Synthesis and characterization of some perylene dyes for dye-based LCD color filters

Eight red perylene dyes were synthesized to improve the optical performance of LCD color filters. Among them, dyes with bulky functional substituents at the bay and terminal positions were highly soluble in cyclohexanone, the industrial solvent currently used in the pigment dispersion method. The spectral properties and thermal stability of the dye-based color filters with these dyes were examined by comparing them with pigment-based ones. The prepared color filters exhibited superior spectral properties due to the smaller particle size of the dyes, which led to less light scattering. However, their thermal stability varied with the dye structures, and only the dyes mono-substituted at the bay position had sufficient thermal stability.