Liquid crystal media

Abstract

A liquid crystal medium is provided. The invention relates to liquid-crystalline (LC) media with positive dielectric anisotropy and to liquid-crystal displays (LCDs) containing these media, in particular displays addressed by active matrix, and in particular energy-efficient LC displays of the 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. The media have improved long-term stability against UV radiation and high temperatures.

Description

[Technical field]

[0001] The present invention relates to liquid-crystalline (LC) media with positive dielectric anisotropy, to liquid-crystal displays (LCDs) comprising these media, in particular to displays addressed by active matrix, in particular energy-efficient liquid-crystal displays of the 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. The media have an improved 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 for both direct view and projection displays. Electro-optical modes used are 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 these modes utilize an electric field that is generated substantially perpendicular to the substrates and the liquid crystal layer.

[0003] Besides these modes, there are also electro-optical modes that utilize an electric field substantially parallel to the substrate and the liquid crystal layer. For example, WO 91 / 10936 (Patent Document 1) discloses liquid crystal displays in which the electric signal is generated such that the electric field has a component parallel to the liquid crystal layer, and which have since become known as in-plane switching (IPS) displays. The principle of operation of such displays 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 with an interdigitated comb structure. 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 for example discloses various possibilities for the design of electrodes and for 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 comb-structured and the other unstructured. This generates strong so-called "fringe fields", i.e. a strong electric field close to 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 the contrast. FFS displays usually comprise an LC medium with positive dielectric anisotropy and an alignment layer, usually of polyimide, which provides a planar alignment to the molecules of the LC medium.

[0008] Liquid crystal displays of IPS and FFS electro-optical modes are 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.Although generally in FFS displays, dielectrically positive liquid crystal medium with a rather low value of dielectric anisotropy is used, in some cases, liquid crystal medium with a dielectric anisotropy of only about 3 or less is also used in IPS displays.

[0009] Further improvements have been achieved with the HB-FFS mode, which, in contrast to conventional FFS technology, allows a higher transmission and therefore 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, in particular for FFS and IPS displays, are known, for example, from JP 07-181439 A (Patent Document 5), EP 0 667 555 A (Patent Document 6), EP 0 673 986 A (Patent Document 7), DE 195 09 410 A (Patent Document 8), DE 195 28 106 A (Patent Document 9) and DE 195 28 107 A (Patent Document 10). However, these compositions have certain drawbacks. Among other defects, most of them result in disadvantageously long address times, have inappropriate values ​​of resistivity and / or require excessively high operating voltages. Herein, improvements are required in both operating properties and storage stability.

[0012] FFS and IPS displays can be operated as active-matrix displays (AMD) or as passive-matrix displays (PMD). In the case of active-matrix displays, the individual pixels are usually addressed by integrated non-linear active elements, e.g. thin-film transistors (TFTs), whereas in the case of passive-matrix displays, the individual pixels are usually 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 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 FK 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 LEDs and FRP medium therefore places special demands on the UV stability and temperature resistance of the FRP medium. State-of-the-art MFK displays therefore do not meet today's requirements.

[0018] Recently, MFK displays are increasingly used in outdoor applications, such as PIDs (Public Information Displays) for displaying various kinds of information in stations, roads, airports, hotels and shopping malls. Compared with traditional MFK displays, such as those used in television applications, PIDs must have much higher long-term resistance to solar UV radiation and high temperatures, as well as a wider operating temperature range. [Prior art documents] [Patent documents]

[0019] [Patent Document 1] WO 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 A1 [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, in particular for FFS and IPS displays, but also for TN, positive VA or STN displays, in particular for active matrix displays, such as those addressed by TFT, which does not exhibit the above-indicated disadvantages or exhibits them only to a lesser extent and preferably has high resistivity, low threshold voltage, high dielectric anisotropy, good low temperature stability (LTS), fast response times and low rotational viscosity, excellent long-term stability towards UV radiation and towards elevated operating temperatures and allows high brightness.

[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, but it has been found that prior art liquid crystal materials often do not achieve all these requirements simultaneously.

[0024] Surprisingly, the liquid crystal media according to the invention comprising a combination of two or more, preferably three or more, compounds of formula I and at least one compound of formula H show several improvements, in particular good solubility and γ1 / k when used in FFS mode displays. 11 It was found that this allows for a fast response time, as shown in the figure.

[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 which are 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 that contain thiophene-2,5-diyl units directly linked to 2- and / or 6-substituted-1,4-phenylene units. WO 2010 / 099853 describes the development of novel materials for use in LC displays. This object has been achieved by providing compounds of the general formula:

[0027] [ka]

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

[0029] Specific examples described are, for example, the following compounds (see International Publication No. WO 2010 / 099853 (Patent Document 11)).

[0030] [ka]

[0031] For many practical applications in liquid crystal displays, known liquid crystal media containing thiophene compounds are not sufficiently stable: exposure to, in particular, UV radiation, but even irradiation by conventional backlighting, results in a deterioration of, in particular, the electrical properties, so that, for example, the electrical conductivity increases significantly.

[0032] DE 10 2010 027 099 A1 describes LC media which contain compounds as disclosed in WO 2010 / 099853 A1 and bithienyl derivatives of the formula below as stabilizers:

[0033] [ka] These bithienyl derivatives are preferably employed in combination with thiophene-1,1-dioxide derivatives of the formula:

[0034] [ka]

[0035] In both of the above equations, A 1 and A 2 represents 1,4-phenylene or 1,4-cyclohexylene, and Z 1 and Z 2 represents a single bond. Specific examples mentioned are the following compounds (see DE 10 2010 027 099 A1):

[0036] [ka] [Means for solving the problem]

[0037] A subject of the invention is a liquid-crystalline medium, characterised in that it comprises two or more, preferably three or more, compounds of the formula I.

[0038] [ka]

[0039] in which the individual radicals have the following meanings: R 1 and R 2each independently represents 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 not directly linked to O atoms, and are -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; A 0 , A 1 , A 2 each independently of the other represents 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 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 represent, independently of one another, -CF2O-, -OCF2-, -CHO-, -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.

[0040] In addition to the two or more compounds of formula I as defined above, the medium comprises one or more compounds of formula H.

[0041] [ka]

[0042] During the ceremony, R 11 each independently represents an H atom, F, or an alkyl group having 1 to 20 C atoms, with the proviso 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-, with the proviso 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 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 are replaced by OR 13 , N(R 13 )(R 14) or R 15 ) may be replaced by R 13 and R 14 each independently represents an alkyl or acyl group having 1 to 10 C atoms or an aromatic hydrocarbon or carboxylic acid group having 6 to 12 C atoms, R 15 each independently represent an alkyl group having 1 to 10 C atoms, with the proviso that one -CH2- group or several -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 each independently represents 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 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 12Both of these do not represent -O- at the same time;S 12 If is a single bond, Z 13 and Z 14 do 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 from 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) binding sites.

[0043] The present invention further relates to the use of liquid-crystalline media 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 FFS, HB-FFS, IPS, PS-HB-FFS and PS-IPS displays.

[0044] The present invention further relates to electro-optical liquid crystal displays comprising a liquid crystal medium as described above and below, 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, preferably FFS, HB-FFS, IPS, PS-HB-FFS or PS-IPS displays. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0045] In this application, all atoms also include their isotopes. In a preferred embodiment, one or more hydrogen atoms (H) are replaced with deuterium (D), where high deuteration enables or simplifies analytical determination of the compound, especially at low concentrations.

[0046] In the above and below equations, R 0 , R 1 , R 11 , R 12 , R 13 and R 2 If 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 linear alkyl having 2 to 6 C atoms.

[0047] 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.

[0048] R 0 , R 1 , R 11 , R 12 or R 2 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 each other.

[0049] In another preferred embodiment, one or more R 0 , R 1 , R 11 , R 12 or R 2 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, S 2 is H, C 1~12 -Alkyl or C 2~12 -alkenyl; and very preferably one or more R 0 , R 1 and R 2 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.

[0050] R 0 , R 1 , R 11 , R 12 or R 2 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 especially denotes 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.

[0051] R 0 , R 1 , R 11 , R 12 or R 2 When is an alkyl or alkenyl group at least monosubstituted with a halogen, the group is preferably linear and the halogen is preferably F or Cl. 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.

[0052] In the above and below equations, X 0 is preferably F, Cl or a mono- or polyfluorinated alkyl or alkoxy group having 1, 2 or 3 C atoms or a mono- or polyfluorinated alkenyl group having 2 or 3 C atoms.0 is particularly preferably F, Cl, CF3, CHF2, OCF3, OCHF2, OCFHCF3, OCFHCHF2, OCFHCHF2, OCF2CH3, OCF2CHF2, OCF2CHF2, OCF2CF2CHF2, OCF2CF2CHF2, OCFHCF2CF3, OCFHCF2CHF2, OCF2CF2CF3, OCF2CF2CClF2, OCClFCF2CF3, OCH=CF2 or CH=CF2, very particularly preferably F or OCF3, furthermore CF3, OCF=CF2, OCHF2 or OCH=CF2.

[0053] The use of compounds of formula I together with compounds of the formulae Z1 to Z3 or subformulae thereof in the LC media according to the invention results in a ε ⊥ At the same time, the rotational viscosity and the ratio γ1 / k 22 and γ1 / k 11 This makes it possible to achieve a reduction in the response time.

[0054] Compound of Formula I A 0 Preference is given to LC media comprising compounds of formula I, in which A represents phenylene-1,4-diyl, in which 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, OCH3, OCHF2, CF3 or OCF3. 0 but [ka] and very particularly preferably A 0 but [ka] Particularly preferred are compounds which represent:

[0055] Preferred compounds of formula I result in media which have particularly high clearing points, low rotational viscosities, broad nematic phases, high birefringence and excellent thermal and UV stability.

[0056] Further preferred are compounds of formula I in which m and n are 0, 1 or 2, particularly preferably 0 or 1. Particularly preferred are compounds of formula I in which n is 0, i.e. the thiophene ring is a terminal ring. Further preferred are compounds of formula I in which m is 0, 1 or 2, preferably 1 or 2, very particularly preferably 1.

[0057] In formula I, 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.

[0058] Z in Formula I 1 and Z 2 Particularly preferably represents -CF2O-, -OCF2- or a single bond, with a single bond being particularly preferred.

[0059] A in Formula I 1 and A 2 is particularly preferably [ka] It preferably represents unsubstituted 1,4-phenylene, in which L represents halogen, CF3 or CN, preferably F.

[0060] More preferred are compounds of formula I below.

[0061] R 1 and R 2 each independently of one another denotes H, F, Cl, Br, -CN, -SCN, -NCS, SF5, halogen or alkyl, alkenyl or alkynyl having 1 to 8, preferably 1 to 5, C atoms, each of which may be substituted by halogen, in particular by F.

[0062] Particularly preferred groups R in formula I 1 and R 2stands for H, halogen or alkyl, alkenyl, alkynyl or alkoxy having 1 to 12, preferably 1 to 8, C atoms, each of which may be substituted by halogen, in particular by F, with H, F, alkyl, alkenyl or alkynyl having 1 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, R 2 is H or alkyl. R 1 , R 2 R each independently of one another very particularly preferably represents unbranched alkyl having 1 to 5 C atoms. 1 and R 2 If R1 represents a substituted alkyl, alkoxy, alkenyl or alkynyl, the total number of C atoms in the two groups R1 and R2 is preferably less than 10.

[0063] Preferred alkyl groups are for example methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl and n-octyl.

[0064] Preferred alkenyl groups are, for example, ethenyl, propenyl, butenyl and pentenyl.

[0065] Preferred alkynyl groups are, for example, ethynyl, propynyl, butynyl, pentynyl, hexynyl, heptynyl and octynyl.

[0066] Preferred alkoxy groups are for example methoxy, ethoxy, n-propoxy, n-butoxy, n-pentoxy, n-hexoxy, n-heptoxy, n-octoxy.

[0067] Halogen preferably denotes F or Cl.

[0068] Particularly preferred compounds of formula I are those selected from the following subformulae:

[0069] [ka]

[0070] [ka]

[0071] In the formula, R 1 and R 2 has the meaning given in general formula I, L 1 ~L 6 each independently represents H or F, where R 1 and R 2 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.

