JP2020105475A - Curable composition for ultraviolet light emitting device, component for ultraviolet light emitting device, and ultraviolet light emitting device - Google Patents

Abstract

To provide a curable composition for an ultraviolet light emitting device which can achieve high output and high reliability; a cured product; a component for an ultraviolet light emitting device; and an ultraviolet light emitting device.SOLUTION: The curable composition for the ultraviolet light emitting device comprises cyclic silanol (A1) represented by the following formula (1), and a dehydration condensate (A2), where in the formula (1), R is each independently a fluorine atom, an aryl group, a vinyl group, an allyl group, a linear or branched alkyl group having 1 to 4 carbon atoms substituted with fluorine, or an unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms; and n is an integer of 2 to 10.SELECTED DRAWING: None

Description

The present invention relates to a curable composition for ultraviolet light emission measures, a component for ultraviolet light emission measures, and an ultraviolet light emission device.

BACKGROUND ART A light emitting device capable of emitting light in the ultraviolet region has been attracting attention as an ultraviolet light source with low power consumption and long life, which is an alternative to a mercury lamp, and has been applied in various applications such as inspection measurement, ultraviolet curing and sterilization. A light emitting device having this light emitting element is strongly desired to have high output and long-term reliability.

Here, one of the widely used methods for increasing the output is a method using a hemispherical lens made of an ultraviolet-transparent material. In this method, an ultraviolet-transparent material is arranged on the light extraction surface side of the light emitting element, and the light emitted from the light extraction surface is extracted to the outside through a hemispherical lens. Generally, in the extraction of light from the inside of the hemispherical lens to the outside of the lens (air), the angle of incidence on the lens-air interface can be made small, so that total reflection can be suppressed and a large amount of light can be extracted to the outside. .. In this method, in order to reduce the total reflection at the light-emitting element-air interface, a refractive index relaxing substance is filled in the space between the light-emitting element chip and the hemispherical lens, if necessary. According to this method, the total reflection at the light emitting element-air interface described above is reduced, and more light is incident on the hemispherical lens. Therefore, by combining the hemispherical lens and this refractive index relaxing substance (there may be a hemispherical lens structure in some cases), it becomes possible to more efficiently extract the light from the light emitting element.

As the refractive index relaxing substance, for example, a transparent fluororesin (see Patent Document 1) and a silicone resin are known (see Patent Document 2).

JP, 2016-111085, A Japanese Patent Publication No. 2017-521872

However, at present, there is no ultraviolet light emitting device having a lens, particularly, an ultraviolet light emitting device having an emission peak wavelength in the range of 210 nm or more and less than 300 nm, which has satisfactory output and reliability. Hereinafter, a light emitting device having an emission peak wavelength in the range of 210 nm or more and less than 300 nm is also simply referred to as "deep ultraviolet light emitting device".

For example, in the light emitting device described in Patent Document 1, the adhesiveness of the refractive index relaxation material is insufficient, and when the light is turned on at a current value of 350 mA for more than 100 hours, the light output is reduced. Furthermore, in the light-emitting device described in Patent Document 2, the refractive index relaxation substance deteriorates with time, so that a decrease in output after 100 hours has been observed.

Therefore, an object of the present invention is to provide a curable composition for an ultraviolet light emitting device, a cured product, a component for an ultraviolet light emitting device, and an ultraviolet light emitting device, which can realize high output and high reliability.

The present inventors diligently studied to solve the above problems. As a result, they have found that the above problems can be solved by using a curable composition containing a silicon compound having a specific structure and a dehydration condensation product thereof as a material for forming an ultraviolet light emitting device, and have completed the present invention. The curable composition has a function as a material for relaxing the refractive index, and can bond the bottom surface of the ultraviolet transparent material and the light extraction surface of the deep ultraviolet light emitting device, respectively.

That is, the present invention is as follows.
[1]
A curable composition for an ultraviolet light emitting device, which comprises a cyclic silanol (A1) represented by the following formula (1) and a dehydration condensation product (A2) thereof.

(In the formula (1), each R is independently a fluorine atom, an aryl group, a vinyl group, an allyl group, a linear or branched alkyl group having 1 to 4 carbon atoms substituted with fluorine, or a non- It is a substituted linear or branched alkyl group having 1 to 4 carbon atoms, and n is an integer of 2 to 10.)
[2]
The cyclic silanol (A1) represented by the formula (1) and its dehydrated condensate (A2) are the cyclic silanol (A10) represented by the following formula (10) and its dehydrated condensate (A20). The curable composition for an ultraviolet light emitting device according to [1].

(In the formula (10), R has the same meaning as R in the formula (1).)

[3]
The cyclic silanol (A10) is a cyclic silanol (B1) to (B4) represented by the following formulas (2) to (5), and the cyclic silanol (B1) to (B4) relative to the total amount of the cyclic silanol (B1) to (B4). The curable composition for an ultraviolet light emitting device according to the above [2], wherein 0<b≦20 is satisfied, where b2 is the proportion (mol %) of B2).

(In the formulas (2) to (5), R has the same meaning as R in the formula (1).)
[4]
When the ratio (mol%) of the cyclic silanol (B1) to the total amount of the cyclic silanols (B1) to (B4) is set to a, 0<a≦60 is satisfied, the curing for the ultraviolet light emitting device according to the above [3]. Sex composition.
[5]
The curable composition for an ultraviolet light emitting device according to any one of the above [1] to [4], which has a haze of 5% or less in the form of a cured product having a thickness of 3 μm.
[6]
In the peak of the chromatogram obtained by the measurement of gel permeation chromatography, the area of the dehydrated condensate (A2) is 0% with respect to the total area of the cyclic silanol (A1) and the dehydrated condensate (A2). The curable composition for an ultraviolet light emitting device according to any one of the above [1] to [5], which is 50% or less in excess.
[7]
The curable composition for an ultraviolet light emitting device according to any one of the above [1] to [6], wherein the content of the transition metal is less than 1 mass ppm.
[8]
The curable composition for an ultraviolet light emitting device according to any one of the above [1] to [7], which contains a solvent.
[9]
The curable composition for an ultraviolet light emitting device according to any one of the above [1] to [8], which contains silica particles having an average particle diameter of 1 nm or more and 100 nm or less.
[10]
The curable composition for an ultraviolet light emitting device according to any one of the above [1] to [9], which comprises a silanol-modified siloxane with both terminals represented by the following general formula (6).

(In the general formula (6), R′ is each independently fluorine, an aryl group, a vinyl group, an allyl group, a linear or branched C 1 -C 4 alkyl group substituted with fluorine, Alternatively, it is an unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms, and m is an integer of 0 to 1000.)
[11]
The curable composition for an ultraviolet light emitting device according to any one of the above [1] to [10], wherein the total content of Na and V is less than 60 mass ppm.
[12]
The curable composition for a light emitting device according to any one of the above [1] to [11], which is for a deep ultraviolet light emitting device that emits deep ultraviolet light of 210 nm or more and less than 300 nm.
[13]
A cured product of the curable composition for an ultraviolet light emitting device according to any one of [1] to [12] above.
[14]
What is claimed is: 1. A component for an ultraviolet light emitting device, comprising an ultraviolet light emitting element and a refractive index relaxation material layer arranged on the light extraction surface of the ultraviolet light emitting element, wherein the refractive index relaxation material layer is the cured product of [13] above. Ultraviolet light emitting device components including.
[15]
The component for an ultraviolet light emitting device according to the above [14], wherein the light extraction surface of the ultraviolet light emitting element is formed of an aluminum nitride single crystal.
[16]
The component for an ultraviolet light emitting device according to the above [14] or [15], wherein the ultraviolet light emitting device is a deep ultraviolet light emitting device that emits deep ultraviolet light of 210 nm or more and less than 300 nm.
[17]
A component for a light emitting device having an ultraviolet-transmissive member and a refractive index relaxation layer arranged on an incident surface of the ultraviolet transparent member, wherein the refractive index relaxation material layer contains the cured product according to the above [13]. Ultraviolet light emitting device parts.
[18]
The component for an ultraviolet light emitting device according to the above [17], wherein the ultraviolet transparent member is a lens or a plate-shaped member.
[19]
The component for an ultraviolet light emitting device according to the above [18], wherein the lens is a hemispherical lens.
[20]
The component for an ultraviolet light emitting device according to any one of the above [17] to [19], wherein the material for forming the ultraviolet transparent member is a refractive index relaxing substance, quartz or sapphire.
[21]
The component for an ultraviolet light emitting device according to any one of the above [17] to [20], wherein the ultraviolet light transmissive member is a deep ultraviolet light transmissive member capable of transmitting deep ultraviolet light of 210 nm or more and less than 300 nm.
[22]
An ultraviolet light transmitting member, an ultraviolet light emitting element, and a refractive index relaxing substance layer disposed between an incident surface of the ultraviolet transparent member and a light extraction surface of the ultraviolet light emitting device, and the refractive index relaxing substance layer. Is an ultraviolet light emitting device containing the cured product according to [13].
[23]
The ultraviolet light emitting device according to the above [22], wherein the light output ratio after lighting for 100 hours is 0.9 or more under the conditions of an ambient temperature of 25° C. and a current value of 350 mA.
[24]
The ultraviolet light transmissive member is a deep ultraviolet light transmissive member capable of transmitting deep ultraviolet light of 210 nm or more and less than 300 nm, and the ultraviolet light emitting device is a deep ultraviolet light emitting device that emits deep ultraviolet light of 210 nm or more and less than 300 nm. The ultraviolet light emitting device according to the above [22] or [23].

According to the present invention, it is possible to provide a curable composition for an ultraviolet light emitting device, a cured product, an ultraviolet light emitting device component, and an ultraviolet light emitting device, which can realize high output and high reliability.

It is a schematic cross section which shows an example of the ultraviolet light-emitting device of this invention. It is a figure which shows the typical thing of the lens shape in this invention. It is a schematic cross section which shows an example of the ultraviolet light emitting element in this invention. It is a schematic cross section which shows the lens used in Example 18A. It is a schematic cross section which shows the lens used in Example 19A. It is a schematic cross section which shows the lens used in Example 20A. FIG. 5 is a diagram showing a ¹ H-NMR spectrum used when calculating a stereoisomer ratio of a silanol composition obtained in Example 10. FIG. 7 is a diagram showing a ¹ H-NMR spectrum used when calculating a stereoisomer ratio of the silanol composition obtained in Example 16.

Hereinafter, modes for carrying out the present invention (hereinafter, also referred to as “the present embodiment”) will be described in detail. It should be noted that the present invention is not limited to this embodiment, and various modifications can be carried out within the scope of the gist thereof.

