Liquid crystal medium

Abstract

To provide a liquid crystal medium.SOLUTION: The present invention relates to a liquid crystal (LC: liquid-crystalline) medium having positive dielectric constant anisotropy and a liquid crystal display including these media (LCD: liquid-crystal display), particularly a display addressed by active matrix, especially TN, PS-TN, STN, TN-TFT, OCB, IPS, PS-IPS, FFS, HB-FFS, XB-FFS, PS-FFS, SA-HB-FFS, SA-XB-FFS, polymer stabilized SA-HB-FFS, polymer stabilized SA-XB-FFS, positive VA or positive PS-VA type LC display.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to liquid-crystalline (LC) media having positive dielectric anisotropy, liquid-crystal displays (LCDs) comprising these media, and in particular displays addressed by an active matrix, in particular TN, PS-TN, STN, TN-TFT, OCB, IPS, PS-IPS, FFS, HB-FFS, PS-HB-FFS, SA-HB-FFS, polymer-stabilized SA-HB-FFS, positive VA or positive PS-VA type liquid-crystal displays.

Background Art

[0002] Liquid-crystal displays (LCDs) are used in many fields for displaying information. LCDs are used in both direct-view displays and projection displays. The electro-optical modes used are, for example, the twisted nematic (TN), super twisted nematic (STN), optically compensated bend (OCB) and electrically controlled birefringence (ECB) modes, together with their various improved versions. All of these modes utilize an electric field generated substantially perpendicular to the substrates and the liquid-crystal layer.

[0003] In addition to these modes, there are also electro-optical modes that utilize an electric field substantially parallel to the substrate or the liquid crystal layer. For example, International Publication No. WO91 / 10936 (Patent Document 1) discloses a liquid crystal display in which an electric signal is generated such that the electric field has a significant component parallel to the liquid crystal layer, and thereafter it has come to be known as an in-plane switching (IPS) display. The operating principle of such a display is described, for example, in R.A. Soref, Journal of Applied Physics, Vol. 45, No. 12, pp. 5466 - 5468 (1974) (Non-Patent Document 1).

[0004] The IPS display includes an LC layer between two substrates arranged in a plane, and two electrodes are arranged on only one of the two substrates, preferably having an interdigitated comb-like structure. When a voltage is applied to the electrodes, an electric field having a significant component parallel to the LC layer is generated between the electrodes. As a result, reorientation of the LC molecules occurs within the layer plane.

[0005] For example, European Patent No. 0 588 568 (Patent Document 2) discloses various possibilities for the design of the electrodes and for addressing the IPS display. Similarly, German Patent Application Publication No. 198 24 137 (Patent Document 3) describes various embodiments of such an IPS display.

[0006] A liquid crystal material for this type of IPS display is described, for example, in German Patent Application Publication No. 195 28 104 (Patent Document 4).

[0007] Furthermore, so-called "fringe-field switching" (FFS) displays have been reported (see, in particular, S.H. Jung et al., Jpn. J. Appl. Phys., Vol. 43, No. 3, 2004, p. 1028 (Non-Patent Document 2)), and the display includes two electrodes on the same substrate, one of which is structured in a comb shape and the other is unstructured. This generates a strong so-called "fringe electric field", that is, a strong electric field near the ends of the electrodes and an electric field having both a strong vertical component and a strong horizontal component throughout the cell. The FFS display has a small viewing angle dependence of contrast. The FFS display usually includes an LC medium having a positive dielectric anisotropy and an alignment layer, usually polyimide, that gives a planar alignment to the molecules of the LC medium.

[0008] Liquid crystal displays in the IPS and FFS electro-optical modes are particularly suitable for use in modern desktop monitors, television sets, and multimedia applications, but are also suitable for use in mobile phones, tablet PCs, etc. The liquid crystal medium according to the present invention is preferably used in this type of display. Generally, in FFS displays, a dielectrically positive liquid crystal medium having a rather low value of dielectric anisotropy is used, but in some cases, a liquid crystal medium having a dielectric anisotropy of only about 3 or less is also used in IPS displays.

[0009] Further improvements have been achieved by the HB-FFS mode. The HB-FFS mode is characterized by higher transmittance and the ability to operate the panel with less energy consumption, in contrast to conventional FFS technology.

[0010] Liquid crystal compositions suitable for LCDs, especially FFS and IPS displays, are known, for example, from JP-A-07-181439 (Patent Document 5), EP 0 667 555 (Patent Document 6), EP 0 673 986 (Patent Document 7), DE 195 09 410 (Patent Document 8), DE 195 28 106 (Patent Document 9), DE 195 28 107 (Patent Document 10), WO 96 / 23851 (Patent Document 11), and WO 96 / 28521 (Patent Document 12). However, these compositions have certain drawbacks. Among other deficiencies, most of them result in undesirably long addressing times, have inappropriate resistivity values, and / or require unduly high operating voltages. Improvements are needed in both operating characteristics and storage stability in this specification.

[0011] FFS and IPS displays can operate as active-matrix displays (AMD) or passive-matrix displays (PMD). In the case of active-matrix displays, individual pixels are usually addressed by integrated non-linear active elements such as thin-film transistors (TFTs), while in the case of passive-matrix displays, individual pixels are usually addressed by a multiplexing method as known from the prior art.

[0012] The display according to the invention is preferably based on an active matrix, preferably a TFT matrix. However, the liquid crystals according to the invention can also be advantageously used in displays having other known addressing means.

[0013] Both IPS technology and FFS technology have certain advantages compared to other LCD technologies such as vertical alignment (VA) technology, such as a wide viewing angle dependence of contrast.

[0014] The provision and use of further LC media in displays having high transmittance, good black state and high contrast ratio are central issues in recent FFS and IPS applications. Additionally, in the latest applications, good low temperature stability and fast addressing time are also required. By improving the transmittance in the bright state and good dark state, the contrast can be improved. One solution to improve the dark state is to develop a liquid crystal mixture with a high average elastic constant (K av ) to lower the scattering parameter of the liquid crystal mixture, but this usually has the drawback of a short response time.

[0015] In displays such as the HB-FFS mode, it has been observed that high brightness can be achieved by using a liquid crystal medium having positive dielectric anisotropy and an increased dielectric constant ε ⊥ also increased perpendicular to the longitudinal axis of the liquid crystal molecules. This can be achieved by adding a limited amount of a liquid crystal compound having negative dielectric anisotropy with high ε ⊥ characteristics to the liquid crystal medium, and the positive dielectric anisotropy of the whole medium is maintained. However, the addition of compounds having high ε ⊥ has several drawbacks. For example, the value of the rotational viscosity γ 1 becomes high, and as a result, the ratio γ 1 of the value of the rotational viscosity γ 22 to the elastic constant K 1 of the twist deformation becomes high, and the response time becomes long. Since K 22 is almost proportional to the elastic constant K 22 of the spray deformation (the value of K 11 is usually about half of the value of K 22 ), it can be easily determined by measuring γ 11 and K 1 and K 11 .

[0016] Another drawback is that the reliability (VHR) of the HB-FFS mixture may be inferior to that of the conventional FFS mixture.

[0017] It is also important to maintain excellent low-temperature stability (LTS) of the medium. Especially in a car navigation system, good LTS is required even at -40°C. Due to this requirement, it is difficult to further improve the optical performance.

Prior Art Documents

Patent Documents

[0018]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

Patent Document 8

Patent Document 9

Patent Document 10

Patent Document 11

Patent Document 12

Non-Patent Documents

[0019]

Non-Patent Document 1

[0020] The present invention is particularly for FFS and IPS displays, but also for TN, positive VA or STN displays, and in particular for active - matrix displays such as those addressed by TFTs. It has an object to provide a liquid - crystal medium, which does not show the above - mentioned drawbacks, or shows them only to a lower degree, and in particular, preferably enables a display with improved contrast without degrading other display parameters.

[0021] To solve this problem, the present invention provides a liquid - crystal medium according to claim 1.

[0022] Advantageous embodiments of the present invention are the subject of the dependent claims or can also be read from the specification. [[Means for Solving the Problems]]

[0023] The present invention preferably relates to a liquid - crystal medium containing a) one or more compounds of formula I and b) one or more compounds selected from the group of compounds of formula II and III, which has positive dielectric anisotropy.

[0024] [[Chemical Formula]] In the formula, R 11 and R 12is, same or different, linear alkyl or alkoxy having H, 1 to 15 C atoms or linear alkenyl or alkenyloxy having 2 to 15 C atoms, or branched alkyl, alkoxy, alkenyl or alkenyloxy each having 3 to 15 C atoms (in which one or more CH2 groups are, independently of one another, so that O atoms are not directly linked to one another,

Chemical formula

[0025]

Chemical formula

Chemical formula

[0026] By combining the compound of formula I with the compound of formula II and / or III, a low rotational viscosity and a γ 1 / K 22 and γ 1 / K 11 ratio can be achieved. As a result, in particular in HB-FFS, FFS and IPS mode liquid crystal displays, high brightness and transmittance, and fast response times can be achieved. Furthermore, while maintaining other relevant physical properties, a higher average elastic constant (K av ) can be achieved, so that the scattering parameter is reduced, the dark state of the display is improved and the contrast is increased.

[0027] In particular, the medium according to the invention has a very high low temperature stability (LTS). Since it is sufficiently stable even at a low temperature of -40 ° C, it is particularly suitable for mobile applications such as automotive applications.

[0028] The liquid crystal medium according to the invention is suitable for mobile applications such as mobile phones and PDAs and TFT applications. Furthermore, the liquid crystal medium according to the invention is particularly suitable for FFS, HB-FFS and IPS displays based on a dielectrically positive liquid crystal.

[0029] The liquid crystal medium according to the invention is likewise suitable for use in FFS, HB-FFS, and IPS mode liquid crystal displays for large television applications, based on dielectrically positive liquid crystals and their polymer-stabilized modifications.

[0030] The present invention further relates to using the above and below-described liquid crystal media for electro-optical purposes, in particular for liquid crystal displays, shutter glasses, LC windows, 3D applications, preferably TN, PS-TN, STN, TN-TFT, OCB, IPS, PS-IPS, FFS, HB-FFS, PS-HB-FFS, SA-HB-FFS, polymer-stabilized SA-HB-FFS, positive VA, and positive PS-VA displays, very preferably FFS, HB-FFS, IPS, PS-HB-FFS, and PS-IPS displays.

[0031] The present invention further relates to an electro-optical liquid crystal display comprising the above and below-described liquid crystal media, in particular TN, PS-TN, STN, TN-TFT, OCB, IPS, PS-IPS, FFS, HB-FFS, PS-HB-FFS, SA-HB-FFS, polymer-stabilized SA-HB-FFS, positive VA or positive PS-VA displays, preferably FFS, HB-FFS, IPS, PS-HB-FFS or PS-IPS displays.

[0032] The present invention further relates to a compound of formula I.

[0033]

Chemical formula

Chemical formula

[0034] According to another aspect of the present invention, a compound of formula (3) defined in Scheme 1 below is provided.

[0035] The compound of formula I can be synthesized in the same manner as the synthesis of structurally related chlorofluoro derivatives shown in European Patent Application Publication No. 1897928.

[0036] A preferred synthetic route for the compound of formula I is shown in Scheme 1.

Chemical formula

[0037] In this specification, an alkyl group and / or an alkoxy group means a linear or branched or cyclic alkyl. It is preferably linear and has 2, 3, 4, 5, 6 or 7 C atoms, and accordingly preferably represents ethyl, propyl, butyl, pentyl, hexyl, heptyl, ethoxy, propoxy, butoxy, pentoxy, hexyloxy or heptyloxy, and further methyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, methoxy, octyloxy, nonyloxy, decyloxy, undecyloxy, dodecyloxy, tridecyloxy or tetradecyloxy.

[0038] In this specification, the branched alkyl is preferably isopropyl, s-butyl, isobutyl, isopentyl, 2-methylbutyl, 2-methylhexyl or 2-ethylhexyl.

