Liquid crystal medium

Abstract

The present invention relates to dichroic dye compounds of formula I, as defined in claim 1, which are based on the donor-acceptor structure wherein the donor moiety comprises a polycyclic heteroaromatic group consisting of at least four fused rings, to mesogenic media comprising one or more compounds of formula I, the present invention relates to novel compounds, mesogenic media and liquid crystal materials, and to the use of these compounds, mesogenic media and liquid crystal materials in optical, electronic and electro-optical applications, in particular in devices for regulating energy through external spaces into internal spaces, for example in switchable windows for solar control in smart buildings and vehicles, with energy conservation and improved comfort.

Description

Technical Field

[0001] This invention relates to dichroic dye compounds of Formula I as defined below, based on a donor-acceptor structure, wherein the donor portion comprises a polycyclic heteroaromatic group consisting of at least four fused rings, to mesocrystalline media comprising one or more compounds of Formula I, and to the use of these compounds and mesocrystalline media in optical, electronic, and electro-optical applications, particularly in devices for regulating the flow of energy through external space into internal space, such as in switchable windows for solar control in smart buildings and vehicles, which offer energy savings and improved comfort. Background Technology

[0002] The review article "Properties, requirements and possibilities of smart windows for dynamic daylight and solar energy control in buildings: A state-of-the-art review" by R. Baetens et al., Solar Energy Materials & Solar Cells 94 (2010), pp. 87-105, describes color-tunable smart windows. Smart windows can utilize various technologies for adjusting light transmittance, such as electrochromic devices, liquid crystal devices, and electrophoretic or suspended particle devices. Liquid crystal-based devices work by applying an electric field to change the orientation of liquid crystal molecules between two conductive electrodes, thereby altering their transmittance.

[0003] Liquid crystal materials, particularly those used as dielectrics in display devices, have optical properties that can be affected by an applied voltage. Electro-optic devices based on liquid crystals are well known in the art and can be based on a variety of effects. Such devices include, for example, cells with dynamic scattering, DAP (Difference-Adjustment Phase-Deformation) cells, TN cells with a twisted nematic structure, STN ("Super Twisted Nematic") cells, SBE ("Super Birefringence Effect") cells, OMI ("Optical Mode Interference") cells, and guest-subject cells.

[0004] The guest-host effect-based device was first described by Heilmeier and Zaoni (GH Heilmeier et al., Appl. Phys. Lett., 1968, 13, 91f.) and has since been widely used, primarily in liquid crystal (LC) display elements. In the guest-host system, in addition to the liquid crystal, the LC medium contains one or more dichroic dyes. Due to the direction-dependent absorption of the dye molecules, the transmittance of the dye-doped liquid crystal can be adjusted by changing the orientation of the dye along with the liquid crystal.

[0005] In addition to their use in LC displays, this type of device is also used as a switching element for regulating the passage of light or energy, as described in, for example, WO 2009 / 141295 and WO 2010 / 118422.

[0006] Many different technical solutions have been proposed for devices used to regulate the flow of energy from the external space into the internal space.

[0007] In some devices, transmittance can be reversibly altered, whereby the intensity of incident light can be reduced, weakened, or colored. Such devices can therefore operate and switch between bright and dark states (i.e., relatively high transmittance and relatively low transmittance states).

[0008] In one possible configuration of the device, a combination of a liquid crystal medium and one or more dichroic dyes as described above can be used in the switching layer. By applying a voltage, a change in the orientation of the dichroic dye molecules can be achieved in such a switching layer. Due to orientation-dependent absorption, a change in the transmittance of this switching layer can thus be obtained. A corresponding device is described, for example, in WO 2009 / 141295.

[0009] Alternatively, such a change in transmission behavior can also be achieved in the absence of voltage by temperature-induced transition from the isotropic state of the liquid crystal medium to the liquid crystal state, as described, for example, in US 2010 / 0259698.

[0010] WO 2009 / 141295 and WO 2010 / 118422 describe liquid crystal media for object-subject type optical devices comprising cyanobiphenyl derivatives and one or more dichroic dyes. Rylene dyes have been described for use in the aforementioned devices, for example in WO 2009 / 141295, WO 2013 / 004677 and WO 2014 / 090373. The use of benzothiadiazole in the aforementioned devices is described in WO 2014 / 187529 and WO 2020 / 104563, and the use of thiadiazoquinoxaline in the aforementioned devices is described in WO 2016 / 177449 ​​and WO 2020 / 104563.

[0011] There remains a need in the art for dichroic dye compounds and media containing such compounds, which provide benefits in terms of device performance and reliability. Summary of the Invention

[0012] Therefore, the object of the present invention is to provide improved dye compounds that are particularly suitable for guest-host type applications and can advantageously contribute to the effective and efficient performance of switchable devices.

[0013] Another objective is to provide an improved mesocrystalline medium that contains these compounds and exhibits a wide and stable range of LC phases and particularly favorable low-temperature stability, and which in turn produces a suitable high degree of order.

[0014] Another objective is to provide a stable and reliable switching medium for electro-optical applications, which allows for particularly beneficial performance in devices used to regulate the flow of energy from the external space into the internal space, especially in smart switchable windows, such as in terms of stability and contrast or aesthetic impression relative to direct and prolonged sunlight. Other objectives of the invention will be apparent to those skilled in the art from the following detailed description.

[0015] The above objectives are achieved by the subject matter defined in the independent claims, while preferred embodiments are set forth in the corresponding dependent claims and are further described below.

[0016] The present invention specifically provides the following items, including key aspects, preferred embodiments and specific features, each of which, individually and in combination, contribute to achieving the above objectives and ultimately provide additional advantages.

[0017] The first aspect of the present invention provides a compound of formula I:

[0018]

[0019] in

[0020] R 1 and R 2 H, F, CN, N(R) may be represented in the same or different ways. z 2. A straight-chain alkyl group having 1 to 20 carbon atoms or a branched or cyclic alkyl group having 3 to 20 carbon atoms, wherein, in addition, one or more non-adjacent CH2 groups may be independently separated from each other by -C(R) z )=C(R z )-、-C≡C-、 , , , , -N(R) z -, -O-, -S-, -CO-, -CO-O-, -O-CO-, or -O-CO-O- are substituted in such a way that the O and / or S atoms are not directly connected to each other, and in addition, one or more H atoms may be substituted by F, Cl, Br, I, or CN.

[0021] R zEach occurrence may represent, in the same or different ways, H, halogen, straight-chain alkyl group having 1 to 12 carbon atoms, or branched or cyclic alkyl group having 3 to 12 carbon atoms, wherein, in addition, one or more non-adjacent CH2 groups may be replaced by -O-, -S-, -CO-, -CO-O-, -O-CO-, or -O-CO-O- in such a way that the O and / or S atoms are not directly connected to each other, and wherein, in addition, one or more H atoms may be replaced by F or Cl.

[0022] Q 1 and Q 2 The same or different representations of single bonds, -O-, -S-, -CF2O-, -OCF2-, -CF2-, -CF2CF2-, -CO-, -CR x1 =CR x2 -、-C≡C-、-NR x1 -, -N=N- or alicyclic or heterocyclic groups, preferably having 4 to 25 ring atoms, may also contain fused rings, and are either unsubstituted or mono- or polysubstituted with L.

[0023] Z 1 and Z 2 The same or different representations of single bonds, -O-, -S-, -C(O)-, -CR y1 R y2 -, -CF2O-, -OCF2-, -C(O)-O-, -OC(O)-, -OC(O)-O-, -OCH2-, -CH2O-, -SCH2-, -CH2S-, -CF2S-, -SCF2-, -(CH2) n1 -, -CF2CH2-, -CH2CF2-, -(CF2) n1 -、-CR x1 =CR x2 -、-C≡C-、-CR x1 =CR x2 -CO-, -CO-CR x1 =CR x2 -、-CR x1 =CR x2 -COO-、-OCO-CR x1 =CR x2 -or -N=N-,

[0024] R x1 R x2 Each can independently represent H, F, Cl, CN, or an alkyl group having 1 to 12 carbon atoms.

[0025] R y1 It represents H or an alkyl group having 1 to 12 carbon atoms.

[0026] Ry2 Indicates an alkyl group having 1 to 12 carbon atoms.

[0027] n1 represents 1, 2, 3, or 4.

[0028] A 1 and A 2 The same or different groups may represent aromatic, heteroaromatic, alicyclic, or heterocyclic groups, preferably having 4 to 25 ring atoms, and may also contain fused rings, and may be unsubstituted or monosubstituted or polysubstituted.

[0029] L represents F, Cl, -CN, or a straight-chain alkyl group having 1 to 25 carbon atoms, or a branched or cyclic alkyl group having 3 to 25 carbon atoms, wherein one or more non-adjacent CH2- groups are optionally replaced by -O-, -S-, -CO-, -CO-O-, -O-CO-, or -O-CO-O- in such a way that the O atoms and / or S atoms are not directly connected to each other, and wherein one or more H atoms are each optionally replaced by F or Cl.

[0030] D represents the donor, preferably an electron-rich conjugated moiety, selected from heteroaromatic groups comprising at least four fused rings, preferably at least four linear fused rings, wherein each ring may be unsubstituted or monosubstituted or polysubstituted by L.

[0031] A represents the acceptor group, preferably an electron-deficient moiety.

[0032] n represents 0, 1, 2, or 3, preferably 0, 1, or 2, and

[0033] o represents 0 or 1.

[0034] The compound contains at least five rings (including fused rings).

[0035] The term "ring" as used herein refers to a cyclic group having a closed ring structure, i.e., a closed ring of atoms. The term "ring" in this document also includes cyclic, condensed, or fused rings, particularly edge-to-edge fused rings, where the rings are fused if they share two or more atoms. In this respect, compounds (especially polycyclic compounds) are considered to contain a number of rings equal to the number of breaks required to convert them into open-chain compounds.

[0036] In this paper, the combination of donor D adjacent to acceptor A preferably forms a π-conjugated system. The donor group D contains or preferably consists of an unsubstituted or substituted heteroaromatic group, particularly a polycyclic heteroaromatic group including a fused ring, preferably an unsubstituted or substituted heterobenzobenzene, more preferably an unsubstituted or substituted S,N-hexabenzobenzene having extended π-conjugation.

[0037] The acceptor group A is preferably an electron-withdrawing group, and more preferably an electron-deficient part that is lacking π electrons.

[0038] If present, then group Z is directly adjacent to groups D and A. 1 and Z 2 Preferably, it is a single bond or a π-conjugated group.

[0039] It has been surprisingly found that compounds of Formula I, as described herein, exhibit excellent combined properties and characteristics, such as in terms of extinction coefficient, stability, and solubility, which can produce beneficial properties in optical, electro-optical, and electronic applications, and particularly in guest-subject applications (such as in dimmable smart windows). In particular, compounds according to the invention exhibit excellent solubility and stability in liquid crystal media.

[0040] In particular, it has been surprisingly found that the compound of formula I exhibits favorable solubility in liquid crystal media while simultaneously producing suitable light and temperature stability. Furthermore, this compound, as a mixture, demonstrates favorable compatibility and stability, possesses high color purity, and thus offers the possibility of providing media with a neutral or grayish appearance as needed. Simultaneously, this compound can produce only weak or even no discernible fluorescence.

[0041] Compounds of Formula I have been found to advantageously exhibit large extinction coefficients in the VIS and / or NIR regions of light, while also possessing a suitably high dichroic ratio. This combination of properties is now recognized as advantageously contributing to efficient and effective device performance. The high extinction coefficient, in particular, coupled with the high dichroic ratio, can be advantageous in that lower dye concentrations can be used and / or a single switching layer can be sufficient and / or a smaller switching layer thickness or cell gap is sufficient to obtain the desired contrast and effective dark state. Lower dye concentrations also have advantages in terms of solubility and viscosity considerations.

[0042] Compounds of Formula I are therefore particularly suitable for guest-host type applications, in which dye-doped mesocrystalline media can exhibit a suitably broad and stable LC phase range and, in particular, advantageous low-temperature stability. The mesocrystalline media according to the invention can thus provide benefits in terms of device performance and reliability, especially in smart switchable windows.

[0043] It was also found that the compound not only exhibits favorable solubility in the LC medium itself, but also mixes well with other dichroic dye compounds in the medium. This advantageously contributes to improving the ability to provide custom dye-doped liquid crystal media, particularly in producing specific colors or even covering the entire VIS range to achieve a black appearance. In this regard, compound I can be selected and tuned to produce the desired color while exhibiting only very weak or even no fluorescence.

[0044] Therefore, in another aspect, compositions, particularly mixtures, are provided that contain two or more compounds, preferably three or more compounds, more preferably four or more compounds according to the invention.

[0045] As described herein, the compounds according to the invention can be advantageously used in liquid crystal media.

[0046] Therefore, another aspect relates to a liquid crystal medium that, in addition to at least one mesocrystalline compound, further comprises one or more compounds according to the invention. Preferably, the liquid crystal medium contains two or more compounds of formula I or corresponding preferred formulas, more preferably three or more compounds of formula I or corresponding preferred formulas.

[0047] It has been found that the liquid crystal medium according to the invention can produce a stable, reliable, and highly efficient switching medium for electro-optical applications, which allows particularly advantageous performance in devices for regulating the flow of energy through external space into internal space, especially in smart switchable windows. In this respect, the high extinction coefficient and favorable dichroism ratio of the compound of formula I in the medium can contribute to the beneficial performance in object-subject applications such as dimmable smart windows.

[0048] Therefore, according to another aspect of the invention, a device for regulating the flow of energy through an external space into an internal space is provided, wherein the device comprises a switching layer containing a liquid crystal medium as described herein according to the invention. In particular, the device may be contained within a window.

[0049] In another aspect of the invention, the compounds and mesocrystalline media according to the invention are used in electro-optic displays, devices for regulating energy to pass through external space into internal space, electronic semiconductors, organic field-effect transistors, printed circuits, radio frequency identification elements, diodes, organic light-emitting diodes, lighting elements, photovoltaic devices (especially as photosensitizers or semiconductors therein), optical sensors, effect pigments, decorative elements, or as dyes for coloring polymers, for example in the automotive field.

[0050] In another aspect, a window is provided that includes means for regulating energy passing through the external space into the internal space, wherein the means contains a switching layer comprising a liquid crystal medium according to the invention.

[0051] The liquid crystal windows according to the invention can be used in sustainable glass applications in buildings and vehicles, particularly by generating energy savings relative to lighting, cooling and / or heating and by positively impacting the life cycle (e.g., in terms of maintenance), while also providing improved thermal and visual comfort.

[0052] In another aspect of the invention, a method for preparing compounds of formula I is provided. In particular, this method provides a simple and readily available way to obtain compounds according to the invention.

[0053] Without limiting the scope of the invention, the invention is set forth below by a detailed description of aspects, embodiments and specific features, and the specific embodiments are described in more detail.

[0054] In this invention, the device for regulating the flow of energy through the external space into the internal space preferably refers to a device for regulating energy (especially light, and particularly sunlight) through a region arranged within a structure with relatively low energy transmittance. The structure with low energy transmittance can be a wall. Therefore, the energy can, for example, pass through open areas or, particularly, glass areas within the wall. Thus, the device is preferably arranged as part of a window (e.g., an insulated glass unit).

[0055] The passage of regulated energy is from the external space (preferably an environment exposed to direct or indirect sunlight) into the internal space (e.g., a building or vehicle, or another unit substantially isolated from that environment).

[0056] For the purposes of this invention, the term "energy" refers specifically to energy generated by electromagnetic radiation in the UV-A, VIS, and NIR regions. In particular, it refers to energy generated by radiation that is not absorbed or is absorbed only to a negligible degree by materials commonly used in windows (e.g., glass). Hereinafter, the UV-A region refers to wavelengths in the range of 320 to 380 nm, the VIS region refers to wavelengths in the range of 380 to 780 nm, and the NIR region refers to wavelengths in the range of 780 to 2000 nm. Accordingly, the term "light" generally refers to electromagnetic radiation having wavelengths between 320 and 2000 nm, and particularly between 380 and 780 nm.

[0057] In this document, dichroic dyes refer to light-absorbing compounds, where the absorption properties depend on the orientation of the compound relative to the polarization direction of light. The dichroic dye compounds according to the invention typically have an elongated shape, meaning that the compound is significantly longer in one spatial direction (i.e., along the longitudinal axis) than in the other two spatial directions.

[0058] The term "organic group" refers to a carbon-based or hydrocarbon-based group.

[0059] The term "carbogroup" refers to a monovalent or polyvalent organic group containing at least one carbon atom, wherein the group does not contain other atoms, such as, for example, -C≡C-, or optionally contains one or more other atoms, such as, for example, N, O, S, P, Si, Se, As, Te, or Ge, such as a carbonyl group. The term "hydrocarbon group" refers to a carbogroup that additionally contains one or more H atoms and optionally one or more heteroatoms, such as, for example, N, O, S, P, Si, Se, As, Te, or Ge.

[0060] "Halogen" refers to F, Cl, Br or I, preferably F or Cl.

[0061] The carbonyl or hydrocarbon group can be a saturated or unsaturated group. Unsaturated groups are, for example, aryl, alkenyl, or alkynyl. The carbonyl or hydrocarbon group having three or more atoms can be straight-chain, branched, and / or cyclic, and may also contain spirocyclic linkages or fused rings.

[0062] The terms "alkyl", "aryl", and "heteroaryl" also include polyvalent groups, such as alkylene, arylene, and heteroarylene.

[0063] The term "aryl" refers to an aromatic carbonyl group or a group derived therefrom. The term "heteroaryl" refers to an "aryl" group as defined above, which contains one or more heteroatoms.

