Conjugated polymers are promising emissive materials for display applications due to their solution processability and flexibility. In particular, polymer-based white-emission systems have attracted significant interest because they enable printing-based fabrication and mass production.
In this study, conjugated polymers exhibiting blue–white–yellow emission from solution to solid state were designed, enabling photopatterned emissive structures. Conjugated copolymers were synthesized by incorporating benzoselenadiazole units as long-wavelength-emitting components into a fluorene backbone. As polymer concentration increased, long-wavelength emission was enhanced, leading to a blue-to-yellow shift and white emission at intermediate concentrations. To maintain solution-state emission in thin films, the polymers were dispersed in a transparent polymer matrix and UV-crosslinked at 254 nm. Photopatterning based on these methods was used to realize white-emissive systems.