Polymerisable compounds and the use thereof in liquid-crystal displays

Abstract

The present invention relates to polymerizable compounds, to processes and intermediates for the preparation thereof, to liquid-crystal (LC) media comprising them, and to the use of the polymerizable compounds and LC media for optical, electro-optical and electronic purposes, in particular in LC displays, especially in LC displays of the polymer sustained alignment type.

Claims

1. A compound of formula I ##STR00331## in which A.sup.1, A.sup.2 denote, independently of each other, aryl or heteroaryl having 4 to 30 ring atoms, which is mono- or polycyclic and is optionally substituted, R.sup.a, R.sup.b denote, independently of each other, P-Sp-, H, F, Cl, CN, or straight chain, branched or cyclic alkyl having 1 to 25 C atoms, wherein one or more non-adjacent CH.sub.2-groups are optionally replaced by O, S, CO, COO, OCO, or OCOO in such a manner that O- and/or S-atoms are not directly connected with each other, and wherein one or more H atoms are each optionally replaced by F, Cl or P-Sp-, Sp denotes, on each occurrence identically or differently, a spacer group or a single bond, P denotes, on each occurrence identically or differently, a polymerisable group selected from the group consisting of CH.sub.2CW.sup.1COO, CH.sub.2CHO, (CH.sub.2CH).sub.2CHOCO, (CH.sub.2CH).sub.2CHO, ##STR00332## W.sup.1 denotes H, F, Cl or CH.sub.3, W.sup.2 denotes H or alkyl having 1 to 5 C atoms, k.sub.1 denotes 0 or 1, and a, b denote, independently of each other, 0, 1 or 2, wherein all the benzene groups in the compound of formula I are optionally substituted by one or two groups L, wherein L denotes P, P-Sp-, F, Cl, 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 or heteroaryl having 5 to 20 ring atoms, or straight-chain or branched alkyl having 1 to 25 C atoms, in which one or more non-adjacent CH.sub.2 groups are optionally each replaced, independently of one another, b 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 one or more H atoms are optionally replaced by F, Cl, CN, P or P-Sp-, R.sup.x denotes H, F, Cl, CN, or a straight chain, branched or cyclic alkyl having 1 to 25 C atoms, wherein one or more non-adjacent CH.sub.2-groups are optionally replaced by O, S, CO, COO, OCO, or OCOO in such a manner that O- and/or S-atoms are not directly connected with each other, and wherein one or more H atoms are each optionally replaced by F, Cl, P or P-Sp-, R.sup.0 and R.sup.00 each, independently of one another, denote H or alkyl having 1 to 20 C atoms, and Y.sup.1 is halogen, which compound of formula I contains exactly three polymerizable groups.

2. The compound of claim 1, wherein A.sup.1 and A.sup.2 are each independently benzene or naphthalene, wherein each benzene is independently optionally substituted by one or two groups L, and each naphthalene is independently optionally substituted by one or more groups L, wherein L denotes P, P-Sp-, F, Cl, 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 or heteroaryl having 5 to 20 ring atoms, or straight-chain or branched alkyl having 1 to 25 C atoms, in which one or more non-adjacent CH.sub.2 groups are optionally each 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 one or more H atoms are optionally replaced by F, Cl, CN, P or P-Sp-, R.sup.x denotes H, F, Cl, CN, or a straight chain, branched or cyclic alkyl having 1 to 25 C atoms, wherein one or more non-adjacent CH.sub.2-groups are optionally replaced by O, S, CO, COO, OCO, or OCOO in such a manner that O- and/or S-atoms are not directly connected with each other, and wherein one or more H atoms are each optionally replaced by F, Cl, P or P-Sp-, R.sup.0 and R.sup.00 each, independently of one another, denote H or alkyl having 1 to 20 C atoms, and Y.sup.1 is halogen.

3. The compound of claim 1, which is one of the following formulae ##STR00333## wherein R.sup.a, R.sup.b, P and Sp are as defined for the compound of formula I, and the benzene rings are optionally substituted by one or two groups L, wherein L denotes P, P-Sp-, F, Cl, 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 or heteroaryl having 5 to 20 ring atoms, or straight-chain or branched alkyl having 1 to 25 C atoms, in which one or more non-adjacent CH.sub.2 groups are optionally each 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 one or more H atoms are optionally replaced by F, Cl, CN, P or P-Sp-, R.sup.x denotes H, F, Cl, CN, or a straight chain, branched or cyclic alkyl having 1 to 25 C atoms, wherein one or more non-adjacent CH.sub.2-groups are optionally replaced by O, S, CO, COO, OCO, or OCOO in such a manner that O- and/or S-atoms are not directly connected with each other, and wherein one or more H atoms are each optionally replaced by F, Cl, P or P-Sp-, R.sup.0 and R.sup.00 each, independently of one another, denote H or alkyl having 1 to 20 C atoms, and Y.sup.1 is halogen.

4. The compound of claim 1, which is one of the following formulae ##STR00334## wherein P and Sp are as defined for the compound of formula I, and the benzene rings are optionally substituted by one or two groups L, wherein L denotes P, P-Sp-, F, Cl, 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 or heteroaryl having 5 to 20 ring atoms, or straight-chain or branched alkyl having 1 to 25 C atoms, in which one or more non-adjacent CH.sub.2 groups are optionally each 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 one or more H atoms are optionally replaced by F, Cl, CN, P or P-Sp-, R.sup.x denotes H, F, Cl, CN, or a straight chain, branched or cyclic alkyl having 1 to 25 C atoms, wherein one or more non-adjacent CH.sub.2-groups are optionally replaced by O, S, CO, COO, OCO, or OCOO in such a manner that O- and/or S-atoms are not directly connected with each other, and wherein one or more H atoms are each optionally replaced by F, Cl, P or P-Sp-, R.sup.0 and R.sup.00 each, independently of one another, denote H or alkyl having 1 to 20 C atoms, and Y.sup.1 is halogen.

5. The compound of claim 1, which is one of the following formulae ##STR00335## ##STR00336## ##STR00337## ##STR00338## wherein P.sup.1, P.sup.2 and P.sup.3 independently of each other have one of the meanings given for P for the compound of formula I, and Sp.sup.1, Sp.sup.2 and Sp.sup.3 independently of each other have one of the meanings given for Sp for the compound of formula I which is different from a single bond.

6. A liquid crystal (LC) medium comprising one or more polymerisable compounds of formula I of claim 1.

7. The LC medium of claim 6, comprising a polymerisable component A) comprising one or more polymerisable compounds of formula I, and a liquid-crystalline LC component B) comprising one or more mesogenic or liquid-crystalline compounds.

8. The LC medium of claim 6, comprising one or more compounds of formulae CY and/or PY ##STR00339## wherein a denotes 1 or 2, b denotes 0 or 1, ##STR00340## denotes ##STR00341## R.sup.1 and R.sup.2 each, independently of one another, denote alkyl having 1 to 12 C atoms, in which one or two non-adjacent CH.sub.2 groups are optionally replaced by O, CHCH, CO, OCO or COO in such a way that O atoms are not linked directly to one another, Z.sup.x denotes CHCH, CH.sub.2O, OCH.sub.2, OCF.sub.2, O, CH.sub.2, CH.sub.2CH.sub.2 or a single bond, and L.sup.1-4 each, independently of one another, denote F, Cl, OCF.sub.3, CF.sub.3, CH.sub.3, CH.sub.2F, or CHF.sub.2.

9. The LC medium of claim 7, comprising one or more compounds of the following formulae ##STR00342## in which ##STR00343## is each, on each occurrence identically or differently, and independently of one another, ##STR00344## is each, on each occurrence identically or differently, and independently of one another, ##STR00345## is each, on each occurrence identically or differently, and independently of one another, ##STR00346## R.sup.A1 is each, on each occurrence identically or differently, and independently of one another, alkenyl having 2 to 9 C atoms or, if at least one of the rings X, Y and Z denotes cyclohexenyl, also has one of the meanings of R.sup.A2, R.sup.A2 is each, on each occurrence identically or differently, and independently of one another, alkyl having 1 to 12 C atoms, in which one or two non-adjacent CH.sub.2 groups are optionally replaced by O, CHCH, CO, OCO or COO in such a way that O atoms are not linked directly to one another, Z.sup.x CH.sub.2CH.sub.2, CHCH, CF.sub.2O, OCF.sub.2, CH.sub.2O, OCH.sub.2, COO, OCO, C.sub.2F.sub.4, CFCF, CHCHCH.sub.2O, or a single bond, L.sup.1-4 each, independently of one another, H, F, Cl, OCF.sub.3, CF.sub.3, CH.sub.3, CH.sub.2F or CHF.sub.2H, x 1 or 2, z 0 or 1.

10. The LC medium of claim 6, comprising one or more compounds of the following formula ##STR00347## in which ##STR00348## denotes ##STR00349## denotes ##STR00350## R.sup.3 and R.sup.4 each, independently of one another, denote alkyl having 1 to 12 C atoms, in which one or two non-adjacent CH.sub.2 groups are optionally replaced by O, CHCH, CO, OCO or COO in such a way that O atoms are not linked directly to one another, Z.sup.y denotes CH.sub.2CH.sub.2, CHCH, CF.sub.2O, OCF.sub.2, CH.sub.2O, O CH.sub.2, COO, OCO, C.sub.2F.sub.4, CFCF or a single bond.

11. The LC medium of claim 6, in which the one or more polymerisable compounds of formula I are polymerised.

12. An LC display comprising one or more compounds of formula I of claim 1.

13. The LC display of claim 12, which is a PSA type display.

14. The LC display of claim 13, which is a PS-VA, PS-OCB, PS-IPS, PS-FFS, PS-UB-FFS, PS-posi-VA or PS-TN display.

15. The LC display of claim 13, comprising two substrates, at least one which is transparent to light, an electrode provided on each substrate or two electrodes provided on only one of the substrates, and located between the substrates a layer of an LC medium, which comprises one or more polymerisable compounds of formula I, wherein the polymerisable compounds are polymerised between the substrates of the display.

16. A process for the production of an LC display according to claim 15, comprising filling or otherwise providing an LC medium, which comprises one or more polymerisable compounds of formula I, between the substrates of the display, and polymerising the polymerisable compounds.

17. A compound of formula II ##STR00351## wherein A.sup.1, A.sup.2 denote, independently of each other, aryl or heteroaryl having 4 to 30 ring atoms, which is mono- or polycyclic and is optionally substituted, Sp denotes, on each occurrence identically or differently, a spacer group or a single bond, P denotes, on each occurrence identically or differently, a polymerisable group selected from the group consisting of CH.sub.2CW.sup.1COO, CH.sub.2CHO, (CH.sub.2CH).sub.2CHOCO, (CH.sub.2CH).sub.2CHO, ##STR00352## W.sup.1 denotes H, F, Cl, CN, CF.sub.3, phenyl or alkyl having 1 to 5 C atoms, W.sup.2 denotes H or alkyl having 1 to 5 C atoms, k.sub.1 denotes 0 or 1, and a, b denote, independently of each other, 0, 1 or 2, and Pg denotes OH, a protected hydroxyl group or a masked hydroxyl group.

18. A process for preparing a compound of formula I of claim 1, wherein P optionally denotes acrylate or methacrylate, comprising esterifying a compound of formula II ##STR00353## wherein A.sup.1, A.sup.2 denote, independently of each other, aryl or heteroaryl having 4 to 30 ring atoms, which is mono- or polycyclic and is optionally substituted, Sp denotes, on each occurrence identically or differently, a spacer group or a single bond, P denotes, on each occurrence identically or differently, a polymerisable group selected from the group consisting of CH.sub.2CW.sup.1COO, CH.sub.2CHO, (CH.sub.2CH).sub.2CHOCO, (CH.sub.2CH).sub.2CHO, ##STR00354## W.sup.1 denotes H, F, Cl or CH.sub.3, W.sup.2 denotes H or alkyl having 1 to 5 C atoms, k.sub.1 denotes 0 or 1, and a, b denote, independently of each other, 0, 1 or 2, and Pg denotes OH, by a corresponding acid, acid derivative, or halogenated compound containing a group P, in the presence of a dehydrating reagent.

19. A process of preparing an LC medium of claim 6, comprising mixing together one or more mesogenic or liquid-crystalline compounds, or a liquid-crystalline component B) which comprises one or more mesogenic or liquid-crystalline compounds, with one or more compounds of formula I, and optionally with further liquid-crystalline compounds and/or additives.

20. The compound of claim 1, wherein P denotes acrylate or methacrylate.

21. The compound of claim 1, wherein Sp denotes a single bond or (CH.sub.2).sub.p1, (CH.sub.2CH.sub.2O).sub.q1CH.sub.2CH.sub.2, CH.sub.2CH.sub.2SCH.sub.2CH.sub.2, CH.sub.2CH.sub.2NHCH.sub.2CH.sub.2 or (SiR.sup.0R.sup.00O).sub.p1, in which p1 is an integer from 1 to 12, q1 is an integer from 1 to 3, and R.sup.0 and R.sup.00 each, independently of one another, denote H or alkyl having 1 to 20 C atoms, and A.sup.1 and A.sup.2 are each independently benzene or naphthalene, wherein each benzene is independently optionally substituted by one or two groups L, and each naphthalene is independently optionally substituted by one or more groups L, and one of the benzene groups in formula I selected from the group consisting of the benzene group to which R.sup.a-(A.sup.1).sub.a- is bonded and the benzene group to which R.sup.b-(A.sup.2).sub.b- is bonded is optionally substituted by one or two groups L.

22. The compound of claim 21, wherein at least one benzene ring selected from the group consisting of the benzene group to which R.sup.a-(A.sup.1).sub.a- is bonded, the benzene group to which R.sup.b-(A.sup.2).sub.b- is bonded, the benzene group present as A.sup.1 and the benzene group present as A.sup.2 is substituted by one or two groups L, which L is F, Cl, CN, a straight-chain or branched alkyl having 1 to 25 C atoms, in which one or more non-adjacent CH.sub.2 groups are each optionally replaced, independently of one another, by C(R.sup.00)C(R.sup.000), CC, N(R.sup.00), 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 one or more H atoms are optionally replaced by F, Cl, Br, I or CN.

23. The compound of claim 1, wherein each of the benzene groups in the compound of formula I that are substituted by one or two groups L are of the following formula ##STR00355##

24. The compound of claim 1, which is one of the following compounds ##STR00356## ##STR00357##

25. The compound of claim 1, wherein none of the benzene groups in the compound of formula I are substituted by a L.

Description

DETAILED DESCRIPTION OF THE INVENTION

(1) Unless stated otherwise, the compounds of formula I are preferably selected from achiral compounds.

(2) As used herein, the terms active layer and switchable layer mean a layer in an electrooptical display, for example an LC display, that comprises one or more molecules having structural and optical anisotropy, like for example LC molecules, which change their orientation upon an external stimulus like an electric or magnetic field, resulting in a change of the transmission of the layer for polarized or unpolarized light.

(3) As used herein, the terms tilt and tilt angle will be understood to mean a tilted alignment of the LC molecules of an LC medium relative to the surfaces of the cell in an LC display (here preferably a PSA display). The tilt angle here denotes the average angle (<90) between the longitudinal molecular axes of the LC molecules (LC director) and the surface of the plane-parallel outer plates which form the LC cell. A low value for the tilt angle (i.e. a large deviation from the 90 angle) corresponds to a large tilt here. A suitable method for measurement of the tilt angle is given in the examples. Unless indicated otherwise, tilt angle values disclosed above and below relate to this measurement method.

(4) As used herein, the terms reactive mesogen and RM will be understood to mean a compound containing a mesogenic or liquid crystalline skeleton, and one or more functional groups attached thereto which are suitable for polymerisation and are also referred to as polymerisable group or P.

(5) Unless stated otherwise, the term polymerisable compound as used herein will be understood to mean a polymerisable monomeric compound.

(6) As used herein, the term low-molecular-weight compound will be understood to mean to a compound that is monomeric and/or is not prepared by a polymerisation reaction, as opposed to a polymeric compound or a polymer.

(7) As used herein, the term unpolymerisable compound will be understood to mean a compound that does not contain a functional group that is suitable for polymerisation under the conditions usually applied for the polymerisation of the RMs.

(8) The term mesogenic group as used herein is known to the person skilled in the art and described in the literature, and means a group which, due to the anisotropy of its attracting and repelling interactions, essentially contributes to causing a liquid-crystal (LC) phase in low-molecular-weight or polymeric substances. Compounds containing mesogenic groups (mesogenic compounds) do not necessarily have to have an LC phase themselves. It is also possible for mesogenic compounds to exhibit LC phase behaviour only after mixing with other compounds and/or after polymerisation. Typical mesogenic groups are, for example, rigid rod- or disc-shaped units. An overview of the terms and definitions used in connection with mesogenic or LC compounds is given in Pure Appl. Chem. 2001, 73(5), 888 and C. Tschierske, G. Pelzl, S. Diele, Angew. Chem. 2004, 116, 6340-6368.

(9) The term spacer group, hereinafter also referred to as Sp, as used herein is known to the person skilled in the art and is described in the literature, see, for example, Pure Appl. Chem. 2001, 73(5), 888 and C. Tschierske, G. Pelzl, S. Diele, Angew. Chem. 2004, 116, 6340-6368. As used herein, the terms spacer group or spacer mean a flexible group, for example an alkylene group, which connects the mesogenic group and the polymerisable group(s) in a polymerisable mesogenic compound.

(10) Above and below,

(11) ##STR00002##
denotes a trans-1,4-cyclohexylene ring, and

(12) ##STR00003##
denotes a 1,4-phenylene ring.

(13) Above and below organic group denotes a carbon or hydrocarbon group.

(14) Carbon group denotes a mono- or polyvalent organic group containing at least one carbon atom, where this either contains no further atoms (such as, for example, CC) or optionally contains one or more further atoms, such as, for example, N, O, S, B, P, Si, Se, As, Te or Ge (for example carbonyl, etc.). The term hydrocarbon group denotes a carbon group which additionally contains one or more H atoms and optionally one or more heteroatoms, such as, for example, N, O, S, B, P, Si, Se, As, Te or Ge.

(15) Halogen denotes F, Cl, Br or I.

(16) CO, C(O) and C(O) denote a carbonyl group, i.e.

(17) ##STR00004##

(18) A carbon or hydrocarbon group can be a saturated or unsaturated group. Unsaturated groups are, for example, aryl, alkenyl or alkynyl groups. A carbon or hydrocarbon radical having more than 3 C atoms can be straight-chain, branched and/or cyclic and may also contain spiro links or condensed rings.

(19) The terms alkyl, aryl, heteroaryl, etc., also encompass polyvalent groups, for example alkylene, arylene, heteroarylene, etc.

(20) The term aryl denotes an aromatic carbon group or a group derived therefrom. The term heteroaryl denotes aryl as defined above, containing one or more heteroatoms, preferably selected from N, O, S, Se, Te, Si and Ge.

