Organic electroluminescence device

Abstract

The invention relates to the technical field of display, and discloses an organic electroluminescence device. The organic electroluminescence device includes a cathode layer, an electron injection layer, an electron transport layer, a light emitting layer, a hole transport layer, a hole injection layer, and an anode layer, wherein the hole transport layer is made of a heterocyclic hole transport material, and the heterocyclic hole transport material has a general formula shown as follows: a range of an included angle of dihedral angles between two aromatic rings is 0 degree to 90 degrees; symbols used therein have the following meanings: R1, R2 are the same or differently selected from O, S, N; R3, R4 are obstruction groups for performing fine tuning on the dihedral angles; and R5, R6 arethe same or differently selected from aromatic rings, aromatic heterocycles, and alkyl chains. In the organic electroluminescence device, through connection of a group having a larger atomic nucleus at the R3 and the R4, the included angle between the dihedral angles of the aromatic rings is increased, the glass transition temperature thereof is increased, thereby prolonging the life of the organic electroluminescent device, and the heterocyclic hole transport material is less difficult to synthesize molecules, and is low in cost.

Description

technical field [0001] The invention relates to the field of display technology, in particular to an organic electroluminescent device. Background technique [0002] The structure of an OLED device is generally: cathode, electron injection layer, electron transport layer, light-emitting layer, hole transport layer, hole injection layer, anode. The key to improving the performance of the hole transport layer material is to increase its glass transition temperature. Thereby prolonging the life of the device. [0003] At present, in the current technology, there are three ways to increase the glass transition temperature, mainly by increasing the molecular weight of the hole transport layer material or using large non-planar molecules, such as triphenylamine or using intermolecular hydrogen bonds to expand the effective molecular weight of the molecule, but the above Several methods require more complex synthesis to achieve molecular design, making molecular synthesis more dif...

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Problems solved by technology

[0003] At present, in the current technology, there are three ways to increase the glass transition temperature, mainly by increasing the molecular weight of the hole transport layer material or using large non-planar molecules, such as triphenylamine or using intermolecular hydrogen bonds to expand the effective molecular weight of the molecule, but the above Several methods require more complex synthesis to achieve molecular design, making molecular synthesis more difficult and costly

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