip 3. Therefore, the phosphor layer is contained in the sealing layer 6.

2-3) Manufacturing method of sealing material The manufacturing method of the sealing material which does not contain phosphor particles includes the above-described first polysiloxane, second polysiloxane, solvent, silane coupling agent, inorganic fine particles, and the like. The precursor solution to be applied may be applied on the light emitting element and heated to 100 ° C. or higher to be cured.

  On the other hand, the method for producing the encapsulant containing the phosphor particles is 1) the first polysiloxane, the second polysiloxane, the solvent, the silane coupling agent, the inorganic fine particles, the phosphor particles, the tabular particles, etc. A method of applying the precursor solution contained on the light emitting element and curing it by heating to 100 ° C. or higher, or 2) arranging phosphor particles in advance on the light emitting element, and on the phosphor particles, It may be a method in which a precursor solution containing the first polysiloxane, the second polysiloxane, the solvent, the silane coupling agent, the inorganic fine particles and the like is applied and heated to 100 ° C. or more to be cured.

3. LED Device The above-described sealing material precursor solution for a light emitting device is used for forming a sealing layer of an LED device having an LED element and a sealing layer that covers the LED element. The structure of the LED element of the present invention includes the following three structures.

3-1) First LED device The first LED device has a structure shown in the schematic cross-sectional view of FIG. The first LED device 100 includes the LE element 10 and the sealing layer 6. The sealing layer 6 contains phosphor particles and functions to convert the wavelength of light from the LED chip into light of other wavelengths (hereinafter referred to as “wavelength conversion type sealing layer”).

3-1-1) LED Element The LED element 10 includes a package (LED substrate) 1, a metal part (metal wiring) 2, an LED chip 3 disposed in the package 1, a metal part 2, and an LED chip 3. And a glass substrate 5 that covers the light emitting surface of the LED chip 3.

  The package 1 of the LED element 10 may be, for example, a liquid crystal polymer or a ceramic, but the material is not particularly limited as long as it has insulating properties and heat resistance. Also, the shape is not particularly limited, and for example, as shown in FIG. 2 (A), it may be flat or concave.

  The emission wavelength of the LED chip 3 is not particularly limited. The LED chip 3 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 3 is not particularly limited. When the emission color of the LED chip 3 is blue, the LED chip 3 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) and a transparent electrode layer. The LED chip 3 may have a light emitting surface of 200 to 300 μm × 200 to 300 μm, for example. The height of the LED chip 3 is usually about 50 to 200 μm.

  The metal part 2 is made of a metal such as silver and reflects light emitted from the LED chip 3 to the light extraction surface side. The metal part 2 may also serve as metal wiring for supplying current to the LED chip 3.

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

  Moreover, the glass substrate 5 which covers the light emitting surface of the LED chip 3 is disposed for the purpose of protecting the LED chip. The thickness of the glass substrate is usually 200 to 2000 μm.

  In the LED device 100 shown in FIG. 2A, only one LED chip 3 is disposed in the package 1; however, a plurality of LED chips 3 may be disposed in the package 1.

3-1-2) Wavelength Conversion Type Sealing Layer The wavelength conversion type sealing layer 6 covers the metal part 2 and the glass substrate 5 that covers the light emitting surface of the LED chip 3. The wavelength conversion type sealing layer 6 contains phosphor particles, and in addition to protecting the LED chip 3 and the metal part 2 from hydrogen sulfide gas or the like, the light from the LED chip 3 is converted to light of other wavelengths. Play the role of converting.

  The thickness of the wavelength conversion type sealing layer 6 is not particularly limited, and is set according to the amount of phosphor required by the LED device 100. However, it is preferably thicker than the particle diameter of the phosphor particles and inorganic fine particles contained in the wavelength conversion type sealing layer 6. Specifically, it is preferably 10 μm or more, more preferably 15 μm or more, and further preferably 20 μm or more. If the thickness of the wavelength conversion type sealing layer 6 is less than 10 μm, the phosphor particles cannot be sufficiently held, and the phosphor particles may be peeled off. When the phosphor particles are peeled off, chromaticity variations are likely to occur in the irradiation light of the LED device. Further, when the phosphor particles are peeled off, voids are likely to be generated in the wavelength conversion type sealing layer 6, and the gas barrier property of the wavelength conversion type sealing layer 6 is also lowered. On the other hand, the thickness of the wavelength conversion type sealing layer 6 is preferably less than 500 μm. When the thickness of the wavelength conversion type sealing layer 6 is 500 μm or more, the optical path difference until the light from the light source passes through the wavelength conversion type sealing layer 6 increases near the center and the outer periphery of the LED device. Therefore, a difference is easily generated in the number of excited phosphor particles near the center and the outer periphery of the LED device. As a result, the chromaticity is likely to change near the center and the periphery of the LED device.

  The thickness of the wavelength conversion type sealing layer 6 means the maximum thickness of the layer disposed on the upper surface of the glass substrate 5. Moreover, the thickness of the wavelength conversion type sealing layer 6 formed on the glass substrate 5 means the maximum thickness. The thickness of the layer can be measured using a laser holo gauge.

3-2) Second LED Device The second LED device has a structure shown in the schematic cross-sectional view of FIG. The second LED device 100 includes the LE element 10 and the sealing layer 6. The sealing layer 6 contains phosphor particles and functions to convert the wavelength of light from the LED chip into light of other wavelengths. That is, it may be the same as the wavelength conversion type sealing layer 6 of the first LED device described above.

  The LED element 10 of the second LED device is connected to the package (LED substrate) 1, the metal part (metal wiring) 2, the LED chip 3 arranged in the package 1, and the metal part 2 and the LED chip 3. Projecting electrodes (bumps) 4 to be included. That is, the LED element 10 of the second LED device is the same as the LED element 10 of the first LED device except that there is no glass substrate 5 that protects the LED chip 3. 2B, only one LED chip 3 is disposed in the recess of the package 1 of the LED element 10 shown in FIG. 2B. However, a plurality of LED chips 3 may be disposed in the recess of the package 1. .

  The thickness of the wavelength conversion type sealing layer 6 in the second LED device means the maximum thickness of the layer disposed on the upper surface of the light emitting surface of the LED chip 3. Moreover, the thickness of the wavelength conversion type sealing layer 6 formed on the light emitting surface of the LED chip 3 means the maximum thickness. The thickness of the layer can be measured using a laser holo gauge.

3-3) Third LED Device The third LED device has a structure shown in the schematic cross-sectional view of FIG. The third LED device 100 includes an LE element 10, a sealing layer 7, and a wavelength conversion resin layer 8 that covers the sealing layer 7. In the third LED device 100, the wavelength conversion resin layer 8 contains phosphor particles and functions to convert the wavelength of light from the LED chip into light of other wavelengths.

3-3-1) LED element The LED element 10 of the third LED device includes a package (LED substrate) 1, a metal part (metal wiring) 2, an LED chip 3 arranged in the package 1, and a metal part. 2 and bump electrodes 4 that connect the LED chip 3 to each other. That is, the LED element 10 of the third LED device is the same as the LED element 10 of the second LED device. 2C, only one LED chip 3 is disposed in the recess of the package 1 of the LED element 10 shown in FIG. 2C. However, a plurality of LED chips 3 may be disposed in the recess of the package 1. .

