Liquid-crystal medium

Abstract

A liquid-crystalline medium, in particular based on a mixture of polar compounds, having compounds of formulae Y, CY, PY and/or LY, and compounds of formula S1 and/or S2: ##STR00001##

Claims

1. A liquid crystal (LC) medium comprising one or more compounds selected from the compounds of formulae Y, CY, PY and LY, one or more compounds selected from the compounds of formula S1 and one or more compounds selected from the compounds of formula S2, and wherein the medium has positive dielectric anisotropy: ##STR00580## wherein the individual radicals, independently of each other and on each occurrence identically or differently, have the following meanings: ##STR00581## with at least one ring ##STR00582## being cyclohexenylene, R.sup.1, R.sup.2 are, each independently, alkyl having 1 to 12 C atoms, where, in addition, one or two non-adjacent CH.sub.2 groups may be replaced by O, CHCH, CO, OCO or COO in such a way that O atoms are not linked directly to one another, Z.sup.x, Z.sup.y are, each independently, CH.sub.2CH.sub.2, CHCH, CF.sub.2O, OCF.sub.2, CH.sub.2O, OCH.sub.2, COO, OCO, C.sub.2F.sub.4, CFCF, CHCHCH.sub.2O- or a single bond, L.sup.1-4 are, each independently, F, Cl, OCF.sub.3, CF.sub.3, CH.sub.3, CH.sub.2F, or CHF.sub.2, R.sup.a-d are, each independently, straight chain or branched alkyl with 1 to 10 C atoms, X is H, CH.sub.3, OH or O.sup., A is a straight-chain, branched or cyclic alkylene with 1 to 20 C-atoms which is optionally substituted, a is 1 or 2, b is 0 or 1, f is 1 or 2, n is an integer from 1 to 6.

2. The LC medium according to claim 1, wherein the compounds of formula S1 are selected from the compounds of the following subformulae: ##STR00583## wherein n1 is an integer from 2 to 12 and wherein one or more H-atoms in the radical (CH.sub.2).sub.n1 are optionally replaced by a methyl, ethyl, propyl, butyl, pentyl or hexyl group.

3. The LC medium according to claim 2, wherein the compounds of formula S1 are selected from the compounds of the following subformulae: ##STR00584## ##STR00585##

4. The LC medium according to claim 1, wherein the compounds of formula S2 are selected from the compounds of the following subformulae: ##STR00586##

5. The LC medium according to claim 1, which additionally comprises one or more compounds selected from the compounds of formulae AA and BB: ##STR00587## in which the individual radicals have the following meanings: ##STR00588## are each, independently of one another, and on each occurrence, identically or differently ##STR00589## R.sup.21, R.sup.31, each, independently of one another, denote alkyl, alkoxy, oxaalkyl or alkoxyalkyl having 1 to 9 C atoms or alkenyl or alkenyloxy having 2 to 9 C atoms, all of which are optionally fluorinated, X.sup.0 denotes F, Cl, halogenated alkyl or alkoxy having 1 to 6 C atoms or halogenated alkenyl or alkenyloxy having 2 to 6 C atoms, Z.sup.31 is CH.sub.2CH.sub.2, CF.sub.2CF.sub.2, COO, trans-CHCH-, trans-CFCF-, CH.sub.2O or a single bond, L.sup.21, L.sup.22, L.sup.31, L.sup.32 denote, each independently, H or F, g denotes 0, 1, 2 or 3.

6. The LC medium according to claim 1, which additionally comprises one or more compounds selected from the compounds of formula CC: ##STR00590## in which the individual radicals have the following meanings: ##STR00591## each, independently of one another, and on each occurrence, identically or differently, are ##STR00592## R.sup.41, R.sup.42 each, independently of one another, are alkyl, alkoxy, oxaalkyl or alkoxyalkyl having 1 to 9 C atoms or alkenyl or alkenyloxy having 2 to 9 C atoms, all of which are optionally fluorinated, Z.sup.41, Z.sup.42 each, independently of one another, are CH.sub.2CH.sub.2, COO, trans-CHCH-, trans-CFCF-, CH.sub.2O, CF.sub.2O, CC or a single bond, h 0, 1, 2 or 3.