[0064] Preferred carbonyl and hydrocarbon groups are alkyl, alkenyl, alkynyl, alkoxy, alkyl carbonyl, alkoxy carbonyl, alkyl carbonyl, and alkoxy carbonyloxy groups having 1 to 40, preferably 1 to 25, particularly preferably 1 to 18 C atoms, optionally substituted aryl or aryloxy groups having 6 to 40, preferably 6 to 25 C atoms, or alkylaryl, arylalkyl, alkylaryloxy, arylalkoxy, arylcarbonyl, aryloxy carbonyl, aryl carbonyloxy, and aryloxy carbonyloxy groups having 6 to 40, preferably 6 to 25 C atoms, optionally substituted alkylaryl, arylalkyl, alkylaryloxy, arylalkoxy, arylcarbonyl, aryloxy carbonyl, and aryloxy carbonyloxy groups.

[0065] Other preferred carbonyl and hydrocarbon groups are C1-C. 40 Alkyl, C2-C 40 alkenyl, C2-C 40 alkynyl group, C3-C 40 Allyl, C4-C 40 Alkyl diene group, C4-C 40 Polyene, C6-C 40 Aryl, C6-C 40 Alkyl aryl, C6-C 40 arylalkyl, C6-C 40 Alkyl aryloxy, C6-C 40 arylalkoxy, C2-C 40 heteroaryl, C4-C 40 cycloalkyl, C4-C40 Cycloalkenyl groups, etc. Particularly preferred are C1-C... 22 Alkyl, C2-C 22 alkenyl, C2-C 22 alkynyl group, C3-C 22 Allyl, C4-C 22 Alkyl diene group, C6-C 12 Aryl, C6-C 20 arylalkyl and C2-C 20 Mixed aromatic compounds.

[0066] Other preferred carbonyl and hydrocarbon groups are straight-chain, branched, or cyclic alkyl groups having 1 to 40, preferably 1 to 25 C atoms, which are unsubstituted or monosubstituted or polysubstituted with F, Cl, Br, I, or CN, and one or more of the non-adjacent CH2 groups can be independently converted to -C(R) z )=C(R z )-、-C≡C-、-N(R z -, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-, -O-CO-O- are replaced by O and / or S atoms not being directly connected to each other.

[0067] R z Preferably, it represents H, halogen, a straight-chain, branched, or cyclic alkyl chain having 1 to 25 C atoms, wherein, in addition, one or more non-adjacent C atoms may be replaced by -O-, -S-, -CO-, -CO-O-, -O-CO-, or -O-CO-O- and one or more H atoms may be replaced by fluorine, optionally substituted aryl or aryloxy groups having 6 to 40 C atoms, or optionally substituted heteroaryl or heteroaryloxy groups having 2 to 40 C atoms.

[0068] Preferred alkyl groups are, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, 2-methylbutyl, n-pentyl, sec-pentyl, cyclopentyl, n-hexyl, cyclohexyl, 2-ethylhexyl, n-heptyl, cycloheptyl, n-octyl, cyclooctyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, trifluoromethyl, perfluoron-butyl, 2,2,2-trifluoroethyl, perfluorooctyl, and perfluorohexyl.

[0069] Preferred alkenyl groups are, for example, vinyl, propenyl, butenyl, pentenyl, cyclopentenyl, hexenyl, cyclohexenyl, heptenyl, cycloheptenyl, octenyl, and cyclooctenyl.

[0070] Preferred alkynyl groups are, for example, ethynyl, propynyl, butynyl, pentynyl, hexynyl, and octyynyl.

[0071] Preferred alkoxy groups are, for example, methoxy, ethoxy, 2-methoxyethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, 2-methylbutoxy, n-pentoxy, n-hexoxy, n-heptoxy, n-octoxy, n-nonoxy, n-decoxy, n-undecoxy, and n-dodecoxy.

[0072] Preferred amino groups are, for example, dimethylamino, methylamino, methylphenylamino, and phenylamino.

[0073] Aryl and heteroaryl groups can be monocyclic or polycyclic, meaning they can contain one ring, such as a phenyl group, or two or more rings. They can also be fused, such as a naphthyl group, or covalently bonded, such as a biphenyl group, or contain a combination of fused and linking rings. Heteroaryl groups contain one or more heteroatoms, preferably selected from O, N, S, and Se. This type of ring system can also contain individual non-conjugated units, as in this case, for example, in the basic structure of fluorene.

[0074] Particularly preferred are monocyclic, bicyclic, or polycyclic aryl groups having 6 to 50 carbon atoms and monocyclic, bicyclic, or polycyclic heteroaryl groups having 2 to 50 carbon atoms, which optionally contain fused rings and are optionally substituted. Furthermore preferred are 5, 6, or 7-membered aryl and heteroaryl groups, wherein, additionally, one or more CH groups may be replaced by N, S, or O in such a manner that the O atoms and / or S atoms are not directly connected to each other.

[0075] Preferred aryl groups include those derived from the parent structure benzene, biphenyl, terphenyl, [1,1':3',1'']terphenyl, naphthalene, anthracene, binaphthalene, phenanthrene, pyrene, dihydropyrene, β-, perylene, tetraphenyl, pentaphenyl, benzo[a]pyrene, fluorene, indene, indo[a]fluorene, spirodifluorene, etc.

[0076] Preferred heteroaryl groups are, for example, 5-membered rings, such as pyrrole, pyrazole, imidazole, 1,2,3-triazole, 1,2,4-triazole, tetrazolium, furan, thiophene, selenophene, oxazole, isoxazole, 1,2-thiazole, 1,3-thiazole, 1,2,3-oxadiazole, 1,2,4-oxadiazole, 1,2,5-oxadiazole, 1,3,4-oxadiazole, 1,2,3-thiadiazole, 1,2, 4-Thiadiazole, 1,2,5-Thiadiazole, 1,3,4-Thiadiazole, a 6-membered ring such as pyridine, pyridazine, pyrimidine, pyrazine, 1,3,5-triazine, 1,2,4-triazine, 1,2,3-triazine, 1,2,4,5-tetraazine, 1,2,3,4-tetraazine, 1,2,3,5-tetraazine, or a fused group such as indole, isoindole, indazine, indazole, benzimidazole Benzotriazole, purine, naphtheneimidazole, phenanthreneimidazole, pyridiniumimidazole, pyraziniumimidazole, quinoxalineimidazole, benzoxazole, naphtheneimidazole, anthraxazole, phenanthreneimidazole, isoxazole, benzothiazole, benzofuran, isobenzofuran, dibenzofuran, quinoline, isoquinoline, pteridine, benzo-5,6-quinoline, benzo-6,7-quinoline, benzo-7,8-quinoline, benzoisoquinoline, acridine Phenothiazine, phenoxazine, benzopyridinium, benzopyrimidine, quinoxaline, phenazine, naphthidine, azacarbazole, benzocarbline, phenanthridine, phenanthroxaline, thieno[2,3b]thiophene, thieno[3,2b]thiophene, dithieno[3,4-b]-1,4-dioxin, isobenzothiophene, dibenzothiophene, benzothiadiazo[3,4-b]-1,4-dioxin, or combinations of such groups. The heteroaryl group may also be substituted with alkyl, alkoxy, thioalkyl, fluorine, fluoroalkyl, or other aryl or heteroaryl groups.

[0077] (Non-aromatic) alicyclic and heterocyclic groups include saturated rings, i.e., those containing only single bonds, and also partially unsaturated rings, i.e., those containing multiple bonds. Heterocyclic rings contain one or more heteroatoms, preferably selected from Si, O, N, S, and Se.

[0078] (Non-aromatic) alicyclic and heterocyclic groups may be monocyclic, i.e., containing only one ring, such as, for example, cyclohexane, or polycyclic, i.e., containing multiple rings, such as, for example, decahydronaphthalene or bicyclooctane. Saturated groups are particularly preferred. Furthermore, monocyclic, bicyclic, or tricyclic groups having 3 to 25 carbon atoms are preferred, optionally containing fused rings and optionally substituted. Also preferred are 5, 6, 7, or 8-membered carbon ring groups, wherein, in addition, one or more carbon atoms may be substituted with Si and / or one or more CH groups may be substituted with N and / or one or more non-adjacent CH2 groups may be substituted with -O- and / or -S-.

[0079] Preferred alicyclic and heterocyclic groups are, for example, 5-membered groups such as cyclopentane, tetrahydrofuran, tetrahydrothiofuran, pyrrolidine; 6-membered groups such as cyclohexane, silinane, cyclohexene, tetrahydropyran, tetrahydrothiopyran, 1,3-dioxane, 1,3-dithiaane, piperidine; 7-membered groups such as cycloheptane; and fused groups such as tetrahydronaphthalene, decahydronaphthalene, indane, bicyclo[1.1.1]pentane-1,3-diyl, bicyclo[2.2.2]octane-1,4-diyl, spiro[3.3]heptane-2,6-diyl, octahydro-4,7-methylbridged indane-2,5-diyl.

[0080] The aryl, heteroaryl, carboxyl, and hydrocarbon groups optionally have one or more substituents, preferably selected from the group consisting of: silyl, sulfonyl, sulfonyl, formyl, amino, imino, nitrile, mercapto, nitro, halogen, C 1-12 Alkyl, C 6-12 Aryl, C 1-12 Alkoxy, hydroxyl, or combinations of such groups.

[0081] Preferred substituents are, for example, groups that promote dissolution, such as alkyl or alkoxy groups, electron-withdrawing groups, such as fluorine, nitro, or nitrile groups, or groups that increase the glass transition temperature (T0) of the polymer. g Substituents, especially large groups, such as, for example, tert-butyl or optionally substituted aryl groups.

[0082] Preferred substituents are F, Cl, Br, I, -CN, -NO2, -NCO, -NCS, -OCN, -SCN, and -C(=O)N(R). z )2、-C(=O)Y 1 -C(=O)R z -N(R) z )2, where R z It has the meaning indicated above, and Y 1 The term represents a halogen, optionally substituted silyl group, or an aryl group having 6 to 40, preferably 6 to 20, carbon atoms, and a straight-chain or branched alkyl group, alkoxy group, alkyl carbonyl group, alkoxy carbonyl group, alkyl carbonyloxy group, or alkoxy carbonyloxy group having 1 to 25 carbon atoms, wherein one or more H atoms may optionally be replaced by F or Cl.

[0083] More preferred substituents are, for example, F, Cl, CN, NO2, CH3, C2H5, OCH3, OC2H5, COCH3, COC2H5, COOCH3, COOC2H5, CF3, OCF3, OCHF2, OC2F5, and phenyl groups.

[0084] In this document, the substituents representing L are, each time appearing the same or different, preferably F, Cl, CN, SCN, SF5 or straight or branched, and in each case are optionally fluorinated alkyl, alkoxy, alkyl carbonyl, alkoxy carbonyl, alkyl carbonyloxy or alkoxy carbonyloxy having 1 to 12 C atoms.

[0085] Preferably, L, each time it appears, represents F or a straight or branched chain having 1 to 7 C atoms, optionally fluorinated alkyl or alkoxy in each case.

[0086] "Substituted silane or aryl" preferably refers to substituted silane, -CN, R y1 -OR y1 -CO-R y1 -CO-OR y1 -O-CO-R y1 OR-O-CO-OR y1 Replace, where R y1 It has the meaning indicated above.

[0087] As described herein, the Formula I compound has a donor-acceptor combination in its molecular structure, which produces an extremely high extinction coefficient, particularly in the visible light region, while also exhibiting favorable compatibility for guest-host applications, especially with suitable solubility and stability in liquid crystal media.

[0088] According to the present invention, group D in Formula I represents a donor group selected from unsubstituted or substituted heteroaromatic groups, comprising at least four fused rings, preferably at least four linear fused rings, which provide an electron-rich conjugated moiety.

[0089] The donor group D is preferably a polycyclic group, particularly a tetracyclic, pentacyclic, hexacyclic, or heptacyclic group, which is a heterocyclic aromatic group, i.e., at least one ring contains at least one non-carbon atom, preferably an aromatic group containing sulfur, nitrogen, and / or oxygen. In particular, this polycyclic heteroaromatic group comprises at least four fused rings, each of which may be unsubstituted or substituted, containing, for example, a thiophene-pyrrole fused group.

[0090] In a preferred embodiment, group D is selected from groups comprising, and preferably consisting of, linear fused rings, preferably unsubstituted or substituted heterocyclic benzenes. Particularly preferably, group D contains heterocyclic thiophene and pyrrole rings, wherein group D preferably comprises, and particularly consists of, fused heterocyclic thiophene and pyrrole rings, preferably substituted pyrrole rings, especially so-called S,N-hexacyclic benzenes. Tetracyclic, pentacyclic, and hexacyclic systems are preferred, especially S,N-hexacyclic tetraphenylene, S,N-hexacyclic pentaphenylene, and S,N-hexacyclic hexaphenylene, wherein such systems can be symmetrical or asymmetrical.

[0091] The heterobenzenes described herein are benzobenzene compounds containing or preferably consisting of heteroatom-substituted aromatic groups. In this respect, the benzobenzenes described herein are polycyclic aromatic hydrocarbons composed of linearly arranged fused benzene rings.

[0092] Preferably, the donor group D is a heterocyclic benzene with a linear fused ring, wherein each ring may be unsubstituted or monosubstituted or polysubstituted with L, wherein L is defined as described in the context.

[0093] In one implementation scheme, Z 1 and Z 2 Each can independently represent a single bond, -CH=CH-, -CF=CF-, or -C≡C-. Particularly preferred, Z 1 and Z 2 Indicates a single key.

[0094] Group R in Formula I 1 and R 2 Preferably, the alkyl groups are independently represented, and are preferably methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, or branched alkyl groups having 3 to 12 carbon atoms. Preferably, they have methyl, ethyl, n-propyl, n-butyl, or n-pentyl groups bonded to ethyl, n-propyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, or n-decyl groups, such as 2-ethylhexyl, 2-ethylheptyl, 2-ethyloctyl, 2-ethylnonyl, 2-ethyldecyl, 3-ethylhexyl, 3-ethylheptyl, 3-ethyloctyl, 3-ethylnonyl, 3-ethyldecyl, etc.

[0095] In another embodiment, group R 1 and R 2 Each of the above can be independently represented as a straight-chain or branched alkyl group or a dialkylamino group having 1 to 12 carbon atoms per alkyl group.

[0096] In one embodiment, the compound of formula I is selected from the group consisting of compounds of formulas I-1 and I-2:

[0097]

[0098] Where R 1 R 2 A 1 Z 1 Z 2 D, A, n, and o have the meanings given for Equation I above, and wherein the number of rings in the compound is at least 5.

[0099] And preferably,

[0100] R 1 and R 2 H and N(R) can be represented in the same or different ways. z2. A straight-chain alkyl group having 1 to 12 carbon atoms or a branched or cyclic alkyl group having 3 to 18 carbon atoms, wherein, in addition, one or more non-adjacent CH2 groups may be independently coupled with -N(R) z -, -O-, -S-, -CO-, -CO-O-, -O-CO-, or -O-CO-O- are substituted in such a way that the O and / or S atoms are not directly connected to each other, and in addition, one or more H atoms may be substituted by F.

[0101] R z Each occurrence may represent H, a straight-chain alkyl group having 1 to 12 carbon atoms, or a branched or cyclic alkyl group having 3 to 12 carbon atoms, respectively. Additionally, one or more non-adjacent CH2 groups may be replaced by -O-, -S-, -CO-, -CO-O-, -O-CO-, or -O-CO-O- in such a manner that the O and / or S atoms are not directly connected to each other. Furthermore, one or more H atoms may be replaced by F.

[0102] Z 1 and Z 2 The same or different representations of single bonds, -O-, -S-, -C(O)-, -CF2O-, -OCF2-, -C(O)-O-, -OC(O)-, -OCH2-, -CH2O-, -C≡C-, or -N=N-,

[0103] A 1 Each occurrence may be identical or different, representing an aromatic, heteroaromatic, alicyclic, or heterocyclic group having 4 to 25 ring atoms. It may also contain a fused ring, and it may be unsubstituted or monosubstituted or polysubstituted.

[0104] L represents F, Cl, -CN, or a straight-chain alkyl group having 1 to 25 carbon atoms, or a branched or cyclic alkyl group having 3 to 25 carbon atoms, wherein one or more non-adjacent CH2- groups are optionally replaced by -O-, -S-, -CO-, -CO-O-, -O-CO-, or -O-CO-O- in such a way that the O atoms and / or S atoms are not directly connected to each other, and wherein one or more H atoms are each optionally replaced by F.

[0105] D indicates a heterophenyl group comprising at least four fused rings, preferably at least four fused rings, wherein each ring may be unsubstituted or monosubstituted or polysubstituted by L.

[0106] For formula I-2, if group A does not contain any rings, then group D contains at least 5 fused rings.

[0107] A represents the acceptor group, preferably an electron-deficient moiety.

[0108] n represents 1, 2, or 3, preferably 1 or 2, more preferably 1, and

[0109] o represents 0 or 1, with 0 being preferred.

[0110] In a preferred embodiment, in formulas I, I-1, and I-2, and for the purposes of their preferred formulations described herein, group D is selected from groups Da, Db, and Dc.

[0111]

[0112] Among them, Ar 1 Ar 2 Ar 3 Ar 4 Ar 5 and Ar 6 Indicates fused rings, and

[0113] Ar 1 Select independently from the following formula

[0114]

[0115] Ar 4 Select independently from the following formula

[0116]

[0117] Ar 2 Ar 3 Ar 5 Ar 6 Select independently from the following formula

[0118]

[0119] W 1 Is it S, O, or Se?

[0120] U 1 It is CR a R b SiR a R b GeR a R b or NR a , where R a and R b Defined independently as R 4 ,

[0121] Among them, groups or Not with another group or Adjacent,

[0122] R 4R5, R6, and R7, each time appearing, represent a halogen or a straight-chain alkyl or alkoxy group having 1 to 20 carbon atoms, or a branched alkyl or alkoxy group having 3 to 20 carbon atoms, wherein one or more H atoms may be replaced by F.

[0123] The asterisk (*) in the ring indicates a C atom shared by adjacent fused rings, and...

[0124] Ar group 1 and Ar 4 The asterisk (*) on the single bond indicates that groups Da, Db, and Dc are bonded to other groups in the compound.

