Liquid crystalline biphenyls

A nematic composition which comprises a compound of the formula ##STR14## wherein R is straight-chain alkyl of 3 to 8 carbon atoms or straight-chain alkoxy of 3 to 10 carbon atoms, or mixtures thereof, and one or more compounds of the formula ##STR15## wherein R.sub.1 is straight-chain alkyl of 2 to 8 carbon atoms, straight-chain alkoxy of 4 to 7 carbon atoms, straight-chain alkanoyloxy of 2 to 8 carbon atoms or straight-chain alkylcarbonate of 2 to 11 carbon atoms.

A nematic composition which comprises a compound of the formula ##STR16## wherein R is straight-chain alkyl of 3 to 8 carbon atoms or straight-chain alkoxy of 3 to 10 carbon atoms, or mixtures thereof, and one or more compounds of the formula ##STR17## wherein R.sub.2 is straight-chain alkyl of 4 to 7 carbon atoms or straight-chain alkylcarbonate of 2 to 12 carbon atoms.

A nematic composition which comprises a compound of the formula ##STR18## wherein R is straight-chain alkyl of 3 to 8 carbon atoms or straight-chain alkoxy of 3 to 10 carbon atoms, or mixtures thereof, and one or more compounds of the formula ##STR19## wherein R.sub.3 is straight-chain alkyl of 4 to 8 carbon atoms, straight-chain alkoxy of 5 to 8 carbon atoms or straight-chain alkylcarbonate of 3 to 11 carbon atoms.

A nematic composition which comprises a compound of the formula ##STR20## wherein R is straight-chain alkoxy of 3 to 10 carbon atoms, or mixtures thereof, and one or more compounds of the formula ##STR21## wherein R.sub.4 is straight-chain alkyl or straight-chain alkoxy.

An electro-optical cell containing a dielectric which consists essentially of a nematic compound of the formula ##STR22## wherein R is straight-chain alkoxy of 3 to 10 carbon atoms, or mixtures thereof.