Liquid-crystalline medium and liquid-crystal display comprising the same
The invention relates to a liquid-crystalline medium, preferably having a nematic phase and dielectric anisotropy of 0.5 or more, which comprises one or more compounds of formula YX in which the parameters have the meanings given in the text, to the use thereof in an electro-optical display, particularly in an active-matrix display based on the IPS or FFS effect, to displays of this type which contain a liquid-crystalline medium of this type, and to the use of the compounds of formula YX for the improvement of the transmission and/or response times of a liquid-crystalline medium which comprises one or more additional mesogenic compounds.
1. A liquid-crystalline medium comprising at least one compound of formula YX
in which
denote
independently of each other denote
n denotes 0 or 1,
R Y denotes alkyl, alkoxy, fluorinated alkyl or fluorinated alkoxy having 1 to 7 C atoms, alkenyl, alkenyloxy, alkoxyalkyl or fluorinated alkenyl having 2 to 7 C atoms,
X Y denotes F, Cl, CN, NCS, fluorinated alkyl having 1 to 4 C atoms, fluorinated alkenyl having 2 to 4 C atoms, fluorinated alkoxy having 1 to 4 C atoms or fluorinated alkenyloxy having 2 to 4 C atoms, and
Z Y denotes a single bond, —CH═CH—, —C≡C—, —CH 2 —CH 2 —, —CF 2 —O—, CH 2 —O— or —CO—O—
and at least one compound of formulae II or III:
in which
R 2 denotes alkyl, alkoxy, fluorinated alkyl or fluorinated alkoxy having 1 to 7 C atoms, alkenyl, alkenyloxy, alkoxyalkyl or fluorinated alkenyl having 2 to 7 C atoms,
on each appearance, independently of one another, denote
L 21 and L 22 denote H or F,
X 2 denotes halogen, halogenated alkyl or alkoxy having 1 to 3 C atoms or halogenated alkenyl or alkenyloxy having 2 or 3 C atoms,
m denotes 0, 1, 2 or 3,
R 3 denotes alkyl, alkoxy, fluorinated alkyl or fluorinated alkoxy having 1 to 7 C atoms, alkenyl, alkenyloxy, alkoxyalkyl or fluorinated alkenyl having 2 to 7 C atoms
on each appearance, independently of one another, are
L 31 and L 32 , independently of one another, denote H or F,
X 3 denotes halogen, halogenated alkyl or alkoxy having 1 to 3 C atoms or halogenated alkenyl or alkenyloxy having 2 or 3 C atoms, F, Cl, —OCF 3 , —OCHF 2 , —O—CH 2 CF 3 , —O—CH═CF 2 , —O—CH═CH 2 or —CF 3 ,
Z 3 denotes —CH 2 CH 2 —, —CF 2 CF 2 —, —COO—, trans-CH═CH—, trans-CF═CF—, —CH 2 O— or a single bond, and
n denotes 0, 1, 2 or 3.
2. A liquid-crystalline medium according to claim 1 , comprising at least one compound of formula YX, which is a compound of formulae YX-1, YX-2, YX-3 or YX-4:
in which
R Y denotes alkyl, alkoxy, fluorinated alkyl or fluorinated alkoxy having 1 to 7 C atoms or alkenyl, alkenyloxy, alkoxyalkyl or fluorinated alkenyl having 2 to 7 C atoms, and
X Y denotes F, Cl, CN, NCS, fluorinated alkyl having 1 to 4 C atoms, fluorinated alkenyl having 2 to 4 C atoms, fluorinated alkoxy having 1 to 4 C atoms or fluorinated alkenyloxy having 2 to 4 C atoms.
3. A liquid-crystalline medium according to claim 1 , comprising at least one compound of formulae IV or V:
in which
R 41 and R 42 , independently of one another, have the meaning indicated for R 2 under formula II,
independently of one another and, if
occurs twice,
also these independently of one another, denote
Z 41 and Z 42 , independently of one another and, if Z 41 occurs twice, also these independently of one another, denote —CH 2 CH 2 —, —COO—, trans-CH═CH—, trans-CF═CF—, —CH 2 O—, —CF 2 O—, —C≡C— or a single bond,
p denotes 0, 1 or 2,
R 51 and R 52 , independently of one another, have one of the meanings given for R 41 and R 42
if present, each, independently of one another, denote
Z 51 to Z 53 each, independently of one another, denote —CH 2 —CH 2 —, —CH 2 —O—, —CH═CH—, —C≡C—, —COO— or a single bond, and
i and j each, independently of one another, denote 0 or 1.
