Polymerisable compounds and the use thereof in liquid-crystal displays

Abstract

The present invention relates to a mixture comprising a not fully aromatic polymerisable compound and a polymerisable photoinitiator, to liquid-crystal (LC) media comprising them, and to the use of the polymerisable 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 mixture comprising one or more compounds of formula I and one or more compounds of formula II ##STR00582## wherein the individual radicals, independently of each other and on each occurrence identically or differently, have the following meanings R P, P-Sp-, H, F, Cl, Br, I, —CN, —NO.sub.2, —NCO, —NCS, —OCN, —SCN, SF.sub.5 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)—, —C≡C—, —N(R.sup.00)—, —O—, —S—, —CO—, —CO—O—, —O—CO—, —O—CO—O— 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 each be replaced by F, Cl, Br, I, CN, P or P-Sp-, P a polymerizable group, Sp a spacer group or a single bond, A.sup.1, A.sup.3 straight-chain, branched or cyclic alkylene with 1 to 20 C atoms, wherein one or more non-adjacent CH.sub.2-groups are optionally replaced by —CR.sup.0═CR.sup.00—, —C≡C—, —O—, —S—, —CO—, —CO—O—, —O—CO—, —O—CO—O— 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 or Cl, A.sup.2, A.sup.4 arylene or heteroarylene having 5 to 20 ring atoms, which optionally contains fused rings, which are optionally substituted by one or more groups L or P-Sp-, Z.sup.1-4 —O—, —S—, —CO—, —CO—O—, —O—CO—, —O—CO—O—, —OCH.sub.2—, —CH.sub.2O—, —SCH.sub.2—, —CH.sub.2S—, —CF.sub.2O—, —OCF.sub.2—, —CF.sub.2S—, —SCF.sub.2—, —(CH.sub.2).sub.n1—, —CF.sub.2CH.sub.2—, —CH.sub.2CF.sub.2—, —(CF.sub.2).sub.n1—, —CH═CH—, —CF═CF—, —CH═CF—, —CF═CH—, —C≡C—, —CH═CH—CO—O—, —O—CO—CH═CH—, —CH.sub.2—CH.sub.2—CO—O—, —O—CO—CH.sub.2—CH.sub.2—, —CR.sup.0R.sup.00—, or a single bond, R.sup.0, R.sup.00 H or alkyl having 1 to 12 C atoms, L F, Cl, —CN, P-Sp- 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 —CR.sup.0═CR.sup.00—, —C≡C—, —O—, —S—, —CO—, —CO—O—, —O—CO—, —O—CO—O— 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 P-Sp-, F or Cl, R.sup.1, R.sup.2 straight-chain or branched alkyl with 1 to 6 C atoms, R.sup.3 OH or morpholine-1-yl, a, b, c, d 0, 1, 2 or 3, with a+c≥1, g 1, 2, 3 or 4, n1 1, 2, 3 or 4, r 0, 1, 2, 3 or 4, p 1, 2 or 3, with p+r≤5, and wherein in formula II in case of g≥2 the groups (P-Sp)p and —C(═O)—CR.sup.1R.sup.2R.sup.3 are linked to different terminal benzene rings, and in case of g≥3 all benzene rings are connected with each other via para-positions.

2. The mixture according to claim 1, wherein in formula I Z.sup.1, Z.sup.2, Z.sup.3 and Z.sup.4 are a single bond.

3. The mixture according to claim 1, wherein in formula I A.sup.1 and A.sup.3 are trans-1,4-cyclohexylene which is optionally substituted by one or more groups L or P-Sp-, and A.sup.2 and A.sup.4 are selected from 1,4-phenylene, pyridine and thiophene which is optionally substituted by one or more groups L or P-Sp-.

4. The mixture according to claim 1, wherein in formula I and II all groups Sp are a single bond.

5. The mixture according to claim 1, wherein in formula I -(A.sup.1-Z.sup.1).sub.a-(A.sup.2-Z.sup.2).sub.b-(A.sup.3-Z.sup.3).sub.c-(A.sup.4-Z.sup.4).sub.d— is selected from the following formulae ##STR00583## wherein i is an integer from 1 to 12, and the cyclohexylene and benzene rings are optionally substituted by one or more groups L or P-Sp-.

6. The mixture according to claim 1, wherein the compounds of formula I are selected from the following subformulae ##STR00584## wherein P, Sp and L have independently of each other, and on each occurrence identically or differently, one of the meanings given in claim 1, i is an integer from 1 to 12 r is 0, 1, 2, 3 or 4, and s is 0, 1, 2 or 3.

7. The mixture according to claim 1, wherein the compounds of formula II are selected from the following formulae ##STR00585## wherein P, Sp, L, R.sup.1-3 and r have the meanings given in claim 1, h is 0, 1 or 2, p1 is 0 or 1, p2 is 0, 1 or 2, with p1+p2≥1 and p1+p2+r≤5.

8. The mixture according to claim 7, wherein in the compounds of formula II, IIA and IIB the group —C(═O)—CR.sup.1R.sup.2R.sup.3 is selected from the following groups ##STR00586## wherein Me is methyl, the asterisk * denotes the linkage to the benzene ring in formula II, IIA or IIB, and P and Sp have the meanings given in claim 7.

9. The mixture according to claim 7, wherein the compounds of formula II, IIA and IIB are selected from the following formulae ##STR00587## wherein P, Sp, L, R.sup.1-3, r and h have the meanings given in claim 7.

10. The mixture according to claim 9, wherein the compounds of formula II, IIA, IIB, IIA1-IIA3 and IIB1-IIB5 are selected from the following subformulae ##STR00588## ##STR00589## ##STR00590## ##STR00591## ##STR00592## ##STR00593## ##STR00594## wherein P, Sp, L and r have the meanings given in claim 9 and Me is methyl.

11. A liquid crystal (LC) medium comprising one or more compounds of formula I and one or more compounds of formula II as defined in claim 1.

12. The LC medium of claim 11, wherein said medium comprises a polymerizable component A) comprising one or more compounds of formula I and one or more compounds of formula II, and a liquid-crystalline LC component B) comprising one or more mesogenic or liquid-crystalline compounds.

13. The LC medium of claim 11, wherein said medium comprises one or more compounds of the formulae CY and/or PY: ##STR00595## in which a, b ##STR00596## R.sup.1, R.sup.2, Z.sup.x, and L.sup.1-4 have the following meanings: a denotes 1 or 2, b denotes 0 or 1, ##STR00597## denotes ##STR00598## 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 each be replaced by —O—, —CH═CH—, —CO—, —O—CO— or —CO—O— in such a way that O atoms are not linked directly to one another, Z.sup.x denotes —CH═CH—, —CH.sub.2O—, —OCH.sub.2—, —CF.sub.2O—, —OCF.sub.2—, —O—, —CH.sub.2—, —CH.sub.2CH.sub.2— or a single bond, L.sup.1-4 each, independently of one another, denote F, Cl, OCF.sub.3, CF.sub.3, CH.sub.3, CH.sub.2F, CHF.sub.2.

14. The LC medium according to claim 11, wherein the medium comprises one or more compounds selected from the following formulae: ##STR00599## in which R.sup.A1, R.sup.A2, ##STR00600## Z.sup.x, L.sup.1-4, x, and z have the following meanings: ##STR00601## R.sup.A1 alkenyl having 2 to 9 C atoms or, if at least one of the rings X, Y and Z denotes cyclohexenyl, R.sup.A1 can also be alkyl having 1 to 12 C atoms, in which, in addition, one or two non-adjacent CH.sub.2 groups may each be replaced by —O—, —CH═CH—, —CO—, —OCO— or —COO— in such a way that O atoms are not linked directly to one another, R.sup.A2 alkyl having 1 to 12 C atoms, in which, in addition, one or two non-adjacent CH.sub.2 groups may each be replaced by —O—, —CH═CH—, —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—, —CH═CH—, —CF.sub.2O—, —OCF.sub.2—, —CH.sub.2O—, —OCH.sub.2—, —CO—O—, —O—CO—, —C.sub.2F.sub.4—, —CF═CF—, —CH═CH—CH.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.

15. The LC medium according to claim 11, wherein the medium comprises one or more compounds of the following formula: ##STR00602## in which the individual radicals have the following meanings: ##STR00603## denotes ##STR00604## ##STR00605## denotes ##STR00606## 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 each be replaced by —O—, —CH═CH—, —CO—, —O—CO— or —CO—O— in such a way that O atoms are not linked directly to one another, Z.sup.y denotes —CH.sub.2CH.sub.2—, —CH═CH—, —CF.sub.2O—, —OCF.sub.2—, —CH.sub.2O—, —OCH.sub.2—, —COO—, —OCO—, —C.sub.2F.sub.4—, —CF═CF— or a single bond.

16. The LC medium according to claim 11, wherein the compounds of formula I and II are polymerized.

17. A process of preparing an LC medium of claim 11, comprising mixing one or more mesogenic or liquid-crystalline compounds with one or more compounds of formula I and II.

18. An LC display comprising an LC medium as defined in claim 11.

19. The LC display of claim 18, which is a PSA display or a polymer stabilized SA-VA display.

20. The LC display of claim 19, which is a PS-VA, PS-OCB, PS-IPS, PS-FFS, PS-UB-FFS, PS-posi-VA, PS-TN, SA-VA or SA-FFS display.

21. The LC display of claim 19, wherein the display comprises 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 comprising one or more compounds of formula I and II, wherein the compounds are polymerized between the substrates of the display.

22. The LC display of claim 19, wherein the display 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 said LC medium.

23. The LC display of claim 22, wherein the display comprises a first and/or second alignment layer that imparts to the LC molecules homeotropic alignment.

24. The LC display according to claim 23, wherein the display comprises a first and/or second alignment layer comprising a polyimide which is optionally rubbed or is prepared by a photoalignment method.

25. A process for the production of an LC display according to claim 21, comprising the steps of providing an LC medium comprising one or more compounds of formula I and II, between the substrates of the display, and polymerizing the compounds, optionally while a voltage is applied to the electrodes at least partially during the polymerization.

26. The process according to claim 25, wherein the polymerization is carried out in one step.

27. The process according to claim 26, wherein the polymerization is carried out in a first polymerization step while applying a voltage, and subsequently in a second polymerization step without an applied voltage.

28. The mixture according to claim 1, wherein R.sup.2 is methyl.

Description

DETAILED DESCRIPTION OF THE INVENTION

(1) An LC medium containing a compound of formula I and a compound of formula II shows the following advantageous properties when used in PSA or polymer stabilised SA-VA displays: a suitable tilt generation which is inside a certain process window, fast polymerization leading to minimal residues of RM after the UV-process, a high voltage-holding-ratio after the UV-process, good tilt stability, sufficient stability against heat, sufficient solubility in organic solvents typically used in display manufacture.

(2) Also the LC medium according to the present invention enables the use of non-aromatic RMs in PSA technology, which provides the following advantages: since non-aromatic RMs are not reactive under current standard UV-A exposure, the presence of residue RMs after processing does not have negative effects on the LC mixture performance parameters, such as VHR, tilt generation or tilt stability, it is possible to reduce, and preferably eliminate, the second UV exposure step which is commonly applied to remove residue RMs after the first UV exposure step, the rate of polymerization and tilt generation can be easily controlled by varying the amount of polymerisable photoinitiator, for example in the range from 10 to 500 ppm, the non-aromatic RMs usually have better solubility in LC-mixture than aromatic RMs.

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

(4) 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.

(5) 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.

(6) 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”.

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

(8) 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”.

(9) 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.

(10) 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.

(11) 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.

(12) Above and below,

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

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

(15) In a group

(16) ##STR00004##
the single bond shown between the two ring atoms can be attached to any free position of the ring.

(17) Above and below “organic group” denotes a carbon or hydrocarbon group.

(18) “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, —C≡C—) 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.

(19) “Halogen” denotes F, Cl, Br or I, preferably F or Cl. —CO—, —C(═O)— and —C(O)— denote a carbonyl group, i.e.

(20) ##STR00005##
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.

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

(22) 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.

(23) 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.

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

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

(26) 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.x)═C(R.sup.x)—, —C≡C—, —N(R.sup.x)—, —O—, —S—, CO—, —CO—O—, —O—CO—, —O—CO—O— in such a way that O and/or S atoms are not linked directly to one another.

(27) R.sup.x 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—, —CO—O—, —O—CO—, —O—CO—O— 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.

(28) 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.

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

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

(31) 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.

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

(33) 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.

(34) 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.

