LCD Media

Abstract

A liquid crystal medium is provided. The present invention relates to liquid crystal (LC) media and liquid crystal displays (LCDs) containing these media, in particular energy-saving displays addressed by active matrix, in particular 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 displays. The media have improved long-term stability at low temperatures, making them highly suitable for automotive and outdoor applications.

Description

[Technical Field]

[0001] The present invention relates to liquid crystal (LC) media and liquid crystal displays (LCDs) containing these media, in particular energy-saving displays addressed by active matrix, in particular 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 displays. The media have improved low-temperature stability (LTS) and high long-term stability against UV radiation and high temperatures. [Background technology]

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

[0003] In addition to these modes, there is also an electro-optical mode that utilizes an electric field substantially parallel to the substrates and the liquid crystal layer. For example, International Publication No. 91 / 10936 (Patent Document 1) discloses a liquid crystal display in which the electric signal is generated so that the electric field has a component parallel to the liquid crystal layer, which has since become known as an in-plane switching (IPS) display. The operating principle of such a display is described, for example, in RA Soref, Journal of Applied Physics, Vol. 45, No. 12, pp. 5466-5468 (1974) (Non-Patent Document 1).

[0004] IPS displays contain an LC layer between two planarly arranged substrates, with two electrodes located on only one of the substrates, preferably in an interdigitated configuration. When a voltage is applied to the electrodes, an electric field is generated between the electrodes with a significant component parallel to the LC layer, which causes a reorientation of the LC molecules in the plane of the layer.

[0005] EP 0 588 568 A1 discloses, for example, various possibilities for designing electrodes and addressing IPS displays. DE 198 24 137 A1 likewise describes various embodiments of such IPS displays.

[0006] Liquid crystal materials for this type of IPS display are described, for example, in DE 195 28 104 A1.

[0007] Furthermore, so-called "fringe-field switching" (FFS) displays have been reported (see, in particular, SH Jung et al., Jpn. J. Appl. Phys., Vol. 43, No. 3, 2004, p. 1028 (Non-Patent Document 2)), which comprise two electrodes on the same substrate, one of which is structured like a comb and the other unstructured. This generates strong so-called "fringe fields", i.e., a strong electric field near the edge of the electrode and an electric field with both a strong vertical component and a strong horizontal component throughout the cell. FFS displays have a small viewing angle dependence of their contrast. FFS displays typically comprise an LC medium with positive dielectric anisotropy and an alignment layer, usually a polyimide, which provides a planar alignment to the molecules of the LC medium.

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

[0009] Further improvements have been achieved with the HB-FFS mode, which, in contrast to conventional FFS technology, allows for higher transmission and allows the panel to operate with less energy consumption.

[0010] Another recently developed mode is the XB-FFS mode, in which the liquid crystal medium additionally contains polar liquid crystal compounds with low dielectric anisotropy.

[0011] Liquid crystal compositions suitable for LCDs, particularly FFS and IPS displays, are known, for example, from JP 07-181439 A (Patent Document 5), EP 0 667 555 B (Patent Document 6), EP 0 673 986 B (Patent Document 7), DE 195 09 410 B (Patent Document 8), DE 195 28 106 B (Patent Document 9), and DE 195 28 107 B (Patent Document 10). However, these compositions have certain drawbacks. Among other defects, most of them result in undesirably long address times, have inadequate values ​​of resistivity, and / or require excessively high operating voltages. Herein, improvements are needed in both operating characteristics and shelf life.

[0012] FFS and IPS displays can be operated as active-matrix displays (AMD) or passive-matrix displays (PMD). In the case of active-matrix displays, individual pixels are typically addressed by integrated non-linear active elements such as thin-film transistors (TFT), while in the case of passive-matrix displays, individual pixels are typically addressed by multiplexing methods as known from the prior art.

[0013] The displays according to the invention are preferably with an active matrix, preferably a TFT matrix, but the liquid crystals according to the invention can also be used to advantage in displays with other known addressing means.

[0014] Typical applications for in-plane switching (IPS) and fringe field switching (FFS) technologies are monitors, laptops, televisions, mobile phones, tablet PCs, etc.

[0015] Both IPS and FFS technologies have certain advantages over other LCD technologies, such as vertical alignment (VA) technologies, such as a wide viewing angle dependence of contrast.

[0016] The provision of further liquid crystal media and their use in displays with high transmittance, good black state and high contrast ratio is a central issue for modern FFS and IPS applications. In addition, modern applications also require good low temperature stability and fast address times.

[0017] Matrix liquid crystal (MFK) displays with full-array LED backlighting have become increasingly common in recent years and contain a large number of light-emitting diodes (LEDs) directly behind a layer with an MFK medium. Modern high-performance InGaN LEDs can reach operating temperatures of over 70°C and, depending on the design, can emit UV radiation as well as visible light. Direct contact between the LED and the LC medium therefore places special demands on the UV stability and temperature resistance of the LC medium. Therefore, state-of-the-art MFK displays do not meet today's requirements.

[0018] In recent years, MFK displays have increasingly been used for outdoor applications, such as public information displays (PIDs) that display various information in stations, roads, airports, hotels, and shopping malls. Compared to conventional MFK displays for television applications, PIDs require much higher long-term resistance to ultraviolet light from the sun and high temperatures, as well as a wider operating temperature range. Furthermore, because such displays are commonly exposed to temperatures as low as -20°C, they also require adequate low-temperature stability (LTS) and a wide nematic phase range. Due to the lack of suitable LC media, display types with relatively high power consumption have been used for such applications. [Prior art documents] [Patent documents]

[0019] [Patent Document 1] International Publication No. 91 / 10936 [Patent Document 2] European Patent No. 0 588 568 [Patent Document 3] DE 198 24 137 A1 [Patent Document 4] DE 195 28 104 A1 [Patent Document 5] Japanese Patent Application Publication No. 07-181439 [Patent Document 6] European Patent No. 0 667 555 [Patent Document 7] European Patent No. 0 673 986 [Patent Document 8] German Patent No. 195 09 410 [Patent Document 9] German Patent No. 195 28 106 [Patent Document 10] German Patent No. 195 28 107 [Patent Document 11] International Publication No. 2010 / 099853 [Patent Document 12] DE 10 2010 027 099 [Patent Document 13] Japanese Patent Application Publication No. 1-240592 [Non-patent literature]

[0020] [Non-Patent Document 1] RA Soref, Journal of Applied Physics, Vol. 45, No. 12, pp. 5466-5468 (1974) [Non-patent document 2] SHJung et al., Jpn.J.Appl.Phys., Volume 43, No. 3, 2004, Page 1028 Summary of the Invention [Problem to be solved by the invention]

[0021] The present invention has the object of providing a liquid-crystalline medium, particularly for FFS and IPS displays, but also for TN, transparent displays, positive VA or STN displays, and in particular for active matrix displays, such as those addressed by TFT, which does not exhibit the above-mentioned disadvantages or exhibits them to a lesser extent, and preferably has high resistivity, low threshold voltage, high dielectric anisotropy, good low temperature stability (LTS), a wide nematic phase range, fast response time and low rotational viscosity, excellent long-term stability against UV radiation and elevated operating temperatures, and allows high brightness. In other words, such an LC medium should be suitable for outdoor use in energy-saving LC displays.

[0022] This has been achieved by providing a liquid crystal medium as described and claimed hereinafter.

[0023] For FFS displays, response time, contrast, brightness and reliability need to be further optimized, however it has been found that prior art liquid crystal materials often do not achieve all these requirements simultaneously.

[0024] Surprisingly, it has been found that liquid-crystalline media according to the invention comprising a combination of one or more compounds of formula I with at least one compound of formula T1 and / or T2 exhibit several improvements, in particular when used in FFS mode displays, such as good solubility, excellent LTS values, a wide nematic phase range and a low ratio of γ1 / K1, allowing fast response times.

[0025] The liquid-crystalline media according to the invention are particularly suitable for use in liquid-crystal displays of the FFS, HB-FFS, XB-FFS and IPS mode based on dielectrically positive liquid crystals and their polymer-stabilized modifications.

[0026] Prior art, such as WO 2010 / 099853 and DE 10 2010 027 099 A1, disclose thiophene-containing LC media. WO 2010 / 099853 teaches compounds containing a thiophene-2,5-diyl unit directly linked to a 2- and / or 6-substituted-1,4-phenylene unit. WO 2010 / 099853 describes the development of new materials for use in LC displays. This objective was achieved by providing compounds of the following general formula:

[0027] [ka]

[0028] In the formula, A 0 represents a 2,6-difluoro-1,4-phenylene unit, and A 1 and A 2 represents, among other meanings, a 1,4-phenylene or 1,4-cyclohexylene unit, and Z 1 and Z 2 represents a bridging element or a single bond.

[0029] Specific examples described include the following compounds (see International Publication No. 2010 / 099853 (Patent Document 11)).

[0030] [ka]

[0031] For many practical applications in liquid crystal displays, known liquid crystal media containing thiophene compounds have only moderate LTS. Exposure to temperatures below -20 °C generally leads to the formation of undesirable smectic phases. In particular, liquid crystal media containing large amounts of diluents, such as CC-3-V and CC-3-V1, in addition to thiophene compounds often have insufficient LTS and are therefore unsuitable for use at low temperatures.

[0032] JP-A-1-240592 (Patent Document 13) describes a liquid crystal composition for TN and STN applications that has a wide nematic phase range and contains, inter alia, a tolan compound of the following structure:

[0033] [ka]

[0034] This document does not mention diluents or mesogenic thiophene compounds such as CC-3-V or CC-3-V1. [Means for solving the problem]

[0035] A subject of the invention is a liquid-crystalline medium, characterized in that it comprises one or more compounds of formula I

[0036] [ka]

[0037] wherein the individual groups have the following meanings: R 1 and R 2 are each independently an H atom, an alkyl or alkoxy group having 1 to 12 C atoms, or an alkenyl or alkenyloxy group having 2 to 12 C atoms (in which one or more non-adjacent CH groups are connected in such a way that O atoms are not directly linked to each other, such as -C≡C-, -CF2O-, -OCF2-, -CH=CH-, [ka] -O-, -CO-O- or -O-CO-, in which one or more H atoms may be replaced by halogen atoms), or a cycloalkyl or cycloalkoxy group having 3 to 12 C atoms, in which one or more H atoms may be replaced by halogen atoms, Y 0is an H atom, an alkyl group having 1 to 3 C atoms, or an alkenyl group having 2 to 3 C atoms (in which one or more non-adjacent CH groups may be replaced by -C≡C-, -CF2O-, -OCF2-, -CH=CH-, -O-, -CO-O- or -O-CO- in such a way that O atoms are not directly linked to one another), A 0 , A 1 , A 2 each independently represent phenylene-1,4-diyl (with the proviso that in addition, one or two CH groups 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 (with the proviso that in addition, one or two non-adjacent CH2 groups may be replaced independently 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 1 and Z 2 represent, independently of one another, -CF2O-, -OCF2-, -C2O-, -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; k and l each independently represent 0, 1, 2 or 3;

[0038] In addition to one or more compounds of formula I as defined above, the medium comprises one or more compounds selected from formulae T1 and T2.

[0039] [ka]

[0040] During the ceremony, [ka] [ka] R 3 and R 4 are each independently an alkyl or alkoxy group having 1 to 12 C atoms or an alkenyl group having 2 to 12 C atoms (in which one or more CH groups are connected in such a way that O atoms are not directly linked to each other, such as -C≡C-, -CF2O-, -OCF2-, -CH=CH-, [ka] and -O-, -CO-O-, or -O-CO-, in which one or more H atoms may be replaced by halogen atoms. L 1~6 each independently represents H or F; X 0 represents F, Cl, CN, SF5, SCN, NCS, a halogenated alkyl group or a halogenated alkoxy group having 1 to 6 C atoms, or a halogenated alkenyl group or a halogenated alkenyloxy group having 2 to 6 C atoms, Y 1~3 each independently represents H, a linear or branched alkyl or alkoxy group having 1 to 6 C atoms, or a cycloalkyl or cycloalkoxy group having 3 to 6 C atoms, m and n each independently represent 0 or 1.

[0041] The present invention further relates to the use of a liquid-crystalline medium as described above and below for electro-optical purposes, in particular for use in liquid crystal displays, shutter glasses, LC windows, 3D applications, preferably in TN, PS-TN, STN, TN-TFT, OCB, IPS, PS-IPS, FFS, HB-FFS, XB-FFS, PS-HB-FFS, PS-XB-FFS, SA-HB-FFS, SA-XB-FFS, polymer-stabilized SA-HB-FFS, polymer-stabilized SA-XB-FFS, positive-VA and positive-PS-VA displays, very preferably in LCoS, FFS, HB-FFS, IPS, PS-HB-FFS and PS-IPS displays.

[0042] The present invention further relates to electro-optical liquid crystal displays, in particular TN, PS-TN, STN, TN-TFT, OCB, IPS, PS-IPS, FFS, HB-FFS, XB-FFS, PS-HB-FFS, PS-XB-FFS, SA-HB-FFS, SA-XB-FFS, polymer-stabilized SA-HB-FFS, polymer-stabilized SA-XB-FFS, positive-VA or positive-PS-VA displays, transparent displays, preferably FFS, HB-FFS, IPS, PS-HB-FFS or PS-IPS displays, comprising a liquid-crystalline medium as described above and below. DETAILED DESCRIPTION OF THE INVENTION

[0043] In this application, all atoms also include their isotopes. In a preferred embodiment, one or more hydrogen atoms (H) are replaced with deuterium (D), the high degree of deuteration enabling or simplifying analytical determination of the compound, especially at low concentrations.

[0044] In the above and below equations, R 1 , R 2 , R 3 , R 4 or R 0where R preferably represents an alkyl and / or alkoxy group, this may be linear or branched. 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, further methyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, methoxy, octyloxy, nonyloxy, decyloxy, undecyloxy, dodecyloxy, tridecyloxy or tetradecyloxy. 0 preferably denotes a straight-chain alkyl having 2 to 6 C atoms.

[0045] Oxaalkyl preferably represents straight-chain 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.

[0046] R 1 , R 2 , R 3 , R 4 or R 0 When represents an alkoxy or oxaalkyl group, it may also contain one or more additional oxygen atoms, provided that the oxygen atoms are not directly linked to one another.

[0047] In another preferred embodiment, one or more R 1 , R 2 , R 3 , R 4 or R 0 teeth, [ka] -S 1-F, -OS 1 -F, -O-S1-O-S2 (in the formula, S 1 is C 1~12 -Alkylene or C 2~12 -alkenylene, and S 2 is H, C 1~12 -Alkyl or C 2~12 -alkenyl), and very preferably one or more R 1 , R 2 , R 3 , R 4 or R 0 teeth, [ka] Selected from the group consisting of: -OCH2OCH3, -O(CH2)2OCH3, -O(CH2)3OCH3, -O(CH2)4OCH3, -O(CH2)2F, -O(CH2)3F, -O(CH2)4F.

[0048] R 1 , R 2 , R 3 , R 4 or R 0 represents an alkyl group in which one CH2 group is replaced by -CH=CH-, this may be linear or branched. It is preferably linear and has 2 to 10 C atoms. It therefore stands in particular for 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.

[0049] R 1 , R 2 , R 3 , R 4 or R 0When is an alkyl or alkenyl group at least monosubstituted with a halogen, the group is preferably linear and the halogen is preferably F. In the case of polysubstitution, the halogen is preferably F. The resulting group also includes perfluoro groups. In the case of monosubstitution, the fluorine or chlorine substituent may be in any desired position, but is preferably in the ω-position.

[0050] In the above and below equations, X 0 is preferably CN, SCN, NCS, 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. 0 is particularly preferably CN, CF3, CHF2, OCF3, OCHF2, OCFHCF3, OCFHCHF2, OCFHCHF2, OCF2CH3, OCF2CHF2, OCF2CHF2, OCF2CF2CHF2, OCF2CF2CHF2, OCFHCF2CF3, OCFHCF2CHF2, OCF2CF2CF3, OCH=CF2 or CH=CF2, very particularly preferably F or OCF3, furthermore CF3, OCF=CF2, OCHF2 or OCH=CF2.

[0051] In the LC media according to the invention, the use of compounds of formula I in combination with one or more compounds selected from the formulae T1 and T2, preferably in combination with compounds of the formulae Z1 to Z8 or their sub-formulae, leads to high LTS values, ε ⊥ Increased values ​​of K and a simultaneous reduction in rotational viscosity and the ratios γ1 / K2 and γ1 / K1 make it possible to achieve fast response times. LC media are therefore highly suitable for automotive applications such as navigation systems and various instrument clusters.

[0052] Compound of Formula I A 0Preference is given to LC media comprising compounds of formula I, in which A represents phenylene-1,4-diyl, in which additionally one or two CH groups may be replaced by N and one or more H atoms may be replaced by halogen, CN, CH3, CHF2, CH2F, OCH3, OCHF2, CF3 or OCF3. 0 but [ka] More preferably, A 0 but [ka] and very particularly preferably represents [ka]

[0053] Preferred compounds of formula I result in media with particularly high clearing points, low rotational viscosities, broad nematic phases, high birefringence and good thermal and UV stability.

[0054] Further preferred are compounds of formula I in which k and l are 0, 1 or 2, particularly preferably 0 or 1. Particularly preferred are compounds of formula I in which l is 0, i.e. the thiophene ring is a terminal ring. Further preferred are compounds of formula I in which k is 0, 1 or 2, preferably 1 or 2, very particularly preferably 1.

[0055] In Formula I, A 0 , A 1 and A 2 particularly preferably denotes phenylene-1,4-diyl (which radicals may also be mono- or polysubstituted by F), furthermore cyclohexane-1,4-diyl, cyclohexenylene-1,4-diyl, tetrahydropyran-2,5-diyl or 1,3-dioxane-2,5-diyl.

[0056] Z in Formula I 1 and Z 2particularly preferably represents -CF2O-, -OCF2- or a single bond, with a single bond being particularly preferred.

[0057] A in Formula I 1 and A 2 is particularly preferably [ka] Preferably, it represents unsubstituted 1,4-phenylene, in which L represents halogen, CF3 or CN, preferably F.