7. The LC medium according to claim 1, which additionally comprises one or more compounds selected from the compounds of formulae AN and AY: ##STR00593## in which the individual radicals, on each occurrence identically or differently, and each, independently of one another, have the following meaning: ##STR00594## R.sup.A1 is alkenyl having 2 to 9 C atoms or, if at least one of the rings X, Y and Z denotes cyclohexenyl, also one of the meanings of R.sup.A2, R.sup.A2 is alkyl having 1 to 12 C atoms, in which, in addition, one or two non-adjacent CH.sub.2 groups may be replaced by O, CHCH, CO, OCO or COO in such a way that O atoms are not linked directly to one another, Z.sup.x is CH.sub.2CH.sub.2, CHCH, CF.sub.2O, OCF.sub.2, CH.sub.2O, OCH.sub.2, COO, OCO, C.sub.2F.sub.4, CFCF, CHCHCH.sub.2O, or a single bond, L.sup.1,2 are, each independently, H, F, Cl, OCF.sub.3, CF.sub.3, CH.sub.3, CH.sub.2F or CHF.sub.2H, x is 1 or 2, z is 0 or 1.

8. An LC display comprising an LC medium as defined in claim 1.

9. The LC display according to claim 8, which is a VA, PSA, PS-VA, PA-VA, PALC, FFS, PS-FFS, IPS or PS-IPS display.

10. The LC medium according to claim 1, wherein: R.sup.1, R.sup.2 are, each independently, alkyl or alkoxy having 1 to 6 C atoms, Z.sup.x, Z.sup.y are each a single bond, R.sup.a-d are, each independently, straight chain or branched alkyl with 1 to 6 C atoms, and n is the integer 3.

11. The LC medium according to claim 1, wherein R.sup.a-d are each methyl.

Description

EXAMPLE 1

(1) An LC mixture with negative dielectric anisotropy is formulated as follows.

(2) TABLE-US-00009 CC-3-V 29.00% cl.p. 80.1 C..sup. CCY-3-O1 8.00% n 0.1052 CCY-3-O2 6.00% 4.7 CCY-4-O2 2.00% .sub.|| 3.9 CLY-3-O2 8.50% K.sub.3/K.sub.1 1.10 CLY-3-O3 7.50% .sub.1 125 mPa s CPY-2-O2 10.00% CPY-3-O2 7.50% CY-3-O2 6.50% PY-3-O2 10.00% Y-4O-O4 5.00%

(3) To the above mixture are added 200 ppm of stabilizer S1-2a and 400 ppm of stabilizer S2a.

(4) ##STR00578##

EXAMPLE 2

(5) An LC mixture with negative dielectric anisotropy is formulated as follows.

(6) TABLE-US-00010 CC-3-V 23.00% cl.p. 79.6 C. CC-3-V1 5.00% n 0.1156 CCY-3-O1 5.00% 4.7 CCY-3-O2 1.00% .sub.|| 3.9 CCY-4-O2 2.50% K.sub.3/K.sub.1 1.12 CLY-3-O2 8.00% .sub.1 133 mPa s CLY-3-O3 7.00% CPY-2-O2 10.00% CPY-3-O2 11.00% CY-3-O2 11.00% PY-3-O2 16.50%

(7) To the above mixture are added 200 ppm of stabilizer S1-2a and 400 ppm of stabilizer S2a.

EXAMPLE 3

(8) An LC mixture with negative dielectric anisotropy is formulated as follows.

