LIQUID-CRYSTALLINE MEDIUM

Abstract

The present invention relates to a liquid-crystal medium which comprises one or more compounds each of formulae I and II

##STR00001##

in which the occurring groups and parameters have the meanings given in claim 1.

Claims

1. Liquid-crystal medium, characterised in that it comprises a) one or more compounds of formula I ##STR00128## in which R.sup.1 denotes H, alkyl or alkoxy having 1 to 12 C atoms, or alkenyl, alkenyloxy or alkoxyalkyl having 2 to 12 C atoms, in which one or more CH.sub.2-groups may be replaced by ##STR00129## and in all of which one or more H atoms may be replaced by fluorine, ##STR00130## on each occurrence, independently of one another, denotes ##STR00131## has one of the meanings given for ##STR00132## and alternatively denotes ##STR00133## L.sup.11 and L.sup.12, independently of one another, denote H or F, L.sup.13 denotes H or methyl, X.sup.11 denotes halogen, halogenated alkyl or alkoxy having 1 to 3 C atoms or halogenated alkenyl or alkenyloxy having 2 or 3 C atoms, m is 0, 1, or 2; and b) one or more compounds of formula II ##STR00134## in which R.sup.21 and R.sup.22 denotes H, alkyl or alkoxy having 1 to 12 C atoms, or alkenyl, alkenyloxy or alkoxyalkyl having 2 to 12 C atoms in which one or more CH.sub.2-groups may be replaced by ##STR00135## and in which one or more H atoms may be replaced by fluorine, n is 0 or 1, ##STR00136## is ##STR00137## L.sup.21 to L.sup.23 independently of one another denote H or F.

2. Liquid-crystal medium according to claim 1, wherein the one or more compounds of formula I are selected from the group of compounds of the formulae I-1 and I-2 ##STR00138## in which L.sup.14 and L.sup.15 independently of one another, denote H or F, and the remaining groups have the meanings given in claim 1 for formula I.

3. Liquid-crystal medium according to claim 1, wherein the medium comprises one or more compounds of formula D ##STR00139## in which one of ##STR00140## denotes ##STR00141## and the other of ##STR00142## denotes ##STR00143## R.sup.D denotes H, alkyl or alkoxy having 1 to 12 C atoms, or alkenyl, alkenyloxy or alkoxyalkyl having 2 to 12 C atoms, in which one or more CH.sub.2-groups may be replaced by ##STR00144## and in which one or more H atoms may be replaced by fluorine, X.sup.D denotes F, CF.sub.3 or OCF.sub.3, and Y.sup.D denotes H or F.

4. Liquid-crystal medium according to claim 1, wherein the medium comprises one or more compounds of formula V ##STR00145## in which ##STR00146## denotes ##STR00147## R.sup.5 is alkyl having 1 to 20 C atoms, which is straight chain or branched, is non-substituted, mono- or poly-substituted by F, Cl or CN, and in which one or more CH.sub.2 groups are optionally replaced, in each case independently from one another, by —O—, —S—, —CO—, —COO—, —OCO—, —OCO—O—, —S—CO—, —CO—S—, —CH═CH— or —C≡C— in such a manner that O and/or S atoms are not linked directly to one another, X.sup.5 is halogen, CF.sub.3 or OCF.sub.3, and i is 0 or 1.

5. Liquid-crystal medium according to claim 1, wherein the medium comprises one or more compounds selected from the group of compounds of formulae II-1, II-2 and II-3 ##STR00148## in which the occurring groups have the meanings given in claim 1.

6. Liquid-crystal medium according to claim 1, wherein the medium comprises one or more compounds of formula III ##STR00149## in which R.sup.31, R.sup.32 is alkyl having 1 to 20 C atoms, which is straight chain or branched, is non-substituted, mono- or poly-substituted by F, Cl or CN, and in which one or more CH.sub.2 groups are optionally replaced, in each case independently from one another, by —O—, —S—, —CO—, —COO—, —OCO—, —OCO—O—, —S—CO—, —CO—S—, —CH═CH— or —C≡C— in such a manner that O and/or S atoms are not linked directly to one another, ##STR00150## to ##STR00151## are independently of each other ##STR00152## Z.sup.31 and Z.sup.32 on each occurrence, identically or differently, denote —CH.sub.2CH.sub.2—, —CF.sub.2CF.sub.2—, —CF.sub.2CH.sub.2—, —COO—, trans- —CH═CH—, trans- —CF═CF—, —CH.sub.2O—, —CF.sub.2O—, —C≡C— or a single bond p is 0, 1 or 2.

7. Liquid-crystal medium according to claim 6, wherein the medium comprises a compound of formula III-3 ##STR00153## in which the occurring groups have the meanings given for formula III in claim 6.

8. Liquid-crystal medium according to claim 1, wherein the medium has a clearing temperature of 90° C. or more.

9. Liquid-crystal medium according to claim 1, wherein the medium has a dielectric anisotropy in the range of from 2 to 20, measured at 1 kHz and 20° C.

10. Process for the preparation of a liquid-crystal medium according claim 1, characterised in that one or more compounds of formula I, and one or more compounds of formula II, are mixed with one or more further compounds and/or with one or more additives.

11. (canceled)

12. 3D lens, characterised in that it contains a liquid-crystal medium according to claim 1.

13. Liquid crystal display comprising one or more 3D lenses according to claim 12.

14. Process for operating a 3D liquid crystal display by addressing one or more 3D lenses according to claim 12.

15. A process for the preparation of a liquid-crystal medium according to claim 3, characterised in that one or more compounds of formula I, and one or more compounds of formula II and one or more compounds of formula D, are mixed with one or more further compounds and/or with one or more additives.