[0058] R 1 and R 2 are each independently H, F, Cl, Br, —CN, —SCN, —NCS, SF5, halogen or alkyl, alkenyl or alkynyl having up to 8, preferably up to 5, C atoms, each of which may be substituted by halogen, in particular F.

[0059] Particularly preferred groups R in formula I 1 and R 2 represents H, halogen or alkyl, alkenyl, alkynyl or alkoxy having up to 12, preferably up to 8, C atoms, each of which may be substituted by halogen, in particular F, with H, F, alkyl, alkenyl or alkynyl having up to 8 C atoms being particularly preferred. Preferably at least one group is not H, particularly preferably the group R 1 and R 2 Both of these are not H. 1 is very particularly preferably equal to alkyl. 2 is more preferably H, alkyl or fluorine. Very particularly preferably R 1 is alkyl, and R 2 is H or alkyl. R 1 , R 2 R each independently very particularly preferably represents unbranched alkyl having 1 to 5 C atoms. 1 and R 2represents a substituted alkyl, alkoxy, alkenyl or alkynyl, two groups R 1 and R 2 The total number of C atoms in is preferably less than 10.

[0060] Preferred alkyl groups are for example methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl and n-octyl.

[0061] Preferred alkenyl groups are for example ethenyl, propenyl, butenyl and pentenyl.

[0062] Preferred alkynyl groups are for example ethynyl, propynyl, butynyl, pentynyl, hexynyl, heptynyl and octynyl.

[0063] Preferred alkoxy groups are for example methoxy, ethoxy, n-propoxy, n-butoxy, n-pentoxy, n-hexoxy, n-heptoxy, n-octoxy.

[0064] Halogen preferably represents F or Cl, with F being most preferred.

[0065] Particularly preferred compounds of formula I are those selected from the following subformulae:

[0066] [ka]

[0067] [ka]

[0068] In the formula, Y 0 , R 1 and R 2 has the meaning given in general formula I, L 1 ~L 6 independently represent H or F, where R 1 and R2 preferably represents optionally fluorinated alkyl or alkoxy having 1 to 12 C atoms, optionally fluorinated alkenyl or alkynyl having 2 to 12 C atoms, or optionally fluorinated cycloalkyl having 3 to 12 C atoms. Y 0 is preferably an H atom or a methyl group.

[0069] Particularly preferred is optionally fluorinated alkyl, alkenyl or alkynyl having up to 5 C atoms. 2 preferably represents F. In formulas I-1-4 to I-1-6, L 3 and L 4 preferably represents H. In formulas I-1-4 to I-1-6, L 3 and L 4 preferably represents F.

[0070] In particularly preferred embodiments, the compound of formula I is selected from the following structures:

[0071] [ka]

[0072] In the formula, R 1 has the same meaning as in general formula I, and R 2 represents a linear or branched alkyl or alkoxy group having 1 to 7 C atoms, or an alkenyl, alkenyloxy, or alkoxyalkyl group having 2 to 7 C atoms, or a cycloalkyl or cycloalkoxy group having 3 to 12 C atoms, in which one or more non-adjacent CH groups are arranged in such a way that O atoms are not directly linked to each other, such as -C≡C-, -CF2O-, -OCF2-, -CH=CH-, [ka] may be substituted with -O-, -CO-O- or -O-CO-, in which one or more H atoms may be replaced by halogen atoms; Y0 represents an H atom or a linear or branched alkyl group having 1 to 3 C atoms.

[0073] LC media according to the invention having particularly high LTS, a wide nematic phase range, high long-term stability to UV radiation and high temperatures and low rotational viscosity are obtained with the following compounds of the general formula I:

[0074] [ka]

[0075] [ka]

[0076] [ka]

[0077] [ka]

[0078] [ka]

[0079] [ka]

[0080] [ka]

[0081] [ka]

[0082] In the formula, Y 0 , R 1 and R2 is as defined above.

[0083] In addition, particular preference is given to LC media which comprise compounds of formula I below:

[0084] [ka]

[0085] [ka]

[0086] [ka]

[0087] The most preferred compounds of formula I especially include one or more of the following:

[0088] [ka]

[0089] [ka]

[0090] [ka]

[0091] As a further possibility, compounds of formula I below can be used:

[0092] [ka]

[0093] [ka]

[0094] [ka]

[0095] As a further possibility, compounds of formula I below can be used:

[0096] [ka]

[0097] [ka]

[0098] [ka]

[0099] [ka]

[0100] Compounds of formula I can be prepared analogously to methods known to those skilled in the art and described in standard works of organic chemistry such as, for example, Houben-Weyl, Methoden der organischen Chemie [Methods of Organic Chemistry], Thieme-Verlag, Stuttgart.

[0101] <Compounds of formula T1 and T2> Preferably, the one or more compounds of formula T1 and T2 are selected from the group consisting of compounds of the following formulae:

[0102] [ka]

[0103] [ka]

[0104] During the ceremony, R 3 and R 4 are each independently an alkyl or alkoxy group having 1 to 6 C atoms or an alkenyl group having 2 to 6 C atoms (in which one or more CH groups are connected in such a way that O atoms are not directly linked to each other, such as -C≡C-, -CF2O-, -OCF2-, -CH=CH-, [ka] and -O-, -CO-O-, or -O-CO-, in which one or more H atoms may be replaced by halogen atoms. L 1 and L 2 each independently represents H or F; X 0 represents CN, SCN, NCS or a halogenated alkyl group having 1 to 6 carbon atoms, Y 1 and Y 2 each independently represents H, a linear or branched alkyl or alkoxy group having 1 to 6 C atoms, or a cycloalkyl or cycloalkoxy group having 3 to 6 C atoms, preferably H or CH3.

[0105] The substituent R in formula I 3 and R 4 The selection of R is not particularly limited. 3 and R 4 It is particularly advantageous to choose an alkyl or cycloalkyl group of up to 6 C atoms as R 3 and R 4 It is particularly preferred that Y is selected from the group consisting of methyl, ethyl, n-propyl, i-propyl, n-butyl, s-butyl, i-butyl, and cyclopentyl. 0 may be represented by a CH3 group.

[0106] In particularly preferred embodiments, compounds of general formula T1 and T2 can be represented by either:

[0107] [ka]

[0108] [ka]

[0109] [ka]

[0110] During the ceremony, R 3 represents an alkyl group having 1 to 6 C atoms (in which one or more CH groups are not directly linked to O atoms, such as -C≡C-, -CF2O-, -OCF2-, [ka] -O-, -CO-O- or -O-CO-, in which one or more H atoms may be replaced by halogen atoms), preferably an alkyl group having 1 to 4 C atoms, an alkenyl group or alkenyloxy group having 2 to 6 C atoms, or a cycloalkyl group or cycloalkyloxy group having 3 to 6 C atoms, particularly preferably a vinyl group, an allyl group or a cyclopentyl group, Y 1 represents H or CH3, preferably H, m represents 1, 2, 3 or 4.

[0111] In the present invention, the use of compounds of sub-formula T1-1a is advantageous over the use of T1-1b in terms of the low-temperature stability of the resulting LC media.

[0112] Highly preferred compounds of formula T1 are those selected from the group consisting of the following subformulae: [ka]

[0113] [ka]

[0114] [ka]

[0115] [ka]

[0116] [ka]

[0117] In the formula, Y 1 is H or CH3, preferably H.

[0118] Highly preferred compounds of formula T2 are those selected from the group consisting of the following subformulae:

[0119] [ka]

[0120] In the formula, Y 1 is H or CH3, preferably H.

[0121] The LC media according to the invention preferably contain 1 to 20% by weight, more preferably 2 to 15% by weight, particularly preferably 3 to 10% by weight, of compounds of the general formulae T1 and / or T2.

[0122] <Additional Ingredients> Preferably, the LC medium comprises, in addition to one or more compounds of the formula I and T1 and / or T2, one or more compounds selected from the following formulae:

[0123] [ka]

[0124] [ka]

[0125] During the ceremony, "Alkyl" and "alkyl * " are C 1~6 - alkyl, preferably ethyl, propyl, butyl or pentyl, very preferably ethyl, propyl or butyl, "alkenyl" and "alkenyl * " is preferably C 2~6 -represents alkenyl. Compounds of formula Z1 and Z2 are highly preferred.

[0126] Preferred compounds of formulae Z1 to Z11 are those selected from the following sub-formulae:

[0127] [ka]

[0128] [ka]

[0129] In another preferred embodiment the medium comprises one or more compounds of formula Z1 or the preferred sub-formulae thereof and / or one or more compounds selected from formulae Z2, Z3, Z4 and Z5 or the preferred sub-formulae thereof.

[0130] Preferably, the total proportion of compounds of formulae Z1, Z2, Z3, Z4, Z5 and Z6 or their subformulae CC-3-V in the medium is 10-65% by weight, very preferably 20-60% by weight, most preferably 25-55% by weight. In an even more preferred embodiment, compounds of formula Z1-1 are used in a concentration range of 10% to 60% by weight, more preferably 25% to 50% by weight, based on the total weight of the LC medium. In a further preferred embodiment, the LC medium comprises a total of 50% to 70% by weight of compounds of formulae Z1-1 and Z4-2.

[0131] Preferably the LC medium comprises one, two or three compounds selected from the formulae Z1, Z2, Z3 and Z4 or sub-formulae thereof.

[0132] The LC medium may additionally comprise one or more compounds of the following general formula:

[0133] [ka]

[0134] During the ceremony, R 1 and R 2 are each independently of each other, C 1~6 -Alkyl, C 1~6 -alkoxy or C 2~6 - represents alkenyl.

[0135] Compounds of formula XII are preferably selected from the following sub-formulae:

[0136] [ka]

[0137] In the formula, "alkyl" and "alkyl * " are each independently methyl, butyl, pentyl or hexyl.

[0138] Compounds of formula XIIa and formula XIIc are particularly preferred. In formula XIIb, "alkyl" is preferably, independently of each other, n-C3H7, n-C4H9 or n-C5H 11 In formula XIIc, "alkyl" preferably represents n-C3H7, and "alkyl * " preferably represents CH3 or n-C3H7.

[0139] Particularly preferred compounds of formula XIIa are represented by the following structure:

[0140] [ka]

[0141] The LC medium may additionally comprise one or more compounds selected from the following formulae:

[0142] [ka]

[0143] In the formula, L 1 and L 2 has the meaning shown in formula T1, and R 1 and R 2 each independently of one another denotes n-alkyl, alkoxy, oxaalkyl, fluoroalkyl or alkenyl, each having up to 6 C atoms, preferably each independently of one another denotes alkyl having 1 to 6 C atoms; in compounds of formula XIV at least one group R 1 and R 2 preferably denotes alkenyl having 2 to 6 C atoms.

[0144] The LC medium further comprises at least one group R 1 and R 2 represents alkenyl having 2 to 6 C atoms, preferably those selected from the following sub-formulae:

[0145] [ka]

[0146] In the formula, "alkyl" and "alkyl * " have the meaning given above and each independently of one another preferably denote methyl, ethyl or propyl.

[0147] Compounds of formula XIV are preferably selected from the following sub-formulae:

[0148] [ka]

[0149] Compounds of formulae XIVd1, XIVe-1, XIVe-2 and XIVe-3 are highly preferred.

[0150] In a still further embodiment the LC medium may comprise one or more compounds of formula XVI

[0151] [ka]

[0152] In the formula, R 1 and R 2 have the meanings given in formula I and preferably each independently denote alkyl having 1 to 6 C atoms. L denotes H or F.

[0153] Particularly preferred compounds of formula XVI are those of the following subformula:

[0154] [ka]

[0155] During the ceremony, "Alkyl" and "alkyl *" each independently represent a straight-chain alkyl group having 1 to 6 C atoms, in particular ethyl, propyl or pentyl, and "alkenyl" and "alkenyl * " each independently represent a straight-chain alkenyl group having 2 to 6 C atoms, in particular CH2=CHC2H4, CH3CH=CHC2H4, CH2=CH and CH3CH=CH.

[0156] Particular preference is given to compounds of the formulae XVIb and XVIc: Very particular preference is given to compounds of the following subformulae:

[0157] [ka]

[0158] Compounds of formula XVIc2 are highly preferred.

[0159] In a further preferred embodiment, the LC medium comprises one or more compounds of the following formulae:

[0160] [ka]

[0161] During the ceremony, R 1 and R 2 have the meanings given in formula I and preferably each independently denote alkyl having 1 to 6 C atoms. L denotes H or F.

[0162] Compounds of formula XVIIa where L is H and compounds of formula XVIIb where L is F are highly preferred.

[0163] The LC medium may further comprise one or more compounds of the following formulae:

[0164] [ka]

[0165] During the ceremony, L, R 1 and R 2 are the L in the formula Y, respectively. 1 , R 1 and R 2 R 1 and R 2 preferably denotes alkyl, alkoxy, oxaalkyl, fluoroalkyl or alkenyl, each having up to 6 C atoms.

[0166] In a further preferred embodiment, the LC medium may comprise one or more compounds selected from the formulae XXXIVa and XXXIVb.

[0167] [ka]

[0168] During the ceremony, The individual radicals are the same or different at each occurrence and each, independently of the others, have the following meanings: R 0 represents an alkyl group having 1 to 12 carbon atoms or an alkenyl group having 2 to 12 carbon atoms (in which one or more CH groups are not directly linked to each other by O atoms, such as -C≡C-, -CF2O-, -OCF2-, -CH=CH-, [ka] and -O-, -CO-O-, or -O-CO-, in which one or more H atoms may be replaced by halogen atoms. R 2 represents an alkyl group having 1 to 6 C atoms or an alkenyl group having 2 to 6 C atoms (in which one or more CH groups are not directly linked to O atoms, such as -C≡C-, -CF2O-, -OCF2-, -CH=CH-, [ka] and -O-, -CO-O-, or -O-CO-, in which one or more H atoms may be replaced by halogen atoms. L 1 and L 2 is H, F or Cl, Y 0 is H or CH3.

[0169] [ka]

[0170] During the ceremony, The individual radicals are the same or different at each occurrence and each, independently of the others, have the following meanings: R 0 represents an alkyl group having 1 to 12 carbon atoms or an alkenyl group having 2 to 12 carbon atoms (in which one or more CH groups are not directly linked to each other by O atoms, such as -C≡C-, -CF2O-, -OCF2-, -CH=CH-, [ka] and -O-, -CO-O-, or -O-CO-, in which one or more H atoms may be replaced by halogen atoms. X 2 is an F atom, an alkyl or alkoxy group having 1 to 6 C atoms in which one or more H atoms are replaced by an F atom, or an alkenyl or alkenyloxy group having 2 to 6 C atoms, preferably F, CF3 or OCF3, L 1 and L 2 is H, F or Cl, Y 0 is H or CH3.

[0171] In particularly preferred embodiments, compounds of general formula XXXIVa and XXXIVb may be represented by either:

[0172] [ka]

[0173] During the ceremony, R 0 represents an alkyl group having 1 to 12 C atoms (in which one or more CH groups are not directly linked to O atoms, such as -C≡C-, -CF2O-, -OCF2-, [ka] -O-, -CO-O- or -O-CO-, in which one or more H atoms may be replaced by halogen atoms), preferably an alkyl group having 1 to 4 C atoms, an alkenyl group or alkenyloxy group having 2 to 6 C atoms, or a cycloalkyl group or cycloalkyloxy group having 3 to 6 C atoms, particularly preferably a vinyl group, an allyl group or a cyclopentyl group, n represents 1, 2, 3, 4 or 5; m represents 1, 2, 3 or 4.

[0174] The compounds of the formula XXXIV, in particular of the formula XXXIVa, are preferably used in the LC media according to the invention in amounts of 0.5 to 10% by weight, particularly preferably 1 to 5% by weight.

[0175] In a further embodiment, the LC medium may comprise one or more compounds of the following formula:

[0176] [ka]

[0177] In the formula, R 1 and R 2 has the meaning given for the compounds of formula I. Preferably, R 1 represents an alkyl or alkenyl having 1 to 6 or 2 to 6 carbon atoms, respectively, and R 2 represents alkenyl having 2 to 6 C atoms.

[0178] Preferred compounds of formula XXXV include, in particular: [ka] is.

[0179] In the formula, "alkyl" represents an alkyl group having 1 to 6 C atoms.

[0180] In yet another embodiment, the LC medium may comprise one or more compounds of the following formulae:

[0181] [ka]

[0182] In the formula, R 1 and R 2 have the meanings indicated in formula I and preferably each independently represent alkyl having 1 to 6 C atoms.

[0183] The LC medium may furthermore comprise one or more compounds selected from the following formulae:

[0184] [ka]

[0185] In the formula, the individual radicals each independently have the following meanings at each occurrence, which may be the same or different: [ka] R 0 is R in formula I 1 is one of the meanings given to X 0 is F, Cl, a halogenated alkyl group, a halogenated alkenyl group, a halogenated alkoxy group or a halogenated alkenyloxy group having up to 6 C atoms, Y 1~6 is H or F, Y 0 is H or CH3.

[0186] Preferred compounds of formula II and III are 0 is a compound where

[0187] Further preferred compounds of formula II and III are those in which R 0 is alkyl having 1 to 6 C atoms, particularly preferably ethyl or propyl, and X 0 is F or OCF3, particularly preferably F.

[0188] In a preferred embodiment, the LC medium comprises one or more compounds of formula II selected from the following sub-formulae:

[0189] [ka]

[0190] [ka]

[0191] In the formula, R 0 and X 0 has the meaning indicated in formula II.

[0192] Preferred compounds are those represented by formulae II-1, II-2 and II-3, and particularly preferred are those represented by formulae II-1 and II-2.

[0193] In the compounds represented by formulae II-1 to II-7, R 0 is preferably alkyl having 1 to 6 carbon atoms, particularly preferably ethyl or propyl, and X 0 is preferably F or OCF3, and particularly preferably F.

[0194] In a further preferred embodiment, the LC medium comprises one or more compounds of formula II or of its sub-formulae as defined above and below, and Y 0 is CH3, and very preferably the medium according to this preferred embodiment comprises one or more compounds of formula II selected from the following sub-formulae:

[0195] [ka]

[0196] [ka]

[0197] In the formula, R 0 and X 0 has the meaning indicated in formula II.