[0039] In this specification, the cyclic alkyl is a straight-chain or branched alkyl or alkenyl having up to 12 C atoms, preferably an alkyl having 1 to 7 C atoms, where the CH2 group is replaced by a carbocyclic ring having 3 to 5 C atoms, and is very preferably selected from the group consisting of cyclopropylalkyl, cyclobutylalkyl, cyclopentylalkyl and cyclopentenylalkyl, where the alkyl is a straight-chain alkyl having 1 to 5 C atoms.

[0040] In this specification, the oxaalkyl preferably represents linear 2-oxapropyl (= methoxymethyl), 2-(= ethoxymethyl) or 3-oxabutyl (= 2-methoxyethyl), 2-, 3- or 4-oxapentyl, 2-, 3-, 4- or 5-oxahexyl, 2-, 3-, 4-, 5- or 6-oxaheptyl, 2-, 3-, 4-, 5-, 6- or 7-oxaoctyl, 2-, 3-, 4-, 5-, 6-, 7- or 8-oxanonyl, 2-, 3-, 4-, 5-, 6-, 7-, 8- or 9-oxadecyl.

[0041] In this specification, the alkyl group in which one CH2 group is replaced by -CH=CH- may be linear or branched. It is preferably linear and has 2 to 10 C atoms. Thus, it particularly represents vinyl, prop-1- or -2-enyl, but-1-, -2- or -3-enyl, pent-1-, -2-, -3- or -4-enyl, hex-1-, -2-, -3-, -4- or -5-enyl, hept-1-, -2-, -3-, -4-, -5- or -6-enyl, oct-1-, -2-, -3-, -4-, -5-, -6- or -7-enyl, non-1-, -2-, -3-, -4-, -5-, -6-, -7- or -8-enyl, dec-1-, -2-, -3-, -4-, -5-, -6-, -7-, -8- or -9-enyl.

[0042] In this specification, an alkyl or alkenyl group that is at least monosubstituted with a halogen is preferably linear, and the halogen is preferably F or Cl. In the case of polysubstitution, the halogen is preferably F. Also included as a resulting group is a perfluoro group. In the case of monosubstitution, the fluorine or chlorine substituent may be at any desired position, but is preferably at the ω-position.

[0043] In this specification, a monofluorinated or polyfluorinated alkyl or alkoxy group having 1, 2, or 3 C atoms or a monofluorinated or polyfluorinated alkenyl group having 2 or 3 C atoms is particularly preferably F, Cl, CF3, CHF2, OCF3, OCHF2, OCFHCF3, OCFHCHF2, OCFHCHF2, OCF2CH3, OCF2CHF2, OCF2CHF2, OCF2CF2CHF2, OCF2CF2CHF2, OCFHCF2CF3, OCFHCF2CHF2, OCF2CF2CF3, OCF2CF2CClF2, OCClFCF2CF3, OCH=CF2 or CH=CF2, very particularly preferably F or OCF3, and further CF3, OCF=CF2, OCHF2 or OCH=CF2.

[0044] The compound of formula I is preferably selected from the compounds of formulas I-1 to I-4.

Chemical formula

Chemical formula

[0045] More preferably, the medium according to the present invention contains one or more compounds of formula I-1, and very preferably is selected from the compounds of formulae I-1-1 to I-1-32.

[0046]

Chemical formula

[0047]

Chemical formula

[0048]

Chemical formula

[0049]

Chemical formula

[0050] In the formula, R 11 and R 12 represent linear alkyl having 1 to 7 C atoms or linear alkenyl having 2 to 7 C atoms.

[0051] The compound of formula I-2 is preferably selected from the compounds of formulae I-2-1 to I-2-32.

[0052]

Chemical formula

[0053]

Chemical formula

[0054]

Chemical formula

[0055]

Chem.

[0056]

Chem.

[0057] The compound of formula I-3 is preferably selected from the compounds of formulas I-3-1 to I-3-32.

[0058]

Chem.

[0059]

Chem.

[0060]

Chem.

[0061]

Chem.

[0062]

Chem.

[0063] The compound of formula I-4 is preferably selected from the compounds of formulas I-4-1 to I-4-32.

[0064]

Chem.

[0065]

Chem.

[0066]

Chem.

[0067]

Chem.

[0068]

Chem.

[0069] Preferably, the medium contains one or more compounds of formula II, preferably selected from the group of compounds of formulae II-1 to II-3, and very preferably selected from the group of compounds of formulae II-1 and II-3.

[0070]

Chem.

Chem.

[0071] In formulae II-1, II-2 and II-3, L 21 and L 22 or L 23 and L 24 are preferably both F.

[0072] In another preferred embodiment of formulae II-1 and II-2, all of L 21 , L 22 , L 23 and L 24 represent F.

[0073] The compound of formula II-1 is preferably selected from the group of compounds of formulae II-1a to II-1h.

[0074]

Chemical formula

[0075]

Chemical formula

[0076] In a preferred embodiment of the present invention, the medium comprises one or more compounds selected from the group of compounds of formulae II-1a to II-1h, wherein L 21 and L 22 , and / or L 23 and L 24 are both F.

[0077] In another preferred embodiment, the medium comprises a compound selected from the group of compounds of formulae II-1a to II-1h, wherein L 21 , L 22 , L 23 and L 24 are all F.

[0078] Particularly preferred compounds of formula II-1 are

Chemical formula

[0079] Preferably, the compound of formula II-2 is selected from the group of compounds of formulae II-2a to II-2c.

[0080]

Chemical formula

[0081] Preferably, the compound of formula II-3 is selected from the group of compounds of formulae II-3a to II-3e.

[0082]

Chemical formula

[0083] Particularly preferred compounds of formula II-3 are

Chemical formula

[0084] In addition to the preferred compounds of formula II above, the medium optionally contains one or more compounds of formula II selected from the compounds of formulae IIA1 to IIA7.

[0085]

Chemical formula

[0086]

Chemical formula

[0087] Preferred compounds are compounds represented by formulas IIA1, IIA2, and IIA3, and particularly preferred are compounds represented by formulas IIA1 and IIA2.

[0088] In the compounds represented by formulas IIA1 to IIA7, R 2 is preferably alkyl having 1 to 6 C atoms, particularly preferably ethyl or n-propyl, and X 2 is preferably F or OCF3, and particularly preferably F.

[0089] In another preferred embodiment of the present invention, the medium preferably contains one or more compounds of formula III, preferably represented by formula III-2, selected from the group of formulas III-1 and III-2.

[0090]

Chemical formula

[0091] R 3 preferably represents alkyl having 1 to 7 C atoms or alkenyl having 2 to 7 C atoms.

[0092] Preferably, the compound of formula III-1 is selected from the group of compounds of formulas III-1a and III-1b.

[0093]

Chemical formula

[0094] The compound of formula III-1a is preferably selected from the group of compounds of formulas III-1a-1 to III-1a-6.

[0095]

Chemical formula

[0096] Preferably, the compound of formula III-2 is selected from the group of compounds of formulae III-2a to III-2m.

[0097]

Chemical formula

[0098]

Chemical formula

[0099]

Chemical formula

[0100] The compound of formula III-2a is preferably selected from the group of compounds of formulae III-2a-1 to III-2a-4.

[0101]

Chemical formula

[0102] The compound of formula III-2b is preferably selected from the group of compounds of formulae III-2b-1 to III-2b-2, preferably the compound of formula III-2b-2.

[0103]

Chemical formula

[0104] The compound of formula III-2c is preferably selected from the group of compounds of formulae III-2c-1 to III-2c-5.

[0105]

Chemical formula

[0106] The compounds of formula III-2d and formula III-2e are preferably selected from the group of compounds of formulae III-2d-1 and III-2e-1.

[0107]

Chemical formula

[0108] The compound of formula III-2f is preferably selected from the group of compounds of formulae III-2f-1 and III-2f-7.

[0109]

Chemical formula

[0110] The compound of formula III-2g is preferably selected from the group of compounds of formulae III-2g-1 to III-2g-7.

[0111]

Chemical formula

[0112] The compound of formula III-2h is preferably selected from the group of compounds of formulae III-2h-1 to III-2h-5.

[0113]

Chemical formula

[0114] The compound of formula III-2i is preferably selected from the group of compounds of formulae III-2i-1 to III-2i-3.

[0115]

Chemical formula

[0116] The compound of formula III-2j is preferably selected from the group of compounds of formulae III-2j-1 to III-2j-3.

[0117]

Chemical formula

[0118] The compound of formula III-2k is preferably selected from the group of compounds of formulae III-2k-1 to III-2k-6.

[0119]

Chemical formula

[0120] The compound of formula III-2l is preferably selected from the group of compounds of formulae III-2l-1 to III-2l-6.

[0121]

Chemical formula

[0122] The compound of formula III-2m is preferably selected from the compound of formula III-2m-1.

[0123] [Chemical formula]

[0124] Alternatively, in addition to the compounds of formula III-1 and / or formula III-2, the medium according to the invention optionally comprises one or more compounds of formula III-3.

[0125] [Chemical formula]

[0126] In the formula, the groups and parameters have the meanings shown in formula III above, and are preferably represented by formula III-3a.

[0127] [Chemical formula] In the formula, R 3 has the meaning shown above.

[0128] In addition to the preferred compounds of formula III above, the medium optionally comprises one or more compounds selected from the group consisting of formulas IIIA-1 to IIIA-21.

[0129] [Chemical formula]

[0130] [Chemical formula]

[0131] [Chemical formula]

[0132] [Chemical formula]

[0133] wherein R 3 and X 3 has either the meaning given by formula III or a preferred meaning given above and below. Preferred compounds are those represented by formulae IIIA1, IIIA4, IIIA6, IIIA16, IIIA19 and IIIA20.

[0134] In the compounds of formulae IIIA1 to IIIA21, R 3 preferably represents alkyl having 1 to 6 C atoms, particularly preferably ethyl or propyl, and X 3 preferably represents F or OCF3, particularly preferably F.

[0135] Preferably, the medium according to the invention comprises one or more compounds represented by formula IV.

[0136]

Chemical formula

[0137] The compound of formula IV is preferably selected from the group of compounds of formulae IV-1 to IV-4, and very preferably from the group of compounds of formula IV-3.

[0138]

Chemical formula

[0139] Wherein, alkyl and alkyl’ each independently represent an alkyl having 1 to 7 carbon atoms, preferably an alkyl having 1 to 5 carbon atoms, alkoxy represents an alkoxy having 1 to 5 carbon atoms, preferably an alkoxy having 2 to 4 carbon atoms, alkenyl represents an alkenyl group having 2 to 5 carbon atoms, preferably 2 to 4 carbon atoms, particularly preferably 2 carbon atoms, alkenyl’ represents an alkenyl group having 2 to 5 carbon atoms, preferably 2 to 4 carbon atoms, particularly preferably 2 to 3 carbon atoms.

[0140] Preferably, the medium preferably contains one or more compounds of formula IV-1 selected from the group of compounds of formulae IV-1-1 to IV-1-6.

[0141]

Chemical formula

[0142] Preferably, the medium of the present invention contains one or more compounds of formula IV-2-1 and / or IV-2-2.

[0143]

Chemical formula

[0144] Preferably, the medium of the present invention contains a compound of formula IV-3, very preferably a compound of formulae IV-3-1 to IV-3-6, particularly IV-3-2 and / or IV-3-3.

[0145]

Chem.

[0146] Preferably, the medium according to the invention comprises a compound selected from the compounds of formula IV-4, in particular of formulae IV-4-1 and IV-4-2.

[0147]

Chem.

[0148] Preferably, the liquid crystal medium of the invention comprises one or more compounds of formula IVa and / or IVb, very preferably of formula IVb.

[0149]

Chem.

[0150] wherein R 41 and R 42 each independently represent a straight-chain alkyl, alkoxy, alkenyl, alkoxyalkyl or alkoxy group having up to 12 carbon atoms, and

Chem.