[0072] Particularly preferred is optionally fluorinated alkyl, alkenyl or alkynyl having 1 to 5 C atoms. 2 preferably represents F. In formulae I-1-4 to I-1-6, L 3 and L 4 preferably represents H. In formulae I-1-4 to I-1-6, L 3 and L 4 preferably represents F.

[0073] In particularly preferred embodiments, the compound of formula I is selected from the following structures:

[0074] [ka]

[0075] 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, an alkenyl, alkenyloxy, or alkoxyalkyl group having 1 to 7 C atoms, or a cycloalkyl or cycloalkoxy group having 3 to 12 C atoms, in which one or more CH2 groups are not directly bonded to O atoms, and are represented by -C≡C-, -CF2O-, -OCF2-, -CH=CH-, [ka] It may be substituted by -O-, -CO-O- or -O-CO-, in which one or more H atoms may be replaced by halogen atoms, and in which one or more H atoms may be replaced by halogen atoms.

[0076] LC media according to the invention which have particularly high long-term stability towards UV radiation and high temperatures and low rotational viscosity are obtained with the following compounds of the general formula I:

[0077] [ka]

[0078] [ka]

[0079] [ka]

[0080] [ka]

[0081] [ka]

[0082] [ka]

[0083] In the formula, R 1 and R 2 is as defined above.

[0084] In addition, particular preference is given to LC media which comprise a compound of formula I:

[0085] [ka]

[0086] [ka]

[0087] [ka]

[0088] The most preferred compounds of formula I especially include one or more of the following:

[0089] [ka]

[0090] As a further possibility, compounds of formula I below can be used:

[0091] [ka]

[0092] [ka]

[0093] Compounds of formula I can be prepared analogously to methods known to those skilled in the art and described, for example, in standard works of organic chemistry such as Houben-Weyl, Methoden der organischen Chemie [Methods of Organic Chemistry], Thieme-Verlag, Stuttgart.

[0094] <Compound of formula H> In some preferred embodiments of the present invention, in the compound of formula H,

[0095] [ka] teeth, [ka] represents

[0096] [ka] teeth, [ka] represents

[0097] [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

[0098] During the ceremony, -Z12 -S 11 -Z 11 -, in each occurrence, independently, -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=O)-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.

[0099] 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:

[0100] 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:

[0101] In a further preferred embodiment of the present application, in the compounds of formula H, p preferably represents 1,

[0102] [ka] teeth, [ka] Preferably -OS 11 -O-, -S 11 -O- or -OS 11 -, particularly preferably -OS 11 -O- or -S 11 Represents -O-.

[0103] 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:

[0104] In a further preferred embodiment of the invention, where p, which may be the same or different as above, is 2, in the compound of formula H:

[0105] [ka] is expressed as follows: [ka] represents a group selected from the group:

[0106] In a further preferred embodiment of the invention, which may be the same or different as above, in the compound of formula H,

[0107] [ka] are, independently of each other in each occurrence, [ka] Preferably [ka] Represents.

[0108] 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 liquid crystal mixtures, especially in terms of VHR stability.

[0109] [ka]

[0110] In the formula, ZG, R 16 and n is as defined above, n representing an integer from 1 to 8. These compounds are highly suitable as stabilizers in liquid crystal mixtures, stabilizing the VHR of the mixture upon UV exposure.

[0111] 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:

[0112] [ka]

[0113] [ka]

[0114] [ka]

[0115] During the ceremony, R 11 each independently represents an H atom, an alkyl group having 1 to 20 C atoms, with the proviso 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-, with the proviso 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 each independently represents 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 selected from the group consisting of F, OR 13 , N(R 13 )(R 14 ) or R 15 ) or represents a single bond.

[0116] In a preferred embodiment of the invention, the medium according to the invention comprises one or more compounds of the formula H, in each case selected from the group of compounds of the following formulae:

[0117] [ka]

[0118] [ka]

[0119] [ka]

[0120] [ka]

[0121] [ka]

[0122] [ka]

[0123] [ka]

[0124] [ka]

[0125] [ka]

[0126] [ka]

[0127] 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 compound of formula H, which represents 16 The compounds of formula H, in which represents an H atom, are advantageously used in a proportion ranging from 50 ppm to 2000 ppm, based on the weight of the LC medium.

[0128] <More mesogenic components> In addition to the compounds of formulae I and H, the medium preferably comprises one or more compounds selected from the following formulae:

[0129] [ka]

[0130] 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 -alkenyl. Compounds of formula Z1 and Z2 are highly preferred.

[0131] Preferred compounds of formulae Z1 to Z6 are those selected from the following sub-formulae:

[0132] [ka]

[0133] [ka]

[0134] 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.

[0135] Preferably, the total proportion of compounds of formulae Z1, Z2, Z3, Z4, Z5 and Z6 or their subformulae, such as 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, the compounds of formula Z1-1 are used in a concentration range of 10% by weight to 60% by weight, more preferably 10% by weight to 40% by weight, based on the total weight of the LC medium.

[0136] Preferably the medium comprises one, two or three compounds selected from formulae Z1, Z2, Z3 and Z4 or sub-formulae thereof.

[0137] The medium may additionally contain one or more compounds of the following general formula:

[0138] [ka]

[0139] During the ceremony, R” is C 1~6 -Alkyl, C 1~6 -Alkoxy or C 2~6 -alkenyl, "Alkenyl" is C 2~6 -Alkenyl.

[0140] The compound of formula XII is preferably selected from the following subformulae:

[0141] [ka]

[0142] In the formula, "alkyl" is methyl, butyl, pentyl, or hexyl.

[0143] Particularly preferred are compounds of formula XIIa. In formula IIXb, "alkyl" is preferably each independently n-C3H7, n-C4H9 or n-C5H 11 , in particular n-C3H7.

[0144] Preferred compounds of formula XIIa are selected from the following group:

[0145] [ka]

[0146] The medium may additionally contain one or more compounds selected from the following formulae:

[0147] [ka]

[0148] In the formula, L 1 and L 2 has the meaning given in formula I, R 1 and R 2 each independently of one another represents n-alkyl, alkoxy, oxaalkyl, fluoroalkyl or alkenyl, each having up to 6 C atoms, preferably each independently of one another represents 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.

[0149] The 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 subformulae:

[0150] [ka]

[0151] In the formulae, "alkyl" has the meaning given above and preferably denotes methyl, ethyl or propyl.

[0152] The compounds of formula XIV are preferably selected from the following subformulae:

[0153] [ka]

[0154] Highly preferred are compounds of formula XIVd1.

[0155] In still further embodiments, the medium comprises one or more compounds of formula XVI.

[0156] [ka]

[0157] In the formula, R 1 and R 2 have the meanings indicated in formula I and preferably each independently of one another denotes alkyl having 1 to 6 C atoms. L denotes H or F.

[0158] Particularly preferred compounds of formula XVI are those of the subformula below:

[0159] [ka]

[0160] During the ceremony, "Alkyl" and "alkyl * " each independently of one another denotes 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 a straight-chain alkyl group having 1 to 6 C atoms, in particular CH2=CHC2H4, CH3CH=CHC2H4, CH2=CH and CH3CH=CH.

[0161] Particular preference is given to compounds of the formulae XVIb and XVIc. Very particular preference is given to compounds of the following subformulae:

[0162] [ka]

[0163] Highly preferred are compounds of formula XVIc2.

[0164] The medium comprises one or more compounds of the following formula:

[0165] [ka]

[0166] During the ceremony, Each R 1 and R 2 have the meanings indicated in formula I and preferably each independently of one another denotes alkyl having 1 to 6 C atoms. L denotes H or F.

[0167] Highly preferred are compounds of formula XVIIa, wherein L is H. Highly preferred are compounds of formula XVIIb, wherein L is F.

[0168] In one preferred embodiment according to the invention the LC medium comprises in addition to the compounds of the formulae I and H one or more compounds selected from the formulae Y and B.

[0169] [ka]

[0170] In the formula, the individual radicals, which are identical or different at each occurrence, each have the following meanings independently of one another: [ka] [ka] [ka] R 1 , R 2 is R in formula I 1 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-, -CH2O-, -OCH2-, -CO-O-, -O-CO-, -C2F4-, -CF=CF-, -CH=CH-CHO- or a single bond, preferably a single bond; Z z is CHO or a single bond, Y 1 is 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; With the proviso that the compound of formula Y contains at least one substituent L which is F or Cl, preferably F. 1~4 Includes.

[0171] Preferably, the LC medium according to this first preferred embodiment comprises one or more compounds of the formulae I and H, one or more compounds selected from the formulae Z1, Z2 and Z3, and one or more compounds selected from the formulae Y and B.

[0172] The LC medium according to this first preferred embodiment is particularly suitable for use in LC displays of the HB-FFS or PS-HB-FFS mode.

[0173] In a second preferred embodiment according to the invention the LC medium does not comprise a compound of the formula Y or B.

[0174] In the compounds of formula Y and its subformulas, R 1 and R 2 preferably 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.

[0175] In the compounds of formula Y and its subformulas, the group L 1 and L 2 both denote F. In another preferred embodiment of the invention, in the compounds of formula Y and its subformulae, the group L 1 and L 2 One of them represents F and the other represents Cl.

[0176] In a preferred embodiment of the invention, the medium comprises one or more compounds of formula Y selected from the following subformulas:

[0177] [ka]

[0178] 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.

[0179] Preferably the formula Y 1 and Y 2 In the compound of 1 and L 2 Both 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.

[0180] Preferably, the medium comprises one or more compounds of formula Y1 selected from the group consisting of the following subformulae:

[0181] [ka]

[0182] [ka]

[0183] [ka]

[0184] [ka]

[0185] [ka]

[0186] [ka]

[0187] [ka]

[0188] [ka]

[0189] [ka]

[0190] [ka]

[0191] [ka]

[0192] [ka]

[0193] [ka]

[0194] During the ceremony, a represents 1 or 2, "Alkyl" and "alkyl * " each independently represents a linear alkyl group having 1 to 6 C atoms, "alkenyl" denotes a linear alkenyl group having 2 to 6 C atoms, and L 5 represents an H atom or CH3.

[0195] "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-.

[0196] Very preferably, the 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 a H atom.

[0197] More preferably, the medium comprises one or more compounds of formula Y2 selected from the group consisting of the following subformulae:

[0198] [ka]

[0199] [ka]

[0200] [ka]

[0201] [ka]

[0202] [ka]

[0203] [ka]

[0204] [ka]

[0205] During the ceremony, "Alkyl" and "alkyl * " each independently represents a linear alkyl group having 1 to 6 C 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.

[0206] "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-.

[0207] Very preferably, the medium comprises one or more compounds of formula Y2 selected from formulae Y2-2 and Y2-10.

[0208] The proportion of compounds of formula Y1 or any of its subformulas in the medium is preferably between 0 and 10% by weight.

[0209] The proportion of compounds of formula Y2 or any of its subformulas in the medium is preferably between 0 and 10% by weight.

[0210] The total proportion of compounds of the formulae Y1 and Y2 or their subformulae in the medium is preferably between 1 and 20% by weight, very preferably between 2 and 15% by weight.

[0211] Preferably the 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.

[0212] In another preferred embodiment of the invention the medium comprises one or more compounds of formula Y selected from the following subformulae:

[0213] [ka]

[0214] 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 subformulas.

[0215] Preferred compounds of formula Y3 are selected from the group consisting of the following subformulae:

[0216] [ka]

[0217] [ka]

[0218] [ka]

[0219] During the ceremony, "Alkyl" and "Alkyl * " each independently represents a linear alkyl group having 1 to 6 C 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.

[0220] "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-.

[0221] Particularly preferred compounds of formula Y3 are selected from the group consisting of the following subformulae:

[0222] [ka]

[0223] In the formula, "Alkoxy" and "Alkoxy * " each independently of one another preferably denotes straight-chain alkoxy having 3, 4 or 5 C atoms.

[0224] Preferably, in the compounds of formula Y3 and its subformulas, L 1 and L 2 Both represent F. More preferably, in compounds of formula Y3, the group L 1 and L 2 One of these represents F and the other represents Cl.