(9) TABLE-US-00011 CC-3-V 22.00% cl.p. 90.6 C. CC-3-V1 5.00% n 0.1063 CCPC-33 3.00% 4.6 CCY-3-O1 6.00% .sub.|| 3.7 CCY-3-O2 9.50% K.sub.3/K.sub.1 1.18 CCY-4-O2 9.00% .sub.1 160 mPa s CPY-2-O2 10.00% CPY-3-O2 10.00% CY-3-O2 10.00% CY-5-O2 6.50% PY-3-O2 9.00%

(10) To the above mixture are added 200 ppm of stabilizer S1-2a and 400 ppm of stabilizer S2a.

EXAMPLE 4

(11) An LC mixture with negative dielectric anisotropy is formulated as follows.

(12) TABLE-US-00012 BCH-32 2.00% cl.p. 80.1 C. CC-3-V 29.00% n 0.1051 CCY-3-O1 7.00% 4.5 CCY-3-O3 6.00% .sub.|| 4.0 CCY-4-O2 8.00% K.sub.3/K.sub.1 1.13 CLY-3-O2 6.00% .sub.1 123 mPa s CPY-2-O2 10.00% CPY-3-O2 11.00% CY-3-O2 7.00% PY-3-O2 9.00% Y-4O-O4 5.00%

(13) To the above mixture are added 150 ppm of stabilizer S1-2a and 400 ppm of stabilizer S2a.

EXAMPLE 5

(14) An LC mixture with negative dielectric anisotropy is formulated as follows.

(15) TABLE-US-00013 CC-3-V 29.50% cl.p. 84.7 C. CC-3-V1 4.00% n 0.0966 CCY-3-O2 7.00% 3.6 CCY-3-O3 5.00% .sub.|| 3.6 CCY-4-O2 6.00% K.sub.3/K.sub.1 1.13 CCY-5-O2 7.00% .sub.1 128 mPa s CPY-3-O2 9.00% CPY-2-O2 8.50% CY-3-O4 10.00% CY-5-O2 10.00% PGIGI-3-F 4.00%

(16) To the above mixture are added 100 ppm of stabilizer S1-2a and 400 ppm of stabilizer S2a.

EXAMPLE 6

(17) An LC mixture with negative dielectric anisotropy is formulated as follows.

(18) TABLE-US-00014 CC-3-V 33.00% cl.p. 80.8 C. CCY-3-O1 6.00% n 0.1066 CCY-3-O2 6.00% 4.0 CCY-4-O2 8.00% .sub.|| 3.7 CCY-5-O2 3.00% K.sub.3/K.sub.1 1.13 CPY-2-O2 9.00% .sub.1 116 mPa s CPY-3-O2 9.00% CY-3-O2 9.00% CY-5-O2 3.00% PY-3-O2 9.00% PYP-2-3 5.00%

(19) To the above mixture are added 150 ppm of stabilizer S1-2a and 400 ppm of stabilizer S2a.

EXAMPLE 7

(20) An LC mixture with negative dielectric anisotropy is formulated as follows.

(21) TABLE-US-00015 BCH-32 6.50% cl.p. 74.9 C. CC-3-V 33.00% n 0.1009 CCY-3-O1 4.00% 3.7 CCY-3-O2 4.50% .sub.|| 3.8 CCY-3-O3 6.00% K.sub.3/K.sub.1 1.11 CCY-4-O2 6.00% .sub.1 10 mPa s CPY-2-O2 9.00% CPY-3-O2 10.00% CY-3-O2 9.00% PY-3-O2 7.00% Y-4O-O4 5.00%

(22) To the above mixture are added 100 ppm of stabilizer S1-2a and 400 ppm of stabilizer S2a.

EXAMPLE 8

(23) An LC mixture with negative dielectric anisotropy is formulated as follows.