(Curable composition for ultraviolet light emitting device)
The curable composition for an ultraviolet light emitting device of the present embodiment (hereinafter, also simply referred to as “curable composition” or “silanol composition”) is a cyclic silanol (A1) represented by the following formula (1) and its composition. The dehydration condensate (A2) is included. The curable composition contains a cyclic silanol (A1) represented by the following formula (1) and its dehydrated condensate (A2), so that the curable composition has high output and reliability when used as a material for forming an ultraviolet light emitting device. realizable. Therefore, the curable composition of the present embodiment is preferably for a deep ultraviolet light emitting device that emits deep ultraviolet light of 210 nm or more and less than 300 nm.

In formula (1), each R is independently a fluorine atom, an aryl group, a vinyl group, an allyl group, a linear or branched alkyl group having 1 to 4 carbon atoms substituted with fluorine, or an unsubstituted group. Is a linear or branched alkyl group having 1 to 4 carbon atoms. n is an integer of 2 to 10.

In formula (1), each R is independently a fluorine-substituted linear or branched alkyl group having 1 to 4 carbon atoms, or an unsubstituted linear or branched carbon atom having 1 to 4 carbon atoms. It is preferably a C4 alkyl group, more preferably an unsubstituted linear or branched C1-4 alkyl group, and even more preferably a methyl group. Thereby, the curable composition tends to exhibit higher output and higher reliability.

In the formula (1), n is preferably 2 to 5, and more preferably 2 to 4. 3 is particularly preferable. As a result, the flexibility and rigidity of the main chain skeleton are balanced, so that durability tends to be exhibited by ultraviolet irradiation.

The cyclic silanol (A1) represented by the formula (1) and its dehydrated condensate (A2) are preferably the cyclic silanol (A10) represented by the formula (10) and its dehydrated condensate (A20). .. As a result, the flexibility and rigidity of the main chain skeleton are balanced, so that durability tends to be exhibited by ultraviolet irradiation.

Further, the silanol composition of the present embodiment preferably has a haze of 5% or less at a thickness of 3 μm. This tends to improve the optical transparency.

In the formula (10), R has the same meaning as R in the formula (1).

The silanol composition of the present embodiment preferably has a haze of 5% or less at a thickness of 3 μm. When the haze of the silanol composition is 5% or less, the transparency of the cured product tends to be high and the adhesive strength tends to be excellent. As a method for reducing the haze in the silanol composition to 5% or less, for example, the proportion of isomers in the cyclic silanol (A1) represented by the formula (1) is adjusted to reduce the proportion of isomers having high crystallinity. Examples include a method and a method of suppressing the amount of metal contained in the composition. The haze of the silanol composition is more preferably 2% or less, further preferably 1% or less. The haze of the silanol composition can be specifically measured by the method described in Examples.

The silanol composition of the present embodiment contains a dehydrated condensate of cyclic silanol represented by the formula (1). The dehydrated condensate of the cyclic silanol represented by the formula (1) means that at least one of the silanol groups contained in the cyclic silanol represented by the formula (1) is another cyclic group represented by the formula (1). It is a compound obtained by a reaction of forming a siloxane bond by dehydration condensation with at least one silanol group in a silanol molecule. The dehydrated condensate of cyclic silanol represented by the formula (1) can be schematically represented by the following formula (20).

In formula (20), four Rs have the same meanings as R in formula (1). And m is an integer of 2 or more. The silanol group that undergoes dehydration condensation in the cyclic silanol may be any silanol group. At this time, in the dehydration condensation product represented by the formula (20), two or more siloxane bonds may be formed between two or more molecules of the cyclic silanol structure.

Specific examples of the dehydrated condensate of the cyclic silanol represented by the formula (10) include the following compounds. However, the dehydrated condensate of cyclic silanol represented by the formula (10) is not limited to the following compounds.
The orientations of the hydroxy group (—OH) and the R group with respect to the cyclic silanol skeleton in the following compounds are not limited. Moreover, R in the following compounds is each independently ^one of R ^{1 to} R ⁴ in the formula (10). Furthermore, as the preferable groups of R in the following compounds, the same preferable groups as the R ^{1 to} R ⁴ groups can be mentioned.

The dehydrated condensate of the cyclic silanol represented by the formula (10) has a molecular weight calculated by gel permeation chromatography of preferably 500 to 1,000,000, more preferably 500 to 100,000. Yes, and more preferably 500-10,000.

In the silanol composition of the present embodiment, in the measurement of gel permeation chromatography, the area of the dehydrated condensate (A2) is relative to the total area of the cyclic silanol (A1) and the dehydrated condensate (A2), It is preferably more than 0% and 50% or less. The area of each compound obtained by the measurement of gel permeation chromatography represents the content of each compound in the silanol composition. When the area of A2 is more than 0% and 50% or less, the viscosity does not become too high when the silanol composition is produced, and the organic solvent and water are easily removed from the silanol composition containing the organic solvent and water. There is a tendency. The area of A2 is more preferably more than 0% and 40% or less, still more preferably more than 0% and 25% or less. The area of A2, that is, the content of A2 can be controlled, for example, by purification after the oxidation reaction when a hydrosilane compound is oxidized to obtain a cyclic silanol in the production of a silanol composition. The area of A1 and A2, that is, the content of A1 and A2 by gel permeation chromatography can be specifically measured by the method described in Examples.

The silanol composition of this embodiment can be prepared by, for example, oxidizing a hydrosilane compound in the presence of water or alcohol. As the hydrosilane compound, any tetra-substituted tetracyclosiloxane containing hydrogen can be used, and a commercially available product can be used. The hydrosilane compound is preferably a tetra-substituted tetracyclosiloxane represented by the following formula (8).

In the formula (8), each R is independently a fluorine, an aryl group, a vinyl group, an allyl group, a linear or branched alkyl group having 1 to 4 carbon atoms substituted with fluorine, or an unsubstituted group. Is a straight-chain or branched alkyl having 1 to 4 carbon atoms.

Specific examples of the cyclic hydrosilane compound include tetramethyltetracyclosiloxane and the like. Generally, the cyclic hydrosilane compound does not have a hydroxy or alkoxy functional group, but such functional group may be included in a certain amount before the oxidation reaction.

Examples of the method of oxidizing the hydrosilane compound include a method of using a catalyst and/or an oxidizing agent. As the catalyst, for example, a metal catalyst such as Pd, Pt and Rh can be used. These metal catalysts may be used alone or in combination of two or more. Further, these metal catalysts may be supported on a carrier such as carbon.
As the oxidant, for example, peroxides and the like can be used. Any of the peroxides can be used, and examples thereof include oxiranes such as dimethyldioxirane.
As a method of oxidizing the hydrosilane compound, it is preferable to use Pd/carbon from the viewpoint of reactivity and easy removal of the catalyst after the reaction.

Cyclic silanol prepared by oxidizing a hydrosilane compound in the presence of water or alcohol has various isomers derived from cis and trans of the hydrogen atom of the starting SiH group because of its cyclic structure. ..
The cyclic hydrosilane compound represented by the above formula (8) is obtained by hydrolysis of chlorosilane or equilibrium polymerization reaction of polymethylsiloxane, but it is difficult to control the ratio of cis and trans isomers. Therefore, various cis and trans isomers are mixed in the cyclic hydrosilane compound. The cis and trans of the cyclic hydrosilane compound in the present embodiment mean that two adjacent hydroxy groups or two adjacent R groups have the same orientation with respect to the cyclic siloxane skeleton (cis), and two adjacent hydroxy groups. Alternatively, two adjacent R groups have different orientations with respect to the cyclic siloxane skeleton (trans).

Examples of the isomers contained in the cyclic silanol produced by the above-mentioned oxidation reaction include all-cis type cyclic silanol (B1) represented by the following formula (2). In the all-cis type cyclic silanol (B1), all the hydroxy groups and the R ^{1 to} R ⁴ groups are respectively arranged in the same direction with respect to the cyclic siloxane skeleton, as shown by the formula (2).

In the formula (2), each R is independently fluorine, an aryl group, a vinyl group, an allyl group, a linear or branched alkyl group having 1 to 4 carbon atoms substituted with fluorine, or an unsubstituted group. It is a linear or branched alkyl group having 1 to 4 carbon atoms.

With the all-cis type cyclic silanol (B1) represented by the formula (2), the cyclic silanol synthesized from the cyclic hydrosilane compound by the oxidation reaction tends to become cloudy. This phenomenon is considered to be due to the crystallinity of the all-cis type cyclic silanol (B1), and is particularly remarkable during storage or when frozen at −30° C. By removing the highly crystalline cyclic silanol, it is possible to prevent the silanol from crystallizing and precipitating in the silanol composition, a highly transparent silanol composition is obtained, and a highly transparent cured product can also be obtained. it can. Further, by removing the cyclic silanol having high crystallinity, the adhesive force of the silanol composition is improved.

From the viewpoint of obtaining a highly transparent silanol composition, it is preferable to keep the ratio of the cyclic silanol (B1) small.
Examples of the method for suppressing the proportion of the cyclic silanol (B1) include a method in which a recrystallization operation and a crystal removal are combined.
More specifically, by adding a poor solvent to a good solvent solution of the product obtained by the synthesis of cyclic silanol, cyclic silanol (B1) is precipitated as crystals. By removing the precipitated cyclic silanol (B1) and concentrating the solution in the soluble portion, the ratio of the cyclic silanol (B1) in the silanol composition can be suppressed and a highly transparent silanol composition can be obtained.

When performing the recrystallization operation, the cooling temperature is preferably less than 10° C. from the viewpoint of obtaining a highly transparent silanol composition. From the viewpoint of improving the yield of cyclic silanol, the amount (volume) of the poor solvent is preferably equal to or more than 20 times the equivalent amount of the good solvent.

Examples of the good solvent include tetrahydrofuran, diethyl ether, acetone, methanol, ethanol, isopropanol, dimethylformamide, dimethyl sulfoxide, glycerin, ethylene glycol, methyl ethyl ketone, and the like. These good solvents may be used alone or in combination of two or more.
Examples of the poor solvent include toluene, chloroform, hexane, dichloromethane, xylene and the like. These poor solvents may be used alone or in combination of two or more.

Ratio of cyclic silanol (B1) is a cyclic silanol obtained by synthesis can be calculated from measuring ¹ H-NMR. Specifically, in the ¹ H-NMR measurement, hydrogen contained in R ¹ to R ⁴ radicals having cyclic silanol (B1) is a hydrogen R ¹ to R ⁴ radicals having other isomers of cyclic silanol On the other hand, it is observed at the highest magnetic field side. Therefore, the ratio of cyclic silanol (B1) is calculated from the integrated value of these hydrogens.

When a metal catalyst is used for the oxidation of the hydrosilane compound, the recrystallization operation described above causes the transition metal contained in the metal catalyst to remain in the insoluble residue. The proportion of metal can be reduced. Therefore, by the operation for removing the cyclic silanol represented by the formula (2), it is possible to reduce the coloring of the silanol due to the residual metal catalyst. From the viewpoint of increasing the light transmittance of the silanol composition, the proportion of the transition metal is preferably less than 1 mass ppm with respect to the total weight of the silanol composition. The proportion of transition metal can be specifically measured by the method described in Examples. Examples of the transition metal include palladium.