[0225] The proportion of compounds of formula Y3 or any of its subformulas in the medium is preferably between 1 and 10% by weight, very preferably between 1 and 6% by weight.

[0226] Preferably the medium comprises one, two or three compounds of formula Y3 or a subformula thereof, preferably of formula Y3-6, very preferably of formula Y3-6A.

[0227] In another preferred embodiment of the invention the medium comprises one or more compounds of formula Y selected from the sub-formula Y4.

[0228] [ka]

[0229] 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 ceremony 5 represents F or Cl, preferably F; 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.

[0230] Preferred compounds of formula Y4 are selected from the group consisting of the following subformulae:

[0231] [ka]

[0232] [ka]

[0233] [ka]

[0234] 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 C atoms, (O) represents an oxygen atom or a single bond, and m represents an integer of 1 to 6.

[0235] 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-.

[0236] R preferably represents methyl, ethyl, propyl, butyl, pentyl, hexyl, methoxy, ethoxy, propoxy, butoxy or pentoxy.

[0237] The proportion of compounds of formula Y4 or any of its subformulas in the medium is preferably between 1 and 10% by weight, very preferably between 1 and 6% by weight.

[0238] Particularly preferred compounds are of the following sub-formula:

[0239] [ka]

[0240] During the ceremony, "Alkyl" and "alkyl * " each independently of one another denotes a straight-chain alkyl group having 1 to 6 C atoms, in particular ethyl, propyl or pentyl.

[0241] The use of the following compounds is particularly advantageous:

[0242] [ka]

[0243] In another preferred embodiment of the invention, the medium comprises one or more compounds of formula Y selected from the group consisting of the following subformulae:

[0244] [ka]

[0245] In the formula, R5 is R 1 has one of the meanings given by Y above, "alkyl" denotes a linear alkyl group having 1 to 6 C atoms, L X represents H or F; X represents F, Cl, OCF3, OCHF2 or OCH=CF2; d represents 0 or 1; and z and m each independently represent an integer of 1 to 6.

[0246] R in these compounds 5 is particularly preferably C 2~6 -alkyl or -alkoxy or C 2~6 -alkenyl, 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.

[0247] In the 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.

[0248] In a preferred embodiment of the invention the LC medium comprises one or more compounds of formula B which are selected from the following subformulae:

[0249] [ka]

[0250] In the formula, L 1 , L 2 , R 1 and R 3 has the meaning given in formula B.

[0251] Preferred compounds of formula B1 are selected from the following subformulae:

[0252] [ka]

[0253] In the formula, R 1 and R 3 independently represent a linear alkyl having 1 to 6 C atoms, in which one or more CH2 groups are connected to each other in such a manner 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-, in which one or more H atoms may be replaced by halogen atoms. 1 and R 3 Highly preferred are compounds of formulae B1-1 and B1-2, in which each independently represents an alkyl group that is methyl, ethyl, propyl, butyl, pentyl or hexyl, the alkyl groups being preferably linear. Highly preferred is when one "alkyl" is ethyl and the other "alkyl" is n-pentyl.

[0254] Compounds of formula B1-2 are highly preferred.

[0255] Preferably, the compound of formula B1-1 is selected from the group of the compounds of formulae B1-1-1 to B1-1-11, preferably of formula B1-1-6.

[0256] [ka]

[0257] [ka]

[0258] During the ceremony, "Alkyl" and "alkyl *" each independently represents a linear alkyl group having 1 to 6 C atoms, "Alkenyl" and "alkenyl * " each independently represents a linear alkenyl group having 2 to 6 C atoms, "alkoxy" and "alkoxy * " each independently represent a straight-chain alkoxy group having 1 to 6 C atoms.

[0259] Preferably, the compound of formula B1-2 is selected from the group of the compounds of formulae B1-2-1 to B1-2-10, preferably of formula B1-2-6.

[0260] [ka]

[0261] [ka]

[0262] During the ceremony, "Alkyl" and "alkyl * " each independently represents a linear alkyl group having 1 to 6 C atoms, "Alkenyl" and "alkenyl * " each independently represents a linear alkenyl group having 2 to 6 C atoms, "alkoxy" and "alkoxy * " each independently represent a straight-chain alkoxy group having 1 to 6 C atoms.

[0263] The medium may comprise one or more compounds of formula B1-1A and / or B1-2A.

[0264] [ka]

[0265] 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, optionally substituted by halogen or CN, and preferably represents cyclopropyl, cyclobutyl or cyclopentyl.

[0266] The compounds of formulae B1-1A and / or B1-2A are contained in the medium alternatively or additionally, preferably additionally, to the compounds of formulae B1-1 and B1-2.

[0267] Highly preferred compounds of formula B1-1A and / or B1-2A are:

[0268] [ka]

[0269] In the formula, "alkoxy" is a linear alkoxy group having 1 to 6 C atoms or alternatively -(CH2) n F (wherein n is 2, 3, 4 or 5), preferably C2H4F.

[0270] 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.

[0271] Preferably the medium comprises one, two or three compounds of formula B1 or sub-formulas thereof.

[0272] In a preferred embodiment of the invention, the medium may comprise one or more compounds of formula B2-2.

[0273] [ka]

[0274] 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.

[0275] The compound of formula B2-2 is preferably selected from the group of compounds of formulae B2-2-1 to B2-2-10.

[0276] [ka]

[0277] [ka]

[0278] 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 (wherein n is 2, 3, 4 or 5), preferably C2H4F.

[0279] Particularly preferred compounds of formula B2 are selected from the following subformulae:

[0280] [ka]

[0281] The proportion of compounds of formula B2 or any of its subformulas in the medium is preferably between 1 and 20% by weight, very preferably between 1 and 15% by weight.

[0282] Preferably the LC medium comprises one, two or three compounds of formula B2 or any sub-formula thereof.

[0283] Preferred compounds of formula B3 are selected from the following subformulae:

[0284] [ka]

[0285] In the formula, R 1 has one of the meanings given in formula B3, 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.

[0286] Preferred compounds of formula B3 are selected from the following subformulae:

[0287] [ka]

[0288] 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.

[0289] Compounds of formulae B3-1-1 and B3-2-2 are most preferred.

[0290] In another preferred embodiment the medium comprises one or more compounds of formula B or sub-formulas 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, with the proviso that the dibenzofuran or dibenzothiophene group is a methyl or methoxy group, preferably a methyl group, 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

[0291] The proportion of compounds of the formula B3 or any of its subformulas in the LC medium is preferably between 1 and 20% by weight, very preferably between 1 and 10% by weight.

[0292] Preferably the LC medium comprises one, two or three compounds of formula B3 or any sub-formula thereof.

[0293] Preferably the total proportion of compounds of the formulae Y and B or their subformulae in the medium is between 2 and 25% by weight, very preferably between 3 and 20% by weight.

[0294] Further preferred embodiments are given below:

[0295] The medium comprises one or more compounds of formula Y selected from the following sub-formulae:

[0296] [ka]

[0297] In the formula, R 1 , R 2 , L 1 , L 2 , X, x and Z xhas the meaning given in formula Y, with the proviso that at least one of the rings X is cyclohexenylene.

[0298] Preferably, the group L 1 and L 2 Both of these groups are F. More preferably, the group L 1 and L 2 One of these represents F and the other represents Cl.

[0299] The compound of formula LY is preferably selected from the group consisting of the following subformulae:

[0300] [ka]

[0301] 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 from 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-.

[0302] Highly preferred is a compound of formula LY4.

[0303] Preferably the medium comprises one, two or three compounds of formula LY, very preferably of formula LY4.

[0304] The proportion of the compound of formula LY or any of its subformulas in the medium is preferably between 1 and 10% by weight.

[0305] The medium comprises one or more compounds of formula Y selected from the following sub-formulae:

[0306] [ka]

[0307] 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.

[0308] The compound of formula AY is preferably selected from the group consisting of the following subformulae:

[0309] [ka]

[0310] [ka]

[0311] During the ceremony, R 1 has the meaning given above, "Alkyl" refers to 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.

[0312] 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-.

[0313] The medium does not contain any compound of formula Y, B, LY or AY.

[0314] The medium does not contain compounds having a 1,4-phenylene group substituted with F or Cl at the 2- and 3-positions.

[0315] The medium additionally comprises one or more compounds selected from the following formulae:

[0316] [ka]

[0317] In the formulae, the individual radicals, independently of one another, have the following meanings, which may be identical or different at each occurrence: [ka] During the ceremony, R 0 is R in formula I 1 is one of the meanings given to X 0 is F, Cl, CN, SF5, SCN, NCS, a halogenated alkyl group, a halogenated alkenyl group, a halogenated alkoxy group or a halogenated alkenyloxy group having up to 6 C atoms, and Y 1~6 is H or F, Y 0 is H or CH3.

[0318] Preferred compounds of formula II and III are 0 is H.

[0319] Further preferred compounds of formula II and III are 0 represents alkyl having 1 to 6 C atoms, very preferably ethyl or propyl, and X 0 represents F or OCF3, highly preferably F.

[0320] The medium comprises one or more compounds of formula II selected from the following subformulas:

[0321] [ka]

[0322] [ka]

[0323] In the formula, R 0 and X 0 has the meaning given in formula II.

[0324] Preferred compounds are those of formulae II1, II2 and II3, very preferably those of formulae II1 and II2.

[0325] In the compounds of formula II1 to II7, 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.

[0326] The medium is 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 subformulae:

[0327] [ka]

[0328] [ka]

[0329] In the formula, R 0 and X 0 has the meaning given in formula II.

[0330] Preferred compounds are those of formulae IIA1, IIA2 and IIA3, very preferably those of formulae IIA1 and IIA2.

[0331] In the compounds of formula IIA1 to IIA7, 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.

[0332] The medium comprises one or more compounds of formula III selected from the following subformulas:

[0333] [ka]

[0334] [ka]

[0335] [ka]

[0336] [ka]

[0337] In the formula, R 0 and X 0 has the meaning given in formula II.

[0338] Preferred compounds are of formulae III1, III4, III6, III16, III19 and III20.

[0339] In the compounds of formulae III1 to III21, R 0 preferably denotes alkyl having 1 to 6 C atoms, very preferably ethyl or propyl, and X 0preferably represents F or OCF3, very preferably F, and Y 2 preferably represents F.

[0340] The medium is Y 0 Highly preferably, the medium according to this preferred embodiment comprises one or more compounds of formula III or their sub-formulas as described above and below, wherein is CH3. Highly preferably, the medium according to this preferred embodiment comprises one or more compounds of formula III selected from the following sub-formulas:

[0341] [ka]

[0342] [ka]

[0343] [ka]

[0344] [ka]

[0345] In the formula, R 0 and X 0 has the meaning given in formula III.

[0346] Preferred compounds are of formulae IIIA1, IIIA4, IIIA6, IIIA16, IIIA19 and IIIA20.

[0347] In the compounds of formulae IIIA1 to IIIA21, 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.

[0348] The medium additionally comprises one or more compounds selected from the following formulae:

[0349] [ka]

[0350] During the ceremony, R 0 , X 0 and Y 1~5 has the meaning indicated in formulae II and III, Z 0 represents -C2H4-, -(CH2)4-, -CH=CH-, -CF=CF-, -C2F4-, --CH2CF2-, -CF2CH2-, -CHO-, -OCH2-, -COO- or -OCF2-, and also in formulae V and VI a single bond and in formulae V and VIII -CF2O-, r represents 0 or 1, and s represents 0 or 1.

[0351] The compound of formula IV is preferably selected from the following formulae:

[0352] [ka]

[0353] In the formula, R 0 and X 0 has the meaning given in formulae II and III.

[0354] R 0 preferably represents alkyl having 1 to 6 C atoms. 0 preferably represents F or OCF3, furthermore OCF=CF2 or Cl.

[0355] Compounds of formula IVa are preferably selected from the following subformulae:

[0356] [ka]

[0357] Compounds of formula IVb are preferably selected from the following subformulae:

[0358] [ka]

[0359] Compounds of formula IVc are preferably selected from the following subformulae:

[0360] [ka]

[0361] In the formula, R 0 has the meaning given in formula II and is preferably propyl or pentyl.

