This paper presents a novel approach to achieving highly efficient electroluminescence (EL) in organic light-emitting diodes (OLEDs) through the concept of "Hyper-fluorescence." The authors designed a series of advanced electroluminescent (EL) molecules composed of conventional CHN atoms without any precious metals. By minimizing the energy gap between the singlet (S₁) and triplet (T₁) excited states, they achieved efficient spin-up conversion from T₁ to S₁ states while maintaining a high radiative decay rate, resulting in a fluorescence efficiency of over 90%. Using these molecules, they realized an external EL efficiency of over 19%, comparable to high-efficiency phosphorescence-based OLEDs. The key to this efficiency lies in the design of the molecules to achieve a small ΔE_ST (energy gap between S₁ and T₁ states), which enhances the reverse intersystem crossing (ISC) process. The molecules are based on carbazolyl dicyanobenzene (CDCB), where the steric hindrance between the donor and acceptor moieties leads to a well-localized HOMO and LUMO, reducing the energy gap. This design allows for both high photoluminescence (PL) efficiency and a wide range of emission colors. The authors synthesized CDCBs through a one-step reaction, demonstrating cost advantages and high yields. They characterized the materials using various techniques, including NMR, IR, HR-MS, and elemental analysis. The CDCBs showed high thermal stability and exhibited efficient thermally-activated delayed fluorescence (TADF) with high PL quantum yields. The temperature dependence of the PL decay curves confirmed the TADF mechanism, with the delayed component monotonically decreasing at lower temperatures due to the rate-determining reverse ISC process. In OLEDs, the CDCB derivatives were used as emitters, and the devices demonstrated high external EL quantum efficiencies, with the green OLED achieving 19.3±1.5%, the orange OLED achieving 11.2±1%, and the sky-blue OLED achieving 8.0±1%. These results highlight the potential of TADF materials for advanced OLED applications, opening new avenues for solid-state lighting and display technologies.This paper presents a novel approach to achieving highly efficient electroluminescence (EL) in organic light-emitting diodes (OLEDs) through the concept of "Hyper-fluorescence." The authors designed a series of advanced electroluminescent (EL) molecules composed of conventional CHN atoms without any precious metals. By minimizing the energy gap between the singlet (S₁) and triplet (T₁) excited states, they achieved efficient spin-up conversion from T₁ to S₁ states while maintaining a high radiative decay rate, resulting in a fluorescence efficiency of over 90%. Using these molecules, they realized an external EL efficiency of over 19%, comparable to high-efficiency phosphorescence-based OLEDs. The key to this efficiency lies in the design of the molecules to achieve a small ΔE_ST (energy gap between S₁ and T₁ states), which enhances the reverse intersystem crossing (ISC) process. The molecules are based on carbazolyl dicyanobenzene (CDCB), where the steric hindrance between the donor and acceptor moieties leads to a well-localized HOMO and LUMO, reducing the energy gap. This design allows for both high photoluminescence (PL) efficiency and a wide range of emission colors. The authors synthesized CDCBs through a one-step reaction, demonstrating cost advantages and high yields. They characterized the materials using various techniques, including NMR, IR, HR-MS, and elemental analysis. The CDCBs showed high thermal stability and exhibited efficient thermally-activated delayed fluorescence (TADF) with high PL quantum yields. The temperature dependence of the PL decay curves confirmed the TADF mechanism, with the delayed component monotonically decreasing at lower temperatures due to the rate-determining reverse ISC process. In OLEDs, the CDCB derivatives were used as emitters, and the devices demonstrated high external EL quantum efficiencies, with the green OLED achieving 19.3±1.5%, the orange OLED achieving 11.2±1%, and the sky-blue OLED achieving 8.0±1%. These results highlight the potential of TADF materials for advanced OLED applications, opening new avenues for solid-state lighting and display technologies.