Liquid-crystalline medium

Abstract

The present invention relates to a liquid-crystalline (LC) medium comprising polymerisable compounds, to a process for its preparation, to its use for optical, optoelectronic and electronic purposes, in particular in LC displays, especially in LC displays of the polymer sustained alignment (PSA) type, and to LC displays, especially PSA displays, comprising the medium.

Description

[0001] This application is a divisional application of application number 201680031434.5, filed on April 29, 2016, entitled "Liquid Crystal Medium". Technical Field

[0002] This invention relates to liquid crystal (LC) media containing polymerizable compounds, methods for their preparation, their use for optical, optoelectronic and electronic purposes, particularly in LC displays, especially in polymer stable alignment (PSA) type LC displays, and LC displays containing such media, particularly PSA displays. Background Technology

[0003] One liquid crystal display mode (which has gained widespread attention and commercial use) is the so-called PS (“polymer stabilized”) or PSA (“polymer stabilized alignment”) mode, for which the term “polymer stabilization” is occasionally also used. In PSA displays, an LC medium comprising an LC mixture (hereinafter also referred to herein as the “body mixture”) and small amounts, typically <1 wt%, for example 0.1-0.4 wt%, of one or more polymerizable compounds, preferably polymerizable monomeric compounds, is used. After the LC medium is filled into the display, the polymerizable compound is typically polymerized by UV light, optionally simultaneously polymerized in situ or crosslinked by applying a voltage to the electrodes of the display. Polymerization is carried out at the temperature at which the LC medium exhibits a liquid crystal phase, typically at room temperature. The addition of polymerizable mesocrystalline or liquid crystal compounds, also referred to as reactive mesocrystalline or “RM”, to the LC body mixture has proven particularly suitable.

[0004] PS(A) mode is used in a variety of conventional LC display types. Therefore, for example, PS-VA (Vertical Alignment), PS-OCB ("Optically Compensated Bending"), PS-IPS ("In-Plane Switching"), PS-FFS ("Edge Field Switching"), PS-UB-FFS ("Ultra-High Brightness FFS"), and PS-TN ("Twisted Nematic") displays are known. In the case of PS-VA and PS-OCB displays, RM aggregation is preferably performed using an applied voltage, and in the case of PS-IPS displays, it may or may not be performed, preferably not using an applied voltage. Thus, a pretilt angle of the LC molecules is generated in the display cell. In the case of PS-OCB displays, for example, the bending structure can be stabilized so that the offset voltage is unnecessary or can be reduced. In the case of PS-VA displays, pretilt has a positive effect on response time. For PS-VA displays, standard MVA ("Multi-Domain VA") or PVA ("Patterned VA") pixel and electrode arrangements can be used. It is also possible to use only a single structured electrode without protrusions, which significantly simplifies production and improves contrast and transparency.

[0005] Furthermore, the so-called positive-VA mode (“positive VA”) has proven particularly suitable. Similar to conventional VA and PS-VA displays, the initial orientation of LC molecules in a positive-VA display is vertical, meaning they are substantially perpendicular to the substrate in their initial state without applied voltage. However, unlike conventional VA and PS-VA displays, positive-VA displays utilize an LC dielectric with positive dielectric anisotropy. As with IPS and PS-IPS displays, the two electrodes in a positive-VA display are arranged on only one of the two substrates, and preferably exhibit an interlocking, comb-like (interdigitated) structure. When a voltage is applied to the interdigitated electrodes (which generate an electric field substantially parallel to the LC dielectric layer), the LC molecules switch to an orientation substantially parallel to the substrate. In positive-VA displays, it has also proven advantageous to stabilize the polymer by adding RM, which is subsequently polymerized in the display, to the LC. This allows for a significant reduction in switching time.

[0006] PS-VA displays are described, for example, in EP1170626 A2, US6861107, US7169449, US2004 / 0191428A1, US2006 / 0066793A1, and US2006 / 0103804A1. PS-OCB displays are described, for example, in T.-J-Chen et al., Jpn.J.Appl.Phys.45, 2006, 2702-2704 and S.Kim, L.-C-Chien, Jpn.J.Appl.Phys.43, 2004, 7643-7647. PS-IPS displays are described, for example, in US 6177972 and Appl.Phys.Lett.1999, 75(21), 3264. For example, a PS-TN display is described in Optics Express 2004, 12(7), 1221.

[0007] PSA displays can operate as either active matrix or passive matrix displays. In the case of an active matrix display, individual pixels are typically addressed by integrated nonlinear active elements such as transistors (e.g., thin-film transistors or "TFTs"), while in a passive matrix display, individual pixels are typically addressed by multiplexing methods known in the art.

[0008] PSA displays may also include alignment layers on one or both of the substrates forming the display housing. The alignment layer is typically applied to electrodes (where such electrodes are present) to contact the LC medium and induce the initial alignment of LC molecules. The alignment layer may contain or consist of, for example, polyimide, and may also be rubbed or prepared by photoalignment methods.

[0009] Especially for monitors and particularly TV applications, optimization of response time, as well as the contrast and brightness (and therefore transmittance) of LC displays, remains desirable. The PSA method offers significant advantages here. Particularly in the case of PS-VA, PS-IPS, PS-FFS, and PS-positive-VA displays, the reduction in response time, which is measurable in the test chamber, can be achieved without significantly adversely affecting other parameters.

[0010] The prior art suggests using optional fluorinated biphenyl diacrylate or biphenyl dimethacrylate as the RM in PSA displays.

[0011] However, the problem arises because not all combinations of LC host mixtures and RMs are suitable for PSA displays, as, for example, they may result in insufficient tilt angle or no tilt angle at all, or the voltage retention rate (VHR) may be insufficient for TFT display applications. Furthermore, it has been found that existing LC mixtures and RMs still have some drawbacks when used in PSA displays. Therefore, not every known RM soluble in LC host mixtures is suitable for PSA displays. Moreover, it is often difficult to find suitable selection criteria for RMs other than directly measuring the pretilt in the PSA display. If UV photopolymerization without the addition of a photoinitiator is desired (which is advantageous for some applications), the selection of a suitable RM becomes even more limited.

[0012] Furthermore, the selected combination of LC bulk mixture / RM should have low rotational viscosity and good electrical properties, especially high VHR. In PSA displays, high VHR after UV irradiation is particularly important because UV exposure not only occurs as normal exposure during the final display operation but is also a necessary part of the display manufacturing process.

[0013] In particular, there is a desire for improved materials available for producing particularly small pretilt angles in PSA displays. Preferred materials are those that, compared to prior art materials, produce lower pretilt angles after the same exposure time and / or produce at least the same pretilt angle after a shorter exposure time. This allows for reductions in display production time (“cycle time”) and production costs.

[0014] Another issue in PSA display production is the presence and removal of unreacted refining polymer (RM) remaining after the necessary polymerization step to create the pretilt angle in the display. Unreacted RM can adversely affect display performance, for example, by polymerizing in an uncontrolled manner during display operation.

[0015] Therefore, PSA displays known in the prior art often exhibit an undesirable effect called "image sticking" or "image burn-in," in which an image generated by the brief addressing of a single pixel in a liquid crystal display remains visible even after the electric field in those pixels has been turned off or after other pixels have been addressed.

[0016] For example, image lag can occur if an LC bulk mixture with a low VHR is used. The UV component of sunlight or display backlight can cause undesirable decomposition reactions of the LC molecules and initiate the generation of ionic or free radical impurities. These impurities can accumulate, particularly on the electrodes or alignment layers, where they reduce the effective applied voltage. This effect can also be observed in conventional LC displays without polymer components.

[0017] The additional image sluggishness effect caused by the presence of unpolymerized resonant membranes (RMs) is frequently observed in PSA displays. Uncontrolled polymerization of the remaining RMs is triggered by UV light from the ambient or backlight. In switched display areas, this changes the tilt angle after multiple addressing cycles. Consequently, a transmittance change occurs in the switched area, while it remains unchanged in the unswitched area.

[0018] During PSA display production, it is desirable for RM polymerization to proceed as completely as possible and for the presence of unpolymerized RM in the display to be eliminated or minimized. Therefore, a bulk mixture of RM and LC capable of or supporting rapid and complete RM polymerization is needed. Furthermore, controlled reaction of residual RM is also desirable. This can be achieved by providing an improved RM that polymerizes faster and more efficiently than existing RM technologies.

[0019] Another problem observed in the operation of PSA displays is the stability of the pretilt angle. Therefore, it has been observed that the pretilt angle generated by the polymerization RM during display manufacturing does not remain constant, but deteriorates during display operation after the display has been subjected to voltage stress. This negatively impacts display performance, for example, by increasing black-state transmittance, and thus reducing contrast.

[0020] Another problem to be addressed is that existing RMs often have high melting points and exhibit only limited solubility in many commonly used LC mixtures. Therefore, RMs tend to crystallize spontaneously from LC mixtures. Furthermore, the risk of spontaneous polymerization prevents the LC bulk mixture from being heated to better dissolve RMs, requiring high solubility even at room temperature. Additionally, there is a risk of phase separation, which can significantly impair the homogeneity of the LC display, for example, when the LC medium is filled into the LC display (chromatographic effect). This is further exacerbated by the fact that LC media are typically filled into the display at low temperatures to reduce the risk of spontaneous polymerization (see above), which in turn adversely affects solubility.

[0021] Another problem observed in the prior art is that the use of conventional LC media in LC displays (including but not limited to PSA-type displays) often leads to the appearance of inhomogeneities (mura) in the display, especially when the display is filled using a one-drop filling (ODF) method. This phenomenon is also known as "ODF inhomogeneity." Therefore, it is desirable to provide LC media that reduces ODF inhomogeneity.

[0022] Another problem observed in the prior art is that LC media used in PSA displays (including but not limited to PSA-type displays) often exhibit high viscosity, and therefore high switching times. To reduce the viscosity and response time of LC media, the prior art suggests adding LC compounds with alkenyl groups. However, LC media containing alkenyl compounds have been observed to frequently exhibit reduced reliability and stability, particularly a decrease in VHR after exposure to UV radiation. This is a significant disadvantage, especially for PSA displays, as photopolymerization of RM in PSA displays typically occurs through exposure to UV radiation (which leads to a decrease in VHR in the LC media).

[0023] In the prior art, LC media for PSA displays have been proposed, wherein the LC bulk mixture contains one or more terphenyl compounds to enhance the polymerization of RM. However, the addition of terphenyl compounds increases the viscosity of the LC bulk mixture, thus resulting in a slower response time. Furthermore, the addition of terphenyl compounds can lead to reduced reliability and a decrease in VHR after UV stress in the LC media.

[0024] Therefore, another issue is to provide LC mixtures and LC media for PSA displays that exhibit reduced viscosity and high VHR, while simultaneously enabling RM to polymerize quickly and completely.

[0025] Recently, the use of PSA displays has also been recommended for outdoor applications, such as PIDs (Public Information Displays). PIDs are one of the emerging paradigms in the display market. There is an increasing number of PIDs displaying a wide variety of information in public areas such as train stations, streets, airports, hotels, and shopping malls.

[0026] PID displays are unique compared to conventional LC displays used in applications such as TVs or IT because they are typically installed outdoors. Therefore, PID displays require greater durability to operate consistently under a wide range of environmental conditions and a wider operating temperature range compared to conventional LC displays. Consequently, the LC medium used in PID displays should have a wide LC phase transition and preferably a very high Tni value (the phase transition temperature from nematic to isotropic state, also known as the "clearing temperature" or "clearing point") >100°C.

[0027] However, the LC media proposed for use in PSA displays to date do indeed typically have a Tni value of <100°C.

[0028] Therefore, there remains a significant demand for PSA displays and LC media and polymerizable compounds for PSA displays (especially for outdoor applications) that do not exhibit the aforementioned disadvantages, or exhibit them only to a lesser extent, and have improved properties.

[0029] In particular, there is a significant demand for PSA displays and the LC mixtures and RMs used in such displays, which possess high specific resistivity, a wide operating temperature range, short response time even at low temperatures, low threshold voltage, low pretilt angle, a wide grayscale range, high contrast, and wide viewing angle; high reliability and high VHR value after UV exposure; and, in the case of RMs, low melting point and high solubility in the LC bulk mixture. In PSA displays for mobile applications, available LC media exhibiting low threshold voltage and high birefringence are particularly desirable.

[0030] In PSA displays used in outdoor applications, such as in PID, it is particularly desirable to have an available LC medium with a high Tni, preferably >100°C.

[0031] The present invention is based on the aim of providing novel and suitable materials, particularly for RM, LC body mixtures and LC media containing the same for PSA displays, which do not have or only have a reduced degree of the disadvantages pointed out above.

[0032] Specifically, the present invention is based on the purpose of providing an LC medium for a PSA display that can have very high resistivity, high VHR value, high reliability, low threshold voltage, short response time, high birefringence, and particularly good UV absorption at longer wavelengths, allowing the contained RM to polymerize rapidly and completely, allowing the generation of low pretilt angles as quickly as possible, and high pretilt stability even after long times and / or after UV exposure, reducing or preventing image sticking in the display, and reducing or preventing ODF inhomogeneity in the display.

[0033] Another object of the present invention is to solve the problem of providing LC mixtures and LC media for PSA displays that exhibit reduced viscosity and high VHR while being able to rapidly and completely polymerize RM.

[0034] Another object of the present invention is to solve the problem of providing LC mixtures and LC media (which display high Tni) for PSA displays (such as PID) for outdoor applications.

[0035] The above objectives have been achieved by means of the materials and methods described and claimed in this application, according to the present invention.

[0036] It has been surprisingly discovered that at least some of the problems mentioned above can be solved by using an LC medium comprising a mixture of the polymerizable components disclosed and claimed below and the LC host. It has been found that when such an LC medium is used in a PSA display, high Tni can be obtained while maintaining the low viscosity, high VHR, high UV absorption, and strong tilt angle generation required for rapid and complete polymerization.