(35) 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, penta-cene, benzopyrene, fluorene, indene, indenofluorene, spirobifluorene, etc.

(36) 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, benzothiophene, benzothiadiazothiophene, or combinations of these groups.

(37) 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.

(38) 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.

(39) 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.

(40) 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—.

(41) 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.

(42) 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.

(43) 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,

(44) 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—, —CO—O—, —O—CO—, —O—CO—O— 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 Y.sup.1 denotes halogen.

(45) “Substituted silyl or aryl” preferably means substituted by halogen, —CN, R.sup.0, —OR.sup.0, —CO—R.sup.0, —CO—O—R.sup.0, —O—CO—R.sup.0 or —O—CO—O—R.sup.0, wherein R.sup.0 denotes H or alkyl with 1 to 20 C atoms.

(46) Particularly preferred substituents L.sup.S 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.

(47) ##STR00006##

(48) ##STR00007##
in which L has one of the meanings indicated above.

(49) 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 C═C double bond or —C≡C— triple bond, and groups which are suitable for polymerisation with ring opening, such as, for example, oxetane or epoxide groups.

(50) Preferred groups P are selected from the group consisting of CH.sub.2═CW.sup.1—CO—O—, CH.sub.2═CW.sup.1—CO—,

(51) ##STR00008##
CH.sub.2═CW.sup.2—(O).sub.k3—, CW.sup.1═CH—CO—(O).sub.k3—, CW.sup.1═CH—CO—NH—, CH.sub.2═CW.sup.1—CO—NH—, CH.sub.3—CH═CH—O—, (CH.sub.2═CH).sub.2CH—OCO—, (CH.sub.2═CH—CH.sub.2).sub.2CH—OCO—, (CH.sub.2═CH).sub.2CH—O—, (CH.sub.2═CH—CH.sub.2).sub.2N—, (CH.sub.2═CH—CH.sub.2).sub.2N—CO—, HO—CW.sup.2W.sup.3—, HS—CW.sup.2W.sup.3—, HW.sup.2N—, HO—CW.sup.2W.sup.3—NH—, CH.sub.2═CW.sup.1—CO—NH—, CH.sub.2═CH—(COO).sub.k1-Phe-(O).sub.k2—, CH.sub.2═CH—(CO).sub.k1-Phe-(O).sub.k2—, Phe-CH═CH—, 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.

(52) Very preferred groups P are selected from the group consisting of CH.sub.2═CW.sup.1—CO—O—, CH.sub.2═CW.sup.1—CO—,

(53) ##STR00009##
CH.sub.2═CW.sup.2—O—, CH.sub.2═CW.sup.2—, CW.sup.1═CH—CO—(O).sub.k3—, CW.sup.1═CH—CO—NH—, CH.sub.2═CW.sup.1—CO—NH—, (CH.sub.2═CH).sub.2CH—OCO—, (CH.sub.2═CH—CH.sub.2).sub.2CH—OCO—, (CH.sub.2═CH).sub.2CH—O—, (CH.sub.2═CH—CH.sub.2).sub.2N—, (CH.sub.2═CH—CH.sub.2).sub.2N—CO—, CH.sub.2═CW.sup.1—CO—NH—, CH.sub.2═CH—(COO).sub.k1-Phe-(O).sub.k2—, CH.sub.2═CH—(CO).sub.k1-Phe-(O).sub.k2—, Phe-CH═CH— 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.

(54) Very particularly preferred groups P are selected from the group consisting of CH.sub.2═CW.sup.1—CO—O—, in particular CH.sub.2═CH—CO—O—, CH.sub.2═C(CH.sub.3)—CO—O— and CH.sub.2═CF—CO—O—, furthermore CH.sub.2═CH—O—, (CH.sub.2═CH).sub.2CH—O—CO—, (CH.sub.2═CH).sub.2CH—O—,

(55) ##STR00010##

(56) 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.

(57) If the spacer group 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 linear or branched 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—, —CO—O—, —O—CO—, —O—CO—O—, —S—CO—, —CO—S—, —N(R.sup.0)—CO—O—, —O—CO—N(R.sup.0)—, —N(R.sup.0)—CO—N(R.sup.00)—, —CH═CH— or —≡C— in such a way that O and/or S atoms are not linked directly to one another, X″ denotes —O—, —S—, —CO—, —CO—O—, —O—CO—, —O—CO—O—, —CO—N(R.sup.0)—, —N(R.sup.0)—CO—, —N(R.sup.0)—CO—N(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—, —CH═N—, —N═CH—, —N═N—, —CH═CR.sup.0—, —CY.sup.2═CY.sup.3—, —C≡C—, —CH═CH—CO—O—, —O—CO—CH═CH— 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.

(58) X″ is preferably —O—, —S—, —CO—, —COO—, —OCO—, —O—COO—, —CO—NR.sup.0—, —NR.sup.0—CO—, —NR.sup.0—CO—NR.sup.00— or a single bond.

(59) Typical spacer groups Sp and -Sp″—X″— are, for example, —(CH.sub.2).sub.p1—, —(CH.sub.2).sub.p1—O—, —(CH.sub.2).sub.p1—O—CO—, —(CH.sub.2).sub.p1—CO—O—, —(CH.sub.2).sub.p1—O—CO—O—, —(CH.sub.2CH.sub.2O).sub.q1—CH.sub.2CH.sub.2—, —CH.sub.2CH.sub.2—S—CH.sub.2CH.sub.2—, —CH.sub.2CH.sub.2—NH—CH.sub.2CH.sub.2— or —(SiR.sup.0R.sup.00—O).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.

(60) Particularly preferred groups Sp and -Sp″-X″— are —(CH.sub.2).sub.p1—, —(CH.sub.2).sub.p1—O—, —(CH.sub.2).sub.p1—O—CO—, —(CH.sub.2).sub.p—CO—O—, —(CH.sub.2).sub.p—O—CO—O—, in which p1 and q1 have the meanings indicated above.

(61) 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.

(62) In a preferred embodiment of the invention the compounds of formula I and II and their subformulae contain a spacer group Sp that is substituted by one or more polymerisable groups P, so that the group Sp-P corresponds to Sp(P).sub.s, with s being ≥2 (branched polymerisable groups).

(63) Preferred compounds of formula I and II according to this preferred embodiment are those wherein s is 2, i.e. compounds which contain a group Sp(P).sub.2. Very preferred compounds of formula I according to this preferred embodiment contain a group selected from the following formulae:
—X-alkyl-CHPP  S1
—X-alkyl-CH((CH.sub.2).sub.aaP)((CH.sub.2).sub.bbP)  S2
—X—N((CH.sub.2).sub.aaP)((CH.sub.2).sub.bbP)  S3
—X-alkyl-CHP—CH.sub.2—CH.sub.2P  S4
—X-alkyl-C(CH.sub.2P)(CH.sub.2P)—C.sub.aaH.sub.2aa+1  S5
—X-alkyl-CHP—CH.sub.2P  S6
—X-alkyl-CPP—C.sub.aaH.sub.2aa+1  S7
—X-alkyl-CHPCHP—C.sub.aaH.sub.2aa+1  S8
in which P is as defined in formula I, alkyl denotes a single bond or straight-chain or branched alkylene having 1 to 12 C atoms which is unsubstituted or mono- or polysubstituted by F, Cl or CN and in which one or more non-adjacent CH.sub.2 groups may each, independently of one another, be replaced by —C(R.sup.0)═C(R.sup.0)—, —C≡C—, —N(R.sup.0)—, —O—, —S—, —CO—, —CO—O—, —O—CO—, —O—CO—O— in such a way that O and/or S atoms are not linked directly to one another, where R.sup.0 has the meaning indicated above, aa and bb each, independently of one another, denote 0, 1, 2, 3, 4, 5 or 6, X has one of the meanings indicated for X″, and is preferably O, CO, SO.sub.2, O—CO—, CO—O or a single bond.

(64) Preferred spacer groups Sp(P).sub.2 are selected from formulae S1, S2 and S3.

(65) Very preferred spacer groups Sp(P).sub.2 are selected from the following subformulae:
—CHPP  S1a
—O—CHPP  S1b
—CH.sub.2—CHPP  S1c
—OCH.sub.2—CHPP  S1d
—CH(CH.sub.2—P)(CH.sub.2—P)  S2a
—OCH(CH.sub.2—P)(CH.sub.2—P)  S2b
—CH.sub.2—CH(CH.sub.2—P)(CH.sub.2—P)  S2c
—OCH.sub.2—CH(CH.sub.2—P)(CH.sub.2—P)  S2d
—CO—NH((CH.sub.2).sub.2P)((CH.sub.2).sub.2P)  S3a

(66) In the compounds of formula I and II and their subformulae as described above and below, P is preferably selected from the group consisting of vinyloxy, acrylate, methacrylate, fluoroacrylate, chloroacrylate, oxetane and epoxide, most preferably from acrylate and methacrylate.

(67) Further preferred are compounds of formula I and II and their subformulae as described above and below, wherein all polymerisable groups P that are present in the compound have the same meaning, and very preferably denote acrylate or methacrylate, most preferably methacrylate.

(68) In the compounds of formula I and its subformulae as described above and below, R preferably denotes P-Sp-.

(69) Further preferred are compounds of formula I wherein R is selected from F, Cl or CN.

(70) Further preferred are compounds of formula I wherein R is selected from 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 (R.sup.0)═C(R.sup.00)—, —C≡C—, —N(R.sup.0)—, —O—, —S—, —CO—, —CO—O—, —O—CO—, —O—CO—O— 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 very preferably R is selected from 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 2 C atoms and the branched radicals have at least 3 C atoms).

(71) Further preferred are compounds of formula I and II and their subformulae as described above and below, wherein Sp denotes a single bond or —(CH.sub.2).sub.p1—, —O—(CH.sub.2).sub.p1—, —O—CO—(CH.sub.2).sub.p1, or —CO—O—(CH.sub.2).sub.p1, wherein p1 is 2, 3, 4, 5 or 6, and, if Sp is —O—(CH.sub.2).sub.p1—, —O—CO—(CH.sub.2).sub.p1 or —CO—O—(CH.sub.2).sub.p1 the O-atom or CO-group, respectively, is linked to the benzene ring.

(72) Further preferred are compounds of formula I and II and their subformulae as described above and below, wherein at least one group Sp is a single bond.

(73) Further preferred are compounds of formula I and II and their subformulae as described above and below, wherein at least one group Sp is different from a single bond, and is preferably selected from —(CH.sub.2).sub.p1—, —O—(CH.sub.2).sub.p1—, —O—CO—(CH.sub.2).sub.p1, or —CO—O—(CH.sub.2).sub.p1, wherein p1 is 2, 3, 4, 5 or 6, and, if Sp is —O—(CH.sub.2).sub.p1—, —O—CO—(CH.sub.2).sub.p1 or —CO—O—(CH.sub.2).sub.p1 the O-atom or CO-group, respectively, is linked to the benzene ring.

(74) Very preferred groups -(A.sup.1-Z.sup.1).sub.a-(A.sup.2-Z.sup.2).sub.b-(A.sup.3-Z.sup.3).sub.c-(A.sup.4-Z.sup.4).sub.d— in formula I are selected from the following formulae

(75) ##STR00011##
wherein i is an integer from 1 to 12, and the cyclohexlene and bezene rings are optionally substituted by one or more groups L or P-Sp-.

(76) Preferred compounds of formula I are selected from the following subformulae

(77) ##STR00012## ##STR00013##
wherein P, Sp and L have independently of each other, and on each occurrence identically or differently, one of the meanings given in formula I or one of the preferred meanings as given above and below, i is as defined in formula A4, r is 0, 1, 2, 3 or 4, preferably 0, 1 or 2, and s is 0, 1, 2 or 3, preferably 0 or 1.

(78) Very preferred compounds of formula I are selected from the following formulae

(79) ##STR00014## ##STR00015## ##STR00016## ##STR00017## ##STR00018##
wherein i is as defined above and is preferably 3, 4, 5 or 6.

(80) The compounds of formula II are preferably selected from the following formulae

(81) ##STR00019##
wherein P, Sp, L, R.sup.1-3 and r have the meanings given in formula II, h is 0, 1 or 2, p1 is 0 or 1, p2 is 0, 1 or 2, preferably 0 or 1, with p1+p2≥1 and p1+p2+≤5.

(82) In the compounds of formula II, IIA and IIB the group —C(═O)—CR.sup.1R.sup.2R.sup.3 is preferably selected from the following groups

(83) ##STR00020##
wherein Me is methyl, the asterisk * denotes the linkage to the terminal benzene ring in formula II, IIA and IIB, P and Sp have the meanings given above and below, P is preferably acrylate or methacrylate, very preferably methacrylate, and Sp is preferably a single bond.

