Liquid-crystalline medium

Abstract

The invention relates to the compounds of the formula I and to a liquid-crystalline medium based on a mixture of polar compounds which contains at least one compound of the formula I ##STR00001##
in which R.sup.1, ring A.sup.1, L.sup.1, L.sup.2, L.sup.3, L.sup.4, L.sup.5, L.sup.6, L.sup.7, L.sup.8, Z.sup.1 and m have the meanings indicated in claim 1 and to the use of the LC mixtures in electro-optical displays, especially for the self-aligning VA mode.

Claims

1. Liquid-crystalline medium based on a mixture of polar compounds wherein the mixture comprises at least one compound of the formula I, ##STR00394## in which R.sup.1 denotes a straight-chain alkyl or alkoxy radical having 1 to 15 C atoms, where, in addition, one or more CH.sub.2 groups in these radicals may each be replaced, independently of one another, by CC, CF.sub.2O, CHCH, , , COO, or OCO 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, ##STR00395## Z.sup.1 denotes a single bond, 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, C.sub.2F.sub.4, CHFCHF, CH.sub.2CHF, CFHCF.sub.2, CF.sub.2CHF, CHFCH.sub.2, CH.sub.2CF.sub.2O, or CHCHCH.sub.2O, L.sup.1 to L.sup.8 each, independently of one another, denote H or alkyl with 1-8 carbon atoms, provided that at least one of L.sup.1 to L.sup.8 denotes alkyl with 1-8 carbon atoms. m denotes 0, 1, 2, 3, 4, 5 or 6.

2. Liquid-crystalline medium according to claim 1 which further comprises at least one polymerisable compound.

3. Liquid-crystalline medium according to claim 1 wherein the mixture contains 0.01 to 10% by weight of the compound of the formula I based on the mixture as a whole.

4. Liquid-crystalline medium according to claim 1 wherein the at least one compound of the formula I is selected from the following group of compounds of the formula I-1 to I-9, ##STR00396## ##STR00397## in which R.sup.1, Z.sup.1 and m have the meanings as defined in claim 1 and alkyl and alkyl* each independently denote a straight-chain alkyl radical having 1 to 8 carbon atoms.

5. Liquid-crystalline medium according to claim 2, wherein the polymerisable compound is selected from the compounds of the formula M
R.sup.Ma-A.sup.M1-(Z.sup.M1-A.sup.M2).sub.m1-R.sup.MbM in which the individual radicals have the following meanings: R.sup.Ma and R.sup.Mb each, independently of one another, denote P, P-Sp-, H, halogen, SF.sub.5, NO.sub.2, an alkyl, alkenyl or alkynyl group, P denotes a polymerisable group, Sp denotes a spacer group or a single bond, A.sup.M1 and A.sup.M2 each, independently of one another, denote an aromatic, heteroaromatic, alicyclic or heterocyclic group, having 4 to 25 ring atoms, which may also encompass or contain fused rings, and which may optionally be mono- or polysubstituted by L, L denotes P, P-Sp-, F, Cl, Br, I, SF.sub.5, CN, NO.sub.2, NCO, NCS, OCN, SCN, C(O)N(R.sup.x).sub.2, C(O)Y.sup.1, C(O)R.sup.x, N(R.sup.x).sub.2, optionally substituted silyl, optionally substituted aryl having 6 to 20 C atoms, or straight-chain or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 25 C atoms, in which, in addition, one or more H atoms may be replaced by F, Cl, P or P-Sp-, Y.sup.1 denotes halogen, Z .sup.M1 denotes O, S, CO, COO, OCO, OCOO, OCH.sub.2, CH.sub.2O, SCH.sub.2, CH.sub.2S, CF.sub.2O, OCF.sub.2, CF.sub.2S, SCF.sub.2, (CH.sub.2).sub.n1, CF.sub.2CH.sub.2, CH.sub.2CF.sub.2, (CF.sub.2).sub.n1, CHCH, CFCF, CC, CHCH, COO, OCOCHCH, CR.sup.0R.sup.00 or a single bond, R.sup.0 and R.sup.00 each, independently of one another, denote H or alkyl having 1 to 12 C atoms, R.sup.x denotes P, P-Sp-, H, halogen, straight-chain, branched or cyclic alkyl having 1 to 25 C atoms, in which, in addition, one or more non-adjacent CH.sub.2 groups may be replaced by O, S, CO, COO, O CO, or OCOO in such a way that O and/or S atoms are not linked directly to one another, and in which, in addition, one or more H atoms may be replaced by F, Cl, P or P-Sp-, an optionally substituted aryl or aryloxy group having 6 to 40 C atoms, or an optionally substituted heteroaryl or heteroaryloxy group having 2 to 40 C atoms, m1 denotes 0, 1, 2, 3 or 4, and n1 denotes 1, 2, 3 or 4, where at least one group from the group R.sup.Ma, R.sup.Mb and the substituents L present denotes a group P or P-Sp- or contains at least one group P or P-Sp-.

6. Liquid-crystalline medium according to claim 5, wherein the polymerisable compound of the formula M is selected from the group of compounds of the formula M1to M41, ##STR00398## ##STR00399## ##STR00400## ##STR00401## ##STR00402## ##STR00403## ##STR00404## in which the individual radicals have the following meanings: P.sup.1, P.sup.2 and P.sup.3 each, independently of one another, denote a polymerisable group, Sp.sup.1, Sp.sup.2 and Sp.sup.3 each, independently of one another, denote a single bond or a spacer group, where, in addition, one or more of the radicals P.sup.1-Sp.sup.1 -, P.sup.2-Sp.sup.2- and P.sup.3-Sp.sup.3- may denote R.sup.aa, with the proviso that at least one of the radicals P.sup.1-Sp.sup.1 -, P.sup.2-Sp.sup.2- and P.sup.3-Sp.sup.3- present does not denote R.sup.aa, R.sup.aa denotes H, F, Cl, CN or straight-chain or branched alkyl having 1 to 25 C atoms, in which, in addition, one or more non-adjacent CH.sub.2 groups may each be replaced, independently of one another, by C(R.sup.0)C(R.sup.00), CC, N(R.sup.0), O, S, CO, COO, OCO, or OCOO in such a way that O and/or S atoms are not linked directly to one another, and in which, in addition, one or more H atoms may be replaced by F, Cl, CN or P.sup.1-Sp.sup.1-, R.sup.0 and R.sup.00 each, independently of one another and identically or differently on each occurrence, denote H or alkyl having 1 to 12 C atoms, R.sup.y and R.sup.z each, independently of one another, denote H, F, CH.sub.3 or CF.sub.3, X.sup.1, X.sup.2 and X.sup.3 each, independently of one another, denote COO, OCO or a single bond, Z.sup.1 denotes O, CO, C(R.sup.yR.sup.z)or CF.sub.2CF.sub.2, Z.sup.2 and Z.sup.3 each, independently of one another, denote COO, OCO, CH.sub.2O, OCH.sub.2, CF.sub.2O, OCF.sub.2 or (CH.sub.2).sub.n, where n is 2, 3 or 4, L on each occurrence, identically or differently, denotes F, Cl, CN or straight-chain or branched, optionally monoor polyfluorinated alkyl, alkoxy, alkenyl, alkynyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 12 C atoms, L and L each, independently of one another, denote H, F or Cl, r denotes 0, 1, 2, 3 or 4, s denotes 0, 1, 2 or 3, t denotes 0, 1 or 2, and x denotes 0 or 1.

7. Liquid-crystalline medium according to claim 1, wherein the medium additionally contains one or more compounds selected from the group of the compounds of the formulae IIA, IIB and IIC ##STR00405## in which R.sup.2A, R.sup.2Band R.sup.2C each, independently of one another, denote H, an alkyl or alkenyl radical having up to 15 C atoms which is unsubstituted, monosubstituted by CN or CF.sub.3 or at least monosubstituted by halogen, where, in addition, one or more CH.sub.2 groups in these radicals may be replaced by O, S, ##STR00406## CC, CF.sub.2O, OCF.sub.2, , OCO or OCOin such a way that O atoms are not linked directly to one another, L.sup.1-4 each, independently of one another, denote F, Cl, CF.sub.3 or OCHF.sub.2 Z.sup.2 and Z.sup.2 each, independently of one another, denote a single bond, 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, or CHCHCH.sub.2O, (O)C.sub.vH.sub.2v+1 denotes OC.sub.vH.sub.2v+1 or C.sub.vH.sub.2v+1, p denotes 0, 1 or 2, q denotes 0 or 1, and v denotes 1 to 6.

8. Liquid-crystalline medium according to claim 1, wherein the medium additionally contains one or more compounds of the formula III, ##STR00407## in which R.sup.31 and R.sup.32 each, independently of one another, denote a straight-chain alkyl, alkoxyalkyl or alkoxy radical having up to 12 C atoms, and ##STR00408## and Z.sup.3 denotes a single bond, 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, C.sub.4H.sub.8, or CFCF.

9. Liquid-crystalline medium according to claim 1, wherein the medium additionally contains at least one compound of the formulae L-1 to L-11, ##STR00409## ##STR00410## in which R, R.sup.1 and R.sup.2 each, independently of one another, denote H, an alkyl having 1-6C atoms or alkenyl radical having up to 15 C atoms which is unsubstituted, monosubstituted by CN or CF.sub.3 or at least monosubstituted by halogen, where, in addition, one or more CH.sub.2 groups in these radicals may be replaced by O, S, ##STR00411## CC, CF.sub.2O, OCF.sub.2, CHCH, OCOor OCO in such a way that O atoms are not linked directly to one another, (O)-alkyl denotes O-alkyl or alkyl, and s denotes 1 or 2.

10. Liquid-crystalline medium according to claim 1, wherein the medium additionally comprises one or more terphenyls of the formulae T-1 to T-23, ##STR00412## ##STR00413## ##STR00414## ##STR00415## in which R denotes a straight-chain alkyl or alkoxy radical having 1-7 C atoms, (O)C.sub.mH.sub.2m+1 denotes OC.sub.mH.sub.2m+1 or C.sub.mH.sub.2m+1, m denotes 0, 1, 2, 3, 4, 5 or 6, and n denotes 0, 1, 2, 3 or 4.

11. Liquid-crystalline medium according to claim 1, wherein the medium additionally comprises one or more compounds of the formulae O-1 to O-17, ##STR00416## ##STR00417## in which R.sup.1 and R.sup.2 each, independently of one another, denote H, an alkyl or alkenyl radical having up to 15 C atoms which is unsubstituted, monosubstituted by CN or CF.sub.3 or at least monosubstituted by halogen, where, in addition, one or more CH.sub.2 groups in these radicals may be replaced by O, S, ##STR00418## CC, CF.sub.2O, OCF.sub.2, CHCH, OCO or OCO in such a way that O atoms are not linked directly to one another.

12. Liquid-crystalline medium according to claim 1, wherein the medium additionally contains one or more indane compounds of the formula In, ##STR00419## in which R.sup.11, R.sup.12, R.sup.13 denote a straight-chain alkyl, alkoxy, alkoxyalkyl or alkenyl radical having 1-5 C atoms, R.sup.12 and R.sup.13 additionally also denote H or halogen, ##STR00420## and i denotes 0, 1 or 2.

13. Liquid-crystalline medium according to claim 1, wherein the medium additionally contains one or more UV absorbers, antioxidants, nanoparticles or free-radical scavengers.

14. Process for the preparation of a liquid-crystalline medium according to claim 1, which comprises mixing at least one self-aligning compound of the formula I with at least two liquid-crystalline compounds, and optionally with at least one polymerisable compound and optionally one or more additives.

15. A method for preparing an electro-optical display which comprises incorporating a liquid crystal medium according to claim 1 in an electro-optical display.

16. A method according to claim 15 wherein said liquid crystal medium is incorporated in an electro-optical display to provide a self-aligning VA mode.

17. Electro-optical display having active-matrix or passive-matrix addressing, which comprises, as dielectric, a liquid-crystalline medium according to claim 1.

