LC medium

Abstract

LC media and LC displays containing an LC medium with positive dielectric anisotropy, which contains one or more compounds of formula I in a concentration of >0 and ≤10% ##STR00001##
and displays addressed by an active matrix and in particular displays of the IPS, PS-IPS, FFS, PS-FFS, HB-FFS, U-IPS, TN, PS-TN, STN or TN-TFT mode.

Claims

1. An LC medium with positive dielectric anisotropy, wherein said LC medium has a clearing point ≥105° C. and a birefringence from 0.10 to 0.13, and comprises at least one compound of formula I in a total concentration of said at least one compound of formula I of >0 and ≤10% ##STR00422## in which R.sup.1 and R.sup.2 independently of each other denote alkyl having 1 to 6 C atoms, and at least one compound of formula XII ##STR00423## in which X.sup.0 is F, Cl, CN, SF.sub.5, SCN, NCS, a halogenated alkyl radical, a halogenated alkenyl radical, a halogenated alkoxy radical or a halogenated alkenyloxy radical having up to 6 C atoms, “alkenyl” denote C.sub.2-6-alkenyl, and L denotes H or F.

2. An LC medium with positive dielectric anisotropy, comprising at least one compound of formula I in a total concentration of said at least one compound of formula I of >0 and ≤10% ##STR00424## in which R.sup.1 and R.sup.2 independently of each other denote alkyl having 1 to 6 C atoms, and at least one compound of formula XII ##STR00425## in which X.sup.0 is F, Cl, CN, SF.sub.5, SCN, NCS, a halogenated alkyl radical, a halogenated alkenyl radical, a halogenated alkoxy radical or a halogenated alkenyloxy radical having up to 6 C atoms, “alkenyl” denote C.sub.2-6-alkenyl, and L denotes H or F and at least one compound of the following formulae III6, III9, III20 and/or III21 ##STR00426## in which R.sup.0 is an unsubstituted or halogenated alkyl or alkoxy radical having 1 to 15 C atoms, in which one or more CH.sub.2 groups are each optionally replaced, independently of one another, by —C≡C—, —CF.sub.2O—, —CH═CH—, ##STR00427## —O—, —CO—O— or —O—CO— in such a way that O atoms are not linked directly to one another, or denotes ##STR00428## X.sup.0 is F, Cl, CN, SF.sub.5, SCN, NCS, a halogenated alkyl radical, a halogenated alkenyl radical, a halogenated alkoxy radical or a halogenated alkenyloxy radical having up to 6 C atoms, and Y.sup.2 is H or F.

3. The LC medium according to claim 2, wherein the at least one compound of formula I are one or more of the following formulae ##STR00429##

4. The LC medium according to claim 2, wherein the total concentration of the at least one compound of formula I is 1 0.0 to 10%.

5. The LC medium according to claim 2, additionally comprising at least one compound of the following formulae ##STR00430## wherein the individual radicals, independently of each other and on each occurrence identically or differently, have the following meanings ##STR00431## R.sup.0 is an unsubstituted or halogenated alkyl or alkoxy radical having 1 to 15 C atoms, in which one or more CH.sub.2 groups are each optionally replaced, independently of one another, by —C≡C—, —CF.sub.2O—, —CH═CH—, ##STR00432## —O—, —CO—O— or —O—CO— in such a way that O atoms are not linked directly to one another, or denotes ##STR00433## X.sup.0 is F, Cl, CN, SF.sub.5, SCN, NCS, a halogenated alkyl radical, a halogenated alkenyl radical, a halogenated alkoxy radical or a halogenated alkenyloxy radical having up to 6 C atoms, Y.sup.0 is H or CH.sub.3, and Y.sup.1-6 is H or F.

