TWI663250B - Liquid-crystal medium and liquid-crystal display - Google Patents

Abstract

The present invention relates to LC media; its preparation method; and its use for optical, electro-optical, and electronic purposes, in particular to LC displays, and in particular to PS (polymer stabilized) or PSA (polymer continuous alignment) LC displays. use.

Description

Liquid crystal medium and liquid crystal display

The present invention relates to an LC medium; a method for preparing the same; and its use for optical, electro-optical, and electronic purposes, specifically LC displays, especially PS (polymer stabilized) or PSA (polymer continuous alignment) type LC displays.

Vertical alignment units have been widely used in liquid crystal display (LCD) devices due to their excellent contrast ratio. In normal incidence, the contrast ratio is not sensitive to the incident light wavelength, LC cell gap, and operating temperature. The LC unit of a VA display contains a layer of liquid crystal (LC) medium between two transparent electrodes, where the LC medium usually has a negative dielectric (DC) anisotropy. In the off state, the molecules of the LC layer are aligned perpendicular to the electrode surface (vertically) or have an oblique vertical alignment. After applying a voltage to the electrode, realignment of the LC molecules parallel to the electrode surface occurs.

It was further developed as a so-called PS (Polymer Stabilized) display, which is also known under the term "PSA" (Polymer Continuous Alignment). In these displays, a small amount (for example, 0.3% by weight, usually <1% by weight) of a polymerizable compound is added to the LC medium, and after being introduced into the LC unit, it is usually polymerized by UV light under a voltage applied between the electrodes. To polymerize or crosslink in situ. The addition of a polymerizable mesogen or a liquid crystal compound (also known as a "reactive mesogen" (RM)) to an LC mixture has proven particularly suitable. At the same time, the PSA principle is being used in different classic LC displays. Therefore, for example, PSA-VA, PSA-OCB, PS-IPS / FFS and PS-TN displays are known.

PSA-VA displays are described in, for example, JP 10-036847 A, EP 1 170 626 A2, EP 1 378 557 A1, EP 1 498 468 A1, US 2004/0191428 A1, US 2006/0066793 A1, and US 2006/0103804 A1. PSA-OCB displays are described, for example, in T.-J-Chen et al., Jpn.J.Appl.Phys.45, 2006,2702-2704 and SHKim, L.-C-Chien, Jpn.J.Appl.Phys. 43,2004,7643-7647. PS-IPS displays are described, for example, in US 6,177,972 and Appl. Phys. Lett. 1999, 75 (21), 3264. PS-TN displays are described in, for example, Optics Express 2004, 12 (7), 1221.

In particular, for monitors and especially TV applications, there is a continuing need to optimize the response time and contrast and brightness (and therefore the transmittance) of LC displays. The PSA approach here offers key advantages.

The direct method to shorten the response time is to reduce the LC cell gap while using a higher birefringent LC mixture in order to maintain the necessary phase delay. In this connection, the liquid crystal drip (ODF) method allows a thinner cell gap (d <4 μm) to be made while maintaining a high manufacturing yield. According to the ODF method disclosed in US 2003-0147040 A1, for example, the LC material is directly dropped on the first substrate, and then the LC unit and the second substrate are assembled.

However, it is widely known by experts that a drop mura defect may occur when manufacturing a PSA display panel. For example, US 8,501,286 B2 discloses that when the cell gap of a PSA-VA display is changed to less than 3.8 μm, it causes the reactive monomers in the LC mixture to not be widely dispersed in a larger area on the polyimide surface of the alignment film. And therefore, different amounts of reactive monomers of the LC mixture are unevenly deposited on the polyimide (PI) surface of the alignment film. To solve this problem, the author recommends using the following RM:

It goes without saying, however, that the limited use of such compounds is a severe limitation for the development of further mixtures.

Another suggested solution to the above problem is disclosed in KR 2011-0068303. Among them, the author proposes a liquid crystal mixture containing an additive for reducing the surface tension of the LC mixture. Suggested additives include silicone-based compounds such as polydimethylsiloxane (poly-dimethylsiloxane or PDMS). However, no details are disclosed regarding the additives used and suitable liquid crystal mixture compositions.

Therefore, there is still a great need for PSA displays, especially VA-type PSA displays, and alternative LC media for such displays, which do not have the disadvantages described above or have only a small degree of disadvantages described above and have Improved characteristics. In particular, there is an extreme need for PSA displays and materials for PSA displays that promote high specific resistance while promoting large operating temperature ranges, short response times (even at low temperatures) and low threshold voltages, low pretilt, gray Degree of diversity, high contrast and wide viewing angle, and has a high voltage retention rate (VHR) after UV exposure.

Therefore, the present invention has the following objective: to provide novel and suitable materials for PSA displays, especially VA-type PSA displays, which do not have the disadvantages indicated above or only to a lesser extent the disadvantages indicated above, as fast as possible And it is fully aggregated to achieve a lower pretilt to be established, reduce or prevent dripping dead pixels in the display, and at the same time better promote very high specific resistance values, lower threshold voltages and shorter response times.

