Novel liquid crystalline compounds having low viscosity, low transition temperatures, positive dielectric anisotropy and extremely low optical birefringence are provided. The compounds are represented by the formula: ##STR1## where R and R.sup.1 can be the same or different straight chain alkyl or alkoxy group and m can be 1 or 2. Guest-host electrooptical displays including a mixture of one or more of the compounds with a suitable pleochroic dye exhibit much improved constrast and low driving voltage while eliminating the need for polarizers and excessive dye additions.
提供具有低粘度、低转变温度、正介电各向异性和极低光学双折射的新型液晶化合物。该化合物由公式表示:##STR1## 其中,R和R.sup.1可以是相同或不同的直链烷基或烷氧基,m可以为1或2。包括一种或多种该化合物与适当的偏光
染料混合物的客体-主体电光显示器具有明显改善的对比度和低驱动电压,同时消除了偏光片和过量
染料添加的需要。