Polycyclic Compound Emission Layer for OLED Driving Voltage and Lifetime

The patent modifies the molecular structure of emission layer materials by introducing specific polycyclic aromatic hydrocarbon groups with controlled ring-forming carbon atom counts (12-25 atoms) and varying heteroatom compositions (N, O, S, Se). These structural parameter changes optimize triplet energy levels and HOMO/LUMO energy gaps, simultaneously achieving lower driving voltages and extended device lifetimes through improved charge transport and reduced degradation pathways

The patent employs composite material strategies by combining polycyclic aromatic hydrocarbon groups with various heteroatom-containing substituents (R1-R7 groups including aryl, heteroaryl, alkyl, and functional groups). This creates composite molecular structures that integrate the stability of polycyclic cores with the electronic properties of heteroatom substituents, achieving synergistic effects that improve both efficiency and lifetime while maintaining low driving voltage characteristics

The patent applies local quality by positioning specific functional groups (heteroatoms N, O, S, Se and their substituents R5-R7) at particular locations within the polycyclic aromatic hydrocarbon structure. This localized functionalization allows precise control over triplet energy levels and emission properties at specific molecular sites while maintaining the overall stability of the polycyclic core, achieving high emission efficiency without excessive molecular complexity

The patent segments the emission layer material into distinct functional modules: a stable polycyclic aromatic hydrocarbon core (L group with 12-25 ring-forming carbons) and variable heteroatom-containing substituents (R1-R7 groups). This segmentation allows independent optimization of the core for stability and the substituents for energy level tuning, simplifying material design while achieving complex performance targets including optimized triplet energy levels and high emission efficiency