[0198] Preferred compounds are those represented by formulae IIA-1, IIA-2 and IIA-3, and particularly preferred are those represented by formulae IIA-1 and IIA-2.

[0199] In the compounds of formulae IIA-1 to IIA-7, R 0 is preferably alkyl having 1 to 6 carbon atoms, particularly preferably ethyl or propyl, and X 0 is preferably F or OCF3, and particularly preferably F.

[0200] In a further preferred embodiment, the LC medium comprises one or more compounds of formula III selected from the following sub-formulae:

[0201] [ka]

[0202] [ka]

[0203] [ka]

[0204] [ka]

[0205] In the formula, R 0 and X 0 has the meaning indicated in formula II.

[0206] Preferred compounds are those represented by formulae III-1, III-4, III-6, III-16, III-19 and III-20.

[0207] In the compounds of formulae III-1 to III-21, R 0 preferably denotes alkyl having 1 to 6 C atoms, very preferably ethyl or propyl, and X 0 preferably represents F or OCF3, very preferably F, and Y 2 preferably represents F.

[0208] In yet another embodiment, the LC medium comprises one or more compounds of formula III or sub-formulae thereof as defined above and below, wherein Y 0 is CH3. Very preferably, the LC medium according to this preferred embodiment comprises one or more compounds of formula III selected from the following sub-formulae: [ka]

[0209] [ka]

[0210] [ka]

[0211] [ka]

[0212] In the formula, R 0 and X 0 has the meaning shown in formula III.

[0213] Preferred compounds are those represented by formulae IIIA-1, IIIA-4, IIIA-6, IIIA-16, IIIA-19 and IIIA-20.

[0214] In the compounds of formulae IIIA-1 to IIIA-21, R 0 preferably denotes alkyl having 1 to 6 C atoms, particularly preferably ethyl or propyl, and X 0 preferably represents F or OCF3, particularly preferably F, and Y 2 preferably represents F.

[0215] In a further embodiment, the LC medium further comprises one or more compounds selected from the following formulae:

[0216] [ka]

[0217] During the ceremony, R 0 , X 0 , Y 0 and L 1-5 has the meaning given in formulas II and III, Z 0 represents -C2H4-, -(CH2)4-, -CH=CH-, -CF=CF-, -C2F4-, -CH2CF2-, -CF2CH2-, -CHO-, -OCH2-, -COO-, -CF2O-, or -OCF2-, and in formulas V and VI also represents a single bond; r represents 0 or 1; s represents 0 or 1.

[0218] The compound of formula IV is preferably selected from the following formulae:

[0219] [ka]

[0220] In the formula, R 0 and X 0 has the meaning given in formulas II and III.

[0221] R 0 preferably represents alkyl having 1 to 6 carbon atoms. 0 preferably represents F or OCF3, furthermore OCF=CF2 or Cl.

[0222] The compounds of formula IVa are preferably represented by the following sub-formula:

[0223] [ka]

[0224] The compounds of formula IVb are preferably represented by the following sub-formula:

[0225] [ka]

[0226] The compounds of formula IVc are preferably represented by the following sub-formula:

[0227] [ka]

[0228] In the formula, R 0 has the meaning given in formula II and is preferably propyl or pentyl.

[0229] The compounds of the formula IVc, in particular of the formula IVc-1, are preferably used in the LC media according to the invention in an amount of 1 to 20% by weight, particularly preferably 2 to 15% by weight.

[0230] The compounds of formula V are preferably selected from the following sub-formulae:

[0231] [ka]

[0232] [ka]

[0233] In the formula, R 0 and X 0 has the meaning given in formula II.

[0234] R 0 preferably denotes alkyl having 1 to 6 C atoms. 0 preferably represents F and OCF3, furthermore OCHF2, CF3, OCF=CF2 and OCH=CF2.

[0235] The compounds of formula VI are preferably selected from the following sub-formulae:

[0236] [ka]

[0237] In the formula, R 0 and X 0 has the meaning given in formula II.

[0238] R 0 preferably represents alkyl having 1 to 6 C atoms. 0 preferably represents F, furthermore OCF3, CF3, CF=CF2, OCHF2 and OCH=CF2.

[0239] The compounds of formula VII are preferably selected from the following sub-formulae:

[0240] [ka]

[0241] In the formula, R 0 and X 0 has the meaning given in formula II.

[0242] R 0 preferably denotes alkyl having 1 to 6 C atoms. 0 preferably represents F, furthermore OCF3, OCHF2, and OCH=CF2.

[0243] In some embodiments, the LC medium further comprises one or more compounds selected from the following formulae:

[0244] [ka]

[0245] [ka]

[0246] During the ceremony, R 0 and X 0 each independently of one another has the meaning given in formula II, L 1~4 each independently represents H or F; Y 0 represents H or CH3, preferably H, X 0 preferably represents F, Cl, CF3, OCF3 or OCHF2, R 0 preferably denotes alkyl, alkoxy, oxaalkyl, fluoroalkyl or alkenyl, each having up to 6 C atoms.

[0247] The LC media according to the invention very preferably comprise one or more compounds of the formula XXa.

[0248] [ka]

[0249] In the formula, R 0 is R in Formula I 1 It has the same meaning as R 0 is preferably straight-chain alkyl, in particular ethyl, n-propyl, n-butyl or n-pentyl, very preferably n-propyl.

[0250] The compounds of the formula XX, in particular of the formula XXa, are preferably used in the LC media according to the invention in an amount of 0 to 15% by weight, particularly preferably 1 to 10% by weight.

[0251] Very preferably, the LC media according to the invention comprise one or more compounds of the formula XXIa.

[0252] [ka]

[0253] In the formula, R 0 is R in Formula I 1 It has the same meaning as R 0 is preferably straight-chain alkyl, in particular ethyl, n-propyl, n-butyl or n-pentyl, very preferably n-propyl.

[0254] The compounds of the formula XXI, in particular of the formula XXIa, are preferably used in the LC media according to the invention in an amount of 1 to 15% by weight, particularly preferably 2 to 10% by weight.

[0255] More preferably, the LC media according to the invention comprise one or more compounds of the formula XXIIIa.

[0256] [ka]

[0257] In the formula, R 0 is R in Formula I 1 It has the same meaning as R 0 is preferably a straight chain alkyl group, in particular ethyl, n-propyl, n-butyl or n-pentyl, very preferably n-propyl.

[0258] The compounds of the formula XXIII, in particular of the formula XXIIIa, are preferably used in the LC media according to the invention in an amount of 0.5 to 5% by weight, particularly preferably 0.5 to 2% by weight.

[0259] The LC medium may furthermore comprise one or more compounds of formula XXIV.

[0260] [ka]

[0261] During the ceremony R 0 , X 0 and L 1-6 has the meaning given in formula III, s represents 0 or 1, and [ka]

[0262] In formula XXIV, X 0 may represent an alkyl group having 1 to 6 C atoms or an alkoxy group having 1 to 6 C atoms. The alkyl group or alkoxy group is preferably linear.

[0263] R 0 preferably represents an alkyl group having 1 to 6 carbon atoms. 0 preferably represents F.

[0264] The compounds of formula XXIV are preferably selected from the following sub-formulae:

[0265] [ka]

[0266] [ka]

[0267] During the ceremony, R 0 , X 0 and L 1 has the meaning given in formula III. 0 preferably represents alkyl having 1 to 6 C atoms. 0 preferably represents F, L 1 preferably represents F. [ka]

[0268] R 0 is a straight chain alkyl or alkenyl having 2 to 6 carbon atoms.

[0269] The LC medium may further comprise one or more compounds of the following formulae:

[0270] [ka]

[0271] During the ceremony, R 1 and X 0 are R shown in Formula II, respectively. 0 and X 0 R 1 preferably represents alkyl having 1 to 6 C atoms. 0 preferably represents F or Cl. In formula XXIV, X 0 particularly preferably represents Cl.

[0272] The LC medium may furthermore comprise one or more compounds of the following formulae:

[0273] [ka]

[0274] During the ceremony, R 1 and X 0 are R shown in Formula II, respectively. 1 and X 0 R 1 preferably represents alkyl having 1 to 6 C atoms. 0 preferably denotes F. The media according to the invention particularly preferably contain X 0 preferably represents F.

[0275] The compounds of the formulae XXVI to XXIX are preferably used in the LC media according to the invention in amounts of 1 to 20% by weight, particularly preferably 1 to 15% by weight. Particularly preferred LC media comprise at least one compound of the formula XXIX.

[0276] Very preferably, the LC medium according to the invention comprises one or more compounds of the formula XXIXa.

[0277] [ka]

[0278] During the ceremony, R 1 has the meaning given in formula I and preferably denotes straight-chain alkyl, in particular ethyl, n-propyl, n-butyl or n-pentyl, particularly preferably n-propyl.

[0279] The compounds of the formula XXIXa are preferably used in the LC media according to the invention in an amount of 1 to 15% by weight, particularly preferably 2 to 10% by weight.

[0280] The LC medium may further comprise one or more pyrimidine or pyridine compounds of the following formulae:

[0281] [ka]

[0282] During the ceremony, R 1 and X 0 are R in Formula II, respectively. 0 and X 0 R 1 preferably denotes alkyl having 1 to 6 C atoms. 0 preferably denotes F. The medium according to the invention particularly preferably comprises one or more compounds of the formula XXX-1, in which X 0 preferably denotes F. The compounds of the formulae XXX-1 to XXX-3 are used in the LC media according to the invention preferably in amounts of 1 to 20% by weight, particularly preferably 1 to 15% by weight.

[0283] In one preferred embodiment according to the invention, the LC medium comprises one or more compounds selected from the formulae Y and B in addition to the compounds of the formulae I and T1 and / or T2.

[0284] [ka]

[0285] In the formula, the individual radicals, which are identical or different at each occurrence, each have the following meaning independently of one another: [ka] [ka] [ka] R 1 , R 2 is R in Formula I1 and R 2 is one of the meanings given to R 3 is R 1 is one of the meanings given to Z x , Z y is —CH2CH2—, —CH═CH—, —CF2O—, —OCF2—, —CHO—, —OCH2—, —CO—O—, —O—CO—, —C2F4—, —CF═CF—, —CH═CH—CHO— or a single bond, preferably a single bond, Z z is -CH2O-, -O-, -C2H4-, -OCH2-, or a single bond Y 1 is -CH2-, -O- or -S-, L 1~4 is H, F or Cl, preferably H or F, very preferably F, x and y are 0, 1, or 2, provided that x+y is 3 or less; z is 0 or 1, with the proviso that in Formula B the dibenzofuran or dibenzothiophene group may also be further substituted with methyl or methoxy groups; provided that the compound of formula Y contains at least one substituent L which is F or Cl, preferably F. 1~4 Includes.

[0286] Preferably, the LC medium according to this first preferred embodiment comprises one or more compounds of formula I, T1 and / or T2, one or more compounds selected from formulae Z1, Z2 and Z3, and one or more compounds selected from formulae Y and B.

[0287] The LC medium according to this first preferred embodiment is particularly suitable for use in LC displays in the HB-FFS or PS-HB-FFS mode, as well as in transparent displays.

[0288] In compounds of formula Y and its subformulas, R 1 and R 2preferably denotes straight-chain alkyl or alkoxy having 1 to 6 C atoms, furthermore alkenyl having 2 to 6 C atoms, in particular vinyl, 1E-propenyl, 1E-butenyl, 3-butenyl, 1E-pentenyl, 3E-pentenyl or 4-pentenyl.

[0289] In the compounds of formula Y and its sub-formulas, the group L 1 and L 2 and both represent F. In another preferred embodiment of the invention, in the compounds of formula Y and its sub-formulas, the group L 1 and L 2 One of them represents F and the other represents Cl.

[0290] In a further preferred embodiment of the invention the LC medium comprises one or more compounds of formula Y which are selected from the following sub-formulae:

[0291] [ka]

[0292] In the formula, L 1 , L 2 , R 1 , R 2 , Z x , Z y , x and y have the meanings given in formula Y or one of the preferred meanings given above in formula I, a represents 1 or 2, b represents 0 or 1; [ka] L 3 , L 4 represents F or Cl, preferably F, and L 5 represents an H atom or CH3.

[0293] Preferably, the formula Y 1 and Y 2 In the compound of 1 and L 2Both of these represent F, or L 1 and L 2 One of them represents F and the other represents Cl, or L 3 and L 4 Both of these represent F, or L 3 and L 4 One of them represents F and the other represents Cl.

[0294] Preferably the LC medium comprises one or more compounds of the formula Y1 selected from the group consisting of the following subformulae:

[0295] [ka]

[0296] [ka]

[0297] [ka]

[0298] [ka]

[0299] [ka]

[0300] [ka]

[0301] [ka]

[0302] [ka]

[0303] [ka]

[0304] [ka]

[0305] [ka]

[0306] [ka]

[0307] [ka]

[0308] [ka]

[0309] During the ceremony, a represents 1 or 2, "Alkyl" and "alkyl * " each independently represent a linear alkyl group having 1 to 6 carbon atoms, "alkenyl" denotes a linear alkenyl group having 2 to 6 carbon atoms, and L 5 represents an H atom or CH3.

[0310] "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-.

[0311] Very preferably, the LC medium comprises one or more compounds of formula Y1 selected from formulae Y1-1, Y1-2, Y1-7, Y1-12, Y1-17, Y1-22, Y1-40, Y1-41, Y1-42, Y1-44, Y1-50 and Y1-68. 5 preferably represents an H atom.

[0312] More preferably, the LC medium comprises one or more compounds of formula Y2 selected from the group consisting of the following subformulae:

[0313] [ka]

[0314] [ka]

[0315] [ka]

[0316] [ka]

[0317] [ka]

[0318] [ka]

[0319] [ka]

[0320] During the ceremony, "Alkyl" and "alkyl *" each independently represent a linear alkyl group having 1 to 6 carbon atoms, "alkenyl" denotes a linear alkenyl group having 2 to 6 C atoms, and (O) denotes an oxygen atom or a single bond, and L 5 represents an H atom or CH3, preferably an H atom.

[0321] "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-.

[0322] Very preferably, the LC medium comprises one or more compounds of formula Y2 selected from formulae Y2-2 and Y2-10.

[0323] The proportion of compounds of the formula Y1 or any subformula thereof in the LC medium is preferably between 0 and 10% by weight.

[0324] The proportion of compounds of the formula Y2 or any subformula thereof in the LC medium is preferably between 0 and 10% by weight.

[0325] The total proportion of compounds of the formulae Y1 and Y2 or their subformulae in the LC medium is preferably 1-20% by weight, very preferably 2-15% by weight.

[0326] Preferably the LC medium comprises one, two or three compounds selected from the formulae Y1 and Y2 or sub-formulae thereof, very preferably from the formulae Y1-2, Y1-22, Y1-66, Y1-70, Y2-6 and Y2-22.

[0327] In another preferred embodiment of the invention the LC medium comprises one or more compounds of formula Y which are selected from the following sub-formulae:

[0328] [ka]

[0329] In the formula, L 1 , L 2 , R 1 and R 2 has one of the meanings given in formula Y or one of the preferred meanings as given in formula I and its sub-formulas.

[0330] Preferred compounds of formula Y3 are selected from the group consisting of the following subformulae:

[0331] [ka]

[0332] [ka]

[0333] [ka]

[0334] During the ceremony, "Alkyl" and "Alkyl * " each independently represent a linear alkyl group having 1 to 6 carbon atoms, "Alkenyl" and "Alkenyl * " each independently represent a straight-chain alkenyl group having 2 to 6 C atoms, and O represents an oxygen atom or a single bond.

[0335] "Alkenyl" and "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-.

[0336] Particularly preferred compounds of formula Y3 are selected from the group consisting of the following subformulae:

[0337] [ka]

[0338] In the formula, "Alkoxy" and "Alkoxy * " each independently of one another preferably denotes straight-chain alkoxy having 3, 4 or 5 C atoms.

[0339] Preferably in the compounds of formula Y3 and its subformulas, L 1 and L 2 and both represent F. More preferably, in compounds of formula Y3, the group L 1 and L 2 One of them represents F and the other represents Cl.

[0340] The proportion of compounds of the formula Y3 or any subformula thereof in the LC medium is preferably between 1 and 10% by weight, very preferably between 1 and 6% by weight.

[0341] Preferably the LC medium comprises one, two or three compounds of the formula Y3 or a subformula thereof, preferably of the formula Y3-6, very preferably of the formula Y3-6A.

[0342] In another preferred embodiment of the invention the LC medium comprises one or more compounds of formula Y selected from the sub-formulae Y4.

[0343] [ka]

[0344] R in the formula 1 and R 2 each independently of one another has one of the meanings given above in formula Y, [ka] L in the ceremony5 represents F or Cl, preferably F, and L 6 represents F, Cl, OCF3, CF3, CH3, CH2F or CHF2, preferably F, and preferably at least one of the rings G, I and K is different from unsubstituted benzene.

[0345] Preferred compounds of formula Y4 are selected from the group consisting of the following subformulae:

[0346] [ka]

[0347] [ka]

[0348] [ka]

[0349] During the ceremony, R represents a linear alkyl or alkoxy group having 1 to 7 C atoms, R * represents a linear alkenyl group having 2 to 7 carbon atoms, (O) represents an oxygen atom or a single bond, and m represents an integer of 1 to 6;

[0350] R * 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-.

[0351] R preferably represents methyl, ethyl, propyl, butyl, pentyl, hexyl, methoxy, ethoxy, propoxy, butoxy or pentoxy.

[0352] The proportion of compounds of the formula Y4 or any subformula thereof in the LC medium is preferably between 1 and 10% by weight, very preferably between 1 and 6% by weight.

[0353] Particularly preferred compounds are of the following sub-formula:

[0354] [ka]

[0355] During the ceremony, "Alkyl" and "alkyl * " each independently represent a straight-chain alkyl group having 1 to 6 C atoms, in particular ethyl, propyl or pentyl.