18. Electro-optical display according to claim 17, characterised in that it is a VA, PM-VA, PSA or PS-VA display.

19. A compound of the formula I ##STR00421## in which R.sup.1 denotes a straight-chain alkyl or alkoxy radical having 1 to 15 C atoms, where, in addition, one or more CH.sub.2 groups in these radicals may each be replaced, independently of one another, by CC, CF.sub.2O, CHCH, ##STR00422## O, COO, or OCO 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, ##STR00423## Z.sup.1 denotes a single bond, 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, C.sub.2F.sub.4, CHFCHF, CH.sub.2CHF, CFHCF.sub.2, CF.sub.2CHF, CHFCH.sub.2, CH.sub.2CF.sub.2O, or CHCHCH.sub.2O, L.sup.1 to L.sup.8 each, independently of one another, denote H or alkyl with 1-8 carbon atoms, provided that at least one of L.sup.1 to L.sup.8 denotes alkyl with 1-8 carbon atoms, and m denotes 0, 1, 2, 3, 4, 5 or 6.

20. Liquid-crystalline medium according to claim 5, wherein: at least one of the radicals R.sup.Ma and R.sup.Mb denotes or contains a group P or P-Sp-, A.sup.M1 and A.sup.M2 each, independently of one another, denote an aromatic, or alicyclic group, having 4 to 25 ring C atoms, which may also encompass or contain fused rings, and which may optionally be mono- or polysubstituted by L, and L denotes P, P-Sp- , H, halogen, SF.sub.5, NO.sub.2, an alkyl, alkenyl or alkynyl group.

21. Liquid-crystalline medium according to claim 6, wherein: P.sup.1, P.sup.2 and P.sup.3 each, independently of one another, denote an acrylate, methacrylate, fluoroacrylate, oxetane, vinyl, vinyloxy or epoxide group, Sp.sup.1, Sp.sup.2and Sp.sup.3 each, independently of one another, denote a single bond, (CH.sub.2).sub.p1, (CH.sub.2).sub.p1O, (CH.sub.2).sub.p1COO or (CH.sub.2).sub.p1OCOO, in which p1 is an integer from 1 to 12, and where the linking to the adjacent ring in the last-mentioned groups takes place via the O atom, where, in addition, one or more of the radicals P.sup.1-Sp.sup.1-, P.sup.2-Sp.sup.2- and P.sup.3-Sp.sup.3- may denote R.sup.aa, with the proviso that at least one of the radicals P.sup.1-Sp.sup.1-, P.sup.2-Sp.sup.2- and P.sup.3-Sp.sup.3- present does not denote R.sup.aa, and R.sup.aa denotes a straight-chain or branched, optionally mono- or polyfluorinated alkyl, alkoxy, alkenyl, alkynyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy group having 1 to 12 C atoms, where the alkenyl and alkynyl radicals have at least two C atoms and the branched radicals have at least three C atoms.

22. A compound according to claim 19, wherein at least one of L.sup.1 to L.sup.8 denotes straight-chain alkyl with 2-8 carbon atoms.

23. A liquid crystalline medium according to claim 1, wherein the mixture comprises at least one compound of formula I wherein at least one of L.sup.1 to L.sup.8 denotes straight-chain alkyl with 2-8 carbon atoms.

24. A liquid crystalline medium according to claim 1, wherein the at least one compound of formula I is one of the following compounds ##STR00424##

25. A liquid crystalline medium according to claim 1, wherein the at least one compound of formula I is the following compound: ##STR00425##

Description

EXAMPLES

(1) The following examples are intended to explain the invention without restricting it. In the examples, m.p. denotes the melting point and C denotes the clearing point of a liquid-crystalline substance in degrees Celsius; boiling points are denoted by b.p. Furthermore:

(2) C denotes crystalline solid state, S denotes smectic phase (the index denotes the phase type), N denotes nematic state, Ch denotes cholesteric phase, I denotes isotropic phase, T.sub.g denotes glass transition temperature. The number between two symbols indicates the conversion temperature in degrees Celsius.

(3) Conventional work-up means: water is added, the mixture is extracted with methylene chloride, the phases are separated, the organic phase is dried and evaporated, and the product is purified by crystallisation and/or chromatography.

Example 1

Synthesis of 3-[2-Ethyl-4-(4-pentyl-cyclohexyl)-biphenyl-4-yl]-propan-1-ol 1

(4) ##STR00367##

1.1) Synthesis of 4-Bromo-2-ethyl-4-(4-pentyl-cyclohexyl)-biphenyl A1

(5) ##STR00368##

(6) 364.7 mmol 4-bromo-2-ethyl-1-iodo-benzene are solved in mixture of 580 ml toluene and 330 ml water. 912 mmol Na.sub.2CO.sub.3 are added and the mixture is heated to 80 C. and 9.26 mmol tetrakis-(triphenylphosphin)-palladium(0) is added and immediately 4-(trans-4-pentylcyclohexyl)phenyl boronic acid solved in 210 ml ethanol is added within 15 min. and the reaction mixture is refluxed for 18 h. After cooling to room temperature (RT) 100 ml water and 100 ml methyl-tert-butyl ether (MTBE) are added and the phases are separated. The organic phase is dried over sodium sulphate, filtered and evaporated under vacuum. The crude product is purified via column filtration over silica gel with n-heptane and the product fractions are evaporated under vacuum and crystallized at 30 C. from n-heptane to give 65 g (42%) of A1 as a white crystalline solid.

1.2) Synthesis of tert-Butyl-{3-[2-ethyl-4-(4-pentyl-cyclohexyl)-biphenyl-4-yl]-prop-2-ynyloxy}-dimethyl-silane B1

(7) ##STR00369##

(8) 86.8 mmol bromide A1 and 260.5 mmol tert-butyl-dimethyl-prop-2-ynyloxy-silane are solved in 610 ml diisopropylamine and 4.34 mmol palladium acetate and 4.34 mmol copper(I) iodide is added and the mixture is stirred at 80 C. for 3 h. The reaction mixture is cooled to room temperature (RT), water is added and the product is extracted repeatedly with MTBE, washed with brine, dried over sodium sulphate, filtered and evaporated under vacuum. The crude product is purified via column filtration over silica gel with n-heptane/chlorobutane (1:1) to give 33 g of B1.

1.3) Synthesis of tert-Butyl-{3-[2-ethyl-4-(4-pentyl-cyclohexyl)-biphenyl-4-yl]-propoxy}-dimethyl-silane C1

(9) ##STR00370##

(10) 89.1 mmol alkine B1 is solved in 456 ml tetrahydrofuran (THF) and 5.0 g sponge nickel catalyst (watery/Jhonson Matthey) is added and the reaction mixture is stirred under an hydrogen atmosphere at room temperature and normal pressure for 20 h. The reaction mixture is filtered and with a mixture of n-heptane and chlorobutane (1:1) purified over silica gel to give 43 g (94%) of C1.

1.4) Synthesis of 3-[2-Ethyl-4-(4-pentyl-cyclohexyl)-biphenyl-4-yl]-propan-1-ol 1

(11) ##STR00371##

(12) 83.4 mmol of compound C1 are solved in 507 ml THF and the reaction mixture is then cooled to 2 C. At this temperature 47.9 ml (95.9 mmol/2N) HCl are added slowly and the mixture is then stirred at 2-4 C. for further 60 min. and is then allowed to reach room temperature within 3 h. The reaction mixture is then carefully neutralized with NaHCO.sub.3, extracted with MTBE and the combined organic phases are dried over sodium sulphate, filtered and evaporated under vacuum. The crude product is purified vie column chromatography with n-heptane/ethylacetat (1:1) and the obtained product is crystallized from n-heptane at 30 C. to give 1 as a white solid.

(13) Phases: T.sub.g40 K 49 N (29.3) I

(14) Mp.: 49 C.

(15) MS: EI (392.3)

Example 2

Synthesis of 2-(2-Ethyl-4-pentyl-[1,1;4,1]terphenyl-4-yl)-ethanol 2

(16) ##STR00372##

2.1) Synthesis of 2-[4-(4,4,5,5-Tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]-ethanol A2

(17) ##STR00373##

(18) 99.5 mmol 2-(4-bromo-phenyl)-ethanol, 109 mmol bis-(pinacolato)-diboron, 330 mmol potassium acetate and 3.4 mmol PdCl.sub.2dppf are dissolved in 355 ml 1,4-dioxane and refluxed for 18 h. The reaction mixture is cooled to room temperature and 300 ml water is added. The mixture is extracted with methyl-tert-butyl ether (MTBE), washed with brine, dried over sodium sulphate, filtered and evaporated under vacuum. The crude product is purified via silica gel chromatography (toluene/ethyl acetate 4:1) to give 22 g of A2 as a yellow oil.

2.2) Synthesis of 2-(4-Bromo-2-ethyl-biphenyl-4-yl)-ethanol B2

(19) ##STR00374##

(20) 236 mmol sodium carbonate is solved in 175 ml water and 75 ml ethanol. 95.2 mmol 4-bromo-2-ethyl-1-iodo-benzene, 95.0 mmol boronic ester A2 are dissolved in 375 ml toluene and added to the reaction mixture. After adding Pd(PPh.sub.3).sub.4 to the mixture it is refluxed for 5.5 h and cooled to room temperature. The organic phase is separated and the water phase is extracted with ethyl acetate. The combined organic phases are washed with brine, dried over sodium sulphate, filtered and evaporated under vacuum. The crude product is purified via silica gel chromatography (n-heptane/ethyl acetate 8:2) and (toluene/ethyl acetate 95:5) to give 24.5 g (80%) of B2.

2.3) Synthesis of 2-(2-Ethyl-4-pentyl-[1,1,4,1]terphenyl-4-yl)-ethanol 2

(21) ##STR00375##

(22) 101 mmol sodium metaborate tetrahydrate are solved in 215 ml water and added with 1.34 mmol Pd(PPh.sub.3).sub.2Cl.sub.2, 0.065 ml hydrazinium hydroxide, 67.0 mmol) of bromide B2 and 25 ml THF. The mixture is stirred for 5 min and then 67.2 mmol 4-(pentylphenyl) boronic acid in 50 ml THF is added. The reaction mixture is refluxed for 16 h and cooled to room temperature. The reaction product is extracted with methyl-tert.-butyl ether (MTBE) and the organic layer is washed with brine, dried over sodium sulphate, filtered and evaporated under vacuum. The crude product is purified via silica gel chromatograpy (toluene/n-heptane 1:1) and afterwards crystallized from n-heptane to give 2 as white crystals.

(23) Phases: T.sub.g25 K 67 N (14) I

(24) Mp: 67 C.

Example 3

Synthesis of 2-{2,2-Diethyl-4-[2-(4-pentyl-phenyl)-ethyl]-biphenyl-4-yl}-ethanol 3

(25) ##STR00376##

3.1) Synthesis of 4,4-Dibromo-2,2-diethyl-biphenyl A3

(26) ##STR00377##

(27) 189 mmol Na.sub.2CO.sub.3 and 79.0 mmol 4-bromo-2-ethyl-1-iodo-benzene is solved in 70 ml water and 125 ml toluene. The reaction mixture is heated up to 75 C. and 2.42 mmol tetrakis(triphenylphosphin)-palladium(0) and immediately afterwards a solution of 79.0 mmol 4-bromo-2-ethylphenyl boronic acid in 25 ml ethanol is added within 15 min. to the reaction mixture and then stirred for 6 h at reflux. The mixture is cooled to room temperature (RT) and water and toluene are added and the phases are separated. The organic phase is washed with brine and dried over sodium sulphate, filtered and evaporated under vacuum. The crude product is purified via column chromatograpy with n-heptane over silica gel to give 27.3 g (87%) of A3.

3.2) Synthesis of 4-Bromo-2,2-diethyl-4-(4-pentyl-phenylethynyl)-biphenyl B3

(28) ##STR00378##

(29) 69.0 mmol of bromide A3 are solved in 75 ml triethylamine and 2.137 mmol) bis(triphenylphosphin)-palladium(II)-chlorid and 2.1 mmol copper(I) iodide are added. The reaction mixture is heated up to 75 C. and a solution of 70.0 mmol 1-ethynyl-4-pentyl-benzene solved in 50 ml triethylamine is added within 15 min and the mixture is stirred for 18 h under reflux. The mixture is cooled to RT and water and MTBE is added. The organic phase is separated, washed with brine, dried over sodium sulphate, filtered and evaporated under vacuum. The crude product is purified via column chromatography with n-heptane over silica gel to give 11.4 g (33%) of B3.

