Synthesis and Characterization of Hybrid Azo Colorants for LCD Color Filter

LCD Color Filter용 Hybrid Azo Colorants 합성 및 특성 연구

  • Choi, Woo-Geun (Department of Image Science & Engineering, Pukyong National University) ;
  • Jeong, Yeon Tae (Department of Image Science & Engineering, Pukyong National University)
  • 최우근 (부경대학교 이미지시스템공학과) ;
  • 정연태 (부경대학교 이미지시스템공학과)
  • Received : 2013.06.10
  • Accepted : 2013.06.17
  • Published : 2013.07.01


We focused on the development of red azo colorants with high thermal stability and good solubility for LCD color filter in this research. For the synthesis of hybrid azo colorants, we used the couplers of aniline, naphthol and benzoimidazol functional group. The synthesized hybrid azo colorants were charaterized by using NMR, UV/visible spectroscopy, FT-IR, EA and TGA. They represented the maximum absorption wavelengths which are longer than 500 nm in UV/visible spectrum. So they were confirmed to be suitable for red colorants of LCD color filter. Azo compound (1a, 1b) with aniline functional group had good solubility in organic solvents such as acetone, methanol, chloroform and PGMEA. Moreover azo compounds (1c, 1d and 1e) with naphthol and benzoimidazolone functional group gave excellent thermal stability higher than $250^{\circ}C$ in TGA thermograms.


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