(24) TABLE-US-00016 BCH-32 2.00% cl.p. 80.3 C. CC-3-V 29.00% n 0.1042 CCY-3-O1 7.00% 4.3 CCY-3-O3 7.00% .sub.|| 4.0 CCY-4-O2 8.00% K.sub.3/K.sub.1 1.11 CLY-3-O2 6.00% .sub.1 118 mPa s CPY-2-O2 9.00% CPY-3-O2 11.00% CY-3-O2 7.00% PY-3-O2 9.00% Y-4O-O4 5.00%

(25) To the above mixture are added 100 ppm of stabilizer S1-2a and 400 ppm of stabilizer S2a.

EXAMPLE 9

(26) An LC mixture with negative dielectric anisotropy is formulated as follows.

(27) TABLE-US-00017 CC-3-V 32.00% cl.p. 85.3 C. CCY-3-O1 6.50% n 0.1112 CCY-3-O2 6.00% 4.0 CCY-4-O2 6.00% .sub.|| 3.8 CLY-3-O3 13.00% K.sub.3/K.sub.1 1.07 CPY-2-O2 9.00% .sub.1 128 mPa s CPY-3-O2 7.50% PP-1-2V1 2.50% PY-1-O4 9.00% PY-3-O2 8.50%

(28) To the above mixture are added 200 ppm of stabilizer S1-2a and 400 ppm of stabilizer S2a.

EXAMPLE 10

(29) An LC mixture with positive dielectric anisotropy is formulated as follows.

(30) TABLE-US-00018 APUQU-2-F 4.00% cl.p. 85.0 C. CC-3-V 39.00% n 0.1011 CC-3-V1 5.50% 5.9 CCP-30CF3 6.00% .sub.|| 9.3 CCP-V-1 14.00% K.sub.3/K.sub.1 1.12 CPGU-3-OT 3.00% .sub.1 66 mPa s PGP-2-2V 4.50% DPGU-4-F 3.00% PPGU-3-F 1.00% PUQU-3-F 14.00% CCY-3-O2 6.00%

(31) To the above mixture are added 100 ppm of stabilizer S1-2a and 300 ppm of stabilizer S2a.

EXAMPLE 11

(32) An LC mixture with positive dielectric anisotropy is formulated as follows.

(33) TABLE-US-00019 APUQU-2-F 5.50% cl.p. 80.3 C. CC-3-V 38.50% n 0.1124 CCP-V-1 12.50% 10.1 CCP-V2-1 4.50% .sub.|| 14.4 CDUQU-3-F 2.50% K.sub.3/K.sub.1 1.13 DGUQU-4-F 5.50% .sub.1 77 mPa s DPGU-4-F 4.50% PGP-2-2V 6.00% PGUQU-3-F 7.00% PGUQU-4-F 6.50% PPGU-3-F 1.00% Y-4O-O4 6.00%

(34) To the above mixture are added 150 ppm of stabilizer S1-2a and 300 ppm of stabilizer S2a.

EXAMPLE 12

(35) An LC mixture with positive dielectric anisotropy is formulated as follows.

(36) TABLE-US-00020 APUQU-2-F 5.50% cl.p. 80.3 C. CC-3-V 38.50% n 0.1124 CCP-V-1 12.50% 10.1 CCP-V2-1 4.50% .sub.|| 14.4 CDUQU-3-F 2.50% K.sub.3/K.sub.1 1.13 DGUQU-4-F 5.50% .sub.1 77 mPa s DPGU-4-F 4.50% PGP-2-2V 6.00% PGUQU-3-F 7.00% PGUQU-4-F 6.50% PPGU-3-F 1.00% Y-4O-O4 6.00%

(37) To the above mixture are added 100 ppm of stabilizer S1-1a and 400 ppm of stabilizer S2a.

(38) ##STR00579##

EXAMPLE 13

(39) An LC mixture with positive dielectric anisotropy is formulated as follows.