3.3) Synthesis of 2-[2,2-Diethyl-4-(4-pentyl-phenylethynyl)-biphenyl-4-yl]-ethanol C3

(30) ##STR00379##

(31) 23.0 mmol of bromide B3 is solved in 30 ml THF and is cooled to 78 C. 27.0 mmol of n-buthyllithium (1.6 M in hexane) is then added dropwise and the reaction mixture is stirred at 78 C. for 30 min. 32.0 mmol ethylenoxide solved in 10 ml cooled THF is then added and 3.50 ml (28.0 mmol) BF.sub.3*OEt.sub.2 solved in 20 ml cooled THF is the added cautiously (exothermic reaction) at 78 C. The reaction mixture is the allowed to reach RT over 18 h and is poured cautiously into ice water. The product is extracted with MTBE, washed with brine, dried over sodium sulphate, filtered and evaporated under vacuum. The crude product is purified vie column chromatography with dichloromethane over silica gel to give C3.

3.4) Synthesis of 2-{2,2-Diethyl-4-[2-(4-pentyl-phenyl)-ethyl]-biphenyl-4-yl}-ethanol 3

(32) ##STR00380##

(33) 17.5 mmol of alkine C3 is solved in 80 ml tetrahydrofuran and 2 g PdC-5% (54% water/Degussa) is added. The reaction mixture is then stirred under hydrogen at room temperature for 18 h at normal pressure. The mixture is filtered and evaporated under vacuum. The crude product is then purified via column chromatography with toluene/MTBE (9:1) over silica gel to give 3 as a yellow oil.

(34) The following compounds are synthesized accordingly to the above

(35) ##STR00381##

(36) mentioned examples:

(37) In the following examples V.sub.0 denotes the threshold voltage, capacitive [V] at 20 C. n denotes the optical anisotropy measured at 20 C. and 589 nm denotes the dielectric anisotropy at 20 C. and 1 kHz cl.p. denotes the clearing point [ C.] K.sub.1 denotes the elastic constant, splay deformation at 20 C. [pN] K.sub.3 denotes the elastic constant, bend deformation at 20 C. [pN] .sub.1 denotes the rotational viscosity measured at 20 C. [mPa.Math.s], determined by the rotation method in a magnetic field LTS denotes the low-temperature stability (nematic phase), determined in test cells.

(38) The display used for measurement of the threshold voltage has two plane-parallel outer plates at a separation of 20 m and electrode layers with overlying alignment layers of JALS-2096 on the insides of the outer plates, which effect a homeotropic alignment of the liquid crystals.

(39) All concentrations in this application relate to the corresponding mixture or mixture component, unless explicitly indicated otherwise. All physical properties are determined as described in Merck Liquid Crystals, Physical Properties of Liquid Crystals, status November 1997, Merck KGaA, Germany, and apply for a temperature of 20 C., unless explicitly indicated otherwise.

(40) Unless indicated otherwise, parts or percent data denote parts by weight or percent by weight.

MIXTURE EXAMPLES

(41) For the production of the examples according to the present invention the following host mixtures H1 to H46 are used:

(42) H1: Nematic Host-Mixture

(43) TABLE-US-00006 CY-3-O2 15.50% Clearing point [ C.]: 75.1 CCY-3-O3 8.00% n [589 nm, 20 C.]: 0.098 CCY-4-O2 10.00% [1 kHz, 20 C.]: 3.0 CPY-2-O2 5.50% .sub. [1 kHz, 20 C.]: 3.4 CPY-3-O2 11.50% .sub. [1 kHz, 20 C.]: 6.4 CCH-34 9.25% K.sub.1 [pN, 20 C.]: 13.1 CCH-23 24.50% K.sub.3 [pN, 20 C.]: 13.3 PYP-2-3 8.75% .sub.1 [mPa .Math. s, 20 C.]: 113 PCH-301 7.00% V.sub.0 [20 C., V]: 2.22

(44) H2: Nematic Host-Mixture

(45) TABLE-US-00007 CY-3-O4 14.00% Clearing point [ C.]: 80.0 CCY-3-O2 9.00% n [589 nm, 20 C.]: 0.090 CCY-3-O3 9.00% [1 kHz, 20 C.]: 3.3 CPY-2-O2 10.00% .sub. [1 kHz, 20 C.]: 3.4 CPY-3-O2 10.00% .sub. [1 kHz, 20 C.]: 6.7 CCY-3-1 8.00% K.sub.1 [pN, 20 C.]: 15.1 CCH-34 9.00% K.sub.3 [pN, 20 C.]: 14.6 CCH-35 6.00% .sub.1 [mPa .Math. s, 20 C.]: 140 PCH-53 10.00% V.sub.0 [20 C., V]: 2.23 CCH-301 6.00% CCH-303 9.00%

(46) H3: Nematic Host-Mixture

(47) TABLE-US-00008 CC-3-V1 9.00% Clearing point [ C.]: 74.7 CCH-23 18.00% n [589 nm, 20 C.]: 0.098 CCH-34 3.00% [1 kHz, 20 C.]: 3.4 CCH-35 7.00% .sub. [1 kHz, 20 C.]: 3.5 CCP-3-1 5.50% .sub. [1 kHz, 20 C.]: 6.9 CCY-3-O2 11.50% K.sub.1 [pN, 20 C.]: 14.9 CPY-2-O2 8.00% K.sub.3 [pN, 20 C.]: 15.9 CPY-3-O2 11.00% .sub.1 [mPa .Math. s, 20 C.]: 108 CY-3-O2 15.50% V.sub.0 [20 C., V]: 2.28 PY-3-O2 11.50%

(48) H4: Nematic Host-Mixture

(49) TABLE-US-00009 CC-3-V 37.50% Clearing point [ C.]: 74.8 CC-3-V1 2.00% n [589 nm, 20 C.]: 0.099 CCY-4-O2 14.50% [1 kHz, 20 C.]: 2.9 CPY-2-O2 10.50% .sub. [1 kHz, 20 C.]: 3.7 CPY-3-O2 9.50% .sub. [1 kHz, 20 C.]: 6.6 CY-3-O2 15.00% K.sub.1 [pN, 20 C.]: 12.2 CY-3-O4 4.50% K.sub.3 [pN, 20 C.]: 13.4 PYP-2-4 5.50% .sub.1 [mPa .Math. s, 20 C.]: 92 PPGU-3-F 1.00% V.sub.0 [20 C., V]: 2.28

(50) H5: Nematic Host-Mixture

(51) TABLE-US-00010 CCH-23 20.00% Clearing point [ C.]: 74.8 CCH-301 6.00% n [589 nm, 20 C.]: 0.105 CCH-34 6.00% [1 kHz, 20 C.]: 3.2 CCP-3-1 3.00% .sub. [1 kHz, 20 C.]: 3.5 CCY-3-O2 11.00% .sub. [1 kHz, 20 C.]: 6.8 CPY-2-O2 12.00% K.sub.1 [pN, 20 C.]: 12.7 CPY-3-O2 11.00% K.sub.3 [pN, 20 C.]: 13.6 CY-3-O2 14.00% .sub.1 [mPa .Math. s, 20 C.]: 120 CY-3-O4 4.00% V.sub.0 [20 C., V]: 2.16 PCH-301 4.00% PYP-2-3 9.00%

(52) H6: Nematic Host-Mixture

(53) TABLE-US-00011 CC-4-V 17.00% Clearing point [ C.]: 106.1 CCP-V-1 15.00% n [589 nm, 20 C.]: 0.120 CCPC-33 2.50% [1 kHz, 20 C.]: 3.6 CCY-3-O2 4.00% .sub. [1 kHz, 20 C.]: 3.5 CCY-3-O3 5.00% .sub. [1 kHz, 20 C.]: 7.0 CCY-4-O2 5.00% K.sub.1 [pN, 20 C.]: 16.8 CLY-3-O2 3.50% K.sub.3 [pN, 20 C.]: 17.3 CLY-3-O3 2.00% .sub.1 [mPa .Math. s, 20 C.]: 207 CPY-2-O2 8.00% V.sub.0 [20 C., V]: 2.33 CPY-3-O2 10.00% CY-3-O4 17.00% PYP-2-3 11.00%

(54) H7: Nematic Host-Mixture

(55) TABLE-US-00012 CY-3-O2 15.00% Clearing point [ C.]: 75.5 CCY-4-O2 9.50% n [589 nm, 20 C.]: 0.108 CCY-5-O2 5.00% [1 kHz, 20 C.]: 3.0 CPY-2-O2 9.00% .sub. [1 kHz, 20 C.]: 3.5 CPY-3-O2 9.00% .sub. [1 kHz, 20 C.]: 6.5 CCH-34 9.00% K.sub.1 [pN, 20 C.]: 12.9 CCH-23 22.00% K.sub.3 [pN, 20 C.]: 13.0 PYP-2-3 7.00% .sub.1 [mPa .Math. s, 20 C.]: 115 PYP-2-4 7.50% V.sub.0 [20 C., V]: 2.20 PCH-301 7.00%

(56) H8: Nematic Host-Mixture

(57) TABLE-US-00013 CY-3-O2 15.00% Clearing point [ C.]: 74.7 CY-5-O2 6.50% n [589 nm, 20 C.]: 0.108 CCY-3-O2 11.00% [1 kHz, 20 C.]: 3.0 CPY-2-O2 5.50% .sub. [1 kHz, 20 C.]: 3.6 CPY-3-O2 10.50% .sub. [1 kHz, 20 C.]: 6.6 CC-3-V 28.50% K.sub.1 [pN, 20 C.]: 12.9 CC-3-V1 10.00% K.sub.3 [pN, 20 C.]: 15.7 PYP-2-3 12.50% .sub.1 [mPa .Math. s, 20 C.]: 97 PPGU-3-F 0.50% V.sub.0 [20 C., V]: 2.42

(58) H9: Nematic Host-Mixture

(59) TABLE-US-00014 CCH-35 9.50% Clearing point [ C.]: 79.1 CCH-501 5.00% n [589 nm, 20 C.]: 0.091 CCY-2-1 9.50% [1 kHz, 20 C.]: 3.6 CCY-3-1 10.50% .sub. [1 kHz, 20 C.]: 3.5 CCY-3-O2 10.50% .sub. [1 kHz, 20 C.]: 7.1 CCY-5-O2 9.50% K.sub.1 [pN, 20 C.]: 14.6 CPY-2-O2 12.00% K.sub.3 [pN, 20 C.]: 14.5 CY-3-O4 9.00% .sub.1 [mPa .Math. s, 20 C.]: 178 CY-5-O4 11.00% V.sub.0 [20 C., V]: 2.12 PCH-53 13.50%

(60) H10: Nematic Host-Mixture

(61) TABLE-US-00015 Y-4O-O4 3.00% Clearing point [ C.]: 100 PYP-2-3 10.00% n [589 nm, 20 C.]: 0.1603 PYP-2-4 10.00% [1 kHz, 20 C.]: 0.7 CC-3-V 25.00% .sub. [1 kHz, 20 C.]: 3.1 CCP-V-1 11.00% .sub. [1 kHz, 20 C.]: 3.8 CCP-V2-1 10.00% BCH-32 5.00% CVCP-1V-O1 5.00% PTP-3O2FF 3.00% CPTP-3O2FF 2.50% PTP-101 5.00% PTP-201 5.00% CPTP-301 5.00% PPTUI-3-2 0.50%