(84) Preferred compounds of formula II, IIA and IIB are selected from the following formulae

(85) ##STR00021## ##STR00022##
wherein P, Sp, L, R.sup.1-3, r and h have the meanings given in formula II.

(86) Preferred compounds of formula II, IIA, IIB, IIA1-IIA3 and IIB1-11B5 are selected from the following subformulae

(87) ##STR00023## ##STR00024## ##STR00025## ##STR00026## ##STR00027## ##STR00028## ##STR00029## ##STR00030##
wherein P, Sp, L and r have the meanings given in formula II and Me is methyl, P is preferably acrylate or methacrylate, very preferably methacrylate, and Sp is preferably a single bond.

(88) Very preferred compounds of formula II, IIA, IIB, IIA1-IIA3 and IIB1-IIB5 are selected from the following formulae

(89) ##STR00031## ##STR00032## ##STR00033## ##STR00034##
wherein Me is methyl.

(90) Preferred compounds of formula I, II, IIA, IIB, IIA1-IIA3 and IIB1-IIB5 and their subformulae are selected from the following preferred embodiments, including any combination thereof: a, b, c and d are 0, 1 or 2, preferably 0 or 1, with a+c≥1 and a+b+c+d≤3, a+b+c+d≤4, preferably ≤3, a+b+c+d is 1 or 2, a is 1 or 2 and c is 0, b=d=0, b+d=1, c=d=0, A.sup.1 is straight-chain or branched alkylene with 1 to 20, preferably 1 to 12 C atoms, wherein one or more non-adjacent CH.sub.2-groups are optionally replaced by —CR.sup.0═CR.sup.00—, —C≡C—, —O—, —S—, —CO—, —CO—O—, —O—CO—, —O—CO—O— 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 or Cl, and which is optionally substituted by one or more groups L or P-Sp-, a is 1 and b=c=d=0, Z.sup.1, Z.sup.2, Z.sup.3 and Z.sup.4 are a single bond, A.sup.1 and A.sup.3 are trans-1,4-cyclohexylene, which is optionally substituted by one or more groups L or P-Sp-, A.sup.2 and A.sup.4 are selected from 1,4-phenylene, pyridine and thiophene, all of which are optionally substituted by one or more groups L or P-Sp-, R is P-Sp-, R.sup.1 and R.sup.2 are methyl or methoxy, R.sup.3 is OH, phenyl that is optionally substituted by L or P-Sp-, preferably in para-position, or N-morpholine, i is 3, 4, 5 or 6, preferably 3, g is 1, g is 2 or 3, h is 0, h is 1, p is 1, p is 2, one of p1 and p2 is 0 and the other is 1, p1 is 1 and p2 is 1, All groups P in the compound have the same meaning, the compounds contain exactly two polymerizable groups (represented by P), the compounds contain exactly three polymerizable groups (represented by P), P is selected from the group consisting of acrylate, methacrylate and oxetane, very preferably acrylate or methacrylate, P is methacrylate, all groups Sp are a single bond, at least one of the groups Sp is a single bond and at least one of the groups Sp is different from a single bond, Sp, when being different from a single bond, is —(CH.sub.2).sub.p2—, —(CH.sub.2).sub.p2—O—, —(CH.sub.2).sub.p2—CO—O—, —(CH.sub.2).sub.p2—O—CO—, wherein p2 is 2, 3, 4, 5 or 6, and the O-atom or the CO-group, respectively, is connected to the benzene ring, Sp is a single bond or denotes —(CH.sub.2).sub.p2—, —(CH.sub.2).sub.p2—O—, —(CH.sub.2).sub.p2—CO—O—, —(CH.sub.2).sub.p2—O—CO—, wherein p2 is 2, 3, 4, 5 or 6, and the O-atom or the CO-group, respectively, is connected to the benzene ring, Sp(P).sub.2 is selected from subformulae S11-S31,

(91) 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.

(92) 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.

(93) Compounds with fluoro substituents can be prepared according to or in analogy to the following synthesis scheme.

(94) ##STR00035## ##STR00036##

(95) Further suitable synthesis methods are shown in the examples.

(96) 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.

(97) 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.

(98) 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.

(99) 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.

(100) 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.

(101) 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.

(102) 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.

(103) In another preferred embodiment at least one of the substrates, preferably both substrates, are not equipped with an alignment layer. Preferably the LC medium according to this preferred embodiment contains a self-aligning (SA) additive, preferably in a concentration of 0.1 to 2.5%.

(104) Preferred displays according to this preferred embodiment are SA-VA and SA-FFS displays.

(105) Preferred SA additives for use in this preferred embodiment are selected from compounds comprising a mesogenic group and a straight-chain or branched alkyl side chain that is terminated with one or more polar anchor groups selected from hydroxy, carboxy, amino or thiol groups. Further preferred SA additives contain one or more polymerisable groups which are attached, optionally via spacer groups, to the mesogenic group. These polymerisable SA additives can be polymerised in the LC medium under similar conditions as applied for the RMs in the PSA process.

(106) Suitable SA additives to induce homeotropic alignment, especially for use in SA-VA mode displays, are disclosed for example in US 2013/0182202 A1, US 2014/0838581 A1, US 2015/0166890 A1 and US 2015/0252265 A1.

(107) 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.

(108) 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”).

(109) 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.

(110) The compounds of formula II act as photoinitator which can absorb UV light, especially in the UV-A range, and which can initiate polymerisation of the polymerisable compounds of formula I which show now or only low absorption in the UV-A range.

(111) Due to the presence of polymerisable groups the photoinitiators of formula II can also form a part of the polymer formed by the compounds of formula II.

(112) Thereby the presence of free cleavage products of the photoinitiator in the LC medium after polymerisation is reduced and negative effects on the LC mixture performance parameters, such as VHR, tilt generation or tilt stability are suppressed or even avoided.

(113) In addition to the polymeriabe initiators of formula II, optionally one or more further polymerisation initiators can be 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.

(114) Suitable for free-radical polymerisation are, for example, the commercially available photoinitiators Irgacure651®, Irgacure184®, Irgacure907®, Irgacure369® or Darocurel 173® (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.

(115) In a preferred embodiment of the present invention, the LC medium does not contain any photoinitiator other than those of formula II.

(116) 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.

(117) 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 polymerisation is carried out only in one step (“UV-1 step”) to generate the tilt angle, and a second UV exposure step (“UV-2 step”) to complete polymerisation is not needed and is preferably omitted, the polymerisable LC medium is exposed to UV light in the display generated by a UV lamp emitting radiation in the UV-a range.

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

(119) Preferably the LC medium according to the present invention does essentially consist of a polymerisable component A), or one or more polymerisable compounds of formula I and II, 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.

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

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

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

(123) The LC component B), or LC host mixture, is preferably a nematic LC mixture.

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

(125) 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%.

(126) 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%.

(127) Preferably the proportion of compounds of formula II in the LC medium is from 10 to 500 ppm, very preferably from 50 to 200 ppm.

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

(129) In a preferred embodiment the polymerisable compounds of the polymerisable component B) are exclusively selected from formula I and II.

(130) In another preferred embodiment the polymerisable component B) comprises, in addition to the compounds of formula I and II, one or more further polymerisable compounds (“co-monomers”), preferably selected from RMs.

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

(132) ##STR00037## ##STR00038## ##STR00039## ##STR00040## ##STR00041##
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, and particularly preferably denote —(CH.sub.2).sub.p1—, —(CH.sub.2).sub.p1—O—, —(CH.sub.2).sub.p1—CO—O—, —(CH.sub.2).sub.p1—O—CO— or —(CH.sub.2).sub.p1—O—CO—O—, 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)—, —C≡C—, —N(R.sup.0)—, —O—, —S—, —CO—, —CO—O—, —O—CO—, —O—CO—O— 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 —CO—O—, —O—CO— 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 —CO—O—, —O—CO—, —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 poly-fluorinated 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.

(133) Especially preferred are compounds of formulae M2, M13, M17, M22, M23, M24 and M30.

(134) Further preferred are trireactive compounds M15 to M30, in particular M17, M18, M19, M22, M23, M24, M25, M26, M30 and M31.

(135) In the compounds of formulae M1 to M31 the group

(136) ##STR00042##
is preferably

(137) ##STR00043##
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, ON, 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.

(138) Besides the polymerisable compounds described above, the LC media for use in the LC displays according to the invention comprise an LC mixture (“host mixture”) comprising 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.

(139) 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.

(140) The polymerisable compounds of formula I and II 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 II and of the other polymerisable compounds contained in the LC medium. Compared to RMs known from prior art the compounds of formula I and II do in such an LC host mixture exhibit improved properties, like solubility, reactivity or capability of generating a tilt angle.

(141) Thus, in addition to the polymerisable compounds of formula I and II, 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 and II or of the other polymerisable compounds contained in the LC medium.

(142) 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—, —CO—O—, —O—CO—, —O—CO—O— 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.

(143) 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.

(144) 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%.

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

(146) The mesogenic and LC compounds containing an alkenyl group are preferably selected from formulae AN and AY as defined below.

(147) Besides the polymerisable component A) as described above, the LC media according to the present invention comprise an LC component B), or LC host mixture, comprising one or more, preferably two or more LC compounds which are selected from low-molecular-weight compounds that are unpolymerisable.

(148) 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.

(149) In a first preferred embodiment the LC medium contains an LC component B), or LC host mixture, based on compounds with negative dielectric anisotropy.

(150) 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)-z3) below: a) LC medium wherein the component B) or LC host mixture comprises one or more compounds selected from formulae CY and PY:

(151) ##STR00044## wherein a denotes 1 or 2, b denotes 0 or 1,

(152) ##STR00045##  denotes

(153) ##STR00046## 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—, —CH═CH—, —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—, —CH═CH—, —CF.sub.2O—, —OCF.sub.2—, —CH.sub.2O—, —OCH.sub.2—, —CO—O—, —O—CO—, —C.sub.2F.sub.4—, —CF═CF—, —CH═CH—CH.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.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, 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:

(154) ##STR00047## ##STR00048## ##STR00049## ##STR00050## 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.2═CH—, CH.sub.2═CHCH.sub.2CH.sub.2—, CH.sub.3—CH═CH—, CH.sub.3—CH.sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.3—CH═CH— or CH.sub.3—CH═CH—(CH.sub.2).sub.2—. The compounds of the formula PY are preferably selected from the group consisting of the following sub-formulae:

(155) ##STR00051## ##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, and (O) denotes an oxygen atom or a single bond. Alkenyl preferably denotes CH.sub.2═CH—, CH.sub.2═CHCH.sub.2CH.sub.2—, CH.sub.3—CH═CH—, CH.sub.3—CH.sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.3—CH═CH— or CH.sub.3—CH═CH—(CH.sub.2).sub.2—. b) LC medium wherein the component B) or LC host mixture 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 polymerisable compounds contained in the LC medium. Preferably the component B) or LC host mixture comprises one or more alkenyl compounds selected from formulae AN and AY

(156) ##STR00054## in which the individual radicals, on each occurrence identically or differently, and each, independently of one another, have the following meaning:

(157) ##STR00055## 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—, —CH═CH—, —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—, —CH═CH—, —CF.sub.2O—, —OCF.sub.2—, —CH.sub.2O—, —OCH.sub.2—, —CO—O—, —O—CO—, —C.sub.2F.sub.4—, —CF═CF—, —CH═CH—CH.sub.2O—, or a single bond, preferably a single bond, L.sup.1,2 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. Preferred compounds of formula AN and AY are those wherein R.sup.A2 is selected from ethenyl, propenyl, butenyl, pentenyl, hexenyl and heptenyl. In a preferred embodiment the component B) or LC host mixture comprises one or more compounds of formula AN selected from the following sub-formulae:

(158) ##STR00056## 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.2═CH—, CH.sub.2═CHCH.sub.2CH.sub.2—, CH.sub.3—CH═CH—, CH.sub.3—CH.sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.3—CH═CH— or CH.sub.3—CH═CH—(CH.sub.2).sub.2—. Preferably the the component B) or LC host mixture comprises one or more compounds selected from formulae AN1, AN2, AN3 and AN6, very preferably one or more compounds of formula AN1. In another preferred embodiment the component B) or LC host mixture comprises one or more compounds of formula AN selected from the following sub-formulae:

(159) ##STR00057## 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. In another preferred embodiment the component B) or LC host mixture comprises one or more compounds selected from the following sub-formulae:

