Light emitting device

• US 20040245541A1
• Filed: 12/22/2003
• Published: 12/09/2004
• Est. Priority Date: 12/26/2002
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Seo, Satoshi, Nishi, Takeshi, Shitagaki, Satoko
• Granted Patent: US 7,531,847 B2
• Time in Patent Office: Days
• US Class Current: 257/103
• CPC Class Codes: H05B 33/04 Sealing arrangements , e.g. against humidity
• CPC Class Codes: H05B 33/20 characterised by the chemical or physical composition or the arrangement of the material in which the electroluminescent material is embedded
• CPC Class Codes: H10K 2102/3026 Top emission
• CPC Class Codes: H10K 2102/3031 Two-side emission, e.g. transparent OLEDs [TOLED]
• CPC Class Codes: H10K 50/81 Anodes
• CPC Class Codes: H10K 50/818 Reflective anodes, e.g. ITO combined with thick metallic layers
• CPC Class Codes: H10K 50/828 Transparent cathodes, e.g. comprising thin metal layers
• CPC Class Codes: H10K 50/8426 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: H10K 50/846 comprising getter material or desiccants
• CPC Class Codes: H10K 59/80518 Reflective anodes, e.g. ITO combined with thick metallic layers
• CPC Class Codes: H10K 59/80524 Transparent cathodes, e.g. comprising thin metal layers
• CPC Class Codes: H10K 59/8722 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: H10K 59/874 including getter material or desiccant
• CPC Class Codes: H10K 59/875 Arrangements for extracting light from the devices

Abstract

In a sealing method of a top-emission organic light emitting element, in the case of using a method of filling with a sealing agent between a substrate mounted with pixels and an opposed substrate, the organic light-emitting element is degraded by ultraviolet rays when irradiation of the ultraviolet rays is performed toward the pixels in order to achieve ultraviolet curing of the sealing agent filling on the pixels. It is an object of the present invention to propose a method for avoiding this phenomenon to provide an organic light-emitting device with superior stability. In order for a sealing agent 13 filling on a pixel portion 14 to have a larger absorbance to ultraviolet rays, an ultraviolet-absorbent material is dispersed in a sealing agent to make an adjustment so that the absorbance of ultraviolet absorption wavelength of 400 nm or less becomes 1 or more.

Claims

1. A light-emitting device having an organic light-emitting element of a sequential lamination of a first electrode provided in contact with an insulating surface of a first substrate, an organic light-emitting layer provided in contact with the first electrode and including an electroluminescent organic compound, and a transparent second electrode provided in contact with the organic light-emitting layer, which is provided between the first substrate and a transparent second substrate, characterized in that a sealing agent of an ultraviolet absorbent dispersed in an ultraviolet curable resin is filled between the second electrode and the second substrate and that the sealing agent has an absorbance of 1 or more to a wavelength of ultraviolet rays irradiated for curing the ultraviolet curable resin.

2. The light-emitting device according to claim 1, wherein the wavelength of the ultraviolet rays is 200 nm or more and 400 nm or less.

3. The light-emitting device according to claim 1 or claim 2, wherein the ultraviolet absorbent is moisture-adsorbent.

4. The light-emitting device according to claim 1 or claim 2, wherein the ultraviolet absorbent is oxygen-absorbent.

5. The light-emitting device according to claim 3, wherein the ultraviolet absorbent has a material that absorbs the wavelength region of the ultraviolet rays, which is supported on a porous body.

6. The light-emitting device according to claim 5, wherein the porous body is zeolite.