(62) stabilized with 0.01% of the compound of the formula

(63) ##STR00382##

(64) H11: Nematic Host-Mixture

(65) TABLE-US-00016 CY-3-O2 15.00% Clearing point [ C.]: 91 CY-3-O4 20.00% n [589 nm, 20 C.]: 0.0909 CY-5-O2 10.00% .sub. [1 kHz, 20 C.]: 4.1 CY-5-O4 7.00% .sub. [1 kHz, 20 C.]: 10.1 CCY-3-O2 6.50% [1 kHz, 20 C.]: 6.0 CCY-3-O3 6.50% .sub.1 [mPa .Math. s, 20 C.]: 310 CCY-4-O2 6.50% CCY-5-O2 6.50% CPY-2-O2 3.00% CH-33 3.00% CH-35 3.00% CH-43 3.00% CCPC-33 5.00% CCPC-34 5.00%

(66) H12: Nematic Host-Mixture

(67) TABLE-US-00017 CY-3-O2 15.00% Clearing point [ C.]: 91 CY-3-O4 20.00% n [589 nm, 20 C.]: 0.1099 CY-5-O2 10.00% .sub. [1 kHz, 20 C.]: 4.2 CCY-3-O2 6.50% .sub. [1 kHz, 20 C.]: 10.3 CCY-3-O3 6.00% [1 kHz, 20 C.]: 6.1 CCY-4-O2 6.00% .sub.1 [mPa .Math. s, 20 C.]: 297 CCY-5-O2 6.00% CPY-2-O2 8.00% CPY-3-O2 8.00% CC-4-V 2.50% CCP-V-1 3.50% CPTP-3-1 2.50% CCPC-33 4.00% CCPC-34 2.00%

(68) H13: Nematic Host-Mixture

(69) TABLE-US-00018 CY-3-O2 15.00% Clearing point [ C.]: 91 CY-3-O4 20.00% n [589 nm, 20 C.]: 0.0897 CY-5-O2 6.00% .sub. [1 kHz, 20 C.]: 3.7 CCY-3-O2 6.00% .sub. [1 kHz, 20 C.]: 8.0 CCY-3-O3 6.00% [1 kHz, 20 C.]: 4.3 CCY-4-O2 6.00% .sub.1 [mPa .Math. s, 20 C.]: 204 CPY-2-O2 6.00% CC-4-V 15.00% CCP-V2-1 6.50% CCPC-33 4.50% CCPC-34 4.50% CCPC-35 4.50%

(70) H14: Nematic Host-Mixture

(71) TABLE-US-00019 CY-3-O2 15.00% Clearing point [ C.]: 91 CY-3-O4 20.00% n [589 nm, 20 C.]: 0.1106 CCY-3-O2 6.00% .sub. [1 kHz, 20 C.]: 3.9 CCY-3-O3 6.00% .sub. [1 kHz, 20 C.]: 8.4 CCY-4-O2 6.00% [1 kHz, 20 C.]: 4.5 CCY-5-O2 2.00% .sub.1 [mPa .Math. s, 20 C.]: 202 CPY-2-O2 8.00% CPY-3-O2 8.00% CC-4-V 8.00% CCP-V-1 12.00% CCP-V2-1 5.00% CPTP-3-1 4.00%

(72) H15: Nematic Host-Mixture

(73) TABLE-US-00020 CY-3-O2 15.00% Clearing point [ C.]: 95 CY-3-O4 20.00% n [589 nm, 20 C.]: 0.0974 CY-5-O2 8.50% .sub. [1 kHz, 20 C.]: 4.1 CCY-3-O2 6.50% .sub. [1 kHz, 20 C.]: 9.9 CCY-3-O3 6.50% [1 kHz, 20 C.]: 5.8 CCY-4-O2 6.50% K.sub.1 [pN, 20 C.]: 14.3 CCY-5-O2 6.50% K.sub.3 [pN, 20 C.]: 16.8 CPY-2-O2 7.50% V.sub.0 [pN, 20 C.]: 1.79 CPY-3-O2 3.50% .sub.1 [mPa .Math. s, 20 C.]: 292 CC-4-V 6.00% CH-33 3.50% CCPC-33 5.00% CCPC-34 5.00%

(74) H16: Nematic Host-Mixture

(75) TABLE-US-00021 CY-3-O2 15.00% Clearing point [ C.]: 95 CY-3-O4 20.00% n [589 nm, 20 C.]: 0.1126 CY-5-O2 2.00% .sub. [1 kHz, 20 C.]: 4.0 CCY-3-O2 6.50% .sub. [1 kHz, 20 C.]: 9.8 CCY-3-O3 6.50% [1 kHz, 20 C.]: 5.8 CCY-4-O2 6.50% K.sub.1 [pN, 20 C.]: 15.1 CCY-5-O2 6.50% K.sub.3 [pN, 20 C.]: 17.8 CPY-2-O2 8.00% V.sub.0 [pN, 20 C.]: 1.84 CPY-3-O2 8.00% .sub.1 [mPa .Math. s, 20 C.]: 270 CPTP- 4.00% CC-4-V 5.00% CCP-V-1 10.50% CCPC-33 1.50%

(76) H17: Nematic Host-Mixture

(77) TABLE-US-00022 CY-3-O2 12.00% Clearing point [ C.]: 95 CY-3-O4 16.00% n [589 nm, 20 C.]: 0.0972 CCY-3-O2 6.50% .sub. [1 kHz, 20 C.]: 3.6 CCY-3-O3 6.50% .sub. [1 kHz, 20 C.]: 7.6 CCY-4-O2 6.50% [1 kHz, 20 C.]: 4.0 CCY-5-O2 6.00% K.sub.1 [pN, 20 C.]: 14.9 CPY-2-O2 6.00% K.sub.3 [pN, 20 C.]: 17.0 CPY-3-O2 5.50% V.sub.0 [pN, 20 C.]: 2.17 CC-4-V 15.00% .sub.1 [mPa .Math. s, 20 C.]: 180 CCP-V-1 10.00% CCP-V2-1 10.00%

(78) stabilized with 0.03% of

(79) ##STR00383##

(80) H18: Nematic Host-Mixture

(81) TABLE-US-00023 CY-3-O2 11.00% Clearing point [ C.]: 95 CY-3-O4 16.00% n [589 nm, 20 C.]: 0.1121 CCY-3-O2 6.50% .sub. [1 kHz, 20 C.]: 3.7 CCY-3-O3 6.00% .sub. [1 kHz, 20 C.]: 7.7 CCY-4-O2 6.00% [1 kHz, 20 C.]: 4.0 CPY-2-O2 8.00% K.sub.1 [pN, 20 C.]: 14.8 CPY-3-O2 8.00% K.sub.3 [pN, 20 C.]: 16.2 CPTP-3O2FF 5.00% V.sub.0 [pN, 20 C.]: 2.13 CC-4-V 16.00% .sub.1 [mPa .Math. s, 20 C.]: 179 CCP-V-1 12.00% BCH-32 5.50%

(82) H19: Nematic Host-Mixture

(83) TABLE-US-00024 CY-3-O2 3.50% Clearing point [ C.]: 102.5 CY-3-O4 16.00% n [589 nm, 20 C.]: 0.1112 CY-5-O2 8.75% .sub. [1 kHz, 20 C.]: 3.8 CCY-3-O2 6.00% .sub. [1 kHz, 20 C.]: 8.8 CCY-3-O3 6.00% [1 kHz, 20 C.]: 5.0 CCY-4-O2 6.00% K.sub.1 [pN, 20 C.]: 15.0 CCY-5-O2 6.00% K.sub.3 [pN, 20 C.]: 18.7 CPY-2-O2 8.00% V.sub.0 [pN, 20 C.]: 2.04 CPY-3-O2 8.50% .sub.1 [mPa .Math. s, 20 C.]: 280 CC-4-V 3.00% CCP-V-1 7.25% CCP-V2-1 3.25% CCPC-33 2.75% CY-5-O4 6.50% CC-5-V 3.50% CCPC-34 2.00% CPTP-301 1.75% PTP-102 1.25%

(84) H20: Nematic Host-Mixture

(85) TABLE-US-00025 CCY-5-O2 5.25% Clearing point [ C.]: 102 CPY-2-O2 11.75% n [589 nm, 20 C.]: 0.1133 CPY-3-O2 11.75% .sub. [1 kHz, 20 C.]: 4.1 CC-5-V 3.00% .sub. [1 kHz, 20 C.]: 10.5 CCPC-33 1.50% [1 kHz, 20 C.]: 6.4 CCPC-34 1.50% K.sub.1 [pN, 20 C.]: 15.4 CCPC-35 1.00% K.sub.3 [pN, 20 C.]: 18.8 CY-3-O2 8.50% V.sub.0 [pN, 20 C.]: 1.81 CY-3-O4 23.00% .sub.1 [mPa .Math. s, 20 C.]: 367 CCY-3-O2 7.25% CCY-3-O3 6.75% CCY-4-O2 6.75% CY-5-O4 4.50% CCY-3-1 4.00% CCP-V-1 2.00% CBC-33F 1.50%

(86) H21: Nematic Host-Mixture

(87) TABLE-US-00026 CY-3-O2 6.00% Clearing point [ C.]: 102 CY-3-O4 14.00% n [589 nm, 20 C.]: 0.0898 CCY-3-O2 4.00% .sub. [1 kHz, 20 C.]: 3.1 CCY-3-O3 4.00% .sub. [1 kHz, 20 C.]: 5.3 CPY-2-O2 9.00% [1 kHz, 20 C.]: 2.1 CCH-301 5.00% K.sub.1 [pN, 20 C.]: 16.7 CC-3-V1 8.00% K.sub.3 [pN, 20 C.]: 18.3 CC-5-V 13.00% V.sub.0 [pN, 20 C.]: 3.11 CCP-V-1 13.00% .sub.1 [mPa .Math. s, 20 C.]: 133 CCP-V2-1 13.00% CH-33 3.00% CH-35 3.00% CP-43 3.00% CCPC-33 2.00%

(88) H22: Nematic Host-Mixture

(89) TABLE-US-00027 CY-3-O2 8.00% Clearing point [ C.]: 102 CY-3-O4 4.00% n [589 nm, 20 C.]: 0.1501 CY-5-O2 12.00% .sub. [1 kHz, 20 C.]: 4.1 CY-5-O4 6.00% .sub. [1 kHz, 20 C.]: 10.2 CCY-3-O2 6.00% [1 kHz, 20 C.]: 6.1 CCY-4-O2 6.00% K.sub.1 [pN, 20 C.]: 15.9 CCY-5-O2 6.00% K.sub.3 [pN, 20 C.]: 18.3 CCY-3-O3 6.00% V.sub.0 [pN, 20 C.]: 1.83 CPY-2-O2 12.00% .sub.1 [mPa .Math. s, 20 C.]: 404 CPY-3-O2 12.00% PYP-2-3 10.00% PYP-2-4 10.00% CPTP-301 2.00%

(90) H23: Nematic Host-Mixture

(91) TABLE-US-00028 CY-3-O2 2.00% Clearing point [ C.]: 100 CY-3-O4 6.00% n [589 nm, 20 C.]: 0.1508 CY-5-O4 2.00% .sub. [1 kHz, 20 C.]: 3.3 CCY-3-O2 1.50% .sub. [1 kHz, 20 C.]: 5.3 CPY-2-O2 9.00% [1 kHz, 20 C.]: 1.9 CPY-3-O2 9.00% K.sub.1 [pN, 20 C.]: 15.7 PYP-2-3 10.00% K.sub.3 [pN, 20 C.]: 16.4 PYP-2-4 10.00% V.sub.0 [pN, 20 C.]: 3.06 PTP-102 1.50% .sub.1 [mPa .Math. s, 20 C.]: 122 CPTP-301 5.00% CPTP-302 4.00% PCH-301 5.50% CC-4-V 14.00% CC-5-V 8.00% CCP-V-1 7.50% BCH-32 5.00%

