Organic electroluminescence element-use transparent substrate and element

• US 20080075849A1
• Filed: 11/16/2007
• Published: 03/27/2008
• Est. Priority Date: 09/12/2001
• Status: Abandoned Application

• Current Assignee: Nissan Chemical Industries Limited (Nissan Chemical Corporation)
• Original Assignee: Nissan Chemical Industries Limited (Nissan Chemical Corporation)
• Inventors: OOTSUKA, Yoshikazu, Abe, Toyohiko, Motoyama, Kenichi
• Application Number:
  US11/941,581
• Publication Number:
  US 20080075849A1
• Time in Patent Office: Days
• US Class Current: 427/169
• CPC Class Codes: H10K 50/80 Constructional details
• CPC Class Codes: H10K 50/85 Arrangements for extracting light from the devices
• CPC Class Codes: H10K 59/875 Arrangements for extracting light from the devices
• CPC Class Codes: H10K 77/10 Substrates, e.g. flexible substrates
• CPC Class Codes: H10K 85/111 comprising aromatic, heteroaromatic, or aryl chains, e.g. polyaniline, polyphenylene or polyphenylene vinylene
• CPC Class Codes: H10K 85/324 comprising aluminium, e.g. Alq3
• CPC Class Codes: H10K 85/631 Amine compounds having at least two aryl rest on at least one amine-nitrogen atom, e.g. triphenylamine
• CPC Class Codes: Y02E 10/549 Organic PV cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10T 428/24942 including components having same physical characteristic in differing degree
• CPC Class Codes: Y10T 428/2495 Thickness [relative or absolute]
• CPC Class Codes: Y10T 428/31504 Composite [nonstructural laminate]

Abstract

The present invention provides a transparent substrate capable of improving the light extraction efficiency of an organic electroluminescence device, and an organic electroluminescence device with high luminous efficiency and with excellent mass productivity using the substrate. The present invention relates to a transparent substrate for an organic electroluminescence device characterized in that an optical interference film comprising at least one layer having such a refractive index and a film thickness as to reduce a quantity of reflection of light emitted from a light-emitting layer is provided on both sides of the transparent substrate in the organic electroluminescence device, and to an organic electroluminescence device comprising the transparent substrate.

Claims

1-9. -9. (canceled)

10. A method, comprising:

improving the light extraction efficiency of a transparent substrate through which light is to be viewed for an organic electroluminescent device by providing each side of a transparent substrate with an optical interference film comprising at least one layer having such a refractive index and a film thickness as to reduce the quantity of reflected light that is emitted from a light-emitting layer, wherein each optical interference film is a multilayer film which is a sequential stack of a high refractive index film and a low refractive index film, the high and low refractive index films having a difference in refractive indices of 0.01 to 1.00, or said multilayer film is comprised of films having different thicknesses, with the thicknesses of the respective films being N times a quarter of the center wavelength of the visible spectrum and N times half of the center wavelength of the visible spectrum.

11. The method according to claim 10, wherein each optical interference film has a refractive index ranging from 1.1 to 2.3 and a film thickness ranging from 10 to 25,000 nm.

12. The method according to claim 10, wherein the transparent substrate is a silica glass, a soda glass or an organic film.

13. A method, comprising:

improving the light extraction efficiency of a transparent substrate through which light is to be viewed for an organic electroluminescent device by providing each side of a transparent substrate with an optical interference film comprising at least one layer having such a refractive index and a film thickness as to reduce the quantity of reflected light of the light emitted from a light-emitting layer, wherein each optical interference film is prepared by applying a sol-gel material of a metal oxide onto the transparent substrate and baking the material, and wherein each optical interference film is a multilayer film which is a sequential stack of a high refractive index film and a low refractive index film, the high and low refractive index films having a difference in refractive indices of 0.01 to 1.00, or said multilayer film is comprised of films having different thicknesses, with the thicknesses of the respective films being N times a quarter of the center wavelength of the visible spectrum and N times half of the center wavelength of the visible spectrum.

14. The method according to claim 13, wherein each optical interference film has a refractive index ranging from 1.1 to 2.3 and a film thickness ranging from 10 to 25,000 nm.

15. The method according to claim 13, wherein the sol-gel material of the metal oxide results from polycondensation of a metal alkoxide in an organic solvent in the presence of an acidic compound or a basic compound.

16. The method according to claim 15, wherein the metal alkoxide is an alkoxysilane, or a tetraalkoxide compound of titanium, zirconium, aluminum or tantalum.

17. The method according to claim 13, wherein the optical interference film is obtained by forming a film of a sol-gel material of a metal oxide on each side of the transparent substrate by a dip method and baking the film.

18. The method according to claim 13, wherein the transparent substrate is a silica glass, a soda glass or an organic film.

19. An method of preparing an organic electroluminescence device, comprising:

providing each side of a transparent substrate with an optical interference film comprising at least one layer having such a refractive index and a film thickness as to reduce the quantity of reflected light of the light emitted from a light-emitting layer.

20. A method of preparing an organic electroluminescence device, comprising:

providing each side of a transparent substrate with an optical interference film comprising at least one layer having such a refractive index and a film thickness as to reduce the quantity of reflected light of the light emitted from a light-emitting layer, by applying a sol-gel material of a metal oxide onto each surface of a transparent substrate and then baking the material.