Further, when a tetrasubstituted tetracyclosiloxane represented by the formula (8) is used as a hydrosilane compound as a raw material and is oxidized, the obtained tetrahydroxytetrasubstituted tetracyclosiloxane is represented by the following formulas (2) to (5). The cyclic silanols (B1) to (B4) may be mixed and are preferably composed of the cyclic silanols (B1) to (B4).

In formulas (2) to (5), each R independently represents fluorine, an aryl group, a vinyl group, an allyl group, a fluorine-substituted linear or branched alkyl group having 1 to 4 carbon atoms, Alternatively, it is an unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms.

The cyclic silanol (A10) in the present embodiment contains the cyclic silanols (B1) to (B4) represented by the following formulas (2) to (5), and is based on the total amount of the cyclic silanols (B1) to (B4). When the ratio (mol %) of the cyclic silanol (B2) is b, 0<b≦20 is preferably satisfied. This tends to improve the optical transparency by suppressing the crystallization of the cyclic silanol.

As a method of setting the ratio b to 0<b≦20, as described above, for example, a method of combining a recrystallization operation and removal of crystals can be mentioned. When tetramethyltetracyclosiloxane is used as a raw material for the hydrosilane compound and is oxidized, when ¹ H-NMR of the resulting tetrahydroxytetramethyltetracyclosiloxane is measured, 6 types of peaks of 4 types of isomers are observed. (Here, three kinds of peaks are observed for trans-trans-cis.) Hydrogen in the R ^{1 to} R ⁴ groups is all-cis (cyclic silanol (B1)), trans-trans-cis (cyclic silanol (B3)), trans-trans-cis (cyclic silanol (B3) from the high magnetic field side. )), cis-trans-cis (cyclic silanol (B2)), all-trans (cyclic silanol (B4)), trans-trans-cis (cyclic silanol (B3)) type are observed in this order, so From the integrated value, the respective proportions of the cyclic silanols (B1) to (B4) are calculated.

Since the cyclic silanol (B2) represented by the formula (3) also has crystallinity, when a good solvent is used in the reaction solution, it is precipitated as a crystal by adding a poor solvent. Due to the cyclic silanol (B2), the synthesized cyclic silanol (A1) tends to become cloudy. This phenomenon is considered to be because the cis-trans-cis type cyclic silanol (B2) has crystallinity, and is particularly remarkable during storage or when frozen at -30°C.

From the viewpoint of obtaining a highly transparent silanol composition, the ratio of the cyclic silanol (B2) is preferably 0% to 50%, more preferably 0%, with respect to the cyclic silanol represented by the formula (1). It is -40%, more preferably 0-35%, and even more preferably 0% or more and less than 35%.

When the ratio (mol %) of the cyclic silanol (B1) to the total amount of the cyclic silanols (B1) to (B4) is a, it is preferable that 0<a≦60 is satisfied. This tends to improve the optical transparency by suppressing the crystallization of the cyclic silanol.

Examples of the method of setting the ratio b to 0<a≦60 include a method of synthesizing (B1) by a known method and mixing them.

As described above, the silanol composition of the present embodiment is a good solvent solution of a product obtained by preparing a cyclic silanol by oxidizing a hydrosilane compound in the presence of water or an alcohol and synthesizing the cyclic silanol. It is preferably produced by subjecting the solution of the soluble portion obtained by filtration to recrystallization and filtration by adding a poor solvent to the solution and concentrating the solution. In the production of the silanol composition of this embodiment, the solution of the soluble part may be optionally concentrated, and the solution of the soluble part itself may be used as the silanol composition. Moreover, since it is not necessary to remove all the solvent contained in the solution in the concentration of the solution in the soluble part, the silanol composition of the present embodiment distills off part of the solvent contained in the solution in the soluble part. It may be a crude concentrate obtained by. Furthermore, the silanol composition of the present embodiment may be obtained by concentrating the solution of the soluble part and then re-diluting it with a solvent.

As described above, one of the preferable aspects of the present embodiment is a silanol composition containing a solvent. The amount of the solvent in the silanol composition containing the solvent is not particularly limited, but is preferably 95% by mass or less, more preferably 90% by mass or less, and further preferably 85% by mass or less based on the total amount of the silanol composition. Is. The lower limit of the amount of solvent is not particularly limited, but is usually 1% by mass or more.

Examples of the solvent in the silanol composition containing the solvent include water and/or alcohol used in the reaction, a good solvent and a poor solvent used in recrystallization, and the like. The solvent is not limited to the following, specifically, water, tetrahydrofuran, diethyl ether, acetone, methanol, ethanol, isopropanol, dimethylformamide, dimethyl sulfoxide, glycerin, ethylene glycol, methyl ethyl ketone, toluene, chloroform. , Hexane, dichloromethane, xylene and the like. These solvents may be used alone or in combination of two or more.

The silanol composition of the present embodiment preferably further contains silica particles having an average particle size of 1 nm or more and 100 nm or less. When the average particle diameter of the silica particles is 1 nm or more, the abrasion resistance tends to be excellent. Further, when the particle size of the silica particles is 100 nm or less, the transparent dispersibility tends to be excellent. The average particle size of the silica particles is preferably 1 nm or more and 50 nm or less, more preferably 2 nm or more and 30 nm or less, and further preferably 5 nm or more and 20 nm or less. The average particle size of silica particles can be measured by dynamic light scattering measurement.

The silica particles having an average particle size of 1 nm or more and 100 nm or less are not particularly limited in form as long as the transparency of the silanol composition of the present embodiment can be maintained. The silica particles can be used in the form of an ordinary aqueous dispersion or in the form of being dispersed in an organic solvent, but from the viewpoint of uniformly and stably dispersing in a silanol composition, colloidal silica dispersed in an organic solvent. Is preferably used.

The organic solvent in which the silica particles are dispersed is not limited to the following. For example, methanol, isopropyl alcohol, n-butanol, ethylene glycol, xylene/butanol, ethyl cellosolve, butyl cellosolve, dimethylformamide, dimethylacetamide, methyl ethyl ketone. , Methyl isobutyl ketone, and the like.
Among these, it is preferable to select an organic solvent capable of dissolving the silanol composition, from the viewpoint of uniformly dispersing the silica particles in the silanol composition.

The colloidal silica dispersed in an organic solvent is not limited to the following, and examples thereof include methanol silica sol MA-ST, isopropyl alcohol silica sol IPA-ST, n-butanol silica sol NBA-ST, ethylene glycol silica sol EG. -ST, xylene/butanol silica sol XBA-ST, ethyl cellosolve silica sol ETC-ST, butyl cellosolve silica sol BTC-ST, dimethylformamide silica sol DBF-ST, dimethylacetamide silica sol DMAC-ST, methyl ethyl ketone silica sol MEK-ST, methyl isobutyl ketone silica sol MIBK-. Commercially available products such as ST (above, trade name, manufactured by Nissan Kagaku Co., Ltd.) can be used.

When the silanol composition of the present embodiment further contains silica particles having an average particle size of 1 nm or more and 100 nm or less, a cyclic silanol is prepared by oxidizing a hydrosilane compound in the presence of water or alcohol, as described above, After recrystallization by adding a poor solvent to a good solvent solution of the product obtained by the synthesis of cyclic silanol, and filtering, the solution of the soluble portion obtained by filtration is concentrated, and further, the average particle diameter is 1 nm or more and 100 nm. It is preferably produced by adding the following silica particles or a silica particle dispersion liquid.

The content of the silica particles in the silanol composition of the present embodiment is preferably 10 to 80% by mass, more preferably 20 to 70% by mass, based on the total amount of solids in the silanol composition. More preferably, it is 30 to 60 mass %.
When the content of the silica particles is 10% by mass or more, the resulting cured product tends to have excellent wear resistance. Further, when the content of the silica particles is 80% by mass or less, the obtained cured product tends to have excellent transparency.
Here, the total amount of solids in the silanol composition is preferably the total amount of the cyclic silanol (A1) and the silica particles.

The silanol composition of the present embodiment preferably further contains a silanol-modified siloxane modified at both ends represented by the following formula (6). As a result, the stress relaxation property is exhibited, and the crack resistance tends to be improved.

In formula (6), R′ is each independently fluorine, an aryl group, a vinyl group, an allyl group, a linear or branched alkyl group having 1 to 4 carbon atoms substituted with fluorine, or It is an unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms, and m is an integer of 0 to 1000.

In the formula (6), R′ is preferably an unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms, more preferably an unsubstituted C 1 carbon atom from the viewpoint of suppressing thermal decomposition. To 2 alkyl groups, more preferably unsubstituted methyl groups.

From the viewpoint of compatibility with the cyclic silanol (A1), the molecular weight of the silanol-modified siloxane modified at both ends represented by the formula (6) is preferably 10000 or less, more preferably 5000 or less, and further preferably 3500. It is as follows.
Further, the molecular weight of the silanol-modified siloxane modified at both ends represented by the above formula (6) is preferably 200 or more, more preferably 300 or more, and further preferably 400 or more from the viewpoint of suppressing volatilization. The molecular weight of the silanol-modified siloxane modified at both ends represented by the above formula (6) can be measured by gel permeation chromatography (GPC).

The both-end silanol-modified siloxane is not limited to the following, but for example, 1,1,3,3-tetramethyldisiloxanediol-1,3-diol, 1,1,3,3,5, 5-hexamethyldisiloxane-1,5-diol, 1,1,3,3,5,5,7,7-octamethyltetrasiloxane-1,7-diol, 1,1,3,3,5, Examples include 5,7,7,9,9-decamethylpentasiloxane-1,9-diol, diol-modified polymethyldimethyldisiloxane modified at both ends.
The silanol-modified siloxane having both terminals may be used alone or in combination of two or more.

A commercially available product may be used as the silanol-modified siloxane having both terminals. Examples of commercially available products include, but are not limited to, X21-5841, KF9701 (all manufactured by Shin-Etsu Chemical Co., Ltd.), and DMS-S12, DMS-S14, DMS-S15, DMS-S21, DMS-S27, DMS-S31, DMS-S32, DMS-S33, DMS-S35, DMS-S42, DMS-S45, DMS-S51 (above made by Gelest) etc. are mentioned.

The content of the silanol-modified siloxane having both terminals at the end in the silanol composition of the present embodiment is preferably 1 to 80% by mass, more preferably 10 to 60% by mass, and still more preferably the amount of silanol composition. It is 15 to 50% by mass. When the content of the silanol-modified siloxane modified at both ends is 1% by mass or more, the resulting cured product tends to have excellent crack resistance. Further, when the content of the silanol-modified siloxane modified at both ends is 80% by mass or less, the obtained cured product tends to have excellent transparency.