[0356] The use of the following compounds is particularly advantageous:

[0357] [ka]

[0358] In another preferred embodiment of the present invention the LC medium comprises one or more compounds of formula Y selected from the group consisting of the following subformulae:

[0359] [ka]

[0360] During the ceremony, R 5 is R 1 has one of the meanings given by the formula Y above, "Alkyl" denotes a linear alkyl group having 1 to 6 carbon atoms; L X represents H or F, X represents F, Cl, OCF3, OCHF2 or OCH=CF2; d represents 0 or 1; z and m each independently represent an integer of 1 to 6;

[0361] R in these compounds 5 is particularly preferably C 2~6 -alkyl or -alkoxy or C 2~6 -alkenyl, and d is preferably 1. X in these compounds is particularly preferably F. The LC media according to the invention preferably comprise one or more compounds of the abovementioned formulae in an amount of 5% by weight or more.

[0362] In compounds of formula B and its subformulas, R 1 and R 3 preferably denotes straight-chain alkyl or alkoxy having 1 to 6 C atoms, in particular methoxy, ethoxy, propoxy or butoxy, furthermore alkenyl having 2 to 6 C atoms, in particular vinyl, 1E-propenyl, 1E-butenyl, 3-butenyl, 1E-pentenyl, 3E-pentenyl or 4-pentenyl.

[0363] In a preferred embodiment of the invention the LC medium comprises one or more compounds of formula Y which are selected from the following sub-formulae:

[0364] [ka]

[0365] In the formula, R 1 , R 2 , L 1 , L 2 , X, x and Z x has the meaning given in formula Y, with the proviso that at least one of the rings X is cyclohexenylene.

[0366] Preferably, the group L 1 and L 2 and both represent F. More preferably, the group L 1 and L 2 One of them represents F and the other represents Cl.

[0367] The compound of formula LY is preferably selected from the group consisting of the following subformulae:

[0368] [ka]

[0369] In the formula, R 1 has the meaning shown above in formula Y, (O) represents an oxygen atom or a single bond, and v represents an integer of 1 to 6. 1 is preferably a linear alkyl having 1 to 6 C atoms or a linear alkenyl having 2 to 6 C atoms, in particular CH3, C2H5, n-C3H7, n-C4H9, n-C5H 11 , 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-.

[0370] Compounds of formula LY4 are highly preferred.

[0371] Preferably the LC medium comprises one, two or three compounds of the formula LY, very preferably of the formula LY4.

[0372] The proportion of compounds of the formula LY or any of its subformulas in the LC medium is preferably 1-10% by weight.

[0373] The LC medium comprises one or more compounds of formula Y selected from the following sub-formulae:

[0374] [ka]

[0375] In the formula, R 1 , R 2 , L 1 , L 2 , Y, y and Z y has the meaning given in formula Y, with the proviso that at least one of the rings Y is tetrahydropyran.

[0376] The compound of formula AY is preferably selected from the group consisting of the following subformulae:

[0377] [ka]

[0378] [ka]

[0379] During the ceremony, R 1 has the meaning given above, "Alkyl" denotes a linear alkyl group having 1 to 6 carbon atoms; (O) represents an oxygen atom or a single bond; v represents an integer of 1 to 6.

[0380] R 1 is preferably a linear alkyl having 1 to 6 C atoms or a linear alkenyl having 2 to 6 C atoms, in particular CH3, C2H5, n-C3H7, n-C4H9, n-C5H 11 , 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-.

[0381] In a preferred embodiment of the invention the LC medium comprises one or more compounds of formula B which are selected from the following sub-formulae:

[0382] [ka]

[0383] In the formula, L 1 , L 2 , R 1 and R 3 has the meaning given in formula B.

[0384] Preferred compounds of formula B1 are selected from the following sub-formulae:

[0385] [ka]

[0386] In the formula, R 1 and R 3 independently represent a linear alkyl group having 1 to 6 C atoms, in which one or more CH groups are connected to each other in such a way that O atoms are not directly linked to each other, such as -C≡C-, -CF2O-, -OCF2-, -CH=CH-, [ka] Each of the groups may be independently replaced by -O-, -CO-O-, or -O-CO-, and in which one or more H atoms may be replaced by a halogen atom. 1 and R 3 Highly preferred are compounds of formulae B1-1 and B1-2 in which "a" independently represents an alkyl group that is methyl, ethyl, propyl, butyl, pentyl, or hexyl, the alkyl groups preferably being linear. Highly preferred is when one "alkyl" is ethyl and the other "alkyl" is n-pentyl.

[0387] Compounds of formula B1-2 are highly preferred.

[0388] Preferably, the compound of formula B1-1 is selected from the group of compounds of formulae B1-1-1 to B1-1-11, preferably of formula B1-1-6.

[0389] [ka]

[0390] [ka]

[0391] During the ceremony, "Alkyl" and "alkyl * " each independently represent a linear alkyl group having 1 to 6 carbon atoms, "alkenyl" and "alkenyl * " each independently represent a linear alkenyl group having 2 to 6 carbon atoms, "alkoxy" and "alkoxy * " each independently represent a straight-chain alkoxy group having 1 to 6 C atoms.

[0392] Preferably, the compound of formula B1-2 is selected from the group of compounds of formulae B1-2-1 to B1-2-10, preferably of formula B1-2-6.

[0393] [ka]

[0394] [ka]

[0395] During the ceremony, "Alkyl" and "alkyl * " each independently represent a linear alkyl group having 1 to 6 carbon atoms, "alkenyl" and "alkenyl * " each independently represent a linear alkenyl group having 2 to 6 carbon atoms, "alkoxy" and "alkoxy * " each independently represent a straight-chain alkoxy group having 1 to 6 C atoms.

[0396] The LC medium may comprise one or more compounds of formula B1-1A and / or B1-2A.

[0397] [ka]

[0398] During the ceremony, (O) represents O or a single bond; R IIIA is an alkyl or alkenyl group having up to 7 C atoms or a group Cy-C m H 2m+1 - 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 alkyl or alkenyl, each having up to 3 C atoms, or an alicyclic group having 3, 4 or 5 ring atoms, which may be substituted by halogen or CN, and preferably represents cyclopropyl, cyclobutyl or cyclopentyl.

[0399] The compounds of formula B1-1A and / or B1-2A are contained in the medium alternatively or additionally, preferably additionally, to the compounds of formula B1-1 and B1-2.

[0400] Highly preferred compounds of formula B1-1A and / or B1-2A are:

[0401] [ka]

[0402] 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 C2H4F.

[0403] The proportion of compounds of formula B1 or any of its subformulas in the medium is preferably between 1 and 20% by weight, very preferably between 1 and 15% by weight.

[0404] Preferably the LC medium comprises one, two or three compounds of the formula B1 or any sub-formula thereof.

[0405] In a preferred embodiment of the invention the LC medium may comprise one or more compounds of formula B2-2

[0406] [ka]

[0407] During the ceremony R 1 , R 3 are the same or different and represent H, an alkyl or alkoxy group having 1 to 6 C atoms, provided that one or more CH groups in these groups are not directly linked to O atoms, and are -C≡C-, -CF2O-, -OCF2-, -CH=CH-, [ka] Each may be replaced independently by -O-, -CO-O- or -O-CO-, in which additionally one or more H atoms may be replaced by halogen.

[0408] The compound of formula B2-2 is preferably selected from the group of compounds of formulae B2-2-1 to B2-2-10.

[0409] [ka]

[0410] [ka]

[0411] In the formula, R 3 is alkyl having 1 to 6 C atoms, preferably ethyl, n-propyl or n-butyl, or alternatively cyclopropylmethyl, cyclobutylmethyl or cyclopentylmethyl, or alternatively -(CH2) n F (where n is 2, 3, 4 or 5), preferably C2H4F.

[0412] Particularly preferred compounds of formula B2 are selected from the following sub-formulae:

[0413] [ka]

[0414] The proportion of compounds of the formula B2 or any subformula thereof in the LC medium is preferably between 1 and 20% by weight, very preferably between 1 and 15% by weight.

[0415] Preferably the LC medium comprises one, two or three compounds of the formula B2 or sub-formulas thereof.

[0416] Preferred compounds of formula B3 are selected from the following sub-formulae:

[0417] [ka]

[0418] In the formula, R 1 has one of the meanings given in formula B3 and preferably denotes straight-chain alkyl having 1 to 6 C atoms, very preferably methyl, ethyl, propyl, butyl, pentyl or hexyl, more preferably ethyl or propyl, most preferably propyl, and X 1 has one of the meanings given in formula B3 and preferably denotes CF3 or OCF3.

[0419] Preferred compounds of formula B3 are selected from the following sub-formulae:

[0420] [ka]

[0421] In the formula, R 1has one of the meanings given in formula B3 and preferably denotes straight-chain alkyl having 1 to 6 C atoms, very preferably methyl, ethyl, propyl, butyl, pentyl or hexyl, more preferably ethyl or propyl, most preferably propyl.

[0422] Compounds of formula B3-1-1 and B3-2-2 are most preferred.

[0423] In another preferred embodiment the LC medium comprises one or more compounds of formula B or of sub-formulae B1, B2, B3, B1-1, B1-2, B2-1, B2-2, B2-3, B3-1, B3-2, B3-1-1, B3-1-2, B3-2-1 and B3-2-2, in which the dibenzofuran or dibenzothiophene group is a methyl or methoxy group, preferably a methyl group, more preferably in the para position relative to the substituent F, very preferably in the para position relative to the substituent F (i.e. in the presence of the terminal group R 2 or X 1 is substituted (at the meta position relative to

[0424] The proportion of compounds of the formula B3 or any subformula thereof in the LC medium is preferably between 1 and 20% by weight, very preferably between 1 and 10% by weight.

[0425] Preferably the LC medium comprises one, two or three compounds of the formula B3 or sub-formulas thereof.

[0426] Preferably, the total proportion of compounds of the formulae Y and B or their subformulae in the LC medium is between 2 and 25% by weight, very preferably between 3 and 20% by weight.

[0427] <Compound of formula ST> In some preferred embodiments of the present invention, the LC medium may further comprise one or more compounds of the general formula ST.

[0428] [ka]

[0429] In the formula, the individual substituents have the following meanings:

[0430] [ka]

[0431] X 21 , X 22 are each independently -O-, -CH2-, or -CHR 23 -or-NR 23 - represents R 21 and R 22 each independently represents an H atom, or an alkyl or alkoxy group having 1 to 12 C atoms, an alkenyl, alkynyl, alkenyloxy or alkoxyalkyl group having 2 to 12 C atoms, or a cycloalkyl group having 3 to 12 C atoms, provided that one or more non-adjacent CH groups in these groups are not directly linked to O atoms, and are -C≡C-, -CF2O-, -OCF2-, -CH=CH-, [ka] a cycloalkyl or cycloalkoxy group having 3 to 12 C atoms, which may be replaced by -O-, -CO-O- or -O-CO-, in which one or more H atoms may be replaced by halogen or a cycloalkyl or cycloalkoxy group having 3 to 12 C atoms in which one or more H atoms are replaced by halogen atoms; R 23 represents an H atom, an alkyl group or an alkoxy group having 1 to 10 C atoms, r represents 0 or 1.

[0432] LC media comprising compounds of the following sub-formulae ST-1, ST-2 and ST-3 showed particularly high long-term thermal and UV stability. [ka]

[0433] In the formula, the individual substituents have the following meanings:

[0434] [ka]

[0435] R 21 and R 22 each independently represents a hydrogen atom or an alkyl or alkoxy group having 1 to 7 carbon atoms, r represents 0 or 1.

[0436] In particularly preferred embodiments, the compound of general formula ST can be selected from the following specific structures:

[0437] [ka]

[0438] [ka]

[0439] [ka]

[0440] [ka]

[0441] In a further preferred embodiment, the LC media according to the invention may additionally comprise at least one sterically hindered phenol as set out in Table B below.

[0442] <Compound of Formula H> In some preferred embodiments of the present invention, the LC medium may further comprise at least one compound of formula H:

[0443] [ka]

[0444] During the ceremony, R 11 each independently represent an H atom, F, or an alkyl group having 1 to 20 C atoms, provided that one -CH2- group or, if present, multiple -CH2- groups may be replaced by -O- or -(C=O)-, but two adjacent -CH2- groups cannot be replaced by -O-, and one or, if present, multiple -CH2- groups may be replaced by -CH=CH- or -C≡C-, provided that one H atom or multiple H atoms may be replaced by F, OR 13 , N(R 13 )(R 14 ) or R 15 may be replaced by R 12 are each independently an H atom, an alkyl group having 1 to 20 C atoms (provided that one -CH2- group or multiple -CH2- groups may be replaced by -O- or -(C=O)-, but two adjacent -CH2- groups cannot be replaced by -O-), a hydrocarbon group containing a cycloalkyl or alkylcycloalkyl unit (provided that one -CH2- group or multiple -CH2- groups may be replaced by -O- or -(C=O)-, but two adjacent -CH2- groups cannot be replaced by -O-, but one H atom or multiple H atoms can be replaced by F, OR 13 , N(R 13 )(R 14 ) or R 15 ) or an aromatic or heteroaromatic hydrocarbon group (wherein one H atom or multiple H atoms may be replaced by OR 13 , N(R 13 )(R 14 ) or R 15 ) may be replaced by R 13 and R 14each independently represents an alkyl or acyl group having 1 to 10 carbon atoms or an aromatic hydrocarbon or carboxylic acid group having 6 to 12 carbon atoms, R 15 each independently represent an alkyl group having 1 to 10 C atoms, provided that one -CH2- group or multiple -CH2- groups may be replaced by -O- or -(C=O)-, but two adjacent -CH2- groups cannot be replaced by -O-, R 16 are each independently an H atom, an alkyl or alkoxy group having 1 to 10 C atoms, an O-cycloalkyl group having 3 to 12 C atoms, O · or OH, S 11 and S 12 are each independently an alkylene group having 1 to 20 C atoms (provided that one -CH2- group or, if present, multiple -CH2- groups may be replaced by -O- or -(C=O)-, but two adjacent -CH2- groups cannot be replaced by -O-, provided that one H atom or multiple H atoms are not selected from the group consisting of F, OR 13 , N(R 13 )(R 14 ) or R 15 ) or a single bond, Y 11 ~Y 14 each independently represents methyl or ethyl, X 11 represents C, Z 11 ~Z 14 are each independently -O-, -(C=O)-, -O-(C=O)-, -(C=O)-O-, -O-(C=O)-O-, -(NR 13 )-, -NR 13 -(C=O)- or a single bond, S 11 If is a single bond, Z 11 and Z 12 Both of these do not represent -O- at the same time;S 12 If is a single bond, Z 13 and Z 14do not simultaneously represent -O-; when q represents 0, Z 12 and Z 13 Both of these do not represent -O- at the same time, p represents 1 or 2; q represents 0 or 1; o represents (3-p), n represents an integer of 1 to 10; m represents an integer from 0 to 8, n×p represents an integer of 1 to 10, preferably 3 to 8, and [ka] represents an organic moiety having (m+n) bonding sites.

[0445] In some preferred embodiments of the present invention, in compounds of formula H:

[0446] [ka] teeth, [ka] represents

[0447] [ka] teeth, [ka] represents

[0448] [ka] are -(CH2-)2, -(CH2-)3, -(CH2-)4, -(CH2-)5, -(CH2-)6, -(CH2-)7, and -(CH2-)8, i.e., ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, and octane-1,8-diyl. [ka] represents and / or

[0449] During the ceremony, -Z 12 -S 11 -Z 11 - can be used independently in each occurrence: -O-, -S 11 -O-, -OS 11 -O-, -(C=O)-OS 11 -O-, -O-(C=O)-S 11 -O-, -O-(C=O)-S 11 -(C=O)-O-, -OS 11 -(C=O)-O-, -(C=O)-OS 11 -C-, -(C=O)-OS 11 -O-(C=O)-, or -(NR 13 )-S 11 -O-, -NR 13 -(C=O)-S 11 -(C=O)-O- or a single bond, preferably -O-, -S 11 -O-, -OS 11 -O-, -(C=O)-OS 11 -O-, -O-(C=O)-S 11 -O- or -OS 11 represents -(C=O)-O-, and / or S 11 preferably denotes an alkylene group having 1 to 20 C atoms, and / or R 11 if present, represents alkyl, alkoxy or H, preferably H or alkyl, and / or R 12 represents H, methyl, ethyl, propyl, isopropyl or 3-heptyl or cyclohexyl.

[0450] In a preferred embodiment of the present application, in the compound of formula H, [ka] is expressed as follows: [ka] represents a group selected from the group

[0451] In a further preferred embodiment of the present application, in the compound of formula H, [ka] is expressed as follows: [ka] represents a group selected from the group

[0452] In a further preferred embodiment of the present application, in compounds of formula H, p preferably represents 1,

[0453] [ka] teeth, [ka] Preferably -OS 11 -O-, -S 11 -O- or -OS 11 -, particularly preferably -OS 11 -O- or -S 11 Represents -O-.

[0454] In a further preferred embodiment of the invention, in the compound of formula H, the group [ka] is expressed as follows: [ka] represents a group selected from the group

[0455] In a further preferred embodiment of the invention, where p is 2, which may be the same or different from those above, in the compound of formula H:

[0456] [ka] is expressed as follows: [ka] represents a group selected from the group

[0457] In a further preferred embodiment of the present invention, which may be the same or different from those described above, in the compound of formula H,

[0458] [ka] occur independently of each other, [ka] Preferably [ka] Represents.

[0459] Compounds of the following general formulae H-1-1, H-1-2 and H-1-3 have been shown to be particularly effective UV stabilizers in LC media, especially in terms of VHR stability.

[0460] [ka]

[0461] In the formula, ZG, R 16 and n is as defined above, n represents an integer from 1 to 8. These compounds are highly suitable as stabilizers in LC media, stabilizing the VHR of the LC medium upon UV exposure.