Description

EXAMPLES

[0210] The following examples illustrate the present invention without limiting it in any way. However, it becomes clear to the person skilled in the art from the physical properties what properties can be achieved and in what ranges they can be modified. In particular, the combination of the various properties which can preferably be achieved is thus well defined for the person skilled in the art.

EXAMPLES

[0211] The nematic liquid-crystal mixtures C1, N1, N2 and N3 are prepared as follows:

Comparative Example C1

[0212]

TABLE-US-00006 CC-3-V1 8.0% T.sub.(N, I). [° C.]: 101 CCP-3-OT 7.0% Δn (589.3 nm, 20° C.) 0.1364 CCP-4-OT 5.0% n.sub.e (589.3 nm, 20° C.) 1.6111 CCQU-2-F 9.0% n.sub.o (589.3 nm, 20° C.) 1.4747 CCQU-3-F 10.0% Δε (1 kHz, 20° C.): 35.0 CDUQU-3-F 10.0% ε.sub.∥ (1 kHz, 20° C.): 40.4 CPGU-3-OT 8.0% ε.sub.⊥ (1 kHz, 20° C.): 5.4 DGUQU-4-F 8.0% γ.sub.1 [mPa .Math. s], (20° C.): 258 PGUQU-3-F 8.0% K.sub.1 [pN], (20° C.): 12.7 PGUQU-4-F 7.0% K.sub.3 [pN], (20° C.): 12.1 PGUQU-5-F 6.0% V.sub.0 [V], (20° C.): 0.63 PUQU-3-F 14.0% Σ 100.0%

Mixture Example N1

[0213]

TABLE-US-00007 CC-3-V1 13.0% T.sub.(N, I). [° C.]: 95 CCQU-2-F 7.0% Δn (589.3 nm, 20° C.) 0.1336 CCQU-3-F 9.0% n.sub.e (589.3 nm, 20° C.) 1.6130 CCQU-5-F 8.0% n.sub.o (589.3 nm, 20° C.) 1.4794 CDU-2-F 7.0% Δε (1 kHz, 20° C.): 11.9 CDU-3-F 8.0% ε.sub.∥ (1 kHz, 20° C.): 15.8 CDUQU-3-F 8.0% ε.sub.⊥ (1 kHz, 20° C.): 3.9 CPGU-3-OT 8.0% γ.sub.1 [mPa .Math. s], (20° C.): 144 CP-3-O1 13.0% K.sub.1 [pN], (20° C.): 15.1 PPTUI-3-4 15.0% K.sub.3 [pN], (20° C.): 13.4 PUQU-3-F 4.0% V.sub.0 [V], (20° C.): 1.17 Σ 100.0%

Mixture Example N2

[0214]

TABLE-US-00008 CC-3-V1 6.0% T.sub.(N, I). [° C.]: 100 CC-3-O1 10.0% Δn (589.3 nm, 20° C.) 0.1310 CCPC-33 3.0% n.sub.e (589.3 nm, 20° C.) 1.6113 CCQU-2-F 8.0% n.sub.o (589.3 nm, 20° C.) 1.4803 CCQU-3-F 8.0% Δε (1 kHz, 20° C.): 9.1 CCQU-5-F 8.0% ε.sub.∥ (1 kHz, 20° C.): 12.7 CDU-3-F 3.0% ε.sub.⊥ (1 kHz, 20° C.): 3.7 CDUQU-3-F 12.0% γ.sub.1 [mPa .Math. s], (20° C.): 155 CPGU-3-OT 8.0% K.sub.1 [pN], (20° C.): 15.4 CP-3-O1 9.0% K.sub.3 [pN], (20° C.): 14.4 CP-3-O2 10.0% V.sub.0 [V], (20° C.): 1.37 PPTUI-3-4 15.0% Σ 100.0%

Mixture Example N3

[0215]

TABLE-US-00009 CC-3-V1 6.0% T.sub.(N, I). [° C.]: 102.5 CCH-3-O1 10.0% Δn (589.3 nm, 20° C.) 0.1445 CCZPC-3-3 3.0% n.sub.e (589.3 nm, 20° C.) 1.6280 CCQU-2-F 6.0% n.sub.o (589.3 nm, 20° C.) 1.4835 CCQU-3-F 7.0% Δε (1 kHz, 20° C.): 8.1 CCQU-5-F 8.0% ε.sub.∥ (1 kHz, 20° C.): 11.7 CDU-3-F 3.0% ε.sub.⊥ (1 kHz, 20° C.): 3.6 CDUQU-3-F 10.0% γ.sub.1 [mPa .Math. s], (20° C.): 160.0 CPGU-3-OT 8.0% K.sub.1 [pN], (20° C.): 16.1 CP-3-O1 9.0% K.sub.3 [pN], (20° C.): 15.3 CP-3-O2 10.0% V.sub.0 [V], (20° C.): 1.48 PPTUI-3-4 20.0% Σ 100.0%

[0216] The mixtures N1 to N3 are highly suitable for application in 3D lenses, especially of the plastic mould type.

[0217] Table 1 shows the variation of the thickness of an LC lens with the applied voltage, fabricated with liquid-crystal mixture N-1 in comparison with a lens fabricated with the medium C-1. The lenses are flattened upon application of an electric field.

[0218] Without wishing to be bound by theory, it is assumed that the higher voltage necessary to achieve a given thickness with the medium N1 according to the invention is due to the lower value of ell. Surprisingly, despite the higher switching voltage less cross-talk is observed in a device.

TABLE-US-00010 TABLE 1 Lens Thickness Voltage [V] [μm] C-1 N-1 33 0 0 25 1 2.5 20 2 4.5 15 4 8 10 6 12.5 5 12 19 1 33 33