(21) Preferred carbon and hydrocarbon groups are optionally substituted, straight-chain, branched or cyclic, alkyl, alkenyl, alkynyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy and alkoxycarbonyloxy having 1 to 40, preferably 1 to 20, very preferably 1 to 12, C atoms, optionally substituted aryl or aryloxy having 5 to 30, preferably 6 to 25, C atoms, or optionally substituted alkylaryl, arylalkyl, alkylaryloxy, arylalkyloxy, arylcarbonyl, aryloxycarbonyl, arylcarbonyloxy and aryloxycarbonyloxy having 5 to 30, preferably 6 to 25, C atoms, wherein one or more C atoms may also be replaced by hetero atoms, preferably selected from N, O, S, Se, Te, Si and Ge.

(22) Further preferred carbon and hydrocarbon groups are C.sub.1-C.sub.20 alkyl, C.sub.2-C.sub.20 alkenyl, C.sub.2-C.sub.20 alkynyl, C.sub.3-C.sub.20 allyl, C.sub.4-C.sub.20 alkyldienyl, C.sub.4-C.sub.20 polyenyl, C.sub.6-C.sub.20 cycloalkyl, C.sub.4-C.sub.15 cycloalkenyl, C.sub.6-C.sub.30 aryl, C.sub.6-C.sub.30 alkylaryl, C.sub.6-C.sub.30 arylalkyl, C.sub.6-C.sub.30 alkylaryloxy, C.sub.6-C.sub.30 arylalkyloxy, C.sub.2-C.sub.30 heteroaryl, C.sub.2-C.sub.30 heteroaryloxy.

(23) Particular preference is given to C.sub.1-C.sub.12 alkyl, C.sub.2-C.sub.12 alkenyl, C.sub.2-C.sub.12 alkynyl, C.sub.6-C.sub.25 aryl and C.sub.2-C.sub.25 heteroaryl.

(24) Further preferred carbon and hydrocarbon groups are straight-chain, branched or cyclic alkyl having 1 to 20, preferably 1 to 12, C atoms, which are unsubstituted or mono- or polysubstituted by F, Cl, Br, I or CN and in which one or more non-adjacent CH.sub.2 groups may each be replaced, independently of one another, by C(R.sup.xx)C(R.sup.xx), CC, N(R.sup.xx), O, S, CO, COO, OCO, OCOO in such a way that O and/or S atoms are not linked directly to one another.

(25) R.sup.xx preferably denotes H, F, Cl, CN, a straight-chain, branched or cyclic alkyl chain having 1 to 25 C atoms, in which, in addition, one or more non-adjacent C atoms may be replaced by O, S, CO, COO, OCO, OCOO and in which one or more H atoms may be replaced by F or Cl, or denotes an optionally substituted aryl or aryloxy group with 6 to 30 C atoms, or an optionally substituted heteroaryl or heteroaryloxy group with 2 to 30 C atoms.

(26) Preferred alkyl groups are, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, 2-methylbutyl, n-pentyl, s-pentyl, cyclopentyl, n-hexyl, cyclohexyl, 2-ethylhexyl, n-heptyl, cycloheptyl, n-octyl, cyclooctyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, dodecanyl, trifluoromethyl, perfluoro-n-butyl, 2,2,2-trifluoroethyl, perfluorooctyl, perfluorohexyl, etc.

(27) Preferred alkenyl groups are, for example, ethenyl, propenyl, butenyl, pentenyl, cyclopentenyl, hexenyl, cyclohexenyl, heptenyl, cycloheptenyl, octenyl, cyclooctenyl, etc.

(28) Preferred alkynyl groups are, for example, ethynyl, propynyl, butynyl, pentynyl, hexynyl, octynyl, etc.

(29) Preferred alkoxy groups are, for example, methoxy, ethoxy, 2-methoxy-ethoxy, n-propoxy, i-propoxy, n-butoxy, i-butoxy, s-butoxy, t-butoxy, 2-methylbutoxy, n-pentoxy, n-hexoxy, n-heptoxy, n-octoxy, n-nonoxy, n-decoxy, n-undecoxy, n-dodecoxy, etc.

(30) Preferred amino groups are, for example, dimethylamino, methylamino, methylphenylamino, phenylamino, etc.

(31) Aryl and heteroaryl groups can be monocyclic or polycyclic, i.e. they can contain one ring (such as, for example, phenyl) or two or more rings, which may also be fused (such as, for example, naphthyl) or covalently bonded (such as, for example, biphenyl), or contain a combination of fused and linked rings. Heteroaryl groups contain one or more heteroatoms, preferably selected from O, N, S and Se.

(32) Particular preference is given to mono-, bi- or tricyclic aryl groups having 6 to 25 C atoms and mono-, bi- or tricyclic heteroaryl groups having 5 to 25 ring atoms, which optionally contain fused rings and are optionally substituted. Preference is furthermore given to 5-, 6- or 7-membered aryl and heteroaryl groups, in which, in addition, one or more CH groups may be replaced by N, S or O in such a way that O atoms and/or S atoms are not linked directly to one another.

(33) Preferred aryl groups are, for example, phenyl, biphenyl, terphenyl, [1,1:3,1]terphenyl-2-yl, naphthyl, anthracene, binaphthyl, phenanthrene, 9,10-dihydro-phenanthrene, pyrene, dihydropyrene, chrysene, perylene, tetracene, pentacene, benzopyrene, fluorene, indene, indenofluorene, spirobifluorene, etc.

(34) Preferred heteroaryl groups are, for example, 5-membered rings, such as pyrrole, pyrazole, imidazole, 1,2,3-triazole, 1,2,4-triazole, tetrazole, furan, thiophene, selenophene, oxazole, isoxazole, 1,2-thiazole, 1,3-thiazole, 1,2,3-oxadiazole, 1,2,4-oxadiazole, 1,2,5-oxadiazole, 1,3,4-oxadiazole, 1,2,3-thiadiazole, 1,2,4-thiadiazole, 1,2,5-thiadiazole, 1,3,4-thiadiazole, 6-membered rings, such as pyridine, pyridazine, pyrimidine, pyrazine, 1,3,5-triazine, 1,2,4-triazine, 1,2,3-triazine, 1,2,4,5-tetrazine, 1,2,3,4-tetrazine, 1,2,3,5-tetrazine, or condensed groups, such as indole, isoindole, indolizine, indazole, benzimidazole, benzotriazole, purine, naphthimidazole, phenanthrimidazole, pyridimidazole, pyrazinimidazole, quinoxalinimidazole, benzoxazole, naphthoxazole, anthroxazole, phenanthroxazole, isoxazole, benzothiazole, benzofuran, isobenzofuran, dibenzofuran, quinoline, isoquinoline, pteridine, benzo-5,6-quinoline, benzo-6,7-quinoline, benzo-7,8-quinoline, benzoisoquinoline, acridine, phenothiazine, phenoxazine, benzopyridazine, benzopyrimidine, quinoxaline, phenazine, naphthyridine, azacarbazole, benzocarboline, phenanthridine, phenanthroline, thieno[2,3b]thiophene, thieno[3,2b]thiophene, dithienothiophene, isobenzothiophene, dibenzothiophene, benzothiadiazothiophene, or combinations of these groups.

(35) The aryl and heteroaryl groups mentioned above and below may also be substituted by alkyl, alkoxy, thioalkyl, fluorine, fluoroalkyl or further aryl or heteroaryl groups.

(36) The (non-aromatic) alicyclic and heterocyclic groups encompass both saturated rings, i.e. those containing exclusively single bonds, and also partially unsaturated rings, i.e. those which may also contain multiple bonds. Heterocyclic rings contain one or more heteroatoms, preferably selected from Si, O, N, S and Se.

(37) The (non-aromatic) alicyclic and heterocyclic groups can be monocyclic, i.e. contain only one ring (such as, for example, cyclohexane), or polycyclic, i.e. contain a plurality of rings (such as, for example, decahydronaphthalene or bicyclooctane). Particular preference is given to saturated groups. Preference is furthermore given to mono-, bi- or tricyclic groups having 5 to 25 ring atoms, which optionally contain fused rings and are optionally substituted. Preference is furthermore given to 5-, 6-, 7- or 8-membered carbocyclic groups, in which, in addition, one or more C atoms may be replaced by Si and/or one or more CH groups may be replaced by N and/or one or more non-adjacent CH.sub.2 groups may be replaced by O and/or S.

(38) Preferred alicyclic and heterocyclic groups are, for example, 5-membered groups, such as cyclopentane, tetrahydrofuran, tetrahydrothiofuran, pyrrolidine, 6-membered groups, such as cyclohexane, silinane, cyclohexene, tetrahydropyran, tetrahydrothiopyran, 1,3-dioxane, 1,3-dithiane, piperidine, 7-membered groups, such as cycloheptane, and fused groups, such as tetrahydronaphthalene, decahydronaphthalene, indane, bicyclo[1.1.1]-pentane-1,3-diyl, bicyclo[2.2.2]octane-1,4-diyl, spiro[3.3]heptane-2,6-diyl, octahydro-4,7-methanoindane-2,5-diyl.

(39) Preferred substituents are, for example, solubility-promoting groups, such as alkyl or alkoxy, electron-withdrawing groups, such as fluorine, nitro or nitrile, or substituents for increasing the glass transition temperature (Tg) in the polymer, in particular bulky groups, such as, for example, t-butyl or optionally substituted aryl groups.

(40) Preferred substituents, hereinafter also referred to as L, are, for example, F, Cl, Br, I, 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, straight-chain or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy each having 1 to 25 C atoms, in which one or more H atoms may optionally be replaced by F or Cl, optionally substituted silyl having 1 to 20 Si atoms, or optionally substituted aryl having 6 to 25, preferably 6 to 15, C atoms,

(41) wherein R.sup.x denotes H, F, Cl, CN, or straight chain, branched or cyclic alkyl having 1 to 25 C atoms, wherein one or more non-adjacent CH.sub.2-groups are optionally replaced by O, S, CO, COO, OCO, OCOO in such a manner that O- and/or S-atoms are not directly connected with each other, and wherein one or more H atoms are each optionally replaced by F, Cl, P or P-Sp-, and

(42) Y.sup.1 denotes halogen.

(43) Substituted silyl or aryl preferably means substituted by halogen, CN, R.sup.0, OR.sup.0, COR.sup.0, COOR.sup.0, OCOR.sup.0 or OCOOR.sup.0, wherein R.sup.0 denotes H or alkyl with 1 to 20 C atoms.

(44) Particularly preferred substituents L are, for example, F, Cl, CN, NO.sub.2, CH.sub.3, C.sub.2H.sub.5, OCH.sub.3, OC.sub.2H.sub.5, COCH.sub.3, COC.sub.2H.sub.5, COOCH.sub.3, COOC.sub.2H.sub.5, CF.sub.3, OCF.sub.3, OCHF.sub.2, OC.sub.2F.sub.5, furthermore phenyl.

(45) ##STR00005##
is preferably

(46) ##STR00006##
in which L has one of the meanings indicated above.

(47) The polymerisable group P is a group which is suitable for a polymerisation reaction, such as, for example, free-radical or ionic chain polymerisation, polyaddition or polycondensation, or for a polymer-analogous reaction, for example addition or condensation onto a main polymer chain. Particular preference is given to groups for chain polymerisation, in particular those containing a CC double bond or CC triple bond, and groups which are suitable for polymerisation with ring opening, such as, for example, oxetane or epoxide groups.

(48) Preferred groups P are selected from the group consisting of CH.sub.2CW.sup.1COO, CH.sub.2CW.sup.1CO,

(49) ##STR00007##
CH.sub.2CW.sup.2(O).sub.k3, CW.sup.1CHCO(O).sub.k3, CW.sup.1CHCONH, CH.sub.2CW.sup.1CONH, CH.sub.3CHCHO, (CH.sub.2CH).sub.2CHOCO, (CH.sub.2CHCH.sub.2).sub.2CHOCO, (CH.sub.2CH).sub.2CHO, (CH.sub.2CHCH.sub.2).sub.2N, (CH.sub.2CHCH.sub.2).sub.2NCO, HOCW.sup.2W.sup.3, HSCW.sup.2W.sup.3, HW.sup.2N, HOCW.sup.2W.sup.3NH, CH.sub.2CW.sup.1CONH, CH.sub.2CH(COO).sub.k1-Phe-(O).sub.k2, CH.sub.2CH(CO).sub.k1-Phe-(O).sub.k2, Phe-CHCH, HOOC, OCN and W.sup.4W.sup.5W.sup.6Si, in which W.sup.1 denotes H, F, Cl, CN, CF.sub.3, phenyl or alkyl having 1 to 5 C atoms, in particular H, F, Cl or CH.sub.3, W.sup.2 and W.sup.3 each, independently of one another, denote H or alkyl having 1 to 5 C atoms, in particular H, methyl, ethyl or n-propyl, W.sup.4, W.sup.5 and W.sup.6 each, independently of one another, denote Cl, oxaalkyl or oxacarbonylalkyl having 1 to 5 C atoms, W.sup.7 and W.sup.8 each, independently of one another, denote H, Cl or alkyl having 1 to 5 C atoms, Phe denotes 1,4-phenylene, which is optionally substituted by one or more radicals L as defined above which are other than P-Sp-, k.sub.1, k.sub.2 and k.sub.3 each, independently of one another, denote 0 or 1, k.sub.3 preferably denotes 1, and k.sub.4 denotes an integer from 1 to 10.

(50) Very preferred groups P are selected from the group consisting of CH.sub.2CW.sup.1COO, CH.sub.2CW.sup.1CO,

(51) ##STR00008##
CH.sub.2CW.sup.2O, CH.sub.2CW.sup.2, CW.sup.1CHCO(O).sub.k3, CW.sup.1CHCONH, CH.sub.2CW.sup.1CONH, (CH.sub.2CH).sub.2CHOCO, (CH.sub.2CHCH.sub.2).sub.2CHOCO, (CH.sub.2CH).sub.2CHO, (CH.sub.2CHCH.sub.2).sub.2N, (CH.sub.2CHCH.sub.2).sub.2NCO, CH.sub.2CW.sup.1CONH, CH.sub.2CH(COO).sub.k1-Phe-(O).sub.k2, CH.sub.2CH(CO).sub.k1-Phe-(O).sub.k2, Phe-CHCH and W.sup.4W.sup.5W.sup.6Si, in which W.sup.1 denotes H, F, Cl, CN, CF.sub.3, phenyl or alkyl having 1 to 5 C atoms, in particular H, F, Cl or CH.sub.3, W.sup.2 and W.sup.3 each, independently of one another, denote H or alkyl having 1 to 5 C atoms, in particular H, methyl, ethyl or n-propyl, W.sup.4, W.sup.5 and W.sup.6 each, independently of one another, denote Cl, oxaalkyl or oxacarbonylalkyl having 1 to 5 C atoms, W.sup.7 and W.sup.8 each, independently of one another, denote H, Cl or alkyl having 1 to 5 C atoms, Phe denotes 1,4-phenylene, k.sub.1, k.sub.2 and k.sub.3 each, independently of one another, denote 0 or 1, k.sub.3 preferably denotes 1, and k.sub.4 denotes an integer from 1 to 10.

(52) Very particularly preferred groups P are selected from the group consisting of CH.sub.2CW.sup.1COO, in particular CH.sub.2CHCOO, CH.sub.2C(CH.sub.3)COO and CH.sub.2CFCOO, furthermore CH.sub.2CHO, (CH.sub.2CH).sub.2CHOCO, (CH.sub.2CH).sub.2CHO,

(53) ##STR00009##

(54) Further preferred polymerisable groups P are selected from the group consisting of vinyloxy, acrylate, methacrylate, fluoroacrylate, chloroacrylate, oxetane and epoxide, most preferably from acrylate and methacrylate.

(55) If Sp is different from a single bond, it is preferably of the formula Sp-X, so that the respective radical P-Sp- conforms to the formula P-Sp-X, wherein Sp denotes alkylene having 1 to 20, preferably 1 to 12, C atoms, which is optionally mono- or polysubstituted by F, Cl, Br, I or CN and in which, in addition, one or more non-adjacent CH.sub.2 groups may each be replaced, independently of one another, by O, S, NH, N(R.sup.0), Si(R.sup.0R.sup.00), CO, COO, OCO, OCOO, SCO, COS, N(R.sup.00)COO, OCON(R.sup.0), N(R.sup.0)CON(R.sup.00), CHCH or CC in such a way that O and/or S atoms are not linked directly to one another, X denotes O, S, CO, COO, OCO, OCOO, CON(R.sup.0), N(R.sup.0)CO, N(R.sup.0)CON(R.sup.00), OCH.sub.2, CH.sub.2O, SCH.sub.2, CH.sub.2S, CF.sub.2O, OCF.sub.2, CF.sub.2S, SCF.sub.2, CF.sub.2CH.sub.2, CH.sub.2CF.sub.2, CF.sub.2CF.sub.2, CHN, NCH, NN, CHCR.sup.0, CY.sup.2CY.sup.3, CC, CHCHCOO, OCOCHCH or a single bond, R.sup.0 and R.sup.00 each, independently of one another, denote H or alkyl having 1 to 20 C atoms, and Y.sup.2 and Y.sup.3 each, independently of one another, denote H, F, Cl or CN. X is preferably O, S, CO, COO, OCO, OCOO, CONR.sup.0, NR.sup.0CO, NR.sup.0CONR.sup.00 or a single bond.

(56) Typical spacer groups Sp and -Sp-X are, for example, (CH.sub.2).sub.p1, (CH.sub.2CH.sub.2O).sub.q1CH.sub.2CH.sub.2, CH.sub.2CH.sub.2SCH.sub.2CH.sub.2, CH.sub.2CH.sub.2NHCH.sub.2CH.sub.2 or (SiR.sup.0R.sup.00O).sub.p1, in which p1 is an integer from 1 to 12, q1 is an integer from 1 to 3, and R.sup.0 and R.sup.00 have the meanings indicated above.

(57) Particularly preferred groups Sp and -Sp-X are (CH.sub.2).sub.p1, (CH.sub.2).sub.p1O, (CH.sub.2).sub.p1OCO, (CH.sub.2).sub.p1COO, (CH.sub.2).sub.p1OCOO, in which p1 and q1 have the meanings indicated above.

(58) Particularly preferred groups Sp are, in each case straight-chain, ethylene, propylene, butylene, pentylene, hexylene, heptylene, octylene, nonylene, decylene, undecylene, dodecylene, octadecylene, ethyleneoxyethylene, methyleneoxybutylene, ethylenethioethylene, ethylene-N-methylimino-ethylene, 1-methylalkylene, ethenylene, propenylene and butenylene.