[0462] In a particularly preferred embodiment, the one or more compounds of formula H may be selected from the group consisting of compounds of formulae H-2-1 to H-2-6 below:

[0463] [ka]

[0464] [ka]

[0465] [ka]

[0466] During the ceremony, R 11 each independently represent an H atom, an alkyl group having 1 to 20 C atoms, provided that one -CH2- group or, if present, multiple -CH2- groups may be replaced by -O- or -(C=O)-, but two adjacent -CH2- groups cannot be replaced by -O-, and one or, if present, multiple -CH2- groups may be replaced by -CH=CH- or -C≡C-, provided that one H atom or multiple H atoms may be replaced by F, OR 13 , N(R 13 )(R 14 ) or R 15 may be replaced by R 16 is a H atom or O · represents n represents an integer from 0 to 12, and S 11 and S 12 are each independently an alkylene group having 1 to 20 C atoms (provided that one -CH2- group or, if present, multiple -CH2- groups may be replaced by -O- or -(C=O)-, but two adjacent -CH2- groups cannot be replaced by -O-, provided that one H atom or multiple H atoms are not selected from the group consisting of F, OR 13 , N(R 13 )(R 14 ) or R 15 ) or represents a single bond.

[0467] In a preferred embodiment of the invention, the LC medium according to the invention comprises one or more compounds of the formula H which are in each case selected from the group of compounds of the following formulae:

[0468] [ka]

[0469] [ka]

[0470] [ka]

[0471] [ka]

[0472] [ka]

[0473] [ka]

[0474] [ka]

[0475] [ka]

[0476] [ka]

[0477] Further preferred LC media are selected from the following preferred embodiments, including any combination thereof: The total content of compounds of formula I in the LC medium is preferably 1 to 35% by weight, preferably 5 to 30% by weight, particularly preferably 10 to 28% by weight, based on the weight of the LC medium.

[0478] It has been found to be surprisingly advantageous in the LC media according to the invention to select compounds of formula I so that they can be described by a single formula selected from I-1-1 to I-1-17 and I-2-1 to I-2-53. It is particularly preferred that all compounds of formula I are represented by one of the following formulae: I-3-1, I-3-2, I-3-3, I-3-4, I-3-5, I-3-6, I-3-7, I-3-8, I-3-9, I-3-10, I-3- 11, I-3-12, I-3-15, I-3-16, I-3-17, I-3-18, I-3-19, I-3-20, I-3-21, I-3-22.

[0479] In some embodiments, the LC media of the present invention may comprise at least one, preferably at least two compounds of any of the following formulae: I-3-9-2, I-3-9-3, I-3-9-4, I-3-9-5, I-3-9-6, I-3-9-7, I-3-9-8, I-3-9-9, I-3-22-4, I-3-6-3, I-3-7-3.

[0480] It has been shown that in the LC media according to the invention, the combination of at least two different compounds of formula I not only has improved solubility compared to a single compound of formula I, but also significantly improves stability against UV light and high temperatures, thereby synergistically enhancing the stabilizing effect of the compound of general formula H.

[0481] If two compounds of formula I are present in the LC medium of the present invention, their weight ratio, based on the total weight of the two compounds of formula I, is preferably 10:90 to 90:10, particularly preferably 20:80 to 80:20, even more preferably 30:70 to 70:30.

[0482] The preferred content of one or more compounds of formula H in the LC medium depends, inter alia, on the inherent chemical stability of the LC medium and the properties of the compounds of formula H. 16 O · The compounds of formula H, which represent: 16 The compounds of formula H, in which represents an H atom, are advantageously used in proportions ranging from 50 ppm to 2000 ppm, based on the weight of the LC medium.

[0483] Further preferred embodiments are as follows:

[0484] The LC medium comprises one or more compounds of formula I or any of its sub-formulae, compounds of formula T1 and / or T2 and one or more compounds selected from the group consisting of the formulae Z1, Z2, Z3, Z4, Z5, Y, B, LY, AY, II, III, IV, V, VI, VII, VIII, IX, X, XI, XII, XIII, XIV, XV, XVI, XVIIa, XVIIb, XVIIc, XVIII, XIX, XX, XXI, XII, XXIII, XXIV, XXV, XXVI, XXVII, XXVIII, XXIX, XXX, XXX1, XXX2, XXX3, XXXI, XXXII, XXXIII and XXXIV and sub-formulae thereof.

[0485] The LC medium comprises one or more compounds of formula I or any of its subformulae, compounds of formula T1 and / or T2 and one or more compounds selected from the group consisting of the formulae Z1, Z2, Z3, Z4, Z5, Y, B, II, III, IV, VI, IX, X, XIV, XVI, XVIIa, XVIIb, XVIIc, XX, XII, XXIII, XXIX, XXXI and XXXIV and their subformulae.

[0486] The LC medium comprises one or more compounds of formula II, preferably selected from the group consisting of formulae II-1, II-2 and II-3, very preferably from formulae II-1 and II-2. The individual concentration of each of these compounds is preferably 2-15% by weight. The total concentration of these compounds is preferably 5-25% by weight.

[0487] The LC medium comprises one or more compounds of formula III, preferably selected from the group consisting of formulae III-1, III-4, III-6, III-16, III-19 and III-20, very preferably from the group consisting of formulae III-1, III-6, III-16 and III-20. The individual concentration of each of these compounds is preferably 2 to 15% by weight. The total concentration of these compounds is preferably 5 to 30% by weight.

[0488] The LC medium comprises one or more compounds of formula IV, preferably of formula IVa or IVc, very preferably of formula IVa1 or IVc1, most preferably of formula IVc1. The individual concentration of each of these compounds is preferably 2 to 15% by weight. The total concentration of these compounds is preferably 5 to 20% by weight.

[0489] The LC medium comprises one or more compounds selected from the formula VI, preferably from the formula VIb. The individual concentration of each of these compounds is preferably 1 to 20% by weight. The total concentration of these compounds is preferably 5 to 20% by weight.

[0490] The LC medium comprises one or more compounds selected from the formula Z1, preferably from the formula Z1-1, the total concentration of these compounds being preferably 1 to 25% by weight.

[0491] The LC medium comprises one or more compounds of formula Z2, preferably selected from the formulae Z2-1 and Z2-2, the total concentration of which is preferably 2 to 35% by weight, very preferably 3 to 25% by weight.

[0492] The LC medium comprises 5 to 20% by weight of a compound of the formula Z3, preferably of the formula Z3-1.

[0493] The LC medium comprises 5 to 20% by weight of a compound of the formula Z4, preferably of the formula Z4-1.

[0494] The LC medium comprises 10 to 65% by weight, very preferably 20 to 60% by weight, of compounds of the formula Z5.

[0495] The LC medium comprises one or more compounds of the formula XII, preferably of the formula XIIa or XIIb, very preferably of the formula XIIa and most preferably of the formula XIIa1. The concentration of these compounds is preferably between 2 and 15% by weight.

[0496] The LC medium comprises 1 to 15% by weight of a compound of the formula XIIb.

[0497] The LC medium comprises one or more compounds of the formula XIV, preferably of the formula XIVd, very preferably of the formula XIVd1, the concentration of these compounds preferably being between 2 and 10% by weight.

[0498] The LC medium comprises one or more compounds of the formula XVIb, preferably of the formulae XVIb-1, XVIb-2 and / or XVIb-3, the concentration of which is preferably between 2 and 15% by weight.

[0499] The LC medium comprises one or more compounds of the formula XVIc, preferably of the formulae XVIc-1, XVIc-2 and / or XVIc-3, the concentration of which is preferably between 2 and 20% by weight.

[0500] The LC medium comprises one or more compounds of the formula XVIg, preferably of the formulae XVIg-1 and / or XVIg-2, the concentration of which is preferably between 5 and 25% by weight.

[0501] The LC medium comprises one or more compounds selected from the group consisting of the formulae XVIIa, XVIIb and XVIIc, very preferably of the formula XVIIa where L is H and of the formula XVIIb where L is F. The total concentration of these compounds is preferably 0.5 to 5% by weight.

[0502] The LC medium comprises one or more compounds of the formula XX, preferably of the formula XXa, the concentration of which is preferably between 2 and 10% by weight.

[0503] The LC medium comprises one or more compounds of the formula XXI, preferably of the formula XXIa, the concentration of which is preferably between 2 and 10% by weight.

[0504] The LC medium comprises one or more compounds of the formula XXIII, preferably of the formula XXIIIa, the concentration of which is preferably between 0.5 and 5% by weight.

[0505] The LC medium comprises one or more compounds of the formula XXIX, preferably of the formula XXIXa, the concentration of which is preferably between 2 and 10% by weight.

[0506] The LC medium comprises one or more compounds of the formula XXX, preferably of the formula XXXa, the concentration of which is preferably between 2 and 10% by weight.

[0507] The LC medium comprises one or more compounds of the formula XXXI, the concentration of which is preferably between 2 and 10% by weight.

[0508] The LC medium comprises one or more compounds of the formula XXXI, the concentration of which is preferably between 2 and 10% by weight.

[0509] ·LC The medium comprises one or more compounds of formula XXXIV, preferably of formula XXXIVa, the concentration of which is preferably between 1 and 5% by weight.

[0510] The LC medium comprises one or more compounds of the formula I, preferably I-2-6, compounds of the formula T1 and / or T2, one or more compounds selected from the group consisting of the formulae Z1, Z2 and Z3, Z4, Z5 or subformulas thereof, one or more compounds selected from the group consisting of the formula XIV or subformulas thereof, one or more compounds selected from the group consisting of the formulae II, III, IV, VI, XX, XXIII and XXIX or subformulas thereof, and one or more compounds selected from the group consisting of the formulae XII, XVI, XVIIa, XVIIb, XVIIc, XXXI and XXXIV or subformulas thereof.

[0511] The LC medium comprises one or more compounds of the formula I, preferably I-2-6, compounds of the formula T1 and / or T2, one or more compounds selected from the group consisting of the formulae Z1, Z2 and Z3, Z4, Z5 or subformulas thereof, one or more compounds selected from the group consisting of the formulae Z1-1, Z2-2, Z5 and XIVd or subformulas thereof, one or more compounds selected from the group consisting of the formulae II, III, IVc, VIb, XXa, XXIIIa and XXIXa or subformulas thereof, and one or more compounds selected from the group consisting of the formulae XIIb, XVIb, XVIc, XVIIa, XVIIb, XVIIc, XXXI and XXXIVa or subformulas thereof.

[0512] The LC medium comprises one or more, preferably two or more, compounds of the formula I, preferably of the formula I-2-6, compounds of the formula T1 and / or T2, one or more compounds selected from the group consisting of the formulae Z1, Z2, Z3, Z4 and Z5 or subformulas thereof, one or more compounds of the formula Y, preferably selected from the group consisting of Y1 and Y2, one or more compounds selected from the group consisting of the formula XIV or subformulas thereof, one or more compounds selected from the group consisting of the formulae II, III, IV, VI, XX, XXIII and XXIX or subformulas thereof, and one or more compounds selected from the group consisting of the formulae XII, XVI, XVIIa, XVIIb, XVIIc, XXXI and XXXIV or subformulas thereof.

[0513] The LC medium comprises one or more, preferably two or more, compounds of the formula I, preferably of the formula I-2-6, compounds of the formula T1 and / or T2, one or more compounds selected from the group consisting of the formulae Z1, Z2, Z3, Z4 and Z5 or subformulas thereof, one or more compounds of the formula B, preferably selected from the group consisting of B1, B2 and B3, one or more compounds selected from the group consisting of the formulae Z1-1, Z2-2, Z5 and XIVd or subformulas thereof, one or more compounds selected from the group consisting of the formulae II, III, IVc, VIb, XXa, XXIIIa and XXIXa or subformulas thereof, and one or more compounds selected from the group consisting of the formulae XIIb, XVIb, XVIc, XVIIa, XVIIb, XVIIc, XXXI and XXXIVa or subformulas thereof.

[0514] Besides the compounds of the formula I and T1 and / or T2, the LC medium comprises further compounds selected from the group of the compounds of the formulae Z1, Z2, Z3, Z4, Z5, Y, B, IV, XII, XIV, XVI, XVIIa, XVIIb, XVIIc, XXI, XXIII, XXIX, XXX, XXXI and XXIV or their sub-formulae.

[0515] Besides the compounds of the formula I and T1 and / or T2, the LC medium comprises further compounds selected from the group of the compounds of the formulae Z1, Z2, Z3, IV, XII, XIV, XVI, XVIIa, XVIIb, XVIIc, XXI, XXIII, XXIX, XXX, XXXI and XXXIV or their sub-formulae.

[0516] The proportion of compounds of formula I or any of its sub-formulas in the LC medium is between 1 and 30% by weight, very preferably between 2 and 25% by weight, most preferably between 2 and 20% by weight.

[0517] The proportion of compounds of the formulae Z1, Z2 and Z3 or their sub-formulae in the total LC medium is between 10 and 65%, very preferably between 20 and 60%.

[0518] The proportion of compounds of formula Y or any of its sub-formulas in the total LC medium is between 1 and 20%, very preferably between 2 and 15%.

[0519] The proportion of compounds of formula B or any of its sub-formulas in the total LC medium is between 1 and 20%, very preferably between 2 and 18%.

[0520] The proportion of compounds of the formulae II, III, IV-VIII, XVIII-XXIII and XXVII-XXX in the total LC medium is 30-60% by weight.

[0521] The proportion of compounds of formulae IX to XV in the total LC medium is 40 to 70% by weight.

[0522] The proportion of compounds of the formulae XIV, XVIIa-c and XXXI-XXXIV in the total LC medium is 0.5-15% by weight.

[0523] In this application, the terms "alkyl" or "alkyl * (Alkyl * )" includes straight-chain and branched alkyl groups having 1 to 6 carbon atoms, especially the straight-chain groups methyl, ethyl, propyl, butyl, pentyl and hexyl. Groups having 2 to 5 carbon atoms are generally preferred.

[0524] The term "alkenyl" or "alkenyl * (Alkenyl * )" includes straight-chain and branched alkenyl groups having 2 to 6 carbon atoms, especially straight-chain groups. Preferred alkenyl groups are C2-C7-IE-alkenyl, C4-C6-3E-alkenyl, especially C2-C6-IE-alkenyl. Examples of particularly preferred alkenyl groups are vinyl, 1E-propenyl, 1E-butenyl, 1E-pentenyl, 1E-hexenyl, 3-butenyl, 3E-pentenyl, 3E-hexenyl, 4-pentenyl, 4Z-hexenyl, 4E-hexenyl and 5-hexenyl. Groups having up to 5 carbon atoms, especially CH2=CH, CH3CH=CH, are generally preferred.

[0525] The term "fluoroalkyl" preferably includes straight-chain groups having a terminal fluorine, i.e., fluoromethyl, 2-fluoroethyl, 3-fluoropropyl, 4-fluorobutyl, 5-fluoropentyl, 6-fluorohexyl, and 7-fluoroheptyl, although other positions of the fluorine are not excluded.

[0526] The term "oxaalkyl" or "alkoxy" preferably refers to a group of formula C n H 2n+1 -O-(CH2) m wherein n and m each independently represent 1 to 6. m may also represent 0. Preferably, n=1 and m=1 to 6 or m=0 and n=1 to 3. Even more preferably, the alkoxy or oxaalkyl group may also contain one or more additional O atoms such that the oxygen atoms are not directly linked to one another.

[0527] R 0 and X 0 By appropriately selecting the meaning of , the address time, threshold voltage, steepness of the transmission characteristic line, etc. can be modified in a desired manner. For example, 1E-alkenyl groups, 3E-alkenyl groups, 2E-alkenyloxy groups, etc., generally result in shorter address times, improved nematic tendency, and a higher ratio between the elastic constants K3 (bend) and K1 (splay) compared to alkyl and alkoxy groups. 4-alkenyl groups, 3-alkenyl groups, etc., generally result in lower threshold voltages and lower values ​​of K3 / K1 compared to alkyl and alkoxy groups. The LC media according to the present invention are distinguished in particular by high values ​​of Δε and therefore have significantly faster response times than LC media from the prior art.

[0528] The optimum mixing ratio of the compounds of the above formula will depend substantially on the desired properties, the selection of the components of the above formula and the selection of any further components that may be present.

[0529] The appropriate mixing ratio within the ranges indicated above can be easily determined for each case.

[0530] The total amount of the compounds of above formula in the liquid crystal medium according to the present invention is not important.Therefore, LC medium can contain one or more additional components for the purpose of optimizing various properties.However, the higher the total concentration of the compounds of above formula, the greater the observed effect of the desired improvement of the properties of the medium.

[0531] In a particularly preferred embodiment the liquid crystal media according to the invention have 0 represents F, OCF3, OCHF2, OCH=CF2, OCF=CF2 or OCF2-CF2H. A favorable synergistic effect with compounds of formulae I, T1 and / or T2, II and III results in particularly advantageous properties. In particular, mixtures comprising compounds of formulae I, T1 and / or T2, II and III are distinguished by their low threshold voltages.

[0532] The individual compounds of the abovementioned formulae and their subformulae which can be used in the liquid-crystalline media according to the invention are either known or can be prepared analogously to known compounds.

[0533] The present invention also relates to a process for preparing a liquid-crystalline medium as described above and below by mixing one or more compounds of formula I with one or more compounds of formula Y1, Y2 or Y3, one or more compounds of formula B and one or more compounds selected from the group consisting of formulae II, III, IV, VI, XIV, XII, XVIIa, XVIIb, XVIIc, XX, XXIII, XXIX, XXXI and XXXIV.

[0534] In another preferred embodiment of the invention the liquid crystal medium additionally comprises one or more polymerisable compounds, which are preferably selected from the group consisting of:

[0535] [ka]

[0536] In the formula, the individual radicals, identical or different at each occurrence, each have the following meanings, independently of one another: R a and R b is 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 may each independently be -C(R 0 )=C(R 00 )-, -C≡C-, -N(R 00 )-, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O-, wherein the O and / or S atoms are optionally replaced such that they are not directly linked to each other, and in addition, one or more H atoms may be replaced by F, Cl, Br, I, CN, P, or P-Sp-, with the proviso that B 1 and / or B. 2 If contains saturated C atoms, R a and / or R b may also represent a group spiro-linked to this saturated C atom, However, 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 is preferably an aromatic, heteroaromatic, alicyclic or heterocyclic group having 4 to 25 ring atoms, which may also contain fused rings, and which is unsubstituted or mono- or polysubstituted by 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 represent 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, optionally substituted silyl, optionally substituted aryl having 6 to 20 C atoms, or linear or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 25 C atoms, with the proviso that in addition one or more H atoms may be replaced by F, Cl, P or P-Sp-, P and Sp have the meanings indicated above, Y 1 represents a halogen, R x represents P, P-Sp-, H, halogen, linear, branched or cyclic alkyl having 1 to 25 C atoms (with the proviso that, in addition, one or more non-adjacent CH groups may be replaced by -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O- in such a way that the O and / or S atoms are not directly linked to one another, and with the proviso that, in addition, one or more H atoms may be replaced by F, Cl, P or P-Sp-), an optionally substituted aryl or aryloxy group having 6 to 40 C atoms, or an optionally substituted heteroaryl or heteroaryloxy group having 2 to 40 C atoms.

