Liquid crystal medium
View Patent ↗Liquid crystal media based on a mixture of polar compounds of formulae I-VIII, their use for electro-optical purposes, and displays containing this medium, are described.
1. A liquid crystal medium comprising, by weight:
15 to 25% of one or more compounds of formula I,
5 to 15% of one or more compounds of formula II,
1 to 10% of one or more compounds of formula III,
1 to 8% of one or more compounds of formula IV,
5 to 15% of one or more compounds of formula V,
20 to 30% of one or more compounds of formula VI,
20 to 30% of one or more compounds of formula VII,
3 to 10% of one or more compounds of formula VIII,
in which
R 1 and R 5 are independently of each other methyl, ethyl, n-propyl, n-butyl, n-pentyl or n-hexyl,
R 2 is methoxy, ethoxy, n-propoxy, n-butoxy or n-pentoxy,
R 3 is vinyl or 1E-propenyl,
R 4 is vinyl or 3-butenyl.
2. A liquid crystal medium according to claim 1 , which comprises the following compounds
3. A liquid crystal medium according to claim 2 , comprising, by weight
6 to 10% of compounds of formula Ia,
6 to 10% of compounds of formula Ib,
2 to 5% of compounds of formula Ic,
6 to 10% of compounds of formula IIa,
2 to 5% of compounds of formula IIIa,
2 to 4% of compounds of formula IVa,
8 to 12% of compounds of formula Va,
12 to 17% of compounds of formula VIa,
8 to 12% of compounds of formula VIb,
11 to 15% of compounds of formula VIIa,
11 to 15% of compounds of formula VIIb,
2 to 4% of compounds of formula VIIIa,
2 to 4% of compounds of formula VIIIb.
4. An electro-optical liquid crystal display containing a liquid crystal medium according to claim 1 .
5. An electro-optical liquid crystal display containing a liquid crystal medium according to claim 2 .
6. An electro-optical liquid crystal display containing a liquid crystal medium according to claim 3 .
7. A liquid crystal medium of claim 1 , further comprising up to 15% by weight of pleochroic dyes, stabilizers and/or chiral dopants.