[0362] In the mixtures according to the invention, the compound(s) of the formula IVc, in particular of the formula IVc1, are preferably employed in an amount of 1 to 20% by weight, particularly preferably 2 to 15% by weight.

[0363] The compounds of formula V are preferably selected from the following sub-formulae:

[0364] [ka]

[0365] [ka]

[0366] In the formula, R 0 and X 0 has the meaning given in formula II.

[0367] R 0 preferably represents alkyl having 1 to 6 C atoms. 0preferably represents F or OCF3, furthermore OCHF2, CF3, OCF=CF2 and OCH=CF2.

[0368] The compounds of formula VI are preferably selected from the following sub-formulae:

[0369] [ka]

[0370] In the formula, R 0 and X 0 has the meaning given in formula II.

[0371] R 0 preferably represents alkyl having 1 to 6 C atoms. 0 preferably represents F, furthermore OCF3, CF3, CF=CF2, OCHF2 and OCH=CF2.

[0372] The compounds of formula VII are preferably selected from the following subformulae:

[0373] [ka]

[0374] In the formula, R 0 and X 0 has the meaning given above in formula II.

[0375] R 0 preferably represents alkyl having 1 to 6 C atoms. 0 preferably represents F, furthermore OCF3, OCHF2 and OCH=CF2.

[0376] In some embodiments, the medium additionally comprises one or more compounds selected from the following formulae:

[0377] [ka]

[0378] During the ceremony, R 0 and X 0 each independently of one another has one of the meanings given in formula II, Y 1~4 each independently represents H or F, Y 5 represents H or CH3, preferably H, X 0 is preferably F, Cl, CF3, OCF3 or OCHF2, R 0 preferably denotes alkyl, alkoxy, oxaalkyl, fluoroalkyl or alkenyl, each having up to 6 C atoms.

[0379] Very preferably, the medium according to the invention comprises one or more compounds of formula XXa.

[0380] [ka]

[0381] In the formula, R 0 is R in formula I 1 R has the meaning 0 preferably stands for straight-chain alkyl, in particular ethyl, n-propyl, n-butyl and n-pentyl, very particularly preferably n-propyl.

[0382] The compound(s) of the formula XX, in particular of the formula XXa, are preferably used in the mixtures according to the invention in an amount of 0 to 15% by weight, particularly preferably 1 to 10% by weight.

[0383] Very preferably, the medium according to the invention comprises one or more compounds of formula XXIa.

[0384] [ka]

[0385] In the formula, R 0 is R in formula I 1 R has the meaning 0 preferably stands for straight-chain alkyl, in particular ethyl, n-propyl, n-butyl and n-pentyl, very particularly preferably n-propyl.

[0386] The compound(s) of the formula XXI, in particular of the formula XXIa, are preferably used in the mixtures according to the invention in an amount of 1 to 15% by weight, particularly preferably 2 to 10% by weight.

[0387] More preferably, the medium according to the invention comprises one or more compounds of formula XXIIIa.

[0388] [ka]

[0389] In the formula, R 0 is R in formula I 1 R has the meaning 0 preferably stands for straight-chain alkyl, in particular ethyl, n-propyl, n-butyl or n-pentyl, very particularly preferably n-propyl.

[0390] The compound(s) of the formula XXIII, in particular of the formula XXIIIa, are preferably used in the mixtures according to the invention in an amount of 0.5 to 5% by weight, particularly preferably 0.5 to 2% by weight.

[0391] The medium additionally comprises one or more compounds of formula XXIV.

[0392] [ka]

[0393] In the formula, R 0 , X 0 and Y 1~6 has the meaning given in formula III, s represents 0 or 1, [ka] Represents.

[0394] In formula XXIV, X 0 may also represent an alkyl group having 1 to 6 C atoms or an alkoxy group having 1 to 6 C atoms. The alkyl or alkoxy group is preferably linear.

[0395] R 0 preferably represents alkyl having 1 to 6 C atoms. 0 preferably represents F.

[0396] The compounds of formula XXIV are preferably selected from the following subformulae:

[0397] [ka]

[0398] [ka]

[0399] In the formula, R 0 , X 0 and Y 1 has the meaning given in formula III. 0 preferably represents alkyl having 1 to 6 C atoms. 0 preferably represents F, and Y 1 is preferably F.

[0400] [ka]

[0401] R 0 is a straight-chain alkyl or alkenyl having 2 to 6 C atoms.

[0402] The medium may further comprise one or more compounds of the following formulae:

[0403] [ka]

[0404] In the formula, R 1 and X 0 is represented by formula II 0 and X 0 R has the meaning 1 preferably represents alkyl having 1 to 6 C atoms. 0 preferably represents F or Cl. In formula XXIV, X 0 very particularly preferably denotes Cl.

[0405] The medium also includes one or more compounds of the following formula:

[0406] [ka]

[0407] During the ceremony, [ka] Each R 1 and X 0 is represented by formula II 0 and X 0 It has the meaning:

[0408] R 1 preferably represents alkyl having 1 to 6 C atoms. 0 preferably denotes F. The media according to the invention particularly preferably comprise 0 preferably represents F.

[0409] The compound of general formula XXX is advantageously selected from any of the following formulae XXX1 to XXX3, the use of the compound of formula XXX1 being particularly preferred.

[0410] [ka]

[0411] The compound(s) of the formulae XXVI to XXIX are used in the mixtures according to the invention in an amount of 1 to 20% by weight, particularly preferably 1 to 15% by weight. Particularly preferred mixtures comprise at least one compound of the formula XXIX.

[0412] In some further embodiments, the medium comprises one or more compounds of the following formula: TIFF2025513057000173.tif36166

[0413] In the formula, R 1 and R 2 have the meanings indicated in formula I and preferably each independently of one another denotes alkyl having 1 to 6 C atoms.

[0414] Very preferably, the medium according to the invention comprises one or more compounds of formula XXIXa.

[0415] [ka]

[0416] In the formula, 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, very preferably n-propyl.

[0417] The compound(s) of the formula XXIXa are preferably used in the mixtures according to the invention in an amount of 1 to 15% by weight, particularly preferably 2 to 10% by weight.

[0418] The medium may further comprise one or more of the following pyrimidine or pyridine compounds of the formula:

[0419] [ka]

[0420] In the formula, R 1 and X 0 is R in formula II 0 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 comprise 0 preferably denotes F. The compound(s) of the formulae XXXI1-XXXI3 are preferably employed in the mixtures according to the invention in an amount of 1-20% by weight, particularly preferably 1-15% by weight.

[0421] The medium may additionally contain one or more compounds of the following formulae:

[0422] [ka]

[0423] In the formula, L, R 1 and R 2 are Y 1 , R 1 and R 2 has the meaning shown in formula Y. 1 and R 2 preferably denotes alkyl, alkoxy, oxaalkyl, fluoroalkyl or alkenyl, each having up to 6 C atoms.

[0424] Very preferably, the medium according to the invention comprises one or more compounds of formula XXXVa.

[0425] [ka]

[0426] In the formula, "alkyl" denotes a straight-chain alkyl group having 1 to 6 C atoms, in particular ethyl, propyl or pentyl.

[0427] The compound(s) of the formula XXXV, in particular of the formula XXXVa, are preferably employed in the mixtures according to the invention in an amount of 0.5 to 10% by weight, particularly preferably 1 to 5% by weight.

[0428] Further preferred LC media are selected from the following preferred embodiments, including any combination thereof:

[0429] The total content of compounds of formula I in the LC medium is preferably 2-80% by weight, preferably 5-70% by weight, particularly preferably 10-60% by weight, based on the weight of the LC medium.

[0430] It has proven surprisingly advantageous to select the compounds of formula I such that in the LC media of the present invention 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 can be described in the LC media of the present invention by a single structure selected from the following list:

[0431] 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.

[0432] Thus, the LC medium according to the invention may in particular comprise a combination of at least two different compounds of the general formula I selected from the following compounds:

[0433] I-3-9-2-2, I-3-9-3-2, I-3-9-4-5, I-3-9-5-5, I-3-9-6-5, I-3-22-4, I-3-6-3.

[0434] It has been shown that the combination of at least two different compounds of formula I in the LC media according to the invention not only has a much better solubility than a single compound of formula I, but also exhibits a significantly improved stability against UV radiation and high temperatures, thereby synergistically enhancing the stabilizing effect of the compound of general formula H.

[0435] If two compounds of formula I are present in the LC medium according to the invention, their weight ratio, based on the total weight of the two compounds of formula I, is preferably between 10:90 and 90:10, particularly preferably between 20:80 and 80:20, more preferably between 30:70 and 70:30.

[0436] Preferably, the proportion of compounds of formula ST as defined above and listed in table G in the LC medium is between 10 and 2000 ppm by weight, very preferably between 30 and 1000 ppm by weight.

[0437] The preferred content of one or more compounds of formula H in the LC medium depends inter alia on the chemical stability inherent to the LC medium as well as on the properties of the compounds of formula H. 16 O · The compound of formula H, which represents the formula: R, is known as an NO radical type HALS, and is preferably used in a proportion of 50 ppm by weight to 1000 ppm by weight based on the weight of the LC medium. 16 Compounds of the formula H, where represents an H atom, are known as NH radical type HALS and are advantageously used in a proportion of 50 ppm to 2000 ppm by weight, based on the weight of the LC medium.

[0438] The medium comprises two or more, preferably three or more, compounds of formula I or any of its sub-formulas, a compound of formula H and one or more compounds selected from the group consisting of 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, XXXI, XXXI1, XXXI2, XXXI3, XXXII, XXXIII, XXXIV and XXXV and their sub-formulas.

[0439] The medium comprises two or more, preferably three or more, compounds of formula I or any of its sub-formulas, a compound of formula H and one or more compounds selected from the group consisting of formulae Z1, Z2, Z3, Z4, Z5, Y, B, II, III, IV, VI, IX, X, XIV, XVI, XVIIa, XVIIb, XVIIc, XX, XII, XXIII, XXIX, XXXII and XXXV and their sub-formulas.

[0440] The medium does not contain any compound of formula Y, B, AY or LY.

[0441] The medium comprises one or more compounds of formula II, preferably selected from the group consisting of formulae II1, II2 and II3, very preferably from formulae II1 and II2. 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.

[0442] The medium comprises one or more compounds of formula III, preferably selected from the group consisting of formulae III1, III4, III6, III16, III19 and III20, very preferably selected from the group consisting of formulae III1, III6, III16 and III20. The individual concentration of each of these compounds is preferably 2-15% by weight. The total concentration of these compounds is preferably 5-30% by weight.

[0443] The medium comprises one or more compounds of formula IV, preferably selected from formula IVa or IVc, very preferably from formula IVa1 or IVc1, most preferably of formula IVc1. The individual concentration of each of these compounds is preferably 2-15% by weight. The total concentration of these compounds is preferably 5-20% by weight.

[0444] The medium comprises one or more compounds selected from formula VI, preferably formula VIb. The individual concentration of each of these compounds is preferably 1-20% by weight. The total concentration of these compounds is preferably 5-20% by weight.

[0445] The medium comprises one or more compounds selected from formula Z1, preferably from formula Z1-1. The total concentration of these compounds is preferably 1 to 25% by weight.

[0446] The medium comprises one or more compounds of formula Z2, preferably selected from formulae Z2-1 and Z2-2. The total concentration of these compounds is preferably between 2 and 35% by weight, very preferably between 3 and 25% by weight.

[0447] The medium comprises 5 to 20% by weight of a compound of formula Z3, preferably of formula Z3-1.

[0448] The medium comprises 5 to 20% by weight of a compound of formula Z4, preferably of formula Z4-1.

[0449] The medium comprises 10 to 65% by weight, very preferably 20 to 60% by weight, of a compound of formula Z5.

[0450] The medium comprises one or more compounds of formula XII, preferably of formula XIIa or XIIb, very preferably of formula XIIa, most preferably of formula XIIa1. The concentration of these compounds is preferably between 2 and 15% by weight.

[0451] The medium comprises 1 to 15% by weight of the compound of formula XIIb.

[0452] The medium comprises one or more compounds of formula XIV, preferably of formula XIVd, very preferably of formula XIVd1. The concentration of these compounds is preferably between 2 and 10% by weight.