[0537] Particularly preferred compounds of formula M are those in which B 1 and B 2 are each independently 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 in addition, one or more CH groups in these groups may be replaced by N), cyclohexane-1,4-diyl (provided that in addition, one or more non-adjacent CH 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, indan-2,5-diyl or octahydro-4,7-methanoindan-2,5-diyl, with the proviso that all of these groups are compounds which may be unsubstituted or mono- or polysubstituted by L as defined above.

[0538] Particularly preferred compounds of formula M are those in which B 1 and B 2 are each independently 1,4-phenylene, 1,3-phenylene, naphthalene-1,4-diyl, or naphthalene-2,6-diyl.

[0539] Highly preferred compounds of formula M are selected from the following formulae:

[0540] [ka]

[0541] [ka]

[0542] [ka]

[0543] [ka]

[0544] [ka]

[0545] [ka]

[0546] In the formula, the individual radicals, identical or different at each occurrence, each have the following meanings, independently of one another: P 1 , P 2 , P 3 is a polymerizable group, 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, any group P 1 -Sp 1 -, P 2 -Sp 2 - and P 3 -Sp 3 -At least one of them is R aa provided that the group P 1 -Sp 1 -, P 2 -Sp 2 - and P 3 -Sp 3 -One or more of R aa may represent, preferably -(CH2) p1 -, -(CH2) p1 -O-, -(CH2) p1-CO-O- or -(CH2) p1 -O-CO-O-, where p1 is an integer of 1 to 12; R aa is H, F, Cl, CN, or a straight-chain or branched alkyl having 1 to 25 C atoms (provided that in addition, one or more non-adjacent CH groups may each independently be -C(R) such that O and / or S atoms are not directly linked to each other); 0 )=C(R 00 )-, -C≡C-, -N(R 0 )-, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O-, provided that in addition, one or more H atoms may be replaced by F, Cl, CN or P 1 -Sp 1 -), particularly preferably linear or branched, optionally monofluorinated or polyfluorinated alkyl, alkoxy, alkenyl, alkynyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 12 C atoms, with the proviso 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 alkyl having 1 to 12 C atoms, R y and R z is H, F, CH3 or CF3, X 1 , X 2 , X 3 is -CO-O-, -O-CO- or a single bond, Z M1 -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 wherein n is 2, 3, or 4, L is F, Cl, CN, or a linear or branched, optionally monofluorinated or polyfluorinated alkyl, alkoxy, alkenyl, alkynyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 12 C atoms, L', 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.

[0547] Compounds of formulae M2 and M13 are particularly preferred.

[0548] More preferred are the trireactive compounds M15 to M31, in particular M17, M18, M19, M22, M23, M24, M25, M30 and M31.

[0549] In the compounds of formulae M1 to M31, the group [ka] In the formula, L, identically or differently, in each occurrence, has one of the meanings given above or below, preferably F, Cl, CN, NO, CH, C, H, C(CH), CH(CH), CH, CH(CH)C, H, OCH, OC, H, COCH, COC, H, COOCH, COOC, H, CF, OCF, OCHF, OC, F or P-Sp-, very preferably F, Cl, CN, CH, C, H, OCH, COCH, OCF or P-Sp-, more preferably F, Cl, CH, OCH, COCH or OCF, in particular F or CH.

[0550] Preferred compounds of formulae M1 to M31 are those in which P 1 , P 2 and P 3represents an acrylate, methacrylate, oxetane, or epoxy group, very preferably an acrylate or methacrylate group.

[0551] Further preferred compounds of formulae M1 to M31 are those in which Sp 1 , Sp 2 and Sp 3 is a single bond.

[0552] Further preferred compounds of formulae M1 to M31 are those in which Sp 1 , Sp 2 and Sp 3 One of the bonds is a single bond, and Sp 1 , Sp 2 and Sp 3 is a compound in which another one of the groups is different from a single bond.

[0553] Further preferred compounds of the formulae M1 to M31 are those in which the group Sp is different from a single bond 1 , Sp 2 and Sp 3 -(CH2) s1 A compound representing -X"- (wherein s1 is an integer of 1 to 6, preferably 2, 3, 4, or 5, and X" is a bond to a benzene ring and is -O-, -O-CO-, -CO-O, -O-CO-O-, or a single bond).

[0554] Particular preference is given to liquid-crystalline media which comprise one, two or three polymerizable compounds of the formula M, preferably selected from the formulae M1 to M31.

[0555] More preferably, the liquid crystal medium according to the invention comprises one or more polymerizable compounds selected from Table E below.

[0556] The proportion of polymerizable compounds preferably selected from the formula M and table E in the liquid-crystalline medium is preferably 0.01 to 5%, very preferably 0.05 to 1%, most preferably 0.1 to 0.5%.

[0557] It has been observed that the addition of one or more polymerizable compounds, such as those selected from Formula M and Table E, to a liquid crystal medium can result in advantageous properties such as fast response times. Such liquid crystal media are particularly suitable for use in PSA displays, exhibiting low image fixing, rapid and complete polymerization, rapid generation of a low pretilt angle that is stable after UV exposure, high reliability, high VHR values ​​after UV exposure, and high birefringence. By appropriately selecting the polymerizable compound, it is possible to increase the absorption of the liquid crystal medium at longer UV wavelengths, thereby enabling the use of such longer UV wavelengths for polymerization, which is advantageous for the display manufacturing process.

[0558] The polymerizable group P is a group suitable for polymerization reactions, such as, for example, free-radical or ionic chain polymerization, polyaddition or polycondensation, or polymer-analogous reactions, such as addition or condensation onto the main chain. Groups for chain polymerization, especially those containing a C=C double bond or a -C≡C- triple bond, and groups suitable for ring-opening polymerization, such as, for example, oxetane or epoxide groups, are particularly preferred.

[0559] The preferred group P is CH2=CW 1 -CO-O-, CH2=CW 1 -CO-, [ka] CH2=CW 2 -(O) k3 -, CW 1 =CH-CO-(O) k3 -, CW 1 =CH-CO-NH-, CH2=CW 1 -CO-NH-, CH3-CH=CH-O-, (CH2=CH)2CH-OCO-, (CH2=CH-CH2)2CH-OCO-, (CH2=CH)2CH-O-, (CH2=CH-CH2)2N-, (CH2=CH-CH2)2N-CO-, HO-CW 2 W 3 -, HS-CW 2 W 3 -, HW 2 N-, HO-CW 2 W 3-NH-, CH2=CW 1 -CO-NH-, CH2=CH-(COO) k1 -Phe-(O) k2 -, CH2=CH-(CO) k1 -Phe-(O) k2 -, Phe-CH=CH-, HOOC-, OCN- and W 4 W 5 W 6 Si—, wherein W 1 represents H, F, Cl, CN, CF3, phenyl or alkyl having 1 to 5 C atoms, in particular H, F, Cl or CH3, and W 2 and W 3 each independently of one another denotes H or alkyl having 1 to 5 C atoms, in particular H, methyl, ethyl or n-propyl, W 4 , W 5 and W 6 each independently represents Cl, oxaalkyl or oxacarbonylalkyl having 1 to 5 carbon atoms, W 7 and W 8 each independently represent H, Cl or alkyl having 1 to 5 C atoms; Phe represents 1,4-phenylene optionally substituted with one or more groups L as defined in the above formula M other than P-Sp-; k1, k2 and k3 each independently represent 0 or 1, k3 preferably represents 1, and k4 represents an integer from 1 to 10.

[0560] A highly preferred group P is CH2=CW 1 -CO-O-, CH2=CW 1 -CO-, [ka] CH2=CW 2 -O-, CH2=CW 2 -, CW 1 =CH-CO-(O) k3 -, CW 1 =CH-CO-NH-, CH2=CW 1-CO-NH-, (CH2=CH)2CH-OCO-, (CH2=CH-CH2)2CH-OCO-, (CH2=CH)2CH-O-, (CH2=CH-CH2)2N-, (CH2=CH-CH2)2N-CO-, CH2=CW 1 -CO-NH-, CH2=CH-(COO) k1 -Phe-(O) k2 -, CH2=CH-(CO) k1 -Phe-(O) k2 -, Phe-CH=CH- and W 4 W 5 W 6 Si—, wherein W 1 represents H, F, Cl, CN, CF3, phenyl or alkyl having 1 to 5 C atoms, in particular H, F, Cl or CH3, and W 2 and W 3 each independently of one another denotes H or alkyl having 1 to 5 C atoms, in particular H, methyl, ethyl or n-propyl, W 4 , W 5 and W 6 each independently represents Cl, oxaalkyl or oxacarbonylalkyl having 1 to 5 carbon atoms, W 7 and W 8 each independently represent H, Cl, or alkyl having 1 to 5 C atoms; Phe represents 1,4-phenylene; k1, k2, and k3 each independently represent 0 or 1; k3 preferably represents 1; and k4 represents an integer of 1 to 10.

[0561] Very particularly preferred groups P are 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-, [ka] is selected from the group consisting of:

[0562] More preferably, the polymerizable group P is selected from the group consisting of vinyloxy, acrylate, methacrylate, fluoroacrylate, chloroacrylate, oxetane and epoxide, most preferably from the group consisting of acrylate and methacrylate.

[0563] Sp, when different from a single bond, is preferably of the formula Sp"-X", so that each group P-Sp- corresponds to the formula P-Sp"-X"-, in which: Sp" represents alkylene having 1 to 20, preferably 1 to 12, C atoms, which may optionally be mono- or polysubstituted by F, Cl, Br, I or CN, provided that in addition, one or more non-adjacent CH 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- may be substituted such that the O and / or S atoms are not directly linked to one another, “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 represents -, -C≡C-, -CH=CH-CO-O-, -O-CO-CH=CH- or a single bond; R 0 and R 00each independently represent H or alkyl having 1 to 20 C atoms, Y 2 and Y 3 each independently represents H, F, Cl or CN.

[0564] X" is preferably -O-, -S-, -CO-, -COO-, -OCO-, -O-COO-, or -CO-NR 0 -, -NR 0 -CO-, -NR 0 -CO-NR 00 - or a single bond.

[0565] Exemplary spacer groups Sp and -Sp"-X"- include, for example, -(CH2) p1 -, -(CH2CH2O) q1 -CH2CH2-, -CH2CH2-S-CH2CH2-, -CH2CH2-NH-CH2CH2- or -(SiR 0 R 00 -O) p1 wherein p1 is an integer from 1 to 12, q1 is an integer from 1 to 3, and R 0 and R 00 has the meaning shown in the formula M above.

[0566] Particularly preferred groups Sp and -Sp"-X"- are -(CH2) p1 -, -(CH2) p1 -O-, -(CH2) p1 -O-CO-, -(CH2) p1 -CO-O-, -(CH2) p1 -O-CO-O-, in which p1 and q1 have the meanings given above.

[0567] Particularly preferred radicals Sp" are in each case linear ethylene, propylene, butylene, pentylene, hexylene, heptylene, octylene, nonylene, decylene, undecylene, dodecylene, octadecylene, ethyleneoxyethylene, methyleneoxybutylene, ethylenethioethylene, ethylene-N-methyliminoethylene, 1-methylalkylene, ethenylene, propenylene and butenylene.

[0568] For the production of PSA displays, the polymerizable compounds contained in the liquid crystal medium are polymerized or (if one compound contains more than one polymerizable group) crosslinked by in situ polymerization in the liquid crystal medium between the substrates of the LC display, optionally with application of a voltage to the electrodes.

[0569] The structure of the PSA display according to the present invention corresponds to the usual configuration of a PSA display as described in the prior art cited at the beginning. A configuration without protrusions is preferred, in particular one in which the electrode on the color filter side is unstructured and only the electrode on the TFT side has slots. A particularly suitable and preferred electrode structure for PS-VA displays is described, for example, in US Patent Application Publication No. 2006 / 0066793.

[0570] The combination of the compounds of the above-mentioned preferred embodiments with the above-mentioned polymerizable compounds in the liquid-crystalline media according to the invention always leads to high clearing points and high VHR values, as well as low threshold voltages, low rotational viscosities and very good low-temperature stability.

[0571] By using a liquid crystal medium containing a polymerizable compound, a particularly low pretilt angle can be rapidly established in a PSA display. In particular, the liquid crystal medium also shows a significantly reduced response time, especially the gray-scale response time, in a PSA display compared with media from the prior art.

[0572] Liquid crystal media having a nematic liquid crystal phase, preferably no chiral liquid crystal phase, are generally preferred.

[0573] The present invention also relates to the use of a liquid-crystalline medium according to the invention as described above and below for electro-optical purposes, in particular for use in shutter glasses, for 3D applications in TN, PS-TN, STN, TN-TFT, OCB, IPS, PS-IPS, FFS, HB-FFS, XB-FFS, PS-FFS, positive VA and positive PS-VA displays, and also to electro-optical displays, in particular comprising a liquid-crystalline medium according to the invention of the aforementioned type and as described above and below, in particular TN, PS-TN, STN, TN-TFT, OCB, IPS, PS-IPS, FFS, HB-FFS, XB-FFS, PS-FFS, positive VA (vertically aligned) or positive PS-VA displays.

[0574] The present invention also relates to an electro-optical display, such as an STN or MLC display, having two flat parallel outer plates which together with a frame form a cell, integrated non-linear elements for switching individual pixels on the outer plates, and a nematic liquid-crystalline medium having positive dielectric anisotropy and high resistivity arranged in the cell, wherein the nematic liquid-crystalline medium is a liquid-crystalline medium according to the invention as described above and below.

[0575] The liquid-crystalline media according to the invention allow a significant expansion of the range of available parameters: the achievable combination of clearing point, viscosity at low temperature, excellent low-temperature stability, heat and UV stability and high optical anisotropy is far superior to that of prior art materials.

[0576] In particular, the compounds of formula I in combination with compounds of formula Y and / or B and additionally with compounds selected from formulae II to XXXIV or their sub-formulae, exhibit a moderate positive dielectric anisotropy while maintaining a low rotational viscosity and a low value of the ratio γ1 / K1, and at the same time a low dielectric constant ε perpendicular to the longitudinal axis of the liquid crystal molecules. ⊥ This leads to liquid crystal media with increased luminance, which allows for liquid crystal displays, especially in FFS, HB-FFS, XB-FFS and IPS modes, with high brightness and transmittance and low response times.

[0577] The liquid-crystalline media according to the invention are suitable for mobile applications and TFT applications, such as, for example, mobile phones and PDAs. Furthermore, the liquid-crystalline media according to the invention are particularly suitable for use in FFS, HB-FFS, XB-FFS and IPS displays based on dielectrically positive liquid crystals.

[0578] The liquid crystal media according to the present invention retain a nematic phase down to -20°C, preferably down to -30°C, particularly preferably down to -40°C, and a clearing point of 75°C or higher, preferably 80°C or higher, while at the same time achieving a rotational viscosity γ1 of 110 mPa·s or lower, particularly preferably 100 mPa·s or lower, thereby enabling excellent MLC displays with fast response times. The rotational viscosity is determined at 20°C.

[0579] The liquid-crystalline media according to the invention preferably have a dielectric anisotropy Δε at 20° C. and 1 kHz of +1.5 or more, very preferably +2 to +6.

[0580] The birefringence Δn at 20° C. of the liquid-crystalline medium according to the invention is preferably 0.08 to 0.15, very preferably 0.1 to 0.14.

[0581] The rotational viscosity γ1 of the liquid-crystalline media according to the invention is preferably 80 mPs·sec or less, more preferably 70 mPs·sec or less, very preferably 60 mPs·sec or less.

[0582] The ratio γ1 / K1 of the liquid-crystalline media according to the invention (where γ1 is the rotational viscosity γ1 and K1 is the elastic constant in splay deformation) is preferably 4.6 mPs·sec / pN or less, very preferably 4.2 mPs·sec / pN or less, most preferably 4.0 mPs·sec / pN or less.

[0583] The nematic phase range of the liquid-crystalline media according to the invention preferably has a width of at least 90° C., more preferably at least 100° C., particularly preferably at least 110° C. This range preferably extends from at least −25° C. to +80° C.

[0584] It goes without saying that, through a suitable selection of the components of the liquid-crystalline media according to the invention, it is possible to achieve higher clearing points (e.g., above 100°C) at higher threshold voltages, or lower clearing points at lower threshold voltages, while retaining other advantageous properties. It is likewise possible to obtain liquid-crystalline media with higher Δε and thus lower thresholds, with only a correspondingly small increase in viscosity. MLC displays according to the invention preferably operate in the first transmission minimum of Gooch and Tarry [C.H. Gooch and H.A. Tarry, Electron. Lett. 10, pp. 2-4, 1974; C.H. Gooch and H.A. Tarry, Appl. Phys. 8, pp. 1575-1584, 1975], in which case a lower dielectric anisotropy is sufficient to obtain the same threshold voltage as comparable displays in the second minimum, in addition to particularly favorable electro-optical properties, such as high steepness of the characteristic lines and low angle dependence of the contrast (DE 30 22 818). For this reason, the use of the liquid-crystalline media according to the invention at the first minimum makes it possible to achieve significantly higher resistivity values ​​than when the liquid-crystalline media contain cyano compounds. Through appropriate selection of the individual components and their weight proportions, a person skilled in the art can use simple conventional methods to set the required birefringence for a pre-specified layer thickness of an MLC display.

[0585] By measuring the voltage holding ratio (HR) [S. Matsumoto et al., Liquid Crystals, Vol. 5, p. 1320 (1989); K. Niwa et al., Proc. SID Conference, San Francisco, June 1984, p. 304 (1984); G. Weber et al., Liquid Crystals, Vol. 5, p. 1381 (1989)], the following formula was obtained:

[0586] [ka] or cyanophenylcyclohexanes of the formula

[0587] [ka] It has been shown that the liquid-crystalline media according to the invention comprising compounds of the formulae ST-1, ST-2, RV, IA and IB exhibit a significantly smaller decrease in HR upon exposure to UV than similar mixtures which contain esters of the formulae ST-1, ST-2, RV, IA and IB instead of the compounds of the formulae I, ST-1, ST-2, RV, IA and IB.