[0037] The use of the LC medium according to the invention also facilitates rapid and complete UV photopolymerization reactions, particularly at low UV energy and / or longer UV wavelengths (in the 300-380 nm range, and especially above 340 nm), which is a considerable advantage for display manufacturing processes. Furthermore, the use of the LC medium according to the invention allows for the rapid generation of large and stable pretilt angles, reduces image lag and ODF inhomogeneity in the display, results in high VHR after UV photopolymerization, and enables fast response times, low threshold voltage, and high birefringence.

[0038] The LC medium of the present invention particularly displays high Tni and is therefore especially suitable for PSA displays used in outdoor applications (such as PID). Summary of the Invention

[0039] This invention relates to liquid crystal (LC) media, which comprises

[0040] - Polymerizable component A), comprising one or more polymerizable compounds, preferably composed of the one or more polymerizable compounds, and

[0041] - Liquid crystal component B), also referred to below as "LC host mixture", comprises one or more mesocrystalline or liquid crystal compounds, preferably composed of such compounds, which comprise one or more compounds selected from formulas C, P, T and D.

[0042]

[0043] Each group, when appearing in the same or different manner and independently of the others, has the following meaning:

[0044] for

[0045] for

[0046] for

[0047] e is 1 or 2, preferably 1.

[0048] R 1 and R 2 It is an alkyl group having 1 to 12 carbon atoms, wherein 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 an alkyl or alkoxy group having 1 to 6 carbon atoms.

[0049] R 5 and R 6 It is an alkyl group having 1 to 12 carbon atoms, wherein 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 an alkyl or alkoxy group having 1 to 6 carbon atoms.

[0050] Z x and Z y The bond type can be -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.

[0051] L 1-4 It can be F or Cl, with F being preferred.

[0052] L T1-L T6 The solvent is H, F, or Cl, preferably H or F, wherein L T1 To L T6 At least one of them is F or Cl, preferably F.

[0053] Its characteristic is that it meets the following conditions:

[0054] Component B) contains ≥60% compounds selected from formulas C, P, T, and D.

[0055] Component B) contains ≥50% compounds selected from formulas C, P, and T.

[0056] Component B) contains ≥40% compounds selected from formulas C and P, wherein R 2 It is an alkoxy group having 1 to 12 carbon atoms.

[0057] Component B) contains 1% to 20% of compound D in which e is 1.

[0058] The liquid crystal component B of the LC medium according to the invention is also referred to below as the "LC host mixture", and preferably contains only LC compounds selected from non-polymerizable low molecular weight compounds (such as those of formula C, P, T and D), and optionally contains additives such as polymerization initiators, inhibitors, stabilizers, etc.

[0059] The present invention further relates to LC media or LC displays as described in the context, wherein the polymerizable compound of component A) is polymerized.

[0060] The present invention also relates to a method for preparing LC media as described in the context, comprising the steps of mixing one or more compounds of formula C, P, T and / or D, or LC host mixtures or LC components B as described in the context, with one or more compounds of formula S and with one or more polymerizable compounds and optionally with other LC compounds and / or additives.

[0061] The present invention further relates to the use of LC media in LC displays, particularly PSA displays.

[0062] The present invention also relates to the use of the LC medium of the present invention in a PSA display, particularly in a PSA display containing an LC medium, for generating a tilt angle in the LC medium, which is achieved by causing the polymerizable compound of component B) in the PSA display to polymerize in situ, preferably in an electric or magnetic field.

[0063] The present invention also relates to LC displays comprising one or more compounds of Formula I or the LC media of the present invention, particularly PSA displays, especially PS-VA, PS-IPS or PS-UB-FFS displays or related modes using LC materials with Δε<0.

[0064] The present invention also relates to polymers that can be obtained by polymerization of one or more compounds of formula I as described above or polymerizable component A), or LC displays that contain LC media according to the present invention, preferably PSA displays, very preferably PS-VA, PS-IPS or PS-UB-FFS displays, or related modes using LC materials with Δε<0.

[0065] The present invention also relates to a PSA-type LC display comprising two substrates (at least one of which is light-transparent), one electrode provided on each substrate or two electrodes provided on only one substrate, and a layer of LC medium located between the substrates, the LC medium comprising one or more polymerizable compounds and LC components as described in the context, wherein the polymerizable compounds are polymerized between the substrates of the display.

[0066] The present invention also relates to a method of manufacturing an LC display as described in the context, comprising filling or otherwise providing an LC medium comprising one or more polymerizable compounds as described in the context between substrates of the display, and the step of polymerizing the polymerizable compounds.

[0067] The PSA display according to the invention has two electrodes, preferably in the form of a transparent layer, applied to one or both substrates. In some displays, such as PS-VA displays, the electrodes are applied to each of the two substrates. In other displays, such as PS-IPS or PS-UB-FFS displays, or in related modes using LC materials with Δε<0, the two electrodes are applied to only one of the two substrates.

[0068] In a preferred embodiment, polymerizable components are polymerized in the LC display when a voltage is applied to the electrodes of the display.

[0069] The polymerizable compound of the polymerizable component is preferably polymerized by photopolymerization, and very preferably by UV-photopolymerization. Detailed Implementation

[0070] Unless otherwise stated, polymerizable compounds are preferably selected from achiral compounds.

[0071] As used herein, the terms “active layer” and “switchable layer” refer to a layer in an optoelectronic display, such as an LC display, comprising one or more molecules (e.g., LC molecules) having structural and optical anisotropy, which change their orientation when subjected to external stimuli such as an electric or magnetic field, resulting in a change in the layer’s transmittance to polarized or unpolarized light.

[0072] As used herein, the terms "tilt" and "tilt angle" will be understood to refer to the tilted orientation of LC molecules of the LC medium relative to the cell surface in an LC display (preferably a PSA display). The tilt angle here represents the average angle (<90°) between the longitudinal molecular axis (LC director) of the LC molecules and the outer plate parallel to the plane forming the LC cell. Lower tilt angle values ​​(i.e., larger deviations from 90°) correspond to larger tilts. Suitable methods for measuring the tilt angle are provided in the embodiments. Unless otherwise stated, the tilt angle values ​​disclosed in the context are related to this measurement method.

[0073] As used herein, the terms “reactive mesocrystalline” and “RM” will be understood to mean a compound comprising a mesocrystalline or liquid crystal framework and one or more functional groups attached thereto suitable for polymerization, and said functional groups are also referred to as “polymerizable groups” or “P”.

[0074] Unless otherwise stated, the term “polymerizable compound” as used herein shall be understood as a polymerizable monomeric compound.

[0075] As used herein, the term “low molecular weight compound” will be understood to mean a monomeric compound and / or a compound not prepared by polymerization, as opposed to “polymeric compound” or “polymer”.

[0076] As used herein, the term "non-polymerizable compound" will be understood to mean a compound that does not contain functional groups suitable for polymerization under the conditions typically applied to RM polymerization.

[0077] As used herein, the term "mesocrystalline group" is known to those skilled in the art and described in the literature, and it refers to a group that substantially contributes to the formation of a liquid crystal (LC) phase in a low molecular weight or polymeric substance due to the anisotropy of its attractive and repulsive interactions. A compound containing a mesocrystalline group (mesocrystalline compound) does not necessarily have an LC phase by itself. Mesocrystalline compounds can exhibit LC phase behavior only when mixed with other compounds and / or after polymerization. Typical mesocrystalline groups are, for example, rigid rod-shaped or disk-shaped units. Terms and definitions used in connection with mesocrystalline or LC compounds are given in Pure Appl. Chem. 2001, 73(5), 888 and C. Tschierske, G. Pelzl, S. Diele, Angew. Chem. 2004, 116, 6340-6368.

[0078] As used herein, the term "spacer group" (hereinafter also referred to as "Sp") is known to those skilled in the art and described in the literature, see, for example, Pure Appl. Chem. 2001, 73(5), 888 and C. Tschierske, G. Pelzl, S. Diele, Angew. Chem. 2004, 116, 6340-6368. As used herein, the term "spacer group" or "spacer base" means a flexible group, such as an alkylene group, that connects a mesocrystalline group to a polymerizable group in a polymerizable mesocrystalline compound.

[0079] In the context,

[0080]

[0081] Represents the trans-1,4-cyclohexyl ring, and

[0082]

[0083] It represents a 1,4-phenylene ring.

[0084] In this context, "organic group" refers to a carbon-based or hydrocarbon-based group.

[0085] "Carbon group" refers to a monovalent or polyvalent organic group containing at least one carbon atom, wherein the group does not contain other atoms (e.g., -C≡C-) or optionally contains one or more other atoms, such as N, O, S, B, P, Si, Se, As, Te, or Ge (e.g., carbonyl group). The term "hydrocarbon group" refers to a carbon group that additionally contains one or more H atoms and optionally one or more heteroatoms, such as N, O, S, B, P, Si, Se, As, Te, or Ge.

[0086] "Halogen" refers to F, Cl, Br, or I.

[0087] “O · "" indicates oxygen free radicals.

[0088] -CO-, -C(=O)-, and -C(O)- represent carbonyl groups, i.e.

[0089] The carbonyl or hydrocarbon group can be saturated or unsaturated. Unsaturated groups are, for example, aryl, alkenyl, or alkynyl groups. The carbonyl or hydrocarbon group having more than 3 carbon atoms can be straight-chain, branched, and / or cyclic, and may also contain helical links or fused rings.

[0090] The terms "alkyl", "aryl", and "heteroaryl" also include polyvalent groups, such as alkylene, arylene, and heteroarylene.

[0091] The term "aryl" refers to an aromatic carbon group or a group derived therefrom. The term "heteroaryl" refers to an "aryl" as defined above that contains one or more heteroatoms (preferably selected from N, O, S, Se, Te, Si, and Ge).

[0092] Preferred carbonyl and hydrocarbon groups are optionally substituted, and are straight-chain, branched, or cyclic alkyl, alkenyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyl, and alkoxycarbonyloxy groups having 1 to 40, preferably 1 to 20, very preferably 1 to 12 carbon atoms; optionally substituted aryl or aryloxy groups having 5 to 30, preferably 6 to 25 carbon atoms; or optionally substituted alkylaryl, aralkyl, alkylaryloxy, arylalkyloxy, arylcarbonyl, aryloxycarbonyl, arylcarbonyloxy, and aryloxycarbonyloxy groups having 5 to 30, preferably 6 to 25 carbon atoms, wherein one or more carbon atoms may also be replaced by heteroatoms (preferably selected from N, O, S, Se, Te, Si, and Ge).

[0093] Further preferred carbon-based and hydrocarbon-based groups are C1-C. 20 Alkyl, C2-C 20 alkenyl, C2-C 20 alkynyl group, C3-C 20 Allyl, C4-C 20 Alkyl diene group, C4-C 20 Polyene, C6-C 20 cycloalkyl, C4-C 15 Cycloalkenyl, C6-C 30 Aryl, C6-C 30 Alkyl aryl, C6-C 30 Aryl group, C6-C 30 Alkyl aryloxy, C6-C 30 arylalkoxy, C2-C 30 heteroaryl, C2-C 30 heteroaryloxyl.

[0094] C1-C is particularly preferred. 12 Alkyl, C2-C 12 Alkenyl, C2-C 12 alkynyl group, C6-C 25 Aryl and C2-C 25 Mixed aromatic compounds.

[0095] Further preferred carbonyl and hydrocarbon groups are straight-chain, branched, or cyclic alkyl groups having 1 to 20, preferably 1 to 12, carbon atoms, which are unsubstituted or mono- or polysubstituted with F, Cl, Br, I, or CN, and wherein one or more non-adjacent CH2 groups may be independently converted to -C(R) x )=C(R x )-、-C≡C-、-N(Rx -, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-, -O-CO-O- are replaced by O and / or S atoms that are not directly connected to each other.

[0096] R x Preferably, it represents H, F, Cl, CN, a straight-chain, branched, or cyclic alkyl chain having 1 to 25 C atoms, wherein one or more non-adjacent C atoms may be replaced by -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O-, and one or more H atoms may be replaced by F or Cl, or it represents an optionally substituted aryl or aryloxy group having 6 to 30 C atoms, or an optionally substituted heteroaryl or heteroaryloxy group having 2 to 30 C atoms.

[0097] Preferred alkyl groups include, 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, dodecyl, trifluoromethyl, perfluoron-butyl, 2,2,2-trifluoroethyl, perfluorooctyl, perfluorohexyl, etc.

[0098] Preferred alkenyl groups include, for example, vinyl, propenyl, butenyl, pentenyl, cyclopentenyl, hexenyl, cyclohexenyl, heptenyl, cycloheptenyl, octenyl, cyclooctenyl, etc.

[0099] Preferred alkynyl groups include, for example, ethynyl, propynyl, butynyl, penynyl, hexynyl, octyynyl, etc.

[0100] Preferred alkoxy groups include, 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, n-dodecoxy, etc.

[0101] Preferred amino groups include, for example, dimethylamino, methylamino, methylphenylamino, phenylamino, etc.

[0102] Aryl and heteroaryl groups can be monocyclic or polycyclic, meaning they can contain one ring (e.g., phenyl) or two or more rings, and can be fused (e.g., naphthyl) or covalently bonded (e.g., biphenyl), or a combination of fused and linking rings. Heteroaryl groups contain one or more heteroatoms, preferably selected from O, N, S, and Se.

[0103] Particularly preferred are mono-, di-, or tricyclic aryl groups having 6-25 carbon atoms and mono-, di-, or tricyclic heteroaryl groups having 5-25 ring atoms, optionally containing a fused ring and optionally substituted. Further preferred are 5-, 6-, or 7-membered aryl and heteroaryl groups, wherein 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 linked to each other.

[0104] Preferred aryl groups include, for example, phenyl, biphenyl, terphenyl, [1,1':3',1”]-terphenyl-2'-yl, naphthyl, anthraceneyl, binatyl, phenanthryl, 9,10-dihydro-phenanthryl, pyrene, dihydropyrene, Dinaphthylbenzene, tetraphenylbenzene, pentaphenylbenzene, benzo[a]pyrene, fluorene, indene, indo[a]fluorene, spirobifluorene, etc.

