Abstract: The invention relates to liquid crystal nematic substances based on new derivatives of 1,3-dioxanes in electro-optical components, which are used, for instance, as displays in electronic clocks and computer systems.The subject of the invention is nematic liquid crystal substances with favorable properties concerning melting and clear temperatures, stability against thermal stress and electrical fields, low viscosity and low threshold voltage.It was found that liquid crystal 2,5-di-substituted cyclohexyl derivatives of 1,3 dioxanes, having the general formula ##STR1## R.sup.1 =C.sub.n H.sub.2n+1 ; C.sub.n H.sub.2n+1 O; C.sub.n H.sub.2n+1 COO; CN; NO.sub.2 ; F; Cl; Brand R.sup.2 =C.sub.n H.sub.2n+1 with n+1 to 9are suitable for use in electro-optical components.