Liquid-crystalline medium

• US 8,168,081 B2
• Filed: 07/17/2007
• Issued: 05/01/2012
• Est. Priority Date: 07/19/2006
• Status: Active Grant

• Current Assignee: Merck Patent GmbH (Merck & Co., Inc.)
• Original Assignee: Merck Patent GmbH (Merck & Co., Inc.)
• Inventors: Klasen-Memmer, Melanie, Bernatz, Georg, Saito, Izumi, Bremer, Matthias, Lietzau, Lars, Reiffenrath, Volker
• Primary Examiner(s): Visconti, Geraldina
• Application Number:
  US12/373,398
• Publication Number:
  US 20090309066A1
• Time in Patent Office: 1,750 Days
• Field of Search: 252/299.01, 252/299.1, 252/299.6, 252/299.63, 428/1.1, 430/20, 349/117
• US Class Current: 252/299.6
• CPC Class Codes: C09K 19/12 at least two benzene rings directly linked, e.g. biphenyls
• CPC Class Codes: C09K 19/3098 Unsaturated non-aromatic rings, e.g. cyclohexene rings
• CPC Class Codes: C09K 19/42 Mixtures of liquid crystal compounds covered by two or more of the preceding groups C09K19/06 - C09K19/40
• CPC Class Codes: C09K 19/44 containing compounds with benzene rings directly linked
• CPC Class Codes: C09K 2019/0407 containing a carbocyclic ring, e.g. dicyano-benzene, chlorofluoro-benzene or cyclohexanone
• CPC Class Codes: C09K 2019/0448 the end chain group being a polymerizable end group, e.g. -Sp-P or acrylate
• CPC Class Codes: C09K 2019/3027 Compounds comprising 1,4-cyclohexylene and 2,3-difluoro-1,4-phenylene
• CPC Class Codes: C09K 2323/00 Functional layers of liquid crystal optical display excluding electroactive liquid crystal layer characterised by chemical composition

Abstract

The invention relates to a liquid-crystalline medium based on a mixture of dielectrically negative, polar compounds which comprises at least one compound of the formula I

• • in which the parameters have the meanings indicated in claim 1,
  • to the use thereof in an electro-optical display, particularly in an active-matrix display based on the VA, ECB, PALC, FFS or IPS effect, and to displays of this type.

Claims

1. A liquid-crystalline medium comprising a mixture of dielectrically negative, polar compounds, which comprises

one or more compounds of formula I

2. A medium according to claim 1, comprising

a) a first dielectrically negative, mesogenic component (component A), which consists of one or more dielectrically negative compound(s) of formula I,

and

b) a second dielectrically negative, mesogenic component (component B), which consists of one or more dielectrically negative compound(s) of formula II, wherein at least one of the compounds of formula II is a compound selected from formulae II-3, II-5, II-6 and II-7

3. A medium according to claim 1, comprising one or more compounds of formula I in which at least one of the groups

4. A medium according to claim 1, comprising two, three, four or more compounds of formula I.

5. A medium according to claim 1, wherein the proportion of compounds of formula I in the mixture as a whole is at least 15% by weight.

6. A medium according to claim 1, wherein the proportion of compounds of formulae IA-1 and IB-1 to IB-4 in the mixture as a whole is at least 20% by weight

7. A medium according to claim 1, comprising at least one compound of formula IA-1, IB-1 to IB-3 or IB-9

8. A medium according to claim 1, comprising one or more compounds of formula I in which Z¹¹ to Z¹³ each denote a single bond.

9. A medium according to claim 2, comprising at least one of

(a) 2-80% by weight of one or more compounds of formula I,

(b) 2-80% by weight of one or more compounds of formula II,

(c) 2-80% by weight of one or more compounds of formula III, and

(d) 2-80% by weight of one or more compounds selected from formulae IV and V,

where the total content of all compounds of formulae I, II, III, IV and V in the medium is 100% by weight or less.

10. An electro—

optical display, which contains, as dielectric, a liquid-crystalline medium according to claim 1.

11. A display according to claim 10, which has an active-matrix addressing device.

12. A display according to claim 10, which is based on the VA, ECB, PALC, FFS or IPS effect.

13. A method of generating an electro-optical effect comprising applying a voltage to an electro-optical display according to claim 10.

14. A method according to claim 13, wherein said electro-optical display has an active-matrix addressing device.

15. A medium according to claim 1, wherein

R²¹ denotes alkyl or alkenyl, and

R²² denotes alkyl, alkenyl, alkoxy or alkenyloxy.

16. A medium according to claim 1, which comprises one or more compounds of formula II-5.

17. A medium according to claim 1, which comprises one or more compounds of formula II-7.

18. A medium according to claim 1, which comprises one or more compounds of formula II-5 and one or more compounds of formula II-7.

19. A medium according to claim 2, wherein said medium contains component (C).

20. A medium according to claim 2, wherein said medium contains component (D).

21. A medium according to claim 2, wherein said medium contains component (E).

22. A medium according to claim 1, wherein said medium comprises at least one of a dielectrically negative compound of formula II, which is not a compound of formula II-3, II-5, II-6 or II-7