6. The LC medium according to claim 2, further comprising at least one compound of the following formulae ##STR00434## in which R.sup.0 is an unsubstituted or halogenated alkyl or alkoxy radical having 1 to 15 C atoms, in which one or more CH.sub.2 groups are each optionally replaced, independently of one another, by —C≡C—, —CF.sub.2O—, —CH═CH—, ##STR00435## —O—, —CO—O— or —O—CO— in such a way that O atoms are not linked directly to one another, or denotes ##STR00436## and X.sup.0 is F, Cl, CN, SF.sub.5, SCN, NCS, a halogenated alkyl radical, a halogenated alkenyl radical, a halogenated alkoxy radical or a halogenated alkenyloxy radical having up to 6 C atoms.

7. The LC medium according to claim 2, further comprising at least one compound of the following formulae ##STR00437## in which R.sup.0 is an unsubstituted or halogenated alkyl or alkoxy radical having 1 to 15 C atoms, in which one or more CH.sub.2 groups are each optionally replaced, independently of one another, by —C≡C—, —CF.sub.2O—, —CH═CH—, ##STR00438## —O—, —CO—O— or —O—CO— in such a way that O atoms are not linked directly to one another, or denotes ##STR00439## X.sup.0 is F, Cl, CN, SF.sub.5, SCN, NCS, a halogenated alkyl radical, a halogenated alkenyl radical, a halogenated alkoxy radical or a halogenated alkenyloxy radical having up to 6 C atoms, Y.sup.1-4 is H or F, Z.sup.0 denotes —C.sub.2H.sub.4—, —(CH.sub.2).sub.4—, —CH═CH—, —CF═CF—, —C.sub.2F.sub.4—, —CH.sub.2CF.sub.2—, —CF.sub.2CH.sub.2—, —CH.sub.2O—, —OCH.sub.2—, —COO— or —OCF.sub.2—, and in formulae V and VI also a single bond, and in formulae V and VIII also —CF.sub.2O—, r denotes 0 or 1, and s denotes 0 or 1.

8. The LC medium according to claim 2, further comprising at least one compound of the following formulae ##STR00440## in which R.sup.0 is an unsubstituted or halogenated alkyl or alkoxy radical having 1 to 15 C atoms, in which one or more CH.sub.2 groups are each optionally replaced, independently of one another, by —C≡C—, —CF.sub.2O—, —CH═CH—, ##STR00441## —O—, —CO—O— or —O—CO— in such a way that 0 atoms are not linked directly to one another, or denotes ##STR00442##

9. The LC medium according to claim 2, additionally comprising at least one compound of the following formulae: ##STR00443## in which “alkyl” denotes C.sub.1-6-alkyl, “alkenyl” denote C.sub.2-6-alkenyl, R″ denotes C.sub.1-6-alkyl, C.sub.1-6-alkoxy or C.sub.2-6-alkenyl, R.sup.a1, R.sup.b1 denote independently of each other CH.sub.3 or C.sub.2H.sub.5, and i, k are independently of each other 0, 1, 2 or 3.

10. The LC medium according to claim 2, further comprising at least one compound of the following formulae ##STR00444## wherein “alkyl” denotes C.sub.1-6-alkyl.

11. The LC medium according to claim 2, wherein the LC medium does not contain a compound selected from the group consisting of compounds of formulae XXIIIa, XXIIIb and XIV ##STR00445## in which L.sup.1 and L.sup.2 denote independently of one another H or F, R′ denotes on each occurrence identically or differently alkyl or alkoxy with 1 to 12 C atoms, R″ denotes on each occurrence identically or differently alkenyl with 2 to 7 C atoms which contains a terminal vinyl group, and R′″ denotes R′ or R″.

12. The LC medium according to claim 2, further comprising at least one compound of the following formula ##STR00446## in which R.sup.3 and R.sup.4 each, independently of one another, denote n-alkyl, alkoxy, oxaalkyl, fluoroalkyl or alkenyl, each having up to 6 C atoms.

13. The LC medium according to claim 2, further comprising at least one compound of the following formulae ##STR00447## in which “alkyl” denotes C.sub.1-6-alkyl.

