A mixture consisting essentially of 5-40 mol-% of component B and the balance component A, component B consisting essentially of 5-n-propyl-2-(4-cyanophenyl)-1,3 dioxane and component A consisting essentially of 60-70 mol-% of 4-n-butylcyclohexanecarboxylic acid and 30-40 mol-% of 4-n-hexylcyclohexanecarboxylic acid, has superior liquid crystal properties for use in electrooptical devices.