3-3-2) Sealing layer The sealing layer 7 of the third LED device has a function of protecting the LED chip 3 and the metal part 2 of the LED element 10 from hydrogen sulfide gas and the like, and light from the LED device 100. It fulfills the function of increasing the extraction efficiency. When the phosphor-containing resin layer 8 is formed directly on the LED chip 3, the difference in refractive index between the LED chip 3 and the phosphor-containing resin layer 8 is large, so that the amount of light reflected at these interfaces increases. On the other hand, the refractive index of the sealing layer 7 is intermediate between the refractive index of the LED chip 3 and the refractive index of the phosphor-containing resin layer 8. Therefore, when the sealing layer 7 is included between the LED chip 3 and the phosphor-containing resin layer 8, the refractive index decreases in the order of the LED chip 3, the sealing layer 7, and the phosphor-containing resin layer 8. As a result, light reflection at the interface between the layers is suppressed, and the light extraction efficiency from the LED device 100 is increased.

  The thickness of the sealing layer 7 is not particularly limited, but is preferably thicker than the particle size of the inorganic fine particles contained in the sealing layer 7. Specifically, the thickness is preferably 0.5 μm to 15 μm, more preferably 0.6 to 1.5 μm, and still more preferably 0.7 to 0.95 μm. When the thickness of the wavelength conversion type sealing layer 6 is less than 0.5 μm, sufficient gas barrier properties cannot be obtained, and the LED element may deteriorate over time. On the other hand, when the thickness of the sealing layer 7 exceeds 15 μm, the sealing layer 7 tends to break, and there is a possibility that sufficient gas barrier properties cannot be obtained. The thickness of the sealing layer 7 means the maximum thickness of the sealing layer 7 disposed on the upper surface of the LED chip 3. The thickness of the sealing layer 7 can be measured using a laser holo gauge.

3-3-3) Phosphor-Containing Resin Layer The phosphor-containing resin layer 8 is a layer that converts light having a specific wavelength emitted from the LED chip 3 into light having another specific wavelength. The phosphor-containing resin layer 8 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 3 (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 3, a white LED device is obtained by adding phosphor particles that emit yellow fluorescence to the phosphor-containing resin layer 8. 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 a blue LED element as excitation light.

  The phosphor particles contained in the phosphor-containing resin layer 8 can be the same as the phosphor particles contained in the precursor solution for a light emitting device sealing material. Moreover, it is preferable that the quantity of the fluorescent substance particle contained in the fluorescent substance containing resin layer 8 is 5-15 mass% with respect to the total mass of the fluorescent substance containing resin layer 8, More preferably, it is 9-11 mass%. is there.

  The transparent resin contained in the phosphor-containing resin layer 8 is not particularly limited as long as it is a thermosetting resin that is 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; 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 is increased.

  The thickness of the phosphor-containing resin layer 8 is usually preferably 25 μm to 5 mm, more preferably 1 to 3 mm. If the phosphor-containing resin layer 8 is too thick, the phosphor particle concentration in the phosphor-containing resin layer 8 becomes excessively low, and the phosphor particles may not be uniformly dispersed.

[Application of LED device]
The LED device described above is further provided with other optical components (such as a lens) to form various optical members. In particular, since the LED device of the present invention is excellent in sulfur gas resistance, light resistance, heat resistance, and the like, it is suitable for lighting for vehicles, lighting for outdoor use, and the like.

4). Manufacturing method of LED device The manufacturing method of the LED device of this invention is demonstrated to the example of the method of manufacturing the above-mentioned 1st LED device and 3rd LED device.

4-1) Method for Manufacturing First LED Device The method for manufacturing the first LED device includes the following two steps.
1) Step of preparing the LED element 2) Applying the sealing material precursor solution for the light emitting device so as to cover the LED chip and the metal part, and curing the sealing material precursor solution for the light emitting device at 100 ° C. or more. Forming a wavelength conversion type sealing layer

4-1-1) LED element preparation process In the LED element preparation process, the LED element 10 is prepared. For example, it may be a step of electrically connecting the metal part 2 formed in the package 1 and the LED chip 3 and fixing the LED chip 3 to the package 1. The method for connecting the metal part 2 and the LED chip 3 and the method for fixing the LED chip 3 to the package 1 are not particularly limited, and may be the same as a conventionally known method.

4-1-2) Wavelength conversion type sealing layer forming step In the wavelength conversion type sealing layer forming step, a light emitting device sealing material precursor solution is applied and cured at a temperature of 100 ° C. or higher to obtain a wavelength conversion type. A sealing layer is formed.

  Here, when the phosphor particles are contained in the light emitting device sealing material precursor solution, the light emitting device sealing material precursor solution is directly applied onto the LED element (one liquid type). The encapsulant precursor solution for the light emitting device is applied so as to cover the metal part (metal wiring) 2 of the LED element, the side surface of the LED chip 3 arranged in the package 1, and the glass substrate 5. The means for coating is not particularly limited, but may be blade coating, spin coating coating, dispenser coating, spray coating, or the like. Spray coating is preferable because a thin coating film is easily formed and the wavelength conversion type sealing layer 6 is easily formed.

  After application of the encapsulant precursor solution for a light emitting device, the polysiloxane and the organometallic compound are 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, organic components and the like generated during polycondensation of the silane compound are not sufficiently removed, and the light resistance of the coating film may be lowered.

  On the other hand, when the phosphor particles are not included in the encapsulant precursor solution for the light emitting device, i) after applying the phosphor dispersion and arranging the phosphor particles so as to cover the LED element, ii) A sealing material precursor solution for a light emitting device is applied onto the phosphor particles (two-component type).

  The phosphor dispersion liquid may be a dispersion liquid in which phosphor particles and tabular particles are dispersed in a solvent. If necessary, inorganic fine particles and the like may be contained. The phosphor particles, tabular particles, and inorganic fine particles contained in the phosphor dispersion liquid may be the same as those contained in the above-described sealing material precursor solution for a light emitting device.

  The solvent contained in the phosphor dispersion is preferably an alcohol; it may be a monohydric alcohol such as methanol, ethanol, propanol, or butanol, or a dihydric or higher polyhydric alcohol. If a dihydric or higher alcohol is contained, the viscosity of the phosphor dispersion increases, and sedimentation of the phosphor particles is prevented. The dihydric or higher polyhydric alcohol is not particularly limited as long as the phosphor particles can be dispersed. Examples thereof include ethylene glycol, propylene glycol, diethylene glycol, glycerin, 1,3-butanediol, and 1,4- Examples include butanediol, preferably ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, and the like.

  The phosphor dispersion liquid may be applied so as to cover the metal part (metal wiring) 2 of the LED element 10, the side surface of the LED chip 3 disposed in the package 1, and the glass substrate 5. The application means is not particularly limited, and examples thereof include blade application, spin coat application, dispenser application, and spray application. In particular, spray coating and dispenser coating are preferable because a thin coating film can be easily formed. After application of the phosphor dispersion liquid, the coating film is dried as necessary.

  The thickness of the coating film after drying of the phosphor dispersion is preferably 5 to 250 μm, more preferably 20 to 100 μm, and still more preferably 30 to 50 μm. When the thickness of the coating film containing the phosphor particles is too thin, the thickness of the obtained wavelength conversion type sealing layer becomes thin.

  Thereafter, in the same manner as the one-component type described above, a light-emitting device sealing material precursor solution is applied and cured at 100 ° C. or higher to form a wavelength conversion type sealing layer.

  In addition, in the manufacturing method of the LED device of this invention, it is preferable to form the wavelength conversion type sealing layer 6 by a 2 liquid type rather than forming the wavelength conversion type sealing layer by a 1 liquid type. The storage stability of the two-pack type encapsulant precursor solution for light-emitting devices not containing phosphor particles is higher than the one-component type encapsulant precursor solution for phosphor devices containing phosphor particles. is there.

