Liquid-crystalline media

Patent metadata

Field	Value
Publication number	US-10072209-B2
Application number	US-201213721203-A
Country	US
Kind code	B2
Filing date	Dec 20, 2012
Priority date	Dec 20, 2011
Publication date	Sep 11, 2018
Grant date	Sep 11, 2018

Abstract

The invention relates to liquid-crystalline media which can be used, in particular, for electro-optical displays having active-matrix addressing based on the ECB effect and for IPS (in-plane switching) displays or FFS (fringe field switching) displays.

First claim

What is claimed is:

1. A liquid-crystalline medium having a nematic phase comprising:
at least two compounds of the formula I,

in which R 1 and R 1* each, independently of one another, denote an alkyl or alkoxy radical having 1 to 15 C atoms, where, in addition, one or more CH 2 groups in these radicals may each be replaced, independently of one another, by —C≡C-, —CF 2 O-, —CH═CH—,

—O—, —CO—O—, —O—CO— in such a way that O atoms are not linked directly to one another, and in which, in addition, one or more H atoms may be replaced by halogen,
Z 1 denotes a single bond, —CH 2 CH 2 -, —CH═CH—, —CH 2 O—, —OCH 2 -, -CF 2 O—, —OCF 2 -, —COO—, —OCO—, —C 2 F 4 -, -CF═CF—, or —CH═CHCHO—,
L 1 and L 2 each, independently of one another, denote F, Cl, CF 3 , OCF 3 , or CHF 2 ;
a compound of the formula,

in which n=3; and
at least one compound of the formula O-16,

in which R 1 and R 2 each, Independently of one another, denote H, an alkyl radical having up to 15 C atoms which is unsubstituted, monosubstituted by CN or CF 3 , or at least monosubstituted by halogen, and wherein, in addition, one or more CH 2 groups in the alkyl radical may be replaced by —O—, —S—,

—C≡C—, —CF 2 O—, —OCF 2 -, —OC—O—, or —O—CO— in such a way that O atoms are not linked directly to one another.

2. A liquid-crystalline medium according to claim 1 , wherein the proportion of the compounds in the medium as a whole is 5-65% by weight.

3. A liquid-crystalline medium according to claim 1 further comprising one or more compounds of the formula III,

in which
R 31 and R 32 each, independently of one another, denote a straight-chain alkyl, alkoxyalkyl or alkoxy radical having up to 12 C atoms, and

 denotes

Z 3 denotes a single bond, —CH 2 CH 2 -, —CH═CH—, —CF 2 O—, —OCF 2 -, —OCH 2 O-, —OCH 2 —, —COO—, —OCO—, —C 2 F 4 -, -C 4 H 8 -, -CF═CF—.

4. A liquid-crystalline medium according to claim 1 further comprising one or more compounds of the formula L-1 to L-11,

in which
R, R 1 and R 2 each, independently of one another, denote H, an alkyl radical having up to 15 carbon atoms, which is unsubstituted, mono-substituted by CN or CF 3 or at least mono-substituted by halogen, and one or more CH 2 groups in these radicals may be replaced —O—,—S—,

 —C—, —CF 2 O—, —OCF 2 —, —OC—O—or —O—CO— in such a way that oxygen atoms are not linked directly to on another, and alkyl denotes an alkyl radical having 1-6 C atoms, and
s denotes 1 or 2.

5. A liquid-crystalline medium according to claim 1 further comprising one or more terphenyls of the formulae T-1 to T-21,

in which
R denotes a straight-chain alkyl or alkoxy radical having 1-7 C atoms, and
m denotes 1-6.

6. A liquid-crystalline medium according to claim 1 further comprising one or more compounds of the formulae O-1 to O-17,

in which
R 1 and R 2 each, independently of one another, denote H, an alkyl radical having up to 15 C atoms which is unsubstituted, monosubstituted by CN or CF 3 or at least monosubstituted by halogen, where, in addition, one or more CH 2 groups in these radicals may be replaced by —O—, —S—,

 —≡C—, —CF 2 O—, —OCF 2 —, —OC—O— or —O—CO— in such a way that O atoms are not linked directly to one another.

7. A liquid-crystalline medium according to claim 1 further comprising one or more indane compounds of the formula In,

in which
R 11 , R 12 , R 13 denote a straight-chain alkyl, alkoxy, alkoxyalkyl or alkenyl radical having 1-5 C atoms,
R 12 and R 13 additionally also denote halogen,

 denotes

denotes 0, 1 or 2.

8. A liquid-crystalline medium according to claim 1 further comprising one or more indane compounds of the formula P4

in which
R 1 denotes an alkyl or alkoxy radical having 1 to 15 C atoms, where, in addition, one or more CH 2 groups in these radicals may each be replaced independently of one another, by —C≡C—, —CF 2 O—, —CH═CH—,

 —CO—O—, —O—CO— in such a way that O atoms are not linked directly to one another, and in which, in addition, one or more H atoms may be replaced by halogen.

9. A process for the preparation of a liquid-crystalline medium according to claim 1 , wherein at least one compound of the formula I is mixed with at least one further liquid-crystalline compound, and one or more additives are optionally added.

10. A process according to claim 9 , wherein the additive is selected from the group consisting of stabilisers, antioxidants, UV absorbers, nanoparticles, microparticles, polymerisable compounds, dopants and free-radical initiators.

11. An electro-optical display comprising the liquid-crystalline medium according to claim 1 .

12. An electro-optical display having active-matrix addressing, wherein the electro-optical display contains, as dielectric, a liquid-crystalline medium according to claim 1 .

13. The electro-optical display according to claim 12 , wherein the electro-optical display is a VA, PSA, PS-VA, PALC, FFS, PS-FFS, IPS or PS-IPS display.

14. The liquid-crystalline medium according to claim 1 further comprising one or more compounds selected from the compounds of formulae BC, CR, PH-1, PH-2 and BF,

Assignees

• Merck Patent Gmbh

Inventors

• Klasen-Memmer Melanie
• Reuter Marcus
• Fortte Rocco
• Pauluth Detlef
• Bremer Matthias
• Haensel Helmut
• Hirschmann Harald

Classifications

• C09K19/322

  Compounds containing a naphthalene ring or a completely or partially hydrogenated naphthalene ring · CPC title

• C09K19/20

  linked by a chain containing carbon and oxygen atoms as chain links, e.g. esters {or ethers} · CPC title

• C09K2019/122

  Ph-Ph · CPC title

• C09K19/10

  containing at least two benzene rings · CPC title

• C09K2019/3027

  Compounds comprising 1,4-cyclohexylene and 2,3-difluoro-1,4-phenylene · CPC title