(160) ##STR00058## Most preferred are compounds of formula AN1a2 and AN1a5. In another preferred embodiment the component B) or LC host mixture comprises one or more compounds of formula AY selected from the following sub-formulae:

(161) ##STR00059## ##STR00060## ##STR00061## ##STR00062## in which alkyl and alkyl* each, independently of one another, denote a straight-chain alkyl radical having 1-6 C atoms, “(O)” denotes an O-atom or a single bond, 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.2═CH—, CH.sub.2═CHCH.sub.2CH.sub.2—, CH.sub.3—CH═CH—, CH.sub.3—CH.sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.3—CH═CH— or CH.sub.3—CH═CH—(CH.sub.2).sub.2—. In another preferred embodiment the component B) or LC host mixture comprises one or more compounds of formula AY selected from the following sub-formulae:

(162) ##STR00063## in which m and n each, independently of one another, denote 1, 2, 3, 4, 5 or 6, and alkenyl denotes CH.sub.2═CH—, CH.sub.2═CHCH.sub.2CH.sub.2—, CH.sub.3—CH═CH—, CH.sub.3—CH.sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.3—CH═CH— or CH.sub.3—CH═CH—(CH.sub.2).sub.2—. Preferably the proportion of compounds of formula AN and AY in the LC medium is from 2 to 70% by weight, very preferably from 5 to 60% by weight, most preferably from 10 to 50% by weight. Preferably the LC medium or LC host mixture contains 1 to 5, preferably 1, 2 or 3 compounds selected from formulae AN and AY. In another preferred embodiment of the present invention the LC medium comprises one or more compounds of formula AY14, very preferably of AY14a. The proportion of compounds of formula AY14 or AY14a in the LC medium is preferably 3 to 20% by weight. The addition of alkenyl compounds of formula AN and/or AY enables a reduction of the viscosity and response time of the LC medium. c) LC medium wherein the component B) or LC host mixture comprises one or more compounds of the following formula:

(163) ##STR00064## in which the individual radicals have the following meanings:

(164) ##STR00065##  denotes

(165) ##STR00066##  denotes

(166) ##STR00067## 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—, —CH═CH—, —CO—, —O—CO— or —CO—O— in such a way that O atoms are not linked directly to one another, Z.sup.y denotes —CH.sub.2CH.sub.2—, —CH═CH—, —CF.sub.2O—, —OCF.sub.2—, —CH.sub.2O—, —OCH.sub.2—, —CO—O—, —O—CO—, —C.sub.2F.sub.4—, —CF═CF—, —CH═CH—CH.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:

(167) ##STR00068## 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.2═CH—, CH.sub.2═CHCH.sub.2CH.sub.2—, CH.sub.3—CH═CH—, CH.sub.3—CH.sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.3—CH═CH— or CH.sub.3—CH═CH—(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:

(168) ##STR00069## wherein the propyl, butyl and pentyl groups are straight-chain groups. Most preferred are compounds of formula ZK1a. d) LC medium wherein component B) or the LC host mixture additionally comprises one or more compounds of the following formula:

(169) ##STR00070## 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—, —CH═CH—, —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,

(170) ##STR00071##  denotes

(171) ##STR00072##  denotes

(172) ##STR00073##  and e denotes 1 or 2. The compounds of the formula DK are preferably selected from the group consisting of the following sub-formulae:

(173) ##STR00074## 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.2═CH—, CH.sub.2═CHCH.sub.2CH.sub.2—, CH.sub.3—CH═CH—, CH.sub.3—CH.sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.3—CH═CH— or CH.sub.3—CH═CH—(CH.sub.2).sub.2—. e) LC medium wherein component B) or the LC host mixture additionally comprises one or more compounds of the following formula:

(174) ##STR00075## in which the individual radicals have the following meanings:

(175) ##STR00076##  denotes

(176) ##STR00077## 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—, —CH═CH—, —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—, —CH═CH—, —CF.sub.2O—, —OCF.sub.2—, —CH.sub.2O—, —OCH.sub.2—, —CO—O—, —O—CO—, —C.sub.2F.sub.4—, —CF═CF—, —CH═CH—CH.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:

(177) ##STR00078## ##STR00079## ##STR00080## 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.2═CH—, CH.sub.2═CHCH.sub.2CH.sub.2—, CH.sub.3—CH═CH—, CH.sub.3—CH.sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.3—CH═CH— or CH.sub.3—CH═CH—(CH.sub.2).sub.2—. f) LC medium wherein component B) or the LC host mixture additionally comprises one or more compounds selected from the group consisting of the following formulae:

(178) ##STR00081## 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 OCH═CF.sub.2. Particular preference is given to compounds of the formula G1 in which X denotes F. g) LC medium wherein component B) or the LC host mixture additionally comprises one or more compounds selected from the group consisting of the following formulae:

(179) ##STR00082## ##STR00083## 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. h) LC medium wherein component B) or the LC host mixture additionally comprises one or more biphenyl compounds selected from the group consisting of the following formulae:

(180) ##STR00084## 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.2═CH—, CH.sub.2═CHCH.sub.2CH.sub.2—, CH.sub.3—CH═CH—, CH.sub.3—CH.sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.3—CH═CH— or CH.sub.3—CH═CH—(CH.sub.2).sub.2—. The proportion of the biphenyls of the formulae B1 to B3 in the LC host 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:

(181) ##STR00085## 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. i) LC medium wherein component B) or the LC host mixture additionally comprises one or more terphenyl compounds of the following formula:

(182) ##STR00086## in which R.sup.5 and R.sup.6 each, independently of one another, have one of the meanings indicated above, and

(183) ##STR00087## each, independently of one another, denote

(184) ##STR00088## 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:

(185) ##STR00089## ##STR00090## ##STR00091## 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.2═CH—, CH.sub.2═CHCH.sub.2CH.sub.2—, CH.sub.3—CH═CH—, CH.sub.3—CH.sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.3—CH═CH— or CH.sub.3—CH═CH—(CH.sub.2).sub.2—. R preferably denotes methyl, ethyl, propyl, butyl, pentyl, hexyl, methoxy, ethoxy, propoxy, butoxy or pentoxy. The LC host mixture 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 LC media according to the invention if the Δn value of the mixture is to be ≥0.1. Preferred LC media 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. k) LC medium wherein component B) or the LC host mixture additionally comprises one or more quaterphenyl compounds selected from the group consisting of the following formulae:

(186) ##STR00092## 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

(187) ##STR00093## 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 host mixture 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 host mixture contains 1 to 5, preferably 1 or 2 compounds of formula Q. The addition of quaterphenyl compounds of formula Q to the LC host 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 ε.sub.∥ and ε.sub.⊥ and in particular enables to achieve a high value of the dielectric constant ε.sub.∥ while keeping the dielectric anisotropy Δε constant, thereby reducing the kick-back voltage and reducing image sticking. I) LC medium wherein component B) or the LC host mixture additionally comprises one or more compounds of formula C:

(188) ##STR00094## wherein R.sup.C denotes 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.C denotes 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.C1, L.sup.C2 independently of each other denote H or F, with at least one of L.sup.C1 and L.sup.C2 being F. Preferred compounds of formula C are those wherein R.sup.C denotes straight-chain alkyl with 2 to 6 C-atoms, very preferably ethyl, n-propyl or n-butyl. Preferred compounds of formula C are those wherein L.sup.C1 and L.sup.C2 are F. Preferred compounds of formula C are those wherein X.sup.C denotes F or OCF.sub.3, very preferably F. Preferred compounds of formula C are selected from the following formula

(189) ##STR00095## wherein R.sup.C has one of the meanings of formula C or one of its preferred meanings given above and below, and is preferably ethyl, n-propyl or n-butyl, very preferably n-propyl. Preferably the proportion of compounds of formula C in the LC host mixture is from >0 to ≤10% by weight, very preferably from 0.1 to 8% by weight, most preferably from 0.2 to 5% by weight. Preferably the LC host mixture contains 1 to 5, preferably 1, 2 or 3 compounds of formula C. The addition of compounds of formula C, which have positive dielectric anisotropy, to the LC medium with negative dielectric anisotropy allows a better control of the values of the dielectric constants ε.sub.∥ and ε.sub.⊥, and in particular enables to achieve a high value of the dielectric constant ε.sub.∥ while keeping the dielectric anisotropy Δε constant, thereby reducing the kick-back voltage and reducing image sticking. Besides, the addition of compounds of formula C enables to reduce the viscosity and the response time of the LC medium. m) LC medium wherein component B) or the LC host mixture additionally comprises one or more compounds selected from the group consisting of the following formulae:

(190) ##STR00096## 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. n) LC medium wherein component B) or the LC host mixture additionally comprises one or more compounds of the following formula:

(191) ##STR00097## in which

(192) ##STR00098##  denotes

(193) ##STR00099## 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:

(194) ##STR00100## 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 FI1, FI2 and FI3. o) LC medium wherein component B) or the LC host mixture additionally comprises one or more compounds selected from the group consisting of the following formulae:

(195) ##STR00101## 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. p) LC medium wherein component B) or the LC host mixture 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:

(196) ##STR00102## ##STR00103## 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—, —CH═CH—, —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—, —CH═CH—, —(CH.sub.2).sub.4—, —(CH.sub.2).sub.30—, —O(CH.sub.2).sub.3—, —CH═CH—CH.sub.2CH.sub.2—, —CH.sub.2CH.sub.2CH═CH—, —CH.sub.2O—, —OCH.sub.2—, —CO—O—, —O—CO—, —C.sub.2F.sub.4—, —CF═CF—, —CF═CH—, —CH═CF—, —CH.sub.2— or a single bond. q) LC medium wherein component B) or the LC host mixture additionally comprises one or more difluorodibenzochromans and/or chromans of the following formulae:

(197) ##STR00104## 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—, —CO—O— or —O—CO—, c is O, 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:

(198) ##STR00105## ##STR00106## ##STR00107## 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.2═CH—, CH.sub.2═CHCH.sub.2CH.sub.2—, CH.sub.3—CH═CH—, CH.sub.3—CH.sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.3—CH═CH— or CH.sub.3—CH═CH—(CH.sub.2).sub.2—. Very particular preference is given to LC host mixtures comprising one, two or three compounds of the formula BC-2. r) LC medium wherein component B) or the LC host mixture additionally comprises one or more fluorinated phenanthrenes and/or dibenzofurans of the following formulae:

(199) ##STR00108## 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.

(200) Particularly preferred compounds of the formulae PH and BF are selected from the group consisting of the following sub-formulae:

(201) ##STR00109## in which R and R′ each, independently of one another, denote a straight-chain alkyl or alkoxy radical having 1-7 C atoms. s) LC medium wherein component B) or the LC host mixture additionally comprises one or more monocyclic compounds of the following formula

(202) ##STR00110## 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—, —CH═CH—, —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:

(203) ##STR00111## 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.2═CH—, CH.sub.2═CHCH.sub.2CH.sub.2—, CH.sub.3—CH═CH—, CH.sub.3—CH.sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.3—CH═CH— or CH.sub.3—CH═CH—(CH.sub.2).sub.2—. Particularly preferred compounds of the formula Y are selected from the group consisting of the following sub-formulae:

(204) ##STR00112## wherein Alkoxy preferably denotes straight-chain alkoxy with 3, 4, or 5 C atoms. t) LC medium which, apart from the polymerisable compounds as described above and below, does not contain a compound which contains a terminal vinyloxy group (—O—CH═CH.sub.2). u) LC medium wherein component B) or the LC host mixture 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 LC host 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 wherein component B) or the LC host mixture 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 LC host 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 wherein component B) or the LC host mixture 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 LC host 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 LC host 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 formulae AN and AY, very preferably selected from formulae AN1, AN3, AN6 and AY14, most preferably from formulae AN1a, AN3a, AN6a and AY14. 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 wherein component B) or the LC host mixture 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 LC host 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 wherein component B) or the LC host mixture contains one or more, preferably 1, 2 or 3, compounds selected from formulae T1, T2 and T5, very preferably from formula T2. The content of these compounds in the LC host mixture as a whole is preferably 1 to 20%. z2) LC medium in which the LC host mixture contains one or more compounds selected from formulae CY and PY, one or more compounds selected from formulae AN and AY, and one or more compounds selected from formulae T and Q. z3) 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%.

(205) 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.