4-2) Third LED Device Manufacturing Method The LED device first LED device manufacturing method includes the following two steps.
1) Step of preparing the LED element 2) Applying the sealing material precursor solution for the light emitting device so as to cover the LED chip and the metal part, and curing the sealing material precursor solution for the light emitting device at 100 ° C. or more. And 3) forming a phosphor-containing resin layer containing phosphor particles and a transparent resin on the sealing layer.

4-2-1) LED Element Preparation Step In the LED element preparation step, the LED element 10 is prepared. For example, it may be a step of electrically connecting the metal part 2 formed in the package 1 and the LED chip 3 and fixing the LED chip 3 to the package 1. The method for connecting the metal part 2 and the LED chip 3 and the method for fixing the LED chip 3 to the package 1 are not particularly limited, and may be the same as a conventionally known method.

4-2-2) Sealing layer forming step In the sealing layer forming step, a wavelength conversion type sealing layer is formed by applying a sealing material precursor solution for a light emitting device and curing it at 100 ° C or higher. .

  Here, the sealing material precursor solution for the light emitting device is applied so as to cover the metal part (metal wiring) 2 of the LED element 10 and the light emitting surface and side surfaces of the LED chip 3 arranged in the package 1. The means for coating is not particularly limited, but may be blade coating, spin coating coating, dispenser coating, spray coating, or the like. Spray coating is preferable because a thin coating film is easily formed and the sealing layer 7 is easily formed.

  After application of the encapsulant precursor solution for a light emitting device, the polysiloxane and the organometallic compound are 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, organic components and the like generated during polycondensation of the silane compound are not sufficiently removed, and the light resistance of the coating film may be lowered.

4-2-3) Phosphor-containing resin layer forming step A phosphor-containing resin layer is formed on the aforementioned sealing layer. The phosphor-containing resin layer is obtained by preparing a phosphor-containing resin layer composition containing a transparent resin or a precursor thereof and phosphor particles, and applying and curing the composition on the sealing layer. .

  The composition for forming a phosphor-containing resin layer 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 may 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.

  Mixing of the phosphor-containing resin layer forming composition 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, sedimentation of the phosphor particles in the phosphor-containing resin layer forming composition can be suppressed.

  The method for applying the phosphor-containing resin 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.

<Solid Si-NMR measurement>
The encapsulant precursor solution for light emitting device prepared in each example and comparative example was applied on a slide glass washed with acetone with a spray device (TS-MSP-400, manufactured by Taitec Solutions), and 1 at 150 ° C. Baked for hours. The obtained cured film (sealing material) was pulverized, and a solid Si-nuclear magnetic resonance spectrum was measured under the following conditions.

(Equipment 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 Si 90 ° pulse width: 5.0μs
Repeat time: 600s
Integration count: 128 times Observation width: 30 kHz
Broadening factor: 20Hz

(Spectral 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. In addition, identification of a peak is AIChE Journal, 44 (5), p. Reference was made to 1141, 1998, etc.

(Calculation of molar ratio for each site)
From the obtained waveform data, peak groups present in the following areas chemical shift -130ppm least -80ppm area ^{(Q n} peak group), group of peaks present in the following areas chemical shift -80ppm over -40 ppm ^{(T n} peak area of the group), and -40ppm over -3ppm following peaks present in the region group the area of ^{(D n} peak group) was calculated.

And the content molar ratio of Q site in each sealing material, the content molar ratio of T site, and the content molar ratio of D site were calculated | required from the following formula | equation.
Content ratio of Q site = Q ⁿ peak group area / (total area of Q ⁿ peak group, T ⁿ peak group, and D ⁿ peak group) × 100
Content ratio of T site = area of T ⁿ peak group / (total area of Q ⁿ peak group, T ⁿ peak group, and D ⁿ peak group) × 100
Content molar ratio of D site = area of D ⁿ peak group / (total area of Q ⁿ peak group, T ⁿ peak group, and D ⁿ peak group) × 100

<Measurement of silicon content of cured reaction product of first polysiloxane and second polysiloxane>
The first polysiloxane and the second polysiloxane contained in the precursor solution for a light emitting device sealing material of each example and each comparative example were mixed in a proportion contained in the precursor solution, and this was mixed at 150 ° C. The curing reaction was performed for 60 minutes. The cured reaction product was pulverized to about 100 μm. This was calcined in a platinum crucible in the air at 450 ° C. for 1 hour, then at 750 ° C. for 1 hour, and at 950 ° C. for 1.5 hours to remove the carbon component. Add 10 times or more amount of sodium carbonate to a small amount of the residue obtained and heat it with a burner to melt it, cool it, add demineralized water, and adjust the pH to neutral with hydrochloric acid and add some silicon. The volume was adjusted to about ppm and ICP analysis was performed.

<Liquid repellency evaluation>
The encapsulant precursor solution for light emitting device prepared in each Example and Comparative Example was applied on the LED element with a wet film thickness of 8 μm by a spray device (TS-MSP-400; manufactured by Taitec Solutions). At this time, whether or not liquid droplets were formed on the light emitting surface of the LED chip, the silver reflector, and the resin package was evaluated according to the following criteria. The contact angle was measured with a contact angle meter DM-901 (manufactured by Kyowa Interface Science Co., Ltd.). In addition, in the case of the package (LED board | substrate) which has a recessed part, the side wall was cut | disconnected and evaluated.
○: No generation of droplets on the light emitting surface of the LED chip, the silver reflecting plate, and the resin package. Δ: No droplet generation on the light emitting surface of the LED chip and the silver reflecting plate, but the resin package. Drops with a contact angle of less than 40 ° are generated on top. ×: Droplets with a contact angle of 40 ° or more are generated on the light emitting surface of the LED chip, the silver reflector, and the resin package.

<Evaluation of film smoothness>
The encapsulant precursor solution for light emitting device prepared in each example and comparative example was applied on a slide glass washed with acetone with a spray device (TS-MSP-400, manufactured by Taitec Solutions), and 1 at 150 ° C. Baked for hours. The surface shape of the coating film was measured with a light interference type surface shape evaluator (WYKO NT9000, manufactured by Veeco), and the film smoothness was evaluated according to the following criteria.
○: Centerline average roughness Ra value of coating film is less than 200 nm Δ: Centerline average roughness Ra value of coating film is 200 nm or more and less than 250 nm ×: Centerline average roughness Ra value of coating film is 250 nm That's it

<Adhesion evaluation>
The heat shock test was done about the LED device produced by each Example and the comparative example. In the test, a cycle of −60 ° C. (30 minutes) and 120 ° C. (30 minutes) was repeatedly performed using a heat shock tester (TSA-42EL; manufactured by Espec Corp.). After this test, it was investigated whether or not the LED device was not lit due to peeling of the sealing layer (light-emitting device sealing material), and the adhesion was evaluated according to the following criteria.
◎: No lighting in 2000 cycles of heat shock ○: No lighting in 1500 cycles or more and less than 2000 cycles △: No lighting in 1000 cycles or more of heat shock, less than 1500 cycles Occurrence

