Ultraviolet Absorbing Sealant for Light-Emitting Devices and Light-Emitting Devices Comprising the Same

Abstract

The present invention relates to an ultraviolet-absorbing sealant for a light-emitting device and a light-emitting device including the ultraviolet-absorbing sealant. By applying an indole compound having an ultraviolet-blocking function and thus having excellent heat and light resistance reliability as the sealant, the physical properties and lifetime characteristics of the light-emitting device can be improved.

Description

Technical Field

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2019-0010387, filed on January 28, 2019, the entire content of which is incorporated herein by reference.

[0002] The present invention relates to a sealant for preventing deterioration of a light-emitting device, and more particularly, to an ultraviolet-absorbing sealant for a light-emitting device and a light-emitting device including the ultraviolet-absorbing sealant. The ultraviolet-absorbing sealant can improve the physical properties and lifetime characteristics of the light-emitting device by applying an indole compound having an ultraviolet-blocking function as the sealant. Background Art

[0003] A light-emitting device, particularly an organic light-emitting device (OLED), is an emitting device that is widely used in various fields due to its advantages of wide viewing angle, good contrast, fast response time, brightness, good operating voltage and response speed characteristics, and possible multiple colors.

[0004] However, if such an organic light-emitting device is exposed to oxygen, moisture, and ultraviolet light, there is a problem that the physical properties and lifetime decrease due to deterioration phenomena. Therefore, a sealing member must be introduced into the device to protect the organic light-emitting device from oxygen, moisture, and ultraviolet light. In particular, since the light-emitting device is exposed to light during use, it should also have light resistance and heat resistance.

[0005] In this regard, in the art, research has been conducted to prevent the device from being damaged by UV by using UV absorbers such as benzophenone absorbers, benzotriazole absorbers, triazole absorbers, triazine absorbers, salicylate absorbers, cyanoacrylate absorbers, oxanilide absorbers, hindered amine absorbers, and metal complex salt absorbers (light stabilizers), and currently, a large number of documents have been published.

[0006] However, since these UV absorbers mainly absorb UV only in the region of 260 nm to 380 nm, there is a problem that they cannot block UV in a region beyond the above region (for example, 380 nm to 430 nm). Therefore, it is necessary to develop a sealant for a light-emitting device that can block UV absorption even in a region above 260 nm to 380 nm to completely prevent UV damage. Summary of the Invention

[0007] Technical Problem

[0008] Accordingly, an object of the present invention is to provide an ultraviolet-absorbing sealant for a light-emitting device and a light-emitting device including the ultraviolet-absorbing sealant. By applying an indole compound having an ultraviolet-blocking function and thus having excellent heat and light resistance reliability as the sealant, the physical properties and life characteristics of the light-emitting device can be improved.

[0009] Technical Solution

[0010] To achieve the above object, the present invention provides an ultraviolet-absorbing sealant for a light-emitting device, which is characterized by containing an indole-derived compound represented by the following formula 1 and having an initial transmittance of the following equation 1 and a light / heat-resistant transmittance of the following equation 2.

[0011] [Formula 1]

[0012]

[0013] [Equation 1]

[0014]

[0015] [Equation 2]

[0016]

[0017] In formula 1, R 1 and R 4 to R 7 are each independently any one selected from hydrogen, hydroxyl, halogen, an alkyl group having 1 to 5 carbon atoms, and an alkoxy group having 1 to 5 carbon atoms, and R 2 and R 3 are each independently a linear, branched or cyclic hydrocarbon group having 4 to 10 carbon atoms, which may or may not have at least one of 1 to 3 nitrogen atoms and oxygen atoms, and in equation 1 and equation 2, T 0 is the initial transmittance at the relevant wavelength, and T 1 is the transmittance at the relevant wavelength after exposure to light.

[0018] In addition, the present invention provides a light-emitting device including the ultraviolet-absorbing sealant for a light-emitting device.

[0019] Beneficial Effects

[0020] The ultraviolet-absorbing sealant for a light-emitting device according to the present invention and the light-emitting device including the ultraviolet-absorbing sealant have the advantage of improving the physical properties and life characteristics of the light-emitting device by applying an indole compound as the sealant, wherein the indole compound has an ultraviolet-blocking function, thereby resulting in excellent heat and light resistance reliability. Detailed Embodiments

[0021] Hereinafter, the present invention will be described in detail.