[0105] 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, 6-membered rings, such as pyridine, pyridazine, pyrimidine, pyrazine, 1,3,5-triazine, 1,2,4-triazine, 1,2,3-triazine, 1,2,4,5-tetraazine, 1,2,3,4-tetraazine, 1,2,3,5-tetraazine, or fused groups, such as indole, isoindole. Indazine, Indazole, Benzimidazole, Benzitriazole, Purine, Naphthemidazole, Phenylenazole, Pyridinazole, Pyrazinazole, Quinoxaline, Benzooxazole, Naphthemidazole, Anthrazooxazole, Phenylenazole, Isoxazole, Benzothiazol, Benzofuran, Isobenzofuran, Dibenzofuran, Quinoline, Isoquinoline, Pteridine, Benzo-5,6-quinoline, Benzo-6,7-quinoline Benzo-7,8-quinoline, benzoisoquinoline, acridine, phenothiazine, phenothiazine, benzopyridinium, quinoxaline, phenothiazine, naphthidine, azacarbazole, benzocarbine, phenanthridine, phenanthroxaline, thieno[2,3b]thiophene, thieno[3,2b]thiophene, dithieno[2,3b]thiophene, isobenzothiophene, dibenzothiophene, benzothiadiazolethiophene, or combinations of these groups.

[0106] The aryl and heteroaryl groups mentioned in the context may also be substituted by alkyl, alkoxy, thioalkyl, fluorine, fluoroalkyl or other aryl or heteroaryl groups.

[0107] (Non-aromatic) alicyclic and heterocyclic groups can include both saturated rings (i.e., rings containing only single bonds) and partially unsaturated rings (i.e., those containing multiple bonds). Heterocyclic groups contain one or more heteroatoms, preferably selected from Si, O, N, S, and Se.

[0108] The (non-aromatic) alicyclic and heterocyclic groups can be monocyclic, i.e., containing only one ring (e.g., cyclohexane), or polycyclic, i.e., containing multiple rings (e.g., decahydronaphthalene or bicyclooctane). Saturated groups are particularly preferred. Furthermore, mono-, bi-, or tricyclic groups having 5-25 ring atoms are preferred, optionally containing fused rings and optionally substituted. Further preferred are 5-, 6-, 7-, or 8-membered carbocyclic groups, wherein one or more C 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-.

[0109] Preferred alicyclic and heterocyclic groups are, for example, 5-membered groups, such as cyclopentane, tetrahydrofuran, tetrahydrothiophene, and pyrrolidine; 6-membered groups, such as cyclohexane, silinane, cyclohexene, tetrahydropyran, tetrahydrothioran, 1,3-dioxane, 1,3-dithiane, and 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, and octahydro-4,7-bridged methylene indane-2,5-diyl.

[0110] Preferred substituents are, for example, solubility-promoting groups, such as alkyl or alkoxy groups; electron-withdrawing groups, such as fluorine, nitro or nitrile groups; or substituents used to increase the glass transition temperature (Tg) of the polymer, especially bulky groups, such as tert-butyl or optionally substituted aryl groups.

[0111] Preferred substituents, also referred to as "L" below, are F, Cl, Br, I, -CN, -NO2, -NCO, -NCS, -OCN, -SCN, and -C(=O)N(R). x )2、-C(=O)Y 1 -C(=O)R x -N(R) x 2, each having 1 to 25 carbon atoms, a straight-chain or branched alkyl, alkoxy, alkyl carbonyl, alkoxy carbonyl, alkyl carbonyloxy, or alkoxy carbonyloxy group, wherein one or more H atoms are optionally replaced by F or Cl, optionally substituted silyl groups having 1 to 20 Si atoms, or optionally substituted aryl groups having 6 to 25, preferably 6 to 15, carbon atoms.

[0112] Where R xRepresents H, F, Cl, CN, or a straight-chain, branched, or cyclic alkyl group having 1 to 25 C atoms, wherein one or more non-adjacent CH2- groups are optionally replaced by -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O- in such a way that the O- and / or S- atoms are not directly connected to each other, and wherein one or more H atoms are each optionally replaced by F, Cl, P-, or P-Sp-, and

[0113] Y 1 It represents halogens.

[0114] "Substituted silyl or aryl" preferably indicates that it is substituted with halogen, -CN, R 0 -OR 0 -CO-R 0 -CO-OR 0 -O-CO-R 0 OR-O-CO-OR 0 Replace, where R 0 It represents H or an alkyl group having 1 to 20 carbon atoms.

[0115] Particularly preferred substituents L include, for example, F, Cl, CN, NO2, CH3, C2H5, OCH3, OC2H5, COCH3, COC2H5, COOCH3, COOC2H5, CF3, OCF3, OCHF2, OC2F5, and also phenyl.

[0116] Preferred

[0117] L has one of the meanings mentioned above.

[0118] The polymerizable group P is a group suitable for polymerization reactions (e.g., free radical or ionic chain polymerization, addition polymerization, or condensation polymerization), or a group suitable for polymer-analogous reactions (e.g., addition or condensation on the polymer backbone). Groups suitable for chain polymerization are particularly preferred, especially those containing C=C double bonds or -C≡C- triple bonds, and groups suitable for ring-opening polymerization, such as oxetyl or epoxy groups.

[0119] The preferred group P is selected from the following groups: CH2=CW 1 -CO-O-、CH2=CW 1 -CO-、 CH2=CW 2 -(O) k3 -、CW 1 =CH-CO-(O) k3 -、CW 1=CH-CO-NH-, CH2=CW 1 -CO-NH-, CH3-CH=CH-O-, (CH2=CH)2CH-OCO-, (CH2=CH-CH2)2CH-OCO-, (CH2=CH)2CH-O-, (CH2=CH-CH2)2N-, (CH2=CH-CH2)2N-CO-, HO-CW 2 W 3 -、HS-CW 2 W 3 -、HW 2 N-, HO-CW 2 W 3 -NH-, CH2=CW 1 -CO-NH-, CH2=CH-(COO) k1 -Phe-(O) k2 - CH2=CH-(CO) k1 -Phe-(O) k2 -, Phe-CH=CH-, HOOC-, OCN- and W 4 W 5 W 6 Si-, where W 1 It represents H, F, Cl, CN, CF3, phenyl, or alkyl groups having 1 to 5 carbon atoms, especially H, F, Cl, or CH3, W 2 and W 3 Each independently represents H or an alkyl group having 1 to 5 carbon atoms, particularly H, methyl, ethyl, or n-propyl, W 4 W 5 and W 6 Each independently represents Cl, an oxaalkyl or oxacarbonylalkyl group having 1 to 5 carbon atoms, and W. 7 and W 8 Each of the above-defined groups independently represents H, Cl, or an alkyl group having 1 to 5 C atoms; Phe represents 1,4-phenylene, which is optionally substituted with one or more L groups other than P-Sp- as defined above; k1, k2, and k3 each independently represent 0 or 1, k3 preferably represents 1, and k4 represents an integer from 1 to 10.

[0120] The preferred group P is selected from the following groups: CH2=CW 1 -CO-O-、CH2=CW 1 -CO-、 CH2=CW 2 -O-、CH2=CW 2 -,CW 1 =CH-CO-(O) k3 -、CW1 =CH-CO-NH-, CH2=CW 1 -CO-NH-, (CH2=CH)2CH-OCO-, (CH2=CH-CH2)2CH-OCO-, (CH2=CH)2CH-O-, (CH2=CH-CH2)2N-, (CH2=CH-CH2)2N-CO-, CH2=CW 1 -CO-NH-, CH2=CH-(COO) k1 -Phe-(O) k2 - CH2=CH-(CO) k1 -Phe-(O) k2 - Phe-CH=CH- and W 4 W 5 W 6 Si-, where W 1 It represents H, F, Cl, CN, CF3, phenyl, or alkyl groups having 1 to 5 carbon atoms, especially H, F, Cl, or CH3, W 2 and W 3 Each independently represents H or an alkyl group having 1 to 5 carbon atoms, particularly H, methyl, ethyl, or n-propyl, W 4 W 5 and W 6 Each independently represents Cl, an oxaalkyl or oxacarbonylalkyl group having 1 to 5 carbon atoms, and W. 7 and W 8 Each of them independently represents H, Cl or an alkyl group having 1 to 5 C atoms, Phe represents 1,4-phenylene, k1, k2 and k3 each independently represent 0 or 1, k3 preferably represents 1, and k4 represents an integer from 1 to 10.

[0121] The highly preferred group P is selected from CH2=CW. 1 -CO-O-, especially CH2=CH-CO-O-, CH2=C(CH3)-CO-O- and CH2=CF-CO-O-, in addition to CH2=CH-O-, (CH2=CH)2CH-O-CO-, (CH2=CH)2CH-O-, and (CH2=CH)2CH-O-.

[0122] Further preferred polymerizable groups P are selected from ethylene oxy, acrylate, methacrylate, fluoroacrylate, chloroacrylate, oxetyl, and epoxy groups, with the most preferred groups being acrylate and methacrylate.

[0123] If Sp is different from a single bond, it is preferably of the formula Sp"-X, such that each group P-Sp- is equivalent to the formula P-Sp"-X"-, wherein

[0124] "Sp" represents an alkylene group having 1 to 20, preferably 1 to 12, carbon atoms, optionally mono- or polysubstituted with F, Cl, Br, I, or CN, and wherein one or more non-adjacent CH2 groups are each independently substituted with -O-, -S-, -NH-, or -N(R) 0 )-、-Si(R 0 R 00 )-, -CO-, -CO-O-, -O-CO-, -O-CO-O-, -S-CO-, -CO-S-, -N(R 00 -CO-O-、-O-CO-N(R) 0 )-、-N(R 0 )-CO-N(R 00 -, -CH=CH-, or -C≡C- are substituted by O and / or S atoms not being directly connected to each other.

[0125] X" means -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O-, -CO-N(R 0 )-、-N(R 0 )-CO-、-N(R 0 )-CO-N(R 00 )-, -OCH2-, -CH2O-, -SCH2-, -CH2S-, -CF2O-, -OCF2-, -CF2S-, -SCF2-, -CF2CH2-, -CH2CF2-, -CF2CF2-, -CH=N-, -N=CH-, -N=N-, -CH=CR 0 -、-CY 2 =CY 3 -, -C≡C-, -CH=CH-CO-O-, -O-CO-CH=CH- or single bonds

[0126] R 0 and R 00 Each independently represents H or an alkyl group having 1-20 carbon atoms, and

[0127] Y 2 and Y 3 Each can be represented independently as H, F, Cl, or CN.

[0128] X" is preferably -O-, -S-, -CO-, -COO-, -OCO-, -O-COO-, or -CO-NR. 0 -、-NR 0 -CO-、-NR 0 -CO-NR 00 - or a single key.

[0129] Typical spacer groups are Sp and -Sp"-X"-, for example, -(CH2). p1 -,-(CH2CH2O) q1 -CH2CH2-, -CH2CH2-S-CH2CH2-, -CH2CH2-NH-CH2CH2- or -(SiR) 0 R 00 -O) p1 - where p1 is an integer from 1 to 12, q1 is an integer from 1 to 3, and R 0 and R 00 It has the meanings mentioned above.

[0130] The highly preferred groups Sp and -Sp”-X”- are selected from -(CH2). p2 -、-(CH2) p2 -O-、-(CH2) p2 -CO-O-、-(CH2) p2 -O-CO-, where p2 is 2, 3, 4, 5 or 6, and the O atom or CO group is attached to the benzene ring.

[0131] The particularly preferred group Sp" in each case is a straight-chain ethylene, propylene, butylene, pentylene, hexylene, heptylene, octylene, nonylene, decylene, undecylene, dodecylene, octadecylene, ethyleneoxyethylene, methyleneoxybutylene, ethylenethioethylene, ethylene-N-methylimino-ethylene, 1-methylalkylene, vinylene, propenylene, and butenylene.

[0132] Other preferred polymerizable compounds contain a spacer group Sp connected to at least two polymerizable groups P, such that the group Sp-P corresponds to Sp(P). s Where s ≥ 2 (branched polymerizable groups). Preferred polymerizable compounds of this preferred embodiment are those where s is 2, i.e., compounds containing the group Sp(P)2. Very preferred polymerizable compounds of this preferred embodiment contain groups selected from the following formula:

[0133] -X-alkyl-CHPP S1

[0134] -X-alkyl-CH((CH2) aa P)((CH2) bb P) S2

[0135] -X-NH((CH2) aa P)((CH2) bb P) S3

[0136] -X-alkyl-CHP-CH2-CH2P S4

[0137] -X-alkyl-C(CH2P)(CH2P)-C aa H 2aa+1 S5

[0138] -X-alkyl-CHP-CH2P S6

[0139] -X-alkyl-CPP-C aa H 2aa+1 S7

[0140] -X-alkyl-CHPCHP-C aa H 2aa+1 S8

[0141] Where P is defined as in Equation I.

[0142] Alkyl refers to a straight-chain or branched alkylene group with a single bond or having 1 to 12 carbon atoms, which is unsubstituted or monosubstituted or polysubstituted with F, Cl or CN, and wherein one or more non-adjacent CH2 groups are independently bonded to each other in a manner in which the O and / or S atoms are not directly connected to each other. 0 )=C(R 0 )-、-C≡C-、-N(R 0 )-, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O- substitution, where R 0 It has the meaning indicated above.

[0143] aa and bb each independently represent 0, 1, 2, 3, 4, 5, or 6.

[0144] X has one of the meanings indicated by "X", and is preferably O, O-CO-, CO-O or a single bond.

[0145] The preferred spacer group Sp(P)2 is selected from formulas S1, S2 and S3.

[0146] The highly preferred spacer group Sp(P)2 is selected from the following formulas:

[0147] -CHPP S1a

[0148] -O-CHPP S1b

[0149] -CH2-CHPP S1c

[0150] -OCH2-CHPP S1d

[0151] -CH(CH2-P)(CH2-P) S2a

[0152] -OCH(CH2-P)(CH2-P) S2b

[0153] -CH2-CH(CH2-P)(CH2-P) S2c

[0154] -OCH2-CH(CH2-P)(CH2-P) S2d

[0155] -CO-NH((CH2)2P)((CH2)2P) S3a

[0156] Among compounds of formulas C and P, L is preferred. 1 and L 2 Indicates F or L 1 and L 2 One of them represents F and the other represents Cl, with L being preferred. 3 and L 4 Indicates F or L 3 and L 4 One of them represents F and the other represents Cl.

