Electroluminescence display device having a desiccant

• US 6,833,668 B1
• Filed: 09/07/2000
• Issued: 12/21/2004
• Est. Priority Date: 09/29/1999
• Status: Expired due to Term

• Current Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Yamada, Tsutomu, Komiya, Naoaki
• Primary Examiner(s): WILLIAMS, JOSEPH L
• Application Number:
  US09/656,482
• Time in Patent Office: 1,566 Days
• Field of Search: 313/505, 313/502, 313/503, 313/509, 313/506, 313/504, 313/483, 313/500, 313/498-512, 313/9
• US Class Current: 313/505
• CPC Class Codes: H10K 2102/3026 Top emission
• CPC Class Codes: H10K 50/80 Constructional details
• CPC Class Codes: H10K 50/8426 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: H10K 50/8428 Vertical spacers, e.g. arranged between the sealing arrangement and the OLED
• CPC Class Codes: H10K 50/846 comprising getter material or desiccants
• CPC Class Codes: H10K 50/86 Arrangements for improving contrast, e.g. preventing reflection of ambient light
• CPC Class Codes: H10K 50/865 comprising light absorbing layers, e.g. light-blocking layers
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays
• CPC Class Codes: H10K 59/126 Shielding, e.g. light-blocking means over the TFTs
• CPC Class Codes: H10K 59/38 comprising colour filters or colour changing media [CCM]
• CPC Class Codes: H10K 59/8722 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: H10K 59/8723 Vertical spacers, e.g. arranged between the sealing arrangement and the OLED
• CPC Class Codes: H10K 59/874 including getter material or desiccant
• CPC Class Codes: H10K 59/8792 comprising light absorbing layers, e.g. black layers

Abstract

Powder desiccant is mixed into a seal which adheres a first substrate to a second substrate, thereby sealing a display region. Almost no moisture permeates through the outer surfaces of the substrates sandwiching the display region, while moisture permeating through the seal is adsorbed by the desiccant. An emissive layer is thereby prevented from deterioration due to moisture. By covering the display region with a resin sealing layer composed of resin having desiccant mixed therein, the display region can reliably be protected from moisture. By forming a groove in the substrate and placing a desiccant therein, moisture can be further reliably adsorbed.

Claims

1. An organic electroluminescent display device in which a display region having an organic electroluminescent element is formed between a pair of substrates, wherein

said organic electroluminescent element comprises a first electrode, a second electrode, and an organic electroluminescent layer formed between said first and second electrodes, said organic electroluminescent layer emitting light when electric current flows between said first and second electrodes, and

a resin having a desiccant mixed therein is disposed between said pair of substrates, wherein

said pair of substrates are adhered to one another by a sealing material disposed surrounding at least said display region, so as to seal said display region including said organic electroluminescent element.

2. The display device as defined in claim 1, wherein

said resin having said desiccant mixed therein is used as said sealing material.

3. The display device as defined in claim 2, wherein

said resin having said desiccant mixed therein is a resin cured by ultraviolet irradiation.

4. A display device as defined in claim 1, wherein

said desiccant is a substance having a chemically adsorptive property.

5. An organic electroluminescent display device in which a display region having an organic electroluminescent element is formed between a pair of substrates, wherein

said organic electroluminescent element comprises a first electrode, a second electrode, and an organic electroluminescent layer formed between said first and second electrodes, said organic electroluminescent layer emitting light when electric current flows between said first and second electrodes, and

a resin having a desiccant mixed therein is disposed between said pair of substrates, wherein

said resin is disposed surrounding said display region.

6. The display device as defined in claim 5, wherein

said display region having said organic electroluminescent is formed on a first substrate among said pair of substrates;

a second substrate among said pair of substrates is arranged facing the display region side of said first substrate and adhered to said first substrate;

a color component is provided in a gap between said second substrate and said display region; and

said second substrate is a transparent substrate which transmits at least visible light.

7. The display device as defined in claim 5, wherein

said display region having said organic electroluminescent is formed on a first substrate among said pair of substrates;

a second substrate among said pair of substrates is arranged facing the display region side of said first substrate and adhered to said first substrate; and

a spacer composed of a desiccant is provided in a gap between said second substrate and said display region.

8. The display device as defined in claim 5, wherein

said desiccant is mixed in said resin at a ratio of at least 10 wt %, but no more than 50 wt %.

9. The display device as defined in claim 5, wherein

said resin having said desiccant mixed therein is a resin cured by ultraviolet irradiation.

10. A display device in which a display region having a self-emissive element is formed between a pair of substrates, wherein

a resin having a desiccant mixed therein is disposed between said pair of substrates, and

said resin having said desiccant mixed therein is located in a gap between said pair of substrates and covers at least said display region.

11. The display device as defined in claim 10, wherein

said resin having said desiccant mixed therein is a resin cured by ultraviolet irradiation.

12. The electroluminescence display device as defined in claim 11, wherein

a desiccant is mixed in said coating resin layer.

13. The electroluminescence display device as defined in claim 11, wherein

said coating resin layer having said desiccant mixed therein covers said self-emissive element and fills a gap between said first and said second substrates.

14. The electroluminescence display device as defined in claim 11, wherein

said self-emissive element is composed by laminating, in order from the first substrate side, said first electrode, said emissive element layer, and said second electrode;

and

said coating resin layer covers said self-emissive element from the second substrate side.

