CN-117979728-B - Organic electroluminescent blue light emitting device, display panel and display device

CN117979728BCN 117979728 BCN117979728 BCN 117979728BCN-117979728-B

Abstract

The invention discloses an organic electroluminescent blue light emitting device, a display panel and a display device, and belongs to the technical field of display. The organic electroluminescent blue light emitting device comprises an anode, a hole transmission unit, a light emitting unit, an electron transmission unit and a cathode which are sequentially arranged in a stacked mode, wherein the light emitting unit comprises a blue fluorescent light emitting layer, a separation layer and a blue phosphorescent light emitting layer, one of the blue fluorescent light emitting layer and the phosphorescent light emitting layer is close to the hole transmission unit, the other of the blue fluorescent light emitting layer and the phosphorescent light emitting layer is close to the electron transmission unit, the blue fluorescent light emitting layer comprises a blue fluorescent host material and a blue fluorescent guest material, the half-width of an emission spectrum of the blue fluorescent guest material is 20-30 nm, the blue phosphorescent light emitting layer comprises a blue phosphorescent host material and a blue phosphorescent guest material, the half-width of an emission spectrum of the blue phosphorescent guest material is 40-60 nm, and the half-width difference value between the blue phosphorescent light emitting material and the fluorescent guest material is 20-40 nm. The device can reduce blue light color deviation and improve color deviation under different visual angles.

Inventors

CHEN LEI
LI JUNCONG
ZHANG DONGXU
QIU LIXIA

Assignees

京东方科技集团股份有限公司

Dates

Publication Date: 20260508
Application Date: 20240318

Claims (10)

1. The organic electroluminescent blue light emitting device is characterized by comprising an anode, a hole transmission unit, a light emitting unit, an electron transmission unit and a cathode which are sequentially stacked, wherein the light emitting unit comprises a blue fluorescent light emitting layer, an interlayer and a blue phosphorescent light emitting layer which are sequentially stacked, the blue fluorescent light emitting layer is close to the hole transmission unit, and the blue phosphorescent light emitting layer is close to the electron transmission unit; The blue fluorescent light-emitting layer comprises a blue fluorescent host material and a blue fluorescent guest material, the half-width of the emission spectrum of the blue fluorescent guest material is 20-30 nm, and the blue fluorescent host material is an N-type material; The blue phosphorescent light-emitting layer comprises a blue phosphorescent host material and a blue phosphorescent guest material, the half-width of the emission spectrum of the blue phosphorescent guest material is 40-60 nm, and the blue phosphorescent host material comprises an N-type material and a P-type material; the difference between the half-width of the emission spectrum of the blue phosphorescent guest material and the half-width of the emission spectrum of the blue fluorescent guest material is 20 nm-40 nm; The spacer layer includes a layer of electron transporting material.
2. The organic electroluminescent blue light-emitting device according to claim 1, wherein the blue fluorescent guest material has a chemical structural formula as follows: a is directly connected with a B-N six-membered heterocycle, wherein A is substituted or unsubstituted aryl or cycloalkyl of C6-C60, condensed aryl of C10-C60, or five-membered or six-membered aromatic heterocyclic group of C2-C60; r1, R2, R3, R4 are each independently hydrogen, heavy hydrogen, halogen, nitro, nitrile, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C1-C30 thioether, substituted or unsubstituted C6-C50 aryl, or C2-C50 heteroaryl formed from a substituted or unsubstituted C2-C9 ring structure, substituted or unsubstituted C6-C30 cycloalkyl.
3. The organic electroluminescent blue light-emitting device according to claim 1, wherein the blue phosphorescent guest material is an iridium complex or a platinum complex.
4. The organic electroluminescent blue light-emitting device according to claim 1, wherein the material of the interlayer is a benzimidazole derivative, an imidazopyridine derivative, a benzimidazolofilidine derivative, a pyrimidine derivative, a triazine derivative, a quinoline derivative, an isoquinoline derivative, or a phenanthroline derivative.
5. The organic electroluminescent blue light emitting device according to claim 4, wherein the hole transport unit comprises at least one of a hole injection layer, a hole transport layer, and an electron blocking layer; The electron transport unit includes at least one of an electron injection layer, an electron transport layer, and a hole blocking layer.
6. A display panel, comprising a red sub-pixel, a green sub-pixel and a blue sub-pixel, wherein each sub-pixel comprises an anode, a hole transport unit, a light emitting layer, an electron transport unit and a cathode which are sequentially stacked; wherein the blue subpixel employs the organic electroluminescent blue light emitting device of any one of claims 1 to 5.
7. The display panel of claim 6, wherein the red light emitting layer of the red subpixel comprises a red phosphorescent host material and a red phosphorescent guest material, and the green light emitting layer of the green subpixel comprises a green phosphorescent host material and a green phosphorescent guest material; the half-width difference of the light emission spectra of the green phosphorescent guest material and the red phosphorescent guest material is less than 45nm; The half-width difference of the luminescence spectrum of the green phosphorescent guest material and the blue phosphorescent guest material is less than 35nm; The difference of half-width of the light emission spectrum of the blue phosphorescent guest material and the red phosphorescent guest material is less than 45nm.
8. The display panel of claim 7, wherein at least one of the red phosphorescent guest material, the green phosphorescent guest material, and the blue phosphorescent guest material is a platinum complex.
9. The display panel according to any one of claims 6-8, further comprising a light extraction layer arranged layer upon layer at a surface of the cathode facing away from the electron transport unit.
10. A display device, characterized in that the display device comprises a display panel according to any one of claims 6-9.