The silanol composition of the present embodiment preferably has a total content of sodium (Na) and vanadium (V) of less than 60 ppm. When the total content ratio of Na and V is less than 60 ppm, storage stability tends to be improved. The total content of Na atoms and V atoms in the silanol composition is preferably 20 ppm or less, more preferably 12 ppm or less, even more preferably 2 ppm or less, still more preferably 1 ppm or less. From the viewpoint of storage stability, the content ratio of each of Na and V in the silanol composition of the present embodiment is preferably less than 30 ppm, more preferably 10 ppm or less, and 6 ppm or less. Is more preferable and 1 ppm or less is even more preferable.

The method of controlling the total content ratio of Na and V in the silanol composition of the present embodiment to less than 60 ppm is not limited to the following, but for example, when the silanol composition of the present embodiment is produced. In the filtration step of, the use of powdered cellulose as a filter aid and the like can be mentioned. Commercially available products of powdered cellulose are not limited to the following, but for example, KC Flock W50GK (manufactured by Nippon Paper Industries), KC Flock W100-GK (manufactured by Nippon Paper Industries), cellulose powder 38 μm (400 mesh) passage (Wako Pure). Medicinal product) and the like. Examples of the method for reducing the content ratio of Na and V in the silanol composition to less than 60 ppm include a method using a filter aid containing neither Na nor V, in addition to the method described above.

The content ratios of Na and V in the silanol composition can be measured according to the method described in Examples described later.

(Cured product)
The cured product of this embodiment includes the silanol composition of this embodiment. The cured product of the present embodiment is cured, that is, by the dehydration condensation reaction of the silanol group (-Si-OH) contained in the silanol composition of the present embodiment, a siloxane bond (-Si-O-Si-) is formed. It is obtained by forming and is insoluble in solvents such as tetrahydrofuran and toluene.
One of the present embodiments is a method of curing the silanol composition of the present embodiment.

The cyclic silanol may be polymerized in the absence of a catalyst, or may be polymerized by adding a catalyst. The catalyst used for the polymerization of cyclic silanol functions to accelerate the hydrolysis and condensation reaction of cyclic silanol. An acid catalyst or an alkali catalyst can be used as the catalyst.

The acid catalyst is not particularly limited, for example, hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, hydrofluoric acid, formic acid, acetic acid, propionic acid, butyric acid, valeric acid, hexanoic acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, Suitable are trifluoroacetic acid, oxalic acid, malonic acid, sulfonic acid, phthalic acid, fumaric acid, citric acid, maleic acid, oleic acid, methylmalonic acid, adipic acid, p-aminobenzoic acid, and p-toluenesulfonic acid. Are listed in. The alkali catalyst is not particularly limited, but preferred examples thereof include sodium hydroxide, potassium hydroxide, sodium hydrogen carbonate, sodium carbonate, ammonium carbonate, ammonium hydrogen carbonate, aqueous ammonia, and organic amines. Moreover, when an inorganic base is used, a composition for forming an insulating film containing no metal ions is used. Each of the acid catalyst and the alkali catalyst may be used alone, or two or more kinds may be used in combination.

The amount of the catalyst added can be adjusted depending on the reaction conditions, and is preferably 0.000001 to 2 mol per 1 mol of the hydroxyl group of the cyclic silanol. When the amount added is more than 2 moles per 1 mole of the hydroxyl group of the cyclic silanol, the reaction rate is very fast even at a low concentration, so that it is difficult to control the molecular weight and gelation tends to occur.

When obtaining a cured product, the silanol composition can be subjected to a stepwise hydrolysis and condensation reaction by utilizing an acid catalyst and an alkali catalyst. Specifically, the silanol composition is hydrolyzed and condensed with an acid, and then reacted with a base again, or the hydrolysis and condensation reaction is first performed with a base and then reacted with an acid again. Thus, a cured product can be obtained. Alternatively, the silanol composition can be used by mixing the condensate after reacting with an acid catalyst and an alkali catalyst.

When curing the silanol composition of this embodiment, you may heat. The temperature for curing the cured product is not particularly limited, but is preferably 60 to 250°C, more preferably 80 to 200°C. In the method of curing the silanol composition of the present embodiment, it is preferable to perform heat curing for 10 minutes to 48 hours.

[Ultraviolet light emitting device]
The ultraviolet light emitting device of the present embodiment includes an ultraviolet transparent member, an ultraviolet light emitting element, and a refractive index relaxation material layer disposed between the incident surface of the ultraviolet transparent member and the light extraction surface of the ultraviolet light emitting element. Have. FIG. 1 is a schematic cross-sectional view showing an example of the ultraviolet light emitting device of this embodiment. The ultraviolet light emitting device 100 shown in FIG. 1 is provided with an ultraviolet light transmitting member 2, an ultraviolet light emitting element 1, and a refractive index disposed between an incident surface 110b of the ultraviolet light transmitting member 2 and a light extraction surface 110a of the ultraviolet light emitting element 1. The ultraviolet light emitting element 1 having the relaxing substance layer 3 may be mounted on the mounting substrate 9.

(UV transparent member)
The ultraviolet light transmissive member 2 is made of, for example, a forming material that transmits the ultraviolet light emitted from the ultraviolet light emitting element 1 and is not deteriorated by being irradiated with the ultraviolet light. The forming material is preferably a refractive index relaxing substance, quartz, or sapphire. Examples of the refractive index relaxing substance include the cured product of the present embodiment. The refractive index relaxing substance may contain other substances as long as the effects of the present invention are not impaired. The use of such a forming material is preferable from the viewpoint of improving the light extraction efficiency because there is no difference in the refractive index between the refractive index relaxation substance layer and the ultraviolet-transparent member and no light reflection occurs.

The ultraviolet ray transmissive member is preferably a deep ultraviolet ray transmissive member capable of transmitting deep ultraviolet rays of 210 nm or more and less than 300 nm. This suppresses absorption of deep ultraviolet rays of 210 nm or more and less than 300 nm, which is preferable from the viewpoint of improving the light extraction efficiency.

The ultraviolet transparent member is preferably a lens or a plate member. This reduces reflection at the interface between the ultraviolet-transparent member and the air, which is preferable from the viewpoint of improving the light extraction efficiency.

Further, the lens shape is not limited to a convex shape (hemispherical shape), and may have a bottom surface that is a flat surface to be joined to the light extraction surface 110a of the ultraviolet light emitting element 1. A typical lens shape is shown in FIG. The shape is not limited as long as it is bonded to the light extraction surface of the ultraviolet light emitting element via the refractive index relaxation layer, but a convex spherical shape is preferable and a hemispherical shape is more preferable from the viewpoint of improving the light extraction efficiency. At this time, a dome shape that covers the side wall of the chip may be used. Among these, the lens is preferably a hemispherical lens. In the case of a hemispherical lens, the incident angle of light passing through the lens is close to 90 degrees at the lens-air interface, and the reflection at the interface is suppressed, so that the light extraction efficiency tends to be improved.

Further, it is preferable that the ultraviolet-transmissive member has a size that is at least twice as large as the size (chip size) of the ultraviolet light-emitting element from the viewpoint of improving the light extraction efficiency. As long as it is bonded to the light extraction surface of the ultraviolet light emitting element through the refractive index relaxation layer, the position where the ultraviolet light emitting element and the ultraviolet transparent member (for example, lens) are bonded does not matter, but the light extraction is performed from the viewpoint of improving the light extraction efficiency. It is preferable that the center of the surface and the center of the ultraviolet-transmissive member (for example, lens) are close to each other.

(Ultraviolet light emitting element)
The ultraviolet light emitting element is preferably a deep ultraviolet light emitting element that emits deep ultraviolet light of 210 nm or more and less than 300 nm. As a result, absorption of deep ultraviolet light in the lens is suppressed, and the light extraction efficiency tends to be improved.

The structure of the ultraviolet light emitting element is not particularly limited. As a specific term, a multilayer film (laminated structure) in which a plurality of single crystal layers represented by the composition formula Al _X Ga _Y N (where X and Y are rational numbers satisfying X+Y=1) are laminated. And a structure having The ultraviolet light emitting element is not particularly limited as long as it has the above-mentioned multilayer film portion, but preferably has the following configuration. Specifically, it preferably comprises a substrate, the above-mentioned multilayer film grown on the substrate, and an electrode formed on the multilayer film. That is, the ultraviolet light emitting device can be manufactured by growing the multilayer film on the substrate and then forming the electrodes on the multilayer film.

FIG. 3 is a schematic cross-sectional view showing an example of the ultraviolet light emitting element. The ultraviolet light emitting element 1 shown in FIG. 3 is the same as the ultraviolet light emitting element 1 shown in FIG. As shown in FIG. 3, the ultraviolet light emitting element 1 includes a substrate 111, a multilayer film (N-type semiconductor layer 8, light emitting layer 7, electron block layer 6 and P-type semiconductor layer 5) formed on the substrate 111, An electrode (a positive electrode 4a and a negative electrode 4b) formed on the multilayer film.

(substrate)
When manufacturing the ultraviolet light emitting device chip 1, the substrate is used to grow a multilayer film thereon. The ultraviolet light emitting element has a structure having a multilayer film on the substrate, and when the flip-chip connection is adopted, the surface on the opposite side where the multilayer film does not exist becomes the light extraction surface.

Therefore, the substrate is preferably one on which a single crystal layer represented by the composition formula Al _x Ga _Y N (where X and Y are rational numbers satisfying X+Y=1) can be epitaxially grown. .. Specifically, it is preferable to use commercially available sapphire, aluminum nitride (AlN), or the like. Among them, in consideration of forming a high quality multilayer film, the substrate is preferably formed of aluminum nitride (AlN) single crystal.

The light extraction surface of the ultraviolet light emitting element is preferably formed of an aluminum nitride single crystal. This suppresses the scattering and reflection of light in the crystal, which tends to improve the light extraction efficiency.

When the substrate has low ultraviolet light transmittance, it may be thinned by polishing or the like.

Further, in order to increase the light extraction efficiency, a fine periodic structure having an uneven shape may be provided on the light extraction surface of the substrate by post-processing. The maximum roughness Rz of the rough surface on the back surface is preferably 10 nm or more and 100 μm or less, and more preferably 10 nm or more and 10 μm or less. This processing is not particularly limited, and known methods such as wet/dry etching, surface roughening by sandblasting, and nanoimprint can be adopted.

(Multilayer film)
The multilayer film has a plurality of single crystal layers represented by the composition formula Al _X Ga _Y N (where X and Y are rational numbers satisfying X+Y=1), and can be grown on the substrate. .. Although not limited to the following layers, the multilayer film includes an n-type semiconductor layer (n-type layer), a light emitting layer, an electron block layer, and a p-type semiconductor layer (p-type layer) stacked in this order. It preferably has a laminated structure. Each of these layers is a single crystal layer. Each layer described below can be manufactured by a known method, and is preferably manufactured by the MOCVD method.

The n-type Al _X Ga _Y N (provided that X and Y are rational numbers satisfying X+Y=1) layer preferably contains an n-type impurity. The impurities are not particularly limited, but include Si, Ge, Sn and the like, and preferably Si and Ge. A buffer layer having the same composition as AlN or the group III nitride forming the n-type Al _X Ga _Y N layer may be provided between the substrate and the n-type Al _X Ga _Y N layer. ..