[0022] The ultraviolet absorption encapsulation material for a light-emitting device according to the present invention is characterized by containing an indole-derived compound represented by the following formula 1, and having an initial transmittance of the following equation 1 and a light / heat-resistant transmittance of the following equation 2.

[0023] [Formula 1]

[0024]

[0025] [Equation 1]

[0026]

[0027] [Equation 2]

[0028]

[0029] In formula 1, R 1 and R 4 to R 7 are each independently any one selected from hydrogen, a hydroxyl group, a halogen, an alkyl group having 1 to 5 carbon atoms, and an alkoxy group having 1 to 5 carbon atoms, and R 2 and R 3 are each independently a linear, branched or cyclic hydrocarbon group having 4 to 10 carbon atoms, which may or may not have any one of 1 to 3 nitrogen atoms and oxygen atoms, and in equations 1 and 2, T 0 is the initial transmittance at the relevant wavelength, and T 1 is the transmittance at the relevant wavelength after exposure to light.

[0030] As described above, heretofore, UV absorbers such as benzophenone compounds, benzotriazole compounds, triazole compounds, triazine compounds, salicylate compounds, cyanoacrylate compounds, oxanilide compounds, hindered amine compounds, and metal complex salts (light stabilizers) have been used to block the UV absorption of light-emitting devices. However, since these UV absorbers mainly absorb UV only in the region of 260 nm to 380 nm, there is a problem that UV in a region beyond the above region (for example, 400 nm to 430 nm) cannot be blocked. Therefore, the applicant of the present invention has invented a sealant for a light-emitting device that can completely prevent UV damage by blocking absorption even in the UV region above 260 nm to 380 nm.

[0031] The reason for selecting 405 nm as the measurement wavelength in Equation 1 and Equation 2 is that there are properties with reduced reliability near 400 nm (such as damage to the yellowing device, etc.) and thus the relevant part should be blocked, and in order to maintain the RGB white balance and increase the transmittance, the transmittance in the blue wavelength range above 430 nm should be high. That is, since it is important to absorb the light near 400 nm that affects the reliability, and in order to ensure the transmittance above 430 nm, 405 nm is selected as the measurement wavelength as described above.

[0032] In Formula 1, R 1 and R 4 to R 7 are each independently any one selected from hydrogen, hydroxyl, halogen, an alkyl group having 1 to 5 carbon atoms, and an alkoxy group having 1 to 5 carbon atoms. R 1 is preferably an alkyl group having 1 to 5 carbon atoms, more preferably methyl, and R 4 to R 7 are preferably hydrogen.

[0033] In addition, in Formula 1, R 2 and R 3 are each independently a linear, branched or cyclic hydrocarbon group having 4 to 10 carbon atoms, which may or may not have any one of 1 to 3 nitrogen atoms and oxygen atoms. Preferably, R 2 and R 3 are each independently a phenyl group, or a saturated or unsaturated (or polymerizable group) hydrocarbon group containing at least one of a cyano group (-CN group), an alkyl group, an alkoxy group, a carbonyl group, a carboxyl group, a hydroxyl group, an amide group, an ester group, an ether group, an acrylate group, and a halogen.

[0034] In Formula 1, specific examples of R 2 and R 3 include and (In the above examples, the curve represents the connecting part), and in addition to these, any substituent satisfying the above conditions can be applied without particular limitation. Furthermore, R 2 and R 3 can be the same or different from each other, but are preferably applied differently from each other. For example, if any one of R 2 and R 3 is a phenyl group, the other can be any one of the other shown substituents.

[0035] Therefore, as the indole-derived compound of the present invention to which the above substituents are applied, compounds represented by Formula 1a to Formula 1j and their isomers can be exemplified.