(206) ##STR00113##
in which the individual radicals have, independently of each other and on each occurrence identically or differently, the following meanings:

(207) ##STR00114##
each, independently of one another, and on each occurrence, identically or differently

(208) ##STR00115## R.sup.21, R.sup.31 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-CH═CH—, trans-CF═CF—, —CH.sub.2O— or a single bond, preferably —CH.sub.2CH.sub.2—, —COO—, trans-CH═CH— or a single bond, particularly preferably —COO—, trans-CH═CH— or a single bond, L.sup.21, L.sup.22, L.sup.31, L.sup.32 each, independently of one another, H or F, g 0, 1, 2 or 3.

(209) In the compounds of formula A and B, 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 CH═CF.sub.2, very preferably F or OCF.sub.3, most preferably F.

(210) In the compounds of formula A and B, R.sup.21 and R.sup.31 are preferably selected from straight-chain alkyl or alkoxy with 1, 2, 3, 4, 5 or 6 C atoms, and straight-chain alkenyl with 2, 3, 4, 5, 6 or 7 C atoms.

(211) In the compounds of formula A and B, g is preferably 1 or 2.

(212) In the compounds of formula B, Z.sup.31 is preferably COO, trans-CH═CH or a single bond, very preferably COO or a single bond.

(213) Preferably component B) of the LC medium comprises one or more compounds of formula A selected from the group consisting of the following formulae:

(214) ##STR00116##
in which A.sup.21, R.sup.21, X.sup.0, L.sup.21 and L.sup.22 have the meanings given in formula A, 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 A1 and A2.

(215) Particularly preferred compounds of formula A1 are selected from the group consisting of the following subformulae:

(216) ##STR00117##
in which R.sup.21, X.sup.0, L.sup.21 and L.sup.22 have the meaning given in formula A1, 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.

(217) Very particularly preferred compounds of formula A1 are selected from the group consisting of the following subformulae:

(218) ##STR00118##
In which R.sup.21 is as defined in formula A1.

(219) Particularly preferred compounds of formula A2 are selected from the group consisting of the following subformulae:

(220) ##STR00119## ##STR00120##
in which R.sup.21, X.sup.0, L.sup.21 and L.sup.22 have the meaning given in formula A2, 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.

(221) Very particularly preferred compounds of formula A2 are selected from the group consisting of the following subformulae:

(222) ##STR00121## ##STR00122##
in which R.sup.21 and X.sup.0 are as defined in formula A2.

(223) Particularly preferred compounds of formula A3 are selected from the group consisting of the following subformulae:

(224) ##STR00123##
in which R.sup.21, X.sup.0, L.sup.21 and L.sup.22 have the meaning given in formula A3, and X.sup.0 is preferably F.

(225) Particularly preferred compounds of formula A4 are selected from the group consisting of the following subformulae:

(226) ##STR00124##
in which R.sup.21 is as defined in formula A4.

(227) Preferably component B) of the LC medium comprises one or more compounds of formula B selected from the group consisting of the following formulae:

(228) ##STR00125##
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 B, and X.sup.0 is preferably F. Particularly preferred are compounds of formulae B1 and B2.

(229) Particularly preferred compounds of formula B1 are selected from the group consisting of the following subformulae:

(230) ##STR00126##
in which R.sup.31, X.sup.0, L.sup.31 and L.sup.32 have the meaning given in formula B1, and X.sup.0 is preferably F.

(231) Very particularly preferred compounds of formula B1a are selected from the group consisting of the following subformulae:

(232) ##STR00127##
in which R.sup.31 is as defined in formula B1.

(233) Very particularly preferred compounds of formula B1b are selected from the group consisting of the following subformulae:

(234) ##STR00128##
in which R.sup.31 is as defined in formula B1.

(235) Particularly preferred compounds of formula B2 are selected from the group consisting of the following subformulae:

(236) ##STR00129## ##STR00130##
in which R.sup.31, X.sup.0, L.sup.31 and L.sup.32 have the meaning given in formula B2, L.sup.33, 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.

(237) Very particularly preferred compounds of formula B2 are selected from the group consisting of the following subformulae:

(238) ##STR00131##
in which R.sup.31 is as defined in formula B2.

(239) Very particularly preferred compounds of formula B2b are selected from the group consisting of the following subformulae

(240) ##STR00132##
in which R.sup.31 is as defined in formula B2.

(241) Very particularly preferred compounds of formula B2c are selected from the group consisting of the following subformulae:

(242) ##STR00133##
in which R.sup.31 is as defined in formula B2.

(243) Very particularly preferred compounds of formula B2d and B2e are selected from the group consisting of the following subformulae:

(244) ##STR00134##
in which R.sup.31 is as defined in formula B2.

(245) Very particularly preferred compounds of formula B2f are selected from the group consisting of the following subformulae:

(246) ##STR00135##
in which R.sup.31 is as defined in formula B2.

(247) Very particularly preferred compounds of formula B2g are selected from the group consisting of the following subformulae:

(248) ##STR00136##
in which R.sup.31 is as defined in formula B2.

(249) Very particularly preferred compounds of formula B2h are selected from the group consisting of the following subformulae:

(250) ##STR00137##
in which R.sup.31 is as defined in formula B2.

(251) Very particularly preferred compounds of formula B2i are selected from the group consisting of the following subformulae:

(252) ##STR00138##
in which R.sup.31 is as defined in formula B2.

(253) Very particularly preferred compounds of formula B2k are selected from the group consisting of the following subformulae:

(254) ##STR00139##
in which R.sup.31 is as defined in formula B2.

(255) Very particularly preferred compounds of formula B21 are selected from the group consisting of the following subformulae:

(256) ##STR00140##
in which R.sup.31 is as defined in formula B2.

(257) Alternatively to, or in addition to, the compounds of formula B1 and/or B2 component B) of the LC medium may also comprise one or more compounds of formula B3 as defined above.

(258) Particularly preferred compounds of formula B3 are selected from the group consisting of the following subformulae:

(259) ##STR00141##
in which R.sup.31 is as defined in formula B3.

(260) Preferably component B) of the LC medium comprises, in addition to the compounds of formula A and/or B, one or more compounds of formula C

(261) ##STR00142##
in which the individual radicals have the following meanings:

(262) ##STR00143##
each, independently of one another, and on each occurrence, identically or differently

(263) ##STR00144## 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, Z.sup.41, Z.sup.42 each, independently of one another, —CH.sub.2CH.sub.2—, —COO—, trans-CH═CH—, trans-CF═CF—, —CH.sub.2O—, —CF.sub.2O—, —C≡C— or a single bond, preferably a single bond, h 0, 1, 2 or 3.

(264) In the compounds of formula C, R.sup.41 and R.sup.42 are preferably selected from straight-chain alkyl or alkoxy with 1, 2, 3, 4, 5 or 6 C atoms, and straight-chain alkenyl with 2, 3, 4, 5, 6 or 7 C atoms.

(265) In the compounds of formula C, h is preferably 0, 1 or 2.

(266) In the compounds of formula C, Z.sup.41 and Z.sup.42 are preferably selected from COO, trans-CH═CH and a single bond, very preferably from COO and a single bond.

(267) Preferred compounds of formula C are selected from the group consisting of the following subformulae:

(268) ##STR00145## ##STR00146##
wherein R.sup.41 and R.sup.42 have the meanings given in formula C, 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.

(269) Further preferably component B) of the LC medium comprises, in addition to the compounds of formula A and/or B, one or more compounds of formula D

(270) ##STR00147##
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 C or one of the preferred meanings given above.

(271) Preferred compounds of formula D are selected from the group consisting of the following subformulae:

(272) ##STR00148##
in which R.sup.41 and R.sup.42 have the meanings given in formula D and R.sup.41 preferably denotes alkyl bedeutet, and in formula D1 R.sup.42 preferably denotes alkenyl, particularly preferably —(CH.sub.2).sub.2—CH═CH—CH.sub.3, and in formula D2 R.sup.42 preferably denotes alkyl, —(CH.sub.2).sub.2—CH═CH.sub.2 or —(CH.sub.2).sub.2—CH═CH—CH.sub.3.

(273) Further preferably component B) of the LC medium comprises, in addition to the compounds of formula A and/or B, one or more compounds of formula E containing an alkenyl group

(274) ##STR00149##
in which the individual radicals, on each occurrence identically or differently, each, independently of one another, have the following meaning:

(275) ##STR00150## 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—, —CH═CH—, —CO—, —OCO— or —COO— in such a way that O atoms are not linked directly to one another, x 1 or 2.

(276) 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.

(277) Preferred compounds of formula E are selected from the following sub-formulae:

(278) ##STR00151##
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.2═CH—, CH.sub.2═CHCH.sub.2CH.sub.2—, CH.sub.3—CH═CH—, CH.sub.3—CH.sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.2—CH═CH—, CH.sub.3—(CH.sub.2).sub.3—CH═CH— or CH.sub.3—CH═CH—(CH.sub.2).sub.2—.

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

(280) ##STR00152##
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.

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

(282) ##STR00153##

(283) Most preferred are compounds of formula E1a2, E1a5, E3a1 and E6a1.

(284) Further preferably component B) of the LC medium comprises, in addition to the compounds of formula A and/or B, one or more compounds of formula F

(285) ##STR00154##
in which the individual radicals have, independently of each other and on each occurrence identically or differently, the following meanings:

(286) ##STR00155##

(287) ##STR00156## R.sup.21, R.sup.31 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.21 —CH.sub.2CH.sub.2—, —CF.sub.2CF.sub.2—, —COO—, trans-CH═CH—, trans-CF═CF—, —CH.sub.2O— or a single bond, preferably —CH.sub.2CH.sub.2—, —COO—, trans-CH═CH— or a single bond, particularly preferably —COO—, trans-CH═CH— or a single bond, L.sup.21, L.sup.22, L.sup.23, L.sup.24 each, independently of one another, H or F, g 0, 1, 2 or 3.

(288) Particularly preferred compounds of formula F are selected from the group consisting of the following formulae:

(289) ##STR00157##
in which R.sup.21, X.sup.0, L.sup.21 and L.sup.22 have the meaning given in formula F, L.sup.25 and L.sup.26 are each, independently of one another, H or F, and X.sup.0 is preferably F.

(290) Very particularly preferred compounds of formula F.sub.1-F.sub.3 are selected from the group consisting of the following subformulae:

(291) ##STR00158##
In which R.sup.21 is as defined in formula F.sub.1.

(292) The concentration of the compounds of formula A and B in the LC host mixture is preferably from 2 to 60%, very preferably from 3 to 45%, most preferably from 4 to 35%.

(293) The concentration of the compounds of formula C and D in the LC host mixture is preferably from 2 to 70%, very preferably from 5 to 65%, most preferably from 10 to 60%.

(294) The concentration of the compounds of formula E in the LC host mixture is preferably from 5 to 50%, very preferably from 5 to 35%.

(295) The concentration of the compounds of formula F in the LC host mixture is preferably from 2 to 30%, very preferably from 5 to 20%.

(296) Further preferred embodiments of this second preferred embodiment of the present invention are listed below, including any combination thereof. 2a) The LC host mixture comprises one or more compounds of formula A and/or B with high positive dielectric anisotropy, preferably with Δε>15. 2b) The LC host mixture comprises one or more compounds selected from the group consisting of formulae A1a2, A1b1, A1d1, A1f1, A2a1, A2h1, A2l2, A2k1, B2h3, B2l1, F1a. The proportion of these compounds in the LC host mixture is preferably from 4 to 40%, very preferably from 5 to 35%. 2c) The LC host mixture comprises one or more compounds selected from the group consisting of formulae B2c1, B2c4, B2f4, C14. The proportion of these compounds in the LC host mixture is preferably from 4 to 40%, very preferably from 5 to 35%. 2d) The LC host mixture comprises one or more compounds selected from the group consisting of formulae C3, C4, C5, C9 and D2. The proportion of these compounds in the LC host mixture is preferably from 8 to 70%, very preferably from 10 to 60%. 2e) The LC host mixture comprises one or more compounds selected from the group consisting of formulae G1, G2 and G5, preferably G1a, G2a and G5a. The proportion of these compounds in the LC host mixture is preferably from 4 to 40%, very preferably from 5 to 35%. 2f) The LC host mixture comprises one or more compounds selected from the group consisting of formulae E1, E3 and E6, preferably E1a, E3a and E6a, very preferably E1a2, E1a5, E3a1 and E6a1. The proportion of these compounds in the LC host mixture is preferably from 5 to 60%, very preferably from 10 to 50%.

(297) 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.

(298) 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.

(299) 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 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.

(300) 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 Δε, preferably from −0.5 to −10, in particular from −2.5 to −7.5, at 20° C. and 1 kHz.