The light emitting layer has a quantum well structure. That is, it is composed of a well layer and a barrier layer represented by the composition formula Al _X Ga _Y N (where X and Y are rational numbers satisfying X+Y=1).

The barrier layer preferably has a bandgap energy larger than that of the well layer. The light emitting layer may have a single quantum well structure or a multiple quantum well structure.

The electron blocking layer is an arbitrary layer, but by providing this electron blocking layer, the electrons supplied from the n-type layer are prevented from overflowing from the light-emitting layer to the p-type layer described in detail below, and are injected. It has the effect of increasing efficiency. The electron block layer is a single crystal layer represented by the composition formula Al _X Ga _Y N (where X and Y are rational numbers satisfying X+Y=1). Further, the electron block layer preferably has a band gap energy larger than those of the barrier layer and the p-type clad layer described in detail below. Further, the electron blocking layer may contain impurities described in the following p-type Al _x Ga _y N layer.

The p-type Al _X Ga _Y N layer is not particularly limited, but is preferably a plurality of layers. Specifically, it is preferably composed of a p-type clad layer and a p-type contact layer. A p-type electrode (positive electrode) is formed on the p-type contact layer.

The p-type cladding layer is a single crystal layer represented by the composition formula Al _X Ga _Y N (where X and Y are rational numbers satisfying X+Y=1). Mg is preferable as the impurity of the p-type cladding layer.

The p-type contact layer is a single crystal layer represented by the composition formula Al _X Ga _Y N (where X and Y are rational numbers that satisfy X+Y=1). As the impurity of the p-type contact layer, Mg is preferable as in the p-type clad layer. From the viewpoint of contact characteristics, the composition of the p-type contact layer is preferably GaN among the above compositions. However, since GaN has an absorption edge at a wavelength of 365 nm, if the GaN layer is too thick, it will not transmit light in the deep ultraviolet region. On the other hand, if the GaN layer is too thin, the current does not spread sufficiently, and the electrical characteristics of the ultraviolet light emitting element chip may deteriorate. Therefore, even when the p-type contact layer is made of GaN, the film thickness is preferably 1 nm or more and 50 nm or less, and more preferably 5 nm or more and 30 nm or less.

〔electrode〕
The negative electrode is formed on the exposed surface of the n-type Al _X Ga _Y N layer. The exposed surface of the n-type Al _X Ga _Y N layer can be formed by etching. Examples of the etching method include dry etching such as reactive ion etching and inductively coupled plasma etching. After forming the exposed surface of the n-type Al _X Ga _Y N layer, it is preferable to perform surface treatment with an acid or alkali solution in order to remove etching damage. Then, a negative electrode having an ohmic property is formed on the exposed surface of the n-type Al _X Ga _Y N layer.

A known method can be adopted for patterning the electrodes. For example, the lift-off method can be used. Examples of the method of depositing the negative electrode metal by the lift-off method include vacuum vapor deposition, sputtering, chemical vapor deposition method, etc., but vacuum vapor deposition is preferable in order to eliminate impurities in the electrode metal. The material used for the negative electrode is not particularly limited and is, for example, Ti, Al, Rh, Cr, In, Ni, Pt, Au, or the like. Above all, it is preferable to use Ti, Al, Rh, Cr, Ni, and Au. These negative electrodes may be a single layer having a layer containing an alloy or oxide of these metals, or a multilayer structure, and a preferable combination from the viewpoint of ohmic property and reflectance is Ti/Al/Ni/Au. is there. After depositing the negative electrode metal, it is preferable to perform heat treatment at a temperature of 300° C. to 1100° C. for 5 seconds to 3 minutes in order to improve the contact property with the n-type layer. Regarding the temperature and time of the heat treatment, the heat treatment may be performed under optimal conditions depending on the metal species and film thickness of the negative electrode.

The positive electrode is formed on the p-type contact layer. For patterning the positive electrode, it is preferable to use the lift-off method as in the patterning of the negative electrode. The metal material used for the positive electrode is not particularly limited, and examples thereof include Ni, Cr, Au, Mg, Zn, Rh, and Pd. Further, the positive electrode may have a single layer having a layer containing an alloy or oxide of these metals, or a multilayer structure. A preferable combination is Ni/Au.

The method of depositing the metal of the positive electrode may be vacuum vapor deposition, sputtering, chemical vapor deposition, or the like, as in the formation of the negative electrode, but vacuum vapor deposition is preferable in order to eliminate impurities in the electrode metal. After depositing the positive electrode metal, it is preferable to perform heat treatment at a temperature of 200° C. to 800° C. for 30 seconds to 3 minutes in order to improve the contact property with the p-type contact layer. Regarding the temperature and time of the heat treatment, the heat treatment may be carried out under suitable conditions depending on the metal species of the positive electrode and the film thickness.

The ultraviolet light emitting device having the layers as described above can be made into one device (chip) by forming each layer and the electrode on the substrate and then separating by a separating method such as scribing, dicing, laser fusing and the like. In the present invention, a wafer in a state before cutting may be used, or a chip may be used.

The ultraviolet light transmissive member is a deep ultraviolet light transmissive member capable of transmitting deep ultraviolet light of 210 nm or more and less than 300 nm, and the ultraviolet light emitting device is a deep ultraviolet light emitting device that emits deep ultraviolet light of 210 nm or more and less than 300 nm. It is preferable.

(Refractive index relaxation material layer)
The refractive index relaxation material layer contains the cured product of the present embodiment. The refractive index relaxing substance layer may contain other substances within a range that does not impair the effects of the present invention.

The thickness of the refractive index relaxing substance layer is not particularly limited, and may be 10 nm to 1 mm, preferably 10 nm to 100 μm, more preferably 10 nm to 20 μm, and further preferably 10 nm to 10 μm. If the thickness of the refractive index relaxation substance layer is too thin, it tends to be difficult to adhere to the lens, and if it is too thick, cracks and peeling are likely to occur due to an increase in internal stress due to silicification and crosslinking of the material associated with deep ultraviolet light. Therefore, the light extraction efficiency of the light emitting element tends to decrease.

(Mounting board)
As the mounting substrate, one used in a commercially available light emitting device package can be used, and from the viewpoint of heat dissipation, an aluminum nitride sintered body, alumina, or a metal substrate is preferable.

The ultraviolet light emitting element is flip-chip mounted on the mounting board, and the terminals provided on the surface of the mounting board and the terminals provided on the ultraviolet light emitting element are electrically connected by ultrasonic waves. A GGI (Gold to Gold Interconnection) method can be used as a method for electrically connecting using ultrasonic waves. This connection method is not particularly limited, and a known method can be adopted.

(Method of manufacturing light emitting device)
Below, the manufacturing method of the light-emitting device of this embodiment is demonstrated. First, the curable composition is applied to the light extraction surface of the ultraviolet light emitting device, the ultraviolet light transmitting member is placed thereon, and a load of 1200 g is applied. After stopping the loading, heating is performed at 60° C. (first heating), and then at 100° C. (second heating). The first heating is to gently evaporate the solvent and prevent the formation of pores in the resin, and the second heating completely evaporates the solvent and hardens the resin. The purpose is to increase the strength and denseness of the refractive index relaxation material.

From the viewpoint of enhancing the adhesiveness with the resin, weighting may be applied during heating in the first and second steps.

Further, from the viewpoint of preventing voids in the resin, the curable composition is applied to the light extraction surface of the ultraviolet light emitting element, the first step of heating is performed to volatilize the solvent, and then the ultraviolet light transmissive material is arranged and weighted. After that, the second stage heating may be performed to bond the light extraction surface of the ultraviolet light emitting element and the ultraviolet light transmitting material. The weight may be applied during the second heating.

Under an environment temperature of 25° C. and a current value of 350 mA, the light output ratio after 100 hours of lighting is preferably 0.9 or more, more preferably 0.93 or more, and more preferably 0.95 or more. Is more preferable.

The ultraviolet light transmissive member is a deep ultraviolet light transmissive member capable of transmitting deep ultraviolet light of 210 nm or more and less than 300 nm, and the ultraviolet light emitting device is a deep ultraviolet light emitting device that emits deep ultraviolet light of 210 nm or more and less than 300 nm.

The present invention also includes components used in the ultraviolet light emitting device of this embodiment. That is, in the present invention, a component for an ultraviolet light emitting device having an ultraviolet light emitting element, and a refractive index relaxation material layer arranged on the light extraction surface of the ultraviolet light emitting element, an ultraviolet transparent member, and the ultraviolet transparent member A light emitting device component having a refractive index relaxation layer disposed on the incident surface is also included.

The present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples and the like.
The method for measuring the physical properties and the method for evaluating the properties of the curable compositions (silanol compositions) obtained by the present invention and the following Examples and Comparative Examples are as follows.

(Calculation of weight percent concentration of coating solution)
Using an ECZ400S manufactured by JEOL Ltd. and a TFH probe as a probe, NMR measurement was performed as follows.
For example, in the case of an isopropanol solution of tetrahydroxytetramethyltetracyclosiloxane and its polymer, 1 g of heavy acetone was added to 0.1 g of an isopropanol solution of tetrahydroxytetramethyltetracyclosiloxane and its polymer, and ¹ 1 H-NMR was measured. The reference peak of the heavy solvent was set to 2.05 ppm, and the number of times of integration was 64.
The weight percent concentration of tetrahydroxytetramethyltetracyclosiloxane and its polymer can be approximately calculated by the following formula.
Weight percentage concentration of tetrahydroxytetramethyltetracyclosiloxane and its polymer=(peak integration ratio of methyl groups bonded to Si in the region of −0.1 to 0.3 ppm/12×304.51)/{(−0 .1 to 0.3 ppm peak integration ratio of methyl group bonded to Si/12×304.51)+(3.7 to 4.1 ppm peak integration value of hydrogen bonded to carbon of isopropanol/ 1×60.1)}
In the above formula, 304.51 means the molecular weight of tetrahydroxytetramethyltetracyclosiloxane, and 60.1 means the molecular weight of isopropanol.

(Measurement of haze)
The haze was measured using a turbidimeter NDH5000W (manufactured by Nippon Denshoku Industries Co., Ltd.) based on JISK7136. The specific operation is shown below.
The haze of the silanol composition was bar coater No. 4 with a 42 wt% isopropanol solution of the silanol composition on a glass substrate 5 cm×5 cm×0.7 mm thick (manufactured by Technoprint Corporation). After coating with 40 (manufactured by AS ONE), it was dried under reduced pressure at 60° C. for 1 hour, and haze was measured. As the blank for haze measurement, only a blank glass substrate having a thickness of 5 cm×5 cm×0.7 mm (manufactured by Technoprint Co., Ltd.) was used.
Regarding Examples 10 and 16 and Comparative Example 1, the haze after 24 hours was also measured.
The haze of the cured product was measured using a sample obtained by heating the sample prepared by the haze measurement of the silanol composition at 100° C. for 2 hours at normal pressure.