[0125] In this invention, particularly for compounds of formula I, all atoms also include their isotopes. In particular, one or more hydrogen atoms (H) may be replaced by deuterium (D), which is particularly preferred in some embodiments; high deuteration makes it possible to analyze or simplify the compound, especially at low concentrations.

[0126] Particularly preferably, for compounds of formula I, I-1 and I-2 and for their preferred formulas described herein, group D is selected from the following formulas.

[0127]

[0128] Where R 4 Each occurrence may represent a halogen or a straight-chain alkyl or alkoxy group having 1 to 20 carbon atoms or a branched alkyl or alkoxy group having 3 to 20 carbon atoms, wherein one or more H atoms may be replaced by F.

[0129] According to the present invention, in the compound of formula I, the chromophore system in the molecular structure is composed of a combination of donor group D and acceptor group that are directly adjacent.

[0130] In this paper, the acceptor group A is an electron-deficient moiety that exhibits electron-withdrawing properties. Preferably, the acceptor group A is a group with π-electron deficiency.

[0131] It has been surprisingly found that certain combinations of donor D and acceptor, as described herein, can produce benefits in dye performance, particularly in terms of extinction coefficient and reliability.

[0132] In one embodiment, the acceptor group A (especially the electron-withdrawing group A) is preferably selected from carbonyl and carbonyl-containing groups, sulfonyl and sulfonyl-containing groups, cyano and cyano-containing groups, nitro and nitro-containing groups, haloalkyl and haloalkyl-containing groups, electron-deficient aryl and electron-deficient aryl groups, electron-deficient heteroaryl and electron-deficient heteroaryl groups, benzothiadiazolyl, quinoxalinyl, especially quinoxalinyl containing nitriles, thiadiazolylquinoxalinyl, ryl, peryl, benzotriazolyl, anthraquinone, thiazothiazolyl, bis(thiadiazolyl)phenylene, pyridinyl, and diketopyrrolopyrroleyl.

[0133] In a preferred embodiment, group A in formulas I, I-1, and I-2 and their preferred formulations described herein is selected from the following formulas.

[0134]

[0135]

[0136] in

[0137] R 8 R 9 R 10 R 11 R 12 R 13 and R 14 Each occurrence may represent, in the same or different ways, H, halogen, CN, or a straight-chain alkyl group having 1 to 20 carbon atoms or a branched alkyl group having 3 to 20 carbon atoms, wherein one or more H atoms may be replaced by F.

[0138] R 15 The terms indicate halogen, CN, or a straight-chain alkyl group having 1 to 20 carbon atoms or a branched alkyl group having 3 to 20 carbon atoms.

[0139] The dashed lines indicate the remaining bonds of the compound.

[0140] In one embodiment, group A in formula I and its preferred formula 1Each occurrence is selected from alicyclic groups, heterocyclic groups, aryl groups, and heteroaryl groups, either identically or differently, and may be substituted by one or more L groups as defined herein, preferably 1,4-cyclohexene, wherein one or both non-adjacent CH2 groups may be substituted by O, 1,4-cyclohexenyl, 1,4-phenylene, 1,4-naphthylene, 2,6-naphthylene, thiazolyl-2,5-diyl, thiophene-2,5-diyl, thieno-2,5-diyl, selenophene-2,5-diyl, thieno-2,5-diyl, dithieno-2,5-diyl, dithieno-2,5-diyl, dithieno-2,5-diyl, cyclopentan-2,5-diyl, pyridine-2,5-diyl, pyrimidine The compounds are pyridinyl and pyridazinyl, wherein one or more H atoms may be replaced by a group L as defined herein, more preferably selected from 1,4-phenylene, 1,4-naphthylene, 2,6-naphthylene, thiazolyl-2,5-diyl, thiophene-2,5-diyl, thienothiophene-2,5-diyl, selenophene-2,5-diyl, thienopyrrole-2,5-diyl, dithienopyrrole, dithienosylsilanecyclopentadiene, cyclopentanoiddithienodiyl, pyridine-2,5-diyl, pyrimidinediyl, and pyridazinyl, wherein one or more H atoms may be replaced by a group L as defined herein, and particularly 1,4-phenylene, wherein one or more H atoms may be replaced by a group L as defined herein, wherein L is preferably F.

[0141] In a preferred embodiment, the compound of formula I is selected from the compound of formula IA.

[0142]

[0143] The compound contains at least 5 rings.

[0144] and

[0145] R 1 Represents H, N(R) z 2. A straight-chain alkyl group having 1 to 12 carbon atoms or a branched or cyclic alkyl group having 3 to 18 carbon atoms, wherein, in addition, one or more non-adjacent CH2 groups may be independently coupled with -N(R) z -, -O-, -S-, -CO-, -CO-O-, -O-CO-, or -O-CO-O- are substituted in such a way that the O and / or S atoms are not directly connected to each other, and in addition, one or more H atoms may be substituted by F.

[0146] Preferred representation of H, N(R) z 2. A straight-chain alkyl group having 1 to 12 carbon atoms or a branched or cyclic alkyl group having 3 to 18 carbon atoms, wherein, in addition, one or more non-adjacent CH2 groups may be independently substituted with -O-, wherein R is preferred. zEach occurrence may refer to H, a straight-chain alkyl group having 1 to 12 carbon atoms, or a branched or cyclic alkyl group having 3 to 12 carbon atoms.

[0147] R z Each occurrence may represent H, a straight-chain alkyl group having 1 to 12 carbon atoms, or a branched or cyclic alkyl group having 3 to 12 carbon atoms, respectively. Additionally, one or more non-adjacent CH2 groups may be replaced by -O-, -S-, -CO-, -CO-O-, -O-CO-, or -O-CO-O- in such a manner that the O and / or S atoms are not directly connected to each other. Furthermore, one or more H atoms may be replaced by F.

[0148] Z 1 This indicates a single bond, -CF2O-, -OCF2-, -C(O)-O-, -OC(O)-, -OCH2-, -CH2O-, -C≡C-, or -N=N-.

[0149] Preferred to represent a single bond,

[0150] A 1 Each occurrence may represent 1,4-cyclohexene, with one or both non-adjacent CH2 groups potentially replaced by O. The substitutions include 1,4-cyclohexeneyl, 1,4-phenylene, 1,4-naphthylene, 2,6-naphthylene, thiazolyl-2,5-diyl, thiophene-2,5-diyl, thienothiophene-2,5-diyl, selenophene-2,5-diyl, thienopyrrole-2,5-diyl, dithienopyrrolediyl, dithienosilylopyrocyclopentadienyl, cyclopentanopyrophenediyl, pyridine-2,5-diyl, pyrimidinediyl, or pyridazinediyl. One or more H atoms may be replaced by the L group.

[0151] L represents F, Cl, -CN, or a straight-chain alkyl group having 1 to 25 carbon atoms, or a branched or cyclic alkyl group having 3 to 25 carbon atoms, wherein one or more non-adjacent CH2- groups are optionally replaced by -O-, -S-, -CO-, -CO-O-, -O-CO-, or -O-CO-O- in such a way that the O atoms and / or S atoms are not directly connected to each other, and wherein one or more H atoms are each optionally replaced by F.

[0152] D represents a heteroaromatic group comprising at least four fused rings, preferably consisting of at least four fused rings, wherein each ring may be unsubstituted or monosubstituted or polysubstituted by L.

[0153] Preferably, if n is 0, then the group D contains at least 5 fused rings.

[0154] A represents the acceptor group, preferably an electron-deficient moiety, and

[0155] n represents 0, 1, or 2, preferably 0 or 1.

[0156] Particularly preferably, the compound of formula I is selected from the group consisting of:

[0157]

[0158]

[0159]

[0160]

[0161]

[0162]

[0163] Where Alk represents an unsubstituted or substituted alkyl group or optionally has R as given with respect to Formula I. 1 The meaning of "preferably" is a straight-chain alkyl group having 1 to 20 C atoms or a branched or cyclic alkyl group having 3 to 20 C atoms, more preferably a straight-chain alkyl group having 1 to 12 C atoms or a branched alkyl group having 3 to 18 C atoms.

[0164] In one embodiment, the compound of formula I contains exactly one donor group and exactly one acceptor group, particularly selected from groups D and A as defined herein, respectively.

[0165] Methods for preparing compounds of formula I may be based on or similar to known methods, such as those described in standard works of organic chemistry, such as, for example, Houben-Weyl, Methoden der organischen Chemie [Methods of Organic Chemistry], Thieme Verlag, Stuttgart. For specific methods for preparing compounds of formula I, see also the examples and known literature.

[0166] In one aspect of the invention, a method for preparing a compound of formula I is provided, wherein in the method, a bromine compound of formula I-Br is prepared or provided.

[0167]

[0168] Among them, D, A, Z 2 A 2 Q 2 R 2 "and o" has the meaning as described herein for compounds of formula I, wherein the I-Br compound is subsequently subjected to a chemical reaction, preferably a cross-coupling reaction.

[0169] As described herein, compounds of formula I exhibit a favorable large extinction coefficient, preferably in the visible light spectrum and / or in the NIR spectrum, particularly in the visible light spectrum.

[0170] In one embodiment, the compound of formula I has at least 500 (wt% * cm⁻¹). -1 Preferably at least 650 (wt% * cm) -1 More preferably at least 800 (wt% * cm) -1 And even more preferably at least 875 (wt% * cm) -1 The isotropic extinction coefficient.

[0171] The isotropic extinction coefficient is preferably determined according to the method described further below.

[0172] A high extinction coefficient, especially in combination with a high dichroism ratio, can produce several benefits. For example, a lower dye concentration can be used to obtain the desired contrast between the light and dark states, i.e., between a relatively high transmittance state and a relatively low transmittance state, and to obtain an effective dark state. A lower dye concentration can also be beneficial in terms of solubility or viscosity considerations. Similarly, and also in combination, for the dye compounds of this application with a high extinction coefficient, a single switching layer can be sufficient and / or a small switching layer thickness or cell gap is sufficient to obtain the desired switching contrast and the desired dark state performance.

[0173] The compound of Formula I is preferably a positive dichroic dye, that is, a dye with a positive anisotropy degree R.

[0174] The degree of anisotropy R of an LC mixture containing dye is determined by the extinction coefficient values ​​of molecules aligned parallel and perpendicular to the polarization direction of light.

[0175] According to the present invention, the degree of anisotropy R is preferably greater than 0.4, more preferably greater than 0.6, even more preferably greater than 0.7, and even more preferably greater than 0.75, and particularly greater than 0.8.

[0176] Absorption preferably reaches its maximum value when the polarization direction of the light is parallel to the longest molecular elongation direction of the compound of Formula I, and preferably reaches its minimum value when the polarization direction of the light is perpendicular to the longest molecular elongation direction of the compound of Formula I.

[0177] The compounds according to the invention preferably exhibit maximum absorption at wavelengths in the visible or NIR spectrum, more preferably at wavelengths in the visible spectrum.

[0178] Compounds of Formula I can be advantageously used as guest compounds in liquid crystal host mixtures, particularly as dichroic dyes. Therefore, in a preferred embodiment, (multiple) compounds of Formula I are dissolved in the LC medium.

[0179] In one aspect of the invention, the mesocrystalline medium comprises one or more compounds of Formula I as described in the context, preferably two or more compounds of Formula I as described in the context, more preferably three or more compounds of Formula I as described in the context.

[0180] In a preferred embodiment, the mesocrystalline medium comprises at least one compound selected from the group consisting of compounds of formulas I-1 and I-2 as set forth herein.

[0181] In a particularly preferred embodiment, the mesocrystalline medium comprises at least one compound of formula IA as described herein, more preferably at least two compounds of formula IA as described herein.

[0182] In principle, a suitable host mixture is any dielectric negative or positive LC mixture suitable for conventional VA, TN, STN, IPS or FFS displays.

[0183] Suitable LC mixtures are known in the art and described in the references. LC media with negative dielectric anisotropy for use in VA displays are described, for example, in EP 1 378 557 A1.

[0184] Suitable LC mixtures with positive dielectric anisotropy for LCDs and especially for IPS displays are known, for example, JP 07-181 439 (A), EP 0 667 555, EP 0 673 986, DE 195 09 410, DE 195 28 106, DE195 28 107, WO 96 / 23 851, WO 96 / 28 521 and WO2012 / 079676.

[0185] The following describes a preferred embodiment of a liquid crystal medium having negative or positive dielectric anisotropy according to the present invention.

[0186] The LC host mixture is preferably a nematic LC mixture. In one embodiment, the LC mixture does not have a chiral LC phase.

[0187] In one embodiment of the invention, the LC dielectric contains an LC bulk mixture having negative dielectric anisotropy. Therefore, in a preferred embodiment, the mesocrystalline dielectric according to the invention comprises a component selected from items a) to x):

[0188] a) A mesocrystalline medium comprising one or more compounds selected from the group consisting of compounds of formula CY, PY, and AC:

[0189]

[0190] in

[0191] 'a' represents 0, 1, or 2, preferably 1 or 2.

[0192] b represents 0 or 1.

[0193] c is 0, 1, or 2.

[0194] d is 0 or 1.

[0195] express or

[0196] and

[0197] express

[0198]

[0199] or ,and

[0200] express

[0201]

[0202] R 1 and R 2

[0203] R AC1 and R AC2 Each of the above independently represents an alkyl group having 1 to 12 carbon atoms, wherein, in addition, one or two non-adjacent CH2 groups may be replaced by -O-, -CH=CH-, -CO-, -OCO-, or -COO- in such a way that the O atoms are not directly connected to each other, preferably alkyl or alkoxy groups having 1 to 6 carbon atoms.

[0204] Z x and Z y Each can independently represent -CH2CH2-, -CH=CH-, -CF2O-, -OCF2-, -CH2O-, -OCH2-, -CO-O-, -O-CO-, -C2F4-, -CF=CF-, -CH=CH-CH2O-, or a single bond, preferably a single bond.

[0205] L 1-4 Each of them independently represents F, Cl, CN, OCF3, CF3, CH3, CH2F, and CHF2.

[0206] Some of these groups have the following meanings:

[0207] Each of these groups independently represents an alkyl group having 1 to 12 carbon atoms, wherein, in addition, one or two non-adjacent CH2 groups may be replaced by -O-, -CH=CH-, -CO-, -O-CO-, or -CO-O- in such a way that the O atoms are not directly connected to each other.

[0208] Z AC This represents -CH2CH2-, -CH=CH-, -CF2O-, -OCF2-, -CH2O-, -OCH2-, -CO-O-, -O-CO-, -C2F4-, -CF=CF-, -CH=CH-CH2O-, or a single bond, preferably a single bond.

[0209] Preferably, L 1 and L 2 Both 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 represent F or L. 3 and L 4 One of them represents F and the other represents Cl.

[0210] Compounds of formula CY are preferably selected from the group consisting of the following formulas:

[0211]

[0212]

[0213]

[0214]

[0215]

[0216] Where a represents 1 or 2, alkyl and alkyl* each independently represent a straight-chain alkyl group having 1 to 6 carbon atoms, alkenyl represents a straight-chain alkenyl group having 2 to 6 carbon atoms, and (O) represents an oxygen atom or a single bond. alkenyl preferably represents CH2=CH-, CH2=CHCH2CH2-, CH3-CH=CH-, CH3-CH2-CH=CH-, CH3-(CH2)2-CH=CH-, CH3-(CH2)3-CH=CH-, or CH3-CH=CH-(CH2)2-.

[0217] The PY compound is preferably selected from the group consisting of the following formulas:

[0218]

[0219]

[0220]

[0221] Wherein alkyl and alkyl* each independently represent a straight-chain alkyl group having 1 to 6 carbon atoms, alkenyl represents a straight-chain alkenyl group having 2 to 6 carbon atoms, and (O) represents an oxygen atom or a single bond. alkenyl preferably represents CH2=CH-, CH2=CHCH2CH2-, CH3-CH=CH-, CH3-CH2-CH=CH-, CH3-(CH2)2-CH=CH-, CH3-(CH2)3-CH=CH-, or CH3-CH=CH-(CH2)2-.

[0222] Compounds of formula AC are preferably selected from the group consisting of the following sub-formulas:

[0223]

[0224]

[0225] b) A mesocrystalline medium, which further comprises one or more compounds of the following formula:

[0226]

[0227] Some of these groups have the following meanings:

[0228] express

[0229] or

[0230] express or

[0231] R 3 and R 4 Each of these terms independently represents an alkyl group having 1 to 12 carbon atoms, wherein, additionally, one or two non-adjacent CH2 groups may be replaced by -O-, -CH=CH-, -CO-, -O-CO-, or -CO-O- in such a way that the O atoms are not directly connected to each other.

[0232] Z yIt represents -CH2CH2-, -CH=CH-, -CF2O-, -OCF2-, -CH2O-, -OCH2-, -CO-O-, -O-CO-, -C2F4-, -CF=CF-, -CH=CH-CH2O- or a single bond, preferably a single bond.

[0233] Compounds of formula ZK are preferably selected from the group consisting of the following formulas:

[0234]

[0235] Wherein alkyl and alkyl* each independently represent a straight-chain alkyl group having 1 to 6 carbon atoms, and alkenyl represents a straight-chain alkenyl group having 2 to 6 carbon atoms. 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-.

[0236] Compounds of formula ZK1 and ZK3 are particularly preferred.

[0237] The particularly preferred ZK compounds are selected from the following sub-formulas:

[0238]

[0239] Among them, propyl, butyl, and pentyl are straight-chain groups.

[0240] The most preferred compounds are those of formula ZK1a and ZK3a.

[0241] c) A mesocrystalline medium, which further comprises one or more compounds of the following formula:

[0242]

[0243] Some of these groups, when appearing each time, have the same or different meanings as follows:

[0244] R 5 and R 6 Each of the above independently represents an alkyl group having 1 to 12 carbon atoms, wherein, in addition, one or two non-adjacent CH2 groups may be replaced by -O-, -CH=CH-, -CO-, -OCO-, or -COO- in such a way that the O atoms are not directly connected to each other, preferably alkyl or alkoxy groups having 1 to 6 carbon atoms.

