Claims
- 1. A liquid-crystalline medium comprising one or more compounds of the formula I ##STR79## in which R is H or an alkyl, oxaalkyl or oxaalkenyl radical having 1-6 carbon atoms, alkyl optionally having a --CH.sub.2 -- group replaced by --CH=CH--,
- X is F, Cl, CN or an alkyl, alkoxy, alkenyloxy or alkenyl radical having 1 to 6 carbon atoms which is substituted by one or more fluorine atoms,
- L.sup.1 is F,
- L.sup.2 is H or F,
- L.sup.3 is H,
- Z is --CH.sub.2 CH.sub.2 --, --CH=CH--, or --C.ident.C-- [or a single bond], and
- n is 0, 1, 2 or 3.
- 2. A liquid-crystalline medium according to claim 1, wherein X is F, Cl, CN, CF.sub.3, OCHF.sub.2, OCF.sub.3 or OCHFCF.sub.3.
- 3. A liquid-crystalline medium according to claim 1, further comprising one or more compounds selected from the group consisting of those of the formulae II, III and IV ##STR80## in which R.sup.1 is alkyl, oxaalkyl, fluoroalkyl or alkenyl, each having 1 to 7 carbon atoms,
- X.sup.1 is F, Cl, CF.sub.3, OCF.sub.3 or OCHF.sub.2,
- Y.sup.1 and Y.sup.2 are each, independently of the other, H or F, and
- r is 0 or 1.
- 4. The medium of claim 1, wherein in formula I, X is a radical containing not more than 3 carbon atoms.
- 5. The medium of claim 1, wherein in formula I, n is 0 or 1.
- 6. The medium of claim 1, wherein in formula I, R is H or methyl.
- 7. The medium of claim 1, wherein the medium comprises 1 to 40% by weight of compounds of the formula I.
- 8. The medium of claim 1, wherein the medium comprises 5 to 30% by weight of compounds of the formula I.
- 9. The medium of claim 1, wherein the medium comprises more than 40% by weight of compounds of the formula I.
- 10. The medium of claim 1, wherein the medium comprises 45 to 90% by weight of compounds of the formula I.
- 11. The medium of claim 1, wherein the medium comprises three, four or five different compounds of the formula I.
- 12. The medium of claim 3, wherein the medium comprises at least 50% by weight of compounds of the formulae I to IV.
- 13. The medium of claim 3, wherein the medium consists essentially of compounds of the formulae I to IV.
Priority Claims (1)
Number |
Date |
Country |
Kind |
195 15 504 |
Apr 1995 |
DEX |
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Parent Case Info
This is a divisional of application Ser. No. 08/639,975 filed Apr. 29, 1996, U.S. Pat. No. 5,807,500.
US Referenced Citations (8)
Foreign Referenced Citations (2)
Number |
Date |
Country |
390395 |
Oct 1990 |
EPX |
9302152 |
Feb 1993 |
WOX |
Non-Patent Literature Citations (1)
Entry |
Abstract of WO 91/08184 (1991). |
Divisions (1)
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Number |
Date |
Country |
Parent |
639975 |
Apr 1996 |
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