14. The LC medium according to claim 2, further comprising at least one compound of formula XVI ##STR00448## in which R.sup.3 and R.sup.4 each, independently of one another, denote n-alkyl, alkoxy, oxaalkyl, fluoroalkyl or alkenyl, each having up to 6 C atoms, and L denotes H or F.

15. The LC medium according to claim 2, further comprising a compound of formula XVIc2 ##STR00449##

16. The LC medium according to claim 2, comprising at least one compound of formula IA1 ##STR00450## in which R.sup.0 is ethyl or propyl and X.sup.0 is F.

17. The LC medium according to claim 2, further comprising at least one compound of the following formulae ##STR00451## in which R.sup.0 is an unsubstituted or halogenated alkyl or alkoxy radical having 1 to 15 C atoms, in which one or more CH.sub.2 groups are each optionally replaced, independently of one another, by —C≡C—, —CF.sub.2O—, —CH═CH—, ##STR00452## —O—, —CO—O— or —O—CO— in such a way that O atoms are not linked directly to one another, or denotes ##STR00453## X.sup.0 is F, Cl, CN, SF.sub.5, SCN, NCS, a halogenated alkyl radical, a halogenated alkenyl radical, a halogenated alkoxy radical or a halogenated alkenyloxy radical having up to 6 C atoms, and Y.sup.1-4 is H or F.

18. The LC medium according to claim 2, further comprising at least one compound of formula XXIa ##STR00454## in which R.sup.0 denotes ethyl, n-propyl, n-butyl or n-pentyl.

19. The LC medium according to claim 2, further comprising at least one compound of the following formulae ##STR00455## in which R.sub.3 denotes n-alkyl, alkoxy, oxaalkyl, fluoroalkyl or alkenyl, each having up to 6 C atoms, and X.sup.0 is F, Cl, CN, SF.sub.5, SCN, NCS, a halogenated alkyl radical, a halogenated alkenyl radical, a halogenated alkoxy radical or a halogenated alkenyloxy radical having up to 6 C atoms.

20. The LC medium according to claim 2, further comprising at least one compound of formula XXIXa ##STR00456## in which R.sup.3 denotes ethyl, n-propyl, n-butyl or n-pentyl.

21. A process for preparing an LC medium according claim 2, comprising mixing at least one compound of formula I with at least one compound of formula XII and at least one of the compounds of formulae III6, III19, III20, and/or III21.

22. An electro-optical application, shutter glasses, a 3D application, or an LC display or an IPS, PS-IPS, FFS, PS—FFS, HB-FFS, U-IPS, TN, PS-TN, STN or TN-TFT display, comprising the LC medium according to claim 7.

23. The LC medium according to claim 2, wherein the total concentration of the at least one compound of formula I is more than 0.2% and less than 8%.

24. The LC medium according to claim 2, which has a clearing point ≥105° C.

25. A public information display or automotive display comprising the LC medium according to claim 2.

26. A public information display comprising the LC medium according to claim 1.

Description

EXAMPLE 1

(1) The LC mixture N1 is formulated as follows:

(2) TABLE-US-00009 CPGP-5-2 1.0% cl.p. 110.5° C. CPGU-3-OT 1.5% Δn 0.1105 CCG-V-F 8.5% Δε +5.8 CCP-3-1 5.0% ε.sub.∥ 8.9 CCP-3F•F•F 10.0%  K.sub.1 17.2 CCP-V-1 16.0%  K.sub.3 19.7 CCP-V2-1 9.0% K.sub.3/K.sub.1 1.14 CCQU-2-F 5.0% V.sub.0 1.82 V CCQU-3-F 10.0%  LTS −20° C. 1000 h CDU-2-F 10.0%  PGP-2-2V 5.5% CC-3-V1 10.0%  PP-1-2V1 7.0% PP-1-3 1.5%

(3) The mixture contains 1.0% of the compound CPGP-5-2 of formula I.