[0245] express or

[0246] express or and

[0247] e represents 1 or 2.

[0248] Compounds of formula DK are preferably selected from the group consisting of the following formulas:

[0249]

[0250]

[0251]

[0252] Wherein alkyl and alkyl* each independently represent a straight-chain alkyl group having 1 to 6 carbon atoms, and alkenyl represents a straight-chain alkenyl group having 2 to 6 carbon atoms. 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-.

[0253] The preferred compounds are those of formulas DK1, DK4, DK7, DK9, DK10, and DK11.

[0254] d) A mesocrystalline medium, which further comprises one or more compounds of the following formula:

[0255]

[0256] Some of these groups have the following meanings:

[0257] express

[0258] or

[0259] At least one of the rings F is different from the subcyclohexyl group.

[0260] f represents 1 or 2.

[0261] R 1 and R 2 Each of these terms independently represents an alkyl group having 1 to 12 carbon atoms, wherein, additionally, one or two non-adjacent CH2 groups may be replaced by -O-, -CH=CH-, -CO-, -OCO-, or -COO- in such a way that the O atoms are not directly connected to each other.

[0262] Z xThis represents -CH2CH2-, -CH=CH-, -CF2O-, -OCF2-, -CH2O-, -OCH2-, -CO-O-, -O-CO-, -C2F4-, -CF=CF-, -CH=CH-CH2O-, or a single bond, preferably a single bond.

[0263] L 1 and L 2 Each of them independently represents F, Cl, OCF3, CF3, CH3, CH2F, and CHF2.

[0264] Preferably, the two groups L 1 and L 2 Both represent F or the group L. 1 and L 2 One of them represents F and the other represents Cl.

[0265] Compounds of formula LY are preferably selected from the group consisting of the following formulas:

[0266]

[0267]

[0268]

[0269] Where R 1 With the meanings indicated above, alkyl refers to a straight-chain alkyl group having 1 to 6 carbon atoms, (O) represents an oxygen atom or a single bond, and v represents an integer from 1 to 6. R 1 Preferably, it represents a straight-chain alkyl group having 1 to 6 carbon atoms or a straight-chain alkenyl group having 2 to 6 carbon atoms, especially 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-.

[0270] e) A mesocrystalline medium, which further comprises one or more compounds selected from the group consisting of the following formulas:

[0271]

[0272]

[0273] Where alkyl represents C 1-6 -alkyl, L xH or F is represented, and X represents F, Cl, OCF3, OCHF2, or OCH=CF2. Compounds of formula G1 are particularly preferred, where X represents F.

[0274] f) A mesocrystalline medium, which further comprises one or more compounds selected from the group consisting of the following formulas:

[0275]

[0276]

[0277]

[0278] Where R 5 With the above for R 1 One of the meanings indicated is that alkyl represents C. 1-6 -alkyl, d represents 0 or 1, and z and m each independently represent integers from 1 to 6. R in these compounds 5 C is particularly preferred 1-6 -alkyl or -alkoxy or C 2-6 -Alkenyl, d is preferably 1. The LC medium according to the invention preferably contains one or more compounds of the formula mentioned above in ≥ 5% by weight.

[0279] g) A mesocrystalline medium, further comprising one or more biphenyl compounds selected from the group consisting of the following:

[0280]

[0281] Wherein alkyl and alkyl* each independently represent a straight-chain alkyl group having 1 to 6 carbon atoms, and alkenyl and alkenyl* each independently represent a straight-chain alkenyl group having 2 to 6 carbon atoms. alkenyl and alkenyl* preferably represent 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-.

[0282] The proportion of biphenyls of formulas B1 to B3 in the LC mixture is preferably at least 3% by weight, and in particular ≥ 5% by weight.

[0283] Compound B2 is particularly preferred.

[0284] Compounds of formulas B1 to B3 are preferably selected from the group consisting of the following formulas:

[0285]

[0286] Wherein alkyl* represents an alkyl group having 1 to 6 carbon atoms. The medium according to the invention particularly preferably comprises one or more compounds of formula B1a and / or B2c.

[0287] h) A mesocrystalline medium, which further comprises one or more terphenyl compounds of the following formula:

[0288]

[0289] Where R 5 and R 6 Each independently possesses one of the meanings indicated above, and

[0290] and

[0291] Each represents independently of the other.

[0292] or

[0293] Where L 5 Represented as F or Cl, preferably F, and L 6 It can be represented by F, Cl, OCF3, CF3, CH3, CH2F or CHF2, with F being the preferred one.

[0294] Compounds of formula T are preferably selected from the group consisting of the following formulas:

[0295]

[0296]

[0297]

[0298]

[0299] Wherein R represents a straight-chain alkyl or alkoxy group having 1 to 7 carbon atoms, R* represents a straight-chain alkenyl group having 2 to 7 carbon atoms, (O) represents an oxygen atom or a single bond, and m represents an integer from 1 to 6. 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-.

[0300] R preferably represents methyl, ethyl, propyl, butyl, pentyl, hexyl, methoxy, ethoxy, propoxy, butoxy, or pentoxy.

[0301] i) A mesocrystalline medium, which further comprises one or more O compounds of the following formula:

[0302]

[0303] in

[0304] express or

[0305] express

[0306] or

[0307] R O1 R O2 Each of these terms independently represents an alkyl group having 1 to 12 carbon atoms, wherein, additionally, one or two non-adjacent CH2 groups may be replaced by -O-, -CH=CH-, -CO-, -OCO-, or -COO- in such a way that the O atoms are not directly connected to each other.

[0308] Z O1 This indicates -CH2CH2-, -CF2CF2-, -C=C-, or a single bond.

[0309] Z O2 This indicates CH2O, -C(O)O-, -CH2CH2-, -CF2CF2-, or a single bond.

[0310] o is 1 or 2.

[0311] Compounds of formula O are preferably selected from the group consisting of the following formulas:

[0312]

[0313]

[0314] Where R O1 and R O2 With the meaning indicated above and preferably each independently representing a straight-chain alkyl group having 1 to 6 carbon atoms or a straight-chain alkenyl group having 2 to 6 carbon atoms.

[0315] The preferred medium comprises one or more compounds selected from the formulas O3, O4, and O5.

[0316] k) A mesocrystalline medium, which further comprises one or more compounds of the following formula:

[0317]

[0318] in

[0319] express

[0320]

[0321]

[0322] R 9 (H, CH3, C2H5, or n-C3H7) represents H, CH3, C2H5, or n-C3H7, (F) represents an optional fluorine substituent, and q represents 1, 2, or 3, and R represents... 7 With R 1 One of the meanings of the indication is preferably >3% by weight, especially ≥5% by weight and very particularly preferably 5 to 30% by weight.

[0323] The particularly preferred FI compounds are selected from the group consisting of the following formulas:

[0324]

[0325]

[0326] Where R 7 Preferably, it represents a straight-chain alkyl group, and R 9 It represents CH3, C2H5, or n-C3H7. Compounds of formulas FI1, FI2, and FI3 are particularly preferred.

[0327] l) A mesocrystalline medium, further comprising one or more compounds selected from the group consisting of the following formulas:

[0328]

[0329]

[0330] Where R 8 With R 1 The meaning of the indication is that alkyl refers to a straight-chain alkyl group having 1 to 6 carbon atoms.

[0331] m) A mesocrystalline medium, which further comprises one or more compounds containing tetrahydronaphthyl or naphthyl units, such as, for example, compounds selected from the group consisting of the following formulas:

[0332]

[0333]

[0334] in

[0335] R 10 and R 11Each of the above independently represents an alkyl group having 1 to 12 carbon atoms, wherein, in addition, one or two non-adjacent CH2 groups may be replaced by -O-, -CH=CH-, -CO-, -OCO-, or -COO- in such a way that the O atoms are not directly connected to each other, preferably alkyl or alkoxy groups having 1 to 6 carbon atoms.

[0336] and R 10 and R 11 Preferably, it represents a straight-chain alkyl or alkoxy group having 1 to 6 carbon atoms or a straight-chain alkenyl group having 2 to 6 carbon atoms, and

[0337] Z 1 and Z 2 Each of these can be represented independently as -C2H4-, -CH=CH-, -(CH2)4-, -(CH2)3O-, -O(CH2)3-, -CH=CH-CH2CH2-, -CH2CH2CH=CH-, -CH2O-, -OCH2-, -CO-O-, -O-CO-, -C2F4-, -CF=CF-, -CF=CH-, -CH=CF-, -CH2-, or a single bond.

[0338] n) A mesocrystalline medium, further comprising one or more difluorodibenzo-p-methyl chromatographs and / or chromatographs of the following formula:

[0339]

[0340] in

[0341] R 11 and R 12 Each of them independently possesses the characteristics described above for R. 11 One of the meanings of the instruction

[0342] Ring M is trans-1,4-cyclohexene or 1,4-phenylene.

[0343] Z m It is -C2H4-, -CH2O-, -OCH2-, -CO-O-, or -O-CO-.

[0344] c is 0, 1, or 2.

[0345] Preferably, it is in an amount of 3 to 20% by weight, and in particular, in an amount of 3 to 15% by weight.

[0346] The particularly preferred compounds of formula BC, CR, and RC are selected from the group consisting of the following formulas:

[0347]

[0348]

[0349]

[0350] Wherein alkyl and alkyl* each independently represent a straight-chain alkyl group having 1 to 6 carbon atoms, (O) represents an oxygen atom or a single bond, and c is 1 or 2, and alkenyl and alkenyl* each independently represent a straight-chain alkenyl group having 2 to 6 carbon atoms. alkenyl and alkenyl* preferably represent CH2=CH-, CH2=CHCH2CH2-, CH3-CH=CH-, CH3-CH2-CH=CH-, CH3-(CH2)2-CH=CH-, CH3-(CH2)3-CH=CH-, or CH3-CH=CH-(CH2)2-.

[0351] Very particularly preferred is a mixture comprising one, two or three BC-2 compounds.

[0352] o) A mesocrystalline medium, which further comprises one or more fluorophenanthrenes and / or dibenzofurans of the following formula:

[0353]

[0354] Where R 11 and R 12 Each of them independently possesses the characteristics described above for R. 11 One of the meanings of the indication is that b represents 0 or 1, L represents F, and r represents 1, 2, or 3.

[0355] The particularly preferred PH and BF compounds are selected from the group consisting of the following formulas:

[0356]

[0357]

[0358] R and R' each independently represent a straight-chain alkyl or alkoxy group having 1 to 7 carbon atoms.

[0359] In another embodiment, the liquid crystal medium comprises one or more compounds selected from the group consisting of compounds of formula B-1, B-2, and B-3:

[0360]

[0361] in

[0362] R 11 and R 12 The same or different representations of H or a straight-chain alkyl or alkoxy group having 1 to 15 C atoms, wherein one or more CH2 groups among these groups are optionally independently represented by -C≡C-, -CF2O-, -OCF2-, -CH=CH-, , , -O-, -CO-O-, or -O-CO- are substituted in such a way that the O atoms are not directly connected to each other, and one or more of the H atoms can be substituted with halogens.

[0363] Preferably, it is a straight-chain alkoxy group having 1 to 7 carbon atoms.

[0364] Compounds of formula B-1 are preferably selected from the group consisting of compounds of formulas B-1-a to B-1-e:

[0365]

[0366] Where R 11 and R 12 The same or different refers to alkyl groups having 1 to 7 carbon atoms, preferably ethyl, n-propyl, n-butyl or n-pentyl.

[0367] Compounds of formula B-2 are preferably selected from the group consisting of compounds of formulas B-2-a to B-2-e:

[0368]

[0369] Where R 11 and R 12 Alkyl groups having 1 to 12 carbon atoms, or different from other alkyl groups, are preferred to have 1 to 7 carbon atoms.

[0370] Compounds of formula B-3 are preferably selected from the group consisting of compounds of formulas B-3-a to B-3-j:

[0371]

[0372]

[0373] Where R 12 It indicates an alkyl group having 1 to 7 carbon atoms, preferably ethyl, n-propyl or n-butyl.

[0374] In a preferred embodiment, one or more compounds selected from the group consisting of compounds of formulas B-1, B-2, and B-3 are selected from the group consisting of compounds BA to BJ:

[0375]

[0376]

[0377] One or more compounds selected from the group consisting of compounds of formula B-1, B-2 and B-3 are preferably contained in the liquid crystal medium in a total amount of 0 to 15% by weight, more preferably 10% by weight or less and even more preferably 5% by weight or less.

[0378] p) A mesocrystalline medium, which further comprises one or more monocyclic compounds of the following formula:

[0379]

[0380] in

[0381] R 1 and R 2 Each of the above independently represents an alkyl group having 1 to 12 carbon atoms, wherein, in addition, one or two non-adjacent CH2 groups may be replaced by -O-, -CH=CH-, -CO-, -OCO-, or -COO- in such a way that the O atoms are not directly connected to each other, preferably alkyl or alkoxy groups having 1 to 6 carbon atoms.

[0382] L 1 and L 2 Each of them independently represents F, Cl, OCF3, CF3, CH3, CH2F, and CHF2.

[0383] Preferably, L 1 and L 2 Both represent F or L. 1 and L 2 One of them represents F and the other represents Cl.

[0384] Compound Y is preferably selected from the group consisting of the following formulas:

[0385]

[0386]

[0387] Wherein, Alkyl and Alkyl* each independently represent a straight-chain alkyl group having 1 to 6 carbon atoms, Alkoxy represents a straight-chain alkoxy group having 1 to 6 carbon atoms, Alkenyl and Alkenyl* each independently represent a straight-chain alkenyl group having 2 to 6 carbon atoms, and O represents an oxygen atom or a single bond. Alkenyl and Alkenyl* preferably represent 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-.

[0388] The particularly preferred compound of formula Y is selected from the group consisting of the following formulas:

[0389]

[0390] Alkoxy preferably refers to a straight-chain alkoxy group having 3, 4, or 5 C atoms.

[0391] q) A mesocrystalline medium comprising 1 to 15, preferably 3 to 12, compounds of the formula CY1, CY2, PY1, PY2, AC1, AC2, and / or AC3. The overall proportion of these compounds in the mixture is preferably 20 to 99%, more preferably 30 to 95%, and particularly preferably 40 to 90%. The content of such individual compounds is preferably 2 to 20% in each case.

[0392] r) A mesocrystalline medium comprising 1 to 10, preferably 1 to 8, compounds of formula ZK, particularly compounds of formula ZK1, ZK2, and / or ZK6. The overall proportion of these compounds in the mixture is preferably 3 to 25%, particularly preferably 5 to 45%. The content of such individual compounds is preferably 2 to 20% in each case.

[0393] s) A mesocrystalline medium, wherein the proportion of compounds of formula CY, PY and ZK in the mixture is greater than 70%, preferably greater than 80%.

[0394] t) A mesocrystalline medium containing one or more, preferably one to five compounds selected from the group consisting of formulas PY1 to PY8, and very preferably a compound of formula PY2. The overall proportion of these compounds in the mixture is preferably 1 to 30%, particularly preferably 2 to 20%. The content of such individual compounds is preferably 1 to 20% in each case.

[0395] u) A mesocrystalline medium containing one or more, preferably 1, 2 or 3, T2 compounds. The overall content of these compounds in the mixture is preferably 1 to 20%.

[0396] The LC medium according to the invention preferably contains terphenyl of formula T and its preferred derivative in an amount of 0.5 to 30% by weight, particularly 1 to 20% by weight.

[0397] Particularly preferred are compounds of formulas T1, T2, T3, and T21. In these compounds, R preferably represents an alkyl group, and may also represent an alkoxy group, each having 1 to 5 carbon atoms.

[0398] If the Δn value of the mixture is to be ≥ 0.1, terphenyl is preferably used in the mixture according to the invention. The preferred mixture contains 2 to 20% by weight of one or more terphenyl compounds of formula T, preferably selected from the group consisting of compounds T1 to T22.

[0399] v) A mesocrystalline medium containing one or more, preferably one, two or three, BF1 and / or BSF1 compounds. The total content of these compounds in the mixture is preferably 1 to 15%, more preferably 2 to 10%, and particularly preferably 4 to 8%.

[0400] w) The preferred medium contains one or more compounds of formula O, preferably selected from compounds of formula O3, O4 and O5, at a total concentration of 2 to 25%, more preferably 3 to 20%, particularly preferably 5 to 15%.

[0401] x) The preferred medium comprises one or more compounds of formula DK, preferably selected from compounds of formula DK1, DK4, DK7, DK9, DK10, and DK11. The total concentration of compounds of formula DK9, DK10, and DK11 is preferably 2 to 25%, more preferably 3 to 20%, and particularly preferably 5 to 15%.

[0402] In another embodiment of the invention, the LC medium comprises an LC bulk mixture having positive dielectric anisotropy. Therefore, in other preferred embodiments, the mesocrystalline medium according to the invention comprises a component selected from the following entries aa) to zz):

[0403] aa) A mesocrystalline medium comprising one or more compounds selected from the group consisting of compounds of formulas II to VIII as set forth below, particularly compounds of formulas II and III:

[0404]

[0405] in

[0406] R 20 Each may be identical or different from a halosubstituted or unsubstituted alkyl or alkoxy group having 1 to 15 carbon atoms, wherein, additionally, one or more CH2 groups in such groups may be independently converted to -C≡C-, -CF2O-, -CH=CH-, -O-, -CO-O-, or -O-CO- are replaced by O atoms that are not directly connected to each other.

[0407] X 20 Each may be identical or different from F, Cl, CN, SF5, SCN, NCS, haloalkyl, haloalkenyl, haloalkoxy, or haloalkenoxy, each having up to 6 carbon atoms, and

[0408] Y 20-24 Each may represent H or F in the same or different ways;

[0409] and Each represents independently of the other.

[0410]

[0411] or .

[0412] Compounds of formula II are preferably selected from the following formula:

[0413]

[0414]

[0415] Where R 20 and X 20 It has the meaning indicated above.