Description

Organic electroluminescent blue light emitting device, display panel and display device Technical Field The invention relates to the technical field of display, in particular to an organic electroluminescent blue light emitting device, a display panel and a display device. Background An Organic LIGHT EMITTING Diode (OLED) display panel adopts three primary colors to realize color display, and includes a red sub-pixel, a green sub-pixel and a blue sub-pixel, which respectively emit red light R, green light G and blue light B and mix according to a certain brightness ratio, thereby synthesizing light of different colors. Along with the change of the visual angle, the colors of the lights emitted by different sub-pixels also change along with the change of the visual angle, particularly, the color change amplitude of the blue light emitted by the blue sub-pixel is obviously larger than the color change amplitude of the red light and the green light, and the color shift is large, so that the blue light is excessively shifted in a certain visual angle range to cause unbalance of a white picture. Disclosure of Invention In view of the above, the present invention provides an organic electroluminescent blue light emitting device, a display panel, and a display apparatus, which can solve the technical problems existing in the related art. Specifically, the method comprises the following technical scheme: in one aspect, an organic electroluminescent blue light emitting device is provided, the organic electroluminescent blue light emitting device comprising an anode, a hole transporting unit, a light emitting unit, an electron transporting unit, and a cathode, which are sequentially stacked; The light-emitting unit comprises a blue fluorescent light-emitting layer, an interlayer and a blue phosphorescent light-emitting layer which are sequentially stacked, wherein one of the blue fluorescent light-emitting layer and the blue phosphorescent light-emitting layer is close to the hole transmission unit, and the other of the blue fluorescent light-emitting layer and the blue phosphorescent light-emitting layer is close to the electron transmission unit; the blue fluorescent light-emitting layer comprises a blue fluorescent host material and a blue fluorescent guest material, and the half-width of the emission spectrum of the blue fluorescent guest material is 20-30 nm; the blue phosphorescent light-emitting layer comprises a blue phosphorescent host material and a blue phosphorescent guest material, and the half-width of the emission spectrum of the blue phosphorescent guest material is 40-60 nm; the difference between the half-width of the emission spectrum of the blue phosphorescent guest material and the half-width of the emission spectrum of the blue fluorescent guest material is 20 nm-40 nm. In some possible implementations, the chemical structural formula of the blue fluorescent guest material is as follows: a is directly connected with a B-N six-membered heterocycle, wherein A is substituted or unsubstituted aryl or cycloalkyl of C6-C60, condensed aryl of C10-C60, or five-membered or six-membered aromatic heterocyclic group of C2-C60; r1, R2, R3, R4 are each independently hydrogen, heavy hydrogen, halogen, nitro, nitrile, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C1-C30 thioether, substituted or unsubstituted C6-C50 aryl, or C2-C50 heteroaryl formed from a substituted or unsubstituted C2-C9 ring structure, substituted or unsubstituted C6-C30 cycloalkyl. In some possible implementations, the blue phosphorescent guest material is an iridium complex or a platinum complex. In some possible implementations, the barrier layer includes a layer of electron transporting material. In some possible implementations, the material of the interlayer is a benzimidazole derivative, an imidazopyridine derivative, a benzimidazolofilidine derivative, a pyrimidine derivative, a triazine derivative, a quinoline derivative, an isoquinoline derivative, or a phenanthroline derivative. In some possible implementations, the hole transport unit includes at least one of a hole injection layer, a hole transport layer, and an electron blocking layer; The electron transport unit includes at least one of an electron injection layer, an electron transport layer, and a hole blocking layer. In another aspect, there is provided a display panel including red, green, and blue sub-pixels, each sub-pixel including an anode, a hole transporting unit, a light emitting layer, an electron transporting unit, and a cathode, which are sequentially stacked; Wherein the blue sub-pixel adopts any one of the organic electroluminescent blue light emitting devices. In some possible implementations, the red light emitting layer of the red subpixel includes a red phosphorescent host material and a red phosphorescent guest material, and the green light e