(40) TABLE-US-00021 BCH-3F.F.F 10.00% cl.p. 85.4 C. CC-3-V 23.50% n 0.1071 CC-3-V1 7.00% 6.8 CCGU-3-F 5.00% .sub.|| 10.3 CCP-30CF3 9.00% K.sub.3/K.sub.1 1.10 CCP-3-F.F.F 8.00% .sub.1 83 mPa s CCP-V-1 11.00% CCP-V2-1 3.00% DPGU-4-F 3.00% PGP-2-2V 3.00% PPGU-3-F 1.00% PUQU-3-F 10.50% PY-3-O2 6.00%

(41) To the above mixture are added 100 ppm of stabilizer S1-2a and 400 ppm of stabilizer S2a.

EXAMPLE 14

(42) An LC mixture with positive dielectric anisotropy is formulated as follows.

(43) TABLE-US-00022 BCH-3F.F.F 7.00% cl.p. 100.0 C. CBC-33 3.00% n 0.1009 CC-3-V 25.00% 4.5 CCGU-3-F 6.00% .sub.|| 8.3 CCP-3-1 4.50% K.sub.3/K.sub.1 1.17 CCP-30CF3 8.00% .sub.1 125 mPa s CCP-V-1 13.50% CCP-V2-1 6.00% CCQU-3-F 8.00% CPGP-5-2 3.00% DPGU-4-F 2.50% PPGU-3-F 1.00% PUQU-3-F 4.50% Y-4O-O4 8.00%

(44) To the above mixture are added 100 ppm of stabilizer S1-2a and 400 ppm of stabilizer S2a.

EXAMPLE 15

(45) An LC mixture with positive dielectric anisotropy is formulated as follows.

(46) TABLE-US-00023 APUQU-2-F 3.00% cl.p. 80.7 C. CC-3-V 37.50% n 0.1103 CCP-3-1 3.00% 9.5 CCP-30CF3 3.00% CCP-V-1 15.00% CDUQU-3-F 5.50% CPGU-3-OT 1.50% DPGU-4-F 5.00% PGU-2-F 6.00% PGU-3-F 6.00% PGUQU-3-F 5.00% PGUQU-4-F 5.00% PPGU-3-F 0.50% Y-4O-O4 4.00%

(47) To the above mixture are added 100 ppm of stabilizer S1-1a and 400 ppm of stabilizer S2a.

USE EXAMPLES

(48) The LC medium M10 formulated as in Example 10 is filled into VHR test cells as described above.

(49) The test cells are subjected to thermal stress (100 C.). The VHR is measured as described above after various time intervals.

(50) For comparison purpose the measurement is repeated with reference LC medium MC, which is formulated as in Example 10 except that it only contains stabilizer S1-2a but does not contain stabilizer S2a.

(51) The VHR values are shown in Table 1 below.

(52) TABLE-US-00024 TABLE 1 Heat load MC M10 time/h VHR/% 0 95.1 96.5 24 90.4 93.3 48 89.2 92.6 120 86.4 91.7

(53) It can be seen that LC medium M10, which contains both stabilizers S1-2a and S2a, shows significantly lower decrease of the VHR after long heat exposure compared to LC medium MC, which only contains stabilizer S1-2a but does not contain stabilizer S2a.

(54) Without further elaboration, it is believed that one skilled in the art can, using the preceding description, utilize the present invention to its fullest extent. The preceding preferred specific embodiments are, therefore, to be construed as merely illustrative, and not limitative of the remainder of the disclosure in any way whatsoever.

(55) In the foregoing and in the examples, all temperatures are set forth uncorrected in degrees Celsius and, all parts and percentages are by weight, unless otherwise indicated.

(56) The entire disclosure[s] of all applications, patents and publications, cited herein and of corresponding EP Application No. 16170390.5, filed May 19, 2016 is [are] incorporated by reference herein.

(57) The preceding examples can be repeated with similar success by substituting the generically or specifically described reactants and/or operating conditions of this invention for those used in the preceding examples.

(58) From the foregoing description, one skilled in the art can easily ascertain the essential characteristics of this invention and, without departing from the spirit and scope thereof, can make various changes and modifications of the invention to adapt it to various usages and conditions.