<Sulfurization resistance evaluation>
About the LED device produced by each Example and the comparative example, sulfidation tolerance evaluation was performed based on the gas exposure test (JIS C 60068-2-43) of a JIS specification. The LED device was exposed to an environment of 15 ppm hydrogen sulfide gas, a temperature of 25 ° C., and a relative humidity of 75% RH for 1500 hours. The total luminous flux was measured for the LED devices before and after the exposure, and the resistance to sulfuration was evaluated according to the following criteria. The total luminous flux was measured with a spectral radiance meter (CS-2000, manufactured by Konica Minolta Sensing).
○: Total luminous flux to initial ratio (total luminous flux value after exposure to hydrogen sulfide gas / total luminous flux value before exposure to hydrogen sulfide gas × 100) is 96% or more Δ: total luminous flux to initial ratio (total luminous flux value after exposure to hydrogen sulfide gas) / Total luminous flux value before exposure to hydrogen sulfide gas × 100) is 92% or more and less than 96% ×: initial luminous flux to initial ratio (total luminous flux value after exposure to hydrogen sulfide gas / total luminous flux value before exposure to hydrogen sulfide gas × 100) 92% or less

<Crack resistance evaluation>
About the sealing layer of the LED device produced by each Example and the comparative example, the external appearance observation of the LED device was performed by SEM (VE7800, product made by Keyence) at 1000-times magnification. The crack resistance was evaluated according to the following criteria.
○: There are no cracks with a length of 5 μm or more in the coating film Δ: There are 1 to 5 cracks with a length of 5 μm or more in the coating film X: There are 5 or more cracks with a length of 5 μm or more in the coating film Have

<Light resistance evaluation>
The sealing material precursor solution for light emitting device was applied onto a slide glass and baked. At this time, lamination was performed so that the film thickness after firing was 1.5 μm. About the said slide glass, the transmittance | permeability before and behind processing for 150 mW and 100 hours with a metal halide lamp light resistance tester (M6T, Suga Test Instruments Co., Ltd.) was measured, and the light resistance was evaluated according to the following criteria.
-The average transmittance of light having a wavelength of 300 nm to 500 nm is reduced by less than 1.0% after the treatment.
・ After treatment, decrease in average transmittance of light having a wavelength of 300 nm to 500 nm is decreased by 1.0% or more and less than 1.5%.
-Reduction in average transmittance of light having a wavelength of 300 nm to 500 nm after treatment is reduced by 1.5% or more.

<Evaluation of chromaticity variation>
For the LED devices of the examples and comparative examples, (i) chromaticity of emitted light at the front of the LED device, (ii) chromaticity of emitted light when tilted 60 ° from the front of the LED device, (iii) from the front of the LED device The chromaticity of the emitted light when tilted by −60 ° (60 ° in the direction opposite to (ii)) was measured. The chromaticity was measured with a spectral radiance meter (CS-1000A, manufactured by Konica Minolta Sensing Co., Ltd.) for the x value and y value of the CIE color system. The z coordinate obtained from the relationship of x + y + z = 1 was omitted.
The standard deviation was determined for each measured chromaticity (x value and y value). And it evaluated by the average value of the standard deviation of x value, and the standard deviation of y value. The evaluation criteria are shown below.
-Average value of standard deviation is 0.01 or less: ○
The average value of standard deviation is greater than 0.01 and less than or equal to 0.02: Δ
-Average value of standard deviation is greater than 0.02: x

The phosphor used in each example and comparative example was prepared by the following method.
[Method for preparing phosphor]
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 in a reducing atmosphere in which hydrogen-containing nitrogen gas is circulated in a temperature range of 1350 to 1450 ° C. for 2 to 5 hours 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 size 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.

[LED Device Manufacturing Method (LED Devices A-1 to A-6)]
LED devices A-1 to A-6 were produced by the following method. These LED devices have a structure having the LED element 10 and the sealing layer 7 shown in FIG. In LED devices A-1 to A-6, the phosphor-containing resin layer 8 was not formed, and only the evaluation of the sealing material precursor solution for the light emitting device and its cured film (sealing layer) was performed. In the LED devices A-1 to A-6, usually, a phosphor-containing resin layer 8 similar to that of the LED device A-7 described later is formed.

(Example 1: Production of LED device A-1)
17.0 g of methyltrimethoxysilane, 19.0 g of tetramethoxysilane, 20.0 g of methanol, and 20.0 g of acetone were mixed and stirred. To the mixture, 27.3 g of water and 2.3 μL of 60% nitric acid were added, and the mixture was further stirred for 3 hours. Thereafter, it was aged at 26 ° C. for 2 days. The resulting composition was diluted with methanol so that the polysiloxane solid content was 10%. A first polysiloxane solution having a polymerization molar ratio of trifunctional monomethylsilane compound: tetrafunctional silane compound of 50:50, a mass average molecular weight of 1000, and a pH of 4 was obtained.

  Subsequently, 12.0 g of dimethoxydimethylsilane, 10.2 g of methyltrimethoxysilane, 11.4 g of tetramethoxysilane, 20.0 g of methanol, and 20.0 g of acetone were mixed and stirred. To the mixture, 27.3 g of water and 2.3 μL of 60% nitric acid were added, and the mixture was further stirred for 3 hours. Thereafter, it was aged at 26 ° C. for 2 days. The resulting composition was diluted with methanol so that the polysiloxane solid content was 10%. A second polysiloxane solution having a polymerization molar ratio of bifunctional dimethylsilane compound: trifunctional monomethylsilane compound: tetrafunctional silane compound of 40:30:30, a weight average molecular weight of 1000, and a pH of 4 is obtained. It was.

  Subsequently, the entire amounts of the first polysiloxane solution and the second polysiloxane solution were mixed and stirred with a stirrer for 30 minutes. This obtained the sealing material precursor solution for light emitting devices whose 1st polysiloxane: 2nd polysiloxane is mass ratio 50:50.

  On the other hand, the LED element which has a package (LED board | substrate) which has a recessed part shown by FIG.2 (C) was prepared. Specifically, an LED in which one blue LED chip (cuboid: 200 μm × 300 μm × 100 μm) is flip-chip mounted in the center of a housing portion of a circular package (opening diameter 3 mm, bottom diameter 2 mm, wall surface angle 60 °) An element was prepared.

  Subsequently, the above-described sealing material precursor solution for a light emitting device was applied by a spray device (TS-MSP-400, manufactured by Taitec Solutions) so as to cover the LED chip of the LED element. Then, the sealing material precursor solution for light emitting devices was baked at 150 ° C. for 1 hour to obtain LED device A-1 having a sealing layer having a thickness of 0.9 μm.

(Example 2: Production of LED device A-2)
The same as in Example 1, except that the stirring time before aging at the time of preparing the first polysiloxane solution and the stirring time before aging at the time of preparing the second polysiloxane solution were each 6 hours. A second polysiloxane solution and a second polysiloxane solution were prepared. The mass average molecular weight of the first polysiloxane was 3000, and the average molecular weight of the second polysiloxane was 3000. Then, the said 1st polysiloxane solution and the said 2nd polysiloxane solution are mixed, and the 1st polysiloxane: 2nd polysiloxane is the sealing material precursor for light-emitting devices whose mass ratio is 50:50 A body solution was obtained. Then, the sealing layer was formed like Example 1 (LED apparatus A-1), and LED apparatus A-2 was obtained.

(Comparative Example 1: Production of LED device A-3)
Example 1 except that the stirring time before aging at the time of preparing the first polysiloxane solution was 0.5 hour, and the stirring time before aging at the time of preparing the second polysiloxane solution was 4.5 hours. Similarly, a first polysiloxane solution and a second polysiloxane solution were prepared. The mass average molecular weight of the first polysiloxane was 500, and the average molecular weight of the second polysiloxane was 2000. Subsequently, the first polysiloxane solution and the second polysiloxane solution are mixed so that the mass ratio of the first polysiloxane: second polysiloxane is 20:80, thereby sealing the light emitting device. A stopping material precursor solution was obtained. Then, the sealing layer was formed like Example 1 (LED device A-1), and LED device A-3 was obtained.