(Measurement of film thickness)
The film thickness was measured using a surface shape measuring instrument (manufacturing name: Kosaka Laboratory Ltd., model: ET4000AK31) of the sample prepared for haze measurement, and the film thickness was calculated.

(Confirmation of adhesive strength)
A hemispherical quartz lens having a diameter of 2 mm was placed on the sample prepared by the haze measurement of the silanol composition with a load of 400 g for 3 seconds using a T-3000-FC3 manual die bonder (manufactured by TRESKY). Then, after heating at 100° C. for 2 hours under normal pressure, the glass on which the obtained hemispherical lens was mounted was pushed from the side and the presence or absence of adhesion was confirmed.

(Measurement of area% by GPC of cyclic silanol (A1) and dehydration condensate (A2))
A solution prepared by dissolving 1.5 mL of tetrahydrofuran in 0.03 g of the silanol composition was used as a measurement sample.
This measurement sample was used for measurement with Tosoh Corp. HLC-8220GPC.
As the column, TSK guard columns SuperH-H, TSKgel SuperHM-H, TSKgel SuperHM-H, TSKgel SuperH2000, and TSKgel SuperH1000, manufactured by Tosoh Corporation, were used in series, and tetrahydrofuran was used as a mobile phase at a rate of 0.35 ml/min. analyzed.
An RI detector was used as a detector, and polymethylmethacrylate standard samples (molecular weight: 2100000, 322000, 87800, 20850, 2000, 670000, 130000, 46300, 11800, 860) manufactured by American Polymer Standards Corporation, and 1, 3, 5 , 7-Tetramethylcyclotetrasiloxane (molecular weight 240.5, manufactured by Tokyo Kasei) was used as a standard substance to determine the number average molecular weight and the weight average molecular weight, and the peaks of p=0 and p≧1 were identified, and the cyclic silanol ( The area ratios of the peaks of A1) and the dehydrated condensate (A2) were calculated.

(Contents of Na and V, and content of transition metal (Pd))
Fluorine nitric acid was added to the hydrosiloxane oxidation reaction product, and the sample was transferred to a Teflon (registered trademark) beaker and subjected to heat-drying after being sealed and acid-decomposed. Then, aqua regia was added to the sample, and the completely dissolved solution was adjusted to a constant volume of 20 mL, and quantitative analysis of the metal ratio in the sample was carried out by an ICP mass spectrometer (iCAP Qc manufactured by Thermo Fisher Scientific).

(Calculation of stereoisomer ratio of cyclic silanol using ¹ H-NMR measurement)
Using an ECZ400S manufactured by JEOL Ltd. and a TFH probe as a probe, NMR measurement was performed as follows.
0.1 g of the product and 1 g of heavy acetone were added to the obtained silanol composition, and ¹ H-NMR was measured. The reference peak of the heavy solvent was set to 2.05 ppm, and the number of times of integration was 64.
When tetramethyltetracyclosiloxane is used as a hydrosilane compound as a raw material and is oxidized, ¹ H-NMR of the resulting tetrahydroxytetramethyltetracyclosiloxane shows four isomers in the 0.04-0.95 ppm region. Six types of peaks of methyl groups bonded to Si were observed.
From the high magnetic field side, hydrogen of the methyl group is all-cis type (0.057ppm), trans-trans-cis type (0.064ppm), trans-trans-cis type (0.067ppm), cis-trans-cis. Type (0.074 ppm), all-trans type (0.080 ppm), trans-trans-cis type (0.087 ppm) were observed in this order. Waveform separation by Lorentz transformation was performed on the above six peaks using Delta 5.2.1 (manufactured by JEOL Ltd.), and the stereoisomeric ratio of each cyclic silanol was calculated from the peak intensities of these hydrogens.

(Preparation of each stereoisomer)
・All-cis form (cyclic silanol (B1))
It was synthesized according to the synthesis example of Inorganic Chemistry Vol.49, No.2, 2010.
・Cis-trans-cis form (cyclic silanol (B2))
The recrystallized product obtained in Example 1 was used.
・All-trans form (cyclic silanol (B4))
The mixed solution of tetrahydrofuran and dichloromethane containing 10 wt% of silanol prepared in Example 1 was further concentrated, and the solution concentrated to 20 wt% of silanol was used to fractionate the stereoisomers using liquid chromatography.
<Conditions for liquid chromatography>
Equipment GL Science Liquid Chromatography Pump: PU715
Column oven: CO705
Fraction Collective: FC204YMC-PackSIL-06 φ30mm×250mm
Eluent: Cyclohexane/EtoAc =60/40
Flow rate: 40 mL/min
Injection volume: 5mL
Temperature: 40℃
Detection: The obtained fractions were evaluated and detected by ELSD measurement.
Crystals of the all-trans form were obtained by allowing the obtained eluate of the all-trans form to stand, and the crystals were collected by filtration.
・Trans-trans-cis form (cyclic silanol (B3))
The eluate obtained by the same method as for the all-trans form was concentrated and then replaced with isopropanol.

[Example 1]
(Preparation of silanol composition)
In a reaction vessel, distilled water 28 g, tetrahydrofuran (THF, Wako Pure Chemical Industries, Ltd.) 960 mL, Pd/C (10% palladium-carbon, NE Chemcat Ltd.) 3.7 g were put and mixed, and then the temperature of the reaction vessel Was maintained at 5°C.
Wherein the reaction vessel 1,3,5,7 81g slowly added (Tokyo Kasei, also described as D4H), until after stirring for 2 hours, the SiH group at ¹ H-NMR disappeared 1.8 g of Pd/C (10% palladium/carbon) was divided into 3 times, and the reaction was performed for a total of 17 hours. Regarding the disappearance of the SiH group, ¹ H-NMR of the reaction solution was measured with a heavy acetone solution having a concentration of 1 wt% of the reaction solution using NMR (ECZ400S) manufactured by JEOL Ltd., and the disappearance of 4 to 5 ppm of the SiH group was confirmed.
75 g of magnesium sulfate was added to the reaction solution, and the mixture was stirred at 5° C. for 30 minutes, and then Celite No. 450 g of 545 (manufactured by Wako Pure Chemical Industries, Ltd.) was charged into the funnel using tetrahydrofuran. Subsequently, the reaction solution is passed through the celite, and the celite is washed with 1.5 L of tetrahydrofuran, and 1,3,5,7-tetrahydroxy-1,3,5,7-tetramethyltetracyclosiloxane (hereinafter, 2057 g of a THF solution containing (also referred to as D4OH) was obtained. This solution was concentrated with an evaporator in a water bath at 15° C. until the remaining amount was 587 g (649 mL), and the solution was poured into a mixed solvent of 4.4 L of tetrahydrofuran and 217 mL of dichloromethane. The mixture was allowed to stand at 5° C. for 4 hours, then the precipitated insoluble material was filtered under reduced pressure to recover 22 g of a crystalline solid. 6169 g of the filtrate in the soluble portion was concentrated under reduced pressure to obtain 89 g of a D4OH concentrate (that is, a hydrosiloxane oxidation reaction product).
Further, the D4OH concentrate: both-end silanol-modified siloxane:tetrahydrofuran: siloxane:tetrahydrofuran in a mass ratio of 8:2:90, the both-end silanol-modified siloxane (X21-5841, Shin-Etsu Chemical Co., Ltd., molecular weight 1000) and Tetrahydrofuran was added, and the tetrahydrofuran was distilled off with an evaporator to obtain a silanol composition.
Using the obtained silanol composition, haze was measured according to the method described above (measurement of haze). Further, the ratio of all-trans type and cis-trans-cis type cyclic silanol was calculated by ¹ H-NMR.
Further, the content of the transition metal Pd was calculated as described above.

(Confirmation of curing of silanol composition, confirmation of adhesive strength, and measurement of light transmittance of cured product)
The silanol composition obtained in the above (Preparation of silanol composition) was applied onto a quartz glass using a bar coater No. 2 was applied to a thickness of 3 μm, quartz glass was placed thereon, and cured by a temperature program of 80° C. for 6 hours and 180° C. for 6 hours.
After curing, only one glass plate was lifted, and after confirming that the glass was adhered, the haze of the obtained cured product was measured.

(Check crack resistance after quenching after hardening)
The cured product was taken out from an oven at 180° C. to room temperature at 25° C., rapidly cooled, and cracks were observed with a microscope.

[Example 2]
A silanol composition was obtained in the same manner as in Example 1 except that the mass ratio of the D4OH concentrate: silanol-modified siloxane modified at both ends: tetrahydrofuran was 6:4:90, and the same experiment was conducted. It was

[Example 3]
A silanol composition was obtained in the same manner as in Example 1 except that the both-end silanol-modified siloxane (Shin-Etsu Chemical X21-5841, molecular weight 1000) was replaced with the both-end silanol-modified siloxane (Shin-Etsu Chemical KF-9701, molecular weight 3000). The thing was obtained and the experiment was conducted similarly.

[Example 4]
Both terminal silanol-modified siloxane (Shin-Etsu Chemical X21-5841, molecular weight 1000) was replaced with both-terminal silanol-modified siloxane (Shin-Etsu Chemical KF-9701, molecular weight 3000), and D4OH concentrate: both terminal silanol-modified siloxane: tetrahydrofuran However, a silanol composition was obtained in the same manner as in Example 1 except that the mass ratio was set to 6:4:90, and the same experiment was performed.

[Example 5]
Silanol was modified in the same manner as in Example 1 except that the silanol-modified siloxane with both terminals (X21-5841, Shin-Etsu Chemical Co., Ltd., molecular weight 1000) was replaced with the silanol-modified siloxane with both terminals (DMS-S15, Gelest, molecular weight 2000-3500). The composition was obtained and the same experiment was conducted.

[Example 6]
Both-end silanol-modified siloxane (Shin-Etsu Chemical X21-5841, molecular weight 1000) was replaced with both-end silanol-modified siloxane (Gelest DMS-S15, molecular weight 2000-3500), and D4OH concentrate: Both-end silanol-modified siloxane: A silanol composition was obtained in the same manner as in Example 1 except that the mass ratio of tetrahydrofuran was 6:4:90, and the same experiment was conducted.