[0036] [Formula 1a]

[0037]

[0038] [Formula 1b]

[0039]

[0040] [Formula 1c]

[0041]

[0042] [Formula 1d]

[0043]

[0044] [Formula 1e]

[0045]

[0046] [Formula 1f]

[0047]

[0048] [Formula 1g]

[0049]

[0050] [Formula 1h]

[0051]

[0052] [Formula 1i]

[0053]

[0054] [Formula 1j]

[0055]

[0056] Meanwhile, in addition to the indole compounds, the ultraviolet-absorbing sealant for a light-emitting device according to the present invention may further contain at least one UV absorber such as benzophenone compounds, triazole compounds, benzotriazole compounds, triazine compounds, salicylate compounds, cyanoacrylate compounds, oxanilide compounds, hindered amine compounds, and metal complex salts (light stabilizers). Therefore, if a separate UV absorber is additionally contained in addition to the indole compounds, based on 100 parts by weight of the indole compounds, the content of the additional UV absorber may be 0.05 parts by weight to 5 parts by weight. If the content of the additional UV absorber is less than 0.05 parts by weight based on 100 parts by weight of the indole compounds, the blocking effect will not be obvious. If the content of the additional UV absorber exceeds 5 parts by weight based on 100 parts by weight of the indole compounds, an increase in the viscosity of the crude liquid and precipitation will occur, and the long-term stability of the crude liquid will decrease.

[0057] Meanwhile, in addition to the above-mentioned (including indole compounds) UV absorber, the ultraviolet-absorbing sealant for a light-emitting device according to the present invention may further contain a monofunctional acrylate monomer, a polyfunctional acrylate monomer, and a reaction initiator.

[0058] The monofunctional acrylate monomer contains one acrylate functional group and may be exemplified, but not limited to, benzyl methacrylate, 2-hydroxyethyl methacrylate, 4-hydroxybutyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 6-hydroxyhexyl methacrylate, 1,4-cyclohexanedimethanol monomethacrylate, 1-chloro-2-hydroxypropyl methacrylate, diethylene glycol monomethacrylate, 1,6-hexanediol monomethacrylate, 2-hydroxy-3-phenoxypropyl methacrylate, 4-hydroxycyclohexyl methacrylate, 2-hydroxy-3-phenoxybutyl methacrylate, 4-hydroxycyclohexyl methacrylate, and a mixture containing two or more of them.

[0059] The polyfunctional acrylate monomer may contain two or more acrylate functional groups and may contain a polycyclic alicyclic skeleton or a polycyclic aromatic skeleton, and may be exemplified, but not limited to, dipentaerythritol hexaacrylate, triethylene glycol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, isobornyl dimethanol di(meth)acrylate, dicyclopentenyldimethanol di(meth)acrylate, and a mixture containing two or more of them.

[0060] In addition, the reaction initiator may be exemplified by, but not limited to, diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, a reaction initiator having the same or similar properties thereto (i.e., a light absorption wavelength range of 365 nm to 400 nm), and a mixture containing two or more of them.

[0061] Meanwhile, the content of each component constituting the sealant will be described. Based on the total weight of the sealant, the content of the UV absorber (including indole compounds) may be 0.5 wt% to 9 wt%, preferably 1 wt% to 7 wt%, the content of the monofunctional acrylate monomer may be 3 wt% to 95 wt%, preferably 40 wt% to 80 wt%, the content of the polyfunctional acrylate monomer may be 3 wt% to 95 wt%, preferably 15 wt% to 60 wt%, and the content of the initiator may be 0.1 wt% to 5 wt%, preferably 1 wt% to 3 wt%. However, each of these contents is only an optimization for the present invention and is not limited to the above numerical range. If the object of the present invention can be achieved, there is no particular limitation on the content of each component constituting the sealant.

[0062] In addition, the ultraviolet-absorbing sealant for a light-emitting device according to the present invention may further contain one or more additives selected from antioxidants, heat stabilizers, surfactants, leveling agents, and defoaming agents. In this case, the additives may be used without limitation as long as the additives do not inhibit the achievement of the effect of the indole compound.

[0063] Meanwhile, the ultraviolet-absorbing sealant for a light-emitting device according to the present invention has excellent heat / light resistance reliability under ultraviolet light (especially UV in the wavelength range of 405 nm to 430 nm) and conditions of light or heat, thereby preventing the physical properties of the light-emitting device from being degraded, and ultimately improving the lifetime characteristics of the light-emitting device. The ultraviolet-absorbing sealant for a light-emitting device of the present invention as described above has the initial transmittance of Equation 1 and the light / heat-resistant transmittance of Equation 2.

[0064] [Equation 1]

[0065]

[0066] [Equation 2]

[0067]

[0068] In Equations 1 and 2, T 0 is the initial transmittance at the relevant wavelength, and T 1 is the transmittance at the relevant wavelength after exposure to light.