[0157] Among compounds of formulas C, P, T, and D, R is preferred. 1 R 2 R 5 and R 6 It is selected from alkyl and alkoxy groups having 1 to 12 C atoms, preferably 1 to 6 C atoms, and the group is preferably straight-chain or branched.

[0158] In another preferred embodiment of the invention, the LC medium does not contain compounds of the formula C, P, T or D containing an alkenyl group.

[0159] Preferred component B) contains 60% to 80%, very preferably 60% to 70% of compounds selected from formulas C, P, T and D and their derivatives.

[0160] Preferred component B) contains 50% to 80%, very preferably 50% to 65%, of a compound selected from formulas C, P and T and their derivatives.

[0161] Preferred component B) contains 20% to 80%, very preferably 30% to 70% of compounds of formula C and P and their derivatives.

[0162] Preferred component B) contains 10% to 70%, very preferably 15% to 60% of compounds of formulas C and P and their derivatives, wherein R 2 It is an alkoxy group.

[0163] Preferred component B) contains 5% to 30% compounds of formulas C and P and their derivatives, wherein R 2 It is an alkyl group.

[0164] Preferred component B) contains 1% to 15% of compound D.

[0165] Compounds of formula C are preferably selected from the following sub-formulas:

[0166]

[0167]

[0168]

[0169] Where a represents 2, alkyl, and alkyl * Each of these terms independently represents 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, with (O) representing 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-.

[0170] Compounds selected from formulas C1, C2, C9, and C10 are highly preferred. Compounds selected from formulas C1 and C2 are most preferred.

[0171] Preferred component B) contains 5% to 70%, very preferably 10% to 60% of compound of formula C, wherein R 2 It is an alkoxy group having 1 to 12 C atoms, preferably selected from formula C2.

[0172] Preferred component B) contains 1% to 20%, very preferably 2% to 10%, of compound C, wherein R 2 It is an alkyl group having 1 to 12 carbon atoms, preferably selected from formula C1.

[0173] Preferably, the LC medium contains 1 to 8, most preferably 1 to 5, compounds of the formula C or C1-C15.

[0174] Compounds of formula P are preferably selected from the following sub-formulas:

[0175]

[0176]

[0177]

[0178] Among them alkyl and alkyl *Each of these terms independently represents 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, with (O) representing 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-.

[0179] Compounds selected from formulas P1, P2, P13, and P14 are highly preferred. Compounds selected from formulas P1 and P2 are most preferred.

[0180] Preferably, component B) contains 5% to 50%, most preferably 5% to 40%, of compound P, wherein R 2 It is an alkoxy group having 1 to 12 C atoms, preferably selected from formula P2.

[0181] Preferably, the LC medium contains 1 to 8, most preferably 1 to 5, compounds of the formula P or P1-P16.

[0182] Compounds of formula T are preferably selected from the following sub-formulas:

[0183]

[0184]

[0185] Where R represents a straight-chain alkyl or alkoxy group having 1 to 7 carbon atoms, R * R represents a straight-chain alkenyl group with 2 to 7 carbon atoms, (O) represents an oxygen atom or a single bond, and m represents an integer from 1 to 6. * The preferred representations are 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-.

[0186] R and R * Preferably, it represents methyl, ethyl, propyl, butyl, pentyl, hexyl, methoxy, ethoxy, propoxy, butoxy, or pentoxy.

[0187] Compounds of formulas T1, T2, and T3 are highly preferred, especially those having formulas T1 and T2. Compounds of formula T1 are most preferred.

[0188] Highly preferred are compounds of formulas T1-T24, wherein (O) represents an oxygen atom, m is 1, 2, 3, 4 or 5 and R is methyl, ethyl, propyl, butyl, pentyl or hexyl, preferably linear.

[0189] Further preferred are compounds of formula T1, wherein (O) represents a single bond, m is 1, 2, 3, 4 or 5 and R is methyl, ethyl, propyl, butyl, pentyl or hexyl, preferably linear.

[0190] Preferably, the LC medium does not contain more than 15% of compounds of formula T or T1-T24 or any other compound having a triphenyl group.

[0191] Preferred component B) contains 2 to 15%, very preferably 3% to 10%, of a compound of formula T, preferably selected from formulas T1, T2 and T3.

[0192] Preferably, the LC medium contains 1 to 5, most preferably 1 or 2, compounds of formula T or T1-T24.

[0193] Compound D is preferably selected from the following sub-formulas:

[0194]

[0195]

[0196]

[0197] Among them alkyl and alkyl * Each of these terms independently represents 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-.

[0198] Compounds of formulas D1-D8 are highly preferred, especially those having formulas D1, D2, D4, and D5. Compounds of formulas D1 and D4 are most preferred.

[0199] Preferred component B) contains 1% to 15% of compound of formula D, preferably selected from formulas D1 and D4.

[0200] Preferably, the LC medium contains 1 to 5, most preferably 1 to 3, compounds of formula D or D1-D12.

[0201] In the LC media of the present invention, the use of an LC bulk mixture comprising compounds of formula C and / or P and / or T and / or D, together with the use of a polymerizable component comprising preferably di-reactive and / or tri-reactive RM, produces advantageous properties in a PSA display. In particular, one or more of the following advantages can be achieved:

[0202] -High Tni,

[0203] - It also exhibits good UV absorption at longer wavelengths.

[0204] - Fast and complete RM aggregation

[0205] - Rapid generation of low pretilt angles, especially at low UV energies and / or longer UV wavelengths.

[0206] -High UV absorption,

[0207] -Increased UV stability,

[0208] -High pretilt stability after UV exposure

[0209] - Reduced image viscosity

[0210] - Reduced ODF inhomogeneity

[0211] - High reliability and high VHR value after UV exposure and / or heat treatment

[0212] High birefringence,

[0213] - Reduced viscosity,

[0214] - Faster response time.

[0215] Since the LC medium of the present invention exhibits high absorption at longer UV wavelengths, it can be polymerized using longer UV wavelengths, which is advantageous for display manufacturing methods.

[0216] The polymerizable compound is preferably selected from formula I

[0217] R a -B 1 -(Z b -B 2 ) m -R b I

[0218] Each group, when appearing in the same or different manner and independently of the others, has the following meaning:

[0219] R a and R bThis indicates P, P-Sp-, H, F, Cl, Br, I, -CN, -NO2, -NCO, -NCS, -OCN, -SCN, SF5, or a straight-chain or branched alkyl group having 1-25 C atoms, wherein one or more non-adjacent CH2 groups may be independently separated from each other by -C(R) 0 )=C(R 00 )-、-C≡C-、-N(R 00 -, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-, -O-CO-O- are substituted in such a way that the O and / or S atoms are not directly connected to each other, and wherein one or more H atoms may be substituted by F, Cl, Br, I, CN, P or P-Sp-, wherein if B 1 and / or B 2 If R contains saturated C atoms, then a and / or R b It can also represent a group that is spiro-linked to the saturated C atom.

[0220] Wherein group R a and R b At least one of them represents or contains the group P or P-Sp-,

[0221] P represents a polymerizable group.

[0222] Sp represents a spacer group or a single bond.

[0223] B 1 and B 2 It represents an aromatic, heteroaromatic, alicyclic, or heterocyclic group, preferably having 4-25 ring atoms, and may also contain a fused ring, and is unsubstituted, or mono- or polysubstituted with L.

[0224] Z b Represents -O-, -S-, -CO-, -CO-O-, -OCO-, -O-CO-O-, -OCH2-, -CH2O-, -SCH2-, -CH2S-, -CF2O-, -OCF2-, -CF2S-, -SCF2-, -(CH2) n1 -, -CF2CH2-, -CH2CF2-, -(CF2) n1 -, -CH=CH-, -CF=CF-, -C≡C-, -CH=CH-COO-, -OCO-CH=CH-, CR 0 R 00 Or a single key,

[0225] R 0 and R 00 Each can independently represent H or an alkyl group having 1-12 carbon atoms.

[0226] m represents 0, 1, 2, 3, or 4.

[0227] n1 represents 1, 2, 3, or 4.

[0228] L represents P, P-Sp-, OH, CH2OH, F, Cl, Br, I, -CN, -NO2,--NCO, -NCS, -OCN, -SCN, -C(=O)N(R x )2、-C(=O)Y 1 -C(=O)R x -N(R) x 2. Optionally substituted silyl groups, optionally substituted aryl groups having 6-20 carbon atoms, or straight-chain or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy, or alkoxycarbonyloxy groups having 1-25 carbon atoms, wherein one or more H atoms may be substituted with F, Cl, P, or P-Sp-.

[0229] P and Sp have the meanings indicated above.

[0230] Y 1 Indicates halogen,

[0231] R x The symbol represents P, P-Sp-, H, halogen, a straight-chain, branched, or cyclic alkyl group having 1-25 C atoms, wherein one or more non-adjacent CH2 groups may be replaced by -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O- in such a way that the O and / or S atoms are not directly connected to each other, and wherein one or more H atoms may be replaced by F, Cl, P, or P-Sp-, optionally substituted aryl or aryloxy groups having 6-40 C atoms, or optionally substituted heteroaryl or heteroaryloxy groups having 2-40 C atoms.

[0232] The particularly preferred compounds of formula I are those in the following, wherein B 1 and B 2Each of these groups independently represents 1,4-phenylene, 1,3-phenylene, naphthalene-1,4-diyl, naphthalene-2,6-diyl, phenanthrene-2,7-diyl, 9,10-dihydro-phenanthrene-2,7-diyl, anthracene-2,7-diyl, fluorene-2,7-diyl, coumarin, and flavonoids, wherein one or more CH groups in these groups may be replaced by N, cyclohexane-1,4-diyl, wherein one or more non-adjacent CH2 groups may be replaced by O and / or S, 1 ,4-cyclohexenyl, bicyclo[1.1.1]pentane-1,3-diyl, bicyclo[2.2.2]octane-1,4-diyl, spiro[3.3]heptane-2,6-diyl, piperidine-1,4-diyl, decahydronaphthalene-2,6-diyl, 1,2,3,4-tetrahydronaphthalene-2,6-diyl, indane-2,5-diyl or octahydro-4,7-bridged methylene indane-2,5-diyl, wherein all of these groups may be unsubstituted or mono- or polysubstituted as described above.

[0233] The particularly preferred compound of formula I is wherein B is... 1 and B 2 Those that independently represent 1,4-phenylene, 1,3-phenylene, naphthalene-1,4-diyl, or naphthalene-2,6-diyl.

[0234] The most preferred compounds of formula I are selected from the following formulas:

[0235]

[0236]

[0237]

[0238]

[0239] Each group, when appearing in the same or different manner and independently of the others, has the following meaning:

[0240] P 1 P 2 P 3 This indicates ethyleneoxy, acrylate, methacrylate, fluoroacrylate, chloroacrylate, oxetyl, or epoxy groups.

[0241] Sp 1 Sp 2 Sp 3 Indicates a single bond or a spacer group, wherein, in addition, group P 1 -Sp 1 -、P 1 -Sp 2 -and P 3 -Sp 3One or more of them can represent R. aa The condition is that the group P exists. 1 -Sp 1 -、P 2 -Sp 2 and P 3 -Sp 3 - at least one of them is different from R aa ,

[0242] R aa Represents H, F, Cl, CN, or a straight-chain or branched alkyl group having 1-25 C atoms, wherein one or more non-adjacent CH2 groups may be independently bounded by C(R) 0 )=C(R 00 )-、-C≡C-、-N(R 0 -, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-, -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 replaced by F, Cl, CN or P. 1 -Sp 1 - Alternatives, particularly preferred, are straight-chain or branched, optionally mono- or polyfluorinated alkyl, alkoxy, alkenyl, alkynyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy, or alkoxycarbonyloxy groups having 1-12 carbon atoms (wherein the alkenyl and alkynyl groups have at least two carbon atoms and the branched groups have at least three carbon atoms).

[0243] R 0 R 00 It represents H or an alkyl group having 1-12 carbon atoms.

[0244] R y and R z Indicates H, F, CH3 or CF3,

[0245] X 1 X 2 X 3 Indicates -CO-O-, -O-CO-, or a single bond.

[0246] Z 1 Represents -O-, -CO-, -C(R) y R z - or -CF2CF2-,

[0247] Z 2 Z 3 This indicates -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CF2O-, -OCF2-, or -(CH2). n - where n is 2, 3, or 4.

[0248] L represents F, Cl, CN, or a straight-chain or branched alkyl, alkoxy, alkenyl, alkynyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy, or alkoxycarbonyloxy group having 1-12 carbon atoms, optionally mono- or polyfluorinated.

[0249] L' and L" represent H, F, or Cl,

[0250] r represents 0, 1, 2, 3, or 4.

[0251] s represents 0, 1, 2, or 3.

[0252] t represents 0, 1, or 2.

[0253] x represents 0 or 1.

[0254] Compounds of formulas M2 and M13 are particularly preferred.

[0255] Further preferred are tri-reactive compounds M15 to M30, particularly M17, M18, M19, M22, M23, M24, M25, M29 and M30.

[0256] In compounds of formulas M1 to M30, the group

[0257] Preferred

[0258] Wherein L has the same or different meanings given above or below each time it appears, and is preferably F, Cl, CN, NO2, CH3, C2H5, C(CH3)3, CH(CH3)2, CH2CH(CH3)C2H5, OCH3, OC2H5, COCH3, COC2H5, COOCH3, COOC2H5, CF3, OCF3, OCHF2, OC2F5 or P-Sp-, very preferably F, Cl, CN, CH3, C2H5, OCH3, COCH3, OCF3 or P-Sp-, more preferably F, Cl, CH3, OCH3, COCH3 or OCF3, especially F or CH3.

