1,8-Difluorisochinolinderivate und ihre Verwendung in flüssigkristallinen Mischungen

摘要

The invention concerns 1,8-difluorisoquinoline derivatives of the formula (I) R<1>(-M<1>)a(-A<1>-M<2>)b(-A<2>-M<3>)c-B(-M<4>-A<3>)d(-M<5>-A<4>)e(-M< 6>)f-R<2>, in which the symbols and indices have the following meanings: group B is R<1>, R<2> are, for example, alkyl groups with 1-20 C atoms; M<1>, M<2>, M<3>, M<4>, M<5> and M<6> are, for example, -O-, CO-O-, -O-CO- or a single bond; A<1>, A<2>, A<3> and A<4> are, for example, 1,4-phenylene, pyrimidine-2,5-diyl or trans-1,4-cyclohexylene; and a, b, c, d, e and f are 0 or 1, a condition being that the sum of b, c, d and e is 0, 1 or 2. Compounds of formula (I) in the pure state are colourless and as a rule form liquid crystalline mesophases in a temperature range favourable to electro-optical applications. The compounds are chemically and thermally stable and light stable.