We have designed and synthesized six phthalocyanine dyes and one benzoperylene dye for dye-based green Liquid Crystal Display (LCD) color filters. The solubility, spectral properties and thermal stability of the prepared six phthalocyanine dyes varied depending on their isomeric structures and core metals. They were dissolved in industrial solvent–binder composites and spin coated with and without yellow compensating benzoperylene dye into dye-based LCD color filters. The prepared color filters exhibited superior optical properties compared to conventional pigment-based ones due to the fluorescence of benzoperylene dye and less light scattering resulting from the smaller particle size of the dyes. The phthalocyanine dyes substituted at the peripheral (β) positions showed enough thermal stability for color filters and the yellow benzoperylene dye effectively compensated the spectra for vivid green colors.

The color properties of liquid-crystal displays are usually classified on the basis of color representations, contrast ratios, and brightness, which primarily depend on the properties of pigments. Among these classifications, the contrast ratio can be improved by minimizing the light scattering of the pigment particles, which is directly related to the degree of dispersion. Therefore, synergists are usually applied to increase the contrast ratio by augmenting the efficiency of the dispersion. In this study, synergists containing anthraquinone as a backbone were synthesized and then their performance in improving the contrast ratio was examined.

Novel yellow azo pyridone dye derivatives were synthesized for use in image-sensor color filters. The synthesized compounds have a basic chemical structure composed of azo, hydroxy, amide, and nitrile groups as well as different halide groups. New materials were evaluated on the basis of their optical, thermal, and surface properties under conditions mimicking those of a commercial device fabrication process. A comparison of their related performance revealed that, among the four prepared compounds, 5-((4,6-dichlorocyclohexa-2,4-dien-1-yl)diazenyl)-6-hydroxy-1,4-dimethyl-2-oxo-1,2-dihydropyridine-3-carbonitrile (Cl-PAMOPC) exhibited the best performance as an image-sensor color filter material, including a solubility greater than 0.1 wt% in propylene glycol monomethyl ether acetate solvent, a high decomposition temperature of 263 °C, and stable color difference values of 4.93 and 3.88 after a thermal treatment and a solvent-resistance test, respectively. The results suggest that Cl-PAMOPC can be used as a green dye additive in an image-sensor colorant.