Fused Ring Organic Compound for Low Voltage EL Devices

The patent applies parameter changes by modifying the molecular structure of organic compounds used in the emitting layer and electron transporting zone. Specifically, it introduces compounds with fused ring structures (4 or more fused rings with 22 or less ring atoms) and specific substituent groups that alter the electronic properties, HOMO-LUMO energy levels, and charge transport characteristics of the material, thereby reducing drive voltage and improving luminous efficiency

The patent employs composite materials by combining specific aromatic hydrocarbon groups with heterocyclic groups containing electron-donating or electron-withdrawing substituents. This creates novel organic compounds that integrate multiple functional groups (e.g., triphenylamine, carbazole, pyridine, pyrimidine rings) to achieve both low drive voltage and high luminous efficiency simultaneously

The patent improves luminous efficiency by changing molecular parameters including introducing fused ring structures to enhance rigidity and planarity, adding electron-donating groups (alkyl, alkoxy, amino) to raise HOMO levels, and incorporating electron-withdrawing groups (cyano, carbonyl, nitro) to adjust LUMO levels, thereby optimizing charge injection and recombination processes

The patent applies local quality by placing specific functional groups at particular positions within the molecular structure. For example, electron-donating groups are positioned to enhance hole injection at the anode interface, while electron-withdrawing groups are placed to facilitate electron injection at the cathode interface, creating localized functional zones within the compound