Liquid-crystalline medium comprises one or more substituted dicycohexane compounds (I). Liquid-crystalline medium comprises one or more substituted dicycohexane compounds of formula (I). R1 : 1-15C-alkyl or -alkoxy, where one or more CH 2 groups in the radicals are optionally replaced by -CC-, -CF 2O-, -CH=CH-, divalent group of formula (a) or (b), -O-, -CO-O- or -O-CO- in such a way that O atoms are not linked directly to one another, and one or more H atoms are optionally replaced by halo. Independent claims are included for: (1) preparing the liquid-crystalline medium, comprising mixing (I) with at least one further mesogenic compound and optionally with at least one additive(s) and/or at least one polymerizable compound; and (2) (I). [Image].