(301) The birefringence Δn 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.

(302) 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.

(303) 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 Δε from +4 to +17 at 20° C. and 1 kHz.

(304) The birefringence Δn 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.

(305) The birefringence Δn 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.

(306) 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 Δε from +2 to +30, particularly preferably from +3 to +20, at 20° C. and 1 kHz.

(307) 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).

(308) 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.

(309) 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.

(310) 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, tetrabutylammonium 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.

(311) 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.

(312) 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.

(313) 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.

(314) 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.

(315) Preferred mixture components are shown in Tables A1 and A2 below. The compounds shown in Table A1 are especially suitable for use in LC mixtures with positive dielectric anisotropy. The compounds shown in Table A2 are especially suitable for use in LC mixtures with negative dielectric anisotropy.

(316) TABLE-US-00001 TABLE A1 In Table A1, m and n are independently of each other an integer from 1 to 12, preferably 1, 2, 3, 4, 5 or 6, k is 0, 1, 2, 3, 4, 5 or 6, and (O)C.sub.mH.sub.2m+1 means C.sub.mH.sub.2m+1 or OC.sub.mH.sub.2m+1. APU-n-OXF 0 ACQU-n-F APUQU-n-F BCH-nF.F BCH-nF.F.F BCH-n.Fm CFU-n-F CBC-nm CBC-nmF CCOC-n-m C-n-V 0 C-n-XF C-n-m CC-n-V CC-n-Vm CC-n-kVm CC-nV-Vm CCP-nV-m CCP-Vn-m CCG-V-F CCVC-n-V 0 CCP-n-m CP-nV-m CP-Vn-m CPPC-nV-Vm CVCP-1V-OT CLP-n-T CLP-n-OT CLP-nV-T CLP-nV-OT CLP-Vn-T 0 CLP-Vn-OT CLP-nVm-T CLP-nVm-OT CLP-nVk-m CPGP-n-m CCP-n0CF.sub.3 CCP-nF.F.F CGG-n-F CGU-n-F CDU-n-F 00 DCU-n-F 01 CCGU-n-F 02 CPGU-n-F 03 CCPU-n-F 04 CPGU-n-OT 05 CCQU-n-F 06 CCQG-n-F 07 CUQU-n-F 08 CQU-n-F 09 CCCQU-n-F 0 CDUQU-n-F CLUQU-n-F CPPQU-n-F CGUQU-n-F CCZU-m-F CGZP-n-OT CPTU-n-F GPTU-n-F CPU-n-VT CPU-n-AT 0 CPU-n-OXF CWCG-n-F CWCU-n-F CWCQU-n-F Dec-U-n-F LPP-n-m DPGU-n-F DPGU-n-OT DGUQU-n-F DUUQU-n-F 0 ECCP-nm ECCP-nOCF.sub.3 GP-n-CI GGP-n-CI GGP-n-F PGIGI-n-F GPQU-n-F GUQGU-n-F PGU-n-OXF MPP-n-F 0 MUQU-n-F NUQU-n-F PGU-n-F PPGU-n-F PQU-n-F PUQU-n-F PGUQU-n-F PGP-n-m PGP-n-kVm PP-nV-Vm 0 PP-n-kVm PCH-nOm PCH-nCl PYP-nF

(317) TABLE-US-00002 TABLE 2A In Table A2, m and n are independently of each other an integer from 1 to 12, preferably 1, 2, 3, 4, 5 or 6, k is 0, 1, 2, 3, 4, 5 or 6, and (O)C.sub.mH.sub.2m+1 means C.sub.mH.sub.2m+1 or OC.sub.mH.sub.2m+1.   AIK-n-F   AIY-n-Om   AY-n-Om   B-nO-Om   B-n-Om   B-nO-O5i 0   B(S)-nO-Om   CB-n-m   CB-n-Om   PB-n-m   PB-n-Om   BCH-nm   BCH-nmF   BCN-nm   C-1V-V1   CY-n-Om 0   CY(F, Cl)-n-Om   CY(Cl, F)-n-Om   CCY-n-Om   CCY(F, Cl)-n-Om   CCY(Cl, F)-n-Om   CCY-n-m   CCY-V-m   CCY-Vn-m   CCY-n-OmV   CBC-nmF 0   CBC-nm   CCP-V-m   CCP-Vn-m   CCP-nV-m   CCP-n-m   CPYP-n-(O)m   CYYC-n-m   CCYY-n-(O)m   CCY-n-O2V   CCH-nOm 0   CCC-n-m   CCC-n-V   CY-n-m   CCH-nm   CC-n-V   CC-n-V1   CC-n-Vm   CC-V-V   CC-V-V1   CC-2V-V2 00   CVC-n-m 01   CC-n-mV 02   CCOC-n-m 03   CP-nOmFF 04   CH-nm 05   CEY-n-Om 06   CEY-V-n 07   CVY-V-n 08   CY-V-On 09   CY-n-O1V 0   CY-n-OC(CH.sub.3)═CH.sub.2   CCN-nm   CY-n-OV   CCPC-nm   CCY-n-kOm   CPY-n-Om   CPY-n-m   CPY-V-Om   CQY-n-(O)m   CQIY-n-(O)m 0   CCQY-n-(O)m   CCQIY-n-(O)m   CPQY-n-(O)m   CPQIY-n-(O)m   CPYG-n-(O)m   CCY-V-Om   CCY-V2-(O)m   CCY-1V2-(O)m   CCY-3V-(O)m   CCVC-n-V 0   CCVC-V-V   CPYG-n-(O)m   CPGP-n-m   CY-nV-(O)m   CENaph-n-Om   COChrome-n-Om   COChrome-n-m   CCOChrome-n-Om   CCOChrome-n-m   CONaph-n-Om 0   CCONaph-n-Om   CCNaph-n-Om   CNaph-n-Om   CETNaph-n-Om   CTNaph-n-Om   CK-n-F   CLY-n-Om   CLY-n-m   LYLI-n-m   CYLI-n-m 0   LY-n-(O)m   COYOICC-n-m   COYOIC-n-V   CCOY-V-O2V   CCOY-V-O3V   COY-n-Om   CCOY-n-Om   D-nOmFF   PCH-nm   PCH-nOm 0   PGIGI-n-F   PGP-n-m   PP-n-m   PP-n-2V1   PYP-n-mV   PYP-n-m   PGIY-n-Om   PYP-n-Om   PPYY-n-m   PPGU-n-F 0   YPY-n-m   YPY-n-mV   PY-n-Om   PY-n-m   PY-V2-Om   DFDBC-n(O)-(O)m   Y-nO-Om   Y-nO-OmV   Y-nO-OkVm   YG-n-OM 0   YG-nO-Om   YGI-n-Om   YGI-nO-Om   YY-n-Om   YY-nO-Om

(318) In a first preferred embodiment of the present invention, the LC media according to the invention, especially those with positive dielectric anisotropy, comprise one or more compounds selected from the group consisting of compounds from Table A1.

(319) In a second preferred embodiment of the present invention, the LC media according to the invention, especially those with negative dielectric anisotropy, comprise one or more compounds selected from the group consisting of compounds from Table A2.

(320) TABLE-US-00003 TABLE B Table B shows possible chiral dopants which can be added to the LC media according to the invention. C 15 CB 15 CM 21 R/S-811 CM 44 0 CM 45 CM 47 CN R/S-2011 R/S-3011 R/S-4011 R/S-5011 R/S-1011

(321) 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.

(322) TABLE-US-00004 TABLE C Table C shows possible stabilisers which can be added to the LC media according to the invention. Therein n denotes an integer from 1 to 12, preferably 1, 2, 3, 4, 5, 6, 7 or 8, and terminal methyl groups are not shown. 00 01 02 03 04 05 06 07 08 09 0 0 0 0

(323) 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.

(324) TABLE-US-00005 TABLE D Table D shows illustrative reactive mesogenic compounds which can be used in the LC media in accordance with the present invention. RM-1 RM-2 RM-3 RM-4 0 RM-5 RM-6 RM-7 RM-8 RM-9 RM-10 RM-11 RM-12 RM-13 RM-14 0 RM-15 RM-16 RM-17 RM-18 RM-19 RM-20 RM-21 RM-22 RM-23 RM-24 0 RM-25 RM-26 RM-27 RM-28 RM-29 RM-30 RM-31 RM-32 RM-33 RM-34 0 RM-35 RM-36 RM-37 RM-38 RM-39 RM-40 RM-41 RM-42 RM-43 RM-44 0 RM-45 RM-46 RM-47 RM-48 RM-49 RM-50 RM-51 RM-52 RM-53 RM-54 00 RM-55 01 RM-56 02 RM-57 03 RM-58 04 RM-59 05 RM-60 06 RM-61 07 RM-62 08 RM-63 09 RM-64 0 RM-65 RM-66 RM-67 RM-68 RM-69 RM-70 RM-71 RM-72 RM-73 RM-74 0 RM-75 RM-76 RM-77 RM-78 RM-79 RM-80 RM-81 RM-82 RM-83 RM-84 0 RM-85 RM-86 RM-87 RM-88 RM-89 RM-90 RM-91 RM-92 RM-93 RM-94 0 RM-95 RM-96 RM-97 RM-98 RM-99 RM-100 RM-101 RM-102 RM-103 RM-104 0 RM-105 RM-106 RM-107 RM-108 RM-109 RM-110 RM-111 RM-112 RM-113 RM-114 0 RM-115 RM-116 RM-117 RM-118 RM-119 RM-120 RM-121 RM-122 RM-123 RM-124 0 RM-125 RM-126 RM-127 RM-128 RM-129 RM-130 RM-131

(325) In a preferred embodiment, the mixtures according to the invention comprise one or more polymerisable compounds, preferably selected from the polymerisable compounds of the formulae RM-1 to RM-131. Of these, compounds RM-1, RM-4, RM-8, RM-17, RM-19, RM-35, RM-37, RM-43, RM-47, RM-49, RM-51, RM-59, RM-69, RM-71, RM-83, RM-97, RM-98, RM-104, RM-112, RM-115 and RM-116 are particularly preferred.

EXAMPLES

(326) 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.

(327) 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, Δn optical anisotropy at 20° C. and 589 nm, ε⊥ dielectric permittivity perpendicular to the director at 20° C. and 1 kHz, ε∥ dielectric permittivity parallel to the director at 20° C. and 1 kHz, Δε dielectric anisotropy at 20° C. and 1 kHz, cl.p., T(N,I) clearing point [° C.], γ.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].

(328) 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.

(329) 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.

(330) 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 Δn is determined at 589 nm and Δε at 1 kHz, unless explicitly indicated otherwise in each case.

(331) 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).

(332) 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.

(333) 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.

(334) The display used for measurement of the capacitive threshold voltage consists of two plane-parallel glass outer plates at a separation of 25 μm, 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.

(335) 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 μm, 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.

(336) The polymerisable compounds are polymerised in the display or test cell by irradiation with UV 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.

(337) The intensity is measured using a standard meter (Hoenle UV-meter high end with UV sensor).

(338) The tilt angle is determined using the Mueller Matrix Polarimeter “AxoScan” from Axometrics. A low value (i.e. a large deviation from the 90° angle) corresponds to a large tilt here.

(339) Unless stated otherwise, the term “tilt angle” means the angle between the LC director and the substrate, and “LC director” means in a layer of LC molecules with uniform orientation the preferred orientation direction of the optical main axis of the LC molecules, which corresponds, in case of calamitic, uniaxially positive birefringent LC molecules, to their molecular long axis.

Example 1: Polymerisable Compound of Formula I

(340) Polymerisable compound RM1 is prepared as follows

(341) ##STR00577##

(342) RM1: Methacrylic acid (9.98 g, 116.0 mmol) and 4-(dimethylamino)pyridine (0.616 g, 5.04 mmol) is added to a suspension of bicycloheyl-4,4′-diol (10.0 g, 50.4 mmol) in 150 ml DCM. The reaction mixture is treated dropwise at 0° C. with a solution of N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide (18.02 g, 116.0 mmol) in 50 ml DCM and stirred for 20 hrs at room temperature. The reaction mixture is concentrated in vacuo, and the oily residue is purified by column chromatography on silica gel with DCM as eluent and further recrystallized from acetonitrile to afford RM1 as white crystal (4.50 g, m.p. 114° C.).