[0416] R 20 Preferably, it refers to an alkyl group having 1 to 6 carbon atoms. 20 F is preferred. Compounds of formula IIa and IIb are particularly preferred, especially compounds of formula IIa and IIb, wherein X represents F.

[0417] In one embodiment, the liquid crystal medium comprises one or more compounds selected from the group consisting of compounds of formula II-1 and II-2:

[0418]

[0419]

[0420] in

[0421] R 2 This indicates an alkyl, alkoxy, fluoroalkyl, or fluoroalkoxy group having 1 to 7 carbon atoms, or an alkenyl, alkenyloxy, alkoxyalkyl, or fluoroalkenyl group having 2 to 7 carbon atoms.

[0422] Optionally, one or more CH2 groups can be independently converted to carbon dioxide. , , , or Replacement

[0423] and Independent of each other

[0424]

[0425] or ,

[0426] L 21 L 22 L 23 and L 24 H or F can be represented independently of each other.

[0427] L 25 Indicates H or CH3, and

[0428] X 2 It represents halogen, haloalkyl or alkoxy with 1 to 3 carbon atoms, or haloalkenyl or alkenoxy with 2 or 3 carbon atoms.

[0429] In another embodiment, the liquid crystal medium comprises one or more compounds selected from the group consisting of compounds of formulas II-1-a to II-1-h:

[0430]

[0431]

[0432] Where R 2 It has the meaning given in Equation II-1.

[0433] In another embodiment, the liquid crystal medium comprises one or more compounds selected from compounds of formulas II-2-a to II-2-l:

[0434]

[0435]

[0436] Where R 2 It has the meaning given for Equation II-2 above.

[0437] Compounds of formula III are preferably selected from the following formula:

[0438]

[0439] Where R 20 and X 20 It has the meaning indicated above.

[0440] R 20 Preferably, it refers to an alkyl group having 1 to 6 carbon atoms. 20 F is preferred. Compounds of formula IIIa and IIIe are particularly preferred, especially compounds of formula IIIa;

[0441] bb) A mesocrystalline medium that optionally or otherwise comprises one or more compounds selected from the following:

[0442]

[0443] in

[0444] R 20 X 20 and Y 20-23 It has the meaning indicated above, and

[0445] Z 20The symbols -C2H4-, -(CH2)4-, -CH=CH-, -CF=CF-, -C2F4-, -CH2CF2-, -CF2CH2-, -CH2O-, -OCH2-, -COO-, or -OCF2- represent single bonds in formulas V and VI, and -CF2O- in formulas V and VIII.

[0446] r represents 0 or 1, and

[0447] s represents 0 or 1;

[0448] - Compounds of formula IV are preferably selected from the following formula:

[0449]

[0450] Where R 20 and X 20 It has the meaning indicated above.

[0451] R 20 Preferably, it refers to an alkyl group having 1 to 6 carbon atoms. 20 Preferably, it represents F, CN, or OCF3; it can also represent OCF=CF2 or Cl.

[0452] - Compounds of formula V are preferably selected from the following formula:

[0453]

[0454]

[0455] Where R 20 and X 20 It has the meaning indicated above.

[0456] R 20 Preferably, it refers to an alkyl group having 1 to 6 carbon atoms. 20 The preferred representations are F and OCF3, and also OCHF2, CF3, OCF=CF2 and OCH=CF2;

[0457] - Compounds of formula VI are preferably selected from the following formula:

[0458]

[0459] Where R 20 and X 20 It has the meaning indicated above.

[0460] R 20 Preferably, it refers to an alkyl group having 1 to 6 carbon atoms. 20 The preferred representation is F, and other options include OCF3, CF3, CF=CF2, OCHF2, and OCH=CF2;

[0461] - Compounds of formula VII are preferably selected from the following formulas:

[0462]

[0463] Where R 20 and X 20 It has the meaning indicated above.

[0464] R 20 Preferably, it refers to an alkyl group having 1 to 6 carbon atoms. 20 The preferred option is F, which also represents OCF3, OCHF2, and OCH=CF2.

[0465] (cc) Mesocrystalline medium, further comprising one or more compounds selected from the formulas ZK1 to ZK10 given above. Compounds of formulas ZK1 and ZK3 are particularly preferred. Compounds of formula ZK are especially preferred selected from sub-formulas ZK1a, ZK1b, ZK1c, ZK3a, ZK3b, ZK3c and ZK3d.

[0466] (dd) The mesocrystalline medium further comprises one or more compounds selected from the formulas DK1 to DK12 given above. Particularly preferred compounds are DK1, DK4, DK7, DK9, DK10 and DK11.

[0467] (ee) The mesocrystalline medium further comprises one or more compounds selected from the following formula:

[0468]

[0469] Where X 20 It has the meaning of the instructions above.

[0470] L represents H or F, and

[0471] “alkenyl” indicates C 2-6 -Alkenyl.

[0472] The compounds of formula DK-3a and IX are preferably selected from the following formula:

[0473]

[0474] Where "alkyl" represents C 1-6 -alkyl group, preferably n-C3H7, n-C4H9 or n-C5H 11 Especially for n-C3H7.

[0475] (gg) The medium further comprises one or more compounds selected from the formulas B1, B2 and B3 given above, preferably selected from formula B2. Compounds of formulas B1 to B3 are particularly preferably selected from formulas B1a, B2a, B2b and B2c.

[0476] hh) The medium also contains one or more compounds selected from the following formula:

[0477]

[0478] Where L 20 L 21 Represents H or F, and R 21 and R 22 Each of the following may be an alkyl group, alkoxy group, oxalyl group, fluoroalkyl group, or alkenyl group, each having up to 6 carbon atoms, and preferably each of the following may be an alkyl group having 1 to 6 carbon atoms.

[0479] ii) The medium contains one or more compounds of the following formula:

[0480]

[0481] Where R 20 X 20 and Y 20-23 Having the meaning indicated in Formula III, and

[0482] and Each represents independently of the other.

[0483] or

[0484] and

[0485] express

[0486] or .

[0487] Compounds of formula XI and XII are preferably selected from the following formulas:

[0488]

[0489]

[0490]

[0491] Where R 20 and X 20 Having the meaning indicated above and preferably R 20 It represents an alkyl group having 1 to 6 carbon atoms, and X 20 It represents F.

[0492] The mixtures according to the invention particularly preferably contain at least one compound of formula XIIa and / or XIIe.

[0493] jj) The medium comprises one or more compounds of formula T given above, preferably selected from the group consisting of compounds of formulas T21 to T23 and T25 to T27.

[0494] Compounds of formulas T21 to T23 are particularly preferred. Compounds of the following formulas are very particularly preferred:

[0495]

[0496] The medium contains one or more compounds selected from the group consisting of the formulas DK9, DK10 and DK11 given above.

[0497] ll) The medium further comprises one or more compounds selected from the following formula:

[0498]

[0499]

[0500] Where R 20 and X 20 Each of them independently possesses one of the meanings indicated above, and Y 20-23 Each can be represented independently of the other, either H or F. X 20 Preferably, it contains F, Cl, CF3, OCF3, or OCHF2. 20 Preferably, it represents an alkyl, alkoxy, oxaalkyl, fluoroalkyl, or alkenyl group, each having up to 6 carbon atoms.

[0501] The mixtures according to the invention particularly preferably contain one or more compounds of formula XVIII-a.

[0502]

[0503] Where R 20 It has the meaning indicated above. R 20 Preferably, it represents a straight-chain alkyl group, particularly ethyl, n-propyl, n-butyl, and n-pentyl, and very particularly preferably n-propyl. Compounds of formula XVIII, particularly XVIII-a, are preferably used in mixtures according to the invention in an amount of 0.5 to 20% by weight, particularly preferably 1 to 15% by weight.

[0504] The medium (mm) also contains one or more compounds of formula XIX.

[0505]

[0506] Where R 20 X20 and Y 20-25 Having the meaning indicated in Equation III, s represents 0 or 1, and

[0507] express or .

[0508] In equation XIX, X 20 It may also represent an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms. The alkyl or alkoxy group is preferably straight-chain.

[0509] R 20 Preferably, it refers to an alkyl group having 1 to 6 carbon atoms. 20 Preferred option is F;

[0510] - Compounds of formula XIX are preferably selected from the following formula:

[0511]

[0512]

[0513] Where R 20 X 20 and Y 20 It has the meaning indicated above. R 20 Preferably, it refers to an alkyl group having 1 to 6 carbon atoms. 20 Preferred representations are F and Y. 20 F is preferred;

[0514] - Preferred

[0515]

[0516] or

[0517] - R 20 It is a straight-chain alkyl or alkenyl group having 2 to 6 carbon atoms.

[0518] The medium comprises one or more compounds of formulas G1 to G4 given above, preferably selected from compounds G1 and G2, wherein alkyl represents C. 1-6 -alkyl, L x Let H represent H, and let X represent F or Cl. In G2, X is particularly preferably Cl.

[0519] (oo) The medium contains one or more compounds of the following formula:

[0520]

[0521] Where R 20 and X 20 It has the meaning indicated above. R 20 Preferably, it refers to an alkyl group having 1 to 6 carbon atoms. 20 Preferably, F is represented. The medium according to the invention particularly preferably comprises one or more compounds of formula XXII, wherein X... 20 Preferred to be F. Compounds of formula XX to XXII are preferably 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 contain at least one compound of formula XXII.

[0522] (pp) This medium contains one or more compounds of the following formulas: pyrimidine or pyridine.

[0523]

[0524] Where R 20 and X 20 It has the meaning indicated above. R 20 Preferably, it refers to an alkyl group having 1 to 6 carbon atoms. 20 Preferably, F is represented. The medium according to the invention particularly preferably comprises one or more compounds of formula M-1, wherein X 20 The preferred designation is F. Compounds of formula M-1 to M-3 are preferably used in the mixtures according to the invention in an amount of 1 to 20% by weight, particularly preferably 1 to 15% by weight.

[0525] (qq) The medium contains two or more compounds of formula XII, particularly formula XIIa and / or XIIe.

[0526] The medium contains 2 to 30% by weight, preferably 3 to 20% by weight, and particularly preferably 3 to 15% by weight of a compound of formula XII.

[0527] In addition to the compound of formula XII, the medium contains other compounds selected from the group consisting of compounds of formulas II to XVIII.

[0528] The proportion of compounds of formula II to XVIII in the mixture is 40 to 95% by weight, preferably 50 to 90% by weight, and particularly preferably 55 to 88% by weight.

[0529] The medium preferably contains 10 to 40% by weight, more preferably 12 to 30% by weight, and particularly preferably 15 to 25% by weight of compounds of formula II and / or III.

[0530] The medium contains 1 to 10% by weight, particularly preferably 2 to 7% by weight, of compounds of formula XV and / or XVI.

[0531] The medium contains at least one compound of formula XIIa and / or at least one compound of formula XIIe and at least one compound of formula IIIa and / or IIa.

[0532] (xx) The preferred medium contains one or more compounds of formula O at a total concentration of 2 to 25%, preferably 3 to 20%, particularly preferably 5 to 15%, preferably selected from compounds of formula O3, O4 and O5.

[0533] The preferred medium comprises one or more compounds of formula DK, preferably selected from compounds of formula DK1, DK4, DK7, DK9, DK10, and DK11. The total concentration of compounds of formula DK9, DK10, and DK11 is preferably 2 to 25%, more preferably 3 to 20%, and particularly preferably 5 to 15%.

[0534] (zz) The preferred medium contains one or more compounds of formula IV to VI at a concentration of 10 to 80% by weight, preferably 12 to 75% by weight, particularly preferably 15 to 70% by weight, preferably selected from the group consisting of compounds of formula IVa, IVb, IVc, IVd, Va, Vc and VIb.

[0535] When the dielectric has negative dielectric anisotropy, the value of the dielectric anisotropy (Δε) is preferably in the range of -2.0 to -8.0, more preferably in the range of -3.0 to -6.0, and particularly preferably in the range of -3.5 to -5.0.

[0536] When the dielectric has positive permittivity anisotropy, the value of Δε is preferably in the range of 2.5 to 50.0, more preferably in the range of 5.0 to 25.0, and particularly preferably in the range of 8.0 to 15.0.

[0537] The liquid crystal medium according to the invention preferably has a clearing point of 70°C or higher, more preferably 80°C or higher, even more preferably 90°C or higher, even more preferably 105°C or higher, and particularly preferably 110°C or higher. In one embodiment, the liquid crystal medium according to the invention has a clearing point in the range of 70°C to 170°C.

[0538] High-resolution bright spots, as defined herein, can be advantageous in terms of the performance and reliability of devices using liquid crystal media. In particular, the medium can maintain its functional properties over a suitable wide temperature range and even at high temperatures. This is particularly advantageous for window elements that regulate the passage of sunlight, especially when the window element is exposed to direct or prolonged sunlight. The high-resolution bright spots also contribute to a favorable high degree of ordering of the liquid crystal host molecules, and thus to the ordering of dichroic dye guest molecules at typical operating temperatures, which can increase the contrast available between switching states.

[0539] The clearing point (particularly the phase transition temperature between the nematic and isotropic phases) can be measured and determined by commonly known methods, such as using a Mettler oven, a hot stage under a polarizing microscope, or differential scanning calorimetry (DSC). According to the invention, the clearing point is preferably determined using a Mettler oven.

[0540] The nematic phase of the medium according to the invention preferably extends from at least -10°C or less to 80°C or greater. Even a wider range of nematic phases is preferred, particularly extending to up to 90°C or greater, more preferably from at least -20°C or less to 100°C or greater, and particularly preferably from -30°C or less to 110°C or greater.

[0541] In a preferred embodiment of the invention, the birefringence (Δn) of the liquid crystal medium is in the range of 0.010 or greater to 0.350 or less, more preferably in the range of 0.035 or greater to 0.300 or less, even more preferably in the range of 0.050 or greater to 0.250 or less, even more preferably in the range of 0.075 or greater to 0.200 or less, and particularly in the range of 0.010 or greater to 0.150 or less.

[0542] Compounds selected from the group consisting of compounds of formula I as described in the context are preferably present in the mesocrystalline medium at a concentration of 0.01% to 15% by weight, more preferably 0.025% to 10% by weight, even more preferably 0.05% to 7.5% by weight, even more preferably 0.1% to 5% by weight, and particularly 0.2% to 2% by weight. In one specific embodiment, the dye compound according to the invention is present in the medium at a concentration in the range of 0.05% to 1% by weight.

[0543] In one embodiment, the mesocrystalline medium contains two or more compounds selected from the group consisting of compounds of Formula I as described in the context, wherein the total concentration of these compounds in the medium is particularly preferably in the range of 0.05 wt% to 15 wt%, and even more preferably 0.1 wt% to 10 wt%, and particularly 0.2 wt% to 5 wt%. In this case, it is particularly preferred that individual dye compounds are present in the medium at a concentration in the range of 0.025 wt% to 5 wt%, and even more preferably 0.05 wt% to 2.5 wt%, and particularly 0.1 wt% to 1 wt%.

[0544] The medium preferably comprises one, two, three, four, five, six, seven, eight, or nine compounds of formula I according to the invention. In one specific embodiment, the medium comprises at least three compounds selected from the group consisting of compounds of formulas I-1 and I-2.

[0545] The LC medium according to the present invention is preferably a nematic liquid crystal.

[0546] The medium according to the invention is prepared in its conventional manner. Generally, the components are dissolved in each other, preferably at high temperatures. Mixing is preferably carried out under an inert gas, such as nitrogen or argon. Subsequently, one or more Formula I dyes and optionally other dichroic dyes are added, preferably at high temperatures, more preferably above 40°C and particularly preferably above 50°C. Generally, the required amount of the component used in a smaller quantity is dissolved in the component constituting the main component. Alternatively, the component can be mixed in a solution in an organic solvent (e.g., in acetone, toluene, chloroform, or methanol), and the solvent is removed again after mixing, for example by distillation.

[0547] The present invention also relates to a method for preparing a mesocrystalline medium according to the present invention.

[0548] The present invention also relates to the use of an LC medium comprising at least one compound of formula I in a guest-subject type liquid crystal device, wherein the device is particularly a window assembly or display. In this device, the compound and medium according to the invention are preferably disposed in one or more switching layers.

[0549] In a preferred embodiment, the device (particularly the window) contains only a single switching layer.

[0550] Furthermore, the present invention relates to a subject-object type liquid crystal display containing an LC medium comprising at least one compound of formula I.

[0551] The present invention also relates to the use of a mixture comprising a liquid crystal medium and at least one compound of formula I in a device for regulating the flow of energy through an external space into an internal space.

[0552] In one specific embodiment, in addition to one or more compounds selected from Formula I and preferably a liquid crystal medium, the device according to the invention preferably also includes other dichroic dyes having a structure different from Formula I in the switching layer. It particularly preferably includes one, two, three, four, five, six, seven, or eight other dyes, and most preferably includes two or three other dyes having a structure different from Formula I.

[0553] Regarding the properties of dichroism, the preferred properties described for compounds of Formula I are also preferred for any other dichroic dyes.

[0554] The absorption spectra of the dichroic dyes in the switching layer are preferably complementary to each other in a way that produces the impression of black or, respectively, gray or neutral color in the eye. Preferably, the two or more dichroic dyes in the liquid crystal medium according to the invention cover most of the visible spectrum, more preferably the entire visible spectrum. Precise methods for preparing mixtures of dyes that appear black or gray to the eye are known in the art and described, for example, in M. Richter, *Einführung in dieFarbmetrik* [Introduction to Colorimetry], 2nd edition, 1981, ISBN 3-11-008209-8, Walter de Gruyter & Co.

[0555] The determination of the color positions of a dye mixture is described within the field of colorimetry. To this end, the Lambert-Beer law is considered to calculate the spectra of individual dyes to generate the overall spectrum, which is then converted, according to colorimetric rules, into corresponding color positions and brightness values ​​under relevant illumination (e.g., daylight source D65). The positions of the white points are fixed by the corresponding light source (e.g., D65) and are cited in tables (e.g., in the references above). Different color positions can be determined by varying the proportions of the various dyes.