[0151] Preferred compounds of formula IVa are selected from the compounds of formulae IVa-1 to IVa-4.

[0152]

Chem.

[0153] wherein alkyl and alkyl * each independently represents a linear alkyl group having 1 to 6 carbon atoms.

[0154] The medium according to the invention preferably comprises at least one compound of formula IVa-2.

[0155] Preferred compounds of formula IVb are selected from the compounds of formulae IVb-1 to IVb-3.

[0156]

Chemical formula

[0157] wherein alkyl and alkyl * each independently represents a linear alkyl group having 1 to 6 carbon atoms, and alkenyl and alkenyl * each independently represents a linear alkenyl group having 2 to 6 carbon atoms.

[0158] Among the compounds of formulae IVb-1 to IVb-3, the compound of formula IVb-2 is particularly preferred.

[0159] Particularly preferred compounds of formula IVb are selected from the following compounds.

[0160]

Chemical formula

[0161] The medium according to the invention particularly preferably comprises compound IVb-2-3.

[0162] In a particularly preferred embodiment, the medium according to the invention comprises one or more compounds of formula V.

[0163]

Chemical formula

[0164] In the formula, R 51 , R 52 represents alkyl having 1 to 7 carbon atoms, alkoxy having 1 to 7 carbon atoms, or alkoxyalkyl, alkenyl or alkenyloxy having 2 to 7 carbon atoms, [Chemical formula] represents Z 51 , Z 52 each independently represents -CH2-CH2-, -CH2-O-, -CH=CH-, -C≡C-, -COO- or a single bond, and n is 1 or 2, provided that the compounds of formula I and CL are excluded.

[0165] The compound of formula V is preferably selected from the compounds of formula V-1, V-2, V-3 and V-4.

[0166] [Chemical formula]

[0167] In the formula, the groups appearing have the meanings given above for formula V.

[0168] The compound of formula V-1 is preferably selected from the compounds of formula V-1-1 to V-1-8; The compound of formula V-2 is preferably selected from the compounds of formula V-2-1 to V-2-4; and The compound of formula V-3 is preferably selected from the compounds of formula V-3-1 to V-3-4.

[0169] [Chemical formula]

[0170] [Chemical formula]

[0171] In the formula, R 51 and R 52 have the meanings shown above in formula V. R 51 and R 52 preferably each independently represent a linear alkyl having 1 to 7 C atoms or an alkenyl having 2 to 7 C atoms.

[0172] Very preferred compounds of formula V-2-1 are selected from the compounds of formulae V-2-1a to V-2-1g.

[0173]

Chemical formula

[0174] Very preferred compounds of formula V-2-2 are selected from the compounds of formulae V-2-2a to V-2-2i.

[0175]

Chemical formula

[0176] Preferably, the medium according to the present invention contains one or more compounds of formula CL.

[0177]

Chemical formula

[0178] In the formula R L represents H, a linear or branched alkyl or alkoxy group having 1 to 15 C atoms or a linear or branched alkenyl group having 2 to 15 C atoms, provided that in these groups, one or more CH2 groups are arranged such that O atoms are not directly connected to each other,

Chemical formula

[0179] The compound of formula CL is preferably selected from the group of compounds of formula CL-1, CL-2 and CL-3.

[0180]

Chemical formula

[0181] wherein, R L1 and R L2 are the same or different and have the meanings given above for formula I, preferably represent alkyl or alkenyl having 1 to 7 or 2 to 7 C atoms respectively, and in the group, the CH2 group may be replaced by cyclopropane-1,2-diyl, or R L2 represents alkoxy having 1 to 5 C atoms.

[0182] The highly preferred compound of formula CL is selected from the compounds of formula CL-3-1 to CL-3-12.

[0183]

Chemical formula

[0184]

Chemical formula

[0185] In a particularly preferred embodiment, the medium according to the invention comprises the compound CL-3-1 or CLP-3-3.

[0186] In a preferred embodiment of the invention, the medium additionally comprises one or more compounds of formulae VI-1 to VI-9.

[0187]

Chemical formula

[0188]

Chemical formula

[0189] wherein R 6 each independently has one of the meanings indicated for R 1 in claim 1, w is an integer from 1 to 6, each independently of one another.

[0190] In a preferred embodiment of the invention, the medium further comprises one or more compounds of formula VII.

[0191]

Chemical formula

[0192] wherein R 71 and R 72 represent H, F, a linear alkyl or alkoxy having 1 to 15 C atoms, a linear alkenyl or alkenyloxy having 2 to 15 C atoms or a branched alkyl, alkoxy, alkenyl or alkenyloxy having 3 to 15 C atoms, provided that in these groups one or more CH2 groups are arranged such that O atoms are not directly linked to one another,

Chemical formula

[0193] The compound of formula VII is preferably selected from formula VII-1 and VII-2.

[0194]

Chemical formula

[0195] In the formula, the groups appearing have the meanings shown in formula VII.

[0196] The compound of formula VII-1 is preferably selected from formula VII-1-1 to VII-1-21, very preferably from formula VII-1-4.

[0197]

Chemical formula

[0198]

Chemical formula

[0199]

Chemical formula

[0200] In the formula, R 7 represents a linear alkyl or alkoxy group having 1 to 6 carbon atoms, (O) represents -O- or a single bond, m is 0, 1, 2, 3, 4, 5 or 6, and n is 0, 1, 2, 3 or 4. R 7 preferably represents methyl, ethyl, propyl, butyl, pentyl, hexyl, methoxy, ethoxy, propoxy, butoxy, pentyloxy.

[0201] In the compound of formula VII-1-4, (O) preferably represents -O-.

[0202] The compound of formula VII-2 is preferably selected from formulas VII2-1 to VII2-15, and very preferably from formula VII-2-1.

[0203]

Chemical formula

[0204]

Chemical formula

[0205]

Chemical formula

[0206] In the formula, R 7 represents a linear alkyl or alkoxy group having 1 to 6 carbon atoms, (O) represents -O- or a single bond, m is 0, 1, 2, 3, 4, 5 or 6, and n is 0, 1, 2, 3 or 4. R 7 preferably represents methyl, ethyl, propyl, butyl, pentyl, hexyl, methoxy, ethoxy, propoxy, butoxy, pentyloxy.

[0207] Preferably, the medium according to the present invention contains one or more compounds of formula VIII.

[0208] [Chemical formula]

[0209] In the formula, R 81 and R 82 represent the same or different H, halogen, CN, SCN, linear alkyl or alkoxy having 1 to 15 C atoms, linear alkenyl or alkenyloxy having 2 to 15 C atoms, or branched alkyl, alkoxy, alkenyl or alkenyloxy having 3 to 15 C atoms, provided that one or more CH2 groups in these groups are such that O atoms are not directly linked to each other. [Chemical formula] -C≡C-, -CF2O-, -OCF2-, -CH=CH-, -O-, -CO-O- or -O-CO-, and each may be independently replaced by each other, and one or more H atoms in the group may be replaced by halogen. A 0 A 81 and A 82 each independently represent phenylene-1,4-diyl (one or two CH groups in the group may be replaced by N, and one or more H atoms may be replaced by halogen, CN, CH3, CHF2, CH2F, CF3, OCH3, OCHF2 or OCF3), cyclohexane-1,4-diyl (one or two non-adjacent CH2 groups in the group may be independently replaced by O and / or S, and one or more H atoms may be replaced by F), cyclohexene-1,4-diyl, bicyclo[1.1.1]pentane-1,3-diyl, bicyclo[2.2.2]octane-1,4-diyl, spiro[3.3]heptane-2,6-diyl, tetrahydropyran-2,5-diyl or 1,3-dioxane-2,5-diyl; Z 81 and Z 82each independently represents -CF2O-, -OCF2-, -CH2O-, -OCH2-, -CO-O-, -O-CO-, -C2H4-, -C2F4-, -CF2CH2-, -CH2CF2-, -CFHCFH-, -CFHCH2-, -CH2CFH-, -CF2CFH-, -CFHCF2-, -CH=CH-, -CF=CH-, -CH=CF-, -CF=CF-, -C≡C- or a single bond; n represents 0, 1, 2 or 3, preferably 0, 1 or 2, very preferably 0 or 1, particularly preferably 0; and m represents 0, 1, 2 or 3, preferably 0, 1 or 2, very preferably 1 or 2, particularly 1, provided that the compound of formula I is excluded from the compound of formula VIII.

[0210] A in formula I 81 and A 81 preferably represent phenylene-1,4-diyl (and this group may be mono- or polysubstituted with F), further cyclohexane-1,4-diyl, cyclohexenylene-1,4-diyl, tetrahydropyran-2,5-diyl or 1,3-dioxane-2,5-diyl, very preferably phenylene-1,4-diyl (and this group may be mono- or polysubstituted with F) or cyclohexane-1,4-diyl.

[0211] Z in formula VIII 81 and Z 81 preferably represent -CF2O-, -OCF2- or a single bond, very preferably a single bond.

[0212] A in formula VIII 81 and A 81 are particularly preferably

Chemical formula

[0213] R 81 and R 82Each independently represents H, F, or an alkyl, alkoxy, alkenyl, or alkynyl having 1 to 8, preferably 1 to 5 C atoms, and each of said groups may be replaced by a halogen, particularly F. Compounds of formula VIII are more preferred.

[0214] R 81 and R 82 preferably represent H, a fluorinated alkyl or alkoxy having 1 to 7 C atoms, a fluorinated alkenyl or alkynyl having 2 to 7 C atoms, or a fluorinated cycloalkyl having 3 to 12 C atoms.

[0215] Preferably, at least one of R 81 and R 82 is not H, and particularly preferably, neither R 81 nor R 82 is H. R 81 is very particularly preferably alkyl. R 82 is more preferably H, alkyl, or F. Very particularly preferably, R 81 is alkyl, and R 82 is H or alkyl. R 81 R 82 each independently very particularly preferably represents an unbranched alkyl having 1 to 5 C atoms. When R 81 and R 82 represent a substituted alkyl, alkoxy, alkenyl, or alkynyl, the total number of C atoms in the two groups R 81 and R 82 is preferably less than 10.

[0216] Preferred compounds of formula VIII are selected from the following sub-formulas, more preferably compounds of formula VIII-3.

[0217]

Chemical formula

[0218] In the formula, R 81and R 82 has the meaning indicated above, L represents F, and r, s, and t are independently 0, 1, 2, 3, or 4. r is preferably 1 or 2, very preferably 2, and s and t are independently preferably 0 or 1, very preferably 0. R 81 and R 82 in particular independently represent n-alkyl having 1 to 5 C atoms.

[0219] In a first very preferred embodiment, the compounds of formulas VIII-1 to VIII-6 are selected from the compounds of formulas VIII-1a to VIII-6a, in particular the compound of formula VIII-3a.

[0220]

Chemical formula

[0221] wherein R 81 , R 82 , L, r, and s have the meanings defined above.

[0222] In a second very preferred embodiment, the compounds of formulas VIII-1 to VIII-6 are selected from the compounds of formulas VIII-1b to VIII-5b, in particular the compound of formula VIII-2b.

[0223]

Chemical formula

[0224] wherein R 81 , R 82 , L, r, and s have the meanings defined above.

[0225] In a third very preferred embodiment, the compounds of formulas VIII-1 to III-6 are selected from the compounds of formulas III-1c to III-6c, in particular the compound of formula I3-c.

[0226]

Chemical formula

[0227] In the formula, R 1 , R 2 , L, r and s have the meanings defined above.

[0228] In a fourth highly preferred embodiment, the compounds of Formulas VIII-1 to VIII-6 are selected from the compounds of Formulas VIII-1d to VIII-6d, in particular the compounds of Formula VIII-3d.

[0229]

Chemical formula

[0230] In the formula, R 1 , R 2 , L, r and s have the meanings defined above.

[0231] In a particularly preferred embodiment, the medium according to the invention comprises one or more compounds selected from the group of compounds of Formulas VIII-1a to VIII-6a and one or more compounds selected from the group of compounds of Formulas VIII-1b to VIII-6b.