[0069] The ultraviolet absorption sealant for a light-emitting device according to the present invention should substantially satisfy the above Equation 1 (if the transmittance at 405 nm is less than 20%, it all falls within the range of Equation 1), and after light / heat resistance reliability (light resistance, heat resistance), Equation 2 should be satisfied simultaneously (after reliability, when there is a large change at 405 nm, the light / heat resistant transmittance exceeds 10%).

[0070] Here, the UV initial transmittance of the ultraviolet absorption sealant for a light-emitting device at a wavelength of 405 nm to 430 nm can be, for example, 60% to 100%, preferably 80% to 95%, as shown in Equation 1.

[0071] In addition, for example, the light resistance transmittance (light resistance) can be confirmed by measuring the degree of decrease in the transmittance change before and after exposure to light through a UV treatment experiment (280 nm to 400 nm) according to the KS C IEC 61646 standard in accordance with the exposure to sunlight. At this time, the light resistance can be measured under the conditions of exposure to light at 60 °C and 15 kwh / m 2 under the conditions of exposure to light using a 2500W xenon arc lamp according to the standard, and under these conditions, the light resistance should satisfy 10% or less, as shown in Equation 2, and preferably can be 7% or less. At this time, failure to satisfy 10% or less indicates that the blocking performance at 405 nm is reduced due to exposure to light, resulting in a shortened life of the device.

[0072] In addition, the heat resistance transmittance (heat resistance) can be measured, for example, under the condition of heating at a temperature of 120 °C for 500 hours to 1,000 hours, and under these conditions, the heat resistance can be 10% or less, preferably 7% or less, as shown in Equation 2. At the same time, in Equation 2, the term light / heat resistant transmittance is used for convenient description and represents that the light resistance transmittance and the heat resistance transmittance are applied to the same equation.

[0073] At the same time, the present invention provides a light-emitting device including the ultraviolet absorption sealant for a light-emitting device as described above. That is, the ultraviolet absorption sealant according to the present invention is applicable to conventional light-emitting devices such as light-emitting diodes (LEDs) and organic light-emitting devices (OLEDs), and considering the fact that the life of the device is reduced not only due to damage by oxygen and moisture but also by damage from external light, it is preferably applied to organic light-emitting devices. In addition, except for the sealant, the basic structures of the light-emitting device and the organic light-emitting device conform to their conventional basic structures.

[0074] In addition, a method for manufacturing a light-emitting device including the ultraviolet-absorbing sealant will be briefly described. First, the ultraviolet-absorbing sealant for a light-emitting device is coated on an LED or an OLED by a coating method such as flash evaporation, inkjet printing, or spin coating, cured by UV, then molded into a thin sheet, etc., bonded to a substrate, and thermally cured to manufacture a light-emitting device including the sealant.

[0075] Hereinafter, preferred embodiments are provided to assist in understanding the present invention, but the following embodiments are only illustrative of the present invention. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope and spirit of the present invention, and such changes and modifications are within the scope of the appended claims.

[0076] Example 1: Manufacturing an ultraviolet-absorbing sealant

[0077] Into a three-necked flask equipped with a stirrer, 56.87 wt% of benzyl methacrylate monomer, 37.92 wt% of trimethylolpropane triacrylate as a polyfunctional acrylate monomer, 2.84 wt% of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide as an initiator, and 2.37 wt% of an indole-derived compound represented by Formula 1a were added, and then stirred at 550 rpm for 5 hours under a nitrogen atmosphere and at a temperature of 50 °C. After applying the compound obtained by stirring on a glass substrate at a speed of 880 rpm using a spin coater (ACE-200, DongAh Trade Corp) for 23 seconds, the compound was cured at a temperature of 25 °C with a light amount of 1,500 mJ / cm 2 by an LED curing machine at a wavelength of 395 nm under a nitrogen atmosphere to manufacture an ultraviolet-absorbing sealant for a light-emitting device having a thickness of 8 μm.

[0078] [Formula 1a]

[0079]

[0080] Example 2: Manufacturing an ultraviolet-absorbing sealant

[0081] An ultraviolet-absorbing sealant for a light-emitting device was manufactured in the same manner as in Example 1, except that the indole-derived compound of Formula 1a was changed to an indole-derived compound represented by Formula 1b.