[0556] According to a preferred embodiment, the switching layer comprises one or more dichroic dyes that absorb light in the red and NIR regions, i.e., in the wavelength range of 600 nm to 2000 nm, preferably in the range of 600 nm to 1800 nm, and particularly preferably in the wavelength range of 650 nm to 1300 nm.

[0557] In a preferred embodiment, in addition to the compound of Formula I, the mesocrystalline medium further contains at least one dichroic dye. Preferably, one or more such dichroic dyes are selected from azo dyes, anthraquinones, methine compounds, azo-methimazole compounds, anthocyanin compounds, naphthoquinones, tetraazines, perylene, terrylene, quaterrylene, higher terrylene, pyrrolemethylbenzene, thiadiazoles, benzothiadiazoles, nickel dithiolenes, (metallic) phthalocyanines, (metallic) naphthylphthalocyanines, and (metallic) porphyrins. Among these, azo dyes, thiadiazoles, and benzothiadiazoles are particularly preferred.

[0558] In one embodiment, the preferred alternative dichroic dyes in the switching layer having a structure different from Formula I are preferably selected from the dye classes indicated in Chapter 11.2.1 of B. Bahadur, Liquid Crystals - Applications and Uses, Vol. 3, 1992, World Scientific Publishing, and particularly preferably from the specific compounds given in the table presented therein.

[0559] The dye belongs to the category of dichroic dyes known in the art and described in the references. Therefore, for example, anthraquinone dyes are described in EP 34832, EP 44893, EP 48583, EP 54217, EP 56492, EP 59036, GB 2065158, GB 2065695, GB 2081736, GB 2082196, GB 2094822, GB 2094825, JP-A 55-123673, DE 3017877, DE 3040102, DE 3115147, DE 3115762, DE 3150803 and DE 3201120, naphthoquinone dyes are described in DE 3126108 and DE 3202761, and azo dyes are described in EP 43904, DE 3201120, JP-A 55-123673, DE 3017877, DE 3040102, DE 3115147, DE 3115762, DE 3150803 and ... 3123519, WO82 / 2054, GB 2079770, JP-A 56-57850, JP-A 56-104984, US 4308161, US 4308162, US4340973, T. Uchida, C. Shishido, H. Seki and M. Wada: Mol. Cryst. Lig. Cryst. 39,39-52 (1977), and H. Seki, C. Shishido, S. Yasui and T. Uchida: Jpn. J. Appl. Phys.21, 191-192 (1982), and Perylene is described in EP 60895, EP 68427 and WO 82 / 1191. Rye dyes are described, for example, in EP 2166040, US 2011 / 0042651, EP 68427, EP 47027, EP 60895, DE 3110960 and EP 698649.

[0560] Examples of other preferred dichroic dyes that may be present in the switching layer of the device are shown below.

[0561]

[0562] In a particularly preferred embodiment, the mesocrystalline medium further comprises at least one compound selected from the group consisting of compounds of the following formula:

[0563]

[0564]

[0565]

[0566]

[0567] In one specific embodiment, the medium according to the invention comprises one or more quencher compounds. It is preferred if the device according to the invention comprises one or more fluorescent dyes in the switching layer.

[0568] Quenching compounds are compounds that quench fluorescence. These quenching compounds absorb the electronic excitation energy of adjacent molecules (such as fluorescent dyes) in the switching layer and undergo a transition to an electronically excited state in the process. The fluorescent dye to be quenched is thus converted to its electronic ground state and prevented from emitting fluorescence or undergoing subsequent reactions. The quenching compound itself is deactivated without radiation or recovers to its ground state by emitting light and can be reused for further quenching.

[0569] The quencher compound can have various functions in the medium and switching layer of the device according to the invention. First, the quencher compound can help extend the lifetime of the dye system by deactivating the electronic excitation energy. Second, the quencher compound can eliminate other aesthetically undesirable color effects, such as colored emission emitted by fluorescent dyes in the switching layer in the internal space.

[0570] To achieve effective quenching, the quenching compound should be suitable for the corresponding dye system, especially the dyes in the dye composition that absorb at the longest wavelength. Methods for implementing this approach are known in the art.

[0571] Preferred quencher compounds are described, for example, in Table 8.1 on page 279 of JR Lakowicz, Principles of Fluorescence Spectroscopy, 3rd edition, 2010, ISBN 10: 0-387-31278-1, Springer Science + Business Media LLC. Other classes of compounds, such as so-called dark quenchers or black hole quenchers, are known in the art. Examples include azo dyes and aminoanthraquinones. The quencher compound used in the switching layer of the device according to the invention may also be a non-fluorescent dye or a dye that fluoresces only in NIR.

[0572] In a preferred embodiment of the switching layer according to the invention, any quencher compound present is selected such that fluorescence in the visible portion of the spectrum is suppressed.

[0573] The device according to the invention is preferably suitable for regulating energy in the form of sunlight as it flows from the environment into an interior space. Here, the energy to be regulated flows from the environment (i.e., the external space) into the interior space.

[0574] The interior space here can be any desired space that is essentially isolated from the environment, such as a building, vehicle, or container.

[0575] Therefore, the present invention also relates to the use of a device for regulating the flow of energy through an external space into an internal space.

[0576] However, the device can also be used in interior aesthetic design, for example, for light and color effects. For instance, door and wall elements containing gray or colored components according to the device can be switched to transparent. Furthermore, the device may also include a white or colored flat panel backlight for adjusting brightness, or a yellow flat panel backlight for adjusting color via a blue subject-object display. In cases where a glass substrate is used in the device, one or both sides of the glass in the device according to the invention may be equipped with roughened or structured glass for light coupling output and / or for generating light effects.

[0577] Therefore, the liquid crystal medium according to the invention is preferably used in building windows or automobiles, such as sunroofs. Specifically, the switchable optics can be included in the windows or facades of a building. The device according to the invention is also applicable to commercial vehicles, ships, trains, or airplanes.

[0578] In another alternative application, the device is used to regulate the light incident on the eye, such as in goggles, visors, or sunglasses, wherein the device maintains a low level of light incident on the eye in one switching state and reduces the light incident to a smaller level in another switching state.

[0579] The device according to the invention is preferably arranged in an opening of a relatively large two-dimensional structure, wherein the two-dimensional structure itself allows only slight or no energy passage, and wherein the opening has a relatively high energy transmittance. The two-dimensional structure is preferably a wall or another boundary between the interior space and the exterior. Furthermore, the two-dimensional structure preferably covers an area of ​​at least equal size, particularly preferably at least twice the size of the area in which the opening according to the invention is disposed.

[0580] The preferred feature of the device is that it has a diameter of at least 0.05 m. 2 Preferably at least 0.1 m 2 Preferably at least 0.5 m 2 And very particularly preferred at least 1.0 m 2 The area of ​​the device. For a window containing the device, the area of ​​the device is preferably 0.1 m². 2 Up to 10m 2 More preferably 0.5 m 2 up to 5 m 2 , and especially 1 m 2 up to 3 m 2 Within the range.

[0581] The device is preferably housed in an opening with relatively high energy transmittance, as described above, in a building, container, vehicle, or other substantially enclosed space. The device can generally be used in any desired interior space, particularly if it has only limited air exchange with the environment and a light-transmitting boundary surface through which energy can be input from the outside in the form of light. Use of the device is particularly preferred for interior spaces exposed to strong sunlight through light-transmitting areas (e.g., through window areas).

[0582] The device according to the invention is switchable. Here, switching refers to a change in the energy passing through the device. The device according to the invention is preferably electrically switchable, as described, for example, in WO 2009 / 141295 and WO 2014 / 090373.

[0583] However, the device can also be thermally switchable, as described, for example, in WO 2010 / 118422. In this case, the switching is preferably performed by changing the temperature of the switching layer comprising the compound of formula I and the liquid crystal medium from a nematic state to an isotropic state. In the nematic state, the molecules of the liquid crystal medium are ordered, and therefore the compound of formula I is also ordered, for example, aligned parallel to the surface of the device by the action of the alignment layer. In the isotropic state, the molecules are disordered, and therefore the compound of formula I is also disordered. Based on the principle that dichroic compounds have higher or lower absorption coefficients depending on their alignment with the polarization plane of light, the difference between the ordered and disordered states of the dichroic compounds causes a difference in the transmittance of the switching layer of the device according to the invention.

[0584] In the case of an electrically switchable device, it preferably comprises two or more electrodes, which are preferably mounted on both sides of the switching layer. These electrodes are preferably composed of ITO or a thin, preferably transparent layer of metal and / or metal oxide, such as silver or FTO (fluorine-doped tin oxide) or alternative materials known in the art for this purpose. The electrodes are preferably electrically connected. The voltage is preferably provided by a battery, a rechargeable battery, or an external power source, particularly an external power source.

[0585] In the case of electrical switching, the switching operation is performed by applying a voltage to (re)orient the molecules of the liquid crystal medium.

[0586] In one embodiment, the device transitions from a state with high absorption (i.e., low transmittance) existing under no-voltage conditions to a state with lower absorption (i.e., higher transmittance). The liquid crystal medium of the switching layer is preferably nematic in both states. The no-voltage state is preferably characterized by the molecules of the liquid crystal medium (and therefore the molecules of compound I) being aligned parallel to the plane of the switching layer. This is preferably achieved by a correspondingly selected alignment layer. The voltage-applied state is preferably characterized by the molecules of the liquid crystal medium (and therefore the molecules of compound I) being perpendicular to the plane of the switching layer.

[0587] In one alternative embodiment, the device can switch from a state with low absorption (i.e., high transmittance) existing in the absence of voltage to a state with higher absorption (i.e., lower transmittance). The liquid crystal medium of the switching layer is preferably nematic in both states. The absence of voltage is preferably characterized in that the molecules of the liquid crystal medium of the switching layer (and therefore the molecules of compound I) are aligned perpendicular to the plane of the switching layer. This is preferably achieved by a correspondingly selected alignment layer. The applied voltage state is preferably characterized in that the molecules of the liquid crystal medium of the switching layer (and therefore the molecules of compound I) are parallel to the plane of the switching layer.

[0588] The device according to the invention preferably has the following layer order, wherein other layers may also exist. The layers indicated below are preferably directly adjacent to each other in the device:

[0589] - The substrate layer, preferably comprising glass or polymer.

[0590] - Conductive transparent layer, preferably containing ITO

[0591] - Alignment layer

[0592] - A switching layer containing one or more compounds of formula I.

[0593] - Alignment layer

[0594] - Conductive transparent layer, preferably containing ITO

[0595] - The base layer, preferably comprising glass or polymer.

[0596] In another embodiment, the device contains two switching layers, which can be arranged in a so-called dual-box.

[0597] The device according to the invention preferably comprises one or more (particularly preferred, two) alignment layers. The alignment layers are preferably directly adjacent to both sides of the switching layer comprising the compound of formula I.

[0598] The alignment layer used in the device according to the invention can be any layer desired for this purpose known to those skilled in the art. A polyimide layer is preferred, and a layer comprising rubbed polyimide is particularly preferred. In one embodiment, planar alignment is provided, wherein a slight pretilt angle is more preferably set. In an alternative embodiment, vertical alignment is provided, wherein a high pretilt angle is more preferably set.

[0599] Furthermore, polymers obtained by exposure methods involving polarized light can be used as alignment layers to achieve the alignment of liquid crystal media compounds according to alignment axes (i.e., photoalignment).

[0600] In the device according to the invention, the switching layer is more preferably disposed between or thereby enclosed between two substrate layers. The substrate is preferably optically transparent. The substrate layer may, for example, be composed of glass or a polymer (preferably a light-transmitting polymer).

[0601] Suitable glass substrates include, for example, float glass, down-drawn glass, chemically or heat-treated tempered glass, borosilicate glass, and aluminosilicate glass.

[0602] Suitable polymer substrates include, for example, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyvinyl butyral (PVB), polymethyl methacrylate (PMMA), polycarbonate (PC), polyimide (PI), COP (cyclic olefin polymer), and cellulose triacetate (TAC).

[0603] Two substrates are arranged in a box, with a gap formed between them. The size of this gap, or the corresponding thickness of the switching layer, is preferably from 1 µm to 100 µm, more preferably from 2 µm to 50 µm, and more preferably from 3 µm to 25 µm, and most preferably from 5 µm to 10 µm. The box is typically sealed by means of adhesive tape located at or near the edges. In a preferred embodiment, the box gap is 25 µm or less, preferably 10 µm or less, and more preferably 6 µm or less.

[0604] The device is preferably characterized in that it does not contain a polymer-based polarizer, particularly preferably does not contain a polarizer in a solid material phase, and very particularly preferably does not contain a polarizer at all.

[0605] However, according to an alternative embodiment, the device may also include one or more polarizers. In this case, the polarizer is preferably a linear polarizer.

[0606] If a polarizer is present, its absorption direction is preferably perpendicular to the orientation axis of the liquid crystal medium compound on the side of the switching layer where the polarizer is located, according to the device of the invention.

[0607] In the device according to the invention, both absorptive and reflective polarizers may be optionally employed. Polarizers in the form of thin optical films are preferred. Examples of reflective polarizers that can be used in the device according to the invention are DRPF (diffuse reflective polarizer film, 3M), DBEF (dual brightness enhancement film, 3M), DBR (layered polymer distributed Bragg reflector, as described in US 7,038,745 and US 6,099,758), and APF (advanced polarizer film, 3M, see Technical Digest SID 2006, 45.1, US 2011 / 0043732 and US 7,023,602). Additionally, wire grating polarizers (WGP, wire grating polarizer) based on reflected infrared light can be employed. Examples of absorptive polarizers that may optionally be used in the device according to the invention are Itos XP38 polarizer film and Nitto Denko GU-1220DUN polarizer film. One example of a circular polarizer that can be used according to the present invention is the APNCP37-035-STD polarizer (American Polarizers). Another example is the CP42 polarizer (ITOS).

[0608] In a preferred embodiment, the device according to the invention is a component of a window, more preferably a window assembly comprising at least one glass surface, and particularly preferably an assembly of an insulated glass unit.

[0609] The window here preferably refers to a structure, particularly in a building, comprising a frame and at least one glass pane surrounding the frame. It preferably comprises an insulated frame and two or more glass panes, i.e., multi-pane insulated glass.

[0610] According to a preferred embodiment, the device according to the invention is applied directly to the glass surface of a window, particularly preferably to the gap between two glass panes of a multi-pane insulated glass.

[0611] Furthermore, the present invention relates to a window comprising a device according to the invention, preferably having the preferred features indicated above.

[0612] Due to the electronic properties of the compounds according to the invention, these compounds are suitable for use as organic semiconductors in addition to their use as dyes.

[0613] Therefore, the present invention also relates to the use of compounds of formula I in organic electronic components such as, for example, organic light-emitting diodes (OLEDs), organic field-effect transistors (OFETs), printed circuits, radio frequency identification elements (RFID), lighting elements, photovoltaic devices, and optical sensors.

[0614] Due to their colored properties and good solubility in organic materials, the compounds according to the present invention are extremely suitable as dyes.

[0615] Therefore, the present invention also relates to the use of Formula I dyes in coloring polymers.

[0616] In this invention and particularly in the following examples, the structure of the mesocrystalline compound is represented by abbreviations (also known as acronyms). In such acronyms, the chemical formula uses the abbreviations listed in Tables A to C below. All groups C n H 2n+1 C m H 2m+1 and C l H 2l+1 Or C n H 2n-1 C m H 2m-1 and C l H 2l-1 The acronym represents a straight-chain alkyl or alkenyl group, preferably 1E-alkenyl, each having n, m, and l carbon atoms, respectively. Table A lists the codes for the ring elements used in the core structure of the compound, while Table B shows the linking groups. Table C gives the meaning of the codes used for the left or right end groups. The acronym consists of the following: the code for the ring element with an optional linking group, followed by the first hyphen and the code for the left end group, and the second hyphen and the code for the right end group. Table D shows the illustrative structure of the compound along with its corresponding abbreviation.

[0617] Table A: Ring Elements

[0618]

[0619]

[0620]

[0621] Table B: Connecting Bases

[0622]

[0623] Table C: End groups

[0624] Where n and m each represent integers, and the three dots "..." are placeholders for other abbreviations from this table.

[0625] The table below shows illustrative structures along with their corresponding abbreviations. These are shown to explain the meaning of the rules used for these abbreviations. They also indicate the preferred compounds.

[0626] Table D: Explanatory Structure

[0627]

[0628]

[0629]

[0630]

[0631]

[0632]

[0633]

[0634]

[0635]

[0636]

[0637]

[0638]

[0639]

[0640]

[0641]

[0642]

[0643]

[0644]

[0645]

[0646]

[0647] Where n, m, and l preferably represent 1 to 7 independently of each other.

[0648] Table E below shows illustrative compounds that can be optionally used as stabilizers in mesocrystalline media according to the present invention.

[0649] Table E

[0650] Table E shows possible stabilizers that can be added to the LC media according to the invention, where n represents an integer from 1 to 12, preferably 1, 2, 3, 4, 5, 6, 7 or 8.

[0651]

[0652]

[0653]

[0654]

[0655]

[0656]

[0657]

[0658] The LC medium preferably contains 0 to 10% by weight, particularly 1 ppm to 5% by weight, and especially preferably 1 ppm to 1% by weight of stabilizer.

[0659] Table F below shows illustrative compounds that can be preferably used as chiral dopants in mesocrystalline media according to the present invention.

[0660] Table F

[0661]

[0662]

[0663]

[0664] In a preferred embodiment of the invention, the mesocrystalline medium comprises one or more compounds selected from the group consisting of compounds from Table F.

[0665] The mesocrystalline medium according to the invention preferably comprises two or more, more preferably four or more compounds selected from the group consisting of compounds from D, E and F in the table above.

[0666] The liquid crystal medium according to the invention preferably comprises seven or more, more preferably eight or more individual compounds selected from the group of compounds from Table D, more preferably three or more, and particularly preferably four or more compounds having different formulas selected from those shown in Table D.