4. A liquid-crystalline medium according to claim 3 , comprising at least one compound of formulae VI to IX:
wherein
R 61 denotes an unsubstituted alkyl radical having 1 to 7 C atoms, an unsubstituted alkenyl radical having 2 to 7 C atoms, an unsubstituted alkoxy radical having 1 to 6 C atoms or an unsubstituted alkenyloxy radical having 2 to 6 C atoms,
R 62 denotes an unsubstituted alkyl radical having 1 to 7 C atoms, an unsubstituted alkoxy radical having 1 to 6 C atoms or an unsubstituted alkenyloxy radical having 2 to 6 C atoms, and
l denotes 0 or 1,
R 71 denotes an unsubstituted alkyl radical having 1 to 7 C atoms, or an unsubstituted alkenyl radical having 2 to 7 C atoms,
R 72 denotes an unsubstituted alkyl radical having 1 to 7 C atoms, an unsubstituted alkoxy radical having 1 to 6 C atoms or an unsubstituted alkenyloxy radical having 2 to 6 C atoms,
denotes
R 81 denotes an unsubstituted alkyl radical having 1 to 7 C atoms, or an unsubstituted alkenyl radical having 2 to 7 C atoms,
R 82 denotes an unsubstituted alkyl radical having 1 to 7 C atoms, an unsubstituted alkoxy radical having 1 to 6 C atoms or an unsubstituted alkenyloxy radical having 2 to 6 C atoms,
denotes
Z 8 denotes —(C═O)—O—, —CH 2 —O—, —CF 2 —O— or —CH 2 —CH 2 —,
o denotes 0 or 1,
R 91 and R 92 independently of one another have the meaning given for R 72 above,
denotes
p and q independently of each other denote 0 or 1.
5. A liquid-crystalline medium according to claim 1 , comprising at least one compound of formula I
in which
denotes
denotes
n denotes 0 or 1,
R 11 and R 12 independently of each other denote alkyl, alkoxy, fluorinated alkyl or fluorinated alkoxy having 1 to 7 C atoms, alkenyl, alkenyloxy, alkoxyalkyl or fluorinated alkenyl having 2 to 7 C atoms and R 11 alternatively denotes R 1 and R 12 alternatively denotes X 1 ,
R 1 denotes alkyl, alkoxy, fluorinated alkyl or fluorinated alkoxy, alkenyl, alkenyloxy, alkoxyalkyl or fluorinated alkenyl having 2 to 7 C atoms, and
X 1 denotes F, Cl, fluorinated alkyl, fluorinated alkenyl, fluorinated alkoxy or fluorinated alkenyoxy.
6. A liquid-crystalline medium according to claim 5 , wherein the total concentration of the compounds of formula YX in the medium as a whole is 1% or more to 100% or less.
7. A liquid-crystalline medium according to claim 1 , which additionally comprises one or more chiral compounds.
8. An electro-optical display or electro-optical component, comprising a liquid-crystalline medium according to claim 1 .
9. An electro-optical display according to claim 8 , which is based on the IPS- or FFS mode.
10. An electro-optical display according to claim 8 , which contains an active-matrix addressing device.
11. A method which comprises including a liquid-crystalline medium according to claim 1 in an electro-optical display or in an electro-optical component.
12. An electro-optical display according to claim 8 , which is a mobile display.
13. A process for the preparation of a liquid-crystalline medium according to claim 1 , wherein one or more compounds of formula YX are mixed with one or more mesogenic compounds.
14. A process for the preparation of a compound of formula YX
in which
and
denote
independently of each other denote
n denotes 0 or 1,
R Y denotes alkyl, alkoxy, fluorinated alkyl or fluorinated alkoxy having 1 to 7 C atoms, alkenyl, alkenyloxy, alkoxyalkyl or fluorinated alkenyl having 2 to 7 C atoms,
X Y denotes F, Cl, CN, NCS, fluorinated alkyl having 1 to 4 C atoms, fluorinated alkenyl having 2 to 4 C atoms, fluorinated alkoxy having 1 to 4 C atoms or fluorinated alkenyloxy having 2 to 4 C atoms, and
Z Y denotes a single bond, —CH═CH—, —C≡C—, —CH 2 —CH 2 —, —CF 2 —O—, CH 2 —O— or —CO—O—
except that compounds of formula YX
wherein
n denotes 1,
Z Y denotes a single bond,
denotes
denotes
and
X Y denotes F,
or
n denotes 1,
Z Y denotes a single bond,
denotes
denotes
and
X Y denotes OCF 3 ,
or
n denotes 0,
Z Y denotes a single bond,
denotes
and
X Y denotes F or OCF 3 ,
are excluded
which proceeds via the nucleophilic addition of a metallated aryl derivative to a bicyclohexyl ketone resulting in the corresponding tertiary alcohol, followed by dehydration to give a cyclohexylene-cyclohexenylene-phenylene compound and hydrogenation to a respective bicyclohexylene-phenylene compound.