(4) To 99.9% of the mixture N1 are added 0.1% of the stabiliser S3-1 to give the mixture N11.

EXAMPLE 2

(5) The LC mixture N2 is formulated as follows:

(6) TABLE-US-00010 CPGP-5-2 1.0% cl.p. 109.7° C. CPGU-3-OT 2.5% Δn 0.1115 DGUQU-4-F 3.0% Δε +5.8 CCG-V-F 9.0% ε.sub.∥ 8.8 CCP-3-1 6.0% K.sub.1 17.2 CCP-2F•F•F 5.0% K.sub.3 19.4 CCP-3F•F•F 10.0%  K.sub.3/K.sub.1 1.13 CCP-5F•F•F 8.0% V.sub.0 1.81 V CCP-V-1 16.0%  LTS −20° C. 1000 h CCP-V2-1 4.5% CCQU-3-F 10.0%  PGP-2-2V 4.5% CC-3-V1 11.0%  PP-1-2V1 4.5% PP-1-3 5.0%

(7) The mixture contains 1.0% of the compound CPGP-5-2 of formula I.

(8) To 99.9% of the mixture N2 are added 0.1% of the stabiliser S3-1 to give the mixture N22.

(9) VHR Values

(10) The VHR values of mixtures C11, N11 and N22 are measured at 100C, 3 Hz and 1V in VHR test cell before and after light exposure using a LED lamp.

(11) The results are shown in Table 1.

(12) TABLE-US-00011 TABLE 1 VHR values before and after BL load, 3 Hz/100° C. C11 N11 N22 VHR/% Initial 61.5 74.9 79.6 After BL 144 h 75.4 78.9 82.7

(13) From Table 1 it can be seen that the mixtures N11 and N22 according to the present invention, which contain a compound of formula I, show significantly higher VHR values that mixture C11, both before and after backlight stress.

COMPARISON EXAMPLE 2

(14) The LC mixture C2 is formulated as follows:

(15) TABLE-US-00012 CPGU-3-OT 2.0% cl.p. 109.9° C. DGUQU-4-F 2.5% Δn 0.1116 CCG-V-F 11.0%  Δε +5.6 CCP-3-1 5.0% ε.sub.∥ 8.6 CCP-3F•F•F 10.0%  K.sub.1 17.5 CCP-5F•F•F 8.0% K.sub.3 19.2 CCP-V-1 12.0%  K.sub.3/K.sub.1 1.10 CCP-V2-1 6.0% V.sub.0 1.85 V CCQU-2-F 5.0% CCQU-3-F 10.0%  PGP-2-2V 8.0% CC-3-2V1 2.5% CC-3-V1 11.0%  PP-1-2V1 2.5% PP-1-3 4.5%

(16) The mixture does not show satisfying LTS.

EXAMPLE 3

(17) The LC mixture N3 is formulated as follows:

(18) TABLE-US-00013 CPGP-5-2 0.5% cl.p. 110.0° C. CPGU-3-OT 2.0% Δn 0.1107 DGUQU-4-F 3.0% Δε +5.7 CCG-V-F 9.5% ε.sub.∥ 8.7 CCP-3-1 5.0% K.sub.1 17.6 CCP-3F•F•F 10.0%  K.sub.3 19.2 CCP-5F•F•F 6.5% K.sub.3/K.sub.1 1.09 CCP-V-1 14.0%  V.sub.0 CCP-V2-1 5.5% CCQU-2-F 6.0% CCQU-3-F 10.0%  PGP-2-2V 6.5% CC-3-2V1 3.0% CC-3-V1 11.0%  PP-1-2V1 2.5% PP-1-3 5.0%

(19) The mixture contains 0.5% of the compound CPGP-5-2 of formula I.