[0667] The LC medium according to the invention may also contain compounds in which, for example, H, C, N, O, Cl, or F has been replaced by the corresponding isotopes.

[0668] Unless otherwise explicitly stated, all percentage data and ratios given in this document are weight percentages.

[0669] Unless otherwise explicitly indicated, all physical properties were determined according to "Merck Liquid Crystals, Physical Properties of Liquid Crystals", Status Nov. 1997, Merck KGaA, Germany, and are applicable to a temperature of 20°C. Unless otherwise indicated, the value of Δn in each case was determined at 589 nm, and the value of Δε was determined at 1 kHz. e and n o In each case, the refractive index of the anomalous and ordinary beams under the conditions indicated above.

[0670] The degree of anisotropy R is determined by the extinction coefficients E(p) (the extinction coefficient of the mixture when the molecules are aligned parallel to the polarization direction of the light) and E(s) (the extinction coefficient of the mixture when the molecules are aligned perpendicular to the polarization direction of the light), in each case at the maximum wavelength of the absorption band of the dye of interest. If the dye has multiple absorption bands, the strongest absorption band is usually selected. As is known in the art, the alignment of the molecules in the mixture is achieved by an alignment layer. To eliminate the influence of the liquid crystal medium, other absorptions, or reflections, each measurement is performed on the same mixture without the dye, and the obtained value is subtracted.

[0671] Measurements are performed using linearly polarized light whose vibration direction is parallel to the alignment direction (for the determination of E(p)) or perpendicular to the alignment direction (for the determination of E(s)). This can be achieved using a linear polarizer, which is rotated relative to the apparatus to achieve two different polarization directions. Therefore, the measurements of E(p) and E(s) are performed via rotation of the polarization direction of the incident polarized light.

[0672] The degree of anisotropy R is calculated from the combined value of E(s) and E(p) according to the following formula:

[0673]

[0674] As indicated in this article, particularly in "Polarized Light in Optics and Spectroscopy," DSKliger et al., Academic Press, 1990. A detailed description of the method for determining the degree of anisotropy of liquid crystal media containing dichroic dyes can also be found in B. Bahadur, Liquid Crystals - Applications and Uses, Vol. 3, 1992, World Scientific Publishing, Section 11.4.2.

[0675] Isotropic extinction coefficient E iso The combined value of E(s) and E(p) is calculated according to the following formula:

[0676] .

[0677] In this article, ε is used iso The isotropic extinction coefficient is calculated according to the following formula:

[0678] ,

[0679] Where c is the dye concentration, specifically given in weight % and d is the measured thickness of the guest-host medium layer, specifically given in cm.

[0680] The following examples are merely illustrative of the invention and should not be construed as limiting the scope of the invention in any way. These examples, modifications, or other equivalents will become apparent to those skilled in the art based on this disclosure. Detailed Implementation

[0681] Example

[0682] In an embodiment,

[0683] V o The threshold voltage and capacitance [V] represent the capacitance at 20°C.

[0684] n e This indicates the unusual refractive index at 20°C and 589 nm.

[0685] n o This represents the ordinary refractive index at 20°C and 589 nm.

[0686] Δn represents the optical anisotropy at 20℃ and 589 nm.

[0687] ε ∥ This represents the dielectric constant parallel to the director at 20℃ and 1 kHz.

[0688] ε ⊥ This represents the dielectric constant perpendicular to the director at 20°C and 1 kHz.

[0689] Δε represents the dielectric anisotropy at 20 °C and 1 kHz.

[0690] cl.p., T(N,I) represents the clearing point [°C].

[0691] γ1 represents the rotational viscosity [mPa·s] measured at 20°C, determined by rotation in a magnetic field.

[0692] K1 represents the elastic constant, and the "bending" deformation [pN] at 20℃.

[0693] K2 represents the elastic constant, and the "torsional" deformation [pN] at 20℃.

[0694] K3 represents the elastic constant, the bending deformation [pN] at 20℃.

[0695] Unless otherwise explicitly indicated, the term "threshold voltage" in this invention refers to the capacitance threshold (V0). In embodiments, as is generally the case, it may also indicate 10% relative contrast (V0). 10 The optical threshold of ).

[0696] Synthesis Examples

[0697] Synthesis Example 1

[0698] Preparation of Compound 1

[0699]

[0700] Step 1:

[0701]

[0702] 4,5-Bis(2-ethylhexyl)-dithieno[2,3-d:2',3'-d']thieno[3,2-b:4,5-b']dipyrrole was obtained according to Chung, Chin-Lung et al., Organic Electronics 2018, 18, 6-16. Aluminum chloride (0.48 g, 3.60 mmol) was added to a stirred solution of 4,5-bis(2-ethylhexyl)-dithieno[2,3-d:2',3'-d']thieno[3,2-b:4,5-b']dipyrrole (0.60 g, 1.20 mmol) and heptanyl chloride (0.36 g, 2.40 mmol) in dichloromethane (6 mL) at room temperature. After stirring at this temperature for 18 h, the resulting red solution was carefully added to cooled HCl solution (2N) and extracted with dichloromethane. The combined organic phases were dried over sodium sulfate. Final purification was performed by column chromatography (silica gel; heptane / DCM: 9 / 1) to yield a ketone product as a red oil. EI-MS: m / z: 610.3.

[0703] Step 2:

[0704]

[0705] A solution of N-bromosuccinimide (0.28 g, 1.57 mmol) in THF (10 mL) was added dropwise to a stirred solution of the ketone obtained in step 1 (1.00 g, 1.64 mmol) in THF (10 mL) at 0 °C under light-protected conditions. The resulting solution was heated to room temperature and stirred at this temperature for 2 h. Purification was performed by column chromatography (silica gel; heptane / DCM: 9 / 1) to yield a bromo-ketone product as a red solid. This compound was used directly in the next step without further purification.

[0706] Step 3:

[0707]

[0708] N,N-Dihexyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborpentan-2-yl)aniline was obtained according to Chung, Bures et al., Sci. Pap. Univ. Pardubice, Ser. A 2014, 20, 247-259. Pd(OAc)2 (18.4 mg, 0.08 mmol), Sphos (69.4 mg, 0.16 mmol), the bromo-ketone product obtained in step 2 (1.13 g, 1.64 mmol), K3PO4 (1.05 g, 4.94 mmol), and N,N,-Dihexyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborpentan-2-yl)aniline (1.03 g, 2.46 mmol) were dissolved in THF (10 mL) and water (2 mL). The resulting mixture was heated to 65 °C and stirred at this temperature for 18 h. The reaction mixture was extracted with dichloromethane. The combined organic phases were dried over MgSO4 and filtered off. Final purification was performed by column chromatography (reversed phase; acetonitrile / THF) to yield compound 1, which was a red oil.

[0709] 1H-NMR (pyridine-d5, 700 MHz): δ = 8.35 (s, 1H), 7.82 (d, J = 8.0 Hz, 2H), 7.71 (s, 1H), 6.85 (d, J = 8.0 Hz, 2H), 4.59 - 4.46 (m, 4H), 3.32 - 3.29 (m,4H), 3.03 - 3.01 (m, 2H), 2.25 - 2.20 (m, 2H), 1.84 - 1.80 (m, 2H), 1.60 -1.57 (m, 4H), 1.34 - 1.25 (m, 24H), 1.19 - 1.10 (m, 10H), 0.87 - 0.75 (m,21H).

[0710] APCI-MS: m / z: 870.5.

[0711] Compound 1 shows the results obtained in the main mixture H-1 as described below, at λ max =470 nm and 750 (wt% * cm) -1 The isotropic extinction coefficient ε iso The maximum absorption value below.

[0712] Synthesis Example 2

[0713] Preparation of compound 2

[0714]

[0715] Step 1:

[0716]

[0717] Aluminum chloride (1.60 g, 12.03 mmol) was added to a stirred solution of 4,5-bis(2-ethylhexyl)-dithieno[2,3-d:2',3'-d']thieno[3,2-b:4,5-b']dipyrrole (1.00 g, 2.00 mmol) and 2-ethylhexanoyl chloride (1.30 g, 7.99 mmol) in dichloromethane (10 mL) at room temperature. After stirring at this temperature for 18 h, the resulting red solution was carefully added to cooled HCl solution (6N) and extracted with dichloromethane. The combined organic phases were dried over sodium sulfate. Final purification was performed by column chromatography (silica gel; DCM) and recrystallization from DCM / MeOH: 2 / 5 to yield a ketone product as a red oil. APCI-MS: m / z: 625.3.

[0718] Step 2:

[0719] A solution of N-bromosuccinimide (0.19 g, 1.12 mmol) in THF (3 mL) was added dropwise to a stirred solution of the ketone product obtained in step 1 (0.70 g, 0.64 mmol) in THF (3 mL) at 0 °C under light-protected conditions. The resulting solution was heated to room temperature and stirred at this temperature for 2 h. Purification was performed by column chromatography (silica gel; DCM) to yield a bromo-ketone product as a red solid. This compound was used directly in the next step without further purification.

[0720] Step 3:

[0721] Pd(OAc)₂ (11.5 mg, 0.05 mmol), SPhos (43.4 mg, 0.10 mmol), the bromo-ketone product obtained in step 2 (0.85 g, 1.21 mmol, HPLC: 85%), K₃PO₄ (0.65 g, 3.09 mmol), and N,N,-dihexyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborpentan-2-yl)aniline (0.60 g, 1.55 mmol) were dissolved in THF (7 mL) and water (2 mL). The resulting mixture was heated to 65 °C and stirred at this temperature for 3 days. The reaction mixture was extracted with dichloromethane. The combined organic phases were dried over MgSO₄ and filtered off. Final purification was performed by column chromatography (reversed phase; acetonitrile / THF) to yield compound 2, which was a red oil.

[0722] 1 H-NMR (CDCl3, 700 MHz): δ = 7.64 (s, 1H), 7.48 (d, J = 8.4 Hz, 2H), 7.02 (s, 1H), 6.65 (d, J = 8.5 Hz, 2H), 4.33 - 4.21 (m, 4H), 3.31 - 3.27 (m,4H), 3.11 - 3.09 (m, 1H), 2.04 - 1.97 (m, 2H), 1.86 - 1.80 (m, 2H), 1.63 -1.52 (m, 7H), 1.36 - 1.29 (m, 13H), 1.28 - 1.12 (m,18H), 0.94 - 0.78 (m,24H).

[0723] APCI-MS: m / z: 884.5.

[0724] Compound 2 showed the same λ as determined in the main mixture H-1 given below. max = 470 nm and 715 (wt% * cm) -1 The isotropic extinction coefficient ε iso The maximum absorption value below.

[0725] Synthesis Example 3

[0726] Preparation of compound 3

[0727]

[0728] Compound 1 (100 mg, 0.11 mmol), prepared as in Synthetic Example 1, malononitrile (2.28 g, 34.45 mmol), and lithium-bis(trimethyl)azanide (0.96 g, 5.58 mmol) were dissolved in 1,2-dichloroethane (3 mL) and stirred at 80 °C for 18 h. Water (100 mL) and DCM (100 mL) were added to the cooled reaction mixture. The phases were separated and the organic phase was washed several times with water. The solvent was removed and the resulting solid was dissolved in DCM and precipitated by adding MeOH. Final purification was performed by column chromatography (silica gel; heptane / toluene: 1 / 1) to yield compound 3 as a blue solid.

[0729] 1 H-NMR (CDCl3, 700 MHz): δ = 8.16 (s, 1H), 7.49 (d, J = 8.7 Hz, 2H), 7.01 (s, 1H), 6.65 (d, J = 8.7 Hz, 2H), 4.33 - 4.21 (m, 4H), 3.32 - 3.29 (m,4H), 2.94 -2.90 (m, 2H), 2.02 - 1.97 (m, 2H), 1.81 - 1.75 (m, 2H), 1.64 -1.61 (m, 4H), 1.51 - 1.48 (m, 2H), 1.37 - 1.32 (m,16H), 1.28 - 1.15 (m,16H), 0.93 - 0.89 (m, 9H), 0.87 - 0.78 (m, 12H).

[0730] APCI-MS: m / z: 918.5.

[0731] Compound 3 showed the same λ as determined in the main mixture H-1 given below. max= 602 nm and 880 (wt% * cm) -1 The isotropic extinction coefficient ε iso The maximum absorption value below.

[0732] Synthesis Example 4

[0733] Preparation of compound 4

[0734]

[0735] Step 1:

[0736] N-BuLi (1.38 mL, 2.21 mmol, 1.6 M in hexane) was added dropwise to a stirred solution of 4,5-bis(2-ethylhexyl)-dithieno[2,3-d:2',3'-d']thieno[3,2-b:4,5-b']dipyrrole (1.09 g, 2.18 mmol) in THF (15 mL) at -78 °C. After stirring at this temperature for 1 h, the resulting red solution was heated to room temperature and CO2 gas was bubbled through the solution for 1 h. HCl (2 M) and ethyl acetate were added. The organic phase was separated and dried over sodium sulfate. Final purification was performed by recrystallization from n-heptane to yield a carboxylic acid product as a red solid.

[0737] 1 H-NMR (CDCl3, 400 MHz): δ = 7.80 (s, 2H), 7.16 (d, J = 5.2 Hz, 1H), 7.00 (d, J = 5.2 Hz, 1H), 4.47 - 4.10 (m, 4H), 2.00 (m, 2H), 1.28 - 1.19 (m,16H), 0.84 - 0.77 (m, 12H).

[0738] EI-MS: m / z: 542.4.

[0739] Step 2:

[0740]

[0741] A solution of ({[3-(dimethylamino)propyl]imino}methylene)(ethyl)amine (0.38 g, 2.45 mmol) in toluene (1 mL) was added dropwise to the carboxylic acid product (1.10 g, 2.02 mmol) obtained in step 1 in toluene (5.5 mL) at 0 °C. The resulting solution was heated to room temperature and stirred at this temperature for 16 h. Oxalic acid (53 mg, 0.40 mmol) was added and stirred for 1 h. Purification was performed by column chromatography (silica gel; toluene) to yield the carboxylic acid ester product as a red oil. This compound was used directly in the next step without further purification.

[0742] Step 3:

[0743] A solution of N-bromosuccinimide (275 mg, 1.54 mmol) in THF (21 mL) was added to the carboxylic acid ester product (1.00 g, 1.47 mmol) obtained in step 2 in THF (72 mL) under light-protected conditions at 0 °C. The solution was stirred at this temperature for another 30 min, and then the mixture was allowed to warm to room temperature overnight. Purification was performed by column chromatography (silica gel; THF) to yield the bromo-carboxylic acid ester product as a red solid (APCI-MS: m / z: 758.1). This compound was used directly in the next step without further purification.

[0744] Step 4:

[0745]

[0746] A solution of N,N-dihexyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborpentan-2-yl)aniline (0.68 g, 1.65 mmol) in toluene (6 mL) was slowly added to a mixture of Pd2dba3 (5.1 mg, 0.01 mmol), P(o-tol)3 (6.8 mg, 0.02 mmol), and the bromo-carboxylic acid ester product obtained in step 3 (0.53 g, 0.56 mmol, HPLC: 80%) in toluene (11 mL) and Na2CO3 aqueous solution (2.2 mL, 2 M). The resulting mixture was stirred at 100 °C for 18 h, then a mixture of Pd₂dba₃ (3.6 mg, 0.01 mmol), P(o-tol)₃ (6.6 mg, 0.02 mmol), toluene (3 mL), and Na₂CO₃ aqueous solution (1.2 mL, 2 M) was added, and the mixture was stirred again at 100 °C for 18 h. Water (30 mL) and MTBE (30 mL) were added to the cooled reaction mixture. The phases were separated and the aqueous phase was extracted several times with MTBE. The combined organic phases were dried over sodium sulfate and filtered off. Final purification was performed by column chromatography (reversed phase; acetonitrile / THF) and recrystallized from heptane / toluene: 2 / 1 to give compound 4 as an orange solid.

[0747] 1 H-NMR (CDCl3, 500 MHz): δ = 7.84 (s, 1H), 7.48 - 4.46 (m, 2H), 7.13 -7.11 (m, 2H), 7.02 (s, 1H), 6.67 - 6.65 (m, 2H), 4.36 - 4.21 (m, 4H), 3.31 -3.27 (m, 4H), 2.02 - 2.00 (m, 2H), 2.04 - 1.97 (m, 2H), 1.62 - 1.60 (m, 4H), 1.34 - 1.18 (m, 28H), 0.93 - 0.90 (m, 6H), 0.84 - 0.80 (m, 12H).

[0748] APCI-MS: m / z: 939.5.

[0749] Compound 4 showed the same activity as determined in the main mixture H-1 given below at λ max = 485 nm and 695 (wt% * cm) -1 The isotropic extinction coefficient ε iso The maximum absorption value is given below. The degree of anisotropy R, as measured in the main mixture H-1 given below, is 0.70.

[0750] Synthetic Examples 5, 6, 7, 8 and 9

[0751] Similar to the synthesis examples 1 to 4 above, the following compounds 5, 6, 7, 8 and 9 were prepared and their physical properties were characterized.

[0752] Compound 5

[0753]

[0754] Compound 5 showed the same λ as determined in the main mixture H-1 given below. max = 721 nm and 840 (wt% * cm) -1 The isotropic extinction coefficient ε iso The maximum absorption value below.

[0755] Compound 6

[0756]

[0757] Compound 6 showed the same λ as determined in the main mixture H-1 given below. max = 473 nm and 675 (wt% * cm) -1 The isotropic extinction coefficient ε iso The maximum absorption value is given below. The degree of anisotropy R, as measured in the main mixture H-1 given below, is 0.71.

[0758] Compound 7

[0759]

[0760] Compound 7 showed the same λ as determined in the main mixture H-1 given below. max = 598 nm and 685 (wt% * cm) -1 The isotropic extinction coefficient ε iso The maximum absorption value below.

[0761] Compound 8

[0762]

[0763] Compound 9

[0764]

[0765] Mixture Examples and Comparative Mixture Examples

[0766] Comparative Mixture Example 1

[0767] Liquid crystal bulk mixture H-1 was prepared and its general physical properties were characterized, having the composition and properties indicated in the table below.

