25‐2: Eco‐friendly NMP Free Polyimide for AMOLED Display Substrate

NMP (N‐Methyl‐2‐Pyrrolidone) is a liquid material at room temperature and is widely used in PI (Polyimide) solvent material, PR stripper, and mask cleaning required for OLED manufacturing process. However, the issue of reproductive toxicity disease has been raised in the field of ESG management and environmental safety, and it is necessary to develop materials and processes to replace NMP in the near future. In this study, we developed DMPA (N,N‐Dimethylpropionamide) cosolvent as an eco‐friendly solvent that does not contain NMP in the PI solution for OLED flexible substrate material. The properties of DMPA (N,N‐Dimethylpropionamide) cosolvent PI have similar results of the conventional NMP PI. We applied this new PI to the OLED backplane panel and resulted in reliable low‐temperature polysilicon (LTPS) TFT characteristics with robust OLED panel. It is very meaningful that we developed the world's first eco‐friendly OLED flexible substrate material and panel.