(59) In the compounds of formula I A.sup.1 and A.sup.2 denote an aromatic or heteroaromatic group which is monocyclic or polycyclic, has 4 to 30 ring atoms, and is unsubstituted or substituted by one or more substituents, said substituents preferably selected from L, wherein L denotes P-Sp-, F, Cl, 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 or heteroaryl having 5 to 20 ring atoms, or straight-chain or branched alkyl having 1 to 25, particularly preferably 1 to 10, 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, 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, P or P-Sp-, R.sup.x denotes H, F, Cl, CN, or straight chain, branched or cyclic alkyl having 1 to 25 C atoms, wherein one or more non-adjacent CH.sub.2-groups are optionally replaced by O, S, CO, COO, OCO, OCOO in such a manner that O- and/or S-atoms are not directly connected with each other, and wherein one or more H atoms are each optionally replaced by F, Cl, P or P-Sp-, and R.sup.0 and R.sup.00 each, independently of one another, denote H or alkyl having 1 to 20 C atoms, and Y.sup.1 is halogen.

(60) Preferably A.sup.1 and A.sup.1 are selected from benzene and naphthalene which are optionally substituted by one or more groups L.

(61) Preferred compounds of formula I are those wherein at least one of R.sup.a and R.sup.b, very preferably both R.sup.a and R.sup.b, denote P-Sp-. Accordingly these preferred compounds are selected from the following subformulae

(62) ##STR00010##
wherein P, Sp, A.sup.1, A.sup.2, a and b are as defined in formula I. Very preferred compounds are those of formula IA.

(63) Preferred compounds of formula I are selected from the following formulae

(64) ##STR00011##
wherein R.sup.a, R.sup.b, P and Sp are as defined in formula I, and the benzene rings are optionally substituted by one or more groups L as defined above, and preferably at least one of R.sup.a and R.sup.b, very preferably both R.sup.a and R.sup.b denote P-Sp-.

(65) Very preferred compounds of formula I are selected from the following subformulae:

(66) ##STR00012##
wherein P and Sp are as defined in formula I, and the benzene rings are optionally substituted by one or more groups L as defined above.

(67) Further preferred compounds of formula I are selected from the following subformulae:

(68) ##STR00013## ##STR00014## ##STR00015##
wherein P.sup.1, P.sup.2 and P.sup.3 independently of each other have one of the meanings given for P in formula I or of its preferred meanings given above and below, and Sp.sup.1, Sp.sup.2 and Sp.sup.3 independently of each other have one of the meanings given for Sp in formula I, or of its preferred meanings given above and below, which is different from a single bond. Especially preferably in these preferred formulae P.sup.1, P.sup.2 and P.sup.3 are independently of each other selected from acrylate and methacrylate groups, and Sp.sup.1, Sp.sup.2 and Sp.sup.3 are independently of each other selected from ethylene, n-propylene, n-butylene, n-pentylene and n-hexylene.

(69) Very preferred are compounds of formulae I1a1, I1a2, I2a5, I3a5, I4a1, I4a2, I5a1 and I5a2.

(70) Further preferred compounds of formula I and its subformulae IA-IC, I1-I5, I1a-I5a and I1a1-I5a4 are those selected from the following preferred embodiments, including any combination thereof: a is 0 and b is 1, or a is 1 and b is 0, a is 0 and b is 0, P, P.sup.1, P.sup.2 and P.sup.3 are selected from the group consisting of acrylate, methacrylate and oxetane, at least one group Sp is different from a single bond, one or two groups Sp are different from a single bond, the compounds contain exactly three polymerisable groups (represented by the groups P or P.sup.1, P.sup.2 and P.sup.3), L does not denote or contain a polymerisable group, L does not denote or contain a group P-Sp-, at least one of the benzene rings in formula I and its subformulae is substituted by a group L that denotes P-Sp-, at least one of the benzene rings in formula I and its subformulae is substituted by a group L that is different from P-Sp- and is not polymerisable, and is preferably selected from F, Cl, CN and straight-chain or branched alkyl having 1 to 25, particularly preferably 1 to 10, 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.00)C(R.sup.000), CC, N(R.sup.00), O, S, CO, COO, OCO, 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, Br, I or CN, at least one of the benzene rings in formula I and its subformulae is substituted by one or two substituents selected from F, CN, and alkyl or alkoxy with 1 to 6 C atoms that is optionally fluorinated.

(71) The invention furthermore relates to compounds of formula II

(72) ##STR00016##
wherein Sp, A.sup.1, A.sup.2, a and b are as defined in formula I, and Pg denotes OH, a protected hydroxyl group or a masked hydroxyl group.

(73) Preferred compounds of formula II are selected from subformulae IA-IC, I1-I5, I1a-I5a and I1a1-I5a4 as defined above, wherein P is replaced by Pg.

(74) Suitable protected hydroxyl groups Pg are known to the person skilled in the art. Preferred protecting groups for hydroxyl groups are alkyl, alkoxyalkyl, acyl, alkylsilyl, arylsilyl and arylmethyl groups, especially 2-tetrahydropyranyl, methoxymethyl, methoxyethoxymethyl, acetyl, triisopropylsilyl, tert-butyl-dimethylsilyl or benzyl.

(75) The term masked hydroxyl group is understood to mean any functional group that can be chemically converted into a hydroxyl group. Suitable masked hydroxyl groups Pg are known to the person skilled in the art.

(76) The compounds of formula II are suitable as intermediates for the preparation of compounds of the formula I and its subformulae.

(77) The invention further relates to the use of the compounds of formula II as intermediates for the preparation of compounds of the formula I and its subformulae.

(78) The compounds and intermediates of the formulae I and II and sub-formulae thereof can be prepared analogously to processes known to the person skilled in the art and described in standard works of organic chemistry, such as, for example, in Houben-Weyl, Methoden der organischen Chemie [Methods of Organic Chemistry], Thieme-Verlag, Stuttgart.

(79) For example, compounds of formula I can be synthesised by esterification or etherification of the intermediates of formula II, wherein Pg denote OH, using corresponding acids, acid derivatives, or halogenated compounds containing a polymerisable group P.

(80) For example, acrylic or methacrylic esters can be prepared by esterification of the corresponding alcohols with acid derivatives like, for example, (meth)acryloyl chloride or (meth)acrylic anhydride in the presence of a base like pyridine or triethyl amine, and 4-(N,N-dimethylamino)pyridine (DMAP). Alternatively the esters can be prepared by esterification of the alcohols with (meth)acrylic acid in the presence of a dehydrating reagent, for example according to Steglich with dicyclohexylcarbodiimide (DCC), N-(3-dimethylaminopropyl)-N-ethylcarbodiimide (EDC) or N-(3-dimethylaminopropyl)-N-ethylcarbodiimide hydrochloride and DMAP.

(81) Further suitable methods are shown in the Examples.

(82) For the production of PSA displays, the polymerisable compounds contained in the LC medium are polymerised or crosslinked (if one compound contains two or more polymerisable groups) by in-situ polymerisation in the LC medium between the substrates of the LC display, optionally while a voltage is applied to the electrodes.

(83) The structure of the PSA displays according to the invention corresponds to the usual geometry for PSA displays, as described in the prior art cited at the outset. Geometries without protrusions are preferred, in particular those in which, in addition, the electrode on the colour filter side is unstructured and only the electrode on the TFT side has slots. Particularly suitable and preferred electrode structures for PS-VA displays are described, for example, in US 2006/0066793 A1.

(84) A preferred PSA type LC display of the present invention comprises: a first substrate including a pixel electrode defining pixel areas, the pixel electrode being connected to a switching element disposed in each pixel area and optionally including a micro-slit pattern, and optionally a first alignment layer disposed on the pixel electrode, a second substrate including a common electrode layer, which may be disposed on the entire portion of the second substrate facing the first substrate, and optionally a second alignment layer, an LC layer disposed between the first and second substrates and including an LC medium comprising a polymerisable component A and a liquid crystal component B as described above and below, wherein the polymerisable component A may also be polymerised.

(85) The first and/or second alignment layer controls the alignment direction of the LC molecules of the LC layer. For example, in PS-VA displays the alignment layer is selected such that it imparts to the LC molecules homeotropic (or vertical) alignment (i.e. perpendicular to the surface) or tilted alignment. Such an alignment layer may for example comprise a polyimide, which may also be rubbed, or may be prepared by a photoalignment method.

(86) The LC layer with the LC medium can be deposited between the substrates of the display by methods that are conventionally used by display manufacturers, for example the so-called one-drop-filling (ODF) method. The polymerisable component of the LC medium is then polymerised for example by UV photopolymerisation. The polymerisation can be carried out in one step or in two or more steps.

(87) The PSA display may comprise further elements, like a colour filter, a black matrix, a passivation layer, optical retardation layers, transistor elements for addressing the individual pixels, etc., all of which are well known to the person skilled in the art and can be employed without inventive skill.

(88) The electrode structure can be designed by the skilled person depending on the individual display type. For example for PS-VA displays a multi-domain orientation of the LC molecules can be induced by providing electrodes having slits and/or bumps or protrusions in order to create two, four or more different tilt alignment directions.

(89) Upon polymerisation the polymerisable compounds form a crosslinked polymer, which causes a certain pretilt of the LC molecules in the LC medium. Without wishing to be bound to a specific theory, it is believed that at least a part of the crosslinked polymer, which is formed by the polymerisable compounds, will phase-separate or precipitate from the LC medium and form a polymer layer on the substrates or electrodes, or the alignment layer provided thereon. Microscopic measurement data (like SEM and AFM) have confirmed that at least a part of the formed polymer accumulates at the LC/substrate interface.

(90) The polymerisation can be carried out in one step. It is also possible firstly to carry out the polymerisation, optionally while applying a voltage, in a first step in order to produce a pretilt angle, and subsequently, in a second polymerisation step without an applied voltage, to polymerise or crosslink the compounds which have not reacted in the first step (end curing).

(91) Suitable and preferred polymerisation methods are, for example, thermal or photopolymerisation, preferably photopolymerisation, in particular UV induced photopolymerisation, which can be achieved by exposure of the polymerisable compounds to UV radiation.

(92) Optionally one or more polymerisation initiators are added to the LC medium. Suitable conditions for the polymerisation and suitable types and amounts of initiators are known to the person skilled in the art and are described in the literature. Suitable for free-radical polymerisation are, for example, the commercially available photoinitiators Irgacure651, Irgacure184, Irgacure907, Irgacure369 or Darocure1173 (Ciba AG). If a polymerisation initiator is employed, its proportion is preferably 0.001 to 5% by weight, particularly preferably 0.001 to 1% by weight.

(93) The polymerisable compounds according to the invention are also suitable for polymerisation without an initiator, which is accompanied by considerable advantages, such, for example, lower material costs and in particular less contamination of the LC medium by possible residual amounts of the initiator or degradation products thereof. The polymerisation can thus also be carried out without the addition of an initiator. In a preferred embodiment, the LC medium thus does not contain a polymerisation initiator.

(94) The LC medium may also comprise one or more stabilisers in order to prevent undesired spontaneous polymerisation of the RMs, for example during storage or transport. Suitable types and amounts of stabilisers are known to the person skilled in the art and are described in the literature. Particularly suitable are, for example, the commercially available stabilisers from the Irganox series (Ciba AG), such as, for example, Irganox 1076. If stabilisers are employed, their proportion, based on the total amount of RMs or the polymerisable component (component A), is preferably 10-500,000 ppm, particularly preferably 50-50,000 ppm.

(95) The polymerisable compounds of formula I do in particular show good UV absorption in, and are therefore especially suitable for, a process of preparing a PSA display including one or more of the following features: the polymerisable medium is exposed to UV light in the display in a 2-step process, including a first UV exposure step (UV-1 step) to generate the tilt angle, and a second UV exposure step (UV-2 step) to finish polymerization, the polymerisable medium is exposed to UV light in the display generated by an energy-saving UV lamp (also known as green UV lamps). These lamps are characterized by a relative low intensity ( 1/100- 1/10 of a conventional UV1 lamp) in their absorption spectra from 300-380 nm, and are preferably used in the UV2 step, but are optionally also used in the UV1 step when avoiding high intensity is necessary for the process. the polymerisable medium is exposed to UV light in the display generated by a UV lamp with a radiation spectrum that is shifted to longer wavelengths, preferably 340 nm or more, to avoid short UV light exposure in the PS-VA process.

(96) Both using lower intensity and a UV shift to longer wavelengths protect the organic layer against damage that may be caused by the UV light.

(97) A preferred embodiment of the present invention relates to a process for preparing a PSA display as described above and below, comprising one or more of the following features: the polymerisable LC medium is exposed to UV light in a 2-step process, including a first UV exposure step (UV-1 step) to generate the tilt angle, and a second UV exposure step (UV-2 step) to finish polymerization, the polymerisable LC medium is exposed to UV light generated by a UV lamp having an intensity of from 0.5 mW/cm.sup.2 to 10 mW/cm.sup.2 in the wavelength range from 300-380 nm, preferably used in the UV2 step, and optionally also in the UV1 step, the polymerisable LC medium is exposed to UV light having a wavelength of 340 nm or more, and preferably 400 nm or less.

(98) This preferred process can be carried out for example by using the desired UV lamps or by using a band pass filter and/or a cut-off filter, which are substantially transmissive for UV light with the respective desired wavelength(s) and are substantially blocking light with the respective undesired wavelengths. For example, when irradiation with UV light of wavelengths of 300-400 nm is desired, UV exposure can be carried out using a wide band pass filter being substantially transmissive for wavelengths 300 nm<<400 nm. When irradiation with UV light of wavelength of more than 340 nm is desired, UV exposure can be carried out using a cut-off filter being substantially transmissive for wavelengths >340 nm.

(99) Substantially transmissive means that the filter transmits a substantial part, preferably at least 50% of the intensity, of incident light of the desired wavelength(s). Substantially blocking means that the filter does not transmit a substantial part, preferably at least 50% of the intensity, of incident light of the undesired wavelengths. Desired (undesired) wavelength e.g. in case of a band pass filter means the wavelengths inside (outside) the given range of , and in case of a cut-off filter means the wavelengths above (below) the given value of .

(100) This preferred process enables the manufacture of displays by using longer UV wavelengths, thereby reducing or even avoiding the hazardous and damaging effects of short UV light components.

(101) UV radiation energy is in general from 6 to 100 J, depending on the production process conditions.

(102) Preferably the LC medium according to the present invention does essentially consist of a polymerisable component A) and an LC component B), or LC host mixture, as described above and below. However, the LC medium may additionally comprise one or more further components or additives, preferably selected from the list including but not limited to co-monomers, chiral dopants, polymerisation initiators, inhibitors, stabilizers, surfactants, wetting agents, lubricating agents, dispersing agents, hydrophobing agents, adhesive agents, flow improvers, defoaming agents, deaerators, diluents, reactive diluents, auxiliaries, colourants, dyes, pigments and nanoparticles.

(103) Particular preference is given to LC media comprising one, two or three polymerisable compounds of formula I.

(104) Preference is furthermore given to LC media in which the polymerisable component A) comprises exclusively polymerisable compounds of formula I.

(105) Preference is furthermore given to LC media in which the LC component B), or the LC host mixture, has a nematic LC phase, and preferably has no chiral liquid crystal phase.

(106) Preference is furthermore given to achiral compounds of formula I, and to LC media in which the compounds of component A and/or B are selected exclusively from the group consisting of achiral compounds.

(107) Preferably the proportion of the polymerisable component A) in the LC medium is from >0 to <5%, very preferably from >0 to <1%, most preferably from 0.01 to 0.5%.

(108) Preferably the proportion of compounds of formula I in the LC medium is from >0 to <5%, very preferably from >0 to <1%, most preferably from 0.01 to 0.5%.

(109) Preferably the proportion of the LC component B) in the LC medium is from 95 to <100%, very preferably from 99 to <100%.

(110) In a preferred embodiment the polymerisable compounds of the polymerisable component A) are exclusively selected from formula I.

(111) In another preferred embodiment the polymerisable component A) comprises, in addition to the compounds of formula I, one or more further polymerisable compounds (co-monomers), preferably selected from RMs.

(112) Suitable and preferred mesogenic comonomers are selected from the following formulae:

(113) ##STR00017## ##STR00018## ##STR00019## ##STR00020##
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 an acrylate or methacrylate group, Sp.sup.1, Sp.sup.2 and Sp.sup.3 each, independently of one another, denote a single bond or a spacer group having one of the meanings indicated above and below for Sp.sup.1, and particularly preferably denote (CH.sub.2).sub.p1, (CH.sub.2).sub.p1O, (CH.sub.2).sub.p1COO , (CH.sub.2).sub.p1OCO or (CH.sub.2).sub.p1OCOO, in which p1 is an integer from 1 to 12, where, in addition, one or more of the radicals P.sup.1-Sp.sup.1-, P.sup.1-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 is different from 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, 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-, particularly preferably straight-chain or branched, optionally mono- or polyfluorinated alkyl, alkoxy, alkenyl, alkynyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy 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), R.sup.0, 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 mono- or polyfluorinated alkyl, alkoxy, alkenyl, alkynyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 12 C atoms, preferably F, 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, x denotes 0 or 1.

(114) Especially preferred are compounds of formulae M2, M13, M17, M22, M23 and M29.

(115) Further preferred are trireactive compounds M15 to M30, in particular M17, M18, M19, M22, M23, M24, M25, M29 and M30.

(116) In the compounds of formulae M1 to M30 the group

(117) ##STR00021##
is preferably

(118) ##STR00022##
wherein L on each occurrence, identically or differently, has one of the meanings given above or below, and is preferably F, Cl, CN, NO.sub.2, CH.sub.3, C.sub.2H.sub.5, C(CH.sub.3).sub.3, CH(CH.sub.3).sub.2, CH.sub.2CH(CH.sub.3)C.sub.2H.sub.5, OCH.sub.3, OC.sub.2H.sub.5, COCH.sub.3, COC.sub.2H.sub.5, COOCH.sub.3, COOC.sub.2H.sub.5, CF.sub.3, OCF.sub.3, OCHF.sub.2, OC.sub.2F.sub.5 or P-Sp-, very preferably F, Cl, CN, CH.sub.3, C.sub.2H.sub.5, OCH.sub.3, COCH.sub.3, OCF.sub.3 or P-Sp-, more preferably F, Cl, CH.sub.3, OCH.sub.3, COCH.sub.3 oder OCF.sub.3, especially F or CH.sub.3.

(119) Besides the polymerisable compounds described above, the LC media for use in the LC displays according to the invention comprise an LC component B), or LC host mixture comprising, or consisting of, one or more, preferably two or more LC compounds which are selected from low-molecular-weight compounds that are unpolymerisable. These LC compounds are selected such that they stable and/or unreactive to a polymerisation reaction under the conditions applied to the polymerisation of the polymerisable compounds.

(120) In principle, any LC mixture which is suitable for use in conventional displays is suitable as host mixture. Suitable LC mixtures are known to the person skilled in the art and are described in the literature, for example mixtures in VA displays in EP 1 378 557 A1 and mixtures for OCB displays in EP 1 306 418 A1 and DE 102 24 046 A1.