[0259] Preferred compounds of formulas M1-M30 are those in which P 1 P 2 and P 3 The group can be acrylate, methacrylate, oxobutyl, or epoxy, with acrylate or methacrylate being the most preferred.

[0260] Further preferred compounds of formulas M1-M30 are those in which Sp 1 Sp 2 and Sp 3Those that are single keys.

[0261] Further preferred compounds of formulas M1-M30 are those in which Sp 1 Sp 2 and Sp 3 One of them is a single bond and Sp 1 Sp 2 and Sp 3 The other one is different from those with single bonds.

[0262] Further preferred compounds of formulas M1-M30 are those Sp groups that are different from single bonds. 1 Sp 2 and Sp 3 It represents -(CH2) s1 Those with -X"-, where s1 is an integer from 1 to 6, preferably 2, 3, 4 or 5, and X" is a connection to the benzene ring and is -O-, -O-CO-, -CO-O, -O-CO-O- or a single bond.

[0263] Particularly preferred are LC media containing one, two, or three polymerizable compounds of Formula I.

[0264] Further preferred are polymerizable compounds selected from formulas RM-1 to RM-83 in Table D below.

[0265] The proportion of the compound of Formula I in the LC medium is preferably 0.01-5%, very preferably 0.05-1%, and most preferably 0.1-0.5%.

[0266] It has been observed that the combination of polymerizable compounds of formulas M1-M30 with compounds of formulas C, P, T, and D results in favorable behavior of the LC dielectric, enabling rapid and complete polymerization, fast production of low tilt angles (stable after UV exposure), high reliability and high VHR value along with high birefringence after UV exposure. Furthermore, the LC dielectric exhibits high absorption at longer UV wavelengths, allowing for the use of such longer UV wavelengths for polymerization, which is advantageous for display manufacturing processes.

[0267] In order to manufacture a PSA display, a polymerizable compound contained in an LC medium is polymerized or crosslinked in situ between the substrates of the LC display, optionally simultaneously applying voltage to the electrodes (if a compound contains two or more polymerizable groups).

[0268] The structure of the PSA display according to the invention corresponds to the typical geometry of a PSA display, as described in the prior art cited at the beginning. A geometry without protrusions is preferred, particularly those in which the electrodes on the color filter side are unstructured and only the electrodes on the TFT side have slots. A particularly suitable and preferred electrode structure for a PS-VA display is described, for example, in US 2006 / 0066793 A1.

[0269] The preferred PSA-type LC display of the present invention includes:

[0270] - A first substrate, comprising a pixel electrode defining a pixel region (the pixel electrode is connected to a switching element disposed in each pixel region and optionally includes a microslit pattern), and optionally a first alignment layer disposed on the pixel electrode.

[0271] - A second substrate, comprising a conventional electrode layer (which may be disposed on the entire portion of the second substrate facing the first substrate), and an optional second alignment layer.

[0272] - An LC layer disposed between the first and second substrates and comprising an LC medium, the LC medium comprising a polymerizable component A and a liquid crystal component B as described in the context, wherein the polymerizable component A may also be polymerizable.

[0273] The first and / or second alignment layer controls the alignment orientation of the LC molecules in the LC layer. For example, in a PS-VA display, the alignment layer is selected to impart vertical (or perpendicular) alignment (i.e., perpendicular to the surface) or tilted alignment to the LC molecules. Such an alignment layer may, for example, contain polyimide, which may also be rubbed or prepared by photoalignment methods.

[0274] An LC layer with an LC dielectric can be deposited between the substrates of a display using methods commonly used by display manufacturers, such as a drop-fill (ODF) method. The polymerizable components of the LC dielectric are then polymerized, for example, by UV photopolymerization. This polymerization can be carried out in one step or in two or more steps.

[0275] A PSA display may include other components such as color filters, black matrices, passivation layers, optical delay layers, transistor elements for addressing individual pixels, etc., all of which are well known to those skilled in the art and can be used without creative skill.

[0276] Those skilled in the art can design the electrode structure depending on the individual display type. For example, for a PS-VA display, the multi-domain orientation of LC molecules can be initiated by providing electrodes with slits and / or protrusions or projections to generate two, four or more different tilted alignment directions.

[0277] During polymerization, the polymerizable compound forms a cross-linked polymer, which causes a certain pretilt of LC molecules in the LC medium. Without being bound by specific theories, it is believed that at least a portion of the cross-linked polymer formed by the polymerizable compound will separate from the phase or precipitate from the LC medium, forming a polymer layer on the substrate or electrode, or on an alignment layer provided thereon. Microscopic measurements (such as SEM and AFM) have confirmed that at least a portion of the formed polymer accumulates at the LC / substrate interface.

[0278] Polymerization can be carried out in one step. Alternatively, polymerization can be carried out first in the first step (optionally with voltage applied simultaneously) to create a pretilt angle, and then polymerized or crosslinked in a second polymerization step without voltage applied (“final curing”) of compounds that did not react in the first step.

[0279] Suitable and preferred polymerization methods are, for example, thermal or photopolymerization, preferably photopolymerization, especially UV-induced photopolymerization, which can be achieved by exposing the polymerizable compound to UV radiation.

[0280] Optionally, one or more polymerization initiators may be added to the LC medium. Suitable conditions for polymerization and suitable types and amounts of initiators are known to those skilled in the art and described in the literature. Commercially available photoinitiators are suitable for free radical polymerization. or (Ciba AG). If a polymerization initiator is used, its proportion is preferably 0.001 to 5% by weight, particularly preferably 0.001 to 1% by weight.

[0281] The polymerizable compounds according to the invention are also suitable for initiator-free polymerization, which comes with considerable advantages, such as low material costs and, in particular, less LC media contamination due to possible residual initiators or their degradation products. Polymerization can therefore be carried out without the addition of an initiator. In a preferred embodiment, the LC medium therefore does not contain a polymerization initiator.

[0282] LC media may also contain one or more stabilizers to prevent undesirable spontaneous polymerization of RM, such as during storage or transportation. Suitable types and amounts of stabilizers are known to those skilled in the art and are described in the literature. Particularly suitable stabilizers include, for example, commercially available... Stabilizers for series (Ciba AG), such as 1076. If a stabilizer is used, the proportion of the stabilizer is preferably 10-500,000 ppm, particularly preferably 50-50,000 ppm, based on the total amount of the RM or polymerizable component (component A).

[0283] The polymerizable compounds of Formula I do indeed exhibit particularly good UV absorption, and are therefore particularly suitable for manufacturing methods of PSA displays that include one or more of the following characteristics:

[0284] - In a display, a polymerizable medium is exposed to UV light in a two-step process, comprising a first UV exposure step (“UV-1 step”) to create a tilt angle, and a second UV exposure step (“UV-2 step”) to complete the polymerization.

[0285] - In an LC display, the polymerizable medium is exposed to UV light generated by an energy-efficient UV lamp (also known as a "green UV lamp"). These lamps are characterized by relatively low intensity in their absorption spectrum of 300-380 nm (1 / 100-1 / 10 of that of a conventional UV1 lamp), and they are preferably used in the UV2 step, but are also optionally used in the UV1 step when avoiding high intensity is necessary for the method.

[0286] - In the display, the polymerizable medium is exposed to UV light generated by a UV lamp, which has a radiation spectrum shifted to a longer wavelength (preferably 340 nm or longer) to avoid the short UV light exposure in the PS-VA method.

[0287] Both low-intensity and UV light shifted to longer wavelengths are used to protect the organic layer from potential damage caused by UV light.

[0288] Preferred embodiments of the present invention relate to a method for manufacturing a PSA display as described in the context, comprising one or more of the following features:

[0289] - The polymerizable LC medium is exposed to UV light in a 2-step process, which includes a first UV exposure step (“UV-1 step”) to create a tilt angle, and a second UV exposure step (“UV-2 step”) to complete the polymerization.

[0290] -Polymerizable LC media exposed to UV lamps with a power of 0.5 mW / cm² 2 Up to 10mW / cm 2 UV light with an intensity in the wavelength range of 300-380 nm is preferably used in the UV2 step, and optionally also in the UV1 step.

[0291] - The polymerizable LC medium can be exposed to UV light with a wavelength of 340 nm or longer, and preferably 400 nm or shorter.

[0292] This preferred method can be carried out, for example, by using a desired UV lamp, or by using a bandpass filter and / or a cutoff filter that is substantially transmissive to UV light with its respective desired wavelength and substantially blocks UV light with its respective undesired wavelength. For example, when radiation of UV light with a wavelength λ of 300-400 nm is desired, UV exposure can be carried out using a wideband pass filter that is substantially transmissive to wavelengths of 300 nm < λ < 400 nm. When radiation of UV light with a wavelength λ greater than 340 nm is desired, UV exposure can be carried out using a cutoff filter that is substantially transmissive to wavelengths of λ > 340 nm.

[0293] "Substantially transmits" means that the filter transmits most, preferably at least 50%, of the intensity of the incident light at the desired wavelength. "Substantially blocks" means that the filter does not transmit most, preferably at least 50%, of the intensity of the incident light at the undesired wavelength. "Desired (undesired) wavelength" refers, for example, to wavelengths within (outside) a given λ range in the case of a bandpass filter, and to wavelengths above (below) a given λ value in the case of a cutoff filter.

[0294] This preferred method makes it possible to manufacture displays using longer UV wavelengths, thereby reducing or even avoiding the harmful and damaging effects of short UV light components.

[0295] UV radiation energy is typically 6 to 100 J, depending on the production method and conditions.

[0296] The LC medium according to the invention is indeed substantially composed of polymerizable component A and LC component B (or LC bulk mixture) as described in the context. However, the LC medium may additionally contain one or more other components or additives, preferably selected from substances including but not limited to: comonomers, chiral dopants, polymerization initiators, inhibitors, stabilizers, surfactants, wetting agents, lubricants, dispersants, hydrophobic agents, binders, flow improvers, defoamers, degassing agents, diluents, reactive diluents, auxiliaries, colorants, dyes, pigments, and nanoparticles.

[0297] Preferably, the polymerizable component A) is composed solely of formula I. * LC media composed of polymerizable compounds.

[0298] In another preferred embodiment, besides formula I * In addition to the compounds, polymerizable component A) also contains one or more other polymerizable compounds (“comonomers”), preferably selected from RM.

[0299] The proportion of polymerizable component A) in the LC medium is preferably >0 to <5%, very preferably >0 to ≤1%, and most preferably 0.01-0.5%.

[0300] The proportion of LC component B in the LC medium is preferably 95% to <100%, and very preferably 99% to <100%.

[0301] In addition to the polymerizable component A) as described above, the LC medium according to the invention also comprises LC component B), or an LC body mixture containing one or more, preferably two or more, LC compounds selected from non-polymerizable low molecular weight compounds. These LC compounds are selected such that they are stable and / or non-reactive to the polymerization reaction under the conditions applied to the polymerization of polymerizable compounds.

[0302] Examples of these compounds are those with the formulas CY and PY above.

[0303] Preferably, the LC medium in which the LC component (B) or the LC bulk mixture has a phase-type LC phase and preferably does not have a chiral liquid crystal phase is an LC medium.

[0304] Further preferred are achiral compounds of formula I, and LC media in which components A and / or B are selected only from achiral compounds.

[0305] LC component B), or LC main mixture, preferably a phase-type LC mixture.

[0306] The LC dielectric and LC component B) or LC bulk mixture of the present invention preferably have negative dielectric anisotropy. Such LC dielectrics are particularly suitable for use in PS-VA, PS-IPS and PS-UB-FFS displays or in related modes using LC materials with Δε<0.

[0307] The LC dielectric and LC bulk mixture of the present invention preferably have a negative dielectric anisotropy Δε of -0.5 to -10, particularly -2.5 to -7.5, at 20°C and 1 kHz.

[0308] The LC medium and LC host mixture of the present invention preferably have a nematic phase range of ≥120K, and very preferably ≥130K.

[0309] The LC medium and LC bulk mixture of the present invention preferably have a rotational viscosity of ≤250 mPa·s at 20°C, and very preferably ≤200 mPa·s.

[0310] The birefringence Δn of the LC medium and the LC bulk mixture of the present invention is preferably less than 0.16, very preferably 0.06 to 0.14, and most preferably 0.07 to 0.12.

[0311] The particularly preferred embodiments of such LC media are those of portions a) to z1):

[0312] a) An LC medium in which component B) or the LC bulk mixture further comprises one or more compounds of the following formula:

[0313]

[0314] Each of the groups has the following meaning:

[0315] express

[0316] express

[0317] R 3 and R 4 Each of these terms independently represents an alkyl group having 1 to 12 carbon atoms, wherein 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.

[0318] Z y It represents -CH2CH2-, -CH=CH-, -CF2O-, -OCF2-, -CH2O-, -OCH2-, -CO-O-, -O-CO-, -C2F4-, -CF=CF-, -CH=CH-CH2O- or a single bond, with single bonds being preferred.

[0319] Compounds of formula ZK are preferably selected from the following sub-formulas:

[0320]

[0321]

[0322] Among them alkyl and alkyl * Each of these terms independently represents 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-.

[0323] Compounds of formulas ZK1, ZK2, ZK5, and ZK6 are highly preferred. Compounds of formulas ZK1 and ZK6 are most preferred.

[0324] The particularly preferred ZK compounds are selected from the following sub-formulas:

[0325]

[0326]

[0327] Among them, propyl, butyl, and pentyl are straight-chain groups.

[0328] The most preferred compound is the one of formula ZK1a.

[0329] Preferably, component B) contains 5% to 40%, very preferably 15% to 40%, of a compound of formula ZK, preferably selected from formulas ZK1, ZK2, ZK5 and ZK6, very preferably formulas ZK1 and ZK6.

[0330] Preferably, component B contains 1 to 5, most preferably 1 to 3, compounds of formula ZK or its sub-formulas.

[0331] Preferably, component B) contains only compounds of formula ZK, wherein R 3 and R 4 It indicates an alkyl or alkoxy group having 1 to 12 carbon atoms.