(Comparative Example 2: Production of LED device A-4)
Example 1 except that the stirring time before aging at the time of preparation of the first polysiloxane solution was 7.5 hours, and the stirring time before aging at the time of preparation of the second polysiloxane solution was 4.5 hours. Similarly, a first polysiloxane solution and a second polysiloxane solution were prepared. The mass average molecular weight of the first polysiloxane was 4000, and the average molecular weight of the second polysiloxane was 2000. Subsequently, the first polysiloxane solution and the second polysiloxane solution are mixed so that the mass ratio of the first polysiloxane: second polysiloxane is 67:33, and the light emitting device sealing is performed. A stopping material precursor solution was obtained. A sealing layer was formed in the same manner as in Example 1 (LED device A-1) to obtain LED device A-4.

(Comparative Example 3: Production of LED device A-5)
Example 1 except that the stirring time before aging at the time of preparation of the first polysiloxane solution was 4.5 hours, and the stirring time before aging at the time of preparation of the second polysiloxane solution was 0.5 hours. Similarly, a first polysiloxane solution and a second polysiloxane solution were prepared. The mass average molecular weight of the first polysiloxane was 2000, and the average molecular weight of the second polysiloxane was 500. Subsequently, the first polysiloxane solution and the second polysiloxane solution are mixed so that the mass ratio of the first polysiloxane: second polysiloxane is 80:20 to seal the light emitting device. A stopping material precursor solution was obtained. A sealing layer was formed in the same manner as in Example 1 (LED device A-1) to obtain LED device A-5.

(Comparative Example 4: Production of LED device A-6)
The same as in Example 1 except that the stirring time before aging at the time of preparation of the first polysiloxane solution was 4.5 hours and the stirring time before aging at the time of preparation of the second polysiloxane solution was 7 hours. A first polysiloxane solution and a second polysiloxane solution were prepared. The mass average molecular weight of the first polysiloxane was 2000, and the average molecular weight of the second polysiloxane was 4000. Subsequently, the first polysiloxane solution and the second polysiloxane solution are mixed so that the mass ratio of the first polysiloxane: the second polysiloxane is 33:67 to seal the light emitting device. A stopping material precursor solution was obtained. A sealing layer was formed in the same manner as in Example 1 (LED device A-1) to obtain LED device A-6.

(Evaluation)
Liquid repellency of the sealing material precursor solution for light emitting devices prepared in Examples 1 and 2 and Comparative Examples 1 to 4, and the smoothness of the cured film (sealing material) of the sealing material precursor solution for light emitting devices. Evaluated. The results are shown in Table 1.

  As shown in Table 1, the mass average molecular weights of the first polysiloxane and the second polysiloxane are both 1000 to 3000, and in Examples 1 and 2 in which these were mixed at a mass ratio of 50:50, The liquid of the sealing material precursor solution for light emitting device was hardly repelled, and the smoothness of the cured film was good.

  On the other hand, when the molecular weight of either the first polysiloxane or the second polysiloxane contained in the encapsulant precursor solution for the light emitting device is less than 1000, the coating film shape is formed on the uneven portion on the surface of the LED element. Was not able to be maintained and liquid repellency occurred (Comparative Examples 1 and 3). This is because the sealing material precursor solution for a light emitting device was too low in viscosity and a film could not be formed sufficiently.

  On the other hand, when the mass average molecular weight of either one of the first polysiloxane and the second polysiloxane exceeds 3000, the viscosity of the sealing material precursor solution for the light emitting device is too high. It was difficult to remove the air bubbles that were bitten. Therefore, the sealing material precursor solution for light emitting devices did not adhere to a part of the surface of the LED element (Comparative Examples 2 and 4). Moreover, when the sealing material precursor solution for light emitting devices was sprayed, the droplets became too large, and the cured film was not sufficiently smooth.

[LED Device Manufacturing Method (LED Devices B-1 to B-12)]
LED devices B-1 to B-12 were produced by the following method. These LED devices have a configuration having an LED element 10 and a sealing layer (wavelength conversion type sealing layer) 6 shown in FIG.

(Example 3: Production of LED device B-1)
17.0 g of methyltrimethoxysilane, 19.0 g of tetramethoxysilane, 20.0 g of methanol, and 20.0 g of acetone were mixed and stirred. 27.3 g of water and 2.3 μL of 60% nitric acid were added to the mixture, and the mixture was further stirred for 4.5 hours. Thereafter, it was aged at 26 ° C. for 2 days. The resulting composition was diluted with methanol so that the polysiloxane solid content was 10%. A first polysiloxane solution having a polymerization molar ratio of trifunctional monomethylsilane compound: tetrafunctional silane compound of 50:50, a mass average molecular weight of 2000, and a pH of 4 was obtained.

  Subsequently, 22.5 g of dimethoxydimethylsilane, 85.1 g of methyltrimethoxysilane, 28.5 g of tetramethoxysilane, 80.0 g of methanol, and 80.0 g of acetone were mixed and stirred. 109.2 g of water and 9.2 μL of 60% nitric acid were added to the mixture, and the mixture was further stirred for 4.5 hours. Thereafter, it was aged at 26 ° C. for 2 days. The resulting composition was diluted with methanol so that the polysiloxane solid content was 10%. The bifunctional dimethylsilane compound: the trifunctional monomethylsilane compound: the tetrafunctional silane compound has a polymerization molar ratio of 18.75: 62.5: 18.75, a mass average molecular weight of 2000, and a pH of 4. A polysiloxane solution was obtained.

  Subsequently, the entire amounts of the first polysiloxane solution and the second polysiloxane solution were mixed and stirred with a stirrer for 30 minutes. Thereby, the sealing material precursor solution for light emitting devices whose mass ratio of the first polysiloxane: second polysiloxane is 20:80 was obtained.

1 g of the aforementioned phosphor particles, 0.05 g of MK-100 (synthetic mica, manufactured by Co-op Chemical), RX300 (average particle size of primary particles: 7 nm, specific surface area: 300 m ² / g, manufactured by Nippon Aerosil Co., Ltd.) 05 g and 1.5 g of propylene glycol were mixed to prepare a phosphor dispersion.

  On the other hand, one blue LED chip (cuboid: 200 μm × 300 μm × 100 μm) is flip-chip mounted at the center of the flat package shown in FIG. 2A, and a glass substrate (200 μm × 300 μm) is mounted on the LED chip. × 500 μm). Thereafter, the phosphor dispersion liquid was spray-coated on a glass substrate. Then, it was made to dry at 50 degreeC for 1 hour, and the fluorescent substance particle was arrange | positioned on the LED element. The thickness of the coating film after drying of the phosphor particle dispersion was 30 μm.

  Subsequently, the above-described sealing material precursor solution for a light emitting device is sprayed (TS-MSP-400, manufactured by Taitec Solutions Co., Ltd.) on the glass substrate of the LED element on which the phosphor particles are arranged, and on the LED chip. It applied so that a side surface and a mounting part might be covered. Then, the sealing material precursor solution for light emitting devices was baked at 150 ° C. for 1 hour to obtain LED device B-1 having a sealing layer (wavelength conversion type sealing layer) having a thickness of 20 μm.

