Development of negative /spl Delta//spl epsiv/ LC materials

Recently the LCD market has shown significant growth from simple TN applications to displays with high information content such as in notebook computers. In order to understand trends in LC materials, this paper reviews the development of negative /spl Delta//spl epsiv/ LC materials. While compounds having a 2,3-dicyanophenyl group in the molecular structure have a large negative /spl Delta//spl epsiv/, they have a disadvantage of having high viscosity and insufficient photostability. Pyridazine derivatives exhibit lower viscosity but are not photostable. The difluorophenyl derivatives have been developed. These materials are characterized by high negative /spl Delta//spl epsiv/ values and viscosity. These compound classes are promising materials for liquid crystal mixtures for various applications as ECB, VA TFT liquid crystal display.