[0332] b) LC media in which component B) or the LC bulk mixture contains one or more compounds selected from formulas CY and PY:

[0333]

[0334] Each group is defined as in formulas C and P.

[0335] 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.

[0336] Compounds of formula CY are preferably selected from the following sub-formulas:

[0337]

[0338]

[0339]

[0340] Among them alkyl and alkyl *Each of these terms independently represents 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, with (O) representing 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-.

[0341] Compounds selected from the formulas CY1, CY2, CY9, CY10, CY20 and CY21 are highly preferred.

[0342] PY compounds are preferably selected from the following sub-formulas:

[0343]

[0344]

[0345] Among them alkyl and alkyl * Each of these terms independently represents 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, with (O) representing 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-.

[0346] Compounds selected from formulas PY1 and PY2 are highly preferred.

[0347] Preferably, the concentration of compounds of formula CY and PY and their derivatives in the LC medium is less than 5%.

[0348] In another preferred embodiment of the invention, the LC medium does not contain compounds of the formula CY or PY.

[0349] c) wherein component B) or the LC host mixture comprises one or more mesocrystalline or LC compounds containing alkenyl groups (hereinafter also referred to as "alkenyl compounds") in an LC medium, wherein the alkenyl groups are stable to the polymerization reaction under the conditions for polymerization of polymerizable compounds contained in the LC medium.

[0350] Preferably, component B) or the LC bulk mixture comprises one or more alkenyl compounds selected from formulas AN and AY.

[0351]

[0352]

[0353] Each group, when appearing in the same or different manner and independently of the others, has the following meaning:

[0354] express

[0355] express

[0356] express

[0357] R A1 It is an alkenyl group having 2 to 9 carbon atoms, or if at least one of rings X, Y, and Z represents a cyclohexenyl group, it also has R. A2 One of the meanings,

[0358] R A2 It is an alkyl group having 1 to 12 carbon atoms, wherein one or two non-adjacent CH2 groups may be replaced by -O-, -CH=CH-, -CO-, -OCO-, or -COO- in a manner in which the O atoms are not directly connected to each other.

[0359] Z x The bond type can be -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.

[0360] L 1,2 The components are H, F, Cl, OCF3, CF3, CH3, CH2F, or CHF2H, with H, F, or Cl being preferred.

[0361] x is 1 or 2.

[0362] z is 0 or 1.

[0363] Preferred compounds of formula AN and AY are those in which R A2 Those selected from vinyl, propenyl, butenyl, pentenyl, hexenyl, and heptenyl.

[0364] In a preferred embodiment, component B) or the LC bulk mixture comprises one or more compounds selected from the formula AN:

[0365]

[0366]

[0367] Among them alkyl and alkyl * Each of these terms independently represents a straight-chain alkyl group having 1 to 6 carbon atoms, and alkenyl and alkenyl * Each of these independently represents a straight-chain alkenyl group having 2 to 7 carbon atoms. alkenyl and alkenyl * The preferred representations are 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-.

[0368] Preferably, component B) or the LC main mixture contains one or more compounds selected from formulas AN1, AN2, AN3 and AN6, and very preferably one or more compounds of formula AN1.

[0369] In another preferred embodiment, component B) or the LC bulk mixture comprises one or more compounds selected from the following formulas:

[0370]

[0371]

[0372] Where m represents 1, 2, 3, 4, 5, or 6, i represents 0, 1, 2, or 3, and R b1 It represents H, CH3, or C2H5.

[0373] In another preferred embodiment, component B) or the LC bulk mixture comprises one or more compounds selected from the following formulas:

[0374]

[0375] The most preferred compounds are those of formulas AN1a2 and AN1a5.

[0376] In another preferred embodiment, component B) or the LC bulk mixture comprises one or more compounds selected from the following formulas:

[0377]

[0378]

[0379]

[0380]

[0381]

[0382] Among them alkyl and alkyl * Each of these terms independently represents a straight-chain alkyl group having 1 to 6 carbon atoms, "(O)" represents an O- atom or a single bond, and alkenyl and alkenyl * Each of these independently represents a straight-chain alkenyl group having 2 to 7 carbon atoms. alkenyl and alkenyl * The preferred representations are 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-.

[0383] In another preferred embodiment, component B) or the LC bulk mixture comprises one or more compounds selected from the following formulas:

[0384]

[0385]

[0386] Where m and n each independently represent 1, 2, 3, 4, 5 or 6, and alkenyl 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-.

[0387] Preferably, the concentration of compounds of formula AN and AY and their derivatives in the LC medium is less than 5%.

[0388] In another preferred embodiment of the invention, the LC medium does not contain compounds of formula AN or AY.

[0389] d) LC media in which component B) or the LC bulk mixture further comprises one or more compounds of the following formula:

[0390]

[0391] Each of the groups has the following meaning:

[0392] d represents en.

[0393] At least one of the rings F is different from the subcyclohexyl group.

[0394] f represents 1 or 2.

[0395] R 1 and R 2 Each of these terms independently represents an alkyl group having 1 to 12 carbon atoms, wherein one or two non-adjacent CH2 groups may be replaced by -O-, -CH=CH-, -CO-, -OCO-, or -COO- in a manner in which the O atoms are not directly connected to each other.

[0396] Z x It represents -CH2CH2-, -CH=CH-, -CF2O-, -OCF2-, -CH2O-, -OCH2-, -CO-O-, -O-CO-, -C2F4-, -CF=CF-, -CH=CH-CH2O- or a single bond, with single bonds being preferred.

[0397] L 1 and L 2 Each of them independently represents F, Cl, OCF3, CF3, CH3, CH2F, and CHF2.

[0398] Preferably, the group L 1 and L 2 Both represent F or the L group. 1 and L 2 One of them represents F and the other represents Cl.

[0399] Compounds of formula LY are preferably selected from the following sub-formulas:

[0400]

[0401]

[0402]

[0403]

[0404]

[0405] 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, particularly 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-.

[0406] In another preferred embodiment of the invention, the LC medium does not contain the LY compound.

[0407] e) wherein component B) or the LC bulk mixture further comprises one or more compounds selected from the following LC media:

[0408]

[0409] Where alkyl represents C 1-6 -alkyl, L x The symbol represents H or F, and X represents F, Cl, OCF3, OCHF2, or OCH=CF2. Compounds of formula G1, wherein X represents F, are particularly preferred.

[0410] f) Wherein component B) or the LC bulk mixture further comprises one or more compounds selected from the following LC media:

[0411]

[0412]

[0413]

[0414] 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 C 1-6 -alkoxy or C 2-6 -Alkenyl, d is preferably 1. The LC medium of the present invention preferably contains ≥5% by weight of one or more of the above-described compounds.

[0415] g) An LC medium further comprising one or more biphenyl compounds selected from the following formula:

[0416]

[0417] Among them alkyl and alkyl * Each of these terms independently represents a straight-chain alkyl group having 1 to 6 carbon atoms, and alkenyl and alkenyl *Each of these independently represents a straight-chain alkenyl group having 2 to 6 carbon atoms. alkenyl and alkenyl * The preferred representations are 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-.

[0418] Compound B2 is particularly preferred.

[0419] Compounds of formulas B1 to B3 are preferably selected from the following sub-formulas:

[0420]

[0421] alkyl * This refers to an alkyl group having 1 to 6 carbon atoms. The media of the present invention particularly preferably comprise one or more compounds of the formula B1a and / or B2c.

[0422] h) Wherein component B) or the LC bulk mixture further comprises one or more tetraphenyl compounds selected from the following:

[0423]

[0424] in

[0425] R Q It is an alkyl, alkoxy, oxalyl, or alkoxyalkyl group having 1 to 9 carbon atoms, or an alkenyl or alkenyloxy group having 2 to 9 carbon atoms, all of which may optionally be fluorinated.

[0426] X Q It is F, Cl, a haloalkyl or alkoxy group having 1 to 6 carbon atoms, or a haloalkenyl or alkenoxy group having 2 to 6 carbon atoms.

[0427] L Q1 To L Q6 H or F are independent of each other, where L Q1 To L Q6 At least one of them is F.

[0428] The preferred compound of formula Q is wherein R Q This refers to those straight-chain alkyl groups having 2 to 6 carbon atoms (preferably ethyl, n-propyl, or n-butyl).

[0429] The preferred compound of formula Q is wherein L Q3 and L Q4 Those are those of F. Other preferred compounds of formula Q are L. Q3 L Q4 and LQ1 and L Q2 Those in which one or both are F.

[0430] The preferred compound of formula Q is wherein X is Q Those that represent F or OCF3 (F is highly preferred).

[0431] Compound Q is preferably selected from the following sub-formulas.

[0432]

[0433] Where R Q It has one of the meanings of formula Q or one of its preferred meanings given in the context, and is preferably ethyl, n-propyl or n-butyl.

[0434] Particularly preferred are compounds of formula Q1, especially those wherein R Q Those are the n-propyl ones.

[0435] Preferably, the proportion of compound Q in the LC medium is >0 to ≤5% by weight, very preferably 0.1% to 2% by weight, and most preferably 0.2% to 1.5% by weight.

[0436] Preferably, the LC medium contains 1 to 5, more preferably 1 or 2, compounds of formula Q.

[0437] Adding a tetraphenyl compound of formula Q to the LC medium mixture reduces ODF inhomogeneity while maintaining high UV absorption, enabling rapid and complete polymerization, strong and rapid generation of tilt angles, and increasing the UV stability of the LC medium.

[0438] Furthermore, adding a compound of formula Q with positive dielectric anisotropy to an LC dielectric with negative dielectric anisotropy allows for better control of the dielectric constants ε|| and ε ⊥ The value of ε is particularly made possible by achieving a high dielectric constant ε|| while maintaining a constant dielectric anisotropy Δε, thereby reducing kick-back voltage and image lag.

[0439] i) Wherein component B) or the LC bulk mixture further comprises one or more CP compounds in the LC medium:

[0440]

[0441] Where R C The designation indicates an alkyl, alkoxy, oxalyl, or alkoxyalkyl group having 1 to 9 carbon atoms, or an alkenyl or alkenyloxy group having 2 to 9 carbon atoms, all of which may optionally be fluorinated.

[0442] X CThis indicates F, Cl, a halogenated alkyl or alkoxy group having 1 to 6 carbon atoms, or a halogenated alkenyl or alkenyloxy group having 2 to 6 carbon atoms.

[0443] L C1 L C2 H or F can be represented independently of each other, where L C1 and L C2 At least one of them is F.

[0444] The preferred CP compound is one in which R C This refers to those straight-chain alkyl groups having 2 to 6 carbon atoms (preferably ethyl, n-propyl, or n-butyl).

[0445] The preferred CP compound is wherein L C1 and L C2 Those that are F.

[0446] The preferred CP compound is one in which X C Those that represent F or OCF3 (F is highly preferred).

[0447] The preferred CP compound is selected from the following formula

[0448]

[0449] Where R C It has one of the meanings of formula CP or one of its preferred meanings given by the context, and is preferably ethyl, n-propyl or n-butyl, very preferably n-propyl.

[0450] Preferably, the proportion of the CP compound in the LC medium is >0 to ≤10% by weight, very preferably 0.1% to 8% by weight, and most preferably 0.2% to 5% by weight.

[0451] Preferably, the LC medium contains 1 to 5, more preferably 1, 2 or 3 CP compounds.

[0452] Adding a CP compound with positive dielectric anisotropy to an LC dielectric with negative dielectric anisotropy allows for better control of the dielectric constants ε|| and ε ⊥ The value of the additive C compound is particularly advantageous because it enables the achievement of a high dielectric constant ε|| while maintaining a constant dielectric anisotropy Δε, thereby reducing recoil voltage and image viscosity. Furthermore, the addition of the C compound reduces the viscosity and reaction time of the LC dielectric.

[0453] k) wherein component B) or the LC bulk mixture further comprises one or more compounds selected from the following LC media:

[0454]

[0455]

[0456] Where R 1 and R 2 Having 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.

[0457] Preferably, component B) contains one or more compounds selected from formula O1, O3 and O4, with very preferred formula O1.

[0458] l) Wherein component B) or the LC bulk mixture further comprises one or more compounds of the following formula:

[0459]

[0460] in

[0461] express

[0462]

[0463] R 9 (F) represents an optional fluorine substituent, and q represents 1, 2, or 3, and R 7 With R 1 One of the meanings indicated is that the amount is preferably >3% by weight, particularly ≥5% by weight, and very particularly preferably 5% to 30% by weight.

[0464] The particularly preferred FI compounds are selected from the following sub-formulas:

[0465]

[0466]

[0467] Where R 7 Preferably, it represents a straight-chain alkyl group, and R 9 It represents CH3, C2H5, or n-C3H7. Compounds of formula FI1, FI2, and FI3 are particularly preferred.

[0468] m) wherein component B) or the LC bulk mixture further comprises one or more compounds selected from the following LC media:

[0469]

[0470] Where R 8 With R 1 The meaning indicated is as follows, and alkyl means a straight-chain alkyl group having 1 to 6 carbon atoms.

[0471] n) Wherein component B) or the LC body mixture further comprises one or more compounds containing tetrahydronaphthyl or naphthyl units, for example, compounds selected from the following formula:

[0472]

[0473]

[0474]

[0475] in

[0476] R 10 and R 11 Each of these terms independently represents an alkyl group having 1 to 12 carbon atoms, wherein one or two non-adjacent CH2 groups may be replaced by -O-, -CH=CH-, -CO-, -OCO-, or -COO- in a manner in which the O atoms are not directly connected to each other, preferably alkyl or alkoxy groups having 1 to 6 carbon atoms.

[0477] 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.

[0478] And 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.

[0479] o) Wherein component B) or the LC bulk mixture further comprises one or more of the following difluorodibenzo-p-methyl and / or methylated LC media:

[0480]

[0481]

[0482] Where R 11 and R 12 Each of them independently possesses the characteristics described above for R. 11 One of the meanings indicated is

[0483] Ring M represents trans-1,4-cyclohexene or 1,4-phenylene.