[0082] [Formula 1b]

[0083]

[0084] Example 3: Manufacturing an ultraviolet-absorbing sealant

[0085] Except for changing the indole-derived compound of Formula 1a to the indole-derived compound represented by Formula 1c, an ultraviolet-absorbing sealant for a light-emitting device was produced in the same manner as in Example 1.

[0086] [Formula 1c]

[0087]

[0088] Example 4: Manufacturing an ultraviolet-absorbing sealant

[0089] Except for changing the indole-derived compound of Formula 1a to the indole-derived compound represented by Formula 1d, an ultraviolet-absorbing sealant for a light-emitting device was produced in the same manner as in Example 1.

[0090] [Formula 1d]

[0091]

[0092] Example 5: Manufacturing an ultraviolet-absorbing sealant

[0093] Except for changing the indole-derived compound of Formula 1a to the indole-derived compound represented by Formula 1e, an ultraviolet-absorbing sealant for a light-emitting device was produced in the same manner as in Example 1.

[0094] [Formula 1e]

[0095]

[0096] Example 6: Manufacturing an ultraviolet-absorbing sealant

[0097] Except for changing the indole-derived compound of Formula 1a to the indole-derived compound represented by Formula 1f, an ultraviolet-absorbing sealant for a light-emitting device was produced in the same manner as in Example 1.

[0098] [Formula 1f]

[0099]

[0100] Example 7: Manufacturing an ultraviolet-absorbing sealant

[0101] Except for changing the indole-derived compound of Formula 1a to the indole-derived compound represented by Formula 1g, an ultraviolet-absorbing sealant for a light-emitting device was produced in the same manner as in Example 1.

[0102] [Formula 1g]

[0103]

[0104] Example 8: Manufacturing an ultraviolet-absorbing sealant

[0105] An ultraviolet-absorbing sealant for a light-emitting device was produced in the same manner as in Example 1, except that the indole-derived compound of Formula 1a was changed to an indole-derived compound represented by Formula 1h.

[0106] [Formula 1h]

[0107]

[0108] Example 9: Manufacturing an ultraviolet-absorbing sealant

[0109] An ultraviolet-absorbing sealant for a light-emitting device was produced in the same manner as in Example 1, except that the indole-derived compound of Formula 1a was changed to an indole-derived compound represented by Formula 1i.

[0110] [Formula 1i]

[0111]

[0112] Example 10: Manufacturing an ultraviolet-absorbing sealant

[0113] An ultraviolet-absorbing sealant for a light-emitting device was produced in the same manner as in Example 1, except that the indole-derived compound of Formula 1a was changed to an indole-derived compound represented by Formula 1j.

[0114] [Formula 1j]

[0115]

[0116] Comparative Example 1: Manufacturing a sealant

[0117] A sealant for a light-emitting device was produced in the same manner as in Example 1, except that the indole-derived compound of Formula 1a was changed to a triazine-based UV absorber (BASF Tinuvin-460).

[0118] Comparative Example 2: Manufacturing a sealant

[0119] A sealant for a light-emitting device was produced in the same manner as in Example 1, except that the indole-derived compound of Formula 1a was changed to a benzotriazole-based UV absorber (BASF Tinuvin-P).

[0120] Comparative Example 3: Manufacturing a sealant

[0121] A sealant for a light-emitting device was produced in the same manner as in Example 1, except that the indole-derived compound of Formula 1a was changed to a benzophenone-based UV absorber (BASF Chimassorb-81).

[0122] Experimental Example 1: Evaluating the initial transmittance of a sealant for an organic light-emitting device

[0123] The transmittance of the sealant specimens prepared in Examples 1 to 10 and Comparative Examples 1 to 3 was measured at 300 nm to 800 nm in transmission mode using an ultraviolet-visible spectrometer (Evolution 600), and the results are shown in Table 1 below.

[0124] [Table 1]

[0125] Initial transmittance (%) Example 1 89.3 Example 2 83.0 Example 3 76.2 Example 4 89.2 Example 5 92.4 Example 6 65.4 Example 7 91.3 Example 8 88.2 Example 9 89.3 Example 10 90.2 Comparative Example 1 2.9 Comparative Example 2 0.9 Comparative Example 3 1.3

[0126] As the evaluation result of the initial transmittance of the sealants prepared in Examples 1 to 10 and Comparative Examples 1 to 3, it can be confirmed that the sealants of Examples 1 to 10 to which the indole-derived compound of the present invention is applied have significantly excellent initial transmittance compared with the sealants of Comparative Examples 1 to 3. Thus, it can be seen that if the indole-derived compound of the present invention is applied to the sealant, it blocks light near 400 nm.

