| abstract |
An MLC display having no or only a small degree of disadvantages of the prior art, preferably having at the same time a very high resistivity and a low threshold voltage, and in particular ECB, Suitable as a component of liquid crystal media for VA, CSH, DAP and IPS displays, A novel stable liquid crystal or a mesophase-forming compound having a negative DC anisotropy is provided. The present invention relates to a compound of the formula I Wherein R 1 , R 2 , A 1 , A 2 , A 3 , A 4 , Z 1 , Z 2 and Z 3 are as defined in claim 1, a novel tetracyclic compound with negative DC anisotropy represented by They relate to their use as components of liquid-crystalline media and to liquid-crystal and electro-optical display elements comprising the liquid-crystalline media according to the invention. |