(121) In addition to the polymerisable compounds the LC medium according to the present invention comprises one or more mesogenic or liquid crystalline compounds comprising an alkenyl group, (alkenyl compound), where this alkenyl group is preferably stable to a polymerisation reaction under the conditions used for the polymerisation of the polymerisable compounds of formula I or of the other polymerisable compounds contained in the LC medium.

(122) The polymerisable compounds of formula I are especially suitable for use in an LC host mixture that comprises one or more mesogenic or LC compounds comprising an alkenyl group (hereinafter also referred to as alkenyl compounds), wherein said alkenyl group is stable to a polymerisation reaction under the conditions used for polymerisation of the compounds of formula I and of the other polymerisable compounds contained in the LC medium. Compared to RMs known from prior art the compounds of formula I do in such an LC host mixture exhibit improved properties, like solubility, reactivity or capability of generating a tilt angle.

(123) The LC host mixture is preferably a nematic LC mixture.

(124) The alkenyl groups in the alkenyl compounds are preferably selected from straight-chain, branched or cyclic alkenyl, in particular having 2 to 25 C atoms, particularly preferably having 2 to 12 C atoms, in which, in addition, one or more non-adjacent CH.sub.2 groups may be replaced by O, S, CO, COO, OCO, 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 and/or Cl.

(125) Preferred alkenyl groups are straight-chain alkenyl having 2 to 7 C atoms and cyclohexenyl, in particular ethenyl, propenyl, butenyl, pentenyl, hexenyl, heptenyl, 1,4-cyclohexen-1-yl and 1,4-cyclohexen-3-yl.

(126) The concentration of compounds containing an alkenyl group in the LC host mixture (i.e. without any polymerisable compounds) is preferably from 5% to 100%, very preferably from 20% to 60%.

(127) Especially preferred are LC mixtures containing 1 to 5, preferably 1, 2 or 3 compounds having an alkenyl group.

(128) The mesogenic and LC compounds containing an alkenyl group are preferably selected from the following formulae:

(129) ##STR00023##
in which the individual radicals, on each occurrence identically or differently, each, independently of one another, have the following meaning:

(130) ##STR00024## R.sup.A1 alkenyl having 2 to 9 C atoms or, if at least one of the rings X, Y and Z denotes cyclohexenyl, also one of the meanings of R.sup.A2, R.sup.A2 alkyl having 1 to 12 C atoms, in which, in addition, one or two non-adjacent CH.sub.2 groups may be replaced by O, CHCH, CO, OCO or COO in such a way that O atoms are not linked directly to one another, Z.sup.x CH.sub.2CH.sub.2, CHCH, CF.sub.2O, OCF.sub.2, CH.sub.2O, OCH.sub.2, COO, OCO, C.sub.2F.sub.4, CFCF, CHCHCH.sub.2O, or a single bond, preferably a single bond, L.sup.1-4 each, independently of one another, H, F, Cl, OCF.sub.3, CF.sub.3, CH.sub.3, CH.sub.2F or CHF.sub.2H, preferably H, F or Cl, x 1 or 2, z 0 or 1. R.sup.A2 is preferably straight-chain alkyl or alkoxy having 1 to 8 C atoms or straight-chain alkenyl having 2 to 7 C atoms.

(131) The LC medium preferably comprises no compounds containing a terminal vinyloxy group (OCHCH.sub.2), in particular no compounds of the formula AN or AY in which R.sup.A1 or R.sup.A2 denotes or contains a terminal vinyloxy group (OCHCH.sub.2).

(132) Preferably, L.sup.1 and L.sup.2 denote F, or one of L.sup.1 and L.sup.2 denotes F and the other denotes Cl, and L.sup.3 and L.sup.4 denote F, or one of L.sup.3 and L.sup.4 denotes F and the other denotes Cl.

(133) The compounds of the formula AN are preferably selected from the following sub-formulae:

(134) ##STR00025##
in which alkyl and alkyl* each, independently of one another, denote a straight-chain alkyl radical having 1-6 C atoms, and alkenyl and alkenyl* each, independently of one another, denote a straight-chain alkenyl radical having 2-7 C atoms. Alkenyl and alkenyl* preferably denote CH.sub.2CH, CH.sub.2CHCH.sub.2CH.sub.2, CH.sub.3CHCH, CH.sub.3CH.sub.2CHCH, CH.sub.3(CH.sub.2).sub.2CHCH, CH.sub.3(CH.sub.2).sub.3CHCH or CH.sub.3CHCH(CH.sub.2).sub.2.

(135) The compounds of the formula AY are preferably selected from the following sub-formulae:

(136) ##STR00026## ##STR00027## ##STR00028##
in which alkyl and alkyl* each, independently of one another, denote a straight-chain alkyl radical having 1-6 C atoms, and alkenyl and alkenyl* each, independently of one another, denote a straight-chain alkenyl radical having 2-7 C atoms. Alkenyl and alkenyl* preferably denote CH.sub.2CH, CH.sub.2CHCH.sub.2CH.sub.2, CH.sub.3CHCH, CH.sub.3CH.sub.2CHCH, CH.sub.3(CH.sub.2).sub.2CHCH, CH.sub.3(CH.sub.2).sub.3CHCH or CH.sub.3CHCH(CH.sub.2).sub.2.

(137) Very preferred compounds of the formula AN are selected from the following sub-formulae:

(138) ##STR00029##
in which m denotes 1, 2, 3, 4, 5 or 6, i denotes 0, 1, 2 or 3, and R.sup.b1 denotes H, CH.sub.3 or C.sub.2H.sub.5.

(139) Very particularly preferred compounds of the formula AN are selected from the following sub-formulae:

(140) ##STR00030##

(141) Most preferred are compounds of formula AN1a2 and AN1a5.

(142) Very particularly preferred compounds of the formula AY are selected from the following sub-formulae:

(143) ##STR00031##
in which m and n each, independently of one another, denote 1, 2, 3, 4, 5 or 6, and alkenyl denotes CH.sub.2CH, CH.sub.2CHCH.sub.2CH.sub.2, CH.sub.3CHCH, CH.sub.3CH.sub.2CHCH, CH.sub.3(CH.sub.2).sub.2CHCH, CH.sub.3(CH.sub.2).sub.3CHCH or CH.sub.3CHCH(CH.sub.2).sub.2.

(144) In a first preferred embodiment the LC medium contains an LC component B), or LC host mixture, based on compounds with negative dielectric anisotropy. Such LC media are especially suitable for use in PS-VA and PS-UB-FFS displays. Particularly preferred embodiments of such an LC medium are those of sections a)-z) below: a) LC medium which comprises one or more compounds of the formulae CY and/or PY:

(145) ##STR00032## wherein a denotes 1 or 2, b denotes 0 or 1,

(146) ##STR00033##
denotes

(147) ##STR00034## R.sup.1 and R.sup.2 each, independently of one another, denote alkyl having 1 to 12 C atoms, where, in addition, one or two non-adjacent CH.sub.2 groups may be replaced by O, CHCH, CO, OCO or COO in such a way that O atoms are not linked directly to one another, preferably alkyl or alkoxy having 1 to 6 C atoms, Z.sup.x and Z.sup.y each, independently of one another, denote CH.sub.2CH.sub.2, CHCH, CF.sub.2O, OCF.sub.2, CH.sub.2O, OCH.sub.2, COO, OCO, C.sub.2F.sub.4, CFCF, CHCHCH.sub.2O or a single bond, preferably a single bond, L.sup.1-4 each, independently of one another, denote F, Cl, OCF.sub.3, CF.sub.3, CH.sub.3CH.sub.2F, CHF.sub.2. Preferably, both L.sup.1 and L.sup.2 denote F or one of L.sup.1 and L.sup.2 denotes F and the other denotes Cl, or both L.sup.3 and L.sup.4 denote F or one of L.sup.3 and L.sup.4 denotes F and the other denotes Cl. The compounds of the formula CY are preferably selected from the group consisting of the following sub-formulae:

(148) ##STR00035## ##STR00036## ##STR00037## ##STR00038## in which a denotes 1 or 2, alkyl and alkyl* each, independently of one another, denote a straight-chain alkyl radical having 1-6 C atoms, and alkenyl denotes a straight-chain alkenyl radical having 2-6 C atoms, and (O) denotes an oxygen atom or a single bond. Alkenyl preferably denotes CH.sub.2CH, CH.sub.2CHCH.sub.2CH.sub.2, CH.sub.3CHCH, CH.sub.3CH.sub.2CHCH, CH.sub.3(CH.sub.2).sub.2CHCH, CH.sub.3(CH.sub.2).sub.3CHCH or CH.sub.3CHCH(CH.sub.2).sub.2. The compounds of the formula PY are preferably selected from the group consisting of the following sub-formulae:

(149) ##STR00039## ##STR00040## ##STR00041## in which alkyl and alkyl* each, independently of one another, denote a straight-chain alkyl radical having 1-6 C atoms, and alkenyl denotes a straight-chain alkenyl radical having 2-6 C atoms, and (O) denotes an oxygen atom or a single bond. Alkenyl preferably denotes CH.sub.2CH, CH.sub.2CHCH.sub.2CH.sub.2, CH.sub.3CHCH, CH.sub.3CH.sub.2CHCH, CH.sub.3(CH.sub.2).sub.2CHCH, CH.sub.3(CH.sub.2).sub.3CHCH or CH.sub.3CHCH(CH.sub.2).sub.2. b) LC medium which additionally comprises one or more compounds of the following formula:

(150) ##STR00042## in which the individual radicals have the following meanings:

(151) ##STR00043##
denotes

(152) ##STR00044##
denotes

(153) ##STR00045## R.sup.3 and R.sup.4 each, independently of one another, denote alkyl having 1 to 12 C atoms, in which, in addition, one or two non-adjacent CH.sub.2 groups may be replaced by O, CHCH, CO, OCO or COO in such a way that O atoms are not linked directly to one another, Z.sup.y denotes CH.sub.2CH.sub.2, CHCH, CF.sub.2O, OCF.sub.2, CH.sub.2O, OCH.sub.2, COO, OCO, C.sub.2F.sub.4, CFCF, CHCHCH.sub.2O or a single bond, preferably a single bond. The compounds of the formula ZK are preferably selected from the group consisting of the following sub-formulae:

(154) ##STR00046## in which alkyl and alkyl* each, independently of one another, denote a straight-chain alkyl radical having 1-6 C atoms, and alkenyl denotes a straight-chain alkenyl radical having 2-6 C atoms. Alkenyl preferably denotes CH.sub.2CH, CH.sub.2CHCH.sub.2CH.sub.2, CH.sub.3CHCH, CH.sub.3CH.sub.2CHCH, CH.sub.3(CH.sub.2).sub.2CHCH, CH.sub.3(CH.sub.2).sub.3CHCH or CH.sub.3CHCH(CH.sub.2).sub.2. Especially preferred are compounds of formula ZK1. Particularly preferred compounds of formula ZK are selected from the following sub-formulae:

(155) ##STR00047## wherein the propyl, butyl and pentyl groups are straight-chain groups. Most preferred are compounds of formula ZK1a. c) LC medium which additionally comprises one or more compounds of the following formula:

(156) ##STR00048## in which the individual radicals on each occurrence, identically or differently, have the following meanings: R.sup.5 and R.sup.6 each, independently of one another, denote alkyl having 1 to 12 C atoms, where, in addition, one or two non-adjacent CH.sub.2 groups may be replaced by O, CHCH, CO, OCO or COO in such a way that O atoms are not linked directly to one another, preferably alkyl or alkoxy having 1 to 6 C atoms,

(157) ##STR00049##
denotes

(158) ##STR00050##
denotes

(159) ##STR00051##
and e denotes 1 or 2. The compounds of the formula DK are preferably selected from the group consisting of the following sub-formulae:

(160) ##STR00052## ##STR00053## in which alkyl and alkyl* each, independently of one another, denote a straight-chain alkyl radical having 1-6 C atoms, and alkenyl denotes a straight-chain alkenyl radical having 2-6 C atoms. Alkenyl preferably denotes CH.sub.2CH, CH.sub.2CHCH.sub.2CH.sub.2, CH.sub.3CHCH, CH.sub.3CH.sub.2CHCH, CH.sub.3(CH.sub.2).sub.2CHCH, CH.sub.3(CH.sub.2).sub.3CHCH or CH.sub.3CHCH(CH.sub.2).sub.2. d) LC medium which additionally comprises one or more compounds of the following formula:

(161) ##STR00054## in which the individual radicals have the following meanings:

(162) ##STR00055##
denotes

(163) ##STR00056## with at least one ring F being different from cyclohexylene, f denotes 1 or 2, R.sup.1 and R.sup.2 each, independently of one another, denote alkyl having 1 to 12 C atoms, where, in addition, one or two non-adjacent CH.sub.2 groups may be replaced by O, CHCH, CO, OCO or COO in such a way that O atoms are not linked directly to one another, Z.sup.x denotes CH.sub.2CH.sub.2, CHCH, CF.sub.2O, OCF.sub.2, CH.sub.2O, OCH.sub.2, COO, OCO, C.sub.2F.sub.4, CFCF, CHCHCH.sub.2O or a single bond, preferably a single bond, L.sup.1 and L.sup.2 each, independently of one another, denote F, Cl, OCF.sub.3, CF.sub.3, CH.sub.3, CH.sub.2F, CHF.sub.2. Preferably, both radicals L.sup.1 and L.sup.2 denote F or one of the radicals L.sup.1 and L.sup.2 denotes F and the other denotes Cl. The compounds of the formula LY are preferably selected from the group consisting of the following sub-formulae:

(164) ##STR00057## ##STR00058## ##STR00059## in which R.sup.1 has the meaning indicated above, alkyl denotes a straight-chain alkyl radical having 1-6 C atoms, (O) denotes an oxygen atom or a single bond, and v denotes an integer from 1 to 6. R.sup.1 preferably denotes straight-chain alkyl having 1 to 6 C atoms or straight-chain alkenyl having 2 to 6 C atoms, in particular CH.sub.3, C.sub.2H.sub.5, n-C.sub.3H.sub.7, n-C.sub.4H.sub.9, n-C.sub.5H.sub.11, CH.sub.2CH, CH.sub.2CHCH.sub.2CH.sub.2, CH.sub.3CHCH, CH.sub.3CH.sub.2CHCH, CH.sub.3(CH.sub.2).sub.2CHCH, CH.sub.3(CH.sub.2).sub.3CHCH or CH.sub.3CHCH(CH.sub.2).sub.2. e) LC medium which additionally comprises one or more compounds selected from the group consisting of the following formulae:

(165) ##STR00060## in which alkyl denotes C.sub.1-6-alkyl, L.sup.x denotes H or F, and X denotes F, Cl, OCF.sub.3, OCHF.sub.2 or OCHCF.sub.2. Particular preference is given to compounds of the formula G1 in which X denotes F. f) LC medium which additionally comprises one or more compounds selected from the group consisting of the following formulae:

(166) ##STR00061## ##STR00062## in which R.sup.5 has one of the meanings indicated above for R.sup.1, alkyl denotes C.sub.1-6-alkyl, d denotes 0 or 1, and z and m each, independently of one another, denote an integer from 1 to 6. R.sup.5 in these compounds is particularly preferably C.sub.1-6-alkyl or -alkoxy or C.sub.2-6-alkenyl, d is preferably 1. The LC medium according to the invention preferably comprises one or more compounds of the above-mentioned formulae in amounts of 5% by weight. g) LC medium which additionally comprises one or more biphenyl compounds selected from the group consisting of the following formulae:

(167) ##STR00063## in which alkyl and alkyl* each, independently of one another, denote a straight-chain alkyl radical having 1-6 C atoms, and alkenyl and alkenyl* each, independently of one another, denote a straight-chain alkenyl radical having 2-6 C atoms. Alkenyl and alkenyl* preferably denote CH.sub.2CH, CH.sub.2CHCH.sub.2CH.sub.2, CH.sub.3CHCH, CH.sub.3CH.sub.2CHCH, CH.sub.3(CH.sub.2).sub.2CHCH, CH.sub.3(CH.sub.2).sub.3CHCH or CH.sub.3CHCH(CH.sub.2).sub.2. The proportion of the biphenyls of the formulae B1 to B3 in the LC mixture is preferably at least 3% by weight, in particular 5% by weight. The compounds of the formula B2 are particularly preferred. The compounds of the formulae B1 to B3 are preferably selected from the group consisting of the following sub-formulae:

(168) ##STR00064## in which alkyl* denotes an alkyl radical having 1-6 C atoms. The medium according to the invention particularly preferably comprises one or more compounds of the formulae B1a and/or B2c. h) LC medium which additionally comprises one or more terphenyl compounds of the following formula:

(169) ##STR00065## in which R.sup.5 and R.sup.6 each, independently of one another, have one of the meanings indicated above, and

(170) ##STR00066## each, independently of one another, denote

(171) ##STR00067## in which L.sup.5 denotes F or Cl, preferably F, and L.sup.6 denotes F, Cl, OCF.sub.3, CF.sub.3, CH.sub.3, CH.sub.2F or CHF.sub.2, preferably F. The compounds of the formula T are preferably selected from the group consisting of the following sub-formulae:

(172) ##STR00068## ##STR00069## ##STR00070## in which R denotes a straight-chain alkyl or alkoxy radical having 1-7 C atoms, R* denotes a straight-chain alkenyl radical having 2-7 C atoms, (O) denotes an oxygen atom or a single bond, and m denotes an integer from 1 to 6. R* preferably denotes CH.sub.2CH, CH.sub.2CHCH.sub.2CH.sub.2, CH.sub.3CHCH, CH.sub.3CH.sub.2CHCH, CH.sub.3(CH.sub.2).sub.2CHCH, CH.sub.3(CH.sub.2).sub.3CHCH or CH.sub.3CHCH(CH.sub.2).sub.2. R preferably denotes methyl, ethyl, propyl, butyl, pentyl, hexyl, methoxy, ethoxy, propoxy, butoxy or pentoxy. The LC medium according to the invention preferably comprises the terphenyls of the formula T and the preferred sub-formulae thereof in an amount of 0.5-30% by weight, in particular 1-20% by weight. Particular preference is given to compounds of the formulae T1, T2, T3 and T21. In these compounds, R preferably denotes alkyl, furthermore alkoxy, each having 1-5 C atoms. The terphenyls are preferably employed in mixtures according to the invention if the n value of the mixture is to be 0.1. Preferred mixtures comprise 2-20% by weight of one or more terphenyl compounds of the formula T, preferably selected from the group of compounds T1 to T22. i) LC medium which additionally comprises one or more quaterphenyl compounds selected from the group consisting of the following formulae:

(173) ##STR00071## wherein R.sup.Q is alkyl, alkoxy, oxaalkyl or alkoxyalkyl having 1 to 9 C atoms or alkenyl or alkenyloxy having 2 to 9 C atoms, all of which are optionally fluorinated, X.sup.Q is F, Cl, halogenated alkyl or alkoxy having 1 to 6 C atoms or halogenated alkenyl or alkenyloxy having 2 to 6 C atoms, L.sup.Q1 to L.sup.Q6 independently of each other are H or F, with at least one of L.sup.Q1 to L.sup.Q6 being F. Preferred compounds of formula Q are those wherein R.sup.Q denotes straight-chain alkyl with 2 to 6 C-atoms, very preferably ethyl, n-propyl or n-butyl. Preferred compounds of formula Q are those wherein L.sup.Q3 and L.sup.Q4 are F. Further preferred compounds of formula Q are those wherein L.sup.Q3, L.sup.Q4 and one or two of L.sup.Q1 and L.sup.Q2 are F. Preferred compounds of formula Q are those wherein X.sup.Q denotes F or OCF.sub.3, very preferably F. The compounds of formula Q are preferably selected from the following subformulae

(174) ##STR00072## wherein R.sup.Q has one of the meanings of formula Q or one of its preferred meanings given above and below, and is preferably ethyl, n-propyl or n-butyl. Especially preferred are compounds of formula Q1, in particular those wherein R.sup.Q is n-propyl. Preferably the proportion of compounds of formula Q in the LC medium is from >0 to 5% by weight, very preferably from 0.1 to 2% by weight, most preferably from 0.2 to 1.5% by weight. Preferably the LC medium contains 1 to 5, preferably 1 or 2 compounds of formula Q. The addition of quaterphenyl compounds of formula Q to the LC medium mixture enables to reduce ODF mura, whilst maintaining high UV absorption, enabling quick and complete polymerisation, enabling strong and quick tilt angle generation, and increasing the UV stability of the LC medium. Besides. the addition of compounds of formula Q, which have positive dielectric anisotropy, to the LC medium with negative dielectric anisotropy allows a better control of the values of the dielectric constants .sub. and .sub., and in particular enables to achieve a high value of the dielectric constant .sub. while keeping the dielectric anisotropy constant, thereby reducing the kick-back voltage and reducing image sticking. k) LC medium which additionally comprises one or more compounds selected from the group consisting of the following formulae:

(175) ##STR00073## in which R.sup.1 and R.sup.2 have the meanings indicated above and preferably each, independently of one another, denote straight-chain alkyl having 1 to 6 C atoms or straight-chain alkenyl having 2 to 6 C atoms. Preferred media comprise one or more compounds selected from the formulae O1, O3 and O4. l) LC medium which additionally comprises one or more compounds of the following formula:

(176) ##STR00074## in which

(177) ##STR00075##
denotes

(178) ##STR00076## R.sup.9 denotes H, CH.sub.3, C.sub.2H.sub.5 or n-C.sub.3H.sub.7, (F) denotes an optional fluorine substituent, and q denotes 1, 2 or 3, and R.sup.7 has one of the meanings indicated for R.sup.1, preferably in amounts of >3% by weight, in particular 5% by weight and very particularly preferably 5-30% by weight. Particularly preferred compounds of the formula FI are selected from the group consisting of the following sub-formulae:

(179) ##STR00077## in which R.sup.7 preferably denotes straight-chain alkyl, and R.sup.9 denotes CH.sub.3, C.sub.2H.sub.5 or n-C.sub.3H.sub.7. Particular preference is given to the compounds of the formulae F11, F12 and F13. m) LC medium which additionally comprises one or more compounds selected from the group consisting of the following formulae:

(180) ##STR00078## in which R.sup.8 has the meaning indicated for R.sup.1, and alkyl denotes a straight-chain alkyl radical having 1-6 C atoms. n) LC medium which additionally comprises one or more compounds which contain a tetrahydronaphthyl or naphthyl unit, such as, for example, the compounds selected from the group consisting of the following formulae:

(181) ##STR00079## ##STR00080## in which R.sup.10 and R.sup.11 each, independently of one another, denote alkyl having 1 to 12 C atoms, where, in addition, one or two non-adjacent CH.sub.2 groups may be replaced by O, CHCH, CO, OCO or COO in such a way that O atoms are not linked directly to one another, preferably alkyl or alkoxy having 1 to 6 C atoms, and R.sup.10 and R.sup.11 preferably denote straight-chain alkyl or alkoxy having 1 to 6 C atoms or straight-chain alkenyl having 2 to 6 C atoms, and Z.sup.1 and Z.sup.2 each, independently of one another, denote C.sub.2H.sub.4, CHCH, (CH.sub.2).sub.4, (CH.sub.2).sub.3O, O(CH.sub.2).sub.3, CHCHCH.sub.2CH.sub.2, CH.sub.2CH.sub.2CHCH, CH.sub.2O, OCH.sub.2, COO, OCO, C.sub.2F.sub.4, CFCF, CFCH, CHCF, CH.sub.2 or a single bond. o) LC medium which additionally comprises one or more difluorodibenzo-chromans and/or chromans of the following formulae:

(182) ##STR00081## in which R.sup.11 and R.sup.12 each, independently of one another, have one of the meanings indicated above for R.sup.11, ring M is trans-1,4-cyclohexylene or 1,4-phenylene, Z.sup.m C.sub.2H.sub.4, CH.sub.2O, OCH.sub.2, COO or OCO, c is 0, 1 or 2, preferably in amounts of 3 to 20% by weight, in particular in amounts of 3 to 15% by weight. Particularly preferred compounds of the formulae BC, CR and RC are selected from the group consisting of the following sub-formulae:

(183) ##STR00082## ##STR00083## ##STR00084## in which alkyl and alkyl* each, independently of one another, denote a straight-chain alkyl radical having 1-6 C atoms, (O) denotes an oxygen atom or a single bond, c is 1 or 2, and alkenyl and alkenyl* each, independently of one another, denote a straight-chain alkenyl radical having 2-6 C atoms. Alkenyl and alkenyl* preferably denote CH.sub.2CH, CH.sub.2CHCH.sub.2CH.sub.2, CH.sub.3CHCH, CH.sub.3CH.sub.2CHCH, CH.sub.3(CH.sub.2).sub.2CHCH, CH.sub.3(CH.sub.2).sub.3CHCH or CH.sub.3CHCH(CH.sub.2).sub.2. Very particular preference is given to mixtures comprising one, two or three compounds of the formula BC-2. p) LC medium which additionally comprises one or more fluorinated phenanthrenes and/or dibenzofurans of the following formulae:

(184) ##STR00085## in which R.sup.11 and R.sup.12 each, independently of one another, have one of the meanings indicated above for R.sup.11, b denotes 0 or 1, L denotes F, and r denotes 1, 2 or 3. Particularly preferred compounds of the formulae PH and BF are selected from the group consisting of the following sub-formulae:

(185) ##STR00086## in which R and R each, independently of one another, denote a straight-chain alkyl or alkoxy radical having 1-7 C atoms. q) LC medium which additionally comprises one or more monocyclic compounds of the following formula

(186) ##STR00087## wherein R.sup.1 and R.sup.2 each, independently of one another, denote alkyl having 1 to 12 C atoms, where, in addition, one or two non-adjacent CH.sub.2 groups may be replaced by O, CHCH, CO, OCO or COO in such a way that O atoms are not linked directly to one another, preferably alkyl or alkoxy having 1 to 6 C atoms, L.sup.1 and L.sup.2 each, independently of one another, denote F, Cl, OCF.sub.3, CF.sub.3, CH.sub.3, CH.sub.2F, CHF.sub.2. Preferably, both L.sup.1 and L.sup.2 denote F or one of L.sup.1 and L.sup.2 denotes F and the other denotes Cl, The compounds of the formula Y are preferably selected from the group consisting of the following sub-formulae:

(187) ##STR00088## ##STR00089## in which, Alkyl and Alkyl* each, independently of one another, denote a straight-chain alkyl radical having 1-6 C atoms, Alkoxy denotes a straight-chain alkoxy radical having 1-6 C atoms, Alkenyl and Alkenyl* each, independently of one another, denote a straight-chain alkenyl radical having 2-6 C atoms, and O denotes an oxygen atom or a single bond. Alkenyl and Alkenyl* preferably denote CH.sub.2CH, CH.sub.2CHCH.sub.2CH.sub.2, CH.sub.3CHCH, CH.sub.3CH.sub.2CHCH, CH.sub.3(CH.sub.2).sub.2CHCH, CH.sub.3(CH.sub.2).sub.3CHCH or CH.sub.3CHCH(CH.sub.2).sub.2. Particularly preferred compounds of the formula Y are selected from the group consisting of the following sub-formulae:

(188) ##STR00090## wherein Alkoxy preferably denotes straight-chain alkoxy with 3, 4, or 5 C atoms. r) LC medium which, apart from the polymerisable compounds according to the invention, in particular of the formula I or sub-formulae thereof and the comonomers, comprises no compounds which contain a terminal vinyloxy group (OCHCH.sub.2). s) LC medium which comprises 1 to 5, preferably 1, 2 or 3, polymerisable compounds, preferably selected from polymerisable compounds according to the invention, in particular of the formula I or sub-formulae thereof. t) LC medium in which the proportion of polymerisable compounds, in particular of the formula I or sub-formulae thereof, in the mixture as a whole is 0.05 to 5%, preferably 0.1 to 1%. u) LC medium which comprises 1 to 8, preferably 1 to 5, compounds of the formulae CY1, CY2, PY1 and/or PY2. The proportion of these compounds in the mixture as a whole is preferably 5 to 60%, particularly preferably 10 to 35%. The content of these individual compounds is preferably in each case 2 to 20%. v) LC medium which comprises 1 to 8, preferably 1 to 5, compounds of the formulae CY9, CY10, PY9 and/or PY10. The proportion of these compounds in the mixture as a whole is preferably 5 to 60%, particularly preferably 10 to 35%. The content of these individual compounds is preferably in each case 2 to 20%. w) LC medium which comprises 1 to 10, preferably 1 to 8, compounds of the formula ZK, in particular compounds of the formulae ZK1, ZK2 and/or ZK6. The proportion of these compounds in the mixture as a whole is preferably 3 to 25%, particularly preferably 5 to 45%. The content of these individual compounds is preferably in each case 2 to 20%. x) LC medium in which the proportion of compounds of the formulae CY, PY and ZK in the mixture as a whole is greater than 70%, preferably greater than 80%. y) LC medium in which the LC host mixture contains one or more compounds containing an alkenyl group, preferably selected from the group consisting of formula CY, PY and LY, wherein one or both of R.sup.1 and R.sup.2 denote straight-chain alkenyl having 2-6 C atoms, formula ZK and DK, wherein one or both of R.sup.3 and R.sup.4 or one or both of R.sup.5 and R.sup.6 denote straight-chain alkenyl having 2-6 C atoms, and formula B2 and B3, very preferably selected from formulae CY15, CY16, CY24, CY32, PY15, PY16, ZK3, ZK4, DK3, DK6, B2 and B3, most preferably selected from formulae ZK3, ZK4, B2 and B3. The concentration of these compounds in the LC host mixture is preferably from 2 to 70%, very preferably from 3 to 55%. z) LC medium which contains one or more, preferably 1 to 5, compounds selected of formula PY1-PY8, very preferably of formula PY2. The proportion of these compounds in the mixture as a whole is preferably 1 to 30%, particularly preferably 2 to 20%. The content of these individual compounds is preferably in each case 1 to 20%. z1) LC medium which contains one or more, preferably 1, 2 or 3, compounds of formula T2. The content of these compounds in the mixture as a whole is preferably 1 to 20%. z2) LC medium in which the LC host mixture contains one or more, preferably 1, 2 or 3, compounds of formula BF1, and one or more, preferably 1, 2 or 3, compounds selected from formulae AY14, AY15 and AY16, very preferably of formula AY14. The proportion of the compounds of formula AY14-AY16 in the LC host mixture is preferably from 2 to 35%, very preferably from 3 to 30%. The proportion of the compounds of formula BF1 in the LC host mixture is preferably from 0.5 to 20%, very preferably from 1 to 15%. Further preferably the LC host mixture according to this preferred embodiment contains one or more, preferably 1, 2 or 3 compounds of formula T, preferably selected from formula T1, T2 and T5, very preferably from formula T2 or T5. The proportion of the compounds of formula T in the LC host mixture medium is preferably from 0.5 to 15%, very preferably from 1 to 10%.

(189) In a second preferred embodiment the LC medium contains an LC host mixture based on compounds with positive dielectric anisotropy. Such LC media are especially suitable for use in PS-OCB-, PS-TN-, PS-Posi-VA-, PS-IPS- or PS-FFS-displays.

(190) Particularly preferred is an LC medium of this second preferred embodiment, which contains one or more compounds selected from the group consisting of compounds of formula AA and BB

(191) ##STR00091##
and optionally contains, in addition to the compounds of formula AA and/or BB, one or more compounds of formula CC

(192) ##STR00092##
in which the individual radicals have the following meanings:

(193) ##STR00093##
each, independently of one another, and on each occurrence, identically or differently

(194) ##STR00094##
each, independently of one another, and on each occurrence, identically or differently

(195) ##STR00095## R.sup.21, R.sup.31, R.sup.41, R.sup.42 each, independently of one another, alkyl, alkoxy, oxaalkyl or alkoxyalkyl having 1 to 9 C atoms or alkenyl or alkenyloxy having 2 to 9 C atoms, all of which are optionally fluorinated, X.sup.0 F, Cl, halogenated alkyl or alkoxy having 1 to 6 C atoms or halogenated alkenyl or alkenyloxy having 2 to 6 C atoms, Z.sup.31 CH.sub.2CH.sub.2, CF.sub.2CF.sub.2, COO, trans-CHCH, trans-CFCF, CH.sub.2O or a single bond, preferably CH.sub.2CH.sub.2, COO, trans-CHCH or a single bond, particularly preferably COO, trans-CHCH or a single bond, Z.sup.41, Z.sup.42 CH.sub.2CH.sub.2, COO, trans-CHCH, trans-CFCF, CH.sub.2O, CF.sub.2O, CC or a single bond, preferably a single bond, L.sup.21, L.sup.22, L.sup.31, L.sup.32 H or F, g 0, 1, 2 or 3, h 0, 1, 2 or 3.
X.sup.0 is preferably F, Cl, CF.sub.3, CHF.sub.2, OCF.sub.3, OCHF.sub.2, OCFHCF.sub.3, OCFHCHF.sub.2, OCFHCHF.sub.2, OCF.sub.2CH.sub.3, OCF.sub.2CHF.sub.2, OCF.sub.2CHF.sub.2, OCF.sub.2CF.sub.2CHF.sub.2, OCF.sub.2CF.sub.2CHF.sub.2, OCFHCF.sub.2CF.sub.3, OCFHCF.sub.2CHF.sub.2, OCF.sub.2CF.sub.2CF.sub.3, OCF.sub.2CF.sub.2CClF.sub.2, OCClFCF.sub.2CF.sub.3 or CHCF.sub.2, very preferably F or OCF.sub.3

(196) The compounds of formula AA are preferably selected from the group consisting of the following formulae:

(197) ##STR00096##
in which A.sup.21, R.sup.21, X.sup.0, L.sup.21 and L.sup.22 have the meanings given in formula AA, L.sup.23 and L.sup.24 each, independently of one another, are H or F, and X.sup.0 is preferably F. Particularly preferred are compounds of formulae AA1 and AA2.

(198) Particularly preferred compounds of formula AA1 are selected from the group consisting of the following subformulae:

(199) ##STR00097##
in which R.sup.21, X.sup.0, L.sup.21 and L.sup.22 have the meaning given in formula AA1, L.sup.23, L.sup.24, L.sup.25 and L.sup.26 are each, independently of one another, H or F, and X.sup.0 is preferably F.

(200) Very particularly preferred compounds of formula AA1 are selected from the group consisting of the following subformulae:

(201) ##STR00098##
In which R.sup.21 is as defined in formula AA1.

(202) Very preferred compounds of formula AA2 are selected from the group consisting of the following subformulae:

(203) ##STR00099## ##STR00100##
in which R.sup.21, X.sup.0, L.sup.21 and L.sup.22 have the meaning given in formula AA2, L.sup.23, L.sup.24, L.sup.25 and L.sup.26 each, independently of one another, are H or F, and X.sup.0 is preferably F.

(204) Very particularly preferred compounds of formula AA2 are selected from the group consisting of the following subformulae:

(205) ##STR00101## ##STR00102##
in which R.sup.21 and X.sup.0 are as defined in formula AA2.

(206) Particularly preferred compounds of formula AA3 are selected from the group consisting of the following subformulae:

(207) ##STR00103##
in which R.sup.21, X.sup.0, L.sup.21 and L.sup.22 have the meaning given in formula AA3, and X.sup.0 is preferably F.

(208) Particularly preferred compounds of formula AA4 are selected from the group consisting of the following subformulae:

(209) ##STR00104##
in which R.sup.21 is as defined in formula AA4.

(210) The compounds of formula BB are preferably selected from the group consisting of the following formulae:

(211) ##STR00105##
in which g, A.sup.31, A.sup.32, R.sup.31, X.sup.0, L.sup.31 and L.sup.32 have the meanings given in formula BB, and X.sup.0 is preferably F. Particularly preferred are compounds of formulae BB1 and BB2.

(212) Particularly preferred compounds of formula BB1 are selected from the group consisting of the following subformulae:

(213) ##STR00106##
in which R.sup.31, X.sup.0, L.sup.31 and L.sup.32 have the meaning given in formula BB1, and X.sup.0 is preferably F.

(214) Very particularly preferred compounds of formula BB1a are selected from the group consisting of the following subformulae:

(215) ##STR00107##
in which R.sup.31 is as defined in formula BB1.

(216) Very particularly preferred compounds of formula BB1b are selected from the group consisting of the following subformulae:

(217) ##STR00108##
in which R.sup.31 is as defined in formula BB1.

(218) Particularly preferred compounds of formula BB2 are selected from the group consisting of the following subformulae:

(219) ##STR00109## ##STR00110##
in which R.sup.31, X.sup.0, L.sup.31 and L.sup.32 have the meaning given in formula BB2, L.sup.00, L.sup.34, L.sup.35 and L.sup.36 are each, independently of one another, H or F, and X.sup.0 is preferably F.

(220) Very particularly preferred compounds of formula BB2 are selected from the group consisting of the following subformulae:

(221) ##STR00111##
in which R.sup.31 is as defined in formula BB2.

(222) Very particularly preferred compounds of formula BB2b are selected from the group consisting of the following subformulae

(223) ##STR00112##
in which R.sup.31 is as defined in formula BB2.

(224) Very particularly preferred compounds of formula BB2c are selected from the group consisting of the following subformulae:

(225) ##STR00113##
in which R.sup.31 is as defined in formula BB2.

(226) Very particularly preferred compounds of formula BB2d and BB2e are selected from the group consisting of the following subformulae:

(227) ##STR00114##
in which R.sup.31 is as defined in formula BB2.

(228) Very particularly preferred compounds of formula BB2f are selected from the group consisting of the following subformulae:

(229) ##STR00115##
in which R.sup.31 is as defined in formula BB2.

(230) Very particularly preferred compounds of formula BB2g are selected from the group consisting of the following subformulae:

(231) ##STR00116##
in which R.sup.31 is as defined in formula BB2.