[0484] Zm It can be -C2H4-, -CH2O-, -OCH2-, -CO-O-, or -O-CO-.

[0485] c is 0, 1, or 2.

[0486] The amount is preferably 3% to 20% by weight, and particularly 3% to 15% by weight.

[0487] The particularly preferred compounds of formula BC, CR, and RC are selected from the following sub-formulas:

[0488]

[0489]

[0490]

[0491]

[0492] Among them alkyl and alkyl * Each of these terms independently represents a straight-chain alkyl group having 1 to 6 carbon atoms, (O) representing an oxygen atom or a single bond, and c being 1 or 2. (The last two characters, "alkenyl" and "alkenyl", appear to be unrelated to the preceding text and are likely separate entries.) * Each of these independently represents a straight-chain alkenyl group having 2 to 6 carbon atoms. alkenyl and alkenyl * The preferred representations are 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-.

[0493] A mixture comprising one, two, or three BC-2 compounds is highly preferred.

[0494] p) Wherein component B) or the LC bulk mixture further comprises one or more fluorinated phenanthrenes and / or dibenzofurans of the following formula:

[0495]

[0496] Where R 11 and R 12 Each of them independently possesses the characteristics described above for R. 11 One of the indicated meanings is that b represents 0 or 1, L represents F, and r represents 1, 2, or 3.

[0497] The particularly preferred PH and BF compounds are selected from the following sub-formulas:

[0498]

[0499] R and R' each independently represent a straight-chain alkyl or alkoxy group having 1 to 7 carbon atoms.

[0500] q) LC media in which component B) or the LC bulk mixture further comprises one or more monocyclic compounds of the following formula.

[0501]

[0502] Where R 1 and R 2 Each of these terms independently represents an alkyl group having 1 to 12 carbon atoms, wherein one or two non-adjacent CH2 groups may be replaced by -O-, -CH=CH-, -CO-, -OCO-, or -COO- in a manner in which the O atoms are not directly connected to each other, preferably alkyl or alkoxy groups having 1 to 6 carbon atoms.

[0503] L 1 and L 2 Each of them independently represents F, Cl, OCF3, CF3, CH3, CH2F, and CHF2.

[0504] 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.

[0505] Compound Y is preferably selected from the following sub-formulas:

[0506]

[0507]

[0508] Among them, Alkyl and Alkyl * Each of these terms independently represents 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 of these terms independently represents a straight-chain alkenyl group having 2 to 6 carbon atoms, with O representing an oxygen atom or a single bond. Alkenyl and Alkenyl * The preferred representations are 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-.

[0509] The particularly preferred compound Y is selected from the following formula:

[0510]

[0511]

[0512] Alkoxy preferably refers to a straight-chain alkoxy group having 3, 4, or 5 carbon atoms.

[0513] In another preferred embodiment of the invention, the LC medium does not contain compound Y.

[0514] r) An LC medium comprising 1 to 5, preferably 1, 2 or 3 polymerizable compounds selected from Formula I or its subforms.

[0515] s)LC medium, wherein the polymerizable compound of formula I or its sub-formulas is present in the overall mixture at a proportion of 0.05% to 5%, preferably 0.1% to 1%.

[0516] t) The following LC media: free from compounds having terminal vinyloxy groups (-O-CH=CH2) except for the polymerizable compounds in component A), and particularly free from R... A1 or R A2 Compounds of the formula AN or AY that represent or contain a terminal vinyloxy group (-O-CH=CH2).

[0517] u) The following LC media: except for the polymerizable compounds of component A), it does not contain compounds containing vinyl groups, and in particular, it does not contain compounds of the form AN or AY.

[0518] v) LC media containing compounds that do not contain the formula CY or PY.

[0519] w) The following LC media: except for the polymerizable compounds of formula I, do not contain compounds containing diphenylacetylene groups; specifically, the LC host mixture or component B does not contain compounds containing diphenylacetylene groups. The term "diphenylacetylene group" means a group of the following formula.

[0520]

[0521] The benzene ring is optionally substituted with, for example, an F atom.

[0522] x) The following LC media: except for the polymerizable compounds of Formula I, do not contain compounds containing four or more rings, and in particular, the LC host mixture or component B does not contain compounds containing four or more rings (e.g., benzene rings or cyclohexyl rings).

[0523] y) The following LC medium: wherein component B) or the LC main mixture contains at least one compound of formula C, at least one compound of formula P, at least one compound of formula T, at least one compound of formula D wherein e is 1, and preferably at least one compound of formula ZK.

[0524] z) The following LC medium: wherein component B) or the LC bulk mixture is substantially composed of compounds selected from formulas C, P, T, D (where e is preferably 1) and ZK and optional O1, preferably composed only of such compounds, particularly wherein these compounds are selected from the preferred formulas and concentration ranges disclosed above.

[0525] z1) LC media containing a compound of formula D in which e is 1.

[0526] The combination of the compounds of the preferred embodiments mentioned above with the aforementioned polymeric compounds results in a low threshold voltage, low rotational viscosity, and very good low-temperature stability in the LC medium according to the invention, while also exhibiting constant high-definition bright spots and a high HR value, and allowing for rapid establishment of a particularly low pretilt angle in PSA displays. In particular, compared to media from the prior art, the LC medium exhibits a significantly shorter response time (especially grayscale response time) in PSA displays.

[0527] In the VA-type display according to the present invention, the molecules in the LC dielectric layer are aligned perpendicularly to the electrode surface or have an inclined vertical alignment in the switched-off state. When a voltage is applied to the electrode, the LC molecules re-align, and the longitudinal molecular axis becomes parallel to the electrode surface.

[0528] The LC medium according to the invention may also contain other additives known to those skilled in the art and described in the literature, such as polymerization initiators, inhibitors, stabilizers, surfactants, or chiral dopants. These additives may be polymerizable or non-polymerizable. Polymerizable additives are therefore classified as polymerizable components or component A). Non-polymerizable additives are therefore classified as non-polymerizable components or component B.

[0529] In a preferred embodiment, the LC medium contains one or more chiral dopants, the concentration of which is preferably from 0.01% to 1%, and very preferably from 0.05% to 0.5%. The chiral dopants are preferably selected from the group consisting of compounds in Table B below, and very preferably from the group consisting of R- or S-1011, R- or S-2011, R- or S-3011, R- or S-4011 and R- or S-5011.

[0530] In another preferred embodiment, the LC medium comprises a racemic mixture of one or more chiral dopants (preferably selected from the chiral dopants mentioned in the preceding paragraphs).

[0531] In addition, 0 to 15% by weight of a pleochroic dye, nanoparticles, conductive salts, preferably ammonium ethyl dimethyl dodecyl 4-hexyloxybenzoate, ammonium tetrabutyltetraphenylborate, or complex salts of crown ethers can be added to the LC medium (see, for example, Haller et al., Mol. Cryst. Liq. Cryst.). 24 , 249-258 (1973)) are used to improve conductivity, or to add substances for modifying the dielectric anisotropy, viscosity and / or orientation of the nematic phase. Such substances are described, for example, in DE-A 22 09 127, 22 40 864, 23 21 632, 23 38 281, 24 50 088, 26 37 430 and 28 53 728.

[0532] The individual components of the preferred embodiments a)-z) of the LC media according to the invention are known, or the methods for preparing them can be obtained from the prior art by those skilled in the art, as they are based on standard methods described in the literature. For example, compounds of the corresponding formula CY are described in EP-A-0 364 538. For example, compounds of the corresponding formula ZK are described in DE-A-26 36 684 and DE-A-33 21 373.

[0533] The LC media usable according to the invention are prepared in a conventional manner, for example by mixing one or more of the above-described compounds with one or more polymerizable compounds as defined above, and optionally with other liquid crystal compounds and / or additives. Generally, the desired amount of the component used in a small amount is dissolved in the component constituting the main component, advantageously at high temperature. The solution of the component can also be mixed in an organic solvent (e.g., acetone, chloroform, or methanol), and the solvent is removed, for example, by distillation after thorough mixing. Furthermore, the invention relates to a method for preparing the LC media of the invention.

[0534] It will be self-evident to those skilled in the art that the LC medium according to the present invention may also contain, for example, compounds in which H, N, O, Cl, and F are replaced by corresponding isotopes such as deuterium.

[0535] The following examples illustrate the invention but do not limit it. However, they demonstrate to those skilled in the art the preferred mixture concept, the preferred compounds used and their respective concentrations, and combinations thereof. Furthermore, the examples clarify which properties and combinations of properties are available.

[0536] Use the following abbreviations:

[0537] (n, m, z: independently of each other in each case, are 1, 2, 3, 4, 5, or 6) Table A

[0538]

[0539]

[0540]

[0541]

[0542]

[0543]

[0544]

[0545]

[0546]

[0547]

[0548]

[0549]

[0550]

[0551]

[0552]

[0553]

[0554]

[0555]

[0556]

[0557]

[0558]

[0559]

[0560] In a preferred embodiment of the invention, the LC medium of the invention comprises one or more compounds selected from the group consisting of compounds from Table A.

[0561] Table B

[0562] Table B shows feasible chiral dopants that can be added to the LC media of the present invention.

[0563]

[0564]

[0565] The LC medium preferably contains 0% to 10% by weight, particularly 0.01% to 5% by weight, and especially preferably 0.1% to 3% by weight of dopant. The LC medium preferably contains one or more dopant selected from the group consisting of compounds listed in Table B.

[0566] Table C

[0567] Table C shows feasible stabilizers that can be added to LC media.

[0568] (Here, n represents an integer from 1 to 12, preferably 1, 2, 3, 4, 5, 6, 7, or 8; the terminal methyl group is not shown.)

[0569]

[0570]

[0571]

[0572]

[0573]

[0574]

[0575] 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 a stabilizer. The LC medium preferably contains one or more stabilizers selected from the group consisting of compounds listed in Table C.

[0576] Table D

[0577] Table D shows exemplary compounds that can be used in the LC media of the present invention, preferably as reactive mesocrystalline compounds.

[0578]

[0579]

[0580]

[0581]

[0582]

[0583]

[0584]

[0585]

[0586]

[0587]

[0588] In a preferred embodiment of the invention, the mesocrystalline medium comprises one or more compounds selected from the group consisting of compounds in Table D. Very preferably, the LC medium comprises compounds selected from formulas RM-1 to RM-32, most preferably RM-1, RM-15 or RM-17, or compounds selected from formulas RM-41 to RM-48, most preferably RM-41.

[0589] In addition, the following abbreviations and symbols are used:

[0590] V0 represents the threshold voltage at 20℃, capacitive [V].

[0591] n e This indicates the unusual refractive index at 20°C and 589 nm.

[0592] n o This represents the ordinary refractive index at 20°C and 589 nm.

[0593] △n represents the optical anisotropy at 20℃ and 589nm.

[0594] ε⊥ represents the dielectric constant perpendicular to the director at 20℃ and 1kHz.

[0595] ε || This represents the dielectric constant parallel to the director at 20℃ and 1kHz.

[0596] Δε represents the dielectric anisotropy at 20℃ and 1kHz.

[0597] cl.p., Tni indicates clearing point, phase type - isotropic phase [°C],

[0598] γ1 represents the rotational viscosity [mPa•s] at 20℃.

[0599] K1 represents the elastic constant at 20℃, and the "oblique stretching" deformation [pN].

[0600] K2 represents the elastic constant at 20℃, and the "torsional" deformation [pN].

[0601] K3 represents the elastic constant at 20°C, and the bending deformation [pN].

[0602] Unless otherwise stated, all concentrations in this specification are expressed as weight percentages and refer to the entire mixture in question, including all solid or liquid crystal components, but excluding solvents.

[0603] Unless otherwise stated, all temperature values ​​indicated in this application, such as melting point T(C,N), transformation from smectic (S) to nematic (N) T(S,N), and clearing point T(N,I), are expressed in degrees Celsius (°C). Mp represents the melting point, and cl.p. = clearing point. Furthermore, C = liquid crystal phase, N = nematic phase, S = smectic phase, and I = isotropic phase. The data between these symbols represent the transformation temperature.

[0604] All physical properties are and have been determined according to “Merck Liquid Crystals, Physical Properties of Liquid Crystals” Status November 1997, Merck KGaA, Germany, and are applicable to a temperature of 20°C, with Δn measured at 589 nm and Δε measured at 1 kHz, unless otherwise explicitly stated in each case.

[0605] The term "threshold voltage" used in this invention refers to the capacitive threshold (V0), which is also known as the Freedericks threshold, unless otherwise stated. In embodiments, the optical threshold is also, as is generally the case, for 10% relative contrast (V0). 10 (This is given.)

[0606] Unless otherwise stated, the method of polymerizing polymerizable compounds in a PSA display as described in the context, wherein the LC medium is in the form of a liquid crystal phase, preferably a nematic phase, is carried out at a temperature, and most preferably at room temperature.

[0607] Unless otherwise stated, the preparation of test kits and the measurement of their photoelectric and other properties are carried out by the methods described below or similar methods.

[0608] The display used to measure capacitive threshold voltage consists of two planar parallel glass outer plates spaced 25 μm apart. Each outer plate has an electrode layer on the inside and an unrubbed polyimide alignment layer on the top, which results in vertical edge alignment of liquid crystal molecules.

[0609] The display or test box used to measure the tilt angle consists of two parallel glass outer plates spaced 4 μm apart. Each outer plate has an electrode layer on the inside and a polyimide alignment layer on the top. The two polyimide layers are antiparallel and rub against each other, resulting in vertical edge alignment of the liquid crystal molecules.

[0610] Polymerizable compounds are polymerized in a display or test chamber by irradiating the chamber with UVA light of a defined intensity for a predetermined time while a voltage (typically 10V to 30V AC, 1kHz) is applied to the display. In embodiments, unless otherwise specified, a metal halide lamp and a 50mW / cm² voltage are used. 2 The intensity was used for polymerization. This intensity was measured using a standard UVA meter (a high-end Hoenle UV meter with a UVA sensor).

[0611] The tilt angle was determined by a crystal rotation experiment (Autronic-Melchers TBA-105). Here, a low value (i.e., a large offset relative to a 90° angle) corresponds to a large tilt.