[0232] Very particularly preferably, the medium comprises one or more compounds selected from the group of compounds of Formulas VIII-3a, VIII-2b, VIII-3c and VIII-3d.

[0233]

Chemical formula

[0234] In the formula, R 81 , R 82 , L and r have the meanings defined above, and preferably r is 0.

[0235] The most preferred compounds of Formula VIII include, in particular, one or more of the following.

[0236]

Chemical formula

[0237]

Chem.

[0238]

Chem.

[0239] Alternatively or additionally, compounds of formula VIII below may be used.

[0240]

Chem.

[0241]

Chem.

[0242]

Chem.

[0243] The medium according to the invention optionally contains one or more compounds having negative dielectric anisotropy, preferably selected from the group consisting of formulae Y, B, BC, CR, PH-1 and PH-2.

[0244]

Chem.

[0245] wherein, R Y1 , R Y2 , R B1 , R B2 , R CR1 , R CR2 , R P1 and R P2are each independently of one another an alkyl or alkoxy group having H, 1 to 15 C atoms (in which one or more CH2 groups are arranged such that O atoms are not directly linked to each other,

Chemical formula

Chemical formula

Chemical formula

[0246] The compound of formula Y is preferably selected from the group of compounds of formulae YA, YB, YC and YD.

[0247]

Chemical formula

[0248] In the formula, R 2A , R 2B , R 2C , and R 2D each independently represents H, an alkyl or alkenyl group having up to 15 C atoms, which is unsubstituted, monosubstituted with CN or CF3, or monosubstituted with at least a halogen atom, and further, in the group, one or more CH2 groups are such that O atoms are not directly linked to each other, -O-, -S-,

Chemical formula

[0249] Preferred compounds of formulas YA, YB, YC and YD are shown below.

[0250]

Chemical formula

[0251]

Chemical formula

[0252]

Chemical formula

[0253]

Chemical formula

[0254]

Chemical formula

[0255] [Chemical formula]

[0256] [Chemical formula]

[0257] [Chemical formula]

[0258] [Chemical formula]

[0259] [Chemical formula]

[0260] [Chemical formula]

[0261] [Chemical formula]

[0262] [Chemical formula]

[0263] In the formula, the parameter represents 1 or 2, alkyl and alkyl * each independently represents a linear alkyl group having 1 to 6 carbon atoms, alkenyl represents a linear alkenyl group having 2 to 6 carbon atoms, (O) represents an oxygen atom or a single bond. Alkenyl preferably represents CH2=CH-, CH2=CHCH2CH2-, CH3-CH=CH-, CH3-CH2-CH=CH-, CH3-(CH2)2-CH=CH-, CH3-(CH2)3-CH=CH- or CH3-CH=CH-(CH2)2-.

[0264] Particularly preferred mixtures according to the invention comprise one or more compounds represented by the formulas YA-2, YA-8, YA-10, YA-16, YA-18, YA-40, YA-41, YA-42, YA-43, YB-2, YB-10, YB-16, YC-1, YD-4 and YD-10.

[0265] The proportion of the compounds represented by the formulas YA and / or YB in the total mixture is preferably at least 20% by weight.

[0266] Preferred media according to the invention comprise at least one compound represented by the formula YC-1.

[0267]

Chemical formula

[0268] wherein alkyl and alkyl * have the meanings indicated above and are preferably contained in an amount of <5% by weight, particularly >3% by weight.

[0269] The compounds of formula B are preferably selected from the compounds of formula B-1 and / or B-2.

[0270]

Chemical formula

[0271] wherein the groups occurring have the same meanings as those shown in formula B above and are preferably R 11 and R 12Each is independently an alkyl, alkenyl or alkoxy group having up to 15 carbon atoms, more preferably one or both of them are alkoxy groups, L 11 and L 12 are each preferably F.

[0272] Preferably, the compound of formula B-1 is selected from the group of compounds of formula B-1-1 to B-1-11, preferably formula B-1-6.

[0273]

Chemical formula

[0274]

Chemical formula

[0275] In the formula, alkyl and alkyl * each represent a linear alkyl group having 1 to 6 carbon atoms independently of each other, alkenyl and alkenyl * each represent a linear alkenyl group having 2 to 6 carbon atoms independently of each other, alkoxy and alkoxy * each represent a linear alkoxy group having 1 to 6 carbon atoms independently of each other, and L 1 and L 2 each independently represent F or Cl, preferably both are F.

[0276] Preferably, the compound of formula B-2 is selected from the group of compounds of formula B-2-1 to B-2-10, preferably formula B-2-6.

[0277]

Chemical formula

[0278] [Chemical formula]

[0279] wherein, alkyl and alkyl * each independently represents a linear alkyl group having 1 to 6 carbon atoms, alkenyl and alkenyl * each independently represents a linear alkenyl group having 2 to 6 carbon atoms, alkoxy and alkoxy * each independently represents a linear alkoxy group having 1 to 6 carbon atoms, and L 1 and L 2 each independently represents F or Cl, preferably both are F.

[0280] The medium may contain one or more compounds of formula BA-1 and / or BA-2.

[0281] [Chemical formula]

[0282] wherein, L 11 and L 12 have the same meaning as given by formula B, (O) represents O or a single bond, R IIIA is alkyl or alkenyl having up to 7 carbon atoms or the group Cy-C m H 2m - represents, m and n are the same or different and are 0, 1, 2, 3, 4, 5 or 6, preferably 1, 2 or 3, very preferably 1, Cy represents an alicyclic group having 3, 4 or 5 ring atoms, which may be substituted by alkyl or alkenyl or halogen or CN each having up to 3 C atoms, preferably represents cyclopropyl, cyclobutyl or cyclopentyl.

[0283] The compounds of formula BA-1 and / or BA-2 are contained in the medium, alternatively or additionally preferably additionally, to the compounds of formula B.

[0284] Highly preferred compounds of formula BA-1 and BA-2 are the following.

[0285]

Chemical formula

[0286] In the formula, alkoxy is a linear alkoxy group having 1 to 6 C atoms or alternatively -(CH2) n F (where n is 2, 3, 4 or 5), preferably represents C2H4F.

[0287] Alternatively, the medium contains one or more compounds of formula BAa-1-3.

[0288]

Chemical formula

[0289] In the formula, alkenyl is a linear alkenyl having 2 to 6 C atoms, very preferably represents CH3-CH=CH-CH2-.

[0290] In a preferred embodiment of the invention, the medium contains one or more compounds of formula B-3.

[0291]

Chemical formula

[0292] In the formula, R11 and R 12 are the same or different and are H, alkyl or alkoxy having 1 to 15 C atoms, provided that in these groups, one or more CH2 groups are such that O atoms are not directly linked to each other, -C≡C-, -CF2O-, -OCF2-, -CH=CH-, [Chemical formula] -O-, -CO-O- or -O-CO- and may each be independently replaced by each other, and one or more H atoms in the group may be replaced by halogen.

[0293] The compound of formula B3 is preferably selected from the group of compounds of formula B-3-1 to formula B-3-10.

[0294] [Chemical formula]

[0295] [Chemical formula]

[0296] wherein R 12 is alkyl having 1 to 7 C atoms, preferably ethyl, n-propyl, or n-butyl, or cyclopropylmethyl, cyclobutylmethyl, or cyclopentylmethyl, or -(CH2) n F (n is 2, 3, 4, or 5), preferably represents C2H4F.

[0297] In a preferred embodiment of the present invention, the medium contains one or more compounds of formula B-4 to B-6, preferably a compound of formula B-5.

[0298] [Chemical formula]

[0299] wherein the groups present have the above meanings, and R 11is preferably a linear alkyl, and R 12 is preferably an optionally fluorinated alkoxy, each having 1 to 7 C atoms.

[0300] In a preferred embodiment, the medium comprises one or more compounds of formula I selected from the group of compounds of formulae B-7 to B-9, preferably of formula B-8.

[0301]

Chemical formula

[0302] wherein the parameters have the above meanings, and R 11 is preferably a linear alkyl, and R 12 is preferably F or an optionally fluorinated alkoxy, each having 1 to 7 C atoms.

[0303] Particularly preferred compounds of formulae BC, CR and PH-1 are compounds BC-1 to BC-7, CR-1 to CR-5, and BP-1 to BP-7.

[0304]

Chemical formula

[0305]

Chemical formula

[0306]

Chemical formula

[0307] wherein alkyl and alkyl * each independently represent a linear alkyl group having 1 to 6 C atoms, alkenyl and alkenyl * each independently represent a linear alkenyl group having 2 to 6 C atoms.

[0308] A mixture containing one, two or three compounds of formula BC-2, BC-3, BP-2 and / or BP-3, very preferably BP-2 and / or BP-3, especially BP-3, is more preferred.

[0309] In a preferred embodiment, the medium according to the invention comprises one or more HALS stabilizers of formula H.

[0310]

Chemical formula

[0311] In the formula: Ar represents a methylene group or an aromatic hydrocarbon group having 6 to 40 carbon atoms, a heteroaromatic hydrocarbon group having 4 to 40 carbon atoms, preferably an aromatic hydrocarbon group having 6 to 40 carbon atoms; Sp represents a spacer group; R S represents H, alkyl having 1 to 12 carbon atoms or alkenyl having 2 to 12 carbon atoms; Z S represents -O-, -C(O)O-, -(CH2) z - or -(CH2) z O-, or a single bond; HA is

Chemical formula

[0312] The compound of formula H is preferably selected from formulae H-1, H-2 and H-3.

[0313]

Chemical formula

[0314] wherein R H has the meaning given above and is preferably H or O · represents, Sp, each occurrence being the same or different, represents a spacer group, W represents a straight-chain or branched, optionally unsaturated alkylene having 1 to 12 C atoms, wherein one or more non-adjacent -CH2- groups may be replaced by -O-.

[0315] Preferred compounds of formula H-1 are selected from compounds of formula H-1-1.

[0316]

Chemical formula

[0317] wherein R H has the meaning given above and is preferably H or O · represents, n is an integer from 0 to 12, preferably 5, 6, 7, 8 or 9, very preferably 7.

[0318] Preferred compounds of formula H-2 are selected from compounds of formula H-2-1.

[0319]

Chemical formula

[0320] wherein RH has the meaning given above and preferably represents H or O · and represents n2, which is the same or different at each occurrence, is preferably the same and is an integer from 1 to 12, preferably 2, 3, 4, 5 or 6, very preferably 3, and R S which is the same or different at each occurrence, preferably the same and represents an alkyl having 1 to 6 C atoms, preferably n-butyl.

[0321] Preferred compounds of formula H-3 are selected from formula H-3-1.

[0322]

Chemical formula

[0323] wherein R H has the meaning given above and preferably represents H or O · and represents n is an integer from 0 to 12, preferably 5, 6, 7, 8 or 9, very preferably 7.

[0324] Preferably, the medium of the present invention contains a stabilizer selected from the group of compounds of formulae ST-1 to ST-19.

[0325]

Chemical formula

[0326]

Chemical formula

[0327]

Chemical formula

[0328]

Chemical formula

[0329]

Chem.

[0330]

Chem.

[0331] In the formula, R ST represents H, an alkyl or alkoxy group having 1 to 15 C atoms, provided that in addition, one or more CH2 groups in these groups are arranged such that O atoms are not directly connected to each other, -C≡C-, -CF2O-, -OCF2-, -CH=CH-,

Chem.

Chem.

Chem.

[0332] Among the compounds of formula ST, those particularly selected from the following are particularly preferred:

[0333]

Chem.

[0334]

Chem.

[0335]

Chem.

[0336] A very particularly preferred mixture of the present invention contains one or more stabilizers selected from the group of compounds of formula ST-2a-1, ST-3a-1, ST-3b-1, ST-8-1, ST-9-1 and ST-12.

[0337]

Chem.

[0338]

Chem.

[0339] The compounds of formulas ST-1 to ST-19 are preferably present in the liquid crystal mixture according to the invention, each in an amount of 0.005 to 0.5% based on the mixture.