(232) Very particularly preferred compounds of formula BB2h are selected from the group consisting of the following subformulae:

(233) ##STR00117##
in which R.sup.31 and X.sup.0 are as defined in formula BB2.

(234) Very particularly preferred compounds of formula BB2i are selected from the group consisting of the following subformulae:

(235) ##STR00118##
in which R.sup.31 and X.sup.0 are as defined in formula BB2.

(236) Very particularly preferred compounds of formula BB2k are selected from the group consisting of the following subformulae:

(237) ##STR00119##
in which R.sup.31 and X.sup.0 are as defined in formula BB2.

(238) Alternatively to, or in addition to, the compounds of formula BB1 and/or BB2 the LC media may also comprise one or more compounds of formula BB3 as defined above.

(239) Particularly preferred compounds of formula BB3 are selected from the group consisting of the following subformulae:

(240) ##STR00120##
in which R.sup.31 is as defined in formula BB3.

(241) Preferably the LC media according to this second preferred embodiment comprise, in addition to the compounds of formula AA and/or BB, one or more dielectrically neutral compounds having a dielectric anisotropy in the range from 1.5 to +3, preferably selected from the group of compounds of formula CC as defined above.

(242) Particularly preferred compounds of formula CC are selected from the group consisting of the following subformulae:

(243) ##STR00121## ##STR00122##

(244) In which R.sup.41 and R.sup.42 have the meanings given in formula CC, and preferably denote each, independently of one another, alkyl, alkoxy, fluorinated alkyl or fluorinated alkoxy with 1 to 7 C atoms, or alkenyl, alkenyloxy, alkoxyalkyl or fluorinated alkenyl with 2 to 7 C atoms, and L.sup.4 is H or F.

(245) Preferably the LC media according to this second preferred embodiment comprise, in addition or alternatively to the dielectrically neutral compounds of formula CC, one or more dielectrically neutral compounds having a dielectric anisotropy in the range from 1.5 to +3, selected from the group of compounds of formula DD.

(246) ##STR00123##

(247) In which A.sup.41, A.sup.42, Z.sup.41, Z.sup.42, R.sup.41, R.sup.42 and h have the meanings given in formula CC.

(248) Particularly preferred compounds of formula DD are selected from the group consisting of the following subformulae:

(249) ##STR00124##
in which R.sup.41 and R.sup.42 have the meanings given in formula DD and R.sup.41 preferably denotes alkyl bedeutet, and in formula DD1 R.sup.42 preferably denotes alkenyl, particularly preferably (CH.sub.2).sub.2CHCHCH.sub.3, and in formula DD2 R.sup.42 preferably denotes alkyl, (CH.sub.2).sub.2CHCH.sub.2 or (CH.sub.2).sub.2CHCHCH.sub.3.

(250) The compounds of formula AA and BB are preferably used in the LC medium according to the invention in a concentration from 2% to 60%, more preferably from 3% to 35%, and very particularly preferably from 4% to 30% in the mixture as a whole.

(251) The compounds of formula CC and DD are preferably used in the LC medium according to the invention in a concentration from 2% to 70%, more preferably from 5% to 65%, even more preferably from 10% to 60%, and very particularly preferably from 10%, preferably 15%, to 55% in the mixture as a whole.

(252) The combination of compounds of the preferred embodiments mentioned above with the polymerised compounds described above causes low threshold voltages, low rotational viscosities and very good low-temperature stabilities in the LC media according to the invention at the same time as constantly high clearing points and high HR values, and allows the rapid establishment of a particularly low pretilt angle in PSA displays. In particular, the LC media exhibit significantly shortened response times, in particular also the grey-shade response times, in PSA displays compared with the media from the prior art.

(253) The LC media and LC host mixtures of the present invention preferably have a nematic phase range of at least 80 K, particularly preferably at least 100 K, and a rotational viscosity 250 mPa.Math.s, preferably 200 mPa.Math.s, at 20 C.

(254) In the VA-type displays according to the invention, the molecules in the layer of the LC medium in the switched-off state are aligned perpendicular to the electrode surfaces (homeotropically) or have a tilted homeotropic alignment. On application of an electrical voltage to the electrodes, a realignment of the LC molecules takes place with the longitudinal molecular axes parallel to the electrode surfaces.

(255) LC media according to the invention based on compounds with negative dielectric anisotropy according to the first preferred embodiment, in particular for use in displays of the PS-VA and PS-UB-FFS type, have a negative dielectric anisotropy , preferably from 0.5 to 10, in particular from 2.5 to 7.5, at 20 C. and 1 kHz.

(256) The birefringence n in LC media according to the invention for use in displays of the PS-VA and PS-UB-FFS type is preferably below 0.16, particularly preferably from 0.06 to 0.14, very particularly preferably from 0.07 to 0.12.

(257) In the OCB-type displays according to the invention, the molecules in the layer of the LC medium have a bend alignment. On application of an electrical voltage, a realignment of the LC molecules takes place with the longitudinal molecular axes perpendicular to the electrode surfaces.

(258) LC media according to the invention for use in displays of the PS-OCB, PS-TN, PS-IPS, PS-posi-VA and PS-FFS type are preferably those based on compounds with positive dielectric anisotropy according to the second preferred embodiment, and preferably have a positive dielectric anisotropy from +4 to +17 at 20 C. and 1 kHz.

(259) The birefringence n in LC media according to the invention for use in displays of the PS-OCB type is preferably from 0.14 to 0.22, particularly preferably from 0.16 to 0.22.

(260) The birefringence n in LC media according to the invention for use in displays of the PS-TN-, PS-posi-VA-, PS-IPS-oder PS-FFS-type is preferably from 0.07 to 0.15, particularly preferably from 0.08 to 0.13.

(261) LC media according to the invention, based on compounds with positive dielectric anisotropy according to the second preferred embodiment, for use in displays of the PS-TN-, PS-posi-VA-, PS-IPS-oder PS-FFS-type, preferably have a positive dielectric anisotropy from +2 to +30, particularly preferably from +3 to +20, at 20 C. and 1 kHz.

(262) The LC media according to the invention may also comprise further additives which are known to the person skilled in the art and are described in the literature, such as, for example, polymerisation initiators, inhibitors, stabilisers, surface-active substances or chiral dopants. These may be polymerisable or non-polymerisable. Polymerisable additives are accordingly ascribed to the polymerisable component or component A). Non-polymerisable additives are accordingly ascribed to the non-polymerisable component or component B).

(263) In a preferred embodiment the LC media contain one or more chiral dopants, preferably in a concentration from 0.01 to 1%, very preferably from 0.05 to 0.5%. The chiral dopants are preferably selected from the group consisting of compounds from Table B below, very preferably from the group consisting of R- or S-1011, R- or S-2011, R- or S-3011, R- or S-4011, and R- or S-5011.

(264) In another preferred embodiment the LC media contain a racemate of one or more chiral dopants, which are preferably selected from the chiral dopants mentioned in the previous paragraph.

(265) Furthermore, it is possible to add to the LC media, for example, 0 to 15% by weight of pleochroic dyes, furthermore nanoparticles, conductive salts, preferably ethyldimethyldodecylammonium 4-hexoxybenzoate, tetrabutyl-ammonium tetraphenylborate or complex salts of crown ethers (cf., for example, Haller et al., Mol. Cryst. Liq. Cryst. 24, 249-258 (1973)), for improving the conductivity, or substances for modifying the dielectric anisotropy, the viscosity and/or the alignment of the nematic phases. Substances of this type are described, for example, in DE-A 22 09 127, 22 40 864, 23 21 632, 23 38 281, 24 50 088, 26 37 430 and 28 53 728.

(266) The individual components of the preferred embodiments a)-z) of the LC media according to the invention are either known or methods for the preparation thereof can readily be derived from the prior art by the person skilled in the relevant art, since they are based on standard methods described in the literature. Corresponding compounds of the formula CY are described, for example, in EP-A-0 364 538. Corresponding compounds of the formula ZK are described, for example, in DE-A-26 36 684 and DE-A-33 21 373.

(267) The LC media which can be used in accordance with the invention are prepared in a manner conventional per se, for example by mixing one or more of the above-mentioned compounds with one or more polymerisable compounds as defined above, and optionally with further liquid-crystalline compounds and/or additives. In general, the desired amount of the components used in lesser amount is dissolved in the components making up the principal constituent, advantageously at elevated temperature. It is also possible to mix solutions of the components in an organic solvent, for example in acetone, chloroform or methanol, and to remove the solvent again, for example by distillation, after thorough mixing. The invention furthermore relates to the process for the preparation of the LC media according to the invention.

(268) It goes without saying to the person skilled in the art that the LC media according to the invention may also comprise compounds in which, for example, H, N, O, Cl, F have been replaced by the corresponding isotopes like deuterium etc.

(269) The following examples explain the present invention without restricting it. However, they show the person skilled in the art preferred mixture concepts with compounds preferably to be employed and the respective concentrations thereof and combinations thereof with one another. In addition, the examples illustrate which properties and property combinations are accessible.

(270) The following abbreviations are used:

(271) (n, m, z: in each case, independently of one another, 1, 2, 3, 4, 5 or 6)

(272) TABLE-US-00001 TABLE A 0 0 0 0 0 0 0

(273) In a preferred embodiment of the present invention, the LC media according to the invention comprise one or more compounds selected from the group consisting of compounds from Table A.

(274) TABLE-US-00002 TABLE B C 15 00 CB 15 01 CM 21 02 R/S-811 03 CM 44 04 CM 45 05 CM 47 06 CN 07 R/S-2011 08 R/S-3011 09 R/S-4011 0 R/S-5011 R/S-1011

(275) Table B shows possible chiral dopants which can be added to the LC media according to the invention.

(276) The LC media preferably comprise 0 to 10% by weight, in particular 0.01 to 5% by weight, particularly preferably 0.1 to 3% by weight, of dopants. The LC media preferably comprise one or more dopants selected from the group consisting of compounds from Table B.

(277) TABLE-US-00003 TABLE C 0 0 0 0

(278) Table C shows possible stabilisers which can be added to the LC media according to the invention.

(279) (n here denotes an integer from 1 to 12, preferably 1, 2, 3, 4, 5, 6, 7 or 8, terminal methyl groups are not shown).

(280) O. denotes an oxygen free radical.

(281) The LC media preferably comprise 0 to 10% by weight, in particular 1 ppm to 5% by weight, particularly preferably 1 ppm to 1% by weight, of stabilisers. The LC media preferably comprise one or more stabilisers selected from the group consisting of compounds from Table C.

(282) TABLE-US-00004 TABLE D RM-1 RM-2 RM-3 RM-4 RM-5 RM-6 RM-7 RM-8 RM-9 0 RM-10 RM-11 RM-12 RM-13 RM-14 RM-15 RM-16 RM-17 RM-18 RM-19 0 RM-20 RM-21 RM-22 RM-23 RM-24 RM-25 RM-26 RM-27 RM-28 RM-29 0 RM-30 RM-31 RM-32 RM-33 RM-34 RM-35 RM-36 RM-37 RM-38 RM-39 0 RM-40 RM-41 RM-42 RM-43 RM-44 RM-45 RM-46 RM-47 RM-48 RM-49 00 RM-50 01 RM-51 02 RM-52 03 RM-53 04 RM-54 05 RM-55 06 RM-56 07 RM-57 08 RM-58 09 RM-59 0 RM-60 RM-61 RM-62 RM-63 RM-64 RM-65 RM-66 RM-67 RM-68 RM-69 0 RM-70 RM-71

(283) Table D shows illustrative compounds which can be used in the LC media in accordance with the present invention, preferably as reactive mesogenic compounds.

(284) In a preferred embodiment of the present invention, the mesogenic media comprise one or more compounds selected from the group of the compounds from Table D.

(285) In addition, the following abbreviations and symbols are used: V.sub.0 threshold voltage, capacitive [V] at 20 C., n.sub.e extraordinary refractive index at 20 C. and 589 nm, n.sub.o ordinary refractive index at 20 C. and 589 nm, n optical anisotropy at 20 C. and 589 nm, .sub. dielectric permittivity perpendicular to the director at 20 C. and 1 kHz, .sub. dielectric permittivity parallel to the director at 20 C. and 1 kHz, dielectric anisotropy at 20 C. and 1 kHz, cl.p., T(N,I) clearing point [ C.], .sub.1 rotational viscosity at 20 C. [mPa.Math.s], K.sub.1 elastic constant, splay deformation at 20 C. [pN], K.sub.2 elastic constant, twist deformation at 20 C. [pN], K.sub.3 elastic constant, bend deformation at 20 C. [pN].

(286) Unless explicitly noted otherwise, all concentrations in the present application are quoted in percent by weight and relate to the corresponding mixture as a whole, comprising all solid or liquid-crystalline components, without solvents.

(287) Unless explicitly noted otherwise, all temperature values indicated in the present application, such as, for example, for the melting point T(C,N), the transition from the smectic (S) to the nematic (N) phase T(S,N) and the clearing point T(N,I), are quoted in degrees Celsius ( C.). M.p. denotes melting point, cl.p.=clearing point. Furthermore, C=crystalline state, N=nematic phase, S=smectic phase and I=isotropic phase. The data between these symbols represent the transition temperatures.

(288) All physical properties are and have been determined in accordance with Merck Liquid Crystals, Physical Properties of Liquid Crystals, Status November 1997, Merck KGaA, Germany, and apply for a temperature of 20 C., and n is determined at 589 nm and at 1 kHz, unless explicitly indicated otherwise in each case.

(289) The term threshold voltage for the present invention relates to the capacitive threshold (V.sub.0), also known as the Freedericks threshold, unless explicitly indicated otherwise. In the examples, the optical threshold may also, as generally usual, be quoted for 10% relative contrast (V.sub.10).

(290) Unless stated otherwise, the process of polymerising the polymerisable compounds in the PSA displays as described above and below is carried out at a temperature where the LC medium exhibits a liquid crystal phase, preferably a nematic phase, and most preferably is carried out at room temperature.

(291) Unless stated otherwise, methods of preparing test cells and measuring their electrooptical and other properties are carried out by the methods as described hereinafter or in analogy thereto.

(292) The display used for measurement of the capacitive threshold voltage consists of two plane-parallel glass outer plates at a separation of 25 m, each of which has on the inside an electrode layer and an unrubbed polyimide alignment layer on top, which effect a homeotropic edge alignment of the liquid-crystal molecules.

(293) The display or test cell used for measurement of the tilt angles consists of two plane-parallel glass outer plates at a separation of 4 m, each of which has on the inside an electrode layer and a polyimide alignment layer on top, where the two polyimide layers are rubbed antiparallel to one another and effect a homeotropic edge alignment of the liquid-crystal molecules.

(294) The polymerisable compounds are polymerised in the display or test cell by irradiation with UVA light of defined intensity for a prespecified time, with a voltage simultaneously being applied to the display (usually 10 V to 30 V alternating current, 1 kHz). In the examples, unless indicated otherwise, a metal halide lamp and an intensity of 100 mW/cm.sup.2 is used for polymerisation. The intensity is measured using a standard UVA meter (Hoenle UV-meter high end with UVA sensor).

(295) The tilt angle is determined by crystal rotation experiment (Autronic-Melchers TBA-105). A low value (i.e. a large deviation from the 90 angle) corresponds to a large tilt here.

(296) The VHR value is measured as follows: 0.3% of a polymerisable monomeric compound is added to the LC host mixture, and the resultant mixture is introduced into VA-VHR test cells which comprise an unrubbed VA-polyimide alignment layer. The LC-layer thickness d is approx. 6 m, unless stated otherwise. The VHR value is determined after 5 min at 100 C. before and after UV exposure at 1 V, 60 Hz, 64 s pulse (measuring instrument: Autronic-Melchers VHRM-105).

(297) 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.

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

(299) The entire disclosures of all applications, patents and publications, cited herein and of corresponding application No. EP 14002646.9 filed Jul. 30, 2014, is incorporated by reference herein.

Example 1

(300) Polymerisable monomeric compound 1 is prepared as follows.

(301) ##STR00322##

(302) 1a: To a solution of 4-bromoresorcinol (15.00 g, 79.4 mmol) and ethylenecarbonate (19.57 g. 222.2 mmol) in DMF (80 ml) is added dry potassium carbonate (4.39 g, 31.7 mmol). The reaction mixture is refluxed overnight. After cooling to room temperature, the reaction mixture is added into 100 ml water and neutralized carefully with 2 M HCl. The aqueous phase is extracted with ethylacetate. The organic phase is combined and washed with sat. aq. NaCl solution, dried over sodium sulfate. After removing solvent in vacuo, the solid residue is recrystallized with heptane/ethyl acetate 4:1 to provide 1a as white solid (9.1 g).

(303) 1b: To a solution of 1a (15.60 g, 56.3 mol) and 4-benzyloxylphenyl boronic acid (15.4 g, 67.5 mmol) in 350 ml 1,4-dioxane was added 73.9 g (320.8 mmol) potassium phosphate. The resulted suspension is degassed carefully with argon. Tris(dibenzylidene acetone)dipalladium(0) (1.55 g, 1.7 mmol) and 2-dicyclohexylphosphine-2,6-dimethoxylbiphenyl (SPhos) (2.38 g, 5.6 mmol) is then added. The reaction mixture is heated to reflux and stirred overnight. After cooling to room temperature 400 ml dist. water and 150 ml ethylacetate and 150 ml THF is added, and the mixture is neutralized carefully with 6 M HCl acid under cooling to pH4. The aqueous phase is extracted with ethylacetate. The organic phase is combined and washed with sat. aq. NaCl solution, dried over sodium sulfate. After removing solvent in vacuo, the solid residue is purified by column chromatography with THF/toluene 3:2 as eluent to provide 1b as white solid (16.8 g).

(304) 1c: A solution of 1b (16.7 g, 43.9 mmol) in tetrahydrofuran (160 ml) is treated with palladium (5%) on activated charcoal (2.0 g) and submitted to hydrogenation for 19 hs. The catalyst is then filtered off, and the remaining solution is concentrated in vacuo. The residue is recrystallized from toluene/ethylacetate solvent mixture to 1c as white solid (12.5 g).

(305) 1: Methacrylic acid (18.42 g, 214.0 mmol) and 4-(dimethylamino)pyridine (0.5 g, 4.1 mmol) is added to a suspension of 1c (12.5 g, 42.8 mmol) in dichloromethane (180 ml). The reaction mixture is treated dropwise at 0 C. with a solution of N-(3-dimethylaminopropyl)-N-ethylcarbodiimide (34.50 g, 222.5 mmol) in dichloromethane (20 ml) and stirred for 20 h at room temperature. After removing solvent in vacuo, the oily residue is purified by silica gel chromatography with heptane/ethyl acetate 7:3 as eluent. The obtained product is recrystallized from ethanol to afford white crystals of 1 (10.1 g, mp. 42 C.).

