A novel liquid crystal compound exhibiting SC phase which, when added to an optically active liquid crystal, makes the resulting chiral smectic liquid crystal material exhibit superior performances in liquid crystal display elements utilizing the ferroelectricity of the material, and a chiral smectic C composition using the compound. The compound is expressed by the formula ##STR1## wherein X represents F or Cl and R.sub.1 and R.sub.2 each represent a straight chain alkyl group of 1 to 18 carbon atoms.
一种新型液晶化合物,展现出SC相,当添加到具有光学活性的液晶中时,使得所得到的手性亚相液晶材料在利用材料的
铁电性质的液晶显示元件中表现出卓越的性能,以及使用该化合物的手性C相组合物。该化合物的
化学式为##STR1## 其中X代表F或Cl,R1和R2各代表1至18个碳原子的直链烷基。