[Example 7]
(Preparation of silanol composition)
In a reaction vessel, distilled water 28 g, tetrahydrofuran (THF, Wako Pure Chemical Industries, Ltd.) 960 mL, Pd/C (10% palladium-carbon, NE Chemcat Ltd.) 3.7 g were put and mixed, and then the temperature of the reaction vessel Was maintained at 5°C.
81 g of 1,3,5,7-tetramethylcyclotetrasiloxane (manufactured by Tokyo Kasei, also referred to as D4H) was gradually added to the reaction vessel, and after stirring for 2 hours, SiH group disappeared by ¹ H-NMR. Until then, 1.8 g of the above Pd/C (10% palladium-carbon) was added in 3 batches, and the reaction was carried out for a total of 17 hours.
The reaction solution was subjected to ¹ H-NMR measurement with a heavy acetone solution having a concentration of 1% by mass of the reaction solution using NMR (ECZ400S) manufactured by JEOL Ltd., and the disappearance of 4 to 5 ppm of SiH group was confirmed.
75 g of magnesium sulfate was added to the reaction solution, and the mixture was stirred at 5° C. for 30 minutes, and then Celite No. 450 g of 545 (manufactured by Wako Pure Chemical Industries, Ltd.) was charged into the funnel using tetrahydrofuran. Subsequently, the reaction solution is passed through the celite, and the celite is washed with 1.5 L of tetrahydrofuran, and 1,3,5,7-tetrahydroxy-1,3,5,7-tetramethyltetracyclosiloxane (hereinafter, Also referred to as D4OH) 2057 g of a THF solution containing was obtained.
This solution was concentrated with an evaporator in a water bath at 15° C. until the remaining amount was 587 g (649 mL), and the solution was poured into a mixed solvent of 4.4 L of tetrahydrofuran and 217 mL of dichloromethane. The mixture was allowed to stand at 5° C. for 4 hours, then the precipitated insoluble material was filtered under reduced pressure to recover 22 g of a crystalline solid. 6169 g of the filtrate in the soluble portion was concentrated under reduced pressure to obtain 89 g of a D4OH concentrate (that is, a hydrosiloxane oxidation reaction product).
Furthermore, silica particles (MEKST-40, manufactured by Nissan Chemical Industries, particle size 40 nm) were added to the D4OH concentrate so that the mass ratio was 50:50, and the solid content concentration was 16 mass. A silanol composition (isopropanol solution) was obtained by adding isopropanol so that the ratio became 100%.
Using the obtained silanol composition, haze was measured according to the method described above (measurement of haze), and the peak area in the differential molecular weight distribution curve of GPC was measured. The ratio of all-cis type and cis-trans-cis type cyclic silanols was calculated by ¹ H-NMR.
Further, the content of the transition metal Pd was calculated as described above.

(Confirmation of curing of silanol composition, confirmation of adhesive strength, and measurement of light transmittance of cured product)
8.3 g of the silanol composition obtained in the above (Preparation of silanol composition) was placed on a quartz glass using a bar coater No. It was applied to a thickness of 3 μm using No. 2 and quartz glass was placed thereon and cured by a temperature program of 80° C. for 6 hours and 180° C. for 6 hours.
After curing, only one glass plate was lifted, and after confirming that the glass was adhered, the haze of the obtained cured product was measured.

(Evaluation of wear resistance of cured products)
A bar coater No. 10 was prepared by applying a primer SHP470FT2050 (manufactured by Momentive) to a polycarbonate plate (Taquilon 1600) of 10 cm square and 1 mm thick. After being coated with 16 (manufactured by As One), it was cured in an oven at 30° C. for 30 minutes and 120° C. for 30 minutes to obtain a polycarbonate plate coated with a 2 μm primer.
On the polycarbonate plate, the silanol composition obtained in the above (Preparation of silanol composition) was applied with a bar coater No. After being applied to the polycarbonate plate coated with the primer in 16, the cured plate was obtained by curing in an oven at 100° C. for 2 hours and then at 120° C. for 2 hours.
The obtained cured plate was subjected to a Taber abrasion test for 500 times at a rotation speed of 60 rpm using a 101 TABER TYPE ABRASION TESTER (manufactured by Yasuda) in which CALIBRASE CS-10F (manufactured by TABER INDUSTRIES) was attached to a wear wheel.
In addition, before performing a Taber abrasion test, all the measurement samples used the abrasion wheel ST-11 REFACEING STONE (made by TABER INDUSTRIES), and performed 25 times polishing at the rotation speed of 60 rpm.
The Haze of the measurement sample after the Taber abrasion test was measured using HASE METER NDH 5000SP (manufactured by NIPPON DENSHOKU), and the increase in Haze before and after the Taber abrasion test (ΔHaze (%)) was calculated.

[Example 8]
An experiment similar to that of Example 7 was performed, except that silica particles were added so that the mass ratio of D4OH concentrate:silica was 75:25 (silica addition ratio was 25 wt %).

[Example 9]
(Preparation of silanol composition)
After adding 28 g of distilled water, 960 mL of tetrahydrofuran (THF, Wako Pure Chemical Industries, Ltd.), 3.7 g of Pd/C (10% palladium/carbon, manufactured by NE Chemcat) to the reaction vessel and mixing, temperature of the reaction vessel Was maintained at 5°C.
81 g of 1,3,5,7-tetramethylcyclotetrasiloxane (manufactured by Tokyo Kasei, also referred to as D4H) was gradually added to the reaction vessel, and after stirring for 2 hours, SiH group disappeared by ¹ H-NMR. Until then, 1.8 g of Pd/C (10% palladium/carbon) was added in 3 batches, and the reaction was carried out for a total of 17 hours.
The reaction solution was subjected to ¹ H-NMR measurement with a heavy acetone solution having a concentration of 1% by mass of the reaction solution using NMR (ECZ400S) manufactured by JEOL Ltd., and the disappearance of 4 to 5 ppm of SiH group was confirmed.
After adding 75 g of magnesium sulfate to the reaction solution and stirring the mixture at 5° C. for 30 minutes, 450 g of powdered cellulose KC Flock W50GK (manufactured by Nippon Paper Industries) as a filter aid was charged into the funnel using tetrahydrofuran. Subsequently, the powdery cellulose is passed through the reaction liquid, and the powdery cellulose is washed with 1.5 L of tetrahydrofuran to obtain 1,3,5,7-tetrahydroxy-1,3,5,7-tetramethyltetracyclosiloxane ( Hereinafter, also referred to as D4OH.) 2057 g of a THF solution containing was obtained.
This solution was concentrated with an evaporator in a water bath at 15° C. until the remaining amount was 587 g (649 mL), and the solution was poured into a mixed solvent of 4.4 L of tetrahydrofuran and 217 mL of dichloromethane. The mixture was allowed to stand at 5° C. for 4 hours, then the precipitated insoluble material was filtered under reduced pressure to recover 22 g of a crystalline solid. 6169 g of the filtrate in the soluble portion was concentrated under reduced pressure to obtain a silanol composition (89 g) which was a hydrosiloxane oxidation reaction product.
Using the obtained silanol composition, haze was measured according to the method described above (measurement of haze), and the peak area in the differential molecular weight distribution curve of GPC was measured.
Further, the ratio of all-trans type and cis-trans-cis type cyclic silanol was calculated by ¹ H-NMR. The Na and V contents and the transition metal (Pd) contents were measured as described above.

(Confirmation of curing of silanol composition, confirmation of adhesive strength, measurement of light transmittance of cured product)
8.3 g of the silanol composition obtained in the above (Preparation of silanol composition) was placed on a quartz glass using a bar coater No. 2 was applied to a thickness of 3 μm, quartz glass was further placed thereon, and cured by a temperature program of 80° C. for 6 hours and 180° C. for 6 hours. After curing, only one glass plate was lifted and it was confirmed that the quartz glass was bonded.
Then, the light transmittance in 400-800 nm of the obtained cured product was measured.

(Storage stability test of silanol composition)
The obtained silanol composition was left at room temperature of 25° C. for 1 month.
It was confirmed whether the silanol composition was solidified by touching with a spatula, and the storage stability was evaluated by the presence or absence of solidification.
In the table, ◯ indicates that it did not solidify, and x indicates that it solidified.

[Example 10]
(Preparation of silanol composition)
After adding 28 g of distilled water, 960 mL of tetrahydrofuran (manufactured by Wako Pure Chemical Industries, Ltd.), 3.7 g of Pd/C (10% palladium/carbon, manufactured by NE Chemcat) to the reaction vessel and mixing, the temperature of the reaction vessel was adjusted to 5 Maintained at 0°
Wherein the reaction vessel 1,3,5,7 81g slowly added (Tokyo Kasei, also described as D4H), until after stirring for 2 hours, the SiH group at ¹ H-NMR disappeared 1.8 g of Pd/C (10% palladium/carbon) was divided into 3 times, and the reaction was performed for a total of 17 hours. The disappearance of the SiH group was confirmed by measuring ¹ H-NMR of the reaction solution with a heavy acetone solution having a concentration of 1 wt% of the reaction solution using NMR (ECZ400S) manufactured by JEOL Ltd., and confirming the disappearance of the SiH group existing in 4 to 5 ppm. did.
75 g of magnesium sulfate was added to the reaction solution, and the mixture was stirred at 5°C for 30 minutes. Celite No. 450 g of 545 (manufactured by Wako Pure Chemical Industries, Ltd.) was charged into the funnel using tetrahydrofuran. Subsequently, the reaction solution is passed through the celite, and the celite is washed with 1.5 L of tetrahydrofuran, and 1,3,5,7-tetrahydroxy-1,3,5,7-tetramethyltetracyclosiloxane (hereinafter, 2057 g of a THF solution containing (also referred to as D4OH) was obtained. This solution was concentrated with an evaporator in a water bath at 15° C. until the remaining amount was 587 g (649 mL), and the solution was poured into a mixed solvent of 4.4 L of tetrahydrofuran and 217 mL of dichloromethane. The mixture was allowed to stand at 5° C. for 4 hours, then the precipitated insoluble material was filtered under reduced pressure to recover 22 g of a crystalline solid. 6169 g of the filtrate in the soluble portion was concentrated under reduced pressure, and concentrated to a mixed solution of 10 wt% silanol composition in tetrahydrofuran and dichloromethane. 10 g of a mixed solution of 10 wt% silanol composition in tetrahydrofuran and dichloromethane was concentrated under reduced pressure to 1 g, and then 100 g of isopropanol was added again. Further, the mixture was concentrated again under reduced pressure to prepare a silanol composition (isopropanol solution) having a predetermined concentration.
Physical properties such as haze were evaluated using the obtained silanol composition. Moreover, the stereoisomeric ratio of cyclic silanol was calculated by ¹ H-NMR. FIG. 1 shows the ¹ H-NMR spectrum.

[Example 11]
To the silanol composition (isopropanol solution) prepared in Example 10, the all-trans form (cyclic silanol (B4)) prepared in (Preparation of each stereoisomer) was added, and the all-trans form ratio was 43. The same experiment as in Example 10 was performed except that the percentage was changed to %.

[Example 12]
The all-trans form (cyclic silanol (B4)) prepared in the above (preparation of each stereoisomer) was added to the silanol composition (isopropanol solution) prepared in Example 10 to give an all-trans form ratio of 56. The same experiment as in Example 10 was performed except that the percentage was changed to %.

[Example 13]
The all-cis form (cyclic silanol (B1)) prepared in the above (preparation of each stereoisomer) was added to the silanol composition (isopropanol solution) prepared in Example 10 to adjust the ratio of all-cis form. The same experiment as in Example 10 was performed except that the amount was 31%.