(Example 4: Production of LED device B-2)
In the preparation of the second polysiloxane solution, 45.1 g of dimethoxydimethylsilane, 59.6 g of methyltrimethoxysilane, 28.5 g of tetramethoxysilane, 80.0 g of methanol, and 80.0 g of acetone were mixed and stirred. LED device B-2 was produced in the same manner as in Example 3 except that 109.2 g of water and 9.2 μL of 60% nitric acid were added to the mixed solution, and the mixture was further stirred for 4.5 hours. The polymerization molar ratio of bifunctional dimethylsilane compound: trifunctional monomethylsilane compound: tetrafunctional silane compound of the obtained second polysiloxane was 37.5: 43.8: 18.7, and the mass average molecular weight was 2000. It was. In addition, the first polysiloxane: second polysiloxane contained in the light emitting device sealing material precursor solution had a mass ratio of 20:80.

(Example 5: Production of LED device B-3)
In the preparation of the second polysiloxane solution, 12.0 g of dimethoxydimethylsilane, 10.2 g of methyltrimethoxysilane, 11.4 g of tetramethoxysilane, 20.0 g of methanol, and 20.0 g of acetone were mixed and stirred. LED device B-3 was produced in the same manner as in Example 3 except that 27.3 g of water and 2.3 μL of 60% nitric acid were added to the mixed solution, and the mixture was further stirred for 4.5 hours. The polymerization molar ratio of bifunctional dimethylsilane compound: trifunctional monomethylsilane compound: tetrafunctional silane compound of the obtained second polysiloxane was 40:30:40, and the mass average molecular weight was 2000. The first polysiloxane: second polysiloxane contained in the light emitting device sealing material precursor solution was 50:50 in mass ratio.

(Example 6: Production of LED device B-4)
In preparing the first polysiloxane solution, 6.8 g of methyltrimethoxysilane, 30.4 g of tetramethoxysilane, 20.0 g of methanol, and 20.0 g of acetone were mixed and stirred. 27.3 g of water and 2.3 μL of 60% nitric acid were added to the mixture, and the mixture was further stirred for 4.5 hours. The polymerization ratio of trifunctional monomethylsilane compound: tetrafunctional silane compound of the obtained first polysiloxane was 20:80, and the mass average molecular weight was 2000.

  Subsequently, in the preparation of the second polysiloxane solution, 3.8 g of dimethoxydimethylsilane, 1.7 g of methyltrimethoxysilane, 2.9 g of tetramethoxysilane, 5.0 g of methanol, and 5.0 g of acetone were mixed and stirred. LED device B-4 was produced in the same manner as in Example 3 except that 6.8 g of water and 0.6 μL of 60% nitric acid were added to the mixed solution, and the mixture was further stirred for 4.5 hours. The polymerization molar ratio of bifunctional dimethylsilane compound: trifunctional monomethylsilane compound: tetrafunctional silane compound of the obtained second polysiloxane was 50:20:30, and the mass average molecular weight was 2000. The first polysiloxane: second polysiloxane contained in the light emitting device sealing material precursor solution was 80:20 in mass ratio.

(Example 7: Production of LED device B-5)
In the preparation of the first polysiloxane solution, 10.2 g of methyltrimethoxysilane, 26.6 g of tetramethoxysilane, 20.0 g of methanol, and 20.0 g of acetone were mixed and stirred. 27.3 g of water and 2.3 μL of 60% nitric acid were added to the mixture, and the mixture was further stirred for 4.5 hours. The polymerization ratio of trifunctional monomethylsilane compound: tetrafunctional silane compound of the obtained first polysiloxane was 30:70, and the mass average molecular weight was 2000.

  Subsequently, in the preparation of the second polysiloxane solution, 3.8 g of dimethoxydimethylsilane, 2.6 g of methyltrimethoxysilane, 1.9 g of tetramethoxysilane, 5.0 g of methanol, and 5.0 g of acetone were mixed and stirred. . LED device B-5 was produced in the same manner as in Example 3 except that 6.8 g of water and 0.6 μL of 60% nitric acid were added to the mixed solution, and the mixture was further stirred for 4.5 hours. The polymerization molar ratio of bifunctional dimethylsilane compound: trifunctional monomethylsilane compound: tetrafunctional silane compound of the obtained second polysiloxane was 50:30:20, and the mass average molecular weight was 2000. The first polysiloxane: second polysiloxane contained in the light emitting device sealing material precursor solution was 80:20 in mass ratio.

(Comparative Example 5: Production of LED device B-6)
In the preparation of the first polysiloxane solution, 10.2 g of methyltrimethoxysilane, 26.6 g of tetramethoxysilane, 20.0 g of methanol, and 20.0 g of acetone were mixed and stirred. 27.3 g of water and 2.3 μL of 60% nitric acid were added to the mixture, and the mixture was further stirred for 4.5 hours. The polymerization ratio of trifunctional monomethylsilane compound: tetrafunctional silane compound of the obtained first polysiloxane was 30:70, and the mass average molecular weight was 2000.

  On the other hand, the second polysiloxane solution was not prepared. And LED apparatus B-6 was produced like Example 3 except having made the sealing material precursor solution for light emitting devices into only the 1st polysiloxane solution (the 2nd polysiloxane solution was not added). did.

(Comparative Example 6: Production of LED device B-7)
LED device B-7 was produced in the same manner as in Example 3, except that only the first polysiloxane solution was used as the sealing material precursor solution for the light emitting device (no second polysiloxane solution was added).

(Comparative Example 7: Production of LED device B-8)
In preparing the first polysiloxane solution, 23.8 g of methyltrimethoxysilane, 11.4 g of tetramethoxysilane, 20.0 g of methanol, and 20.0 g of acetone were mixed and stirred. 27.3 g of water and 2.3 μL of 60% nitric acid were added to the mixture, and the mixture was further stirred for 4.5 hours. The polymerization ratio of trifunctional monomethylsilane compound: tetrafunctional silane compound of the obtained first polysiloxane was 70:30, and the mass average molecular weight was 2000.

  On the other hand, the second polysiloxane solution was not prepared. And LED apparatus B-8 was produced like Example 3 except the sealing material precursor solution for light emitting devices only the 1st polysiloxane solution (it did not add the 2nd polysiloxane solution).

(Comparative Example 8: Production of LED device B-9)
In the preparation of the second polysiloxane solution, 15.0 g of dimethoxydimethylsilane, 4.9 g of methyltrimethoxysilane, 2.7 g of tetramethoxysilane, 14.3 g of methanol, and 14.3 g of acetone were mixed and stirred. 19.5 g of water and 1.6 μL of 60% nitric acid were added to the mixture, and the mixture was further stirred for 4.5 hours. The polymerization molar ratio of bifunctional dimethylsilane compound: trifunctional monomethylsilane compound: tetrafunctional silane compound of the obtained second polysiloxane was 70:20:10, and the mass average molecular weight was 2000.

  On the other hand, the first polysiloxane solution was not prepared. And LED device B-9 was produced like Example 3 except the sealing material precursor solution for light emitting devices only the 2nd polysiloxane solution (the 1st polysiloxane solution was not added).

(Comparative Example 9: Production of LED device B-10)
In the preparation of the second polysiloxane solution, 15.0 g of dimethoxydimethylsilane, 34.1 g of methyltrimethoxysilane, 38.1 g of tetramethoxysilane, 50.0 g of methanol, and 50.0 g of acetone were mixed and stirred. To the mixture, 68.3 g of water and 5.8 μL of 60% nitric acid were added and further stirred for 4.5 hours. The polymerization molar ratio of the bifunctional dimethylsilane compound: trifunctional monomethylsilane compound: tetrafunctional silane compound of the obtained second polysiloxane was 20:40:40, and the mass average molecular weight was 2000.