[0127] Experimental Example 2: Evaluating the light resistance transmittance of a sealant for an organic light-emitting device

[0128] Using a lightfastness tester (Daesong Labtech, Korea), according to the KS C IEC 61646 standard (280 nm to 400 nm), through a UV treatment test, when the sealants prepared in Examples 1 to 10 and Comparative Examples 1 to 3 were exposed to sunlight, the change in transmittance before and after exposure was measured to measure the degree of deterioration. At this time, each encapsulation material was evaluated for its lightfast transmittance by exposing it to light at a temperature of 60 °C and a light amount of 15 kwh / m 2 using a 2500 W xenon arc lamp according to the standard, and the results are shown in Table 2 below.

[0129] Experimental Example 3: Evaluating the heat resistance transmittance of a sealant for an organic light-emitting device

[0130] For the sealants prepared in Examples 1 to 10 and Comparative Examples 1 to 3, the heat-resistant transmittance of each sealant was evaluated by heating it in air at 120 °C for 500 hours using a high-temperature oven (JEIO Tech, Korea), and the results are shown in Table 2 below.

[0131] [Table 2]

[0132] Light resistance transmittance (%) Heat resistance transmittance (%) Example 1 4 3 Example 2 9 4 Example 3 9 2 Example 4 7 3 Example 5 2 1 Example 6 10 4 Example 7 2 1 Example 8 4 2 Example 9 4 2 Example 10 4 3 Comparative Example 1 -1 1 Comparative Example 2 -2 2 Comparative Example 3 -1 -1

[0133] As a result of evaluating the light resistance and heat resistance of the sealants prepared in Examples 1 to 10 and Comparative Examples 1 to 3 in Experimental Example 2 and Experimental Example 3, it was confirmed that the sealants of Examples 1 to 10 to which the indole-derived compound of the present invention was applied had excellent light-blocking effects even after heat / light resistance at short wavelengths of 405 nm to 430 nm.

Claims

1. An ultraviolet light-absorbing sealant for a light-emitting device, the ultraviolet light-absorbing sealant comprising an indole-derived compound selected from the compounds represented by Formula 1b, Formula 1c, Formula 1e, Formula 1f, Formula 1h, and Formula 1j below, and having an initial transmittance of Equation 1 below and a light / heat-resistant transmittance of Equation 2 below: [Formula 1b] [Formula 1c] [Formula 1e] [Formula 1f] [Formula 1h] [Formula 1j] [Equation 1] [Equation 2] Wherein, In Equations 1 and 2, T 0 is the initial transmittance at the relevant wavelength, and T 1 is the transmittance at the relevant wavelength after exposure to light.

2. The ultraviolet light-absorbing sealant for a light-emitting device according to claim 1, Wherein, the UV initial transmittance of the ultraviolet light-absorbing sealant at a wavelength of 405 nm to 430 nm is 80% to 95%.

3. The ultraviolet light-absorbing sealant for a light-emitting device according to claim 1, Wherein, the light-resistant transmittance and heat-resistant transmittance of the ultraviolet light-absorbing sealant are 7% or less.

4. The ultraviolet light-absorbing sealant for a light-emitting device according to claim 1, Wherein, the ultraviolet light-absorbing sealant further comprises at least one UV absorber selected from benzophenone compounds, triazole compounds, benzotriazole compounds, triazine compounds, salicylate compounds, cyanoacrylate compounds, oxanilide compounds, hindered amine compounds, and metal complex salts compounds.

5. The ultraviolet light-absorbing sealant for a light-emitting device according to claim 1, Wherein, the ultraviolet light-absorbing sealant further comprises one or more additives selected from antioxidants, heat stabilizers, surfactants, leveling agents, and defoaming agents.

6. The ultraviolet light-absorbing sealant for a light-emitting device according to claim 1, Wherein, the light-emitting device is an LED or an OLED.

7. A light-emitting device comprising the ultraviolet light-absorbing sealant for a light-emitting device according to claim 1.

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