15. The electroluminescence display device as defined in claim 11, wherein

a light-shielding layer for blocking ultraviolet rays is disposed between said emissive element layer and said coating resin layer.

16. The electroluminescence display device as defined in claim 15, wherein

said, second electrode simultaneously serves as said light-shielding layer.

17. The electroluminescence display device as defined in claim 16, wherein

a desiccant is mixed in said coating resin layer.

18. The electroluminescence display device as defined in claim 16, wherein

said desiccant is a powder having a particle diameter of 20 μ

m or less.

19. The electroluminescence display device as defined in claim 11, wherein said desiccant is mixed in a resin constituting said coating resin layer at a ratio of at least 10 wt %, but no more than 50 wt %.

20. The display device as defined in claim 10, wherein

said resin having said desiccant mixed therein fills said gap between said pair of substrates.

21. A display device as defined in claim 10, wherein

a resin having a desiccant mixed therein is disposed between said pair of substrates, and

said desiccant is a powder having a particle diameter of 20 μ

m or less.

22. The display device as defined in claim 10, wherein

said desiccant is mixed in said resin at a ratio of at least 10 wt %, but no more than 50 wt %.

23. A display device in which a display region having a self-emissive element is formed between a pair of substrates, wherein

said pair of substrates are adhered to one another by a sealing material disposed surrounding at least said display region, so as to seal said display region;

a groove is formed in at least one of said pair of substrates on a side facing the other substrate in a location where said sealing material is disposed; and

a desiccant is filled in said groove.

24. The display device as defined in claim 23, wherein

a resin having a desiccant mixed therein is used as said sealing material.

25. The display device as defined in claim 24, wherein

said resin having said desiccant mixed therein is a resin cured by ultraviolet irradiation.

26. The display device as defined in claim 23, wherein

said self-emissive element is an electroluminescence element.

27. The display device as defined in claim 26, wherein

said display region having said self-emissive element is formed on a first substrate among said pair of substrates;

a second substrate among said pair of substrates is arranged facing the display region side of said first substrate and adhered to said first substrate;

a color component is provided in a gap between said second substrate and said display region; and

said second substrate is a transparent substrate which transmits at least visible light.

28. The display device as defined in claim 26, wherein

said display region having said self-emissive element is formed on a first substrate among said pair of substrates;

a second substrate among said pair of substrates is arranged facing the display region side of said first substrate and adhered to said first substrate; and

a spacer composed of a desiccant is provided in a gap between said second substrate and said display region.

29. The display device as defined in claim 23, wherein

said self-emissive element is an organic electroluminescence element containing an organic compound in an emissive element layer.

30. The display device as defined in claim 23, wherein

said resin having said desiccant mixed therein is located in a gap between said pair of substrates and covers at least said display region.

31. The display device as defined in claim 30, wherein

said resin having said desiccant mixed therein fills said gap between said pair of substrates.

32. The display device as defined in claim 23, wherein

said desiccant is a substance having a chemically adsorptive property.

33. The display device as defined in claim 23, wherein said desiccant is a powder having a particle diameter of 20 μ

m or less.

34. The display device as defined in claim 23, wherein

said desiccant is mixed in said resin at a ratio of at least 10 wt %, but no more than 50 wt %.

35. A light-emitting device in which an emissive region having a self-emissive element is formed between a pair of substrates, wherein

said pair of substrates are adhered to one another by a sealing material disposed surrounding at least said emissive region, so as to seal said emissive region;

a groove is formed in at least one of said pair of substrates on a side facing the other substrate in a location where said sealing material is disposed; and

a desiccant is filled in said groove.

36. A display device in which a display region having a self-emissive element is formed between a pair of substrates, wherein

said self-emissive element comprises a first electrode, a second electrode, and an emissive layer formed between said first and second electrodes, and

a resin having a desiccant mixed therein is disposed between said pair of substrates such that said resin surrounds said self-emissive element comprising said first electrode, said emissive layer, and said second electrode.

37. The display device as defined in claim 36, wherein

said pair of substrates are adhered to one another by a sealing material disposed surrounding at least said display region, so as to seal said display region including said self-emissive element.

38. The display device as defined in claim 37, wherein

said resin having said desiccant mixed therein is used as said sealing material.

39. The display device as defined in claim 38, wherein

said resin having said desiccant mixed therein is a resin cured by ultraviolet irradiation.

40. The display device as defined in claim 36, wherein

said self-emissive element is an electroluminescence element.

41. The display device as defined in claim 40, wherein

said display region having said self-emissive element is formed on a first substrate among said pair of substrates;

a second substrate among said pair of substrates is arranged facing the display region side of said first substrate and adhered to said first substrate;

a color component is provided in a gap between said second substrate and said display region; and

said second substrate is a transparent substrate which transmits at least visible light.

42. The display device as defined in claim 40, wherein

said display region having said self-emissive element is formed on a first substrate among said pair of substrates;

a second substrate among said pair of substrates is arranged facing the display region side of said first substrate and adhered to said first substrate; and

a spacer composed of a desiccant is provided in a gap between said second substrate and said display region.

43. The display device as defined in claim 36, wherein

said self-emissive element is an organic electroluminescence element containing an organic compound in an emissive element layer.

44. The display device as defined in claim 36, wherein

said desiccant is mixed in said resin at a ratio of at least 10 wt %, but no more than 50 wt %.