[0453] The medium comprises one or more compounds of formula XVIb, preferably of formulae XVIb1, XVIb2 and / or XVI3, the concentration of which is preferably between 2 and 15% by weight.

[0454] The medium comprises one or more compounds of formula XVIc, preferably of formula XVIc1, XVIc2 and / or XVIc3, the concentration of which is preferably between 2 and 20% by weight.

[0455] The medium comprises one or more compounds of the formula XVIg, preferably of the formulae XVIg1 and / or XVIg2, the concentration of these compounds being preferably between 5 and 25% by weight.

[0456] The medium comprises one or more compounds selected from the group consisting of formulae XVIIa, XVIIb and XVIIc, very preferably of formula XVIIa where L is H and of formula XVIIb where L is F. The total concentration of these compounds is preferably between 0.5 and 5% by weight.

[0457] The medium comprises one or more compounds of formula XX, preferably of formula XXa. The concentration of these compounds is preferably between 2 and 10% by weight.

[0458] The medium comprises one or more compounds of formula XXI, preferably of formula XXIa, the concentration of these compounds being preferably between 2 and 10% by weight.

[0459] The medium comprises one or more compounds of formula XXIII, preferably of formula XXIIIa, the concentration of these compounds being preferably between 0.5 and 5% by weight.

[0460] The medium comprises one or more compounds of formula XXIX, preferably of formula XXIXa, the concentration of these compounds being preferably between 2 and 10% by weight.

[0461] The medium comprises one or more compounds of formula XXXI, preferably of formula XXXIa, the concentration of these compounds being preferably between 2 and 10% by weight.

[0462] The medium comprises one or more compounds of formula XXXII, the concentration of these compounds being preferably between 2 and 10% by weight.

[0463] The medium comprises one or more compounds of formula XXXII, the concentration of these compounds being preferably between 2 and 10% by weight.

[0464] The medium comprises one or more compounds of formula XXXV, preferably of formula XXXVa, the concentration of these compounds being preferably between 1 and 5% by weight.

[0465] The medium comprises two or more, preferably three or more, compounds of the formula I, preferably of the formula I-2-6, a compound of the formula H, 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, XXXII and XXXV or subformulas thereof.

[0466] The medium comprises two or more, preferably three or more, compounds of the formula I, preferably of the formula I-2-6, a compound of the formula H, 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, one or more compounds selected from the group consisting of the formulae XIIb, XVIb, XVIc, XVIIa, XVIIb, XVIIc, XXXII and XXXVa or subformulas thereof.

[0467] The medium comprises two or more, preferably three or more, compounds of formula I, preferably of formula I-2-6, a compound of formula H, one or more compounds selected from the group consisting of formulae Z1, Z2, Z3, Z4 and Z4 or subformulas thereof, one or more compounds of formula Y, preferably selected from the group consisting of Y1 and Y2, one or more compounds selected from the group consisting of formula XIV or subformulas thereof, one or more compounds selected from the group consisting of formulae II, III, IV, VI, XX, XXIII and XXIX or subformulas thereof, one or more compounds selected from the group consisting of formulae XII, XVI, XVIIa, XVIIb, XVIIc, XXXII and XXXV or subformulas thereof.

[0468] The medium comprises two or more, preferably three or more, compounds of the formula I, preferably of the formula I-2-6, a compound of the formula H, 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, one or more compounds selected from the group consisting of the formulae XIIb, XVIb, XVIc, XVIIa, XVIIb, XVIIc, XXXII and XXXVa or subformulas thereof.

[0469] Besides the compounds of the formulae I and H, the 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, XXXI, XXXII and XXIV or their sub-formulae.

[0470] Besides the compounds of the formulae I and H, the 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, XXXI, XXXII and XXXIV or their sub-formulas.

[0471] The proportion of compounds of formula I or any of its subformulas in the medium is between 1 and 30% by weight, very preferably between 2 and 25% by weight, most preferably between 2 and 20% by weight.

[0472] The proportion of compounds of the formulae Z1, Z2 and Z3 or their subformulas in the overall mixture is between 10 and 65%, very preferably between 20 and 60%.

[0473] The proportion of compounds of formula Y or any of its sub-formulas in the overall mixture is between 1 and 20%, very preferably between 2 and 15%.

[0474] The proportion of compounds of formula B or any of its sub-formulas in the overall mixture is between 1 and 20%, very preferably between 2 and 18%.

[0475] The proportion of compounds of the formulae II, III, IV-VIII, XVIII-XXIII and XXVII-XXX in the entire mixture is 30-60% by weight.

[0476] The proportion of the compounds of the formulae IX to XV in the entire mixture is 40 to 70% by weight.

[0477] The proportion of the compounds of the formulae XIV, XVIIa-c and XXXII-XXXV in the entire mixture is 0.5-15% by weight.

[0478] In this application, the term "alkyl" or "alkyl * (Alkyl * )" embraces straight-chain and branched alkyl groups having 1 to 6 carbon atoms, in particular the straight-chain groups methyl, ethyl, propyl, butyl, pentyl and hexyl. Groups having 2 to 5 carbon atoms are generally preferred.

[0479] The term "alkenyl" or "alkenyl * (Alkenyl * )" includes linear and branched alkenyl groups having 2 to 6 carbon atoms, in particular linear groups. Preferred alkenyl groups are C2-C7-1E-alkenyl, C4-C6-3E-alkenyl, in particular C2-C6-1E-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, in particular CH2=CH, CH3CH=CH, are generally preferred.

[0480] 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, however other positions of the fluorine are not excluded.

[0481] The term "oxaalkyl" or "alkoxy" preferably refers to a compound of the formula C n H 2n+1 -O-(CH2) m where 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 further O atoms such that the oxygen atoms are not directly linked to each other.

[0482] 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 changed in a desired manner. For example, 1E-alkenyl groups, 3E-alkenyl groups, 2E-alkenyloxy groups, etc. generally have shorter address times, improved nematic tendency, elastic constant k compared to alkyl and alkoxy groups. 33 (bend) and k 11 (spray) ratio. 4-alkenyl groups, 3-alkenyl groups, etc. generally have lower threshold voltages and k 33 / k 11 The mixtures according to the invention are distinguished in particular by high values ​​of Δε and therefore have significantly faster response times than the mixtures from the prior art.

[0483] 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.

[0484] The appropriate mixing ratio within the ranges indicated above can be readily determined in each case.

[0485] The total amount of the compounds of the above formula in the liquid crystal medium according to the present invention is not important.Therefore, the mixture may contain one or more additional components for the purpose of optimizing various properties.However, the higher the total concentration of the compounds of the above formula, the greater the observed effect on the desired improvement of the properties of the medium.

[0486] In a particularly preferred embodiment the liquid crystal media according to the invention have 0 The compounds of the formulae IV to VIII (preferably IV and V) are included, where F, OCF3, OCHF2, OCH=CF2, OCF=CF2 or OCF2-CF2H. The favorable synergism with the compounds of the formulae I, II and III results in particularly advantageous properties. In particular, mixtures containing the compounds of the formulae I, H, II and III are distinguished by their low threshold voltage.

[0487] The individual compounds of the abovementioned formulae and their subformulas which can be used in the liquid-crystalline media according to the invention are either known or can be prepared analogously to known compounds.

[0488] The present invention also relates to a process for the preparation of 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, XVI, XVIIa, XVIIb, XVIIc, XX, XXIII, XXIX, XXXII and XXXV.

[0489] In another preferred embodiment of the invention the liquid crystal medium additionally comprises one or more polymerisable compounds. The polymerisable compounds are preferably selected from the group consisting of

[0490] [ka]

[0491] In the formulae, the individual radicals, identically or differently at each occurrence, each independently of one another have the following meanings: R a and R b is P, P-Sp-, H, F, Cl, Br, I, -CN, -NO2, -NCO, -NCS, -OCN, -SCN, SF5, or linear or branched alkyl having 1 to 25 C atoms (provided that in addition, one or more non-adjacent CH2 groups are each independently -C(R 0 )=C(R 00 )-, -C≡C-, -N(R 00 )-, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O-, where the O and / or S atoms 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 them 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 -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 given 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 each other, 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.

[0492] 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 (in which one or more CH groups may be replaced by N), cyclohexane-1,4-diyl (in which 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, all of which are compounds which may be unsubstituted or mono- or polysubstituted by L as defined above.

[0493] Particularly preferred compounds of formula M are those in which B 1 and B. 2 each independently represents 1,4-phenylene, 1,3-phenylene, naphthalene-1,4-diyl, or naphthalene-2,6-diyl.

[0494] Highly preferred compounds of formula M are selected from the following formulae:

[0495] [ka]

[0496] [ka]

[0497] [ka]

[0498] [ka]

[0499] [ka]

[0500] [ka]

[0501] In the formulae, the individual radicals, identically or differently at each occurrence, each independently of one another have the following meanings: 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 the characters is R aa provided that the group P 1 -Sp 1 -, P 2 -Sp 2 - and P 3 -Sp 3 -At least one 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 from 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 be independently -C(R 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, 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 where 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.

[0502] Compounds of formulae M2 and M13 are particularly preferred.

[0503] More preferred are the trireactive compounds M15 to M31, in particular M17, M18, M19, M22, M23, M24, M25, M30 and M31.

[0504] 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 and is preferably F, Cl, CN, NO2, CH3, C2H5, C(CH3)3, CH(CH3)2, CH2CH(CH3)C2H5, OCH3, OC2H5, COCH3, COC2H5, COOCH3, COOC2H5, CF3, OCF3, OCHF2, OC2F5 or P-Sp-, very preferably F, Cl, CN, CH3, C2H5, OCH3, COCH3, OCF3 or P-Sp-, more preferably F, Cl, CH3, OCH3, COCH3 or OCF3, in particular F or CH3.

[0505] 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.

[0506] Further preferred compounds of the formulae M1 to M31 are those in which Sp 1 , Sp 2 and Sp 3 is a single bond.

[0507] Further preferred compounds of the 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.

[0508] 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 Ga-(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 linkage to a benzene ring and is -O-, -O-CO-, -CO-O, -O-CO-O- or a single bond).

[0509] Particular preference is given to liquid-crystalline media which comprise one, two or three polymerisable compounds of the formula M, preferably selected from the formulae M1 to M31.

[0510] More preferably, the liquid crystal medium according to the invention comprises one or more polymerizable compounds selected from table E below.

[0511] The proportion of polymerizable compounds, preferably selected from formula M and table E, in the liquid crystal medium is preferably 0.01 to 5%, very preferably 0.05 to 1%, most preferably 0.1 to 0.5%.

[0512] It has been observed that the addition of one or more polymerizable compounds, such as those selected from formula M and table E, to the liquid crystal medium results 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 low pretilt angles that are stable after UV exposure, high reliability, high VHR values ​​after UV exposure, and high birefringence. By appropriate selection of the polymerizable compounds, it is possible to increase the absorption of the liquid crystal medium at longer UV wavelengths, so that such longer UV wavelengths can be used for polymerization, which is advantageous for the display manufacturing process.

[0513] The polymerizable group P is, for example, a group suitable for polymerization reactions, such as free-radical or ionic chain polymerization, polyaddition or polycondensation, or polymer-analogous reactions, for example 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 also groups suitable for ring-opening polymerization, such as, for example, oxetane or epoxide groups, are particularly preferred.

[0514] The preferred group P is CH2=CW 1 -CO-O-, CH2=CW 1 -CO-, [ka] CH2=CW 2 -(O) k3 -, C.W. 1 =CH-CO-(O) k3 -, C.W. 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 -, H.W. 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 stands for H, F, Cl, CN, CF3, phenyl or alkyl having 1 to 5 C atoms, in particular H, F, Cl or CH3, 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 C atoms, W 7 and W 8 each independently of one another represents H, Cl or an 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 of one another represent 0 or 1, k3 preferably represents 1 and k4 represents an integer from 1 to 10.