[0588] The light and UV stability of the liquid-crystalline media according to the invention is very good, ie they show a significantly smaller decrease in HR on exposure to light, heat or UV.

[0589] The construction of the MLC display according to the invention from polarizers, electrode substrates and surface-treated electrodes corresponds to the conventional design of this type of display, and in this specification the term conventional design is used in a broad sense to include all derivatives and modifications of MLC displays, in particular matrix display elements based on polycrystalline silicon TFTs or MIMs.

[0590] However, the major difference between the display according to the invention and previous conventional displays based on twisted nematic cells lies in the choice of liquid crystal parameters of the liquid crystal layer.

[0591] The liquid crystal media that can be used according to the present invention can be prepared in a conventional manner, for example by mixing one or more compounds of claim 1 with one or more compounds of formulae II to XXXV or with further liquid crystal compounds and / or additives. Generally, the desired amount of the component used in the smaller amount is dissolved in the component that constitutes the main composition, advantageously at elevated temperature. It is also possible to mix solutions of the components in an organic solvent, for example, acetone, chloroform or methanol, and then, after thorough mixing, remove the solvent again, for example by distillation.

[0592] The LC medium may also contain further additives known to those skilled in the art and described in the literature, such as polymerization initiators, inhibitors, surface-active substances, light stabilizers, antioxidants, e.g., BHT, TEMPOL, microparticles, free-radical scavengers, nanoparticles, etc. For example, 0-15% of pleochroic dyes or chiral dopants or initiators such as Irgacure® 651 or Irgacure® 907 can be added. Suitable stabilizers and dopants are listed in Tables C and D below.

[0593] In a preferred embodiment of the present invention the LC medium comprises one or more further stabilizers, preferably selected from the group consisting of the following formulae:

[0594] [ka]

[0595] During the ceremony, n is an integer of 1 to 6, preferably 3.

[0596] Highly preferred stabilizers are selected from the group consisting of the following formulae:

[0597] [ka]

[0598] In a preferred embodiment the LC medium comprises one or more stabilizers selected from the group consisting of the formulae S1-1, S2-1.

[0599] In a preferred embodiment the LC medium comprises one or more stabilizers selected from Table D.

[0600] Preferably, the proportion of stabilizers such as those of formulae S1 to S3 in the LC medium is between 10 and 1000 ppm, very preferably between 30 and 1000 ppm. In a further preferred embodiment, the proportion of stabilizers of formulae S1 to S3 in the LC medium is between 100 and 10000 ppm, very preferably between 300 and 5000 ppm.

[0601] In another preferred embodiment the LC medium according to the invention comprises a self-aligning (SA) additive, preferably in a concentration of 0.1 to 2.5%. The LC medium according to this preferred embodiment is particularly suitable for use in polymer-stabilized SA-FFS, SA-HB-FFS or SA-XB-FFS displays.

[0602] In a preferred embodiment, an SA-FFS, SA-HB-FFS or SA-XB-FFS display according to the invention comprises a polyimide alignment layer.

[0603] The SA additives for use in this preferred embodiment are selected from compounds comprising a mesogenic group and a linear or branched alkyl side chain terminated with one or more polar anchor groups selected from hydroxy, carboxy, amino or thiol groups.

[0604] Further preferred SA additives comprise one or more polymerizable groups linked to a mesogenic group, optionally via a spacer group. These polymerizable SA additives can be polymerized in the LC medium under conditions similar to those applied to the RM in the PSA process.

[0605] Suitable SA additives for inducing homeotropic alignment, particularly for use in SA-VA mode displays, are disclosed, for example, in US Patent Application Publication Nos. 2013 / 0182202, 2014 / 0838581, 2015 / 0166890 and 2015 / 0252265.

[0606] In another preferred embodiment, the LC medium or polymer-stabilized SA-FFS, SA-HB-FFS or SA-XB-FFS display according to the invention comprises one or more self-aligning additives selected from Table F below.

[0607] Furthermore, the liquid-crystalline medium can contain, for example, 0 to 15% by weight of pleochroic dyes, nanoparticles, conductive salts, preferably ethyl dimethyldodecylammonium 4-hexoxybenzoate, tetrabutylammonium tetraphenylborate, or crown ether complex salts (e.g., Haller et al., Mol. Cryst. Liq. Cryst. 24, 249-258 (1973)), substances that improve the electrical conductivity, or substances that modify the dielectric anisotropy, viscosity, and / or alignment of the nematic phase. Substances of this type are described, for example, in German Patent Applications Nos. 22 09 127, 22 40 864, 23 21 632, 23 38 281, 24 50 088, 26 37 430, and 28 53 728.

[0608] In the present invention and the following examples, the structures of liquid crystal compounds are represented by acronyms, and are converted to chemical formulas according to the following Tables A to C. m H 2m+1 , C n H 2n+1 and C l H 2l+1 or C m H 2m-1 , C n H 2n-1 and C l H 2l-1 are linear alkyl or alkylene groups, each having n, m and l carbon atoms in each case. Preferably, n, m and l are each independently 1, 2, 3, 4, 5, 6 or 7. Table A shows the codes for the ring elements of the nucleus of the compounds, Table B lists the bridging units, and Table C lists the meaning of the symbols for the leftmost and rightmost groups of the molecule. The acronyms consist of the code for the ring element with an optional linking group, followed by the code for the first hyphen and the leftmost group, and the code for the second hyphen and the rightmost group. Table D shows exemplary structures of compounds with their respective abbreviations.

[0609] <Table A: Ring elements>

[0610] [Table 1]

[0611] [Table 2]

[0612] [Table 3]

[0613] <Table B: Crosslinking Units>

[0614] [Table 4]

[0615] <Table C: Terminal group>

[0616] [Table 5]

[0617] [Table 6]

[0618] In the table, n and m are each integers, and the three dots "..." are places for other abbreviations from this table.

[0619] The following abbreviations are used: (n, m, k and l are each independently an integer, preferably 1 to 12, preferably 1 to 6; k and l may be 0, preferably 0 to 4, more preferably 0 or 2, most preferably 2; n is preferably 1, 2, 3, 4 or 5; in the combination "-nO-", it is preferably 1, 2, 3 or 4, more preferably 2 or 4; m is preferably 1, 2, 3, 4 or 5; in the combination "-Om", it is preferably 1, 2, 3 or 4, more preferably 2 or 4. The combination "-lVm" is preferably "2V1".)

[0620] Preferred mixture components are shown in Tables D and E.

[0621]

[0622] [Table 7]

[0623] [Table 8]

[0624] [Table 9]

[0625] In the following formulae, n and m each independently represent 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12, in particular 2, 3, 5, and more particularly 0, 4, 6.

[0626] [Table 10]

[0627] [Table 11]

[0628] Table 12

[0629] Table 13

[0630] Table 14

[0631] Table 15

[0632] Table 16

[0633] Table 17

[0634] Table 18

[0635] Table 19

[0636] Table 20

[0637] Table 21

[0638] Liquid-crystalline media which comprise at least one, two, three or more compounds from Table E are particularly preferred.

[0639] Table F shows dopants which can generally be added to the liquid-crystalline media according to the invention. The liquid-crystalline media preferably contain 0 to 10% by weight, in particular 0.01 to 5% by weight, particularly preferably 0.01 to 3% by weight, of dopant.

[0640] [Table 22]

[0641] [Table 23]

[0642] For example, stabilizers which can be added to the liquid crystal medium according to the present invention in an amount of 0 to 10% by weight, preferably 100 ppm to 10,000 ppm, are listed below.

[0643] [Table 24]

[0644] [Table 25]

[0645] [Table 26]

[0646] [Table 27]

[0647] [Table 28]

[0648] [Table 29]

[0649] Table H shows exemplary reactive mesogenic compounds (RM) that can be used in the liquid crystal media according to the present invention.

[0650] [Table 30]

[0651] [Table 31]

[0652] [Table 32]

[0653] [Table 33]

[0654] [Table 34]

[0655] [Table 35]

[0656] [Table 36]

[0657] [Table 37]

[0658] Table 38

[0659] Table 39

[0660] Table 40

[0661] Table 41

[0662] Table 42

[0663] Table 43

[0664] Table 44

[0665] Table 45

[0666] Table 46

[0667] Table 47

[0668] [Table 48]

[0669] [Table 49]

[0670] [Table 50]

[0671] [Table 51]

[0672] [Table 52]

[0673] In a preferred embodiment, the liquid-crystalline medium according to the invention comprises one or more polymerizable compounds, preferably selected from the polymerizable compounds of the formulae RM-1 to RM-182. Among these, the 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-14 5, RM-146, RM-147, RM-149, RM-156~RM-163, RM-169, RM-170, RM-171~RM-183 are particularly preferred.

[0674] Table I shows self-alignment additives for homeotropic alignment which can be used in the LC medium for SA-FFS, SA-HB-FFS and SA-XB-FFS displays according to the invention, optionally together with the polymerizable compounds of formula I.

[0675] Table 53

[0676] Table 54

[0677] Table 55

[0678] Table 56

[0679] Table 57

[0680] Table 58

[0681] Table 59

[0682] Table 60

[0683] Table 61

[0684] Table 62

[0685] Table 63

[0686] [Table 64]

[0687] [Table 65]

[0688] In a preferred embodiment, the LC media, SA-VA and SA-FFS displays according to the invention comprise one or more SA additives selected from the formulae SA-1 to SA-48, preferably from the formulae SA-14 to SA-48, very preferably from the formulae SA-20 to SA-34 and SA-44, in combination with one or more RM.

[0689] The following examples are intended to illustrate the invention without limiting it.

[0690] Above and below, percentage data represent weight percent. All temperatures are given in degrees Celsius. mp represents melting point and cl.p. represents clearing point. Furthermore, C represents crystalline state, N represents nematic phase, S represents smectic phase, and I represents isotropic phase. Data between these symbols represent transition temperatures. Furthermore, the following symbols are used:

[0691] V0 Fredericks capacitance threshold voltage at 25°C [V] V 10 10% transmission voltage [V], n e extraordinary refractive index measured at 25°C and 589 nm, n0Normal refractive index measured at 25°C and 589nm, Δn is the optical anisotropy measured at 25°C and 589 nm; ε ⊥ the permittivity (or "dielectric constant") perpendicular to the long axis of the molecule at 25°C and 1 kHz, ε ∥the permittivity (or "dielectric constant") parallel to the long axis of the molecule at 25°C and 1 kHz, Δε dielectric anisotropy at 25 °C and 1 kHz; cl.p. or T(N,I) clearing point [°C], ν Flow viscosity measured at 25℃ [mm 2 ·s -1 ], γRotational viscosity measured at 125°C [mPa·s], Elastic constant for "splay" deformation at K125°C [pN], Elastic constant for "twist" deformation at K225℃ [pN], Elastic constant for "bend" deformation at K325℃ [pN], and LTS (low-temperature stability) Low-temperature stability of bulk phase [time] VHR (voltage holding ratio) Voltage holding ratio.

[0692] All physical properties are determined according to "Merck Liquid Crystals, Physical Properties of Liquid Crystals", November 1997, Merck KGaA, Germany, unless otherwise stated, and apply for a temperature of 25°C. [Example]

[0693] <Comparison basic mixture M1> The nematic LC medium is formulated as follows:

[0694] [Table 66]

[0695] The LC medium exhibits a nematic phase at -14°C, whereas at lower temperatures the formation of a smectic phase occurs.

[0696] <Comparative mixture example S1> The nematic LC media according to the invention are formulated as follows:

[0697] [Table 67]

[0698] [ka]

[0699] The addition of ST-1-3 significantly increased the VHR after UV exposure compared to unstabilized Mixture M1 without affecting the remaining physical properties of Mixture M1. 100 is significantly improved.

[0700] <Comparison basic mixture M2> The nematic LC medium is formulated as follows:

[0701] [Table 68]

[0702] The LC medium exhibits a nematic phase at -15°C, whereas at lower temperatures the formation of a smectic phase occurs.

[0703] <Comparative mixture example S2> The nematic LC media according to the invention are formulated as follows:

[0704] [Table 69]

[0705] The addition of ST-2-3 significantly increased the VHR after UV exposure compared to unstabilized Mixture M2 without affecting the remaining physical properties of Mixture M2. 100 is significantly improved.

[0706] [ka]

[0707] <Base Mixture M3 of the Present Invention> The nematic LC medium is formulated as follows:

[0708] [Table 70]

[0709] Although the LC medium contains a high content of CC-3-V and CC-3-V1, it maintains a nematic phase even at -23°C and exhibits excellent low-temperature stability (LTS) even at -20°C due to the presence of CPTP-3-2.

[0710] <Mixture Example S3 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0711] [Table 71]

[0712] The addition of H-3-1 significantly increased the VHR after UV exposure compared to unstabilized Mixture M3 without affecting the remaining physical properties of Mixture M3. 100 is significantly improved.

[0713] [ka]

[0714] <Base Mixture M4 of the Present Invention> The nematic LC medium is formulated as follows:

[0715] [Table 72]

[0716] Despite the high content of CC-3-V and CC-3-V1, the liquid crystal medium maintains a nematic phase even at −26°C and exhibits excellent low-temperature stability (LTS) even at −20°C due to the presence of CPTP-3-O1.

[0717] Therefore, the phase transition temperature (nematic to smectic phase) can be significantly reduced by adding compounds of formula T1, such as CPTP-3-2 and CPTP-3-O1. Furthermore, CPTP-3-2 has better compatibility with liquid crystal media than CPTP-3-O1 at low temperatures.

[0718] <Mixture Example S4 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0719] [Table 73]

[0720] The addition of H-3-3 significantly increased the VHR after UV exposure compared to unstabilized Mix M4 without affecting the remaining physical properties of Mix M4. 100 is significantly improved.

[0721] [ka]

[0722] <Base Mixture M5 of the Present Invention> The nematic LC medium is formulated as follows:

[0723] [Table 74]

[0724] [ka]

[0725] <Mixture Example S5 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0726] [Table 75]

[0727] The addition of H-3-5 significantly increased the VHR after UV exposure compared to unstabilized Mix M5 without affecting the remaining physical properties of Mix M5. 100 is significantly improved.

[0728] [ka]

[0729] <Base Mixture M6 of the Present Invention> The nematic LC medium is formulated as follows:

[0730] [Table 76]

[0731] [ka]

[0732] <Mixture Example S6 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0733] [Table 77]

[0734] The addition of ST-1-3 significantly increased the VHR after UV exposure compared to unstabilized Mix M6 without affecting the remaining physical properties of Mix M6. 100 is significantly improved.

[0735] <Base Mixture M7 of the Invention> The nematic LC medium is formulated as follows:

[0736] [Table 78]

[0737] [ka]

[0738] <Mixture Example S7 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0739] [Table 79]

[0740] The addition of BHT-1 significantly increased the VHR after UV exposure compared to unstabilized Mix M7 without affecting the remaining physical properties of Mix M7. 100 is significantly improved.

[0741] [ka]

[0742] <Base mixture M8 of the present invention> The nematic LC medium is formulated as follows:

[0743] [Table 80]

[0744] <Mixture Example S8 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0745] [Table 81]

[0746] The addition of BHT-6 significantly increased the VHR after UV exposure compared to unstabilized Mix M8 without affecting the remaining physical properties of Mix M8. 100 is significantly improved.

[0747] [ka]

[0748] <Base Mixture M9 of the Invention> The nematic LC medium is formulated as follows:

[0749] [Table 82]

[0750] <Mixture Example S9 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0751] [Table 83]

[0752] The addition of BHT-6 significantly increased the VHR after UV exposure compared to unstabilized Mix M9 without affecting the remaining physical properties of Mix M9. 100 is significantly improved.

[0753] [ka]

[0754] <Base mixture M10 of the present invention> The nematic LC medium is formulated as follows:

[0755] [Table 84]

[0756] [ka]

[0757] <Mixture Example S10 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0758] [Table 85]

[0759] The addition of ST-1-3 significantly increased the VHR after UV exposure compared to unstabilized Mixture M10 without affecting the remaining physical properties of Mixture M10. 100 is significantly improved.

[0760] <Base Mixture M11 of the Invention> The nematic LC medium is formulated as follows:

[0761] [Table 86]

[0762] <Mixture Example S11 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0763] [Table 87]

[0764] [ka]

[0765] The addition of ST-1-3 significantly increased the VHR after UV exposure compared to unstabilized Mixture M11 without affecting the remaining physical properties of Mixture M11. 100 is significantly improved.

[0766] <Base Mixture M12 of the Invention> The nematic LC medium is formulated as follows:

[0767] [Table 88]

[0768] <Mixture Example S12 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0769] [Table 89]

[0770] In combination with SU-1, the addition of ST-1-3 significantly increased the VHR after UV exposure compared to unstabilized Mixture M12 without affecting the remaining physical properties of Mixture M12. 100 is significantly improved.

[0771] <Base Mixture M13 of the Invention> The nematic LC medium is formulated as follows:

[0772] [Table 90]

[0773] <Mixture Example S13 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0774] [Table 91]

[0775] In combination with SU-1, the addition of ST-1-3 significantly increased the VHR after UV exposure compared to unstabilized Mixture M13 without affecting the remaining physical properties of Mixture M13. 100 is significantly improved.

[0776] <Base Mixture M14 of the Invention> The nematic LC medium is formulated as follows:

[0777] [Table 92]

[0778] <Mixture Example S14 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0779] [Table 93]

[0780] In combination with SU-1, the addition of ST-1-3 significantly increased the VHR after UV exposure compared to unstabilized Mixture M14 without affecting the remaining physical properties of Mixture M14. 100 is significantly improved.

[0781] <Base Mixture M15 of the Invention> The nematic LC medium is formulated as follows:

[0782] [Table 94]

[0783] <Mixture Example S15 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0784] [Table 95]

[0785] The addition of SU-1 significantly improved the VHR after UV exposure compared to unstabilized Mixture M15 without affecting the remaining physical properties of Mixture M15. 100 is significantly improved.