[0340] When the mixture according to the invention contains two or more compounds from the group of compounds of formulas ST-1 to ST-19, the concentration increases to 0.01 to 1% in the case of two compounds, based on the mixture.

[0341] However, based on the mixture according to the invention, the total proportion of the compounds of formulas ST-1 to ST-19 must not exceed 2%.

[0342] In another preferred embodiment of the invention, the liquid crystal medium further contains one or more polymerizable compounds. The polymerizable compounds are preferably selected from formula M.

[0343]

Chemical formula

[0344] In the formula, the individual groups are the same or different at each occurrence and each independently of one another have the following meanings: R a and R b are P, P-Sp-, H, F, Cl, Br, I, -CN, -NO2, -NCO, -NCS, -OCN, -SCN, SF5 or a linear or branched alkyl having 1 to 25 C atoms, provided that in addition one or more non-adjacent CH2 groups are each independently of one another -C(R 0 )=C(R 00 )-, -C≡C-, -N(R 00 )-, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O- may be replaced, provided that in addition one or more H atoms may be replaced by F, Cl, Br, I, CN, P or P-Sp-, provided that B 1 and / or B 2 contains a saturated C atom, and R a and / or R bmay also represent a group that can be linked to this saturated C atom via a spiro bond, provided that the group R a and R b at least one of which represents or contains the group P or P-Sp-, P is a polymerizable group, Sp is a spacer group or a single bond, B 1 and B 2 are preferably aromatic, heteroaromatic, alicyclic or heterocyclic groups having 4 to 25 ring atoms, and the group may contain a condensed ring, and the group may be unsubstituted or mono- or polysubstituted with L, Z b is -O-, -S-, -CO-, -CO-O-, -OCO-, -O-CO-O-, -OCH2-, -CH2O-, -SCH2-, -CH2S-, -CF2O-, -OCF2-, -CF2S-, -SCF2-, -(CH2) n1 -, -CF2CH2-, -CH2CF2-, -(CF2) n1 -, -CH=CH-, -CF=CF-, -C≡C-, -CH=CH-COO-, -OCO-CH=CH-, -CR 0 R 00 - or a single bond, R 0 and R 00 each independently represents H or alkyl having 1 to 12 C atoms, m represents 0, 1, 2, 3 or 4, n1 represents 1, 2, 3 or 4, L is P, P-Sp-, OH, CH2OH, F, Cl, Br, I, -CN, -NO2, -NCO, -NCS, -OCN, -SCN, -C(=O)N(R x )2, -C(=O)Y 1 , -C(=O)R x , -N(R x)2. It is substituted or unsubstituted silyl, substituted or unsubstituted aryl having 6 to 20 C atoms, or linear or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 25 C atoms, provided that in addition one or more H atoms may be replaced by F, Cl, P or P-Sp-, P and Sp have the meanings shown above, Y 1 represents halogen, R x represents P, P-Sp-, H, halogen, linear, branched or cyclic alkyl having 1 to 25 C atoms (provided that in addition one or more non-adjacent CH2 groups may be replaced by -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O- so that O and / or S atoms are not directly linked to each other, provided that in addition one or more H atoms may be replaced by F, Cl, P or P-Sp-), substituted or unsubstituted aryl or aryloxy group having 6 to 40 C atoms, or substituted or unsubstituted heteroaryl or heteroaryloxy group having 2 to 40 C atoms.

[0345] Preferred compounds of formula I are B 1 and B 2is, in each case independently of one another, 1,4-phenylene, 1,3-phenylene, naphthalene-1,4-diyl, naphthalene-2,6-diyl, phenanthrene-2,7-diyl, 9,10-dihydro-phenanthrene-2,7-diyl, anthracene-2,7-diyl, fluorene-2,7-diyl, coumarin, flavone (provided that one or more CH groups in these groups may be replaced by N), cyclohexane-1,4-diyl (provided that one or more non-adjacent CH2 groups may be replaced by O and / or S), 1,4-cyclohexenylene, bicyclo[1.1.1]pentane-1,3-diyl, bicyclo[2.2.2]octane-1,4-diyl, spiro[3.3]heptane-2,6-diyl, piperidine-1,4-diyl, decahydronaphthalene-2,6-diyl, 1,2,3,4-tetrahydronaphthalene-2,6-diyl, indane-2,5-diyl or octahydro-4,7-methanoindane-2,5-diyl, provided that all of these groups are unsubstituted or may be mono- or polysubstituted by L as defined above.

[0346] Particularly preferred compounds of formula M are B 1 and B 2 which, in each case independently of one another, represent 1,4-phenylene, 1,3-phenylene, naphthalene-1,4-diyl or naphthalene-2,6-diyl.

[0347] Very preferred compounds of formula M are selected from the following formulas.

[0348]

Chemical formula

[0349]

Chemical formula

[0350]

Chemical formula

[0351]

Chem.

[0352]

Chem.

[0353] In the formula, each group, in each occurrence, is the same or different and independently has the following meaning: P 1 、P 2 、P 3 are polymerizable groups, preferably selected from vinyloxy, acrylate, methacrylate, fluoroacrylate, chloroacrylate, oxetane and epoxy, Sp 1 、Sp 2 、Sp 3 is a single bond or a spacer group, provided that in addition one or more groups P 1 -Sp 1 -、P 2 -Sp 2 -and P 3 -Sp 3 -may represent R aa , provided that at least one of the groups P 1 -Sp 1 -、P 2 -Sp 2 -and P 3 -Sp 3 -is different from R aa , preferably -(CH2) p1 -、-(CH2) p1 -O-、-(CH2) p1 -CO-O- or -(CH2) p1 -O-CO-O-, where p1 is an integer from 1 to 12, R aais H, F, Cl, CN or a linear or branched alkyl having 1 to 25 C atoms (provided that in addition one or more non-adjacent CH2 groups are each independently of the other such that O and / or S atoms are not directly linked to each other to form -C(R 0 )=C(R 00 )-, -C≡C-, -N(R 0 )-, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O- and may be replaced, provided that in addition one or more H atoms are F, Cl, CN or P 1 -Sp 1 - and may be replaced. ), particularly preferably a linear or branched alkyl, alkoxy, alkenyl, alkynyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 12 C atoms which may be mono- or polyfluorinated (provided that alkenyl and alkynyl groups have at least 2 C atoms and branched groups have at least 3 C atoms).), R 0 , R 00 is H or an alkyl having 1 to 12 C atoms, R y and R z are H, F, CH3 or CF3, X 1 , X 2 , X 3 is -CO-O-, -O-CO- or a single bond, Z M1 is -O-, -CO-, -C(R y R z )- or -CF2CF2-, Z M2 , Z M3 is -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CF2O-, -OCF2- or -(CH2) n - where n is 2, 3 or 4, L is F, Cl, CN or an alkyl, alkoxy, alkenyl, alkynyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 12 C atoms which may be linear or branched and may be mono-fluorinated or poly-fluorinated, L’ and L” are H, F or Cl, r is 0, 1, 2, 3 or 4, s is 0, 1, 2 or 3, t is 0, 1 or 2, x is 0 or 1.

[0354] Compounds of formula M2 and M13 are highly preferred.

[0355] Trifunctional compounds of formula M15 - M31, especially of formula M17, M18, M19, M22, M23, M24, M25, M30 and M31 are even more preferred.

[0356] In the compounds of formula M1 - M31, [Chemical formula] wherein L has any of the above meanings, r represents 0, 1, 2, 3 or 4, in particular, [Chemical formula]

[0357] wherein L has one of the meanings shown above, identical or different at each occurrence, preferably F, Cl, CN, NO2, CH3, C2H5, C(CH3)3, CH(CH3)2, CH2CH(CH3)C2H5, OCH3, OC2H5, COCH3, COC2H5, COOCH3, COOC2H5, CF3, OCF3, OCHF2, OC2F5 or P-Sp-, very preferably F, Cl, CN, CH3, C2H5, OCH3, COCH3, OCF3 or P-Sp-, more preferably F, Cl, CH3, OCH3, COCH3 or OCF 3、 Most preferably it is F or CH3.

[0358] The preferred compounds of Formulas M1 to M31 are P 1 , P 2 and P 3 represent acrylate, methacrylate, oxetane or epoxy groups, very preferably acrylate or methacrylate groups.

[0359] More preferred compounds of Formulas M1 to M31 are those in which Sp 1 , Sp 2 and Sp 3 are single bonds.

[0360] More preferred compounds of Formulas M1 to M31 are those in which one of Sp 1 , Sp 2 and Sp 3 represents a single bond and the other one of Sp 1 , Sp 2 and Sp 3 is different from a single bond.

[0361] More preferred compounds of Formulas M1 to M31 are those in which the groups Sp 1 , Sp 2 and Sp 3 different from a single bond are -(CH2) s1 -X”- where s1 is an integer from 1 to 6, preferably 2, 3, 4 or 5, and X” is a linkage to a benzene ring and is -O-, -O-CO-, -CO-O-, -O-CO-O- or a single bond.

[0362] An LC medium containing one, two or three types of Formulas M, preferably a polymerizable compound selected from Formulas M1 to M31 is particularly preferred.

[0363] More preferably, the liquid crystal medium of the present invention contains one or more polymerizable compounds selected from Table E below.

[0364] Preferably, the proportion of the polymerizable compound in the liquid crystal medium selected from Formulas M and Table E is 0.01 to 5%, very preferably 0.05 to 1%, and most preferably 0.1 to 0.5%.

[0365] When one or more polymerizable compounds selected from Formula M and Table E are added to a liquid crystal medium, it has been observed that advantageous properties such as fast response time are obtained. Such liquid crystal media are particularly suitable for use in PSA displays and exhibit low image sticking, rapid and complete polymerization, rapid generation of a stable low pretilt angle even after UV irradiation, high reliability, high VHR values after UV irradiation, and high birefringence. By appropriately selecting the polymerizable compound, the absorption of the liquid crystal medium at longer UV wavelengths can be increased, and as a result, it becomes possible to use longer UV wavelengths for polymerization, which is advantageous for the display manufacturing process.

[0366] The polymerizable group P is a group suitable for polymerization reactions such as free radical or ionic chain polymerization, polyaddition or polycondensation, or for polymer-analogous reactions such as addition or condensation onto the polymer main chain. Groups for chain polymerization, particularly those containing a C=C double bond or a C≡C triple bond, and groups suitable for ring-opening polymerization such as oxetane or epoxide groups are particularly preferred.

[0367] Preferred group P is CH2=CW 1 -CO-O-, CH2=CW 1 -CO-,

Chemical formula

[0368] A very preferred group P is CH2=CW 1 -CO-O-, CH2=CW 1 -CO-

Chemical formula

[0369] A very particularly preferred group P is CH2=CW 1 -CO-O-, in particular, CH2=CH-CO-O-, CH2=C(CH3)-CO-O- and CH2=CF-CO-O-, further, CH2=CH-O-, (CH2=CH)2CH-O-CO-, (CH2=CH)2CH-O-,

Chemical formula

[0370] Even more preferred polymerizable groups P are selected most preferably from the group consisting of vinyloxy, acrylate, methacrylate, fluoroacrylate, chloroacrylate, oxetane and epoxide groups, and most preferably from acrylate and methacrylate.