[0515] Highly preferred groups P are CH2=CW 1 -CO-O-, CH2=CW 1 -CO-, [ka] CH2=CW 2 -O-, CH2=CW 2 -, C.W. 1 =CH-CO-(O) k3 -, C.W. 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 stands for H, F, Cl, CN, CF3, phenyl or alkyl having 1 to 5 C atoms, in particular H, F, Cl or CH3, 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 C atoms, W 7 and W 8 each independently represents H, Cl, or an 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.

[0516] 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:

[0517] 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.

[0518] When Sp is different from a single bond, it is preferably of the formula Sp"-X", so that each group P-Sp- corresponds to the formula P-Sp"-X"-, in which: Sp" represents an 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 -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 used to replace the O and / or S atoms in such a way that they 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.

[0519] X″ is preferably —O—, —S—, —CO—, —COO—, —OCO—, —O—COO—, —CO—NR 0 -, -NR 0 -CO-, -NR 0 -CO-NR 00 - or a single bond.

[0520] 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 In the formula, 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 given in formula M above.

[0521] 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.

[0522] 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.

[0523] For the production of PSA displays, the polymerizable compounds contained in the liquid crystal medium are polymerized or (if a 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 the application of a voltage to the electrodes.

[0524] The structure of the PSA display according to the invention corresponds to the usual configuration of PSA displays as described in the prior art cited at the beginning. Configurations without protrusions are preferred, in particular those in which the electrodes on the color filter side are not structured and only the electrodes on the TFT side have slots. Particularly suitable and preferred electrode structures for PS-VA displays are described, for example, in US 2006 / 0066793 A1.

[0525] The combination of the compounds of the abovementioned preferred embodiments with the abovementioned polymerizable compounds in the liquid-crystalline media according to the invention always leads to high clearing points and high VHR values ​​at the same time as low threshold voltages, low rotational viscosities and very good low-temperature stability.

[0526] By using a liquid crystal medium containing a polymerizable compound, particularly low pretilt angles can be rapidly established in PSA displays. In particular, the liquid crystal medium also shows significantly reduced response times, especially grey-scale response times, in PSA displays compared to media from the prior art.

[0527] Liquid crystal media having a nematic liquid crystal phase, preferably no chiral liquid crystal phase, are generally preferred.

[0528] 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 to electro-optical displays, in particular of the aforementioned types and comprising a liquid-crystalline medium according to the invention 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.

[0529] The invention also relates to an electro-optical display, e.g. an STN or MLC display, having two flat parallel outer plates which together with a frame form a cell, integrated nonlinear 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.

[0530] 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, thermal and UV stability and high optical anisotropy is much superior to prior materials from the prior art.

[0531] In particular, the compounds of formula I in combination with compounds of formula Y and / or B and additionally with compounds selected from the formulae II to XXXV or their subformulae, result in low rotational viscosity and a ratio γ1 / k 11 The liquid crystals exhibit a moderate positive dielectric anisotropy while maintaining a low value of the dielectric constant ε perpendicular to the longitudinal axis of the liquid crystal molecules. ⊥ This leads to liquid crystal media with increased luminance. This allows liquid crystal displays, especially in FFS, HB-FFS, XB-FFS and IPS modes, with high luminance and transmittance as well as low response times.

[0532] The liquid-crystalline media according to the invention are suitable for mobile applications, such as, for example, mobile phones and PDAs, and for TFT applications. Furthermore, the liquid-crystalline media according to the invention are particularly suitable for use in FFS, HB-FFS, XB-FFS and IPS displays which are based on dielectrically positive liquid crystals.

[0533] The liquid-crystalline media according to the invention retain a nematic phase down to -20°C, preferably down to -30°C, particularly preferably down to -40°C, and a clearing point above 75°C, preferably above 80°C, while at the same time achieving a rotational viscosity γ1 of 110 mPa·s or less, particularly preferably 100 mPa·s or less, which allows for excellent MLC displays with fast response times. The rotational viscosity is determined at 20°C.

[0534] The dielectric anisotropy Δε of the liquid-crystalline medium according to the invention at 20° C. and 1 kHz is preferably greater than or equal to +1.5, very preferably from +2 to +6.

[0535] The birefringence Δn at 20° C. of the liquid crystal medium according to the invention is preferably from 0.08 to 0.15, very preferably from 0.1 to 0.14.

[0536] 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 and very preferably 60 mPs·sec or less.

[0537] The ratio γ1 / k of the liquid-crystalline media according to the invention 11 (where γ1 is the rotational viscosity γ1, and k 11 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, and most preferably 4.0 mPs·sec / pN or less.

[0538] The range of the nematic phase of the liquid-crystalline medium 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.

[0539] It goes without saying that through a suitable selection of the components of the liquid-crystalline media according to the invention, it is also possible to achieve a higher clearing point (for example above 100° C.) at a higher threshold voltage or a lower clearing point at a lower threshold voltage, while retaining other advantageous properties. It is likewise possible to obtain liquid-crystalline media with a higher Δε and thus a lower threshold voltage, with a correspondingly only slightly increased viscosity. The MLC displays according to the invention preferably operate at the first transmission minimum of Gooch and Tarry [CH Gooch and HA Tarry, Electron. Lett. vol. 10, pp. 2-4, 1974; CH Gooch and HA Tarry, Appl. Phys. vol. 8, pp. 1575-1584, 1975], in which case a lower dielectric anisotropy is sufficient to obtain the same threshold voltage as a similar display at the second minimum, in addition to particularly favorable electro-optical properties, such as, for example, high steepness of the characteristic lines and low angle dependence of the contrast (DE 30 22 818). For this reason, at the first minimum, the use of the mixtures according to the invention 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, the skilled person can set the required birefringence for a prespecified layer thickness of an MLC display in a simple and conventional manner.

[0540] 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:

[0541] [ka] or cyanophenylcyclohexanes of the formula

[0542] [ka] It has been shown that the liquid-crystalline media according to the invention containing the 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 I, ST-1, ST-2, RV, IA and IB instead of the compounds of the formulae I, ST-1, ST-2, RV, IA and IB.

[0543] 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.

[0544] 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, which term is used in the broad sense to include all derivatives and modifications of MLC displays, in particular matrix display elements based on polysilicon TFTs or MIMs.

[0545] However, a major difference between the display according to the invention and hitherto conventional displays based on twisted nematic cells lies in the choice of liquid crystal parameters of the liquid crystal layer.

[0546] The liquid crystal media that can be used according to the invention are prepared in a manner conventional per se, 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. In general, the desired amount of the component that is used in a 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 remove the solvent again after thorough mixing, for example by distillation.

[0547] The LC medium may also contain further additives known to those skilled in the art and described in the literature, such as, for example, 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 set out in Tables C and D below.

[0548] In a preferred embodiment of the invention the LC medium comprises one or more further stabilizers, preferably selected from the group consisting of the following formulae:

[0549] [ka]

[0550] During the ceremony, n is an integer of 1 to 6, and preferably 3.

[0551] Highly preferred stabilizers are selected from the group consisting of the following formulas:

[0552] [ka]

[0553] In a preferred embodiment the LC medium comprises one or more stabilizers selected from the group consisting of the formulae S1-1, S2-1.

[0554] In a preferred embodiment the LC medium comprises one or more stabilizers selected from Table D.

[0555] Preferably the proportion of stabilizers such as those of formulae S1 to S3 in the LC medium is between 10 and 2000 ppm, very preferably between 30 and 1000 ppm.

[0556] In another preferred embodiment the LC medium according to the invention comprises a self-alignment (SA) additive, preferably in a concentration of 0.1-2.5%. 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.

[0557] In a preferred embodiment, the SA-FFS, SA-HB-FFS or SA-XB-FFS display according to the invention does not comprise a polyimide alignment layer. In another preferred embodiment, the SA-FFS, SA-HB-FFS or SA-XB-FFS display according to the preferred embodiment comprises a polyimide alignment layer.

[0558] Preferred 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.

[0559] 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.

[0560] Suitable SA additives for inducing homeotropic alignment, particularly for use in SA-VA mode displays, are disclosed, for example, in US Patent Application Publication No. 2013 / 0182202, US Patent Application Publication No. 2014 / 0838581, US Patent Application Publication No. 2015 / 0166890 and US Patent Application Publication No. 2015 / 0252265.

[0561] In another preferred embodiment, the LC medium or the 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.

[0562] It is further possible to add to the liquid-crystalline medium, for example 0 to 15% by weight of pleochroic dyes, furthermore nanoparticles, conductive salts, preferably ethyl dimethyldodecylammonium 4-hexoxybenzoate, tetrabutylammonium tetraphenylborate or complex salts of crown ethers (for example Haller et al., Mol. Cryst. Liq. Cryst. Vol. 24, pp. 249-258 (1973)), substances which increase the electrical conductivity or which modify the dielectric anisotropy, the viscosity and / or the orientation of the nematic phase. Substances of this type are described, for example, in DE-A-22 09 127, DE-A-22 40 864, DE-A-23 21 632, DE-A-23 38 281, DE-A-24 50 088, DE-A-26 37 430 and DE-A-28 53 728.

[0563] In the present invention and the following examples, the structures of the liquid crystal compounds are represented by acronyms, and the conversion to chemical formulas is performed 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 H2 m-1 , C n H2 n-1 and C l H 2l-1 are linear alkyl or alkylene radicals, respectively, with n, m and l C 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 of the ring elements of the core of the compounds, Table B lists the bridging units and Table C lists the meaning of the symbols of the left and rightmost groups of the molecules. The acronyms consist of the code of the ring element with any linking group, followed by the code of the first hyphen and the leftmost group, and the code of the second hyphen and the rightmost group. Table D shows exemplary structures of the compounds with their respective abbreviations.

[0564] <Table A: Ring elements>

[0565] [Table 1]

[0566] [Table 2]

[0567] [Table 3]

[0568] <Table B: Cross-linking units>

[0569] [Table 4]

[0570] <Table C: Terminal group>

[0571] [Table 5]

[0572] [Table 6]

[0573] In the table, n and m are each integers, and the three dots "..." are places for other abbreviations from this table.

[0574] The following abbreviations are used: (n, m, k and l are each independently an integer, preferably 1 to 9, preferably 1 to 7, and 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".)

[0575] Preferred mixture components are shown in Tables D and E.

[0576]

[0577] [Table 7]

[0578] [Table 8]

[0579] 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 or 6.

[0580] [Table 9]

[0581] [Table 10]

[0582] [Table 11]

[0583] [Table 12]

[0584] [Table 13]

[0585] [Table 14]

[0586] [Table 15]

[0587] [Table 16]

[0588] [Table 17]

[0589] [Table 18]

[0590] [Table 19]

[0591] Particularly preferred are liquid crystal media which contain, in addition to the compounds of the formulae IA, IIA, IB and IIB, at least one, two, three or more compounds from Table E.

[0592] Table F shows dopants which can generally be added to the liquid-crystalline media according to the invention. The liquid-crystalline media preferably contain from 0 to 10% by weight, in particular from 0.01 to 5% by weight, particularly preferably from 0.01 to 3% by weight, of dopant.

[0593] [Table 20]

[0594] [Table 21]

[0595] Stabilisers which can additionally be added to the liquid crystal media according to the invention in amounts of, for example, 0 to 10% by weight are mentioned below.

[0596] [Table 22]

[0597] [Table 23]

[0598] [Table 24]

[0599] [Table 25]

[0600] [Table 26]

[0601] [Table 27]

[0602] Table H shows exemplary reactive mesogenic compounds (RM) that can be used in the liquid crystal media according to the present invention.

[0603]

Table 28

[0604]

Table 29

[0605]

Table 30

[0606]

Table 31

[0607]

Table 32

[0608]

Table 33

[0609]

Table 34

[0610]

Table 35

[0611]

Table 36

[0612]

Table 37

[0613]

Table 38

[0614]

Table 39

[0615]

Table 40

[0616]

Table 41

[0617]

Table 42

[0618]

Table 43

[0619]

Table 44

[0620]

Table 45

[0621]

Table 46

[0622]

Table 47

[0623]

Table 48

[0624] [Table 49]

[0625] 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-143, of which 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-64, RM-74, RM-76, RM-88, RM-102, RM-103, RM-109, RM-117, RM-120, RM-121 and RM-122 are particularly preferred.

[0626] 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.