(92) H24: Nematic Host-Mixture

(93) TABLE-US-00029 CY-3-O2 17.00% Clearing point [ C.]: 101 CY-3-O4 20.00% n [589 nm, 20 C.]: 0.0969 CY-5-O2 5.50% .sub. [1 kHz, 20 C.]: 4.0 CCY-3-O2 6.50% .sub. [1 kHz, 20 C.]: 10.0 CCY-3-O3 6.50% [1 kHz, 20 C.]: 6.0 CCY-4-O2 6.50% K.sub.1 [pN, 20 C.]: 14.5 CCY-5-O2 6.50% K.sub.3 [pN, 20 C.]: 17.3 CPY-2-O2 10.50% V.sub.0 [pN, 20 C.]: 1.80 CCH-34 3.00% .sub.1 [mPa .Math. s, 20 C.]: 322 CH-33 3.00% CH-35 3.00% CH-43 3.00% CCPC-33 3.00% CCPC-34 3.00% CCPC-35 3.00%

(94) H25: Nematic Host-Mixture

(95) TABLE-US-00030 CY-3-O2 2.40% Clearing point [ C.]: 101 CY-3-O4 18.80% n [589 nm, 20 C.]: 0.0970 CY-5-O2 2.40% .sub. [1 kHz, 20 C.]: 3.7 CCY-3-O2 7.00% .sub. [1 kHz, 20 C.]: 8.2 CCY-5-O2 7.90% [1 kHz, 20 C.]: 4.5 CCY-2-1 4.90% K.sub.1 [pN, 20 C.]: 14.8 CCY-3-1 5.30% K.sub.3 [pN, 20 C.]: 17.6 CPY-2-O2 5.70% V.sub.0 [pN, 20 C.]: 2.09 CCH-301 8.50% .sub.1 [mPa .Math. s, 20 C.]: 244 CH-33 0.90% CH-35 0.90% CP-33 1.20% CP-35 1.20% CCPC-33 3.00% CCPC-34 2.70% CCPC-35 0.60% CCY-3-O3 4.90% CCY-4-O2 4.90% CPY-3-O2 4.20% PYP-2-3 3.50% CCH-303 4.20% CCH-501 4.90%

(96) H26: Nematic Host-Mixture

(97) TABLE-US-00031 CY-3-O2 17.00% Clearing point [ C.]: 101 CY-3-O4 20.00% n [589 nm, 20 C.]: 0.0969 CY-5-O2 5.50% .sub. [1 kHz, 20 C.]: 4.0 CCY-3-O2 6.50% .sub. [1 kHz, 20 C.]: 10.0 CCY-3-O3 6.50% [1 kHz, 20 C.]: 6.0 CCY-4-O2 6.50% K.sub.1 [pN, 20 C.]: 14.5 CCY-5-O2 6.50% K.sub.3 [pN, 20 C.]: 17.3 CPY-2-O2 10.50% V.sub.0 [pN, 20 C.]: 1.80 CCH-34 3.00% .sub.1 [mPa .Math. s, 20 C.]: 322 CH-33 3.00% CH-35 3.00% CH-43 3.00% CCPC-33 3.00% CCPC-34 3.00% CCPC-35 3.00%

(98) H27: Nematic Host-Mixture

(99) TABLE-US-00032 CY-3-O2 16.00% Clearing point [ C.]: 101 CY-3-O4 20.00% n [589 nm, 20 C.]: 0.0953 CCY-3-O2 5.00% .sub. [1 kHz, 20 C.]: 3.9 CCY-3-O3 5.00% .sub. [1 kHz, 20 C.]: 9.4 CCY-4-O2 5.00% [1 kHz, 20 C.]: 5.5 CCY-5-O2 5.00% K.sub.1 [pN, 20 C.]: 16.2 CLY-2-O4 5.00% K.sub.3 [pN, 20 C.]: 17.2 CLY-3-O2 5.00% V.sub.0 [pN, 20 C.]: 1.85 CLY-3-O3 5.00% .sub.1 [mPa .Math. s, 20 C.]: 276 CPY-2-O2 5.00% CC-5-V 9.00% CH-33 3.00% CH-35 3.00% CP-33 3.00% CCPC-33 3.00% CCPC-34 3.00%

(100) H28: Nematic Host-Mixture

(101) TABLE-US-00033 CY-3-O2 8.00% Clearing point [ C.]: 100 CY-3-O4 15.00% n [589 nm, 20 C.]: 0.0948 CY-5-O2 8.00% .sub. [1 kHz, 20 C.]: 3.9 CY-5-O4 10.00% .sub. [1 kHz, 20 C.]: 9.2 CCY-3-O2 6.00% [1 kHz, 20 C.]: 5.3 CCY-3-O3 6.00% K.sub.1 [pN, 20 C.]: 14.6 CCY-4-O2 6.00% K.sub.3 [pN, 20 C.]: 17.3 CCY-5-O2 6.00% V.sub.0 [pN, 20 C.]: 1.90 CPY-2-O2 10.00% .sub.1 [mPa .Math. s, 20 C.]: 298 CC-5-V 7.00% CH-33 3.00% CH-35 3.00% CP-33 3.00% CCPC-33 3.00% CCPC-34 3.00% CCPC-35 3.00%

(102) H29: Nematic Host-Mixture

(103) TABLE-US-00034 CY-3-O2 9.00% Clearing point [ C.]: 106 CY-3-O4 9.00% n [589 nm, 20 C.]: 0.1077 CY-5-O2 12.00% .sub. [1 kHz, 20 C.]: 3.9 CY-5-O4 11.00% .sub. [1 kHz, 20 C.]: 9.5 CCY-3-O2 6.00% [1 kHz, 20 C.]: 5.6 CCY-3-O3 6.00% K.sub.1 [pN, 20 C.]: 15.8 CCY-4-O2 6.00% K.sub.3 [pN, 20 C.]: 19.4 CCY-5-O2 6.00% V.sub.0 [pN, 20 C.]: 1.96 CPY-2-O2 8.00% .sub.1 [mPa .Math. s, 20 C.]: 341 CPY-3-O2 7.00% CCP-V-1 11.00% CCPC-33 3.00% CCPC-34 3.00% CCPC-35 3.00%

(104) H30: Nematic Host-Mixture

(105) TABLE-US-00035 CY-3-O2 8.00% Clearing point [ C.]: 98 CY-3-O4 17.00% n [589 nm, 20 C.]: 0.0914 CY-5-O2 8.00% .sub. [1 kHz, 20 C.]: 3.8 CCY-3-O2 8.00% .sub. [1 kHz, 20 C.]: 8.9 CCY-3-O3 8.00% [1 kHz, 20 C.]: 5.1 CCY-4-O2 8.00% K.sub.1 [pN, 20 C.]: 15.5 CCY-5-O2 8.00% K.sub.3 [pN, 20 C.]: 16.8 CPY-2-O2 8.00% V.sub.0 [pN, 20 C.]: 1.92 CCH-301 3.00% .sub.1 [mPa .Math. s, 20 C.]: 256 CC-5-V 10.00% CH-33 3.00% CH-35 3.00% CP-33 3.00% CP-35 2.00% CCPC-33 3.00%

(106) H31: Nematic Host-Mixture

(107) TABLE-US-00036 CY-3-O2 7.00% Clearing point [ C.]: 105 CY-3-O4 16.00% n [589 nm, 20 C.]: 0.1024 CCY-3-O2 6.00% .sub. [1 kHz, 20 C.]: 3.4 CCY-3-O3 6.00% .sub. [1 kHz, 20 C.]: 6.6 CCY-4-O2 6.00% [1 kHz, 20 C.]: 3.2 CPY-2-O2 7.50% K.sub.1 [pN, 20 C.]: 18.4 CPY-3-O2 7.50% K.sub.3 [pN, 20 C.]: 21.2 CC-3-V1 8.00% V.sub.0 [pN, 20 C.]: 2.79 CC-5-V 9.00% .sub.1 [mPa .Math. s, 20 C.]: 171 CCP-V-1 13.50% CCP-V2-1 13.50%

(108) H32: Nematic Host-Mixture

(109) TABLE-US-00037 CY-3-O2 9.00% Clearing point [ C.]: 106 CY-3-O4 9.00% n [589 nm, 20 C.]: 0.1077 CY-5-O2 12.00% .sub. [1 kHz, 20 C.]: 3.9 CY-5-O4 11.00% .sub. [1 kHz, 20 C.]: 9.5 CCY-3-O2 6.00% [1 kHz, 20 C.]: 5.6 CCY-3-O3 6.00% K.sub.1 [pN, 20 C.]: 15.8 CCY-4-O2 6.00% K.sub.3 [pN, 20 C.]: 19.4 CCY-5-O2 6.00% V.sub.0 [pN, 20 C.]: 1.96 CPY-2-O2 8.00% .sub.1 [mPa .Math. s, 20 C.]: 341 CPY-3-O2 7.00% CCP-V-1 11.00% CCPC-33 3.00% CCPC-34 3.00% CCPC-35 3.00%

(110) H33: Nematic Host-Mixture

(111) TABLE-US-00038 CY-3-O2 4.00% Clearing point [ C.]: 100 CY-3-O4 12.50% n [589 nm, 20 C.]: 0.1566 CCY-3-O2 3.50% .sub. [1 kHz, 20 C.]: 3.6 CPY-2-O2 12.00% .sub. [1 kHz, 20 C.]: 6.6 CPY-3-O2 12.00% [1 kHz, 20 C.]: 3.0 PYP-2-3 11.00% K.sub.1 [pN, 20 C.]: 15.5 PYP-2-4 11.00% K.sub.3 [pN, 20 C.]: 17.1 CPTP-301 5.00% V.sub.0 [pN, 20 C.]: 2.50 CPTP-302 5.00% .sub.1 [mPa .Math. s, 20 C.]: 202 CC-4-V 14.00% CC-5-V 7.00% BCH-32 3.00%

(112) H34: Nematic Host-Mixture

(113) TABLE-US-00039 CY-3-O2 8.00% Clearing point [ C.]: 98 CY-3-O4 17.00% n [589 nm, 20 C.]: 0.0914 CY-5-O2 8.00% .sub. [1 kHz, 20 C.]: 3.8 CCY-3-O2 8.00% .sub. [1 kHz, 20 C.]: 8.9 CCY-3-O3 8.00% [1 kHz, 20 C.]: 5.1 CCY-4-O2 8.00% K.sub.1 [pN, 20 C.]: 15.5 CCY-5-O2 8.00% K.sub.3 [pN, 20 C.]: 16.8 CPY-2-O2 8.00% V.sub.0 [pN, 20 C.]: 1.92 CCH-301 3.00% .sub.1 [mPa .Math. s, 20 C.]: 256 CC-5-V 10.00% CH-33 3.00% CH-35 3.00% CP-33 3.00% CP-35 2.00% CCPC-33 3.00%

(114) H35: Nematic Host-Mixture

(115) TABLE-US-00040 CY-3-O2 2.40% Clearing point [ C.]: 101 CY-3-O4 18.80% n [589 nm, 20 C.]: 0.0970 CY-5-O2 2.40% .sub. [1 kHz, 20 C.]: 3.7 CCY-3-O2 7.00% .sub. [1 kHz, 20 C.]: 8.2 CCY-5-O2 7.90% [1 kHz, 20 C.]: 4.5 CCY-2-1 4.90% K.sub.1 [pN, 20 C.]: 14.8 CCY-3-1 5.30% K.sub.3 [pN, 20 C.]: 17.6 CPY-2-O2 5.70% V.sub.0 [pN, 20 C.]: 2.09 CCH-301 8.50% .sub.1 [mPa .Math. s, 20 C.]: 244 CH-33 0.90% CH-35 0.90% CP-33 1.20% CP-35 1.20% CCPC-33 3.00% CCPC-34 2.70% CCPC-35 0.60% CCY-3-O3 4.90% CCY-4-O2 4.90% CPY-3-O2 4.20% PYP-2-3 3.50% CCH-303 4.20% CCH-501 4.90%