  An LED device B-10 was obtained in the same manner as in Example 3 except that the sealing material precursor solution for light emitting device was only the second polysiloxane solution (no first polysiloxane solution was added).

(Comparative Example 10: Production of LED device B-11)
In the preparation of the second polysiloxane solution, 15.0 g of dimethoxydimethylsilane, 34.1 g of methyltrimethoxysilane, 133.2 g of tetramethoxysilane, 100.0 g of methanol, and 100.0 g of acetone were mixed and stirred. To the mixture, 136.5 g of water and 11.5 μL of 60% nitric acid were added, and the mixture was further stirred for 4.5 hours. The polymerization molar ratio of the bifunctional dimethylsilane compound: trifunctional monomethylsilane compound: tetrafunctional silane compound of the obtained second polysiloxane was 10:20:70, and the mass average molecular weight was 2000.

  An LED device B-11 was obtained in the same manner as in Example 3 except that the sealing material precursor solution for the light emitting device was only the second polysiloxane solution (the first polysiloxane was not added).

(Evaluation)
D ⁿ component contained in Examples 3-7, and the cured product of the light emitting device for sealing material precursor solution prepared in Comparative Example 5 to 10, T ⁿ components, and determine the ratio of Q ⁿ components. Further, the silicon content of the cured product was determined. Moreover, about the LED device produced by each Example and the comparative example, crack tolerance, adhesiveness, and sulfuration tolerance were evaluated. The results are shown in Table 2.

  As shown in Table 2, the cured product (light-emitting device sealing material) of the light-emitting device sealing material precursor solution made only of the first polysiloxane has sufficient crack resistance and sulfide under severe test conditions. It was difficult to obtain resistance (Comparative Examples 5 to 7).

  Moreover, in the hardened | cured material (sealing material for light-emitting devices) of the sealing material precursor solution for light-emitting devices which consists only of 2nd polysiloxane, only adhesiveness and LED element (light-emitting device) have insufficient adhesiveness. (Comparative Example 8 to Comparative Example 10). When the bifunctional component is present, the adhesion at the interface with the LED element (light emitting element) tends to be lowered. In addition, when a bifunctional component is included, a dense film is hardly formed. For this reason, it is presumed that the invasion of the sulfide gas easily occurs from the gap between the sealing layer and the LED element (light emitting element), and the resistance to the sulfide gas is low.

  On the other hand, the LED device produced using the sealing material precursor solution for light emitting devices containing the mixture of 20-80 mass parts of 1st polysiloxane and 20-80 mass parts of 2nd polysiloxane, and a solvent. In Examples 3 to 7, the crack resistance of the sealing layer was high, and the adhesion between the sealing layer and the LED element was also high. Furthermore, the sulfur resistance of the LED device was also high.

  The reason is guessed as follows. The cured products of the first polysiloxane and the second polysiloxane are each distributed in clusters in the sealing layer. And the adhesiveness of the whole sealing layer increased because the hardened | cured material of the 1st polysiloxane containing comparatively many tetrafunctional components closely_contact | adhered with an LED element (light emitting element).

  Also, the second polysiloxane is less reactive than the first polysiloxane; it cures to fill voids created by cure shrinkage of the first polysiloxane. Therefore, cracks were not generated in the sealing layer, and the resistance to sulfurization was increased.

[LED Device Manufacturing Method (LED Devices B-12 to B-15)]
LED devices B-12 to B-15 were produced by the following method. These LED devices are configured to have the LED element 10 and the sealing layer 6 (wavelength conversion type sealing layer) shown in FIG.

(Example 8: Production of LED device B-12)
An LED device was prepared in the same manner as the LED device B-3 except that the amount of MK-100 (synthetic mica, manufactured by Co-op Chemical Co., Ltd.) was 0.02 g when preparing the phosphor dispersion liquid. B-12 was obtained. When the sealing layer was formed under these conditions, the thickness of the coating film after drying the phosphor particle dispersion was 8 μm, and the thickness of the obtained sealing layer was 10 μm.

(Example 9: Production of LED device B-13)
An LED device was prepared in the same manner as the LED device B-3 except that the amount of MK-100 (synthetic mica, manufactured by Co-op Chemical Co., Ltd.) was changed to 0.45 g when adjusting the phosphor dispersion liquid. B-12 was obtained. When the sealing layer was formed under these conditions, the thickness of the coating film after drying the phosphor particle dispersion was 200 μm, and the thickness of the obtained sealing layer was 450 μm.

(Example 10: Production of LED device B-14)
An LED device was prepared in the same manner as the LED device B-3 except that the amount of MK-100 (synthetic mica, manufactured by Co-op Chemical Co., Ltd.) was 0.50 g when adjusting the phosphor dispersion liquid. B-14 was obtained. When the sealing layer was formed under these conditions, the thickness of the coating film after drying the phosphor particle dispersion was 250 μm, and the thickness of the obtained sealing layer was 500 μm.

(Example 11: Production of LED device B-15)
An LED device was prepared in the same manner as the LED device B-3 except that the amount of MK-100 (synthetic mica, manufactured by Co-op Chemical Co., Ltd.) was 0.01 g when adjusting the phosphor dispersion liquid. B-15 was obtained. When the sealing layer was formed under these conditions, the thickness of the coating film after drying the phosphor particle dispersion was 5 μm, and the thickness of the obtained sealing layer was 5 μm.

(Evaluation)
About the LED device produced in Example 5 and 8-11, crack tolerance, adhesiveness, and chromaticity dispersion | variation were evaluated. The results are shown in Table 3.

  As shown in Table 3, in Examples 5, 8 and 9 where the thickness of the sealing layer is 10 μm or more and less than 500 μm, the sealing layer has high adhesion and sulfidation resistance, and the emission color of the LED device has chromaticity variation. It was hardly seen.

  On the other hand, in Example 10 where the thickness of the sealing layer is 500 μm, there is an optical path difference until light from the light source (that is, the LED chip 3) passes through the sealing layer 6 near the center and the periphery of the LED device. growing. Therefore, a difference is easily generated in the number of excited phosphor particles near the center and the outer periphery of the LED device. As a result, the chromaticity changes near the center and the periphery of the LED device; it is assumed that the chromaticity variation is slightly increased.

  Further, in Example 11 in which the film thickness of the sealing layer was 5 μm, the sulfidation resistance and the adhesiveness were somewhat lowered, and chromaticity variation occurred in part. This is presumed that chromaticity variation occurred because the phosphor particles were peeled off because the thickness was not sufficient to hold phosphor particles having a particle diameter of 10 to 20 μm. Moreover, since the phosphor particles were peeled off, voids were generated in the sealing layer, and the resistance to sulfuration was slightly reduced.

[LED Device Manufacturing Method (LED Devices A-7 to A-11)]
LED devices A-7 to A-11 were produced by the following method. These LED devices are configured to include the LED element 10 shown in FIG. 2C, the sealing layer 7, and the phosphor-containing resin layer 8.

(Example 12: Production of LED device A-7)
A sealing layer was formed on the LED element in the same manner as in the LED device A-1, except that the thickness of the sealing layer was 0.5 μm.