[0627] [Table 50]

[0628] [Table 51]

[0629] [Table 52]

[0630] [Table 53]

[0631] [Table 54]

[0632] [Table 55]

[0633] [Table 56]

[0634] [Table 57]

[0635] [Table 58]

[0636] [Table 59]

[0637] In a preferred embodiment the LC media according to the invention, the SA-FFS, SA-HB-FFS and SA-XB-FFS displays comprise one or more SA additives selected from the formulae SA-1 to SA-34, preferably from the formulae SA-14 to SA-34, very preferably from the formulae SA-20 to SA-28, most preferably of formula SA-20, in combination with one or more RM of formula I.

[0638] The following mixture examples are intended to illustrate the invention without limiting it.

[0639] Above and below, the percentage data represent weight percent. All temperatures are given in degrees Celsius. mp represents the melting point and cl.p. represents the clearing point. Furthermore, C is the crystalline state, N is the nematic phase, S is the smectic phase, and I is the isotropic phase. The data between these symbols represent the transition temperatures. Additionally, the following symbols are used:

[0640] V020℃ Freedericks capacitance threshold voltage [V], V 10 Voltage at 10% transmission [V], n e The extraordinary refractive index measured at 20°C and 589 nm, n0Normal refractive index measured at 20°C and 589 nm, Δn is the optical anisotropy measured at 20 °C and 589 nm; ε ⊥ The permittivity (or "dielectric constant") perpendicular to the long axis of the molecule at 20°C and 1 kHz, ε ∥ The permittivity (or "dielectric constant") parallel to the long axis of the molecule at 20°C and 1 kHz, Δε dielectric anisotropy at 20 °C and 1 kHz, cl.p. or T(N,I) clearing point [℃], ν Flow viscosity measured at 20℃ [mm 2 ·s -1 ], γRotational viscosity measured at 120℃ [mPa s], k 11 Elastic constant for "splay" deformation at 20°C [pN], k 22 Elastic constant for "twist" deformation at 20°C [pN], k 33 The elastic constant for "bend" deformation at 20°C [pN], and LTS (low-temperature stability) Low-temperature stability of a phase in bulk [time] VHR (voltage holding ratio) Voltage holding ratio.

[0641] 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 20°C. EXAMPLES

[0642] <Basic mixture M1> The nematic LC mixture is formulated as follows:

[0643] [Table 60]

[0644] <Mixture Example 1 (stabilized with compound of formula H-3-1)> Nematic LC mixtures according to the invention are formulated as follows:

[0645] [Table 61]

[0646] Addition of 100 ppm of compound of formula H-3-1 significantly increased VHR after UV exposure compared to unstabilized mixture M1. 100 is significantly improved.

[0647] <Basic mixture M2> The nematic LC mixture is formulated as follows:

[0648] [Table 62]

[0649] <Mixture Example 2 (stabilized with compound of formula H-3-1)> Nematic LC mixtures according to the invention are formulated as follows:

[0650] [Table 63]

[0651] Addition of 150 ppm of compound of formula H-3-3 increased VHR after UV exposure compared to unstabilized mixture M2. 100 is significantly improved.

[0652] <Basic mixture M3> The nematic LC mixture is formulated as follows:

[0653] [Table 64]

[0654] <Mixture Example 3 (stabilized with compound of formula H-3-7)> Nematic LC mixtures according to the invention are formulated as follows:

[0655] [Table 65]

[0656] Addition of 150 ppm of compound of formula H-3-7 significantly increased the VHR after UV exposure compared to unstabilized mixture M3. 100 is significantly improved.

[0657] <Basic mixture M4> The nematic LC mixture is formulated as follows:

[0658] [Table 66]

[0659] <Mixture Example 4 (stabilized with compound of formula H-3-8)> Nematic LC mixtures according to the invention are formulated as follows:

[0660] [Table 67]

[0661] Addition of 150 ppm of compound of formula H-3-8 significantly increased VHR after UV exposure compared to unstabilized mixture M4. 100 is significantly improved.

[0662] <Basic mixture M5> The nematic LC mixture is formulated as follows:

[0663] [Table 68]

[0664] <Mixture Example 5 (stabilized with compound of formula H-3-10)> Nematic LC mixtures according to the invention are formulated as follows:

[0665] [Table 69]

[0666] Addition of 30 ppm of compound of formula H-3-10 significantly increased VHR after UV exposure compared to unstabilized mixture M5. 100 is significantly improved.

[0667] <Basic mixture M6> The nematic LC mixture is formulated as follows:

[0668] [Table 70]

[0669] <Mixture Example 6 (stabilized with compound of formula H-3-2)> Nematic LC mixtures according to the invention are formulated as follows:

[0670] [Table 71]

[0671] Addition of 20 ppm of compound of formula H-3-2 significantly increased the VHR after UV exposure compared to unstabilized mixture M6. 100 is significantly improved.

[0672] <Basic mixture M7> The nematic LC mixture is formulated as follows:

[0673] [Table 72]

[0674] <Mixture Example 7 (stabilized with compound of formula H-3-4)> Nematic LC mixtures according to the invention are formulated as follows:

[0675] [Table 73]

[0676] Addition of 20 ppm of compound of formula H-3-4 significantly increased VHR after UV exposure compared to unstabilized mixture M7. 100 is significantly improved.

[0677] <Basic mixture M8> The nematic LC mixture is formulated as follows:

[0678] [Table 74]

[0679] <Mixture Example 8 (stabilized with compound of formula H-3-7)> Nematic LC mixtures according to the invention are formulated as follows:

[0680] [Table 75]

[0681] Addition of 120 ppm of compound of formula H-3-7 significantly increased VHR after UV exposure compared to unstabilized mixture M8. 100 is significantly improved.

[0682] <Basic mixture M9> The nematic LC mixture is formulated as follows:

[0683] [Table 76]

[0684] <Mixture Example 9 (stabilized with compound of formula H-3-7)> Nematic LC mixtures according to the invention are formulated as follows:

[0685] [Table 77]

[0686] Addition of 100 ppm of compound of formula H-3-7 significantly increased VHR after UV exposure compared to unstabilized mixture M9. 100 is significantly improved.

[0687] <Basic mixture M10> The nematic LC mixture is formulated as follows:

[0688] [Table 78]

[0689] <Mixture Example 10 (stabilized with compound of formula H-3-1)> Nematic LC mixtures according to the invention are formulated as follows:

[0690] [Table 79]

[0691] Addition of 100 ppm of compound of formula H-3-1 significantly increased VHR after UV exposure compared to unstabilized mixture M10. 100 is significantly improved.

[0692] <Basic mixture M11> The nematic LC mixture is formulated as follows:

[0693] [Table 80]

[0694] <Mixture Example 11 (stabilized with compound of formula H-3-3)> Nematic LC mixtures according to the invention are formulated as follows:

[0695] [Table 81]

[0696] Addition of 100 ppm of compound of formula H-3-3 significantly increased the VHR after UV exposure compared to unstabilized mixture M11. 100 is significantly improved.

[0697] <Basic mixture M12> The nematic LC mixture is formulated as follows:

[0698] [Table 82]

[0699] <Mixture Example 12 (stabilized with compound of formula H-3-3)> Nematic LC mixtures according to the invention are formulated as follows:

[0700] [Table 83]

[0701] Addition of 100 ppm of compound of formula H-3-3 significantly increased VHR after UV exposure compared to unstabilized mixture M12. 100 is significantly improved.

[0702] <Basic mixture M13> The nematic LC mixture is formulated as follows:

[0703] [Table 84]

[0704] [ka]

[0705] <Mixture Example 13 (stabilized with compound of formula H-3-6)> Nematic LC mixtures according to the invention are formulated as follows:

[0706] [Table 85]

[0707] Addition of 10 ppm of compound of formula H-3-6 significantly increased the VHR after UV exposure compared to unstabilized mixture M13. 100 is significantly improved.

[0708] <Basic mixture M14> The nematic LC mixture is formulated as follows:

[0709] [Table 86]

[0710] <Mixture Example 14 (stabilized with compound of formula H-3-6)> Nematic LC mixtures according to the invention are formulated as follows:

[0711] [Table 87]

[0712] Addition of 10 ppm of compound of formula H-3-6 significantly increased the VHR after UV exposure compared to unstabilized mixture M14.100 is significantly improved.

[0713] <Basic mixture M15> The nematic LC mixture is formulated as follows:

[0714] [Table 88]

[0715] [ka]

[0716] <Mixture Example 15 (stabilized with compound of formula H-3-5)> Nematic LC mixtures according to the invention are formulated as follows:

[0717] [Table 89]

[0718] Addition of 10 ppm of compound of formula H-3-5 significantly increased VHR after UV exposure compared to unstabilized mixture M15. 100 is significantly improved.

[0719] <Basic mixture M16> The nematic LC mixture is formulated as follows:

[0720] [Table 90]

[0721] [ka]

[0722] <Mixture Example 16 (stabilized with compound of formula H-3-1)> Nematic LC mixtures according to the invention are formulated as follows:

[0723] [Table 91]

[0724] Addition of 100 ppm of compound of formula H-3-1 significantly increased VHR after UV exposure compared to unstabilized mixture M16. 100 is significantly improved.

[0725] <Basic mixture M17> The nematic LC mixture is formulated as follows:

[0726] [Table 92]

[0727] [ka]

[0728] <Mixture Example 17 (stabilized with compound of formula H-3-3)> Nematic LC mixtures according to the invention are formulated as follows:

[0729] [Table 93]

[0730] Addition of 100 ppm of compound of formula H-3-5 significantly increased VHR after UV exposure compared to unstabilized mixture M17. 100 is significantly improved.

[0731] <Basic mixture M18> The nematic LC mixture is formulated as follows:

[0732] [Table 94]

[0733] [ka]

[0734] <Mixture Example 18 (stabilized with compound of formula H-3-4)> Nematic LC mixtures according to the invention are formulated as follows:

[0735] [Table 95]

[0736] Addition of 10 ppm of compound of formula H-3-4 significantly increased the VHR after UV exposure compared to unstabilized mixture M18. 100 is significantly improved.