[0371] When Sp is different from a single bond, it is preferably of the formula Sp”-X” such that each group P-Sp- corresponds to the formula R-Sp”-X’-, provided that

[0372] Sp” represents an alkylene having 1 to 20, preferably 1 to 12 C atoms, which group may be mono- or polysubstituted by F, Cl, Br, I or CN, provided that in addition, one or more non-adjacent CH2 groups are each independently of one another -O-, -S-, -NH-, -N(R 0 )-, -Si(R 0 R 00 )-, -CO-, -CO-O-, -O-CO-, -O-CO-O-, -S-CO-, -CO-S-, -N(R 00 )-CO-O-, -O-CO-N(R 0 )-, -N(R 0 )-CO-N(R 00 )-, -CH=CH- or -C≡C- so as not to be replaced by X” is -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O-, -CO-N(R 0 )-, -N(R 0 )-CO-, -N(R 0 )-CO-N(R 00 )-, -OCH2-, -CH2O-, -SCH2-, -CH2S-, -CF2O-, -OCF2-, -CF2S-, -SCF2-, -CF2CH2-, -CH2CF2-, -CF2CF2-, -CH=N-, -N=CH-, -N=N-, -CH=CR 0 -, -CY 2 =CY 3 -., -C≡C-, -CH=CH-CO-O-, -O-CO-CH=CH- or a single bond, R 0 and R00 each independently represents H or an alkyl having 1 to 20 C atoms, Y 2 and Y 3 each independently represents H, F, Cl or CN.

[0373] X” is preferably -O-, -S-, -CO-, -COO-, -OCO-, -O-COO-, -CO-NR 0 -, -NR 0 -CO-, -NR 0 -CO-NR 00 - or a single bond.

[0374] Typical spacer groups Sp and -Sp”-X”- are, for example, -(CH2) p1 -, -(CH2CH2O) q1 -CH2CH2-, -CH2CH2-S-CH2CH2-, -CH2CH2-NH-CH2CH2- or -(SiR 0 R 00 -O) p1 -, where p1 is an integer from 1 to 12 and q1 is an integer from 1 to 3, and R 0 and R 00 have the meanings shown above.

[0375] Particularly preferred spacer groups Sp and -Sp”-X”- are -(CH2) p1 -, -(CH2) p1 -O-, -(CH2) p1 -O-CO-, -(CH2) p1 -CO-O-, -(CH2) p1 -O-CO-O-, provided that p1 and q1 have the meanings shown above.

[0376] Particularly preferred groups "Sp" are linear in each case and are ethylene, propylene, butylene, pentylene, hexylene, heptylene, octylene, nonylene, decylene, undecylene, dodecylene, octadecylene, ethyleneoxyethylene, methylenoxybutylene, ethylenethioethylene, ethylene-N-methyliminoethylene, 1-methylalkylene, ethenylene, propenylene and butenylene.

[0377] In the production of PSA displays, the polymerizable compounds contained in the liquid crystal medium are polymerized or crosslinked (when a compound contains two or more polymerizable groups) in situ in the liquid crystal medium between the substrates of the LC display, optionally while applying a voltage to the electrodes.

[0378] The structure of the PSA display according to the present invention corresponds to the normal shape of the PSA display described in the prior art cited at the beginning. A shape without protrusions is preferred, and in particular, the electrode on the color filter side is not structured, and a shape in which slots are provided only in the electrode on the TFT side is preferred. Preferred electrode structures particularly suitable for PS-VA displays are described, for example, in US2006 / 0066793A1.

[0379] By combining the compounds of the above-mentioned preferred embodiments with the above-mentioned polymer compounds, in the liquid crystal medium according to the present invention, a low threshold voltage, a low rotational viscosity, and very good low-temperature stability can be obtained, and at the same time, a constantly high clearing point and a high VHR value can be obtained.

[0380] By using a liquid crystal medium containing a polymerizable compound, it becomes possible to quickly realize a particularly low pretilt angle in a PSA display. In particular, this liquid crystal medium significantly shortens the response time, particularly the gray-scale response time, in a PSA display compared to the media of the prior art.

[0381] In a further preferred embodiment, the medium according to the present invention contains, alone or in combination with each other, the following compounds, the acronyms of which are explained in Table D below.

[0382] · One or more compounds of formula I in a total concentration in the range of 0.5% to 10%, preferably 1% to 7%, particularly preferably 2% to 5%;

[0383] · One or more compounds of formula II, preferably formula II-1, more preferably sub-formulas II-1a and / or II-1f and / or II-1g and / or II-1h, particularly formula II-1a-1, II-1f-1 and II-1h-1, or formula II-1f-1, II-1g-1 and II-1h-1 in a total concentration in the range of preferably 3% to 20%, preferably 5% to 18%, particularly preferably 7% to 15%;

[0384] and / or · One or more compounds selected from the group of compounds of formula III, preferably formula III-2, more preferably selected from the group of compounds of formula III-2c and / or III-2i and / or III-2l and / or III-2m, very preferably selected from the group of compounds of formula III-2c-4 and / or III-2i-3 and / or III-2l-3 and / or III-2m-1, particularly selected from the group of compounds of formula III-2i-3 and III-2m-1, and the concentration of the compound of formula III-2m-1 is very preferably 1% or less in a total concentration in the range of 0.1% to 10%, preferably 0.2% to 7%, more preferably 0.3% to 2%;

[0385] and / or · One or more compounds of formula YA, preferably formula YA-2 and / or YA-10 in a total concentration in the range of 1% to 10%, preferably 2% to 8%, particularly preferably 3% to 7%;

[0386] and / or · One or more compounds of formula YD, preferably formula YD-7 and / or YD-10 in a total concentration in the range of 1% to 10%, preferably 2% to 8%, particularly preferably 3% to 7%;

[0387] and / or · Compounds of one or more formulas YB, preferably formula YB-2 and / or YB-10, at a total concentration in the range of 0.5% to 10%, preferably 1% to 7%, particularly preferably 2% to 5%;

[0388] and / or · Compounds selected from one or more formulas I, YD, and optionally YA, preferably compounds of formula YA-2, YA-10, YD-7, and YD-10, at a total concentration in the range of 1% to 20%, preferably 3% to 17%, particularly preferably 4% to 14%;

[0389] and / or · Compounds of one or more formulas B, preferably formula B-8, very preferably formula LB(S)-n-OT, particularly LB(S)-3-OT, at a total concentration in the range of 0.1% to 10%, preferably 0.5% to 5%, particularly preferably 1% to 4%;

[0390] and / or · Compounds of one or more formulas IV-1 less than 5%, preferably less than 3%, very preferably less than 1%;

[0391] and / or · Compounds selected from one or more formulas IV, preferably formula IV-3, preferably selected from compounds of formula IV-3-1 to IV-3-6, particularly selected from compounds of formula IV-3-1, IV-3-2, IV-3-4, and IV-3-6, at a total concentration in the range of 20% to 70%, more preferably 30% to 60%, very preferably 33% to 50%;

[0392] and / or · Compound IV-3-6 (CC-3-2V1) or IV-3-4 (CC-4-V1) at a concentration of 0.5% to 8%, preferably 1% to 6%;

[0393] and / or · Compounds of one or more formulas IVa, preferably formula IVa-2, at a total concentration in the range of preferably 0.1% to 3%, more preferably 0.2% to 2%;

[0394] and / or · Preferably, one or more compounds of formula IVb, preferably the compound of formula IVb-2, and very preferably the compound of formula IVb-2-3, at a total concentration in the range of 0.2% to 8%, more preferably 0.5% to 7%, and particularly 1% to 6%;

[0395] and / or · Preferably, one or more compounds of formula V, preferably a compound selected from the group consisting of compounds V-1-1, V-1-6, V-2-1, V-2-2, V-2-3, V-2-4, V-3-4 and V-4-1, at a total concentration in the range of 5% to 50%, preferably 10% to 40%, and particularly 15% to 33%;

[0396] and / or · Preferably, one or more compounds of formula CL, preferably a compound selected from formula CL-3, at a total concentration in the range of 1% to 15%, preferably 2% to 12%, and particularly 3% to 10%;

[0397] and / or · Preferably, one or more compounds of formula V and one or more compounds of formula CL at a total concentration in the range of 5% to 50%, preferably 10% to 40%, and particularly 15% to 33%;

[0398] and / or · Preferably, one or more compounds selected from formula V-1-1 or IV-1-6, preferably compounds CCC-n-V, CCC-V-V and CVCC-n-m, at a total concentration in the range of 0.5% to 10%, preferably 0.75% to 7%, and particularly 1% to 5%;

[0399] and / or · Preferably, one or more compounds of formula V-2-1 and / or V-2-2, preferably CCP-n-m and / or CCP-Vn-m and / or CPP-n-m, and very particularly compounds selected from the group consisting of CCP-3-1, CCP-V-1, and CCP-V2-1, at a total concentration in the range of 8% to 20%, more preferably 12% to 17%, and very preferably 15% to 27%;

[0400] and / or · one or more compounds of formula VII, preferably formula VII-1-20 and / or VII-1-21, in a total concentration preferably in the range of 1% to 15%, preferably 2% to 10%, particularly 3% to 7%;

[0401] and / or · a compound selected from one or more compounds of formula VIII, preferably formula VIII-3, more preferably formula VIII-3a, in a total concentration preferably in the range of 2% to 20%, preferably 5% to 17%, particularly 8% to 14%;

[0402] The liquid crystal medium according to the present invention maintains a nematic phase up to -20 °C, preferably up to -30 °C, particularly preferably up to -40 °C, and keeps the clearing point at 75 °C or higher, preferably 79 °C or higher, while at the same time the rotational viscosity γ 1 can be 80 mPa·s or less, particularly preferably 70 mPa·s or less, and an excellent MLC display with a fast response time can be realized. The rotational viscosity is the value measured at 20 °C.

[0403] The dielectric anisotropy Δη of the liquid crystal medium according to the present invention at 20 °C and 1 kHz is preferably +1.5 or more, preferably in the range of 1.5 to 8, more preferably 2.0 to 6.0, very preferably 2.5 to 4.6, particularly preferably 3.0 to 4.4.

[0404] The birefringence Δη of the liquid crystal medium according to the present invention is preferably 0.080 to 0.140, very preferably 0.090 to 0.135, particularly preferably 0.091 to 0.132.

[0405] In a preferred embodiment of the present invention, the medium has a birefringence of 0.080 to 0.100, very preferably 0.085 to 0.098, particularly 0.090 to 0.094.

[0406] In a preferred embodiment of the present invention, the medium has a birefringence of 0.110 to 0.130, very preferably 0.119 to 0.128, particularly 0.120 to 0.123.

[0407] In a preferred embodiment of the present invention, the medium has a birefringence of 0.120 to 0.140, particularly 0.125 to 0.135, particularly 0.129 to 0.132.

[0408] The rotational viscosity γ of the liquid crystal medium according to the present invention 1 is preferably ≦ 120 mPa·s, more preferably ≦ 110 mPa·s, and very preferably ≦ 105 mPa·s.

[0409] The ratio γ 1 / K1 of the liquid crystal medium according to the present invention is preferably ≦ 5.5 mPa·s / pN, more preferably ≦ 5.3 mPa·s / pN, and very preferably ≦ 5.0 mPa·s / pN.

[0410] In this specification, the structure of the mesogenic compound is represented by abbreviations (also called acronyms). In these abbreviations, the chemical formula is abbreviated as follows using Tables A to C below. All groups C n H 2n+1 C m H 2m+1 and C l H 2l+1 and C n H 2n-1 C m H 2m-1 and C l H 2l-1 are a linear alkyl group or an alkylene group having n, m, and l carbon atoms, respectively, in each case, where n and m are independently 1, 2, 3, 4, 5, 6, or 7, and l is 1, 2, or 3. Table A shows the codes for the ring elements of the nuclear structure of the compound, and Tables B and C show the linking groups and the end groups. Table D shows the structural examples of the compounds and their respective abbreviations.

[0411] <Table A: Ring Elements>

[0412] [Table 1]

[0413] [Table 2]

[0414] <Table B: Crosslinking Group>

[0415]

Table 3

[0416] <Table C: Terminal Group>

[0417]

Table 4

[0418]

Table 5

[0419] In the table, n and m are each integers, and the three dots "..." are places for other abbreviations from this table.