(116) H36: Nematic Host-Mixture

(117) TABLE-US-00041 CY-3-O2 6.00% Clearing point [ C.]: 101 CY-3-O4 13.00% n [589 nm, 20 C.]: 0.1483 CCY-3-O2 6.00% .sub. [1 kHz, 20 C.]: 3.6 CCY-3-O3 5.00% .sub. [1 kHz, 20 C.]: 7.0 CPY-2-O2 4.00% [1 kHz, 20 C.]: 3.4 CC-4-V 14.00% K.sub.1 [pN, 20 C.]: 16.6 CCP-V-1 10.00% K.sub.3 [pN, 20 C.]: 18.8 CCP-V2-1 11.00% V.sub.0 [pN, 20 C.]: 2.47 CPTP-3-1 5.00% .sub.1 [mPa .Math. s, 20 C.]: PTP-3O2FF 8.00% PTP-5O2FF 8.00% CPTP-3O2FF 5.00% CPTP-5O2FF 5.00%

(118) H37: Nematic Host-Mixture

(119) TABLE-US-00042 CY-3-O2 10.00% Clearing point [ C.]: 100 CY-3-O4 20.00% n [589 nm, 20 C.]: 0.0865 CY-5-O4 20.00% .sub. [1 kHz, 20 C.]: 3.9 CCY-3-O2 6.00% .sub. [1 kHz, 20 C.]: 9.3 CCY-3-O3 6.00% [1 kHz, 20 C.]: 5.4 CCY-4-O2 6.00% K.sub.1 [pN, 20 C.]: 15.6 CCY-5-O2 6.00% K.sub.3 [pN, 20 C.]: 16.6 CH-33 3.00% V.sub.0 [pN, 20 C.]: 1.84 CH-35 3.50% .sub.1 [mPa .Math. s, 20 C.]: 347 CH-43 3.50% CH-45 3.50% CCPC-33 4.00% CCPC-34 4.50% CCPC-35 4.00%

(120) H38: Nematic Host-Mixture

(121) TABLE-US-00043 CY-3-O2 3.00% Clearing point [ C.]: 102 CY-3-O4 10.00% n [589 nm, 20 C.]: 0.1602 CCY-3-O2 6.00% .sub. [1 kHz, 20 C.]: 3.8 CCY-3-O3 6.00% .sub. [1 kHz, 20 C.]: 7.8 CCY-4-O2 6.00% [1 kHz, 20 C.]: 4.0 CPY-2-O2 5.00% K.sub.1 [pN, 20 C.]: 16.8 CC-4-V 14.00% K.sub.3 [pN, 20 C.]: 19.3 CCP-V-1 5.00% V.sub.0 [pN, 20 C.]: 2.32 CCP-V2-1 10.00% .sub.1 [mPa .Math. s, 20 C.]: 216 PPTUI-3-2 3.00% PTP-3O2FF 11.00% PTP-5O2FF 11.00% CPTP-3O2FF 5.00% CPTP-5O2FF 5.00%

(122) H39: Nematic Host-Mixture

(123) TABLE-US-00044 CY-3-O2 5.00% Clearing point [ C.]: 102 CY-3-O4 15.00% n [589 nm, 20 C.]: 0.2503 CCY-3-O2 6.00% .sub. [1 kHz, 20 C.]: 4.3 CCY-3-O3 6.00% .sub. [1 kHz, 20 C.]: 8.3 CPY-2-O2 3.00% [1 kHz, 20 C.]: 4.0 PTP-102 5.00% K.sub.1 [pN, 20 C.]: 19.5 PPTUI-3-2 15.00% K.sub.3 [pN, 20 C.]: 24.0 PPTUI-3-4 11.00% V.sub.0 [pN, 20 C.]: 2.57 PTP-3O2FF 12.00% .sub.1 [mPa .Math. s, 20 C.]: 392 PTP-5O2FF 12.00% CPTP-3O2FF 5.00% CPTP-5O2FF 5.00%

(124) H40: Nematic Host-Mixture

(125) TABLE-US-00045 CY-3-O4 12.00% Clearing point [ C.]: 91 PY-3-O2 6.50% n [589 nm, 20 C.]: 0.2100 CCY-3-O2 2.00% .sub. [1 kHz, 20 C.]: 4.0 CPY-2-O2 3.50% .sub. [1 kHz, 20 C.]: 7.1 CC-4-V 13.50% [1 kHz, 20 C.]: 3.1 CC-5-V 4.00% K.sub.1 [pN, 20 C.]: 15.3 PPTUI-3-2 15.00% K.sub.3 [pN, 20 C.]: 19.3 PPTUI-3-4 5.50% V.sub.0 [pN,20 C.]: 2.64 PTP-3O2FF 12.00% .sub.1 [mPa .Math. s, 20 C.]: 211 PTP-5O2FF 12.00% CPTP-3O2FF 5.00% CPTP-5O2FF 5.00% CCPC-33 4.00%

(126) H41: Nematic Host-Mixture

(127) TABLE-US-00046 D-302FF 8.00% Clearing point [ C.]: 102 D-402FF 8.00% n [589 nm, 20 C.]: 0.14780 D-502FF 8.00% .sub. [1 kHz, 20 C.]: 3.4 PCH-301 18.00% .sub. [1 kHz, 20 C.]: 5.1 PCH-302 15.00% [1 kHz, 20 C.]: 1.7 PCH-304 4.00% PTP-102 4.00% PTP-201 4.00% CPTP-301 6.00% CPTP-302 6.00% CPTP-303 7.00% CCPC-33 4.00% CCPC-34 4.00% CCPC-35 4.00%

(128) H42: Nematic Host-Mixture

(129) TABLE-US-00047 D-302FF 15.00% Clearing point [ C.]: 109 D-402FF 15.00% n [589 nm, 20 C.]: 0.1727 D-502FF 15.00% .sub. [1 kHz, 20 C.]: 5.2 CP-302FF 5.00% .sub. [1 kHz, 20 C.]: 13.2 CP-402FF 5.00% [1 kHz, 20 C.]: 8.0 CP-502FF 5.00% K.sub.1 [pN, 20 C.]: 15.6 PTP-3O2FF 10.00% K.sub.3 [pN, 20 C.]: 22.8 PTP-5O2FF 10.00% CPTP-3O2FF 10.00% CPTP-5O2FF 10.00%

(130) H43: Nematic Host-Mixture

(131) TABLE-US-00048 D-302FF 7.00% Clearing point [ C.]: 85 D-402FF 7.00% n [589 nm, 20 C.]: 0.1640 D-502FF 7.00% .sub. [1 kHz, 20 C.]: 3.7 PTP-3O2FF 10.00% .sub. [1 kHz, 20 C.]: 6.4 PTP-5O2FF 10.00% [1 kHz, 20 C.]: 2.7 CPTP-301 5.00% CPTP-302 5.00% CPTP-303 5.00% PCH-301 19.00% PCH-302 17.00% CBC-33F 5.00% CBC-53F 3.00%

(132) H44: Nematic Host-Mixture

(133) TABLE-US-00049 CCPC-33 1.50% Clearing point [ C.]: 91 CCPC-34 1.50% n [589 nm, 20 C.]: 0.1029 CCPC-35 1.50% .sub. [1 kHz, 20 C.]: 3.5 CCY-2-1 4.50% .sub. [1 kHz, 20 C.]: 7.2 CCY-3-1 3.50% [1 kHz, 20 C.]: 3.7 CCY-3-O2 7.00% K.sub.1 [pN, 20 C.]: 15.5 CCY-3-O3 8.00% K.sub.3 [pN, 20 C.]: 15.2 CCY-4-O2 7.00% V.sub.0 [pN, 20 C.]: 2.21 CPY-2-O2 6.00% .sub.1 [mPa .Math. s, 20 C.]: 231 CPY-3-O2 6.00% CY-3-O4 12.00% CY-5-O4 12.00% PCH-53 10.50% CCH-34 5.50% CCOC-3-3 2.00% CCOC-4-3 2.00% CCOC-3-5 2.00% CBC-33 1.50% PP-1-2V1 6.00%

(134) H45: Nematic Host-Mixture

(135) TABLE-US-00050 CY-5-O2 7.00% Clearing point [ C.]: 95 CPY-2-O2 11.00% n [589 nm, 20 C.]: 0.1268 CPY-3-O2 10.00% .sub. [1 kHz, 20 C.]: 4.0 PYP-2-3 6.00% .sub. [1 kHz, 20 C.]: 7.7 PYP-2-4 7.00% [1 kHz, 20 C.]: 3.7 CC-4-V 17.00% K.sub.1 [pN, 20 C.]: 15.5 CC-3-V1 9.00% K.sub.3 [pN, 20 C.]: 15.2.0 CCH-34 5.00% V.sub.0 [pN, 20 C.]: 2.15 CPYP-3-2 5.00% .sub.1 [mPa .Math. s, 20 C.]: 155 CPYP-2-1 5.00% CK-3-F 9.00% CK-5-F 9.00%

(136) H46: Nematic Host-Mixture

(137) TABLE-US-00051 CY-3-O4 18.00% Clearing point [ C.]: 96 CY-5-O2 10.00% n [589 nm, 20 C.]: 0.1275 CCY-4-O2 10.00% .sub. [1 kHz, 20 C.]: 4.0 CCY-3-O3 10.00% .sub. [1 kHz, 20 C.]: 9.1 CPY-2-O2 11.00% [1 kHz, 20 C.]: 5.1 CPY-3-O2 12.00% K.sub.1 [pN, 20 C.]: 14.4 PYP-2-3 5.00% K.sub.3 [pN, 20 C.]: 15.6 PYP-2-4 4.00% V.sub.0 [pN, 20 C.]: 1.84 CC-4-V 13.00% .sub.1 [mPa .Math. s, 20 C.]: 253 CPYP-3-2 7.00%

Example M1

(138) The compound of the formula I-8a-3

(139) ##STR00384##

(140) (1.5%) is added to the nematic host mixture H1. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer). The LC-mixture shows a spontaneous homeotropic (vertical) orientation with respect to the surface of the substrates. The orientation is stable until the clearing point and the resulting VA-cell can be reversibly switched. Crossed polarizers are needed to display the switching.

(141) By using additives like the compound of the formula I-8a-3, no alignment layer (e.g. no PI coating) is required anymore for PM-VA, PVA, MVA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Example 1P a)

Polymer Stabilization of the LC Mixture of Example M1

(142) The polymerizable derivative RM-1 (0.3%) is added to the nematic LC-mixture of Example M1. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(143) The LC-mixture shows a spontaneous homeotropic (vertical) orientation, with respect to the surface of the substrates. The resulting VA-cell is treated with UV-light (15 min, 100 mW/cm.sup.2) after having applied to the cell a voltage higher than the optical threshold. The polymerizable derivative polymerizes and, as a consequence, the homeotropic self-orientation is stabilized and the tilt of the mixture is tuned. The resulting PSA-VA-cell can be reversibly switched even at high temperatures. The switching times are reduced, compared to the not polymerized system.

(144) Additives like Irganox 1076 (BASF) may be added (e.g. 0.001%) for preventing spontaneous polymerization. UV-cut filter may be used during polymerization for preventing damage of the mixtures (e.g. 340 nm cut-filter).

(145) By using additives like the compound of the formula I-8a-3 in combination with RM-1, no alignment layer is required anymore for PSA, PS-VA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Example 1P b)

Polymer Stabilization of the LC Mixture of Example M1

(146) The polymerizable derivative RM-41 (0.3%) is added to the nematic LC-mixture of Example M1. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer). The resulting cell is treated according to Example 1P a) and similar results are obtained.

(147) By using additives like the compound of the formula I-8a-3 in combination with RM-41, no alignment layer is required anymore for PSA, PS-VA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Examples M2 to M9 and 2P a) to 9P b)

(148) The compound of the formula I-8a-3 (1.5%) is added to the nematic host mixtures H2-H9. The resulting 8 mixtures are homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(149) The LC-mixtures show a spontaneous homeotropic (vertical) orientation with respect to the surface of the substrates. The orientation is stable until the clearing point and the resulting VA-cell can be reversibly switched. Crossed polarizers are needed to display the switching.

(150) The polymerizable derivative RM-1 (0.3%) or RM-41 (0.3%) is added to the nematic LC mixtures of Examples M2-M9. The resulting mixtures are homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer). The resulting cell is treated according to example 1P a). Equivalent results are obtained.