Claims

1. A liquid crystal medium characterized by containing two or more compounds of formula I and one or more compounds of formula H. 【Chemistry 1】 (In the formula, each substituent has the following meaning: R １ and R ２ Each of these independently comprises an alkyl or alkoxy group having a hydrogen atom and 1 to 12 carbon atoms, or an alkenyl or alkenyloxy group having 2 to 12 carbon atoms (one or more non-adjacent CH groups in the said group). ２ The groups are formed so that the oxygen atoms are not directly bonded to each other, such as -C≡C- and -CF ２ O-, -OCF ２ -, -CH=CH-, 【Chemistry 2】 It may be substituted with -O-, -CO-O- or -O-CO-, and one or more H atoms in the group may be replaced with halogen atoms.) or a cycloalkyl or cycloalkoxy group having 3 to 12 C atoms (one or more H atoms in the group may be replaced with halogen atoms), A ０ 、 A １ 、 A ２ are each independently of the others phenylene-1,4-diyl (wherein in addition, one or two CH groups may be replaced by N, and one or more H atoms are halogen, CN, CH ３ , CHF ２ , CH ２ F, CF ３ , OCH ３ , OCHF ２ or OCF ３ and may be replaced. ), cyclohexane-1,4-diyl (wherein in addition, one or two non-adjacent CH ２ groups may be independently replaced by O and / or S, and one or more H atoms may be replaced by F. ), cyclohexene-1,4-diyl, bicyclo[1.1.1]pentane-1,3-diyl, bicyclo[2.2.2]octane-1,4-diyl, spiro[3.3]heptane-2,6-diyl, tetrahydropyran-2,5-diyl or 1,3-dioxane-2,5-diyl, Z １ and Z ２ Each of them is independent of the other, -CF ２ O-, -OCF ２ -ien-CH ２ O-, -OCH ２ -, -CO-O-, -O-CO-, -C ２ H ４ -, -C ２ F ４ -, -CF ２ CH ２ -ien-CH ２ CF ２ -, -CFHCFH-, -CFHCH ２ -ien-CH ２ CFH-, -CF ２ CFH-, -CFHCF ２ -, -CH=CH-, -CF=CH-, -CH=CF-, -CF=CF-, -C≡C- or single bond, k and l each independently represent 0, 1, 2, or 3. 【Transformation 3】 (In the formula, R １１ Each of these independently represents an alkyl group having an H atom, a F atom, and 1 to 20 C atoms, except for one -CH group. ２ - One or more -CH groups, if present. ２ The - group may be replaced with -O- or -(C=O)-, but two adjacent -CH groups may be replaced. ２ - A - group cannot be replaced with -O-; one or multiple -CH groups if present. ２ The - group may be replaced with -CH=CH- or -C≡C-, where one or more H atoms are replaced with F, OR １３ , N(R １３ ) (Caution １４ ) or R １５ It can be replaced with, R １２ Each of these is an alkyl group having one H atom and 1 to 20 C atoms independently of each other (except for one -CH group). ２ - group or multiple -CH groups ２ The - group may be replaced with -O- or -(C=O)-, but two adjacent -CH groups may be replaced. ２ - The - group cannot be replaced with -O-. ), a hydrocarbon group containing a cycloalkyl or alkylcycloalkyl unit (however, one -CH ２ - group or multiple -CH groups ２ The - group may be replaced with -O- or -(C=O)-, but two adjacent -CH groups may be replaced. ２ - Groups cannot be replaced with -O-, except that one or more H atoms can be replaced with F, OR １３ , N(R １３ ) (Caution １４ ) or R １５ ) or aromatic or heteroaromatic hydrocarbon groups (where one H atom or multiple H atoms are OR １３ , N(R １３ ) (Caution １４ ) or R １５ It can be replaced with this.) R １３ and R １４ Each of these 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 of these represents an alkyl group having 1 to 10 C atoms independently of each other, except for one -CH group. ２ - group or multiple -CH groups ２ The - group may be replaced with -O- or -(C=O)-, but two adjacent -CH groups may be replaced. ２ -It is not possible to replace the - group with -O-. R １６ Each of these independently comprises an H atom, an alkyl or alkoxy group having 1 to 10 C atoms, an O-cycloalkyl group having 3 to 12 C atoms, and O ・ or OH, S １１ and S １２ Each alkylene group has 1 to 20 carbon atoms independently of each other (except for one -CH group). ２ - One or more -CH groups, if present. ２ The - group may be replaced with -O- or -(C=O)-, but two adjacent -CH groups may be replaced. ２ - Groups cannot be replaced with -O-, except that one or more H atoms may be F, OR １３ , N(R １３ ) (Caution １４ ) or R １５ It can be replaced with ). ) represents or represents a single bond, Y １１ ~Y １４ Each of these independently represents either methyl or ethyl. X １１ This represents C, Z １１ to Z １４ are each independently of the others —O—, —(C═O)—, —O—(C═O)—, —(C═O)—O—, —O—(C═O)—O—, —(N—R １３ ), —N—R １３ —(C═O)— or a single bond, and when S １１ is a single bond, Z １１ and Z １２ do not both represent —O— at the same time; when S １２ is a single bond, Z １３ and Z １４ do not both represent —O— at the same time; when q represents 0, Z １２ and Z １３ do not both represent —O— at the same time, p represents 1 or 2, q represents 0 or 1, o represents (3-p), n represents an integer from 1 to 10. m represents an integer from 0 to 8, however n × p represents an integer from 1 to 10, and 【Chemistry 4】 This represents an organic substructure having (m + n) bonding sites.

2. In equation I, k represents 1, l represents 0, and A ０ teeth, 【Transformation 5】 The medium according to claim 1, characterized in that it represents [the specified value].

3. 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 6】 【Transformation 7】 (In the formula, R １ and R ２ This is as defined in claim 1, L １ ~L ６ Each of these independently represents an alkyl group having an H atom, F, Cl, or 1 to 4 C atoms.

4. The medium according to claim 1, characterized in that one or more compounds of formula H are selected from the group consisting of compounds of the following formulas. 【Transformation 8】 【Chemistry 9】 【Chemistry 10】 (In the formula, R １１ represents, independently of one another, a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, provided that one -CH ２ - group or, if present, a plurality of -CH ２ - groups may be replaced by -O- or -(C=O)-, provided that two adjacent -CH ２ - groups cannot be replaced by -O-, and one or, if present, a plurality of -CH ２ - groups may be replaced by -CH=CH- or -C≡C-, provided that one hydrogen atom or a plurality of hydrogen atoms may be replaced by F, OR １３ , N(R １３ )(R １４ ) or R １５ ; R １６ is an H atom or O ・ This represents, n represents an integer from 0 to 12, and S １１ and S １２ Each alkylene group has 1 to 20 carbon atoms independently of each other (except for one -CH group). ２ - One or more -CH groups, if present. ２ The - group may be replaced with -O- or -(C=O)-, but two adjacent -CH groups may be replaced. ２ - Groups cannot be replaced with -O-, except that one or more H atoms may be F, OR １３ , N(R １３ ) (Caution １４ ) or R １５ It can be replaced with ). ) It represents either a simple conjunction or a single link. )

5. The liquid crystal medium according to claim 1, characterized by containing one or more compounds selected from the following formulas. 【Chemistry 11】 【Chemistry 12】 【Chemistry 13】 【Chemistry 14】

6. The liquid crystal medium according to claim 1, characterized by containing one or more compounds selected from the following formulas. 【Chemistry 15】 【Chemistry 16】 (In the formula, "alkyl" and "alkyl ＊ " is C １～６ - Represents alkyl, "alkenyl" and "alkenyl" ＊ " are each independent of each other C ２～６ - Represents Alkenil, X ０ F, Cl, CN, SF ５ , SCN, NCS, halogenated alkyl group having up to 6 C atoms, halogenated alkenyl group, halogenated alkoxy group or halogenated alkenyloxy group, L represents H or F, and R is C １～６ - Alkyl, C １～６ - Alkoxy or C ２～６ (—Represents Alkenil.)

7. The liquid crystal medium according to claim 1, characterized by containing one or more compounds selected from the group consisting of the following formulas. 【Chemistry 17】 (In the formula, each base is identical or different in each instance and has the following meanings independently of each other: [Chemistry 18] 【Chemistry 19】 【Chemistry 20】 R １ , R ２ In claim 1, R １ and R ２ It is one of the meanings that can be given to it. R ３ R １ One of the meanings given to X １ And, X １ This is a fluorinated alkyl or alkoxy having one, two, or three C atoms. Z ｘ Z ｙ is, -CH ２ CH ２ -, -CH=CH-, -CF ２ O-, -OCF ２ -ien-CH ２ O-, -OCH ２ -, -CO-O-, -O-CO-, -C ２ F ４ -, -CF=CF-, -CH=CH-CH ２ O- or single bond, Z ｚ CH ２ O or single bond, Y １ is either O or S, L １～４ is H, F, or Cl, x and y are 0, 1, or 2, where x + y is 3 or less. z is either 0 or 1, However, in formula B, the dibenzofuran or dibenzothiophene group may be further substituted with a methyl or methoxy group. However, the compound of formula Y has at least one substituent L which is F or Cl. １～４ (Includes.)

8. The liquid crystal medium according to claim 1, characterized by containing one or more compounds selected from the group consisting of the following formulas. 【Chemistry 21】 (In the formula, each base has the following meanings, independently of the others, in each instance being identical or different: 【Chemistry 22】 R ０ In claim 1, R １ It is one of the meanings that can be given to it. X ０ F, Cl, CN, SF ５ , SCN, NCS, halogenated alkyl group having up to 6 C atoms, halogenated alkenyl group, halogenated alkoxy group or halogenated alkenyloxy group, Y １～６ is H or F, Y ０ is H or CH ３ (That is the case.)

9. The liquid crystal medium according to claim 8, wherein one or more compounds of formula II are selected from the following sub-formulas. 【Chemistry 23】 【Chemistry 24】 (In the formula, R ０ and X ０ (This has the meaning given by equation II.)

10. The liquid crystal medium according to claim 8, wherein one or more compounds of formula III are selected from the following sub-formulas. 【Chemistry 25】 【Chemistry 26】 【Chemistry 27】 【Chemistry 28】 (In the formula, R ０ and X ０ (This has the meaning given by equation III.)

11. The liquid crystal medium according to claim 1, characterized in that it further contains one or more compounds selected from the group consisting of the following formulas. 【Chemistry 29】 (In the formula, R0 is one of the meanings given to R1 in claim 1, X0 is F, Cl, CN, SF5, SCN, NCS, a halogenated alkyl group having up to six carbon atoms, a halogenated alkenyl group, a halogenated alkoxy group, or a halogenated alkenyloxy group. Y1-4 are either H or F. Y5 is H or CH3, Z ０ is, -C ２ H ４ -, - (CH ２ ) ４ -, -CH=CH-, -CF=CF-, -C ２ F ４ -Eno--CH ２ CF ２ -, -CF ２ CH ２ -ien-CH ２ O-, -OCH ２ -, -COO- or -OCF ２ - Also, in formulas V and VI, single bonds are also -CF, and in formulas V and VIII, -CF ２ It also represents O-, r represents 0 or 1, and s represents either 0 or 1.

12. The liquid crystal medium according to claim 1, characterized by containing one or more compounds of formula XIV. 【Transformation 30】 (In the formula, R １ and R ２ Each of these terms independently represents an n-alkyl, alkoxy, oxaalkyl, fluoroalkyl, or alkenyl molecule, each having up to six carbon atoms.

13. The liquid crystal medium according to claim 1, characterized by containing one or more compounds of formula XVI. 【Chemistry 31】 (In the formula, R1 and R2 are one of the meanings given to R1 and R2 in claim 1, L1 is H, F, or Cl.

14. The liquid crystal medium according to claim 1, characterized by containing one or more compounds selected from the group consisting of the following formulas. 【Chemistry 32】 (In the formula, R1 and R2 are one of the meanings given to R1 and R2 in claim 1, L1 is H, F, or Cl.

15. The liquid crystal medium according to claim 1, characterized by containing one or more compounds selected from the group consisting of the following formulas. 【Transformation 33】 【Transformation 34】 (In the formula, R0 is one of the meanings given to R1 in claim 1, X0 is F, Cl, CN, SF5, SCN, NCS, a halogenated alkyl group having up to six carbon atoms, a halogenated alkenyl group, a halogenated alkoxy group, or a halogenated alkenyloxy group. Y1-4 are either H or F. Y5 is either H or CH3.

16. The liquid crystal medium according to claim 1, characterized by containing one or more compounds selected from the group consisting of the following formulas. 【Chemistry 35】 (In the formula, 【Transformation 36】 R1 is one of the meanings given to R1 in claim 1, X0 is F, Cl, CN, SF5, SCN, NCS, a halogenated alkyl group having up to six carbon atoms, a halogenated alkenyl group, a halogenated alkoxy group, or a halogenated alkenyloxy group.

17. The liquid crystal medium according to claim 1, characterized by containing one or more compounds selected from the group consisting of the following formulas. 【Chemistry 37】 (In the formula, R1 and R2 are one of the meanings given to R1 and R2 in claim 1, L1 is H, F, or Cl.

18. A liquid crystal medium according to any one of claims 1 to 17, characterized by comprising compounds of formulas I and H, and one or more compounds selected from the group consisting of formulas Z1, Z2, Z3, Z4, Z5, Y, B, II, III, IV, VI, XIV, XX, XII, XXIII, XXIX, XVI, XVIIa, XVIIb, XVIIc, XXXII, and XXXIV.

19. The liquid crystal medium according to claim 1, characterized in that it contains one or more polymerizable compounds.

20. A method for preparing a liquid crystal medium according to claim 1, characterized in that two or more compounds of formula I and one or more compounds of formula H are mixed with one or more mesogenic compounds and optionally one or more polymerizable compounds and / or one or more additives.

21. Use of the liquid crystal medium according to claim 1 for electro-optical purposes.

22. An electro-optical liquid crystal display comprising the liquid crystal medium described in claim 1.

23. The electro-optical liquid crystal display according to claim 22, 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.

24. The electro-optical liquid crystal display according to claim 22, characterized in that it is an FFS, HB-FFS, XB-FFS, PS-HB-FFS, PS-XB-FFS, IPS, or PS-IPS display.

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