[0786] <Base mixture M16 of the present invention> The nematic LC medium is formulated as follows:

[0787] [Table 96]

[0788] <Base Mixture M17 of the Invention> The nematic LC medium is formulated as follows:

[0789] [Table 97]

[0790] <Mixture Example S17 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0791] [Table 98]

[0792] The addition of SU-1 significantly increased the VHR after UV exposure compared to unstabilized Mixture M17 without affecting the remaining physical properties of Mixture M17. 100 is significantly improved.

[0793] <Base mixture M18 of the present invention> The nematic LC medium is formulated as follows:

[0794] [Table 99]

[0795] <Mixture Example S18 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0796] [Table 100]

[0797] The addition of SU-1 significantly improved the VHR after UV exposure compared to unstabilized Mixture M18 without affecting the remaining physical properties of Mixture M18. 100 is significantly improved.

[0798] <Base Mixture M19 of the Invention> The nematic LC medium is formulated as follows:

[0799] [Table 101]

[0800] <Mixture Example S19 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0801] [Table 102]

[0802] The addition of SU-1 significantly increased the VHR after UV exposure compared to unstabilized Mixture M19 without affecting the remaining physical properties of Mixture M19. 100 is significantly improved.

[0803] <Base Mixture M20 of the Invention> The nematic LC medium is formulated as follows:

[0804] [Table 103]

[0805] <Mixture Example S20 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0806] [Table 104]

[0807] The addition of SU-1 significantly increased the VHR after UV exposure compared to unstabilized mixture M20 without affecting the remaining physical properties of mixture M20. 100 is significantly improved.

[0808] <Base Mixture M21 of the Invention> The nematic LC medium is formulated as follows:

[0809] [Table 105]

[0810] <Mixture Example S21 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0811] [Table 106]

[0812] The addition of SU-1 significantly increased the VHR after UV exposure compared to unstabilized Mixture M21 without affecting the remaining physical properties of Mixture M21. 100 is significantly improved.

[0813] <Base Mixture M22 of the Invention> The nematic LC medium is formulated as follows:

[0814] [Table 107]

[0815] <Mixture Example S22 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0816] [Table 108]

[0817] The addition of SU-1 significantly improved the VHR after UV exposure compared to unstabilized Mixture M22 without affecting the remaining physical properties of Mixture M22. 100 is significantly improved.

[0818] <Base Mixture M23 of the Invention> The nematic LC medium is formulated as follows:

[0819] [Table 109]

[0820] <Mixture Example S23 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0821] [Table 110]

[0822] The addition of SU-1 significantly improved the VHR after UV exposure compared to unstabilized Mixture M23 without affecting the remaining physical properties of Mixture M23. 100 is significantly improved.

[0823] <Base Mixture M24 of the Invention> The nematic LC medium is formulated as follows:

[0824] [Table 111]

[0825] <Mixture Example S24 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0826] [Table 112]

[0827] The addition of SU-1 significantly improved the VHR after UV exposure compared to unstabilized Mixture M24 without affecting the remaining physical properties of Mixture M24. 100 is significantly improved.

[0828] <Base Mixture M25 of the Invention> The nematic LC medium is formulated as follows:

[0829] [Table 113]

[0830] <Mixture Example S25 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0831] [Table 114]

[0832] In combination with SU-1, the addition of ST-1-3 significantly increased the VHR after UV exposure compared to unstabilized Mixture M25 without affecting the remaining physical properties of Mixture M25. 100 is significantly improved.

[0833] <Base Mixture M26 of the Invention> The nematic LC medium is formulated as follows:

[0834] [Table 115]

[0835] <Base Mixture M27 of the Invention> The nematic LC medium is formulated as follows:

[0836] [Table 116]

[0837] <Mixture Example S27 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0838] [Table 117]

[0839] The addition of SU-1 significantly improved the VHR after UV exposure compared to unstabilized Mixture M27 without affecting the remaining physical properties of Mixture M27. 100 is significantly improved.

[0840] <Base Mixture M28 of the Invention> The nematic LC medium is formulated as follows:

[0841] [Table 118]

[0842] <Mixture Example S28 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0843] [Table 119]

[0844] The addition of SU-1 significantly improved the VHR after UV exposure compared to unstabilized Mixture M28 without affecting the remaining physical properties of Mixture M28. 100 is significantly improved.

[0845] <Base Mixture M29 of the Invention> The nematic LC medium is formulated as follows:

[0846] [Table 120]

[0847] <Mixture Example S29 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0848] [Table 121]

[0849] The addition of SU-1 significantly increased the VHR after UV exposure compared to unstabilized Mixture M29 without affecting the remaining physical properties of Mixture M29. 100 is significantly improved.

[0850] <Base Mixture M30 of the Invention> The nematic LC medium is formulated as follows:

[0851] [Table 122]

[0852] <Mixture Example S30 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0853] [Table 123]

[0854] The addition of SU-1 significantly improved the VHR after UV exposure compared to unstabilized Mixture M30 without affecting the remaining physical properties of Mixture M30. 100 is significantly improved.

[0855] <Base Mixture M31 of the Invention> The nematic LC medium is formulated as follows:

[0856] [Table 124]

[0857] <Mixture Example S31 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0858] [Table 125]

[0859] The addition of SU-1 significantly increased the VHR after UV exposure compared to unstabilized Mixture M31 without affecting the remaining physical properties of Mixture M31. 100 is significantly improved.

[0860] <Base Mixture M32 of the Invention> The nematic LC medium is formulated as follows:

[0861] [Table 126]

[0862] <Mixture Example S32 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0863] [Table 127]

[0864] In combination with SU-1, the addition of ST-1-3 significantly increased the VHR after UV exposure compared to unstabilized Mixture M32 without affecting the remaining physical properties of Mixture M32. 100 is significantly improved.

[0865] <Base Mixture M33 of the Invention> The nematic LC medium is formulated as follows:

[0866] [Table 128]

[0867] <Mixture Example S33 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0868] [Table 129]

[0869] The addition of SU-1 significantly increased the VHR after UV exposure compared to unstabilized Mixture M33 without affecting the remaining physical properties of Mixture M33. 100 is significantly improved.

[0870] <Base Mixture M34 of the Invention> The nematic LC medium is formulated as follows:

[0871] [Table 130]

[0872] <Mixture Example S34 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0873] [Table 131]

[0874] The addition of SU-1 significantly improved the VHR after UV exposure compared to unstabilized Mixture M34 without affecting the remaining physical properties of Mixture M34. 100 is significantly improved.

[0875] <Base Mixture M35 of the Invention> The nematic LC medium is formulated as follows:

[0876] [Table 132]

[0877] <Mixture Example S35 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0878] [Table 133]

[0879] The addition of SU-1 significantly improved the VHR after UV exposure compared to unstabilized Mixture M35 without affecting the remaining physical properties of Mixture M35. 100 is significantly improved.

[0880] <Base Mixture M36 of the Invention> The nematic LC medium is formulated as follows:

[0881] [Table 134]

[0882] <Mixture Example S36 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0883] [Table 135]

[0884] The addition of SU-1 significantly increased the VHR after UV exposure compared to unstabilized Mixture M36 without affecting the remaining physical properties of Mixture M36. 100 is significantly improved.

[0885] <Base Mixture M37 of the Invention> The nematic LC medium is formulated as follows:

[0886] [Table 136]

[0887] <Mixture Example S37 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0888] [Table 137]

[0889] The addition of SU-1 significantly improved the VHR after UV exposure compared to unstabilized Mixture M37 without affecting the remaining physical properties of Mixture M37. 100 is significantly improved.

[0890] <Base Mixture M38 of the Invention> The nematic LC medium is formulated as follows:

[0891] [Table 138]

[0892] <Base Mixture M39 of the Invention> The nematic LC medium is formulated as follows:

[0893] [Table 139]

[0894] <Base Mixture M40 of the Present Invention> The nematic LC medium is formulated as follows:

[0895] [Table 140]

[0896] <Mixture Example S40 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0897] [Table 141]

[0898] The addition of SU-1 significantly increased the VHR after UV exposure compared to unstabilized Mixture M40 without affecting the remaining physical properties of Mixture M40. 100 is significantly improved.

[0899] <Base Mixture M41 of the Present Invention> The nematic LC medium is formulated as follows:

[0900] [Table 142]

[0901] <Mixture Example S41 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0902] [Table 143]

[0903] The addition of SU-1 significantly increased the VHR after UV exposure compared to unstabilized Mixture M41 without affecting the remaining physical properties of Mixture M41. 100 is significantly improved.

[0904] <Base Mixture M42 of the Invention> The nematic LC medium is formulated as follows:

[0905] [Table 144]

[0906] <Base Mixture M43 of the Invention> The nematic LC medium is formulated as follows:

[0907] [Table 145]

[0908] <Mixture Example S43 of the Present Invention> The nematic liquid crystal media according to the invention are formulated as follows:

[0909] [Table 146]

[0910] The addition of SU-1 significantly improved the VHR after UV exposure compared to unstabilized Mixture M43 without affecting the remaining physical properties of Mixture M43. 100 is significantly improved.

Claims

1. Liquid-crystalline medium, characterized in that it comprises one or more compounds of the formula I and one or more compounds selected from the formulae T1 and T2. 【Chemistry 1】 wherein the individual substituents have the following meanings: R １ and R ２ are each independently an H atom, an alkyl or alkoxy group having 1 to 12 C atoms, or an alkenyl or alkenyloxy group having 2 to 12 C atoms (in which one or more non-adjacent CH ２ The groups are formed by bonding O atoms together so that they are not directly bonded to each other, such as -C≡C-, -CF ２ O-, -OCF ２ -, -CH=CH-, 【Chemistry 2】 -O-, -CO-O- or -O-CO-, in which one or more H atoms may be replaced by halogen atoms; or a cycloalkyl or cycloalkoxy group having 3 to 12 C atoms, in which one or more H atoms may be replaced by halogen atoms; Y ０ represents a H atom, an alkyl group having 1 to 3 C atoms, or an alkenyl group having 2 to 3 C atoms (in which one or more non-adjacent CH ２ The groups are formed by bonding O atoms together so that they are not directly bonded to each other, such as -C≡C-, -CF ２ O-, -OCF ２ -, -CH=CH-, -O-, -CO-O- or -O-CO-; A ０ , A １ , A ２ are each independently phenylene-1,4-diyl (provided that in addition, one or two CH groups may be replaced by N, and one or more H atoms may be replaced by halogen, CN, CH ３ , CHF ２ , C.H. ２ F, CF ３ , OCH ３ , OCHF ２ or OCF ３ ), cyclohexane-1,4-diyl (provided that in addition, one or two non-adjacent CH ２ groups may be replaced independently of one another 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 １ and Z ２ are each independently -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 represents -, -CH=CH-, -CF=CH-, -CH=CF-, -CF=CF-, -C≡C- or a single bond; k and l each independently represent 0, 1, 2, or 3. 【Transformation 3】 (In the formula, 【Chemistry 4】 【Transformation 5】 R ３ and R 4 are each independently an alkyl or alkoxy group having 1 to 12 carbon atoms or an alkenyl group having 2 to 12 carbon atoms (in which one or more CH ２ The groups are formed by bonding O atoms together so that they are not directly bonded to each other, such as -C≡C-, -CF ２ O-, -OCF ２ -, -CH=CH-, 【Transformation 6】 and each of the groups may be substituted with —O—, —CO—O—, or —O—CO—, and one or more H atoms in the group may be replaced by a halogen atom. L １～６ each independently represents H or F; X ０ are F, Cl, CN, SF ５ , SCN, NCS, a halogenated alkyl group or a halogenated alkoxy group having 1 to 6 C atoms, or a halogenated alkenyl group or a halogenated alkenyloxy group having 2 to 6 C atoms, Y １～３ each independently represent H, a linear or branched alkyl or alkoxy group having 1 to 6 C atoms, or a cycloalkyl or cycloalkoxy group having 3 to 6 C atoms, m and n each independently represent 0 or 1.

2. 2. The medium according to claim 1, characterized in that the compound of formula I is selected from the group consisting of the following compounds: 【Transformation 7】 【Transformation 8】 (In the formula, R １ and R ２ is as defined in claim 1, Y ０ represents an H atom or a methyl group, preferably an H atom, L １ ~L ６ each, independently of one another, represents an H atom, F, Cl or an alkyl group having 1 to 4 C atoms.

3. 3. The medium according to claim 1, wherein the compound or compounds of formulae T1 and T2 are selected from the group consisting of compounds of the following formulae: 【Chemistry 9】 【Chemistry 10】 During the ceremony, R ３ and R 4 are each independently an alkyl or alkoxy group having 1 to 6 carbon atoms or an alkenyl group having 2 to 6 carbon atoms (in which one or more CH ２ The groups are formed by bonding O atoms together so that they are not directly bonded to each other, such as -C≡C-, -CF ２ O-, -OCF ２ -, -CH=CH-, 【Chemistry 11】 and each of the groups may be substituted with —O—, —CO—O—, or —O—CO—, and one or more H atoms in the group may be replaced by a halogen atom. L １ and L ２ each independently represents H or F; X ０ represents CN, SCN, NCS or a halogenated alkyl group having 1 to 6 C atoms, Y １ and Y ２ are each independently H, a linear or branched alkyl or alkoxy group having 1 to 6 C atoms, or a cycloalkyl or cycloalkoxy group having 3 to 6 C atoms, preferably H or CH ３ Represents.)

4. 4. Liquid-crystalline medium according to claim 1 , characterized in that it comprises one or more compounds selected from the following formulae, the medium preferably comprising a total of 45% by weight or more of compounds of the formulae Z-1 and Z-4: 【Chemistry 12】 【Chemistry 13】 (In the formula, "Alkyl" and "Alkyl ＊ " is C １～６ represents alkyl, "Alkenyl" and "alkenyl ＊ " are each independently C ２～６ represents alkenyl.)

5. 5. The liquid-crystalline medium according to claim 1, comprising one or more compounds selected from the group consisting of the following formulae: 【Chemistry 14】 wherein the individual radicals, independently of one another, have the following meanings at each occurrence, which may be the same or different: 【Chemistry 15】 R ０ is R in claim 1 １ is one of the meanings given to X ０ is F, Cl, a halogenated alkyl group, a halogenated alkenyl group, a halogenated alkoxy group or a halogenated alkenyloxy group having up to 6 C atoms, L １～６ is H or F, Y ０ is H or CH ３ It is.)

6. 6. Liquid-crystalline medium according to claim 5, wherein the one or more compounds of the formula II are selected from the following subformulae: 【Chemistry 16】 【Chemistry 17】 (In the formula, R ０ and X ０ has the meaning given in formula II.

7. 6. Liquid-crystalline medium according to claim 5, wherein the one or more compounds of the formula III are selected from the following subformulae: [Chemistry 18] 【Chemistry 19】 【Chemistry 20】 【Chemistry 21】 (In the formula, R ０ and X ０ has the meaning given in formula II.

8. 8. The liquid-crystalline medium according to claim 1, further comprising one or more compounds selected from the group consisting of the following formulae: 【Chemistry 22】 (In the formula, R ０ , X ０ , L １ , L ２ and Y ０ has the meaning given in claim 5, L ３ and L ４ are each independently L １ has one of the meanings given to Z ０ is -C ２ H ４ -, -(CH ２ ) ４ -, -CH=CH-, -CF=CF-, -C ２ F ４ --, --CH ２ CF ２ -, -CF ２ CH ２ -, -CH ２ O-, -OCH ２ -, -COO-, -CF ２ O- or -OCF ２ -, and in formulas V and VI also represents a single bond, r represents 0 or 1, and s represents 0 or 1.

9. 9. The liquid-crystalline medium according to claim 1, comprising one or more compounds selected from the group consisting of the following formulae: 【Chemistry 23】 (In the formula, R １ and X ０ are R of claim 6, respectively. ０ and X ０ )

10. 10. Liquid-crystalline medium according to claim 1, characterized in that it comprises one or more compounds of the formula XIV 【Chemistry 24】 (In the formula, R １ and R ２ each independently represent an n-alkyl, alkoxy, oxaalkyl, fluoroalkyl or alkenyl, each having up to 6 C atoms.

11. Liquid-crystalline medium according to any one of claims 1 to 10, characterized in that it comprises one or more compounds of the formula XVI 【Chemistry 25】 (In the formula, L １ , R １ and R ２ has the meaning indicated in claim 1.

12. 12. The liquid-crystalline medium according to claim 1, comprising one or more compounds selected from the group consisting of the following formulae: 【Chemistry 26】 (In the formula, L １ , R １ and R ２ has the meaning indicated in claim 1.

13. 13. Liquid-crystalline medium according to any one of claims 1 to 12, characterized in that it comprises a compound of the formula I, T1 and / or T2 and one or more compounds selected from the group consisting of the formulae Z1, Z2, Z3, Z4, Z5, II, III, IV, V, VI, VII, VIII, XXVII, XXVIII, XXIX, XXX, XIV, XVI, XXXI, XXXII and XXXIII.

14. 14. Process for preparing a liquid-crystalline medium according to any one of claims 1 to 13, characterized in that one or more compounds of formula I and one or more compounds of formula T1 and / or T2 are mixed with one or more mesogenic compounds and optionally one or more polymerizable compounds and / or one or more additives.

15. Use of a liquid-crystalline medium according to any one of claims 1 to 13 for electro-optical purposes.

16. Electro-optical liquid crystal display comprising a liquid crystal medium according to any one of claims 1 to 13.

17. 17. An electro-optical liquid crystal display according to claim 16, characterized in that it is a TN, PS-TN, STN, TN-TFT, OCB, IPS, PS-IPS, FFS, HB-FFS, XB-FFS, PS-HB-FFS, PS-XB-FFS, SA-HB-FFS, SA-XB-FFS, polymer stabilized SA-HB-FFS, polymer stabilized SA-XB-FFS, positive VA or positive PS-VA display.

18. 17. An electro-optical liquid crystal display according to claim 16, characterized in that it is a FFS, HB-FFS, XB-FFS, PS-HB-FFS, PS-XB-FFS, IPS or PS-IPS display.

Images