Examples 1P c) to 9P f)

(151) Analogues mixtures like 1P a) to 9P b) are obtained by mixing the nematic LC mixtures M1 to M9 with RM-37 (0.3%), RM-61 (0.3%), RM-80 (0.3%) or RM-84 (0.3%), obtaining mixtures 1P c) to 9P f). These mixtures are treated according to Example 1P a). In all cases an improvement of the switching times is found.

Example M10

(152) The compound of the formula I-1a-23

(153) ##STR00385##

(154) (1.5%) is added to the nematic host mixture H1. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(155) The LC-mixture shows a spontaneous homeotropic (vertical) orientation with respect to the surface of the substrates. The orientation is stable until the clearing point and the resulting VA-cell can be reversibly switched. Crossed polarizers are needed to display the switching.

(156) By using additives like the compound of the formula I-1a-23, no alignment layer (e.g. no PI coating) is required anymore for PM-VA, PVA, MVA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Example 10P a)

Polymer Stabilization of the LC Mixture of Example M10

(157) The polymerizable derivative RM-1 (0.3%) is added to the nematic LC-mixture of Example M10. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(158) The LC-mixture shows a spontaneous homeotropic (vertical) orientation, with respect to the surface of the substrates. The resulting VA-cell is treated with UV-light (15 min, 100 mW/cm.sup.2) after having applied to the cell a voltage higher than the optical threshold. The polymerizable derivative polymerizes and, as a consequence, the homeotropic self-orientation is stabilized and the tilt of the mixture is tuned. The resulting PSA-VA-cell can be reversibly switched even at high temperatures. The switching times are reduced, compared to the not polymerized system.

(159) Additives like Irganox 1076 (BASF) may be added (e.g. 0.001%) for preventing spontaneous polymerization. UV-cut filter may be used during polymerization for preventing damage of the mixtures (e.g. 340 nm cut-filter).

(160) By using additives like the compound of the formula I-1a-23 in combination with RM-1, no alignment layer is required anymore for PSA, PS-VA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Example 10P b)

Polymer Stabilization of the LC Mixture of Example M10

(161) The polymerizable derivative RM-41 (0.3%) is added to the nematic LC-mixture of Example M10. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer). The resulting cell is treated according to Example 2P a) and similar results are obtained.

(162) By using additives like the compound of the formula I-1a-23 in combination with RM-41, no alignment layer is required anymore for PSA, PS-VA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Examples M11 to M18 and 11P a) to 18P b)

(163) The compound of the formula I-1a-23 (1.5%) is added to the nematic host mixtures H2-H9. The resulting 8 mixtures are homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(164) The LC-mixtures show a spontaneous homeotropic (vertical) orientation with respect to the surface of the substrates. The orientation is stable until the clearing point and the resulting VA-cell can be reversibly switched. Crossed polarizers are needed to display the switching.

(165) The polymerizable derivative RM-1 (0.3%) or RM-41 (0.3%) is added to the nematic LC mixtures of Examples M11-M18. The resulting mixtures are homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer). The resulting cell is treated according to example 1P a). Equivalent results are obtained.

Examples 10P c) to 18P f)

(166) Analogues mixtures like 1P a) to 9P b) are obtained by mixing the nematic LC mixtures M11 to M18 with RM-37 (0.3%), RM-61 (0.3%), RM-80 (0.3%) or RM-84 (0.3%), obtaining mixtures 10P c) to 18P f). These mixtures are treated according to Example 1P a). In all cases an improvement of the switching times is found.

Example M19

(167) The compound of the formula I-4a-22

(168) ##STR00386##

(169) (1.5%) is added to the nematic host mixture H1. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(170) The LC-mixture shows a spontaneous homeotropic (vertical) orientation with respect to the surface of the substrates. The orientation is stable until the clearing point and the resulting VA-cell can be reversibly switched. Crossed polarizers are needed to display the switching.

(171) By using additives like the compound of the formula I-4a-22, no alignment layer (e.g. no PI coating) is required anymore for PM-VA, PVA, MVA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Example 19P a)

Polymer Stabilization of the LC Mixture of Example M19

(172) The polymerizable derivative RM-1 (0.3%) is added to the nematic LC-mixture of Example M19. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(173) The LC-mixture shows a spontaneous homeotropic (vertical) orientation, with respect to the surface of the substrates. The resulting VA-cell is treated with UV-light (15 min, 100 mW/cm.sup.2) after having applied to the cell a voltage higher than the optical threshold. The polymerizable derivative polymerizes and, as a consequence, the homeotropic self-orientation is stabilized and the tilt of the mixture is tuned. The resulting PSA-VA-cell can be reversibly switched even at high temperatures. The switching times are reduced, compared to the not polymerized system.

(174) Additives like Irganox 1076 (BASF) may be added (e.g. 0.001%) for preventing spontaneous polymerization. UV-cut filter may be used during polymerization for preventing damage of the mixtures (e.g. 340 nm cut-filter).

(175) By using additives like the compound of the formula I-4a-22 in combination with RM-1, no alignment layer is required anymore for PSA, PS-VA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Example 19P b)

Polymer Stabilization of the LC Mixture of Example M19

(176) The polymerizable derivative RM-41 (0.3%) is added to the nematic LC-mixture of Example M19. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer). The resulting cell is treated according to Example 1P a) and similar results are obtained.

(177) By using additives like the compound of the formula I-4a-22 in combination with RM-41, no alignment layer is required anymore for PSA, PS-VA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Examples M20 to M27 and 20P a) to 27P b)

(178) The compound of the formula I-4a-22 (1.5%) is added to the nematic host mixtures H2-H9. The resulting 8 mixtures are homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(179) The LC-mixtures show a spontaneous homeotropic (vertical) orientation with respect to the surface of the substrates. The orientation is stable until the clearing point and the resulting VA-cell can be reversibly switched. Crossed polarizers are needed to display the switching.

(180) The polymerizable derivative RM-1 (0.3%) or RM-41 (0.3%) is added to the nematic LC mixtures of Examples M20-M27. The resulting mixtures are homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer). Theresulting cell is treated according to example 1P a). Equivalent results are obtained.

Examples 19P c) to 27P f)

(181) Analogues mixtures like 1P a) to 9P b) are obtained by mixing the nematic LC mixtures M20 to M27 with RM-37 (0.3%), RM-61 (0.3%), RM-80 (0.3%) or RM-84 (0.3%), obtaining mixtures 19P c) to 27P f). These mixtures are treated according to Example 1P a). In all cases an improvement of the switching times is found.

Example M28

(182) The compound of the formula I-3a-22

(183) ##STR00387##

(184) (1.5%) is added to the nematic host mixture H1. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(185) The LC-mixture shows a spontaneous homeotropic (vertical) orientation with respect to the surface of the substrates. The orientation is stable until the clearing point and the resulting VA-cell can be reversibly switched. Crossed polarizers are needed to display the switching.

(186) By using additives like the compound of the formula I-3a-22, no alignment layer (e.g. no PI coating) is required anymore for PM-VA, PVA, MVA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Example 28P a)

Polymer Stabilization of the LC Mixture of Example M28

(187) The polymerizable derivative RM-1 (0.3%) is added to the nematic LC-mixture of Example M28. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(188) The LC-mixture shows a spontaneous homeotropic (vertical) orientation, with respect to the surface of the substrates. The resulting VA-cell is treated with UV-light (15 min, 100 mW/cm.sup.2) after having applied to the cell a voltage higher than the optical threshold. The polymerizable derivative polymerizes and, as a consequence, the homeotropic self-orientation is stabilized and the tilt of the mixture is tuned. The resulting PSA-VA-cell can be reversibly switched even at high temperatures. The switching times are reduced, compared to the not polymerized system.

(189) Additives like Irganox 1076 (BASF) may be added (e.g. 0.001%) for preventing spontaneous polymerization. UV-cut filter may be used during polymerization for preventing damage of the mixtures (e.g. 340 nm cut-filter).

(190) By using additives like the compound of the formula I-3a-22 in combination with RM-1, no alignment layer is required anymore for PSA, PS-VA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Example 28P b)

Polymer Stabilization of the LC Mixture of Example M28

(191) The polymerizable derivative RM-41 (0.3%) is added to the nematic LC-mixture of Example M28. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer). The resulting cell is treated according to Example 1P a) and similar results are obtained.

(192) By using additives like the compound of the formula I-3a-22 in combination with RM-41, no alignment layer is required anymore for PSA, PS-VA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Examples M29 to M36 and 29P a) to 36P b)

(193) The compound of the formula I-3a-22 (1.5%) is added to the nematic host mixtures H2-H9. The resulting 8 mixtures are homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(194) The LC-mixtures show a spontaneous homeotropic (vertical) orientation with respect to the surface of the substrates. The orientation is stable until the clearing point and the resulting VA-cell can be reversibly switched. Crossed polarizers are needed to display the switching.

(195) The polymerizable derivative RM-1 (0.3%) or RM-41 (0.3%) is added to the nematic LC mixtures of Examples M29-M36. The resulting mixtures are homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer). The resulting cell is treated according to example 1P a). Equivalent results are obtained.

Examples 28P c) to 36P f)

(196) Analogues mixtures like 1P a) to 9P b) are obtained by mixing the nematic LC mixtures M29 to M36 with RM-37 (0.3%), RM-61 (0.3%), RM-80 (0.3%) or RM-84 (0.3%), obtaining mixtures 28P c) to 36P f). These mixtures are treated according to Example 1P a). In all cases an improvement of the switching times is found.

Example M37

(197) The compound of the formula I-3a-23

(198) ##STR00388##

(199) (1.5%) is added to the nematic host mixture H1. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(200) The LC-mixture shows a spontaneous homeotropic (vertical) orientation with respect to the surface of the substrates. The orientation is stable until the clearing point and the resulting VA-cell can be reversibly switched. Crossed polarizers are needed to display the switching.

(201) By using additives like the compound of the formula I-3a-23, no alignment layer (e.g. no PI coating) is required anymore for PM-VA, PVA, MVA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Example 37P a)

Polymer Stabilization of the LC Mixture of Example M37

(202) The polymerizable derivative RM-1 (0.3%) is added to the nematic LC-mixture of Example M37. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(203) The LC-mixture shows a spontaneous homeotropic (vertical) orientation, with respect to the surface of the substrates. The resulting VA-cell is treated with UV-light (15 min, 100 mW/cm.sup.2) after having applied to the cell a voltage higher than the optical threshold. The polymerizable derivative polymerizes and, as a consequence, the homeotropic self-orientation is stabilized and the tilt of the mixture is tuned. The resulting PSA-VA-cell can be reversibly switched even at high temperatures. The switching times are reduced, compared to the not polymerized system.

(204) Additives like Irganox 1076 (BASF) may be added (e.g. 0.001%) for preventing spontaneous polymerization. UV-cut filter may be used during polymerization for preventing damage of the mixtures (e.g. 340 nm cut-filter).

(205) By using additives like the compound of the formula I-3a-23 in combination with RM-1, no alignment layer is required anymore for PSA, PS-VA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Example 37P b)

Polymer Stabilization of the LC Mixture of Example M37

(206) The polymerizable derivative RM-41 (0.3%) is added to the nematic LC-mixture of Example M37. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer). The resulting cell is treated according to Example 1P a) and similar results are obtained.

(207) By using additives like the compound of the formula I-3a-23 in combination with RM-41, no alignment layer is required anymore for PSA, PS-VA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Examples M38 to M45 and 38P a) to 45P b)

(208) The compound of the formula I-3a-23 (1.5%) is added to the nematic host mixtures H2-H9. The resulting 8 mixtures are homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(209) The LC-mixtures show a spontaneous homeotropic (vertical) orientation with respect to the surface of the substrates. The orientation is stable until the clearing point and the resulting VA-cell can be reversibly switched. Crossed polarizers are needed to display the switching.

(210) The polymerizable derivative RM-1 (0.3%) or RM-41 (0.3%) is added to the nematic LC mixtures of Examples M38-M45. The resulting mixtures are homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer). The resulting cell is treated according to example 1P a). Equivalent results are obtained.