EXAMPLE 4

(20) The LC mixture N4 is formulated as follows:

(21) TABLE-US-00014 CPGP-5-2 1.0% cl.p. 109.4° C. CPGU-3-OT 2.0% Δn 0.1109 DGUQU-4-F 3.0% Δε +5.8 CCG-V-F 10.0%  ε.sub.∥ 8.7 CCP-3-1 5.0% K.sub.1 17.5 CCP-3F•F•F 10.0%  K.sub.3 19.4 CCP-5F•F•F 8.0% K.sub.3/K.sub.1 1.11 CCP-V-1 12.5%  V.sub.0 1.83 V CCP-V2-1 5.5% LTS −20° C. 1000 h CCQU-2-F 5.0% CCQU-3-F 10.0%  PGP-2-2V 6.0% CC-3-2V1 3.0% CC-3-V1 11.0%  PP-1-2V1 3.0% PP-1-3 5.0%

(22) The mixture contains 1.0% of the compound CPGP-5-2 of formula I, and shows good LTS at −20° C.

EXAMPLE 5

(23) The LC mixture N5 is formulated as follows:

(24) TABLE-US-00015 CPGP-5-2 2.0% cl.p. 109.3° C. CPGU-3-OT 1.5% Δn 0.1104 DGUQU-4-F 3.0% Δε +5.7 CCG-V-F 9.5% ε.sub.∥ 8.7 CCP-3-1 5.0% K.sub.1 17.5 CCP-3F•F•F 10.0%  K.sub.3 19.3 CCP-5F•F•F 7.5% K.sub.3/K.sub.1 1.10 CCP-V-1 14.0%  V.sub.0 1.84 V CCP-V2-1 4.0% LTS −20° C. 1000 h CCQU-2-F 6.0% CCQU-3-F 10.0%  PGP-2-2V 5.0% CC-3-2V1 3.0% CC-3-V1 11.0%  PP-1-2V1 3.5% PP-1-3 5.0%

(25) The mixture contains 2.0% of the compound CPGP-5-2 of formula I, and shows good LTS at −20° C.

EXAMPLE 6

(26) The LC mixture N6 is formulated as follows:

(27) TABLE-US-00016 CPGP-5-2 4.0% cl.p. 109.3° C. CPGU-3-OT 1.5% Δn 0.1100 DGUQU-4-F 3.0% Δε +5.7 CCG-V-F 9.5% ε.sub.∥ 8.7 CCP-3-1 5.0% K.sub.1 17.5 CCP-3F•F•F 10.0%  K.sub.3 19.6 CCP-5F•F•F 8.0% K.sub.3/K.sub.1 1.12 CCP-V-1 14.0%  V.sub.0 1.83 V CCP-V2-1 2.5% LTS −20° C. 1000 h CCQU-2-F 6.0% LTS −30° C. 1000 h CCQU-3-F 10.0%  PGP-2-2V 2.5% CC-3-2V1 3.0% CC-3-V1 11.0%  PP-1-2V1 5.0% PP-1-3 5.0%

(28) The mixture contains 4.0% of the compound CPGP-5-2 of formula I, and shows good LTS at −20° C. and −30° C.

EXAMPLE 7

(29) The LC mixture N7 is formulated as follows:

(30) TABLE-US-00017 CPGP-5-2 6.0% cl.p. 110.0° C. CPGU-3-OT 1.5% Δn 0.1094 DGUQU-4-F 2.0% Δε +5.8 CCG-V-F 10.0%  ε.sub.∥ 8.8 CCP-3-1 4.5% K.sub.1 17.5 CCP-3F•F•F 10.0%  K.sub.3 19.6 CCP-5F•F•F 9.5% K.sub.3/K.sub.1 1.12 CCP-V-1 6.0% V.sub.0 1.83 V CCP-V2-1 6.5% LTS −20° C. 1000 h CCQU-2-F 8.0% LTS −30° C. 1000 h CCQU-3-F 10.0%  LTS −40° C. 1000 h PGP-2-2V 1.5% CC-3-2V1 4.0% CC-3-V1 10.5%  PP-1-2V1 5.0% PP-1-3 5.0%

(31) The mixture contains 6.0% of the compound CPGP-5-2 of formula I, and shows good LTS at −20° C., −30° C. and −40° C.