[0420]

[0421]

Table 6

[0422]

Table 7

[0423]

Table 8

[0424]

Table 9

[0425]

Table 10

[0426]

Table 11

[0427]

Table 12

[0428]

Table 13

[0429]

Table 14

[0430]

Table 15

[0431]

Table 16

[0432]

Table 17

[0433]

Table 18

[0434]

Table 19

[0435]

Table 20

[0436]

Table 21

[0437]

Table 22

[0438]

Table 23

[0439]

Table 24

[0440]

Table 25

[0441]

Table 26

[0442]

Table 27

[0443]

Table 28

[0444]

Table 29

[0445]

Table 30

[0446]

Table 31

[0447]

Table 32

[0448]

Table 33

[0449]

Table 34

[0450]

Table 35

[0451]

Table 36

[0452] In a preferred embodiment of the present invention, the medium contains one or more compounds selected from the group of compounds in Table D.

[0453] Table E shows chiral dopants that can preferably be used in the mixtures of the present invention.

[0454]

Table 37

[0455]

Table 38

[0456]

Table 39

[0457] Preferably, the medium according to the present invention contains one or more compounds selected from the group of compounds in Table E.

[0458] Table F shows exemplary reactive mesogenic compounds (RMs) that can be used in the LC medium according to the present invention.

[0459] [Table 40]

[0460] [Table 41]

[0461] [Table 42]

[0462] [Table 43]

[0463] [Table 44]

[0464] [Table 45]

[0465] [Table 46]

[0466] [Table 47]

[0467]

Table 48

[0468]

Table 49

[0469]

Table 50

[0470]

Table 51

[0471]

Table 52

[0472]

Table 53

[0473]

Table 54

[0474]

Table 55

[0475]

Table 56

[0476]

Table 57

[0477]

Table 58

[0478]

Table 59

[0479] In a preferred embodiment, the mixture according to the invention preferably comprises one or more polymerizable compounds selected from the polymerizable compounds of formulae RM-1 to RM-182. Among these, compounds RM-1, RM-4, RM-8, RM-17, RM-19, RM-35, RM-37, RM-39, RM-40, RM-41, RM-48, RM-52, RM-54, RM-57, RM-58, RM-64, RM-74, RM-76, RM-88, RM-91, RM-102, RM-103, RM-109, RM-116, RM-117, RM-120, RM-121, RM-122, RM-139, RM-140, RM-142, RM-143, RM-145, RM-146, RM-147, RM-149, RM-156 to RM-163, RM-169, RM-170 and RM-171 to RM-183 are particularly preferred.

Examples

[0480] The following examples illustrate the invention without limiting the invention. In the examples, m.p. represents the melting point, and T (N,I) represents the clearing point (°C) of the liquid crystal substance. Further, C represents the crystalline solid state, S represents the smectic phase (the subscript represents the type of phase), N represents the nematic phase, Ch represents the cholesteric phase, I represents the isotropic phase, and Tg represents the glass transition temperature. The number between two symbols represents the transition temperature (°C).

[0481] The host mixture used for measuring the optical anisotropy Δn of a single compound is the commercially available mixture ZLI-4792 (Merck KGaA). The dielectric anisotropy Δε was measured using the commercially available mixture ZLI-2857. The physical data of the compound under investigation are obtained from the change in the dielectric constant of the host mixture after adding the compound under investigation and extrapolated to 100% of the compound used. Usually, 10% of the compound under investigation dissolves in the host mixture according to the solubility.

[0482] Unless otherwise specified, parts or percentage data represent parts by weight or percent by weight.

[0483] Above and below V0 is the capacitance threshold voltage [V] at 20°C, n e is the abnormal refractive index at 20°C and 589 nm, n0 is the ordinary refractive index at 20°C and 589 nm, Δn is the optical anisotropy (birefringence) at 20°C and 589 nm, ε ⊥ is the dielectric constant perpendicular to the director at 20°C and 1 kHz, ε ∥ is the dielectric constant parallel to the director at 20°C and 1 kHz, Δε is the dielectric anisotropy at 20°C and 1 kHz, cl.p., T(N,I) is the clearing point [°C], γ1 is the rotational viscosity [mPa·s] at 20°C, K1 is the elastic constant [pN] for the "splay" deformation at 20°C, K2 is the elastic constant [pN] for the "twist" deformation at 20°C, K3 is the elastic constant [pN] for the "bend" deformation at 20°C, K av is K at 20°C av = 1 / 3(1.5K1 + K3) defined as the average elastic constant [pN], LTS indicates the low-temperature stability (nematic phase) determined in the test cell or bulk according to the specification.

[0484] Unless explicitly stated otherwise, all temperature values shown in this application, such as the melting point T(C,N), the transition from the smectic (S) phase to the nematic (N) phase T(S,N), and the clearing point T(N,I) or cl.p., are cited in degrees Celsius (°C).

[0485] For the present invention, unless otherwise specified, the term "threshold voltage" relates to the capacitance threshold (V0), also known as the Frederiks threshold. Also, in the examples, although generally normal, the optical threshold for 10% relative contrast (V 10 ) may also be shown.

[0486] The display used for measuring the capacitance threshold voltage consists of two parallel planar glass outer plates spaced 20 μm apart, each having an electrode layer on the inner side and an unrubbed polyimide alignment layer on the upper side that provides a homeotropic alignment of liquid crystal molecules.

[0487] The display or test cell used for measuring the tilt angle consists of two parallel planar glass outer plates spaced 4 μm apart, each having an electrode layer on the inner side and a polyimide alignment layer on the upper side, provided that the two polyimide layers are rubbed in anti-parallel to each other, resulting in a homeotropic edge alignment of liquid crystal molecules.

[0488] The polymerizable compound is polymerized by irradiating UV light of a specified intensity in the display or test cell for a predetermined time while a voltage is applied to the display (usually, 10 V to 30 V AC, 1 kHz). Unless otherwise indicated in the examples, a metal halide lamp is used for polymerization and irradiated at an illuminance of 100 mW / cm 2 . The illuminance is measured using a standard meter (Hoenle high-end UV meter with UV sensor).

[0489] The tilt angle is determined using a Mueller matrix polarimeter "AxoScan" manufactured by Axometrics. A low value (i.e., a large deviation from the angle of 90°) corresponds to a large tilt.

[0490] Unless otherwise indicated, the term "tilt angle" means the angle between the LC director and the substrate, and "LC director" means the preferential orientation direction of the optical major axis of the LC molecules in the layer of uniformly oriented LC molecules. In the case of calamitic, i.e., uniaxial and positively birefringent LC molecules, "LC director" corresponds to the molecular long axis of the LC molecules.

[0491] Unless otherwise indicated, VHR is measured using a commercially available device, TOYO Corporation, Japan, model LCM-1 (O0004), after heating in an oven at 20 °C (VHR 20 ) and 100 °C for 5 minutes (VHR 100 ). The frequency of the voltage used is in the range of 1 Hz to 60 Hz unless otherwise specified.

[0492] The stability against ultraviolet irradiation is evaluated using a commercially available device “Suntest CPS+” manufactured by Heraeus, Germany, with a xenon lamp NXE1500B. The sealed test cell is irradiated for 2 hours without additional heating unless otherwise specified. The irradiation power in the wavelength range of 300 nm to 800 nm is 765 W / m 2 / V. A UV cut filter with an edge wavelength of 310 nm is used to simulate the so-called window glass mode. In each series of tests, at least 4 test cells are examined for each condition, and each result is shown as the average value of the corresponding individual measured values.

[0493] Normally, the decrease in the voltage holding ratio (ΔVHR) caused by exposure such as ultraviolet irradiation or LCD backlight is determined according to the following formula (1).

Equation

[0494] To examine the low temperature stability (also called LTS), i.e., the stability of the bulk liquid crystal mixture against the natural crystallization of individual components at low temperatures or, in some cases, the emergence of the smectic phase, multiple sealed bottles each containing approximately 1 g of the material are stored at one or more predetermined temperatures (usually -10°C, -20°C, -30°C, and / or -40°C), and the presence or absence of phase transitions is visually inspected regularly. As soon as a change is observed in the first sample at a predetermined temperature, the test is terminated, and the time until the last inspection without any change is recorded as the respective LTS. The test is carried out for 1000 hours. If no change is observed after 1000 hours, the result is "LTS > 1000 hours".

[0495] The ion density used for calculating the resistivity is measured using a VHR test cell with AL16301 polyimide (manufactured by JSR Corporation, Japan) having a cell gap of 3.2 μm, using a commercially available LC material property measurement system model 6254 manufactured by Toyo Technica. The measurement is carried out after leaving it in an oven at 60°C or 100°C for 5 minutes.

[0496] "HTP" represents the helical twisting power (unit: μm) of an optically active substance or a chiral substance in an LC medium. Unless otherwise specified, HTP is measured at 20°C using a commercially available nematic liquid crystal host mixture MLD-6260 (manufactured by Merck KGaA).

[0497] The clearing point is measured using a Mettler thermosystem FP900. The optical anisotropy (Δn) is measured using an Abbe-Refraktometer H005 (sodium spectroscopic lamp Na10, 589 nm, 20°C). The dielectric anisotropy (Δε) is measured using an LCR meter E4980A / Agilent (G005) at 20°C (using an ε parallel cell, JALS2096-R1). The turn-on voltage (V0) is measured using an LCR meter E4980A / Agilent (G005) at 20°C (using an ε parallel cell, JALS2096-R1). The rotational viscosity (γ 1 ) is measured using a TOYO LCM-2 (0002) at 20°C (γ 1Negative cell, measured using JALS-2096-R1. Elastic constant (K 1 , spray) is measured using an LCR meter E4980A / Agilent (G005) at 20 °C (ε parallel cell, using JALS 2096-R1). K3: Elastic constant (K3, bending) is measured using an LCR meter E4980A / Agilent (G005) at 20 °C (ε parallel cell, using JALS 2096-R1).

[0498] Unless otherwise explicitly stated, all concentrations in this application are cited in weight percent and relate to the corresponding mixture consisting of all solid or liquid crystal components without solvent. All physical properties are determined according to "Merck Liquid Crystals, Physical Properties of Liquid Crystals", published in November 1997 by Merck & Co., Inc., Germany, and apply to a temperature of 20 °C unless otherwise explicitly indicated.

[0499] Examples of the following mixtures having positive dielectric anisotropy are particularly suitable for at least one planar alignment layer liquid crystal displays such as, for example, IPS and FFS displays, especially UB-FFS (ultra-high brightness FFS), and VA displays.

[0500] <Example> The compositions and physical properties of comparative mixture C-1 and nematic mixtures M-1 to M-12 are shown in the following table. The compositions are shown in weight percent.

[0501] <Comparative Example C1>

[0502]

Table 60

[0503] <Mixture Example M1>

[0504]

Table 61

[0505] In the following table, the main parameters of mixture C1 and M1 are summarized.

Table 62

[0506] Surprisingly, when the compound CCPC-3-3 of comparative mixture C1 is replaced with the compound CLPC-2-3 of formula I in mixture example 1, a preferably low rotational viscosity (γ 1 ) and at the same time a lower ratio γ 1 / K1 can be achieved, and it has been found that the response time of the display is improved.

[0507] <Mixture Example M2>

[0508]

Table 63

[0509] <Mixture Example M3>

[0510]

Table 64

[0511] <Mixture Example M4>

[0512]

Table 65

[0513] <Mixture Example M5>

[0514]

Table 66

[0515] <Mixture Example M6>

[0516]

Table 67

[0517] <Mixture Example M7>

[0518] Mixture M28 consists of 99.975% of Mixture M1 and 250 ppm of stabilizer ST-3c.

Chemical

[0519] <Mixture Example M8>

[0520] Mixture M29 consists of 99.975% of Mixture M2, 150 ppm of stabilizer ST-3d, and 100 ppm of stabilizer ST-19a.