[Example 14]
To the silanol composition (isopropanol solution) prepared in Example 10, the all-cis form (cyclic silanol (B1)) prepared in (Preparation of each stereoisomer) was added, and the all-cis form ratio was 41. The same experiment as in Example 10 was performed except that the percentage was changed to %.

[Example 15]
The trans-trans-cis form (cyclic silanol (B3)) prepared in the above (preparation of stereoisomers) was added to the silanol composition (isopropanol solution) prepared in Example 10 to give trans-trans-cis. The same experiment as in Example 10 was conducted except that the body ratio was set to 66%.

[Example 16]
An experiment similar to that of Example 10 was performed, except that the recrystallization temperature of Example 10 was set to −40° C. FIG. 2 shows the ¹ H-NMR spectrum.

[Examples 1A to 16A]
<Manufacture of ultraviolet light emitting device>
In each of the examples and comparative examples, an ultraviolet light emitting device having the structure shown in FIG. 2 was manufactured. The substrate 111 of the ultraviolet light emitting element chip 1 is an AlN substrate, and the light extraction surface 110a of the light emitting element chip 1 is a square with one side of 0.9 mm and the light emission output is 40 mW or more. A curable composition-containing layer was formed by applying a curable composition as a material for forming the refractive index relaxation material layer 3 to the light extraction surface 110a of the light emitting element chip 1 which is the back surface of the substrate 111. The ultraviolet ray transmitting member is placed thereon, and a load of 1200 g is applied. After the loading was stopped, heating was performed at 60° C. (first heating), and then 100° C. (second heating). As a result, the refractive index relaxation material layer 3 was formed between the light emitting element chip 1 and the hemispherical lens 2, and the ultraviolet light emitting device was obtained.

[Example 17A]
A lens made of quartz having a diameter of 3 mm and a hemispherical shape and having a diameter of 3 mm and a hemispherical shape in place of the lens 2 made of quartz in manufacturing the ultraviolet light emitting device. An ultraviolet light emitting device was obtained in the same manner as in Example 16A except that was used.

[Example 18A]
In manufacturing the ultraviolet light emitting device, it has a diameter of 2 mm and a hemispherical shape, and instead of the lens 2 made of quartz, as shown in FIG. 4, it has a diameter of 2 mm and a plano-convex shape. Then, an ultraviolet light emitting device was obtained in the same manner as in Example 16A except that the lens 2A made of quartz was used.

[Example 19A]
In manufacturing the ultraviolet light emitting device, the lens 2 having a diameter of 2 mm and a hemispherical shape and having a diameter of 2 mm and a rectangular plate shape as shown in FIG. Then, an ultraviolet light emitting device was obtained in the same manner as in Example 16A except that the lens 2B made of quartz was used.

[Example 20A]
In manufacturing the ultraviolet light emitting device, it has a diameter of 2 mm and a hemispherical shape, and instead of the lens 2 made of quartz, as shown in FIG. 6, it has a diameter of 2 mm and a dome shape. An ultraviolet light emitting device was obtained in the same manner as in Example 16A except that the lens 2C made of quartz was used.

[Comparative Example 1]
An ultraviolet light emitting device was obtained in the same manner as in Example 1A except that monomethyl siloxane was used as the material for forming the refractive index relaxation material layer, instead of using the curable composition.
Here, as the monomethylsiloxane, a polymer of methyltrimethoxysilane was used.

[Comparative example 2]
An ultraviolet light emitting device was manufactured in the same manner as in Example 1A, except that "JCR6122 (dimethyl silicone)" manufactured by Dow Corning Co., Ltd. was used as the material for forming the refractive index relaxation material layer instead of the curable composition. Got

[Comparative Example 3]
An ultraviolet light emitting device was produced in the same manner as in Example 1A, except that "HE59N (dimethyl silicone)" manufactured by Yamamura Glass Co., Ltd. was used as the material for forming the refractive index relaxation material layer, instead of using the curable composition. Got

[Comparative Example 4]
An ultraviolet light emitting device was obtained in the same manner as in Example 1A, except that "CYTOP CF3 (fluorine material)" was used as the material for forming the refractive index relaxation material layer, instead of using the curable composition. ..

[Comparative Example 5]
An ultraviolet light emitting device was obtained in the same manner as in Example 1A, except that "Cytop COOH (fluorine material)" was used as the material for forming the refractive index relaxation material layer, instead of using the curable composition. ..

[Evaluation method and result of light output of ultraviolet light emitting device package]
The obtained deep ultraviolet light emitting device was energized using a constant current power supply. The light output value at each current value was measured using an integrating sphere unit, and compared with the light output of a light emitting element (hereinafter referred to as a reference) having a structure that does not have a quartz lens and a refractive index relaxation material, and the ratio thereof. (As the light output ratio) was calculated. The result was 2.0 times, showing that the refractive index relaxation material layer is effective for improving the light extraction efficiency. The light output ratio was constant in the range of the current value up to 500 mA.

[Durability Evaluation Method and Results when Driving Ultraviolet Light Emitting Element]
Using a light emitting device life evaluation device, continuous driving was performed at an environmental temperature of 25° C. and a current value of 350 mA, and the light output was measured at regular intervals. At the same time, the same current was injected into the reference, and the reference was similarly driven for 100 hours for measurement. Relative light output of the sample for evaluation (measured value at each measurement point divided by the light output at the start of the test) and the change in relative light output of the reference are compared, and due to deterioration of the refractive index relaxation material during driving. The reduction in light output was evaluated.

Tables 1 to 5 show the physical properties and evaluation results of the silanol compositions and cured products obtained in Examples and Comparative Examples.

Claims (24)

A curable composition for an ultraviolet light emitting device, which comprises a cyclic silanol (A1) represented by the following formula (1) and a dehydration condensation product (A2) thereof.
(In the formula (1), each R is independently a fluorine atom, an aryl group, a vinyl group, an allyl group, a linear or branched alkyl group having 1 to 4 carbon atoms substituted with fluorine, or a non- It is a substituted linear or branched alkyl group having 1 to 4 carbon atoms, and n is an integer of 2 to 10.) The cyclic silanol (A1) represented by the formula (1) and its dehydrated condensate (A2) are the cyclic silanol (A10) represented by the following formula (10) and its dehydrated condensate (A20). Item 1. A curable composition for an ultraviolet light emitting device according to Item 1.
(In the formula (10), R has the same meaning as R in the formula (1).) The cyclic silanol (A10) is a cyclic silanol (B1) to (B4) represented by the following formulas (2) to (5), and the cyclic silanol (B1) to (B4) relative to the total amount of the cyclic silanol (B1) to (B4). The curable composition for an ultraviolet light emitting device according to claim 2, wherein 0<b≦20 is satisfied when the ratio (mol %) of B2) is b.
(In the formulas (2) to (5), R has the same meaning as R in the formula (1).) The curability for an ultraviolet light emitting device according to claim 3, wherein 0<a≦60 is satisfied, where a is a ratio (mol %) of the cyclic silanol (B1) to the total amount of the cyclic silanols (B1) to (B4). Composition. The curable composition for an ultraviolet light emitting device according to claim 1, which has a haze of 5% or less in the form of a cured product having a thickness of 3 μm. In the peak of the chromatogram obtained by the measurement of gel permeation chromatography, the area of the dehydrated condensate (A2) is 0% with respect to the total area of the cyclic silanol (A1) and the dehydrated condensate (A2). The curable composition for an ultraviolet light emitting device according to any one of claims 1 to 5, which is in excess of 50%. The curable composition for an ultraviolet light emitting device according to claim 1, wherein the content of the transition metal is less than 1 mass ppm. The curable composition for an ultraviolet light emitting device according to claim 1, which comprises a solvent. The curable composition for an ultraviolet light emitting device according to claim 1, further comprising silica particles having an average particle size of 1 nm or more and 100 nm or less. The curable composition for an ultraviolet light emitting device according to claim 1, which comprises a silanol-modified siloxane having both terminals at the end represented by the following general formula (6).
(In the general formula (6), R′ is each independently fluorine, an aryl group, a vinyl group, an allyl group, a linear or branched C 1 -C 4 alkyl group substituted with fluorine, Alternatively, it is an unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms, and m is an integer of 0 to 1000.) The curable composition for an ultraviolet light emitting device according to any one of claims 1 to 10, wherein the total content of Na and V is less than 60 mass ppm. The curable composition for a light emitting device according to claim 1, which is for a deep ultraviolet light emitting device that emits deep ultraviolet light of 210 nm or more and less than 300 nm. A cured product of the curable composition for an ultraviolet light emitting device according to claim 1. An ultraviolet light emitting device component comprising an ultraviolet light emitting element and a refractive index relaxation material layer disposed on a light extraction surface of the ultraviolet light emitting element, wherein the refractive index relaxation material layer contains the cured product according to claim 13. Ultraviolet light emitting device parts. 15. The ultraviolet light emitting device component according to claim 14, wherein the light extraction surface of the ultraviolet light emitting element is formed of an aluminum nitride single crystal. The component for an ultraviolet light emitting device according to claim 14 or 15, wherein the ultraviolet light emitting element is a deep ultraviolet light emitting element that emits deep ultraviolet light of 210 nm or more and less than 300 nm. A component for a light emitting device, which comprises an ultraviolet-transmissive member and a refractive index relaxation layer disposed on an incident surface of the ultraviolet transparent member, wherein the refractive index relaxation material layer contains the cured product of claim 13. Parts for light emitting devices. The ultraviolet light emitting device component according to claim 17, wherein the ultraviolet light transmissive member is a lens or a plate-shaped member. 19. The component for an ultraviolet light emitting device according to claim 18, wherein the lens is a hemispherical lens. 20. The component for an ultraviolet light emitting device according to claim 17, wherein the material for forming the ultraviolet transparent member is a refractive index relaxing substance, quartz, or sapphire. The component for an ultraviolet light emitting device according to any one of claims 17 to 20, wherein the ultraviolet light transmissive member is a deep ultraviolet light transmissive member capable of transmitting deep ultraviolet light of 210 nm or more and less than 300 nm. An ultraviolet light transmitting member, an ultraviolet light emitting element, and a refractive index relaxing substance layer disposed between an incident surface of the ultraviolet transparent member and a light extraction surface of the ultraviolet light emitting device, and the refractive index relaxing substance layer. Is an ultraviolet light emitting device containing the cured product according to claim 13. 23. The ultraviolet light emitting device according to claim 22, wherein a light output ratio after lighting for 100 hours is 0.9 or more under conditions of an ambient temperature of 25° C. and a current value of 350 mA. The ultraviolet light transmissive member is a deep ultraviolet light transmissive member capable of transmitting deep ultraviolet light of 210 nm or more and less than 300 nm, and the ultraviolet light emitting device is a deep ultraviolet light emitting device that emits deep ultraviolet light of 210 nm or more and less than 300 nm. The ultraviolet light emitting device according to claim 22 or 23.