Organic electroluminescent device

• US 5,693,428 A
• Filed: 02/02/1996
• Issued: 12/02/1997
• Est. Priority Date: 02/06/1995
• Status: Expired due to Term

• Current Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Takeuchi, Kousuke, Sano, Takeshi, Shibata, Kenichi, Hamada, Yuji, Fujii, Takanori
• Primary Examiner(s): NOLD, CHARLES R
• Application Number:
  US08/596,415
• Time in Patent Office: 669 Days
• Field of Search: 428/690, 428/691, 428/917, 313/504
• US Class Current: 428/690
• CPC Class Codes: H05B 33/14 characterised by the chemical or physical composition or the arrangement of the electroluminescent material , or by the simultaneous addition of the electroluminescent material in or onto the light source
• CPC Class Codes: H10K 59/221 Static displays, e.g. displaying permanent logos
• CPC Class Codes: Y10S 428/917 Electroluminescent

Abstract

In an organic electroluminescent device according to the present invention, at least a carrier transporting layer and a luminescent layer which use an organic material are provided between a hole injection electrode and an electron injection electrode, wherein a luminescent portion having a luminescent peak wavelength different from a luminescent peak wavelength in the luminescent layer is partially provided in such a manner that it is laminated on the luminescent layer, or at least a hole transporting layer having luminous characteristics and an electron transporting layer having luminous characteristics which respectively contain organic materials emitting fluorescence in different colors in a visible region are provided between the hole injection electrode and the electron injection electrode, wherein a hole transporting portion having non-luminous characteristics is partially provided between the hole transporting layer having luminous characteristics and the electron transporting layer having luminous characteristics when the hole transporting layer having luminous characteristics emits light, while an electron transporting portion having non-luminous characteristics is partially provided between the electron transporting layer having luminous characteristics and the hole transporting layer having luminous characteristics when the electron transporting layer having luminous characteristics emits light.

Claims

1. An organic electroluminescent device having at least a carrier transporting layer and a luminescent layer which use an organic material provided between a hole injection electrode and an electron injection electrode, wherein

a luminescent portion having a luminescent peak wavelength different from a luminescent peak wavelength in said luminescent layer is partially provided in such a manner that it is laminated on the luminescent layer, the luminescent portion and luminescent layer being formed of an electroluminescent organic material that emits light by recombination of charges.

2. The organic electroluminescent device according to claim 1, wherein

said carrier transporting layer is a hole transporting layer,

the hole transporting layer and a luminescent layer having electron transporting characteristics are provided between the hole injection electrode and the electron injection electrode, and

a luminescent portion having a luminescent peak wavelength different from a luminescent peak wavelength in the luminescent layer is partially provided between the luminescent layer and the hole transporting layer in such a manner that it is laminated on the luminescent layer.

3. The organic electroluminescent device according to claim 1, wherein

said carrier transporting layer is an electron transporting layer,

a luminescent layer having hole transporting characteristics and said electron transporting layer are provided between the hole injection electrode and the electron injection electrode, and

a luminescent portion having a luminescent peak wavelength different from a luminescent peak wavelength in the luminescent layer is partially provided between the luminescent layer and the electron transporting layer in such a manner that it is laminated on the luminescent layer.

4. The organic electroluminescent device according to claim 1, wherein

the luminescent peak wavelength in said luminescent portion is longer than the luminescent peak wavelength in the luminescent layer.

5. The organic electroluminescent device according to claim 1, wherein

a plurality of types of luminescent portions having luminescent peak wavelengths which are respectively different from the luminescent peak wavelength in said luminescent layer are partially provided in such a manner that they are respectively laminated on the luminescent layer.

6. An organic electroluminescent device having at least a hole transporting layer having luminous characteristics and an electron transporting layer having luminous characteristics which respectively contain organic materials emitting fluorescence in different colors in a visible region provided between a hole injection electrode and an electron injection electrode, the organic materials emitting light by recombination of charges, wherein

when said hole transporting layer having luminous characteristics emits light, a hole transporting portion having non-luminous characteristics is partially provided between the hole transporting layer having luminous characteristics and said electron transporting layer having luminous characteristics.

7. The organic electroluminescent device according to claim 6, wherein

the same hole transporting material is used for the hole transporting portion having non-luminous characteristics and the hole transporting layer having luminous characteristics, and

a luminescent material is contained in the hole transporting layer having luminous characteristics.

8. An organic electroluminescent device having at least a hole transporting layer having luminous characteristics and an electron transporting layer having luminous characteristics which respectively contain organic materials emitting fluorescence in different colors in a visible region provided between a hole injection electrode and an electron injection electrode, the organic materials emitting light by recombination of charges, wherein

when said electron transporting layer having luminous characteristics emits light, an electron transporting portion having non-luminous characteristics is partially provided between the electron transporting layer having luminous characteristics and said hole transporting layer having luminous characteristics.

9. The organic electroluminescent device according to claim 8, wherein

the same electron transporting material is used for the electron transporting portion having non-luminous characteristics and the electron transporting layer having luminous characteristics, and

a luminescent material is contained in the electron transporting layer having luminous characteristics.

10. An organic electroluminescent device having at least a hole transporting layer having luminous characteristics, a luminescent layer, and an electron transporting layer having luminous characteristics which respectively contain organic materials emitting fluorescence in different colors in a visible region provided between a hole injection electrode and an electron injection electrode, the organic materials emitting light by recombination of charges,

and having at least one of

(a) an electron transporting portion having non-luminous characteristics partially provided between the hole transporting layer having luminous characteristics and the luminescent layer and

(b) a hole transporting portion having non-luminous characteristics partially provided between the luminescent layer and the electron transporting layer having luminous characteristics.