[0768] The comparative mixture CM-1 was prepared by mixing the following: 96.621% mixture H-1 and 0.100% of the following compound.

[0769] (Hereinafter referred to as ST-1), 0.100% of the following compound:

[0770] (Hereinafter referred to as ST-2), 0.127% of compound R-5011 as described in Table F above, and 0.476% of the following compound,

[0771] (Hereinafter referred to as D-A1), 1.246% of the following compound:

[0772] (Hereinafter referred to as D-A2) and 1.330% of the following compound:

[0773] (It will be referred to as D-A3 below).

[0774] Comparative Mixture Example 2

[0775] Liquid crystal bulk mixture H-2 was prepared and its general physical properties were characterized, having the composition and properties indicated in the table below.

[0776] The comparative mixture CM-2 was prepared by mixing the following: 90.68% mixture H-2 and 0.10% compound ST-1, and 1.05% of the following compound.

[0777] (Hereinafter referred to as D-B1), 1.63% of the following compound:

[0778] (Hereinafter referred to as D-B2), 2.10% of the following compound:

[0779] (Hereinafter referred to as D-B3), 1.64% of the following compound:

[0780] (Hereinafter referred to as D-B4), 0.60% of the following compound:

[0781] (Hereinafter referred to as D-B5) and 2.20% of the following compound:

[0782] (It will be referred to as D-B6 below).

[0783] The comparative mixture CM-2.1 was prepared by mixing the following: 99.847% of the mixture CM-2 as described in Table F above and 0.153% of compound R-5011.

[0784] The comparative mixture CM-2.2 was prepared by mixing the following: 99.673% of the mixture CM-2 as described in Table F above and 0.327% of compound R-5011.

[0785] Comparative Mixture Example 3

[0786] The comparative mixture CM-3 was prepared by mixing the following: 94.22% of mixture H-2 as described in Table F above, and 0.10% of compound ST-1, 0.10% of compound ST-2, 0.83% of compound D-A1, 1.00% of compound D-A2, 1.57% of compound D-A3 and 2.18% of compound S-811.

[0787] Comparative Mixture Example 4

[0788] Liquid crystal bulk mixture H-3 was prepared and its general physical properties were characterized, having the composition and properties indicated in the table below.

[0789] Liquid crystal reference mixture H-3.1 was prepared by mixing the following: 99.97% mixture H-3 and 0.03% compound ST-1.

[0790] The comparative mixture CM-4 was prepared by mixing the following: 90.128% mixture H-3.1 and 1.160% compound D-B1, 1.919% compound D-B2, 1.800% compound D-B3, 1.300% compound D-B4, 0.730% compound D-B5, 2.110% compound D-B6 and 0.853% of the following compound:

[0791]

[0792] The comparison mixture CM-4.1 was prepared by mixing the following: 99.236% of mixture CM-4 and 0.764% of compound S-811 as described in Table F above.

[0793] The comparison mixture CM-4.2 was prepared by mixing the following: 98.980% of the mixture CM-4 as described in Table F above and 1.020% of compound S-811.

[0794] Mixture Examples

[0795] The suitability of the dyes prepared in Examples 1 to 7 for use in LC media and devices for regulating energy transfer was investigated.

[0796] Mixture Example 1

[0797] Mixture M-1 was prepared by adding 0.030% of compound ST-1, 0.050% of compound S-811, 0.213% of compound 1, 0.233% of compound 3 and 0.120% of compound 4 as described in Table F above to the main mixture H-1 as shown above.

[0798] Mixture M-1 was filled into TN dual-cell reactors, each with a cell thickness of 25 µm and a polyimide alignment layer with a pretilt angle of 1°. Despite using only a relatively small amount of dichroic dye, the electro-optic cells exhibited favorable contrast between the dark and bright states.

[0799] Mixture Example 2

[0800] Mixture M-2 was prepared by adding 0.030% of compound ST-1, 0.050% of compound S-811, 1.122% of compound 2, 0.600% of compound 4 and 1.500% of compound 7 as described in Table F above to the main mixture H-2 as shown above.

[0801] The mixture M-2 was filled into TN dual-cell containers, each containing a 5 µm thick cell and a polyimide alignment layer with a pretilt angle of 1°. Despite the relatively small thickness of the cells, the device exhibited favorable contrast between the dark and light states.

[0802] Mixture Example 3

[0803] Mixture M-3 was prepared by adding 0.030% of compound ST-1, 0.420% of compound 3, 0.097% of compound 4, 0.081% of compound 5 and 0.432% of compound 6 to the main mixture H-3 as shown above.

[0804] The mixture M-3 was filled into VA dual-cell chambers, each chamber having a cross geometry, a cell thickness of 15 µm, and a polyimide alignment layer with a pretilt angle of 89°. The electro-optic device exhibited favorable contrast between dark and bright states.

[0805] Mixture Example 4

[0806] Mixture M-4 was prepared by adding 0.030% of compound ST-1, 1.010% of compound S-811, 1.070% of compound 1, 1.165% of compound 3, 0.299% of compound 4 and 0.250% of compound 5 as described in Table F above to the main mixture H-3 as shown above.

[0807] The mixture M-4 was filled into a VA single cell, which had a 240° twist and an 8 µm thick polyimide alignment layer with a pretilt angle of 85°. Although the cell was only a single cell with a relatively thin switching layer, the device exhibited favorable contrast between the dark and light states.

[0808] Mixture Example 5

[0809] Mixture M-5 was prepared by adding 0.03% of compound ST-1, 2.50% of compound 1, 2.10% of compound 3, 0.57% of compound 4 and 0.48% of compound 5 to the main mixture H-3 as shown above.

[0810] The mixture M-5 was filled into a VA single cell, which was free of distortion and contained a polyimide alignment layer with a thickness of 6 µm and a pretilt angle of 89°. Although the cell was only a single cell with a relatively thin switching layer, the device exhibited suitable contrast between the dark and light states.

[0811] Mixture Example 6

[0812] Mixture M-6 was prepared by adding 0.03% of compound ST-1, 1.34% of compound S-811, 2.50% of compound 1, 2.10% of compound 3, 0.57% of compound 4 and 0.48% of compound 5 as described in Table F above to the main mixture H-3 as shown above.

[0813] The mixture M-6 was filled into a VA single cell, which had a 240° twist and a 6 µm thick polyimide alignment layer with a pretilt angle of 85°. Although the cell was only a single cell with a relatively thin switching layer, the device exhibited favorable contrast between the dark and light states.

[0814] Mixture Example 7

[0815] Mixture M-7 was prepared by adding 0.76% of compound S-811, 2.05% of compound 1, 1.80% of compound 3 and 1.02% of compound 4 as described in Table F above to the main mixture H-1 as shown above.

[0816] The mixture M-7 was filled into an STN cell containing a polyimide alignment layer with a 240° twist and a thickness of 6 µm and a pretilt angle of 5°. Although the cell is a single cell with a relatively thin switching layer, the device exhibits favorable contrast between the dark and light states.

[0817] Mixture Example 8

[0818] Mixture M-8 was prepared by adding 0.38% of compound R-5011, 2.05% of compound 1, 1.80% of compound 3 and 1.02% of compound 4 as described in Table F above to the main mixture H-1 as shown above.

[0819] The mixture M-8 was filled into a planar, highly twisted HTN cell, which has a twist of 1080° and a 6 µm thick polyimide alignment layer with a pretilt angle of 1°. Although the cell is only a single cell with a relatively thin switching layer, the device exhibits favorable contrast between dark and light states.

[0820] Mixture Example 9

[0821] Mixture M-9 was prepared by adding 0.10% of compound ST-1, 0.10% of compound ST-2, 0.23% of compound R-5011, 0.90% of compound 2, 0.31% of compound 4, 0.27% of compound 5, 0.95% of compound 6 and 2.50% of compound 7 as described in Table F above to the main mixture H-1 as shown above.

[0822] The mixture M-9 was filled into a planar, highly twisted HTN cell, wherein the cell has a twist of 1080° and a 10 µm thick polyimide alignment layer with a pretilt angle of 1°. The device exhibits favorable contrast between the dark and light states.

[0823] Mixture Example 10

[0824] Mixture M-10 was prepared by adding 0.10% of compound ST-1, 0.90% of compound 1, 1.35% of compound 3 and 1.04% of compound 4 to the main mixture H-2 as shown above.

[0825] The mixture M-10 was filled into a Heilmeier cell equipped with a linear polarizer, wherein the cell had a 5 µm thickness and a polyimide alignment layer with a pretilt angle of 1°. The device exhibited suitable contrast between the dark and bright states.

[0826] Compounds 1 to 9 and mixtures M-1 to M-10 are well-suited for regulating the flow of energy from the external space into the internal space, such as in devices that allow energy to enter through windows.

Claims

1. Compound of Formula I in R 1 and R 2 H, F, CN, N(R) may be represented in the same or different ways. z 2. A straight-chain alkyl group having 1 to 20 carbon atoms or a branched or cyclic alkyl group having 3 to 20 carbon atoms, wherein, In addition, one or more non-adjacent CH2 groups can be independently converted to -C(R) z )=C(R z )-、-C≡C-、 , , , , -N(R) z -, -O-, -S-, -CO-, -CO-O-, -O-CO-, or -O-CO-O- are replaced by O and / or S atoms that are not directly connected to each other, and among them, In addition, one or more H atoms can be replaced by F, Cl, Br, I, or CN. R z Each occurrence may represent, in the same or different ways, H, halogen, straight-chain alkyl group having 1 to 12 carbon atoms, or branched or cyclic alkyl group having 3 to 12 carbon atoms, wherein, in addition, one or more non-adjacent CH2 groups may be replaced by -O-, -S-, -CO-, -CO-O-, -O-CO-, or -O-CO-O- in such a way that the O and / or S atoms are not directly connected to each other, and wherein, in addition, one or more H atoms may be replaced by F or Cl. Q 1 and Q 2 The same or different representations of single bonds, -O-, -S-, -CF2O-, -OCF2-, -CF2-, -CF2CF2-, -CO-, -CR x1 =CR x2 -、-C≡C-、-NR x1 -, -N=N- or alicyclic or heterocyclic groups, preferably having 4 to 25 ring atoms, may also contain fused rings, and may be unsubstituted or mono- or polysubstituted with L. Z 1 and Z 2 The same or different representations of single bonds, -O-, -S-, -C(O)-, -CR y1 R y2 -, -CF2O-, -OCF2-, -C(O)-O-, -OC(O)-, -OC(O)-O-, -OCH2-, -CH2O-, -SCH2-, -CH2S-, -CF2S-, -SCF2-, -(CH2) n1 -, -CF2CH2-, -CH2CF2-, -(CF2) n1 -、-CR x1 =CR x2 -、-C≡C-、-CR x1 =CR x2 -CO-, -CO-CR x1 =CR x2 -、-CR x1 =CR x2 -COO-、-OCO-CR x1 =CR x2 -or -N=N-, R x1 R x2 Each of the following can independently represent H, F, Cl, CN, or an alkyl group having 1 to 12 carbon atoms. R y1 It represents H or an alkyl group having 1 to 12 carbon atoms. R y2 Indicates an alkyl group having 1 to 12 carbon atoms. n1 represents 1, 2, 3, or 4. A 1 and A 2 The groups, whether identical or different, representing aromatic, heteroaromatic, alicyclic, or heterocyclic groups, preferably have 4 to 25 ring atoms, and may also contain fused rings, and are either unsubstituted or monosubstituted or polysubstituted. L represents F, Cl, -CN, or a straight-chain alkyl group having 1 to 25 carbon atoms, or a branched or cyclic alkyl group having 3 to 25 carbon atoms, wherein one or more non-adjacent CH2- groups are optionally replaced by -O-, -S-, -CO-, -CO-O-, -O-CO-, or -O-CO-O- in such a way that the O atoms and / or S atoms are not directly connected to each other, and wherein one or more H atoms are each optionally replaced by F or Cl. D represents a donor group selected from a heteroaromatic group comprising at least four fused rings, wherein each ring may be unsubstituted or monosubstituted or polysubstituted by L. A represents the acceptor group. n represents 0, 1, 2, or 3, and o represents 0 or 1. The compound contains at least five rings.

2. The compound according to claim 1, wherein the acceptor group A is an electron-withdrawing group, preferably an electron-deficient portion lacking π electrons.

3. The compound according to claim 1 or 2, wherein the donor group D is a heterocyclic benzene having a linear fused ring, wherein each ring may be unsubstituted or monosubstituted or polysubstituted by L, wherein L is defined as in claim 1.

4. The compound according to one or more of claims 1 to 3, wherein: A 1 Each occurrence may represent an aryl or heteroaryl group, which may be substituted by one or more groups L as defined in claim 1, preferably 1,4-phenylene, 1,4-naphthylene, 2,6-naphthylene, thiazolyl-2,5-diyl, thiophene-2,5-diyl, thienothiophene-2,5-diyl, selenophene-2,5-diyl, thienopyrrole-2,5-diyl, dithienopyrrole diyl, dithienosylsilanecyclopentadiene diyl, cyclopentanoid dithienodiyl, pyridine-2,5-diyl, pyrimidine diyl, or pyridazine diyl, wherein one or more H atoms may be substituted by groups L as defined in claim 1, and / or Q 1 and Z 1 Indicates a single bond, and / or n represents 1 or 2, preferably 1, and / or o represents 0.

5. The compound according to one or more of claims 1 to 4, wherein the compound has a content of at least 500 (wt% * cm). -1 The isotropic extinction coefficient.

6. A mixture comprising two or more compounds according to one or more of claims 1 to 5.

7. Use of the compound according to one or more of claims 1 to 5 in a liquid crystal medium.

8. A liquid crystal medium comprising one or more compounds according to one or more of claims 1 to 5 and additionally comprising at least one mesocrystalline compound.

9. The liquid crystal medium according to claim 8, wherein the medium comprises one or more compounds selected from the group consisting of compounds of formula II-1 and II-2: in R 2 This indicates an alkyl, alkoxy, fluoroalkyl, or fluoroalkoxy group having 1 to 7 carbon atoms, or an alkenyl, alkenoxy, alkoxyalkyl, or fluoroalkenyl group having 2 to 7 carbon atoms. Optionally, one or more CH2 groups can be independently converted to carbon dioxide. , , , or Replacement and Independent of each other or , L 21 L 22 L 23 and L 24 H or F can be represented independently of each other. L 25 Indicates H or CH3, and X 2 It represents halogen, a haloalkyl or alkoxy group having 1 to 3 carbon atoms, or a haloalkenyl or alkenoxy group having 2 or 3 carbon atoms.

10. The liquid crystal medium according to claim 8 or 9, wherein the medium comprises one or more compounds selected from the group consisting of compounds of formula III and IV: in R 3 R 4 R 5 and R 6 Independently representing groups selected from: F, CF3, OCF3, CN, and straight-chain or branched alkyl or alkoxy groups having 1 to 15 carbon atoms, or straight-chain or branched alkenyl groups having 2 to 15 carbon atoms, which are unsubstituted, monosubstituted with CN or CF3, or monosubstituted or polysubstituted with halogens, and wherein one or more CH2 groups may, in each case, be independently substituted by -O-, -S-, -CO-, -COO-, -OCO-, -OCOO-, or -C≡C- in such a way that the oxygen atoms are not directly connected to each other, and L 1 L 2 L 3 L 4 and L 5 H or F can be represented independently of each other.

11. The liquid crystal medium according to one or more of claims 8 to 10, wherein the medium comprises one or more compounds selected from the group consisting of compounds of formula CY, PY, and AC: in 'a' represents 0, 1, or 2, preferably 1 or 2. b represents 0 or 1. c represents 0, 1, or 2. d represents 0 or 1. express or , and express or , express or , R 1 R 2 R AC1 and R AC2 Each of these terms independently represents an alkyl group having 1 to 12 carbon atoms, wherein... Additionally, one or two non-adjacent CH2 groups can be... , , , , -O-, -CH=CH-, -CO-, -OCO-, or -COO- are replaced by alkyl or alkoxy groups having 1 to 6 carbon atoms, in a manner in which the O atoms are not directly connected to each other. Z x Z y and Z AC Each of these independently represents -CH2CH2-, -CH=CH-, -CF2O-, -OCF2-, -CH2O-, -OCH2-, -CO-O-, -O-CO-, -C2F4-, -CF=CF-, -CH=CH-CH2O-, or a single bond, preferably a single bond. L 1-4 Each can be independently represented as F, Cl, CN, OCF3, CF3, CH3, CH2F, or CHF2, with F being the preferred one.

12. The liquid crystal medium according to one or more of claims 8 to 11, wherein the medium further comprises one or more dichroic dyes that are different from the compounds of formula I according to claims 1 to 5.

13. The liquid crystal medium according to one or more of claims 8 to 12, wherein the medium further comprises - One or more chiral compounds, preferably chiral compounds of the following formula ， More preferably, the R stereoisomer of the chiral compound, and / or - One or more stabilizers, and / or - One or more polymerizable compounds, preferably one or more polymerizable mesocrystalline compounds.

14. Use of a compound according to one or more of claims 1 to 5 or a liquid crystal medium according to one or more of claims 8 to 13, in electro-optic displays, devices for regulating energy flow through external space into internal space, electronic semiconductors, organic field-effect transistors, printed circuits, radio frequency identification elements, organic light-emitting diodes, lighting elements, photovoltaic devices, optical sensors, effect pigments, decorative elements, or as a dye for coloring polymers.

15. A device for regulating the flow of energy through an external space into an internal space, wherein the device comprises a switching layer containing a liquid crystal medium according to one or more of claims 8 to 13.

16. A window comprising the means according to claim 15.

17. A method for preparing the compound of formula I according to claim 1, wherein the method comprises: - Provides I-Br compounds Among them, D, A, Z 2 A 2 Q 2 R 2 And o has the meaning as described in claim 1, and - subject the I-Br compound to a chemical reaction, preferably a cross-coupling reaction.

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