Chemical

[0521] <Mixture Example M9>

[0522]

Table 68

[0523] <Mixture Example M10>

[0524]

Table 69

[0525] <Mixture Example M11>

[0526]

Table 70

[0527] <Mixture Example M12>

[0528]

Table 71

Claims

1. A liquid crystal medium comprising a) one or more compounds of formula I and b) one or more compounds selected from the group of compounds of formula II and III. 【Chemical 1】 (wherein, R １１ and R １２ are, independently of one another, H, a linear alkyl or alkoxy having 1 to 15 C atoms or a linear alkenyl or alkenyloxy having 2 to 15 C atoms, or a branched alkyl, alkoxy, alkenyl or alkenyloxy each having 3 to 15 C atoms (in the groups one or more CH ２ groups are, independently of one another, such that O atoms are not directly linked to one another 【Chemical 2】 -CH=CH-, -C≡C-, -CF ２ O-, -OCF ２ -, -O-, -CO-O- or -O-CO- and may be substituted, and one or more H atoms in the group may be replaced by a halogen atom.), represents L １１ and L １２ each independently represents H, F, Cl, CH ３ , CF ３ or CHF ２ .) [Chemical Formula 3] (wherein, R ２ and R ３ are, independently of one another, an unsubstituted or halogenated straight-chain or branched alkyl or alkoxy group having 1 to 15 C atoms (in which group one or more CH ２ groups are such that O atoms are not directly linked to one another), [Chemical Formula 4] -C≡C-, -CF ２ O-, -CH=CH-, -O-, -CO-O- or -O-CO- may be substituted. ) represents, 【Chemical 5】 L ２１ 、 L ２２ 、 L ３１ and L ３２ each independently represents H or F, Y ２ and Y ３ are, independently or identically, H or CH ３ and represent X ２ and X ３ each independently represents a halogen, a halogenated alkyl or alkoxy having 1 to 3 C atoms, or a halogenated alkenyl or alkenyloxy having 2 or 3 C atoms, Z ３ represents -CH ２ CH ２ -, -CF ２ CF ２ -, -COO-, trans-CH=CH-, trans-CF=CF-, CH ２ O- or a single bond, and l, m, n and o are, independently of one another, 0 or 1.)

2. L １１ and L １２ is, independently, H or F, the liquid crystal medium according to claim 1.

3. The liquid crystal medium according to claim 1 or 2, wherein the medium comprises one or more compounds of formula II selected from the compounds of formula II-1, II-2 and II-3. [Chemical Formula 6] (wherein, L ２３ and L ２４ represents H or F, and The remaining groups have the meanings given in formula II of claim 1.)

4. The liquid crystal medium according to any one of claims 1 to 3, wherein the medium comprises one or more compounds of formula III selected from the compounds of formula III-1 and III-2. [Chemical Formula 7] (wherein R ３ , X ３ , L ３１ , L ３２ , ring element A ３１ , A ３２ , A ３３ and n and o have the meanings defined in claim 1 of formula III.)

5. The liquid crystal medium according to any one of claims 1 to 4, wherein the medium comprises one or more compounds selected from the group consisting of the compounds of formula Y, B, BC, CR, PH-1 and PH-2. 【Chemical Formula 8】 (wherein, R Ｙ１ , R Ｙ２ , R Ｂ１ , R Ｂ２ , R ＣＲ１ , R ＣＲ２ , R Ｐ１ and R Ｐ２ are each independently H, an alkyl or alkoxy group having 1 to 15 C atoms (in which one or more CH ２ The group is such that the O atoms are not directly linked to each other. 【Chemical Formula 9】 -CH=CH-, -C≡C-, -CF ２ O-, -OCF ２ -,-O-,-CO-O- or -O-CO- and may be substituted, and one or more H atoms in the group may be replaced by a halogen atom.), and 【Chemical Formula 10】 are, independently of one another in each occurrence, a) a 1,4-cyclohexenylene or 1,4-cyclohexylene group, in which one or two non-adjacent CH ２ groups may be replaced by -O- or -S-. b) a 1,4-phenylene group (wherein one or two CH groups in the group may be replaced by N), or c) a group from the group of spiro[3.3]heptane-2,6-diyl, 1,4-bicyclo[2.2.2]octylene, naphthalene-2,6-diyl, decahydronaphthalene-2,6-diyl, 1,2,3,4-tetrahydronaphthalene-2,6-diyl, phenanthrene-2,7-diyl and fluorene-2,7-diyl, provided that the groups a), b) and c) may be mono- or polysubstituted by halogen atoms, Z ｘ 、Z ｙ is the same as or different from, -CH ２ CH ２ -, -CH=CH-, -CF ２ O-, -OCF ２ -, -CH ２ O-, -OCH ２ -, -COO-, -OCO-, -C ２ F ４ -, -CF=CF-, -CH=CHCH ２ O- or represents a single bond, Z １ is, independently of each other at each occurrence, -CO-O-, -O-CO-, -CF ２ O-, -OCF ２ -, -CH ２ O-, -OCH ２ -, -CH ２ -, -CH ２ CH ２ -, -(CH ２ ) ４ -, -CH=CH-CH ２ O-, -C ２ F ４ -, -CH ２ CF ２ -, -CF ２ CH ２ -, -CF=CF-, -CH=CF-, -CF=CH-, -CH=CH-, -C≡C- or a single bond, L Y１ 、L Y２ 、L B１ and L B２ each independently represents F, Cl, CF ３ or CHF ２ and represents Y represents H, F, Cl, CF ３ , CHF ２ or CH ３ and W represents O or S, n is 0, 1 or 2, c is 0, 1 or 2, x and y are independently 0, 1 or 2, where x + y ≤ 3.)

6. The liquid crystal medium according to any one of claims 1 to 5, wherein the medium comprises one or more compounds of formula VII. 【Chemical 11】 (wherein, R ７１ and R ７２ represent H, F, a linear alkyl or alkoxy having 1 to 15 C atoms, a linear alkenyl or alkenyloxy having 2 to 15 C atoms or a branched alkyl, alkoxy, alkenyl or alkenyloxy having 3 to 15 C atoms, provided that in these groups one or more CH ２ groups are arranged such that O atoms are not directly linked to each other 【Chemical Formula 12】 -C≡C-, -CF ２ O-, -OCF ２ -,-CH=CH-,-O-,-CO-O- or -O-CO-, each of which may be independently replaced with one another, and one or more H atoms in the group may be replaced with halogen, X ７１ 、X ７２ 、X ７３ 、X ７４ 、X ７５ and X ７６ represent, either the same or different, H or F, and Z ７１ and Z ７２ are the same or different and represent CH ２ CH ２ or a single bond. )

7. The liquid crystal medium according to any one of claims 1 to 6, wherein the medium comprises one or more compounds of formula IV. 【Chemical 13】 (wherein, R １１ represents a linear alkyl group having 1 to 12 carbon atoms, a branched or cyclic alkyl group having 3 to 12 carbon atoms, or a linear alkenyl group having 2 to 12 carbon atoms or a branched alkenyl group having 3 to 12 carbon atoms or a cyclic alkenyl group having 5 to 12 carbon atoms, and one or more H atoms in the group may optionally be replaced by fluorine, R １２ represents a linear alkyl or alkoxy group having 1 to 12 carbon atoms, a branched or cyclic alkyl or alkoxy group having 3 to 12 carbon atoms, or a linear alkenyl group having 2 to 12 carbon atoms or a branched alkenyl group having 3 to 12 carbon atoms or a cyclic alkenyl group having 5 to 12 carbon atoms, and one or more H atoms in the group may be optionally replaced by fluorine.

8. The liquid crystal medium according to any one of claims 1 to 7, wherein the medium comprises one or more compounds of formula IVa and / or IVb. 【Chemical Formula 14】 (wherein, R ４１ and R ４２ each independently represents a linear alkyl, alkoxy, alkenyl, alkoxyalkyl, or alkenyloxy group having up to 12 carbon atoms, 【Chemical Formula 15】 represents, Z ４ is a single bond, -CH ２ CH ２ -, -CH=CH-, -CF ２ O-, -OCF ２ -, -CH ２ O-, -OCH ２ -, -COO-, -OCO-, -C ２ F ４ -, -C ４ H ８ - or -CF=CF-.

9. The liquid crystal medium according to any one of claims 1 to 8, wherein the medium comprises one or more compounds of formula V. 【Chemical 16】 (wherein, R ５１ and R ５２ represent alkyl having 1 to 7 carbon atoms, alkoxy having 1 to 7 carbon atoms, alkoxyalkyl having 2 to 7 carbon atoms, alkenyl or alkenyloxy, 【Chemical 17】 represents, Z ５１ and Z ５２ each independently represents -CH ２ -CH ２ -, -CH ２ -O-, -CH=CH-, -C≡C-, -COO- or a single bond, and n is 1 or 2.)

10. The liquid crystal medium according to any one of claims 1 to 9, wherein the medium comprises one or more compounds of formula VIII. 【Chemical 18】 (wherein, R ８１ and R ８２ are the same or different and represent H, halogen, CN, SCN, a linear alkyl or alkoxy having 1 to 15 C atoms, a linear alkenyl or alkenyloxy having 2 to 15 C atoms or a branched alkyl, alkoxy, alkenyl or alkenyloxy having 3 to 15 C atoms, provided that one or more CH ２ groups in these groups are such that O atoms are not directly linked to each other, 【Chemical Formula 19】 -C≡C-, -CF ２ O-, -OCF ２ -,-CH=CH-,-O-,-CO-O- or -O-CO-, each of which may be independently replaced with one another, and one or more H atoms in the group may be replaced with halogen; A ０ 、 A ８１ and A ８２ are each, independently of one another, phenylene-1,4-diyl (in which one or two CH groups in the group may be replaced by N, and one or more H atoms are halogen, CN, CH ３ , CHF ２ , CH ２ F, CF ３ , OCH ３ , OCHF ２ or OCF ３ and may be replaced by). cyclohexane-1,4-diyl (in which one or two non-adjacent CH ２ groups may each independently be replaced by O and / or S, and one or more H atoms may be replaced by F). cyclohexene-1,4-diyl, bicyclo[1.1.1]pentane-1,3-diyl, bicyclo[2.2.2]octane-1,4-diyl, spiro[3.3]heptane-2,6-diyl, tetrahydropyran-2,5-diyl or 1,3-dioxane-2,5-diyl; Z ８１ and Z ８２ each independently represents —CF ２ O—, —OCF ２ —, —CH ２ O—, —OCH ２ —, —CO—O—, —O—CO—, —C ２ H ４ —, —C ２ F ４ —, —CF ２ CH ２ —, —CH ２ CF ２ —, —CFHCFH—, —CFHCH ２ —, —CH ２ CFH—, —CF ２ CFH—, —CFHCF ２ —, —CH═CH—, —CF═CH—, —CH═CF—, —CF═CF—, —C≡C— or a single bond; n represents 0, 1, 2 or 3, and m represents 0, 1, 2 or 3.)

11. A liquid crystal display comprising the liquid crystal medium according to any one of Claims 1 to 10.

12. The liquid crystal display according to Claim 11, wherein the display is configured to operate in an IPS mode or an FFS mode.

13. The compound of Formula I. 【Chemical 20】 (Wherein, R １１ and R １２ are, independently of one another, H, straight-chain alkyl or alkoxy having 1 to 15 C atoms or straight-chain alkenyl or alkenyloxy having 2 to 15 C atoms, or branched alkyl, alkoxy, alkenyl or alkenyloxy each having 3 to 15 C atoms (in the groups one or more CH ２ groups, independently of one another, such that O atoms are not directly linked to one another) 【Chemical Formula 21】 -CH=CH-, -C≡C-, -CF ２ O-, -OCF ２ -, -O-, -CO-O- or -O-CO- and may be substituted, and one or more H atoms in the group may be replaced by halogen.), represents L １１ and L １２ represent H, F, Cl, CH ３ , CF ３ or CHF ２ , and neither L １１ nor L １２ represents H, and when one of L １１ and L １２ represents F, the other of L １１ and L １２ is not Cl.)

14. A method for producing the compound of Formula I according to Claim 13, comprising a step of removing water from at least the compound of Formula (3). 【Chemical 22】 (Wherein, R １１ 、 R １２ 、 L １１ and L １２ have the meaning of formula I according to claim 13.

15. The compound of Formula (3) as defined in Claim 14.

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