(343) The following compounds were prepared analogously:

(344) ##STR00578##

Example 2: Polymerisable Photoinitiator of Formula II

(345) Polymerisable photoinitiator PIn-1 is prepared as follows

(346) ##STR00579##

(347) PIn-1a: To a solution of 4-hydroxylphenylboronic acid pinacol ester (50.0 g, 0.23 mol) in 320 ml dry dichloromethane (DCM) trimethylamine (37.8 ml, 0.27 mol) and 4-(dimethylamino)-pyridine (1.47 g, 12.0 mmol) are added at 0° C. A solution of chlorotriisopropylsilane (53.5 ml, 0.25 mol) in 80 ml dry DCM is added carefully at below 5° C. The reaction mixture is then allowed to warmed up to RT and stirred overnight. After aqueous work-up, the crude product is purified by column chromatography on silica gel with DCM as eluent to afford PIn-1a as colorless oil (76.2 g).

(348) PIn-1b: To a solution of PIn-1a (16.56 g, 44.0 mmol) and 1-(3-bromo-phenyl)-2-methyl-propan-1-one (10.0 g, 44.0 mmol) in 160 ml THF is added the solution of sodium metaborate tetrahydrate (9.19 g, 66.0 mmol) in 60 ml distilled water. After degassing carefully with argon, bis(triphenylphosphine)-palladium(II) chloride (1.40 g, 1.96 mmol) is then added, followed by hydrazinium hydroxide (0.057 ml, 1.17 mmol). The reaction mixture is heated to reflux overnight. After cooling to room temperature and aqueous work-up, the crude product is purified by column chromatography on silica gel with heptane/chlorobutane solvent mixture as eluent to provide PIn-1b as colorless oil (14.0 g).

(349) PIn-1c: To a suspension of PIn-1b (7.00 g, 17.6 mmol) in 60 ml toluene and 30 ml tetrachlorocarbon is added tetra-n-butylammoniumbromide (0.89 ml, 3.2 mmol). After warmed up to 50° C. potassium hydroxide (2.23 g, 1.96 mmol) is added very carefully to keep temperature below 75° C. After exotherm ceased, the reaction mixture is stirred at 65° C. overnight. After cooling to room temperature, neutralized carefully with 1 M aqueous HCl and aqueous work-up, the crude product is purified by column chromatography on silica gel with chlorobutane/ethyl acetate solvent mixture as eluent to provide PIn-1c as colorless oil (1.2 g).

(350) PIn-1d: A solution of PIn-1c (1.20 g, 2.91 mmol) in 18 ml dry toluene is cooled to −5° C., then tetrabutylammonium fluoride solution in THF (1 M, 3.3 ml) is added dropwise. After stirring at −5° C. for 30 min, the reaction mixture is neutralized carefully with 1 M aqueous HCl. After aqueous work-up the crude product is purified by column chromatography on silica gel with chlorobutane/ethyl acetate solvent mixture as eluent to provide PIn-1d as colorless oil (0.8 g).

(351) PIn-1: Methacrylic acid (0.40 g, 4.7 mmol) and 4-(dimethylamino)pyridine (0.038 g, 0.30 mmol) is added to a suspension of PIn-1d (0.8 g, 3.1 mmol) in 30 ml dichloromethane. The reaction mixture is treated dropwise at 0° C. with a solution of N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide (0.73 g, 4.7 mmol) in 5 ml DCM and stirred for 20 hrs at room temperature. The reaction mixture is concentrated in vacuo, and the oily residue is purified by column chromatography on silica gel with heptane/ethyl acetate as eluent and further recrystallized from methyl t-butyl ether/acetonitrile mixture to afford PIn-1 as white crystal (0.45 g, m.p. 88° C.).

(352) In analogy to Example PIn-1, the following polymerisable photoinitiators are obtained.

(353) ##STR00580##

Mixture Examples

(354) The nematic LC host mixture N1 is formulated as follows:

(355) TABLE-US-00006 CCH-35 10.00% cl.p. 79.4 CCH-501  5.00% Δn 0.0909 CCY-2-1 10.00% Δε −3.8 CCY-3-1 10.00% ε.sub.∥ 3.5 CCY-3-O2 10.00% K.sub.3/K.sub.1 0.96 CCY-5-O2 10.00% γ.sub.1 176 CPY-2-O2 12.00% V.sub.0 2.11 CY-3-O4 10.00% CY-5-O4 10.00% PCH-53 13.00%

(356) The nematic LC host mixture N2 is formulated as follows:

(357) TABLE-US-00007 BCH-32  6.50% cl.p. 74.7 CC-3-V1  8.00% Δn 0.1039 CCH-23 17.00% Δε −3.0 CCH-34  6.50% ε.sub.∥ 3.4 CCY-3-O1  3.50% K.sub.3/K.sub.1 1.07 CCY-3-O2 12.50% γ.sub.1 106 CPY-2-O2  5.50% V.sub.0 2.43 CPY-3-O2 10.00% CY-3-O2 15.50% PCH-301  4.50% PP-1-2V1  5.00% PY-3-O2  5.50%

(358) The nematic LC host mixture N3 is formulated as follows:

(359) TABLE-US-00008 CCH-35  9.00% cl.p. CCH-501  4.50% Δn CCY-2-1  9.00% Δε CCY-3-1  9.00% ε.sub.∥ CCY-3-O2  9.00% K.sub.3/K.sub.1 CCY-5-O2  9.00% γ.sub.1 CPY-2-O2 10.80% V.sub.0 CY-3-O4  9.00% CY-5-O4  9.00% PCH-53 11.70% BCH-32 10.00%

(360) Polymerisable mixtures are prepared by adding 0.3% of polymerisable non-aromatic monomer RM1, RM2 or RM3, respectively, and optionally 100 ppm of polymerisable photoinitiator PIn-1, Pn-2 or PIn-3, respectively, to each of nematic LC host mixtures N1, N2 and N3. For comparison purpose, polymerisable mixtures are prepared by adding 0.3% of polymerisable aromatic monomer RMC1 and optionally 100 ppm of polymerisable photonitiator PIn-1, PIn-2 or PIn-3, respectively, to each of nematic LC host mixtures N1, N2 and N3.

(361) ##STR00581##

(362) The compositions of the individual polymerisable mixtures are shown in Table 1a and 1 b below. Therein “P” denotes polymerisable mixtures according to the present invention and “C” denote comparison mixtures.

(363) TABLE-US-00009 TABLE 1a Polymerisable mixture composition Mix. No. C1 P1 C2 C3 LC Host N1 N1 N1 N1 Monomer RM1 RM1 RMC1 RMC1 Conc. Monomer (wt. %) 0.300 0.300 0.300 0.300 Initiator — Pln-3 — Pln-3 Conc. Initiator (ppm) — 100 — 100

(364) TABLE-US-00010 TABLE 1b Polymerisable mixture composition Mix. No. P1 P2 P3 P4 C4 P5 P6 C5 LC Host N1 N2 N2 N2 N2 N3 N3 N3 Monomer RM1 RM1 RM1 RM1 RMC1 RM2 RM3 RMC1 Conc. Monomer 0.300 0.300 0.300 0.300 0.300 0.300 0.300 0.300 (wt. %) Initiator Pln-3 Pln-3 Pln-1 Pln-3 — Pln-3 Pln-3 — Conc. Initiator 100 100 200 500 — 100 100 — (ppm)

Use Example A

(365) The individual polymerisable mixtures from Table 1a are filled into PSA test cells, the RM is polymerised under application of a voltage, and several properties like residual RM content, VHR under UV stress, tilt angle generation and tilt angle stability are measured.

(366) RM1, which is unreactive under standard PS-VA processing condition, is used together with a very low amount of a photoinitiator PIn-3 (Mixture P1) to generate tilt under exposure to standard metal-halide lamp. RMC1 is a monomer which is commonly used in PS-VA displays and is therefore used for comparison.

(367) Surprisingly the mixture P1 with non-aromatic monomer RM1 and polymerisable photoinitiator PIn-3 shows comparable or even better properties than mixtures C2 and C3 with aromatic monomer RMC1 (either with or without the polymerisable photoinitiator PIn-3). The characterizations of the most relevant parameters for PS-VA processing, including tilt generation, tilt stability, residue RM and VHR after processing, are described below respectively.

(368) During the PS-VA process a tilt angle is generated by a UV-initiated polymerization of the reactive mesogenes. The test cells used for tilt generation were PSVA-cells with a specific VA-PI. The cell gaps varied between 3.6 μm and 4.1 μm. After the cells were filled with the desired mixtures they were annealed for 10 min at 120° C. Afterwards the cells were irradiated for 1, 2, 3 or 5 minutes while being stressed with a 200 Hz 40 V.sub.pp square wave. The irradiation was done in a Hönle UVACube 2000 UV-chamber. The lamp used was a Hönle Lamp-FOZFR 100 D24 U280 E2S9. The Test Cells were set at a height in the UV Chamber where the UV light had an intensity of 100 mW/cm.sup.2. This intensity was measured before every measurement with a Hönle UVA Sensor attached to a Hönle UV meter. Afterwards the test cells were again annealed for 10 min at 120° C. The test cells were given at least 12 hours to relax before the final tilt angle was measured and calculated with an Axometrics AxoScan®. The results are shown in Table 2.

(369) TABLE-US-00011 TABLE 2 Tilt anqle Mixture UV Time/min 0 1 2 3 5 C1 Tilt/° 90 89.8 89.0 86.9 84.0 P1 90 83.7 80.8 76.4 74.2 C2 90 87.4 80.2 77.5 74.4 C3 90 84.3 77.1 75.3 74.3

(370) It can be seen that the tilt angle generated in polymerisable mixture C1, which contains the non-aromatic monomer RM1 but does not contain the polymerisable photoinitiator PIn-3, is significantly lower than in polymerisable mixture P1 which contains the non-aromatic monomer RM1 and the polymerisable photoinitiator PIn-3. It can also be seen that mixture P1 can generate a tilt angle in the same degree as mixtures C2 and 3 with the aromatic monomer RMC1.

(371) The accelerating effect of the poymerisable photoinitiator is also confirmed by the residual RM analysis. For the residual RM analysis specific test cells were used. The test cells are filled with the desired mixture. They were irradiated in an UV chamber with an UVFL lamp source which is comparable to state of the art lamp sources for the LCD mass production. The irradiation duration was 60 min at ˜2.0 mW/cm.sup.2. To measure the remaining monomer after processing the test cells were cut off and rinsed by using 500 μl of ethylmethylketone for each glass substrate of the cell. The residual amount of RM in the rinsed LC-mixture is determined using an HPLC. The results are shown in Table 3.

(372) TABLE-US-00012 TABLE 3 Residual RM content Mixture C1 P1 Residual RM/% rel. 54.1 7.9

(373) It can be seen that in polymerisable mixture C1, which contains non-aromatic monomer RM1 but does not contain polymerisable photoinititator PIn-3, after UV-exposure for 60 mins only about half (54.1%) of the originally added amount of the monomer RM1 has reacted, and the other half of RM1 still remains unreacted. In contrast thereto, in the polymerisable mixture P1 with non-aromatic monomer RM1 and polymerisable photoinitiator PIn-3, the residual amount of RM1 is reduced significantly to 7.9% of the original amount.

(374) The accelerating effect of the poymerisable photoinitiator is also confirmed by analysis of both residual reactants (RM and photoinitiator) in the mixture. For this purpose the analysis of residual amounts of RM and photoinitiator analysis was carried out in analogy to the method described above, but wherein an MH lamp was used for UV irradiation. The results are shown in Table 4.

(375) TABLE-US-00013 TABLE 4 Residual content of RM and photoinitiator Time/min 0.5 1.0 1.5 2.0 2.5 3.0 4.0 5.0 10.0 15.0 20.0 RM1/ 99.5 99.9 95.2 89.6 85.1 79.0 68.0 58.1 33.4 27.2 22.9 % rel. Pln-3/ 95.1 89.3 80.1 70.5 61.8 55.1 40.5 30.0 9.6 3.3 2.5 % rel.

(376) It can be seen that, with the complete consumption of photoinitiator PIn3, the concentration of monomer P remains nearly constant, which strongly indicates the the polymerization reaction of the remaining monomer does not proceed further.

(377) A high VHR value is usually desired to avoid occurrence of imaging sticking in LC display. The VHR value is measured as follows: desired LC-mixtures are introduced into VA-VHR test cells which comprise an unrubbed VA-polyimide alignment layer. The LC-layer thickness d is approx. 6 μm, 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 μs pulse (measuring instrument: Autronic-Melchers VHRM-105). The results are shown in Table 5.