[0612] The VHR value was measured as follows: 0.2% of the polymerizable monomer compound was added to the LC bulk mixture, and the resulting mixture was introduced into a VA-VHR test chamber comprising an unrubbed VA-polyimide alignment layer. The thickness d of this LC layer was approximately 6 μm, unless otherwise specified. The VHR value was determined before and after UV exposure at a pulse of 1V, 60Hz, and 64μs (measurement instrument: Autronic-Melchers VHRM-105).

[0613] Comparative Example 1

[0614] The nematic LC bulk mixture C1 is prepared as follows.

[0615]

[0616] The mixture has a Tni of <100℃.

[0617] Comparative Example 2

[0618] The nematic LC bulk mixture C2 is prepared as follows.

[0619]

[0620]

[0621] The mixture has a Tni of <100℃.

[0622] Example 1

[0623] The nematic LC bulk mixture N1 is prepared as follows.

[0624]

[0625] The mixture has a high Tni >100℃.

[0626] Example 2

[0627] The nematic LC bulk mixture N2 is prepared as follows.

[0628]

[0629]

[0630] The mixture has a high Tni >100℃.

[0631] Example 3

[0632] The nematic LC bulk mixture N3 is prepared as follows.

[0633]

[0634] The mixture has a high Tni >100℃.

[0635] Example 4

[0636] The nematic LC bulk mixture N4 is prepared as follows.

[0637]

[0638] The mixture has a high Tni >100℃.

[0639] Example 5

[0640] The nematic LC bulk mixture N5 is prepared as follows.

[0641]

[0642]

[0643] The mixture has a high Tni >100℃.

[0644] Application Examples

[0645] The polymerizable mixtures P1, P2, P3, P4 and P5 of the present invention were prepared by adding 0.2 wt% of reactive mesomorphic M1 to nematic LC host mixtures N1, N2, N3, N4 and N5, respectively.

[0646] For comparative purposes, polymerizable mixtures CP1 and CP2 were prepared by adding 0.2 wt% of reactive mesomorphic M1 to nematic LC host mixtures C1 and C2, respectively.

[0647]

[0648] The Tni values ​​of polymerizable mixtures P1-P5, CP1 and CP2 are the same as those of the corresponding bulk mixtures N1-N5, C1 and C2.

[0649] The VHR values ​​of the polymerizable mixture were measured before and after UV exposure to a C-type fluorescent UV lamp (305 nm to 355 nm) for 40 min or 80 min at 20 °C or 60 °C.

[0650] The VHR values ​​of polymerizable mixtures are shown in Table 1.

[0651] Table 1 - VHR Values

[0652]

[0653]

[0654] As can be seen from Table 1, compared with polymerizable mixtures CP1 and CP2, polymerizable mixtures P1-P5 of the present invention show similar or slightly higher VHR values ​​after UV exposure.

[0655] Each of the polymerizable mixtures and the polymerizable comparative mixtures of the present invention is inserted into a VA e / o test chamber. The test chamber contains a VA-polyimide alignment layer (JALS-2096-R1) with antiparallel friction. The LC layer thickness d is approximately 4 μm.

[0656] To determine the polymerization rate, after polymerization occurred in the test chamber through UV exposure at 60°C for 80 min using a type C fluorescent UV lamp (305 nm to 355 nm), the residual content of unpolymerized RM in the test chamber was measured by HPLC (in weight %). The polymerization mixture was rinsed out of the test chamber using MEK (methyl ethyl ketone) and then measured.

[0657] The residual concentration of RM in the mixture after irradiation for 40 min or 80 min is shown in Table 2.

[0658] Table 2 - Residual monomer content

[0659]

[0660] As can be seen from Table 2, the polymerizable mixtures P1-P5 of the present invention exhibit rapid polymerization, and the amount of residual RM is only slightly higher than that of polymerizable mixtures CP1 and CP2.

[0661] Using 50mW / cm 2The pretilt angle was determined by crystal rotation experiment (Autronic-Melchers TBA-105) before and after UV irradiation with a high-pressure Hg lamp for 120 s (6 J) or 240 s (10 J). The pretilt angles are shown in Table 3.

[0662] Table 3 - Pretilt Angle

[0663]

[0664] As can be seen from Table 3, the polymerizable mixtures P1-P5 of the present invention exhibit pretilt angles comparable to those of polymerizable mixtures CP1 and CP2.

[0665] The above results show that, compared with polymerizable mixtures CP1 and CP2, polymerizable mixtures P1-P5 of the present invention exhibit significantly higher clearing temperatures Tni than polymerizable mixtures CP1 and CP2, while still enabling the achievement of good PSA device properties, such as high reliability after UV exposure, high VHR value, rapid pretilt angle generation, and rapid and complete polymerization.

Claims

1. A liquid crystal (LC) medium comprising... - Polymerizable component A), comprising one or more polymerizable compounds, and - Liquid crystal component B), comprising one or more mesocrystalline or liquid crystal compounds, wherein the compounds comprise one or more compounds selected from formulas C, P, T and D. Each group, when appearing in the same or different manner and independently of the others, has the following meaning: for for for e is 1 or 2 R 1 and R 2 It is an alkyl group having 1 to 12 carbon atoms, wherein 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. R 5 and R 6 It is an alkyl group having 1 to 12 carbon atoms, wherein 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. Z x and Z y For -CH2CH2-, -CH=CH-, -CF2O-, -OCF2-, -CH2O-, -OCH2-, -CO-O-, -O-CO-, -C2F4-, -CF=CF-, -CH=CH-CH2O-, or single bonds. L 1-4 For F or Cl, L T1 -L T6 It is H, F or Cl, where L T1 To L T6 At least one of them is F or Cl. Its features The following conditions must be met: Component B) contains ≥60% compounds selected from formulas C, P, T, and D. Component B) contains ≥50% compounds selected from formulas C, P, and T. Component B) contains ≥40% compounds selected from formulas C and P, wherein R 2 It is an alkoxy group having 1 to 12 carbon atoms. Component B) contains 1% to 20% of a compound of formula D, where e is 1. The LC medium contains at least 31% of a compound of formula C, wherein R 2 It is an alkoxy group having 1 to 12 carbon atoms. The compound of formula C is characterized by being selected from the following sub-formulas: Where a represents 2, alkyl, and alkyl * Each of these terms independently represents 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, with (O) representing an oxygen atom or a single bond. The compound P is selected from the following sub-formulas: Among them alkyl and alkyl * Each of these terms independently represents 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, with (O) representing an oxygen atom or a single bond. The compound of formula T is selected from the following sub-formulas: Where R represents a straight-chain alkyl or alkoxy group having 1 to 7 carbon atoms, R * This indicates a straight-chain alkenyl group with 2 to 7 carbon atoms, (O) represents an oxygen atom or a single bond, and m represents an integer from 1 to 6. The nematic phase range of this LC medium is ≥130K.

2. The LC medium according to claim 1, characterized in that... Compound D is selected from the following sub-formulas: Among them alkyl and alkyl * Each of these terms independently represents 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.

3. The LC medium according to any one of claims 1 to 2, characterized in that... Component B) further comprises one or more compounds of the following formula. Each of the groups has the following meaning: express express R 3 and R 4 Each of these terms independently represents an alkyl group having 1 to 12 carbon atoms, wherein 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. Z y It represents -CH2CH2-, -CH=CH-, -CF2O-, -OCF2-, -CH2O-, -OCH2-, -CO-O-, -O-CO-, -C2F4-, -CF=CF-, -CH=CH-CH2O-, or a single bond.

4. The LC medium according to any one of claims 1 to 2, characterized in that... Component B) further comprises one or more compounds of formula O1. Where R 1 and R 2 As defined in claim 1.

5. The LC medium according to any one of claims 1 to 2, characterized in that... The polymerizable compound is selected from formula I. R a -B 1 -(Z b -B 2 ) m -R b I Each group, when appearing in the same or different manner and independently of the others, has the following meaning: R a and R b It is P, P-Sp-, H, F, Cl, Br, I, -CN, -NO2, -NCO, -NCS, -OCN, -SCN, SF5, or a straight-chain or branched alkyl group having 1 to 25 C atoms, wherein, in addition, one or more non-adjacent CH2 groups may be independently coupled to each other in a manner in which the O and / or S atoms are not directly connected to each other. 0 )=C(R 00 )-、-C≡C-、-N(R 00 -, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-, -O-CO-O-, and in addition, one or more H atoms may be replaced by F, Cl, Br, I, CN, P or P-Sp-, wherein if B 1 and / or B 2 If it contains saturated C atoms, then R a and / or R b It can also represent a group that is spirotropically attached to this saturated C atom. Wherein group R a and R b At least one of them represents or contains the group P or P-Sp-, P is a polymerizable group. Sp can be a spacer group or a single bond. B 1 and B 2 It is an aromatic, heteroaromatic, alicyclic, or heterocyclic group, which may also contain a fused ring, and it is unsubstituted or mono- or polysubstituted. Z b is -O-, -S-, -CO-, -CO-O-, -OCO-, -O-CO-O-, -OCH2-, -CH2O-, -SCH 2- , -CH2S-, -CF2O-, -OCF2-, -CF2S-, -SCF2-, -(CH2) n1 -, -CF2CH2-, -CH2CF2-, -(CF2) n1 -, -CH=CH-, -CF=CF-, -C≡C-, -CH=CH-COO-, -OCO-CH=CH-, CR 0 R 00 Or a single key, R 0 and R 00 It is H or an alkyl group having 1 to 12 carbon atoms. m can be 0, 1, 2, 3, or 4. n1 is 1, 2, 3, or 4. L is P, P-Sp-, OH, CH2OH, F, Cl, Br, I, -CN, -NO2, -NCO, -NCS, -OCN, -SCN, -C(=O)N(R x )2、-C(=O)Y 1 -C(=O)R x -N(R) x 2. Optionally substituted silyl, optionally substituted aryl having 6 to 20 carbon atoms, or straight-chain or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy, or alkoxycarbonyloxy having 1 to 25 carbon atoms, wherein one or more H atoms may be substituted with F, Cl, P, or P-Sp-. Y 1 Halogen, R x It is a P, P-Sp-, H, halogen, straight-chain, branched, or cyclic alkyl group having 1 to 25 C atoms, wherein one or more non-adjacent CH2 groups may be replaced by -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-, or -O-CO-O- in a manner in which O and / or S atoms are not directly connected to each other, and wherein one or more H atoms may be replaced by F, Cl, P, or P-Sp-, an optionally substituted aryl or aryloxy group having 6 to 40 C atoms, or an optionally substituted heteroaryl or heteroaryloxy group having 2 to 40 C atoms.

6. The LC medium according to claim 5, characterized in that... B 1 and B 2 It is an aromatic, heteroaromatic, alicyclic, or heterocyclic group having 4 to 25 ring atoms, and may also contain fused rings, and is unsubstituted or monosubstituted or polysubstituted.

7. The LC medium according to any one of claims 1 to 2, characterized in that... The polymerizable compound is selected from the following formula: Each group, when appearing in the same or different manner and independently of the others, has the following meaning: P 1 P 2 P 3 The radicals are vinyloxy, acrylate, methacrylate, fluoroacrylate, chloroacrylate, oxetyl, or epoxy groups. Sp 1 Sp 2 Sp 3 It is a single bond or a spacer group, wherein in addition, the group P 1 -Sp 1 -、P 1 -Sp 2 -and P 3 -Sp 3 One or more of them can also represent R. aa The premise is that the group P exists. 1 -Sp 1 -、P 2 -Sp 2 and P 3 -Sp 3 - at least one of them is related to R aa different, R aa It is H, F, Cl, CN, or a straight-chain or branched alkyl group having 1 to 25 C atoms, wherein, in addition, one or more non-adjacent CH2 groups may be independently coupled to each other in a manner in which the O and / or S atoms are not directly connected to each other. 0 )=C(R 00 )-、-C≡C-、-N(R 0 -, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-, -O-CO-O-, and in addition, one or more H atoms can be replaced by F, Cl, CN or P. 1 -Sp 1 -Alternative, R 0 R 00 It is H or an alkyl group having 1 to 12 carbon atoms. R y and R z It can be H, F, CH3 or CF3. X 1 X 2 X 3 It can be -CO-O-, -O-CO-, or a single bond. Z 1 -O-, -CO-, -C(R) y R z - or -CF2CF2-, Z 2 Z 3 It can be -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CF2O-, -OCF2-, or -(CH2). n - where n is 2, 3, or 4. L is F, Cl, CN, or a straight or branched chain having 1 to 12 C atoms, optionally monofluorinated or polyfluorinated alkyl, alkoxy, alkenyl, alkynyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyl, or alkoxycarbonyloxy. L' and L” represent H, F, or Cl. r can be 0, 1, 2, 3, or 4. s is 0, 1, 2 or 3. t is 0, 1, or 2. x is 0 or 1.

8. The LC medium according to any one of claims 1 to 2, characterized in that... Component B) consists essentially of compounds selected from formulas C, P, T, D and ZK as defined in claims 1 to 4 and optionally O1.

9. The LC medium according to any one of claims 1 to 2, characterized in that... The polymerizable compound is polymerized.

10. An LC display comprising an LC medium as defined in any one of claims 1 to 9.

11. The LC display of claim 10, wherein it is a PSA type display.

12. The LC display of claim 11, wherein it is a PS-VA, PS-IPS or PS-UB-FFS display.

13. The LC display of claim 12, wherein the LC medium has a nematic phase range of ≥130K.

14. The LC display according to any one of claims 11 to 13, characterized in that... It comprises two substrates, electrodes provided on each substrate or two electrodes provided on only one of the substrates, and a layer of LC dielectric as defined in any one of claims 1 to 9 located between the substrates, wherein at least one substrate is transparent to light, and wherein the polymerizable compound is polymerized between the substrates of the display.

15. A method for producing an LC display according to claim 14, comprising the following steps: An LC medium as defined in any one of claims 1 to 9 is provided between the substrates of the display, and a polymerizable compound is polymerized.

Images