Aryloxy- and chloro-substituted zinc(II) phthalocyanine dyes: Synthesis, characterization, and application for reducing the thickness of color filters

Abstract

In the development of display devices, a color filter is still considered an indispensable component. For a thinner display panel, the thickness of the color filter also needs to be decreased. However, if the thickness of the color filter is reduced, the color properties, including the color purity and color gamut are simultaneously diminished. Therefore, introduction of new colorants is needed to lower the thickness without diminishing the color performance. In this study, four phthalocyanine green dyes were synthesized for use in color filters. The molecular geometry and absorption properties were predicted by density functional theory (DFT) and time-dependent DFT, and UV-Vis spectroscopy was employed to measure the optical properties. The thermal stabilities of the dyes were examined by thermogravimetric analysis. A dye with suitable solubility and color properties was adopted in the color filter, and the optical properties and thickness of the dye-based color filter were compared to those of the pigment-based color filter. The chromatic performance and thickness of the color filter were determined by color spectrometry and Alpha step, respectively. Finally, we confirmed that the dye could enable the decrease in the thickness of the filter and provide a superior color property.