(378) TABLE-US-00014 TABLE 5 VHR values VHR (%) Mixture initial post radiation C1 99.4 99.1 P1 99.6 99.2 C2 99.4 98.6 C3 99.5 99.2

(379) It can be seen that surprisingly the polymerisable mixture P1, which contains the non-aromatic monomer RM1 and the polymerisable photoinitiator PIn-3, after UV-processing shows even slightly higher VHR than mixture C2 with the aromatic RMC1 and the polymerisable photoinitiator.

(380) Tilt stability is also a very important parameter because any change in tilt after processing leads to an immediate change of transmission in display. The test cells filled with the desired mixtures are processed according to the tilt generation process. Afterwards a high voltage of 60V.sub.pp square wave is applied to the test cells to stress the test cells for more than 48 hours. Directly after the stress period the tilt angle is measured and compared to the tilt angle before stress. The change in tilt angle is recorded as a Δtilt. Usually the lower the Δtilt, the better is the tilt stability. The results are shown in Table 6.

(381) TABLE-US-00015 TABLE 6 Tilt Stability Δ Tilt/° Mixture 0 h 3 h 24 h C1 3.1 1.1 1.6 P1 0.4 0.4 0.2 C2 0.2 0.4 0.4 C3 0.5 0.3 0.3

(382) It can be seen that surprisingly the polymerisable mixture P1, which contains the non-aromatic monomer RM1 and the polymerisable photoinitiator PIn-3, after voltage stress shows even better tilt stability than mixture C2 with the aromatic RMC1 and the polymerisable photoinitiator.

Use Example B

(383) The individual polymerisable mixtures from Table 1 b are filled into PSA test cells. the RM is polymerised under application of a voltage, and several properties like residual RM content, VHR under UV stress, tilt angle generation and tilt angle stability are measured as described in Use Example A. The results are shown in Tables 7-10 below.

(384) TABLE-US-00016 TABLE 7 Tilt angle, tilt stability and VHR after back light test (BLT) with shortened second UV step in mixture P1 Mixture UV2 Time/min 0 15 30 60 90 120 P1 Tilt angle/° 81.9 81.8 83.0 81.7 82.2 81.4 P1 ΔTilt/° 1.5 0.4 0.2 0.2 0.3 0.3 P1 VHR after BLT/ 98.7 — 98.3 98.5 98.3 97.4 %

(385) In current commercial PS-VA display manufacturing process, the duration of the second UV processing step is usually applied for 90 to 120 min. It can be seen that in mixture P1 with shortened second UV step, the generated tilt angle is relatively stable. By applying second UV step even only for 30 min, the Δtilt can be kept clearly below 1. In addition, the VHR value after 8 days back light stress remains at high level. These results strongly indicate that the new system consisting of a non-aromatic monomer with a polymerisable photoinitiator can be applied to shorten the overall UV processing time during LC display panel production.

(386) TABLE-US-00017 TABLE 8 Tilt angle in mixture P2, P3 and P4 Mixture UV1 Time/min 1 2 3 4 8 P2 Tilt angle*/° — 0.7 — — — P3 0.5 4.1 6.0 8.1 11.2 P4 1.0 4.1 6.6 8.1 9.3 C4 1.7 5.4 6.6 8.8 10.0 *given here relative to the direction perpendicular to the substrate

(387) TABLE-US-00018 TABLE 9 Tilt stability in mixture P2 and P3 Mixture P3 ΔTilt/° 0.2 P4 0.3 C4 0.1

(388) In mixture P2 containing host N2 and 100 ppm polymerisable photoinitiator PIn-3, the tilt generation was found to be significantly reduced. However, by increasing the polymerisable photoinitiator concentration and slightly modifying the structure from PIn-3 to PIn-2, the tilt generation in mixture P3 and P4 recovered to comparable levels as in the reference mixture C4, without negative influence on the tilt stability. The Δtilt in all three mixtures are kept clearly below 1°. These results showed that with this new system it is possible to tune the speed of tilt angle generation by tuning the polymerisable photoinitiator, without necessity to change the monomer.

(389) TABLE-US-00019 TABLE 10 Tilt angle with RM2 and RM3 Mixture P1 Tilt angle/° 87.8 P4 85.5 P5 87.8 C5 81.5

(390) In mixture P3 containing host N3 and 100 ppm polymerisable photoinitiator PIn-3, slower tilt generation was observed for RM1 and RM3. However, by using RM2 tilt generation can be enhanced to an acceptable level.

Further Mixture Examples

Example P7

(391) The nematic LC host mixture N4 is formulated as follows:

(392) TABLE-US-00020 CC-3-V1 9.00% cl.p. 74.7 CCH-23 18.00% Δn 0.0982 CCH-34 3.00% Δε −3.4 CCH-35 7.00% ε.sub.|| 3.5 CCP-3-1 5.50% K.sub.1 14.9 CCY-3-O2 11.50% K.sub.3 15.9 CPY-2-O2 8.00% γ.sub.1 108 CPY-3-O2 11.00% V.sub.0 2.28 CY-3-O2 15.50% PY-3-O2 11.50%

(393) Polymerisable mixture P7 is formulated by adding 0.3% of RM1 and 200 ppm of polymerisable photoinitiator PIn-3 to host mixture N4.

Example P8

(394) The nematic LC host mixture N5 is formulated as follows:

(395) TABLE-US-00021 CC-3-V1 9.00% cl.p. 75.4 CCH-23 14.00% Δn 0.1055 CCH-34 6.00% Δε −2.8 CCH-35 6.00% ε.sub.|| 3.3 CCP-3-1 7.00% K.sub.1 16.2 CCY-3-O1 5.00% K.sub.3 17.3 CCY-3-O2 10.00% γ.sub.1 102 CPY-3-O2 12.00% V.sub.0 2.67 CY-3-O2 9.00% PP-1-2V1 8.00% PY-3-O2 12.00% PY-4-O2 1.00%

(396) Polymerisable mixture P8 is formulated by adding 0.3% of RM1 and 200 ppm of polymerisable photoinitiator PIn-1 to host mixture N5.

Example P9

(397) The nematic LC host mixture N6 is formulated as follows:

(398) TABLE-US-00022 CC-3-V1 8.00% cl.p. 74.6 CCH-23 15.00% Δn 0.0899 CCH-34 5.00% Δε −3.3 CCH-35 6.00% ε.sub.|| 3.5 CCP-3-1 3.00% K.sub.1 13.9 CCY-3-O1 8.00% K.sub.3 14.6 CCY-3-O2 10.00% γ.sub.1 114 CCY-3-O3 6.00% V.sub.0 2.22 CCY-4-O2 6.00% CY-3-O2 12.00% CY-3-O4 3.75% PCH-301 3.00% PY-3-O2 2.75% PY-4-O2 6.50% PYP-2-3 5.00%

(399) Polymerisable mixture P9 is formulated by adding 0.3% of RM1 and 100 ppm of polymerisable photoinitiator PIn-3 to host mixture N6.

Example P10

(400) The nematic LC host mixture N7 is formulated as follows:

(401) TABLE-US-00023 BCH-32 6.00% cl.p. 74.2 CCH-13 8.50% Δn 0.1107 CCH-34 8.00% Δε −3.3 CCH-35 6.00% ε.sub.|| 3.5 CCOC-3-3 0.25% K.sub.1 14.4 CCY-3-O1 4.50% K.sub.3 15.4 CCY-3-O2 13.50% γ.sub.1 125 CPY-2-O2 6.50% V.sub.0 2.28 CPY-3-O2 13.50% CY-3-O2 15.50% CY-3-O4 4.50% PCH-301 2.25% PP-1-3 11.00%

(402) Polymerisable mixture P10 is formulated by adding 0.3% of RM2 and 200 ppm of polymerisable photoinitiator PIn-1 to host mixture N7.

Example P11

(403) The nematic LC host mixture N8 is formulated as follows:

(404) TABLE-US-00024 CC-3-V1 8.00% cl.p. 75.5 CCH-23 18.00% Δn 0.0978 CCH-34 4.00% Δε −3.5 CCH-35 7.00% ε.sub.|| 3.5 CCP-3-1 5.00% K.sub.1 14.9 CCY-3-O2 12.50% K.sub.3 15.8 CPY-2-O2 8.00% γ.sub.1 111 CPY-3-O2 11.00% V.sub.0 2.26 CY-3-O2 15.50% PY-3-O2 11.00%

(405) Polymerisable mixture P11 is formulated by adding 0.3% of RM1 and 200 ppm of polymerisable photoinitiator PIn-3 to host mixture N8.

Example P12

(406) The nematic LC host mixture N9 is formulated as follows:

(407) TABLE-US-00025 CC-3-V1 8.00% cl.p. 75.3 CCH-23 16.00% Δn 0.0904 CCH-34 6.00% Δε −3.3 CCH-35 6.00% ε.sub.|| 3.5 CCP-3-1 3.50% K.sub.1 14.4 CCY-3-O1 7.00% K.sub.3 15.2 CCY-3-O2 9.00% γ.sub.1 112 CCY-3-O3 6.00% V.sub.0 2.24 CPY-3-O2 7.00% CY-3-O2 15.00% CY-3-O4 7.00% PY-3-O2 4.00% PYP-2-3 5.00%

(408) Polymerisable mixture P12 is formulated by adding 0.3% of RM1 to and 100 ppm of polymerisable photoinitiator PIn-3 host mixture N9.

Example P13

(409) The nematic LC host mixture N10 is formulated as follows:

(410) TABLE-US-00026 BCH-32 6.00% cl.p. 74.8 CC-3-V1 6.00% Δn 0.1066 CCH-34 9.00% Δε −3.3 CCH-35 7.00% ε.sub.| 3.6 CCP-3-1 8.00% K.sub.1 14.2 CCP-3-3 3.00% K.sub.3 16.5 CCY-3-1 2.00% γ.sub.1 118 CCY-3-O2 10.50% V.sub.0 2.35 CCY-4-O2 5.00% CPY-3-O2 3.50% CY-3-O2 14.00% PCH-301 5.50% PY-1-O4 6.50% PY-3-O2 14.00%

(411) Polymerisable mixture P13 is formulated by adding 0.3% of RM1 and 200 ppm of polymerisable photoinitiator PIn-1 to host mixture N10.

Example P14

(412) The nematic LC host mixture N11 is formulated as follows:

(413) TABLE-US-00027 CC-3-V 15.00% cl.p. 74.4 CC-3-V1 9.00% Δn 0.1086 CCH-23 8.00% Δε −3.2 CCH-34 7.50% ε.sub.|| 3.5 CCY-3-O2 10.00% K.sub.1 14.3 CCY-5-O2 8.00% K.sub.3 15.7 CPY-2-O2 3.00% γ.sub.1 102 CPY-3-O2 8.50% V.sub.0 2.33 CY-3-O2 7.00% PY-3-O2 16.00% PYP-2-3 8.00%

(414) Polymerisable mixture P14 is formulated by adding 0.3% of RM3 and 100 ppm of polymerisable photoinitiator PIn-3 to host mixture N11.

Example P15

(415) The nematic LC host mixture N12 is formulated as follows:

(416) TABLE-US-00028 CCH-23 15.00% cl.p. 84.8 CCH-34 10.00% Δn 0.1025 CCP-3-1 7.00% Δε −3 CCP-3-3 6.00% ε.sub.| 3.4 CCY-2-1 4.00% K.sub.1 14.6 CY-3-O2 15.00% K.sub.3 15.7 CY-3-O4 8.50% γ.sub.1 134 CCY-3-O2 9.00% V.sub.0 2.4 CPY-2-O2 8.00% CPY-3-O2 8.00% PYP-2-3 5.00% BCH-32 4.50%

(417) Polymerisable mixture P15 is formulated by adding 0.3% of RM3 and 100 ppm of polymerisable photoinitiator PIn-3 to host mixture N12.

Example P16

(418) The nematic LC host mixture N13 is formulated as follows:

(419) TABLE-US-00029 B-2O-O5 4.00% cl.p. 74.2 BCH-32 8.00% Δn 0.1091 CC-3-V1 9.00% Δε −3.1 CCH-301 2.00% ε.sub.|| 3.6 CCH-34 8.00% K.sub.1 14.5 CCH-35 7.00% K.sub.3 16.5 CCP-3-1 8.00% γ.sub.1 108 CCP-V2-1 5.00% V.sub.0 2.41 CCY-3-O2 10.50% CLY-3-O2 1.00% CPY-3-O2 2.50% CY-3-O2 11.50% PCH-301 5.50% PY-3-O2 18.00%

(420) Polymerisable mixture P16 is formulated by adding 0.3% of RM2 and 200 ppm of polymerisable photoinitiator PIn-1 to host mixture N13.