Example 2

(306) Polymerisable monomeric compound 2 is prepared from the commercially available 3-fluoro-4-benzyloxylphenyl boronic acid in analogy to Example 1 as follows.

(307) ##STR00323##

Example 3

(308) Polymerisable monomeric compound 3 is prepared as follows.

(309) ##STR00324##

(310) 3a: To a solution of 2-bromo-4-iodio-phenol (75.00 g, 238.4 mmol) in 460 ml ethyl methylketone is added potassium carbonate (39.50 g. 286.0 mmol) in several portions. The reaction mixture is heated to reflux, to which benzylbromide (34.0 ml, 286.0 mmol) is added dropwise, and stirred overnight while refluxing. After cooling to room temperature, the reaction mixture is filtrated. The solid residue is washed thoroughly with aceton. After removing solvent in vacuo, the oily residue is purified by silica gel chromatography with heptane/toluene 7:3 as eluent. The crude product is further recrystallized from heptane to provide 3a as white solid (85.7 g).

(311) 3b: To a solution of 3a (85.50 g, 220.0 mmol) and 4-benzyloxylphenyl boronic acid (49.11 g, 215.3 mmol) in 1000 ml toluene was added 500 ml dist. water and 250 ml ethanol. Potassium carbonate (64.06 g, 604.4 mmol) is added. The resulted suspension is degassed carefully with argon. Tetrakis(triphenylphosphine)palladium(0) (9.11 g, 7.89 mmol) is then added. The reaction mixture is heated to reflux and stirred overnight. After cooling to room temperature, the reaction mixture is neutralized carefully with 6 M HCl acid under cooling to pH7. The aqueous phase is extracted with ethylacetate. The organic phase is combined and washed with sat. aq. NaCl solution, dried over sodium sulfate. After removing solvent in vacuo, the solid residue is purified by column chromatography with THF/toluene 9:1 as eluent. The crude product is further recrystallized from toluene to provide 3b as grayish solid (76.3 g).

(312) 3c: To a solution of 3b (45.00 g, 99.0 mmol) and 4-benzyloxylphenyl boronic acid (15.81 g, 108.9 mmol) in 340 ml 1,4-dioxane was added 80 ml dist. water. Potassium carbonate (21.00 g, 198.0 mmol) is added. The resulted suspension is degassed carefully with argon. Bis(triphenylphosphine)palladium(II) dichloride (2.18 g, 2.97 mmol) is then added. The reaction mixture is heated to reflux and stirred overnight. After cooling to room temperature, the reaction mixture is neutralized carefully with 2 M HCl acid under cooling to pH7. The aqueous phase is extracted with methyl t-butyl ether. The organic phase is combined and washed with sat. aq. NaCl solution, dried over sodium sulfate. After removing solvent in vacuo, the solid residue is recrystallized from isopropanol to provide 3c as white solid (41.3 g).

(313) 3d: A suspension of 3c (10.0 g, 21.8 mmol) in tetrahydrofuran (150 ml) is treated with palladium (5%) on activated charcoal (10.0 g) and submitted to hydrogenation for 30 hs. The catalyst is then filtered off. After removing solvent in vacuo, 3d is obtained as solid (6.3 g).

(314) 3: Methacrylic acid (9.39 g, 67.0 mmol) and 4-(dimethylamino)pyridine (0.23 g, 1.9 mmol) is added to a suspension of 3d (5.50 g, 19.1 mmol) in dichloromethane (200 ml). The reaction mixture is treated dropwise at 0 C. with a solution of N-(3-dimethylaminopropyl)-N-ethylcarbodiimide (16.9 g, 109.0 mmol) in dichloromethane (60 ml) and stirred for 20 hs at room temperature. The reaction mixture is concentrated in vacuo, and the oily residue is purified by column chromatography on silica gel with chlorobutane/ethyl acetate 9:1 as eluent. The obtained product is recrystallized from ethanol to afford white crystals of 3 (2.7 g, mp. 105 C.).

Example 4

(315) Polymerisable monomeric compound 4 is prepared as follows.

(316) ##STR00325##

(317) 4a: To a solution of 4-bromo-isophthalic acid (21.00 g, 85.7 mmol) in DMF (200 ml) is added potassium carbonate (27.24 g, 197.1 mmol). To the resulted suspension (2-bromo-ethoxymethyl)-benzene (40.00 g, 186.00 mmol) is added. The reaction mixture is stirred at 70 C. for 4 hours. After cooling to room temperature, the reaction mixture is added into 1000 ml water and extracted with 3300 ml methyl-t-butyl ether (MTBE). The organic phase is washed with sat. aq. NaCl solution, dried over sodium sulfate. After removing solvent in vacuo, the oily residue is purified by column chromatography on silica gel with heptane/ethyl acetate 3:2 as eluent to provide 4a as colorless oil (36.1 g).

(318) 4b: To a solution of sodium metaborate tetrahydrate (5.86 g, 42.1 mmol) in dist. water (20 ml) is added the solution of 4a (6.00 g, 26.3 mmol) and 4-(benzyloxy)phenyl boronic acid (12.00 g, 23.4 mmol) in 70 ml THF. After thoroughly degassing with argon, bis(triphenylphosphine)-palladium(II) chloride (1.24 g, 1.7 mmol) is added, followed by the addition of hydrazinium hydroxide (0.05 ml, 1 mmol). The reaction mixture is heated to reflux and stirred for 5 hours. After cooling to room temperature, the reaction mixture is carefully neutralized with 2 M HCl acid. The aqueous phase is separated and extracted with ethyl acetate. The organic phase is combined and dried over anhydrous sodium sulfate. After removing organic solvent, the oily residue is purified by column chromatography on silica gel with toluene/ethyl acetate 9:1 as eluent to afford 4b as brownish oil (13.2 g).

(319) 4c: A suspension of 4b (13.0 g, 20.4 mmol) in tetrahydrofuran (130 ml) is treated with palladium (5%) on activated charcoal (10.0 g) and submitted to hydrogenation for 30 hs. The catalyst is then filtered off. After removing solvent in vacuo, the solid residue is purified by column chromatography on silica gel with toluene/ethyl acetate 5:1 as elute to provide 4c as white solid (5.6 g).

(320) 4: Methacrylic acid (6.96 g, 80.8 mmol) and 4-(dimethylamino)pyridine (0.20 g, 1.6 mmol) is added to a suspension of 4c (5.60 g, 16.2 mmol) in dichloromethane (60 ml). The reaction mixture is treated dropwise at 0 C. with a solution of N-(3-dimethylaminopropyl)-N-ethylcarbodiimide (12.9 g, 83.2 mmol) in dichloromethane (20 ml) and stirred for 20 hs at room temperature. The reaction mixture is concentrated in vacuo, and the oily residue is purified by column chromatography on silica gel with dichloromethane as eluent. The obtained product is recrystallized from ethanol to afford white crystals of 4 (3.0 g, mp. 54 C.).

Example 5

(321) Polymerisable monomeric compound 5 is prepared from the commercially available 4-bromo-3-hydroxyl benzoic acid in analogy to Example 4 as follows.

(322) ##STR00326##

Example 6

(323) Polymerisable monomeric compound 6 is prepared as follows.

(324) ##STR00327## ##STR00328##

(325) 6a: To a solution of 4-bromo-3-hydroxy benzoic acid (9.8 g, 45.2 mmol) in DMF (140 ml) is added cesium carbonate (33.84 g, 103.9 mmol). To the resulted suspension (2-bromo-ethoxymethyl)-benzene (21.37 g, 99.3 mmol) is added. The reaction mixture is stirred at 110 C. for 3 hours. After cooling to room temperature, the reaction mixture is added into 800 ml water and extracted with 3250 ml ethyl acetate. The organic phase is washed with sat. aq. NaCl solution, dried over sodium sulfate. After removing solvent in vacuo, the oily residue is purified by column chromatography on silica gel with heptane/ethyl acetate 7:3 as eluent to provide 6a as colorless oil (22.1 g).

(326) 6b: To a solution of 6a (8.00 g, 15.5 mmol) and bis(pinacolato)diboron (4.08 g, 16.1 mmol) in 70 ml 1,4-dioxane was added sodium acetate (4.56 g, 46.6 mmol). After thoroughly degassing with argon, bis(triphenylphosphine)-palladium(II) chloride (0.45 g, 0.62 mmol) is added. The reaction mixture is heated to reflux and stirred for 4 hours. After cooling to room temperature, 200 ml dist. water is added. The aqueous phase is separated and extracted with methyl t-butyl ether. The organic phase is combined and dried over anhydrous sodium sulfate, and filtrated through silica gel. After removing solvent in vacuo, the product 6b is obtained as brownish oil (9.0 g).

(327) 6c: To a solution of 6b (9.00 g, 15.0 mmol) and 4-bromo-2-ethyl iodobenzene (4.98 g, 16.0 mmol) in 100 ml toluene was added 50 ml dist. water and 25 ml ethanol. Potassium carbonate (4.24 g, 40.0 mmol) is added. The resulted suspension is degassed carefully with argon. Tetrakis(triphenylphosphine)palladium(0) (0.66 g, 0.57 mmol) is then added. The reaction mixture is heated to reflux and stirred overnight. After cooling to room temperature, the reaction mixture is neutralized carefully with 6 M HCl acid under cooling to pH7. The aqueous phase is extracted with ethylacetate. The organic phase is combined and washed with sat. aq. NaCl solution, dried over sodium sulfate. After removing solvent in vacuo, the solid residue is purified by column chromatography with heptane/ethyl acetate 6:1 as eluent to provide 6c as yellowish oil (6.0 g).

(328) 6d: To a solution of sodium metaborate tetrahydrate (2.30 g, 16.5 mmol) in dist. water (20 ml) is added the solution of 6c (5.90 g, 9.19 mmol) and 4-(benzyloxy)phenyl boronic acid (2.51 g, 11.0 mmol) in 70 ml THF. After thoroughly degassing with argon, bis(triphenylphosphine)-palladium(II) chloride (0.37 g, 0.51 mmol) is added, followed by the addition of hydrazinium hydroxide (0.05 ml, 1 mmol). The reaction mixture is heated to reflux and stirred for 12 hours. After cooling to room temperature, the reaction mixture is carefully neutralized with 2 M HCl acid. The aqueous phase is separated and extracted with ethyl acetate. The organic phase is combined and dried over anhydrous sodium sulfate. After removing organic solvent, the oily residue is purified by column chromatography on silica gel with toluene/ethyl acetate 9:1 as eluent to afford 6d as colorless oil (4.4 g).

(329) 6e: A suspension of 6d (4.30 g, 6.0 mmol) in tetrahydrofuran (40 ml) is treated with palladium (5%) on activated charcoal (1.0 g) and submitted to hydrogenation for 18 hs. The catalyst is then filtered off. After removing solvent in vacuo, the oily residue is purified by column chromatography on silica gel with heptane/ethyl acetate solvent mixture as elute to provide 6e as colorless oil (2.3 g).

(330) 6: Methacrylic acid (2.11 g, 24.5 mmol) and 4-(dimethylamino)pyridine (0.10 g, 0.82 mmol) is added to a suspension of 6e (2.30 g, 5.44 mmol) in dichloromethane (30 ml). The reaction mixture is treated dropwise at 0 C. with a solution of N-(3-dimethylaminopropyl)-N-ethylcarbodiimide (3.89 g, 25.0 mmol) in dichloromethane (10 ml) and stirred for 20 hs at room temperature. The reaction mixture is concentrated in vacuo, and the oily residue is purified by column chromatography on silica gel with heptanes/ethyl acetate solvent mixture as eluent. The obtained product is recrystallized from heptane/ethanol 1:2 to afford white crystals of 6 (2.1 g, mp. 67 C.).

Mixture Example 1

(331) The nematic LC host mixture 1 is formulated as follows.

(332) TABLE-US-00005 CCH-501 9.00% cl.p. 70.0 C. CCH-35 14.00% n 0.0825 PCH-53 8.00% 3.5 PCH-304FF 14.00% .sub.|| 3.5 PCH-504FF 13.00% K.sub.3/K.sub.1 1.00 CCP-302FF 8.00% .sub.1 141 mPa s CCP-502FF 8.00% V.sub.0 2.10 V CCP-21FF 9.00% CCP-31FF 9.00% CPY-2-O2 8.00%

(333) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 1 at a concentration of 0.3% by weight.

Mixture Example 2

(334) The nematic LC host mixture 2 is formulated as follows.

(335) TABLE-US-00006 CY-3-O2 18.00% cl.p. +74.5 C. CPY-2-O2 10.00% n 0.1021 CPY-3-O2 10.00% 3.1 CCY-3-O2 9.00% .sub.|| 3.5 CCY-4-O2 4.00% K.sub.3/K.sub.1 1.16 CC-3-V 40.00% .sub.1 86 mPa s PYP-2-3 9.00% V.sub.0 2.29 V

(336) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 2 at a concentration of 0.3% by weight.

Mixture Example 3

(337) The nematic LC host mixture 3 is formulated as follows.

(338) TABLE-US-00007 CC-3-V 20.00% cl.p. 74.5 C. CC-3-V1 10.00% n 0.1084 CCH-34 8.00% 3.2 CCH-35 4.00% V.sub.0 2.33 V CCY-3-O1 5.50% K.sub.3/K.sub.1 1.04 CCY-3-O2 12.00% .sub.1 94 mPa s CPY-2-O2 2.00% CPY-3-O2 12.00% PY-3-O2 15.00% PY-4-O2 8.50% PYP-2-3 3.00%

(339) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 3 at a concentration of 0.3% by weight.

Mixture Example 4

(340) The nematic LC host mixture 4 is formulated as follows.

(341) TABLE-US-00008 CC-3-V 20.00% cl.p. 74.6 C. CC-3-V1 10.00% n 0.1042 CCH-35 9.00% 3.1 CCP-3-1 7.00% V.sub.0 2.48 V CCY-3-O2 13.00% K.sub.3/K.sub.1 1.13 CPY-3-O2 13.00% .sub.1 94 mPa s CY-3-O2 8.00% PY-3-O2 15.00% PY-4-O2 5.00%

(342) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 4 at a concentration of 0.3% by weight.

Mixture Example 5

(343) The nematic LC host mixture 5 is formulated as follows.

(344) TABLE-US-00009 CC-3-V 27.50% cl.p. 74.8 C. CC-3-V1 7.50% n 0.0986 CCH-23 3.00% 3.4 CCP-3-1 3.75% V.sub.0 2.26 V CCY-3-O2 12.50% K.sub.3/K.sub.1 1.16 CPY-2-O2 11.50% .sub.1 95 mPa s CPY-3-O2 10.50% CY-3-O2 15.50% PY-3-O2 3.00% PY-4-O2 5.25%

(345) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 5 at a concentration of 0.3% by weight.

Mixture Example 6

(346) The nematic LC host mixture 6 is formulated as follows.

(347) TABLE-US-00010 CC-3-V 41.50% cl.p. 74.6 C. CCP-3-1 2.00% n 0.0983 CCY-3-O1 5.25% 3.1 CCY-3-O2 12.50% V.sub.0 2.28 V CPY-2-O2 12.25% K.sub.3/K.sub.1 1.11 CPY-3-O2 7.50% .sub.1 85 mPa s CY-3-O2 5.50% PY-3-O2 3.50% PY-4-O2 10.00%

(348) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 6 at a concentration of 0.3% by weight.

Mixture Example 7

(349) The nematic LC host mixture 7 is formulated as follows.

(350) TABLE-US-00011 CC-3-V 27.50% cl.p. 75.6 C. CC-3-V1 8.00% n 0.0989 CCH-23 2.50% 3.4 CCP-3-1 3.00% V.sub.0 2.28 V CCY-3-O2 12.00% K.sub.3/K.sub.1 1.16 CCY-4-O2 2.00% .sub.1 94 mPa s CPY-2-O2 10.00% CPY-3-O2 10.50% CY-3-O2 15.50% CY-3-O4 1.00% PY-3-O2 15.00% PY-4-O2 7.00% PYP-2-3 1.00%

(351) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 7 at a concentration of 0.3% by weight.

Mixture Example 8

(352) The nematic LC host mixture 8 is formulated as follows.

(353) TABLE-US-00012 CC-3-V 41.50% cl.p. 74.5 C. CCY-3-O1 2.50% n 0.0984 CCY-3-O2 11.50% 3.3 CCY-3-O3 5.00% V.sub.0 2.29 V CPY-2-O2 5.00% K.sub.3/K.sub.1 1.15 CPY-3-O2 12.00% .sub.1 89 mPa s CY-3-O2 9.50% PY-3-O2 7.00% PY-4-O2 3.00% PYP-2-3 3.00%

(354) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 8 at a concentration of 0.3% by weight.

Mixture Example 9

(355) The nematic LC host mixture 9 is formulated as follows.

(356) TABLE-US-00013 CC-3-V 28.00% cl.p. 74.9 C. CCY-3-O1 10.00% n 0.1026 CCY-3-O2 1.00% 3.0 CCY-3-O3 6.00% V.sub.0 2.47 V CPY-2-O2 12.00% K.sub.3/K.sub.1 1.19 CPY-3-O2 3.00% .sub.1 90 mPa s CY-3-O2 12.00% PY-3-O2 10.00% PY-4-O2 15.00% PYP-2-3 3.00%

(357) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 9 at a concentration of 0.3% by weight.

Mixture Example 10

(358) The nematic LC host mixture 10 is formulated as follows.

(359) TABLE-US-00014 CC-3-V 15.00% cl.p. 74.4 C. CC-3-V1 9.00% n 0.1086 CCH-23 8.00% 3.2 CCH-34 7.50% V.sub.0 2.33 V CCY-3-O2 10.00% K.sub.3/K.sub.1 1.10 CCY-5-O2 8.00% .sub.1 102 mPa s CPY-2-O2 3.00% CPY-3-O2 8.50% CY-3-O2 7.00% PY-3-O2 16.00% PYP-2-3 8.00%

(360) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 10 at a concentration of 0.3% by weight.

Mixture Example 11

(361) The nematic LC host mixture 11 is formulated as follows.

(362) TABLE-US-00015 CC-3-V 42.00% cl.p. 73.5 C. CCY-3-O1 5.00% n 0.1007 CCY-3-O2 10.00% 3.5 CCY-4-O2 2.50% V.sub.0 2.15 V CPY-2-O2 10.00% K.sub.3/K.sub.1 1.13 CPY-3-O2 10.00% .sub.1 85 mPa s CY-3-O2 6.50% PY-3-O2 11.00% IS-18566 3.00%

(363) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 11 at a concentration of 0.3% by weight.

Mixture Example 12

(364) The nematic LC host mixture 12 is formulated as follows.

(365) TABLE-US-00016 CC-3-V 45.50% cl.p. 73.0 C. CCY-3-O1 3.00% n 0.1011 CCY-3-O2 11.00% 3.5 CCY-4-O2 3.50% V.sub.0 2.15 V CPY-2-O2 7.50% K.sub.3/K.sub.1 1.09 CPY-3-O2 10.00% .sub.1 79 mPa s CY-3-O2 2.00% PY-3-O2 11.50% IS-18566 6.00%

(366) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 12 at a concentration of 0.3% by weight.