Examples 37P c) to 45P f)

(211) Analogues mixtures like 1P a) to 9P b) are obtained by mixing the nematic LC mixtures M38 to M45 with RM-37 (0.3%), RM-61 (0.3%), RM-80 (0.3%) or RM-84 (0.3%), obtaining mixtures 37P c) to 45P f). These mixtures are treated according to Example 1P a). In all cases an improvement of the switching times is found.

Example M46

(212) The compound of the formula I-5a-22

(213) ##STR00389##

(214) (1.5%) is added to the nematic host mixture H1. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(215) The LC-mixture shows a spontaneous homeotropic (vertical) orientation with respect to the surface of the substrates. The orientation is stable until the clearing point and the resulting VA-cell can be reversibly switched. Crossed polarizers are needed to display the switching.

(216) By using additives like the compound of the formula I-5a-22, no alignment layer (e.g. no PI coating) is required anymore for PVA, MVA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Example 46P a)

Polymer Stabilization of the LC Mixture of Example M46

(217) The polymerizable derivative RM-1 (0.3%) is added to the nematic LC-mixture of Example M46. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(218) The LC-mixture shows a spontaneous homeotropic (vertical) orientation, with respect to the surface of the substrates. The resulting VA-cell is treated with UV-light (15 min, 100 mW/cm.sup.2) after having applied to the cell a voltage higher than the optical threshold. The polymerizable derivative polymerizes and, as a consequence, the homeotropic self-orientation is stabilized and the tilt of the mixture is tuned. The resulting PSA-VA-cell can be reversibly switched even at high temperatures. The switching times are reduced, compared to the not polymerized system.

(219) Additives like Irganox 1076 (BASF) may be added (e.g. 0.001%) for preventing spontaneous polymerization. UV-cut filter may be used during polymerization for preventing damage of the mixtures (e.g. 340 nm cut-filter).

(220) By using additives like the compound of the formula I-5a-22 in combination with RM-1, no alignment layer is required anymore for PSA, PS-VA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Example 46P b)

Polymer Stabilization of the LC Mixture of Example M46

(221) The polymerizable derivative RM-41 (0.3%) is added to the nematic LC-mixture of Example M46. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer). The resulting cell is treated according to Example 1P a) and similar results are obtained.

(222) By using additives like the compound of the formula I-5a-22 in combination with RM-41, no alignment layer is required anymore for PSA, PS-VA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Examples M47 to M54 and 47P a) to 54P b)

(223) The compound of the formula I-5a-22 (1.5%) is added to the nematic host mixtures H2-H9. The resulting 8 mixtures are homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(224) The LC-mixtures show a spontaneous homeotropic (vertical) orientation with respect to the surface of the substrates. The orientation is stable until the clearing point and the resulting VA-cell can be reversibly switched. Crossed polarizers are needed to display the switching.

(225) The polymerizable derivative RM-1 (0.3%) or RM-41 (0.3%) is added to the nematic LC mixtures of Examples M47-M54. The resulting mixtures are homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer). The resulting cell is treated according to example 1P a). Equivalent results are obtained.

Examples 46P c) to 54P f)

(226) Analogues mixtures like 1P a) to 9P b) are obtained by mixing the nematic LC mixtures M46 to M54 with RM-37 (0.3%), RM-61 (0.3%), RM-80 (0.3%) or RM-84 (0.3%), obtaining mixtures 46P c) to 54P f). These mixtures are treated according to Example 1P a). In all cases an improvement of the switching times is found.

Example M55

(227) The compound of the formula I-9a-3

(228) ##STR00390##

(229) (1.5%) is added to the nematic host mixture H1. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(230) The LC-mixture shows a spontaneous homeotropic (vertical) orientation with respect to the surface of the substrates. The orientation is stable until the clearing point and the resulting VA-cell can be reversibly switched. Crossed polarizers are needed to display the switching.

(231) By using additives like the compound of the formula I-9a-3, no alignment layer (e.g. no PI coating) is required anymore for PM-VA, PVA, MVA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Example 55P a)

Polymer Stabilization of the LC Mixture of Example M55

(232) The polymerizable derivative RM-1 (0.3%) is added to the nematic LC-mixture of Example M55. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(233) The LC-mixture shows a spontaneous homeotropic (vertical) orientation, with respect to the surface of the substrates. The resulting VA-cell is treated with UV-light (15 min, 100 mW/cm.sup.2) after having applied to the cell a voltage higher than the optical threshold. The polymerizable derivative polymerizes and, as a consequence, the homeotropic self-orientation is stabilized and the tilt of the mixture is tuned. The resulting PSA-VA-cell can be reversibly switched even at high temperatures. The switching times are reduced, compared to the not polymerized system.

(234) Additives like Irganox 1076 (BASF) may be added (e.g. 0.001%) for preventing spontaneous polymerization. UV-cut filter may be used during polymerization for preventing damage of the mixtures (e.g. 340 nm cut-filter).

(235) By using additives like the compound of the formula I-9a-3 in combination with RM-1, no alignment layer is required anymore for PSA, PS-VA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Example 55P b)

Polymer Stabilization of the LC Mixture of Example M55

(236) The polymerizable derivative RM-41 (0.3%) is added to the nematic LC-mixture of Example M55. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer). The resulting cell is treated according to Example 1P a) and similar results are obtained.

(237) By using additives like the compound of the formula I-9a-3 in combination with RM-41, no alignment layer is required anymore for PSA, PS-VA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Examples M56 to M63 and 56P a) to 63P b)

(238) The compound of the formula I-9a-3 (1.5%) is added to the nematic host mixtures H2-H9. The resulting 8 mixtures are homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(239) The LC-mixtures show a spontaneous homeotropic (vertical) orientation with respect to the surface of the substrates. The orientation is stable until the clearing point and the resulting VA-cell can be reversibly switched. Crossed polarizers are needed to display the switching.

(240) The polymerizable derivative RM-1 (0.3%) or RM-41 (0.3%) is added to the nematic LC mixtures of Examples M56-M63. The resulting mixtures are homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer). The resulting cell is treated according to example 1P a). Equivalent results are obtained.

Examples 55P c) to 63P f)

(241) Analogues mixtures like 1P a) to 9P b) are obtained by mixing the nematic LC mixtures M55 to M63 with RM-37 (0.3%), RM-61 (0.3%), RM-80 (0.3%) or RM-84 (0.3%), obtaining mixtures 55P c) to 63P f). These mixtures are treated according to Example 1P a). In all cases an improvement of the switching times is found.

(242) The voltage holding ratio (VHR) of the mixtures M1, M10, M19, M28, M37, M46 and M55 are reported in the table below:

(243) TABLE-US-00052 VHR after SA-Additive wt. % Initial VHR 120 C., 2 h Host H1 93.8 95.1 I-8a-3 2.0 87.3 92.4 I-1a-23 2.0 93.8 95.4 I-4a-22 2.0 88.0 91.9 I-3a-22 2.0 85.1 89.1 I-5a-22 2.0 76.6 79.9 I-9a-3 2.0 81.4 82.9 I-3a-23 2.0 87.8 89.1

Example M64

(244) 1.5% of the compound of the formula I-1a-23

(245) ##STR00391##

(246) and

(247) 0.05% of the compound of the formula

(248) ##STR00392##

(249) are added to the nematic host mixture H7. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer). The LC-mixture shows a spontaneous homeotropic (vertical) orientation with respect to the surface of the substrates. The orientation is stable until the clearing point and the resulting VA-cell can be reversibly switched. Crossed polarizers are needed to display the switching.

(250) By using additives like the compound of the formula I-1a-23, no alignment layer (e.g. no PI coating) is required anymore for PM-VA, PVA, MVA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Example 64P a)

Polymer Stabilization of the LC Mixture of Example M64

(251) The polymerizable derivative RM-1 (0.2%) is added to the nematic LC-mixture of Example M64. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(252) The LC-mixture shows a spontaneous homeotropic (vertical) orientation, with respect to the surface of the substrates. The resulting VA-cell is treated with UV-light (15 min, 100 mW/cm.sup.2) after having applied to the cell a voltage higher than the optical threshold. The polymerizable derivative polymerizes and, as a consequence, the homeotropic self-orientation is stabilized and the tilt of the mixture is tuned. The resulting PSA-VA-cell can be reversibly switched even at high temperatures. The switching times are reduced, compared to the not polymerized system. Additives like Irganox 1076 (BASF) may be added (e.g. 0.001%) for preventing spontaneous polymerization. UV-cut filter may be used during polymerization for preventing damage of the mixtures (e.g. 340 nm cut-filter).

(253) By using additives like the compound of the formula I-1a-23 in combination with RM-1, no alignment layer is required anymore for PSA, PS-VA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Examples M65 to M111 and 65P a) to 111P b)

(254) The compound of the formula I-3a-23 (1.5%) is added to the nematic host mixtures H10-H46. The resulting 8 mixtures are homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(255) The LC-mixtures show a spontaneous homeotropic (vertical) orientation with respect to the surface of the substrates. The orientation is stable until the clearing point and the resulting VA-cell can be reversibly switched. Crossed polarizers are needed to display the switching. The polymerizable derivative RM-1 (0.3%) or RM-41 (0.3%) is added to the nematic LC mixtures of Examples M65-M111. The resulting mixtures are homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer). The resulting cell is treated according to example 1P a). Equivalent results are obtained.

Examples 65P c) to 111P f)

(256) Analogues mixtures like 1P a) to 9P b) are obtained by mixing the nematic LC mixtures M38 to M45 with RM-37 (0.3%), RM-61 (0.3%), RM-80 (0.3%) or RM-84 (0.3%), obtaining mixtures 37P c) to 45P f). These mixtures are treated according to Example 1P a). In all cases an improvement of the switching times is found.

Example M112

(257) The compound of the formula I-5a-22

(258) ##STR00393##

(259) (1.5%) is added to the nematic host mixture H46. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(260) The LC-mixture shows a spontaneous homeotropic (vertical) orientation with respect to the surface of the substrates. The orientation is stable until the clearing point and the resulting VA-cell can be reversibly switched. Crossed polarizers are needed to display the switching.

(261) By using additives like the compound of the formula I-5a-22, no alignment layer (e.g. no PI coating) is required anymore for PVA, MVA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Example 112P a)

Polymer Stabilization of the LC Mixture of Example M112

(262) The polymerizable derivative RM-1 (0.3%) is added to the nematic LC-mixture of Example M112. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer).

(263) The LC-mixture shows a spontaneous homeotropic (vertical) orientation, with respect to the surface of the substrates. The resulting VA-cell is treated with UV-light (15 min, 100 mW/cm.sup.2) after having applied to the cell a voltage higher than the optical threshold. The polymerizable derivative polymerizes and, as a consequence, the homeotropic self-orientation is stabilized and the tilt of the mixture is tuned. The resulting PSA-VA-cell can be reversibly switched even at high temperatures. The switching times are reduced, compared to the not polymerized system.

(264) Additives like Irganox 1076 (BASF) may be added (e.g. 0.001%) for preventing spontaneous polymerization. UV-cut filter may be used during polymerization for preventing damage of the mixtures (e.g. 340 nm cut-filter).

(265) By using additives like the compound of the formula I-5a-22 in combination with RM-1, no alignment layer is required anymore for PSA, PS-VA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

Example 112P b)

Polymer Stabilization of the LC Mixture of Example M112

(266) The polymerizable derivative RM-41 (0.3%) is added to the nematic LC-mixture of Example M112. The resulting mixture is homogenised and filled into an alignment-free test cell (cell thickness d4.0 m, ITO coating on both sides (structured ITO in case of a multi-domain switching), no alignment layer and no passivation layer). The resulting cell is treated according to Example 1P a) and similar results are obtained.

(267) By using additives like the compound of the formula I-5a-22 in combination with RM-41, no alignment layer is required anymore for PSA, PS-VA, and other analogue display technologies based on the combination <0 and homeotropic orientation.

(268) 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.

(269) 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.

(270) 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.

(271) The entire disclosures of all applications, patents and publications, cited herein and of corresponding European Application No. 13005833.2, filed Dec. 16, 2013 are incorporated by reference herein.