| abstract |
The present invention relates to a dibenzofuran and a dibenzothiophene derivative having the formula I,nâ–ˇnWherein X1, X2, W, Y, R, A, Z and m have the meanings as defined in claim 1 of the patent application; the preparation method thereof; the use as a component in a liquid crystal medium; and the liquid crystal according to the invention An electro-optic display element of the medium. |