  Thereafter, 10% by mass of the phosphor prepared by the above-described method was dispersed in a silicone resin (OE6630, manufactured by Toray Dow Corning). The phosphor dispersion was evacuated for 10 minutes and degassed. Subsequently, it was fully poured into the recesses of the package in which the sealing layer was formed. And it heated at 100 degreeC for 30 minutes. Furthermore, the resin was cured by heating at 150 ° C. for 1 hour to obtain a phosphor-containing resin layer. The thickness of the obtained phosphor-containing resin layer 8 was 2.5 mm.

(Example 13: Production of LED device A-8)
A sealing layer was formed on the LED element in the same manner as in the LED device A-1, except that the thickness of the sealing layer was 1.5 μm. Thereafter, a phosphor-containing resin layer was produced in the same manner as in Example 12.

(Example 14: Production of LED device A-9)
A sealing layer was formed on the LED element in the same manner as in the LED device A-1, except that the thickness of the sealing layer was 15 μm. Thereafter, a phosphor-containing resin layer was produced in the same manner as in Example 12.

(Example 15: Production of LED device A-10)
A sealing layer was formed on the LED element in the same manner as in the LED device A-1, except that the thickness of the sealing layer was 0.3 μm. Thereafter, a phosphor-containing resin layer was produced in the same manner as in Example 12.

(Example 16: Production of LED device A-11)
A sealing layer was formed on the LED element in the same manner as in the LED device A-1, except that the thickness of the sealing layer was 20 μm. Thereafter, a phosphor-containing resin layer was produced in the same manner as in Example 12.

(Evaluation)
About the LED device produced in Examples 12-16, the sulfidation tolerance and the crack tolerance were evaluated. The results are shown in Table 4.

  As shown in Table 4, in Examples 12 to 14 in which the sealing layer had a thickness of 0.5 μm or more and 15 μm or less, adhesion and sulfidation resistance were high. On the other hand, in Example 15 in which the film thickness was 0.3 μm, the gas barrier property was slightly low because the film thickness was thin. Further, in Example 16 in which the thickness of the sealing layer 7 was 20 μm, some cracks were generated, and corrosion due to sulfide gas or the like was liable to occur.

[LED Device Manufacturing Method (LED Devices B-16 and B-17)]
LED devices B-16 and B-17 were produced by the following method. These LED devices have a configuration having an LED element 10 and a sealing layer (wavelength conversion type sealing layer) 6 shown in FIG.

(Example 17: Production of LED device B-16)
An LED device was produced in the same manner as LED device B-5, except that the encapsulant precursor solution for light emitting device was cured at 80 ° C. for 1 hour, to obtain LED device B-16.

(Example 18: Production of LED device B-17)
An LED device was produced in the same manner as LED device B-5, except that the encapsulant precursor solution for light emitting device was cured at 100 ° C. for 1 hour, to obtain LED device B-17.

(Evaluation)
The light resistance of the LED devices produced in Examples 7, 17, and 18 was evaluated. The results are shown in Table 5.

  As shown in Table 5, the evaluation results of light resistance were good in Example 18 and Example 5 cured at 100 ° C. or higher for the light emitting device sealing material precursor solution. In particular, in Example 5 in which the precursor solution was cured at 150 ° C. or higher, photodegradation of the sealing layer was difficult to occur.

  On the other hand, in Example 17 in which the sealing material precursor solution for a light-emitting device was cured by heating at 80 ° C., water and the like generated during the dehydration condensation of the silane compound could not be sufficiently removed; Presumed to have declined.

(Reference Example: Production of LED devices C-1 to C-17)
The LED element which has the package 1 (LED board | substrate) which has a recessed part was prepared. Specifically, an LED in which one blue LED chip (cuboid: 200 μm × 300 μm × 100 μm) is flip-chip mounted in the center of a housing portion of a circular package (opening diameter 3 mm, bottom diameter 2 mm, wall surface angle 60 °) A device was prepared. The phosphor dispersion liquid is applied onto the LED chip element in the same manner as the LED devices B-1 to B-17 described above, and a sealing material precursor solution for a light emitting device is further applied to form a sealing layer. LED devices C-1 to C-17 were obtained. These LED devices have a configuration having an LED element 10 and a sealing layer (wavelength conversion type sealing layer) 6 shown in FIG.

  When the obtained LED devices C-1 to C-17 were tested in the same manner as the LED devices B-1 to B-17, the same results were obtained.

  The cured film of the light emitting device sealing material precursor solution of the present invention is free from cracks, has high adhesion to the light emitting element, and is dense. Therefore, the LED device in which the LED element is sealed with the cured film has a very high gas barrier property. Therefore, the LED device can be applied to both indoor and outdoor lighting devices.

DESCRIPTION OF SYMBOLS 1 LED substrate 2 Metal part 3 LED chip 4 Projection electrode 5 Glass substrate 6 (wavelength conversion type) sealing layer 7 Sealing layer 8 Phosphor-containing resin layer 10 LED element 100 LED device

Claims (8)

A first polysiloxane having a mass average molecular weight of 1000 to 3000 obtained by copolymerizing a trifunctional monomethylsilane compound and a tetrafunctional silane compound;
A second polysiloxane having a mass average molecular weight of 1000 to 3000 obtained by copolymerizing a bifunctional dimethylsilane compound, a trifunctional monomethylsilane compound, and a tetrafunctional silane compound;
A solvent,
Including
The content ratio of the first polysiloxane with respect to 100 parts by mass of the total amount of the first polysiloxane and the second polysiloxane is 20 to 80 parts by mass, and the content ratio of the second polysiloxane is 20 to 80 parts by mass. A sealing material precursor solution for a light emitting device.   2. The light emitting device sealing according to claim 1, wherein a silicon content of a cured reaction product obtained by curing reaction of the first polysiloxane and the second polysiloxane in the content ratio is 20% by mass or more. Material precursor solution. A sealing material for a light emitting device for sealing a light emitting element obtained by curing the sealing material precursor solution for a light emitting device according to claim 1 or 2,
The ratio of the number of moles of silicon atoms bonded with four oxygen atoms to the total number of moles of silicon atoms, as measured by solid Si-nuclear magnetic resonance spectrum, is 25 to 60%,
The ratio of the number of moles of silicon atoms having only three oxygen atoms bonded to the total number of moles of silicon atoms, as measured by solid-state Si-nuclear magnetic resonance spectrum, is 25 to 60%,
The ratio of the number of moles of silicon atoms in which only two oxygen atoms are bonded to the total number of moles of silicon atoms, as measured by solid Si-nuclear magnetic resonance spectrum, is 5% or more and less than 30%. .   The sealing material for light emitting devices of Claim 3 which further contains fluorescent substance particles.   The sealing material for light emitting devices of Claim 3 or 4 whose said light emitting element is an LED element. An LED device comprising: an LED element; a sealing layer covering the LED element; and a phosphor-containing resin layer containing a resin and phosphor particles formed on the sealing layer,
The sealing layer comprises a cured product of the light emitting device sealing material precursor solution according to claim 1,
The LED device whose thickness of the said sealing layer is 0.5 micrometer or more and 15 micrometers or less. An LED device having an LED element and a sealing layer that covers the LED element and includes phosphor particles,
The sealing layer includes a cured product of the sealing material precursor solution for a light emitting device according to claim 1 or 2,
The LED device whose thickness of the said sealing layer is 10 micrometers or more and less than 500 micrometers. A step of preparing an LED element;
Applying the sealing material precursor solution for a light emitting device according to claim 1 or 2 on the LED element;
Curing the light emitting device sealing material precursor solution at 100 ° C. or higher;
The manufacturing method of the LED device containing this.

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