Mixture Example 13

(367) The nematic LC host mixture 13 is formulated as follows.

(368) TABLE-US-00017 CC-3-V 34.50% cl.p. 75.0 C. CC-3-V1 8.00% n 0.1075 CCY-3-O1 7.00% 3.1 CCY-3-O2 11.50% V.sub.0 2.41 V CCY-4-O2 3.50% K.sub.3/K.sub.1 1.12 CPY-3-O2 11.50% .sub.1 84 mPa s PY-3-O2 13.00% PP-1-2V1 6.00% IS-18566 5.00%

(369) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 13 at a concentration of 0.3% by weight.

Mixture Example 14

(370) The nematic LC host mixture 14 is formulated as follows.

(371) TABLE-US-00018 CC-3-V 37.50% cl.p. 75.5 C. CC-3-V1 7.00% n 0.1080 CCY-3-O1 6.00% 3.0 CCY-3-O2 11.00% V.sub.0 2.41 V CPY-2-O2 4.50% K.sub.3/K.sub.1 1.12 CPY-3-O2 11.00% .sub.1 84 mPa s PY-3-O2 17.00% PGIY-2-O4 5.00% PP-1-2V1 1.00%

(372) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 14 at a concentration of 0.3% by weight.

Mixture Example 15

(373) The nematic LC host mixture 15 is formulated as follows.

(374) TABLE-US-00019 CC-3-V 39.00% cl.p. 75.0 C. CC-3-V1 7.00% n 0.1098 CCY-3-O1 1.50% 3.0 CCY-3-O2 5.00% V.sub.0 2.41 V CPY-2-O2 9.00% K.sub.3/K.sub.1 1.11 CPY-3-O2 6.00% .sub.1 82 mPa s PY-3-O2 11.50% PGIY-2-O4 16.00% PP-1-2V1 5.00%

(375) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 15 at a concentration of 0.3% by weight.

Mixture Example 16

(376) The nematic LC host mixture 16 is formulated as follows.

(377) TABLE-US-00020 CY-3-O2 16.50% cl.p. 74.0 C. CCY-4-O2 10.50% n 0.1069 CCY-5-O2 6.00% 3.2 CPY-2-O2 9.00% V.sub.0 2.18 CPY-3-O2 9.00% K.sub.3/K.sub.1 1.06 CCH-34 9.00% .sub.1 117 mPa s CCH-31 20.00% CCP-3-1 2.00% PYP-2-3 6.50% PYP-2-4 6.50% PCH-301 5.00%

(378) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 16 at a concentration of 0.3% by weight.

Mixture Example 17

(379) The nematic LC host mixture 17 is formulated as follows.

(380) TABLE-US-00021 CY-3-O2 16.50% cl.p. 74.5 C. CCY-4-O2 9.50% n 0.1070 CCY-5-O2 4.00% 3.2 CPY-2-O2 9.00% V.sub.0 2.19 CPY-3-O2 9.00% K.sub.3/K.sub.1 1.06 CCH-34 9.00% .sub.1 117 mPa s CCH-31 20.00% CCP-3-1 5.00% PYP-2-3 4.00% PYP-2-4 4.00% PCH-301 5.00% PGIY-2-O4 5.00%

(381) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 17 at a concentration of 0.3% by weight.

Mixture Example 18

(382) The nematic LC host mixture 18 is formulated as follows.

(383) TABLE-US-00022 CY-3-O2 12.00% cl.p. 74.0 C. CY-3-O4 10.00% n 0.1064 CCY-3-O2 6.00% 3.2 CCY-4-O2 6.50% V.sub.0 2.19 CCH-34 9.00% K.sub.3/K.sub.1 0.99 CCH-35 5.00% .sub.1 119 mPa s CCP-3-1 14.50% CCP-3-3 11.00% PYP-2-3 9.00% PYP-2-4 8.00% Y-4O-O4 9.00%

(384) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 18 at a concentration of 0.3% by weight.

Mixture Example 19

(385) The nematic LC host mixture 19 is formulated as follows.

(386) TABLE-US-00023 CY-3-O2 12.00% cl.p. 73.5 C. CY-3-O4 10.00% n 0.1065 CCY-3-O2 6.00% 3.3 CCY-4-O2 5.50% V.sub.0 2.18 CCH-34 8.50% K.sub.3/K.sub.1 1.00 CCH-35 5.00% .sub.1 119 mPa s CCP-3-1 15.00% CCP-3-3 11.50% PYP-2-3 5.50% PYP-2-4 5.00% PP-1-2V1 2.00% PGIY-2-O4 5.00% Y-4O-O4 9.00%

(387) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 19 at a concentration of 0.3% by weight.

Mixture Example 20

(388) The nematic LC host mixture 20 is formulated as follows.

(389) TABLE-US-00024 CC-3-V 28.50% cl.p. 74.5 C. CCP-31 12.50% n 0.1077 CCOY-2-O2 19.00% 3.2 CCOY-3-O2 11.50% V.sub.0 2.34 V PY-3-O2 13.50% K.sub.3/K.sub.1 0.91 PP-1-3 10.00% .sub.1 99 mPa s PYP-2-3 5.00%

(390) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 20 at a concentration of 0.3% by weight.

Mixture Example 21

(391) The nematic LC host mixture 21 is formulated as follows.

(392) TABLE-US-00025 CC-3-V1 9.00% cl.p. 75.4 C. CCH-23 14.00% n 0.1056 CCH-34 6.00% 2.8 CCH-35 6.00% V.sub.0 2.67 V CCP-3-1 7.00% K.sub.3/K.sub.1 1.07 CCY-3-O1 5.00% .sub.1 102 mPa s CCY-3-O2 10.00% CPY-3-O2 12.00% CY-3-O2 9.50% PP-1-2V1 8.50% PY-3-O2 12.00% PY-4-O2 1.00%

(393) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 21 at a concentration of 0.3% by weight.

Mixture Example 22

(394) The nematic LC host mixture 22 is formulated as follows.

(395) TABLE-US-00026 CC-3-V 37.00% cl.p. 75.0 C. CC-3-V1 7.00% n 0.1090 CCY-3-O2 5.00% 3.2 CLY-3-O2 10.00% V.sub.0 2.34 V CPY-2-O2 10.50% K.sub.3/K.sub.1 1.14 CPY-3-O2 10.50% .sub.1 87 mPa s PY-1-O4 10.00% PY-3-O2 9.00% PGIY-2-O4 1.00%

(396) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 22 at a concentration of 0.3% by weight.

Mixture Example 23

(397) The nematic LC host mixture 23 is formulated as follows.

(398) TABLE-US-00027 CC-3-V 34.50% cl.p. 74.5 C. CC-3-V1 8.00% n 0.1088 CCY-3-O1 9.00% 3.2 CCY-3-O2 5.50% V.sub.0 2.33 V CLY-3-O2 10.00% K.sub.3/K.sub.1 1.12 CPY-3-O2 5.00% .sub.1 90 mPa s PY-1-O4 10.00% PY-3-O2 10.00% PYP-2-3 3.00% PGIY-2-O4 5.00%

(399) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 23 at a concentration of 0.3% by weight.

Mixture Example 24

(400) The nematic LC host mixture 24 is formulated as follows.

(401) TABLE-US-00028 B-2O-O5 5.00% cl.p. 74.6 C. CC-3-V1 38.00% n 0.1086 CCY-3-O1 10.00% 3.2 CCY-3-O2 7.50% V.sub.0 2.34 V CLY-3-O2 10.00% K.sub.3/K.sub.1 1.11 CPY-3-O2 9.50% .sub.1 82 mPa s PY-3-O2 13.00% PYP-2-3 2.00% PGIY-2-O4 5.00%

(402) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 24 at a concentration of 0.3% by weight.

Mixture Example 25

(403) The nematic LC host mixture 25 is formulated as follows.

(404) TABLE-US-00029 CC-3-V 34.00% cl.p. 74.3 C. CC-3-V1 10.00% n 0.1091 CCY-3-O1 4.50% 3.2 CLY-3-O2 10.00% V.sub.0 2.34 V CPY-2-O2 10.50% K.sub.3/K.sub.1 1.12 CPY-3-O2 11.00% .sub.1 88 mPa s PY-1-O4 9.00% PY-3-O2 11.00%

(405) Six polymerisable mixtures are prepared by adding each one of RM1 to RM6, respectively, to nematic LC host mixture 25 at a concentration of 0.3% by weight.

(406) For comparison purposes further individual polymerisable mixtures are prepared by adding direactive monomer C1 of prior art to each of nematic LC host mixtures 1-25 at a concentration of 0.3% by weight, respectively, and by adding direactive monomer C2 of prior art to each of nematic LC host mixtures 1-25 at a concentration of 0.3% by weight, respectively,

(407) ##STR00329## ##STR00330##

Use Examples

(408) The polymerisable mixtures according to the invention and the polymerisable comparison mixtures are each inserted into a VA e/o test cell. The test cells comprise a VA-polyimide alignment layer (JALS-2096-R1) which is rubbed antiparallel (for the test cells with host mixture C the polyimide AL64101 was used). The LC-layer thickness d is approx. 4 m.

(409) Each test cell is irradiated with UV light having an intensity of 100 mW/cm.sup.2 for the time indicated with application of a voltage of 24 V.sub.rms (alternating current), causing polymerisation of the polymerisable monomeric compound.

(410) The VHR values of the polymerisable mixtures before and after UV exposure are measured as described above. The VHR values of the mixtures are shown in Table 1.

(411) TABLE-US-00030 TABLE 1 VHR values Host Host Host Host Host Host 1 + 1 + 1 + 1 + 1 + 1 + Host C1 RM1 RM2 RM3 RM4 RM5 1 + VHR/% RM6 0 min UV 98.2 98.6 98.8 98.7 98.1 98.8 98.9 2 h 97.6 98.2 98.7 98.6 98.9 98.5 98.9 Suntest.sup.1) Host Host Host Host Host Host 2 + 2 + 2 + 2 + 2 + 2 + Host C1 RM1 RM2 RM3 RM4 RM5 2 + VHR/% RM6 0 min UV 98.3 97.5 98.3 89.0 95.8 97.6 98.5 2 h 85.6 89.2 93.0 93.4 94.7 90.1 92.5 Suntest.sup.1) 10 min UV 74.8 88.4 92.0 89.4 95.1 91.5 85.8 Host Host Host Host 3 + 3 + 3 + 3 + C1 RM1 RM2 RM4 VHR/% 0 min UV 98.3 98.4 98.0 98.0 2 min UV 94.8 97.5 96.7 96.8 15 min UV 93.6 96.7 95.3 96.9 2 min UV + 95.5 96.4 96.1 97.2 2 h suntest.sup.1),2) Host Host 4 + 4 + C1 RM1 VHR/% 0 min UV 98.6 98.4 5 min UV 96.3 97.6 15 min UV 94.0 96.4 5 min UV + 96.0 97.2 2 h suntest.sup.1),2) .sup.1)Suntest means a second irradiation step with lower UV intensity but longer exposure time than the first step. .sup.2)In the test cells for these mixtures the polyimide AL64101 was used.

(412) As can be seen from Table 1, the VHR values of polymerisable mixtures comprising RM1 to RM6 according to the present invention after UV exposure are higher than the VHR values of polymerisable mixture comprising monomer C1, especially in polymerisable mixtures comprising host mixture 2 and 4 with alkenyl compounds.

(413) In addition, RM1 to RM6 according to the present invention do either show only a very small decrease or even an increase of the VHR after 2h suntest compared to the initial VHR value.

(414) In order to determine the polymerisation rate, the residual content of unpolymerised RM (in % by weight) in the test cells is measured by HPLC after various exposure times. For this purpose each mixture is polymerised in the test cell under the stated conditions. The mixture is then rinsed out of the test cell using MEK (methyl ethyl ketone) and measured.

(415) The residual concentrations of the respective monomer in the mixture after different exposure times are shown in Table 2.

(416) TABLE-US-00031 TABLE 2 Residual monomer content Host Host Host Host Host Host 1 + 1 + 1 + 1 + 1 + 1 + Host Time/ C1 RM1 RM2 RM3 RM4 RM5 1 + min Residual RM/% RM6 0 0.3 0.3 0.3 0.3 0.3 0.3 0.3 2 0.264 0.221 0.217 0.077 0.273 0.266 0.146 4 0.203 0.141 0.132 0.013 0.154 0.243 0.06 6 0.173 0.089 0.079 0.003 0.091 0.192 0.032 Host Host Host Host Host Host 2 + 2 + 2 + 2 + 2 + 2 + Host Time/ C1 RM1 RM2 RM3 RM4 RM5 2 + min Residual RM/% RM6 0 0.3 0.3 0.3 0.3 0.3 0.3 0.3 2 0.185 0.141 0.136 0.058 0.164 0.198 0.118 6 0.067 0.054 0.046 0.007 0.064 0.073 0.022 Host Host Host Host Host 3 + 3 + 3 + 3 + 3 + Time/ C1 RM1 RM2 RM3 RM4 min Residual RM/% 0 0.3 0.3 0.3 0.3 0.3 0.5 0.256 0.227 0.244 0.089 0.239 1 0.199 0.135 0.156 0.037 0.156 2 0.142 0.091 0.082 0.005 0.103 5 0.05 0.062 0.042 0.000 0.048 Host Host 4 + 4 + Time/ C1 RM1 min Residual RM/% 0 0.3 0.3 1 0.278 0.232 2 0.249 0.162 3 0.209 0.101 5 0.146 0.043

(417) As can be seen from Table 2, significantly more rapid and complete polymerisation is achieved in PSA displays containing a polymerisable mixture with RM1 to RM6 according to the present invention, compared to PSA displays containing a polymerisable mixture with monomer C1.

(418) The tilt angle is determined before and after UV irradiation by a crystal rotation experiment (Autronic-Melchers TBA-105).

(419) The tilt angles are shown in Table 3.

(420) TABLE-US-00032 TABLE 3 Tilt angles Host Host Host Host Host Host 1 + 1 + 1 + 1 + 1 + 1 + Host UV-Time/ C1 RM1 RM2 RM3 RM4 RM5 1 + sec Pretilt Angle/ RM6 0 89.6 88.7 88.6 88.9 89.1 88.9 89.3 30 89.0 87.9 85.9 82.8 88.1 88.9 87.3 60 88.2 85.2 83.4 71.4 86.2 88.0 79.5 120 84.9 81.4 78.6 66.6 81.4 86.4 73.3 Host Host Host Host Host Host 2 + 2 + 2 + 2 + 2 + 2 + Host UV-Time/ C1 RM1 RM2 RM3 RM4 RM5 1 + sec Pretilt Angle/ RM6 0 88.8 88.9 88.6 88.8 88.8 88.5 89.2 120 77.2 77.2 76.6 71.2 78.4 77.2 74.1 Host Host Host 3 + 3 + 3 + Host Host UV-Time/ C1 RM1 RM2 3 + 3 + sec Pretilt Angle/ RM3 RM4 0 89.1 89.7 88.9 89.7 89.7 60 86.4 84.7 74.3 78.3 80.5 120 78.0 76.7 68.2 69.8 75.1 180 76.1 73.8 64.8 68.4 71.8 300 73.5 71.1 62.0 66.8 70.6 Host Host 4 + 4 + UV-Time/ C1 RM1 sec Pretilt Angle/ 0 89.1 89.4 60 89.2 89.3 120 89.4 88.4 180 86.9 83.2 300 80.0 74.8

(421) As can be seen from Table 3, a small tilt angle after polymerisation is achieved quickly in PSA displays containing a polymerisable mixture with RM1 to RM6 according to the present invention, which is smaller than in a PSA display containing a polymerisable mixture with monomer C1.

(422) While the aforementioned values have been obtained after polymerisation of the polymerisable LC medium with a metal-halide UV lamp and a 320 nm UV filter, the following tables show values obtained after irradiation with the same UV lamp, but with a 340 nm UV filter.

(423) This demonstrates the improved performance of the RMs according to the present invention when using UV lamps with emission spectra shifted to longer wavelengths and/or by using UV lamps with lower intensity.

(424) Test cells and PI are similar to the example above, e.g. for the test cells with host mixture 3 the polyimide AL64101 was used etc.

(425) TABLE-US-00033 TABLE 4 VHR values Host Host 3 + C2 3 + RM3 VHR/% 0 min UV 98.7 98.6 10 min UV 93.9 97.7 20 min UV 94.7 97.7

(426) The VHR values of polymerisable mixtures comprising RM3 are compared with a polymerisable mixture comprising RM C2 instead of RM C1, because C2 has a polymerization speed that is better comparable to RM3. As shown in Table 5 below, Cl shows slower polymerization with the 340 nm filter and is therefore disadvantageous.

(427) As shown in Table 4, after UV exposure the VHR values with RM3 are higher than the VHR values with monomer C2 of prior art.

(428) TABLE-US-00034 TABLE 5 Residual monomer content Host Host Host Time/ 3 + C1 3 + C2 3 + RM3 min Residual RM/% 0 0.3 0.3 0.3 5 0.279 0.145 0.053 10 0.188 0.054 0.015

(429) As can be seen from Table 5, significantly more rapid and complete polymerisation is achieved in PSA displays containing a polymerisable mixture with RM3 according to the present invention, compared to PSA displays containing a polymerisable mixture with monomer Cl or C2.

(430) TABLE-US-00035 TABLE 6 Tilt angles Host Host Host UV-Time/ 3 + C1 3 + C2 3 + RM3 min Pretilt Angle/ 0 89.8 89.6 89.8 2 89.7 86.4 75.7 6 83.8 80.4 69.4

(431) As can be seen from Table 6, a small tilt angle after polymerisation is achieved quickly in PSA displays containing a polymerisable mixture with RM3 according to the present invention, which is smaller than in a PSA display containing a polymerisable mixture with monomer Cl or C2.

(432) For measuring the solubility, RM1 to RM4, respectively, and monomer Cl of prior art are each dissolved at various concentrations from 0.3 to 3.0% by weight in the commercially available nematic LC mixture MJ011412 (Merck Japan Ltd.). The samples are stored for 1000h at room temperature and checked if they remain a homogeneous solution. Afterwards the samples are centrifugated and filtrated, and the residual monomer concentration in the supernatant liquid is determined.

(433) Maximum residual monomer concentration after 1000h at RT:

(434) C1: 0.46%

(435) RM1: 1.0%

(436) RM2: 1.0%

(437) RM3: 1.0%

(438) RM4: 1.0%

(439) It can be seen that RM1 to RM4 according to the present invention have better solubility in the LC host mixture than monomer Cl of prior art.

(440) 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.

(441) 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.

(442) 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.

(443) The entire disclosures of all applications, patents and publications, cited herein and of corresponding EP application No. 14002646.9, filed Jul. 30, 2014, are incorporated by reference herein.