(32) VHR values

(33) The VHR values of mixtures C.sub.2, N4, N5, N6 and N7 are measured at 60C, 60 Hz/3 Hz and 1V in VHR test cell before and after light exposure for varying using a LED lamp.

(34) The results are shown in Tables 2 and 3.

(35) TABLE-US-00018 TABLE 2 VHR values before and after BL load, 60 Hz/60° C. C2 N4 N5 N6 N7 VHR/% Initial 99.2 99.1 99.3 99.3 99.4 After BL 24 h 93.8 94.0 94.1 94.3 94.5 After BL 120 h 76.7 76.6 76.7 77.5 78.8

(36) TABLE-US-00019 TABLE 3 VHR values before and after BL load, 3 Hz/60° C. C2 N4 N5 N6 N7 VHR/% Initial 93.0 93.6 94.5 94.4 94.8 After BL 24 h 70.7 71.0 72.3 73.6 74.8 After BL 120 h 21.6 21.7 22.0 23.0 24.5

(37) From Tables 2 and 3 it can be seen that the mixtures N4-N7 according to the present invention, which contain a compound of formula I, show higher VHR values than mixture C.sub.2 after backlight stress.

EXAMPLE 8

(38) To 99.95% of the LC mixture of Example 7 are added 0.05% of stabiliser S1-1.

(39) ##STR00408##

EXAMPLE 9

(40) To 99.65% of the LC mixture of Example 7 are added 0.05% of stabiliser S1-1 and 0.3% of the monomer RM-1.

(41) ##STR00409##

EXAMPLE 10

(42) To 99.7% of the LC mixture of Example 7 are added 0.3% of the monomer RM-35.

(43) ##STR00410##

EXAMPLE 11

(44) To 99.65% of the LC mixture of Example 7 are added 0.05% of stabiliser S2-1 and 0.3% of the monomer RM-64.

(45) ##STR00411##

EXAMPLE 12

(46) To 99.7% of the LC mixture of Example 6 are added 0.3% of the monomer RM-120.

(47) ##STR00412##

EXAMPLE 13

(48) To 99.699% of the LC mixture of Example 5 are added 0.3% of the monomer RM-19 and 0.001% of Irgacure 651®.

(49) ##STR00413##

EXAMPLE 14

(50) To 99.7% of the LC mixture of Example 4 are added 0.3% of the monomer RM-121.

(51) ##STR00414##

EXAMPLE 15

(52) To 99.7% of the LC mixture of Example 6 are added 0.3% of the monomer RM-122.

(53) ##STR00415##

EXAMPLE 16

(54) To 99.7% of the LC mixture of Example 7 are added 0.3% of the monomer RM-91.

(55) ##STR00416##

EXAMPLE 17

(56) To 99.98% of the LC mixture of Example 7 are added 0.02% of stabiliser S1-1.

EXAMPLE 18

(57) To 99.99% of the LC mixture of Example 7 are added 0.01% of stabiliser S2-1.

(58) ##STR00417##

EXAMPLE 19

(59) To 99.98% of the LC mixture of Example 3 are added 0.02% of stabiliser stabiliser S3-1.

(60) ##STR00418##

EXAMPLE 20

(61) To 99.95% of the LC mixture of Example 6 are added 0.05% of stabiliser S3-2.

(62) ##STR00419##

EXAMPLE 21

(63) To 99.98% of the LC mixture of Example 7 are added 0.02% of stabiliser S3-3.

(64) ##STR00420##

EXAMPLE 22

(65) To 99.7% of the LC mixture of Example 4 are added 0.3% of the monomer RM-39.

(66) ##STR00421##

(67) 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.

(68) 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. From the 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.

(69) The entire disclosures of all applications, patents and publications, cited herein and of corresponding European Application No. EP 19183112.2, filed Jun. 28, 2019, are incorporated by reference herein.