Surprisingly, the inventors have discovered that the requirements defined above can be achieved by an LC medium comprising one or more non-polymerizable mesogen compounds, one or more polymerizable mesogen compounds and one or more compounds of formula I and Can overcome the disadvantages of the mentioned prior art LC media,

Wherein R ^a represents hydrogen or a hydrocarbon having 1 to 20 carbon atoms; preferably, a linear or branched alkylene group having 1 to 20 carbon atoms, wherein one or more non-terminal CH ₂ groups may The way that O atoms are not directly connected to each other is replaced by -O-, -NH-, -CH = CH-, -CONH-, -CO-, -OCO-, or -COO-, with an extension of 3 to 8 carbon atoms Cycloalkyl or aryl having 6 to 10 carbon atoms in which a hydrogen atom can be replaced by a halogen or a hydrocarbon group having 1 to 4 carbon atoms, such as phenyl, benzyl, methylphenyl, or methoxy Phenyl, R ^c represents a hydrocarbon having 1 to 20 carbon atoms; preferably a straight or branched chain alkylene having 1 to 20 carbon atoms, in which one or more non-terminal CH ₂ groups can make The O atoms are not directly connected to each other by -O-, -NH-, -CH = CH-, -CONH-, -CO-, -OCO-, or -COO-, and the ring has 3 to 8 carbon atoms. Alkyl or aryl having 6 to 10 carbon atoms in which a hydrogen atom can be replaced by a halogen, or a hydrocarbon group having 1 to 4 carbon atoms such as phenyl, benzyl, methylphenyl, or methoxy phenyl, R ^b, and R ^d represents hydrogen or alkyl having from 1 to 8 Hydrocarbon atoms, preferably a hydrogen, a linear or branched chain of 1 to 4 carbon atoms in the alkylene group, wherein the -CH ₂ - can manner that O atoms are not directly connected to each other via the -O -, - NH-, -CH = CH -, - CONH - , - CO -, - OCO- or -COO- substitution, Z ^a represents a single bond or -O-, and n is an integer of 0 to 10, preferably 0,1,2 , 3

In addition, the present invention relates to the use of LC media according to the present invention in PS and PSA displays, especially in PSA-VA displays containing LC media by polymerizing polymerizable mesogen in situ in PSA displays under the application of an electric or magnetic field. Base compounds for use in LC media Uses for tilt angle.

In addition, the present invention relates to an LC display, especially a PS or PSA display, and more preferably a PSA-VA display, containing an LC medium according to the present invention.

In addition, the present invention relates to a PS or PSA type LC display, particularly a PSA-VA display, including an LC unit. The LC unit is composed of two substrates, at least one of which is transparent and at least one of which has an electrode layer. The LC dielectric layer comprising a polymerizing component and a low molecular weight component is located between the substrates, wherein the polymerizing component can polymerize one or more polymerizable mesogens between the substrates of the LC units in the LC medium under an applied voltage. Based compounds.

In addition, the present invention relates to a method for preparing an LC medium as described above and below by mixing one or more non-polymerizable mesogen compounds, one or more polymerizable mesogen compounds, and one or more compounds of formula I.

In addition, the present invention relates to a method for producing an LC display, particularly a PSA-VA display, as described above and below, by mixing one or more non-polymerizable mesogens, one or more polymerizable mesogens And one or more organosilicon compounds of Formula I or its respective subformula, and other liquid crystal compounds and / or additives as appropriate, the LC material is directly dropped on the substrates before assembling the two substrates, and the two substrates are assembled, and The polymerizable mesogen compound is polymerized under an applied voltage.

Definitions and terms

Unless otherwise indicated, the term "PSA" is used to refer to both PS displays and PSA displays.

As used herein, the terms "tilt" and "tilt angle" mean the tilted alignment of the LC molecules of the LC medium relative to the surface of the cell in an LC display (here preferably a PSA display). The inclination angle here means the average angle (<90 °) between the longitudinal molecular axis of the LC molecule (LC director) and the surface of the plane-parallel outer plate forming the LC unit. A low tilt angle value (that is, a large deviation from an angle of 90 °) here corresponds to a large tilt. Suitable for measuring tilt angle in the example method. Unless otherwise indicated, the tilt angle values disclosed above and below are related to this measurement method.

The term "liquidyl group" or "liquidyl group" as used herein is known to those skilled in the art and described in the literature, and means basically due to the anisotropy of its attractive and repulsive interactions This group contributes to the generation of liquid crystal (LC) phase groups in low molecular weight or polymeric substances. The compound containing a mesogen group (the mesogen compound) itself does not necessarily have to have an LC phase. It is also possible for the mesogen compound to exhibit LC phase behavior only after mixing with other compounds and / or after polymerization. Typical mesogen groups are, for example, rigid rod-shaped or disc-shaped cells.

An overview of the terms and definitions used in connection with mesogen or LC compounds is given in Pure Appl. Chem. 73 (5), 888 (2001) and C. Tsuchierske, G. Pelzl, S. Diele, Angew. Chem. 2004, 116 Given in 6340-6368.

As used herein, the terms "polymerizable mesogen", "reactive mesogen" and "RM" mean a compound containing one mesogen group and one or more functional groups suitable for polymerization, The latter is also called "polymerizable group" or "P".

Unless otherwise stated, the term "polymerizable compound" as used below means a polymerizable monomer compound.

As used herein, the terms "low molecular weight compound" and "non-polymerizable mesogenic compound" mean a mesogenic compound, usually a monomeric mesogenic compound, which is commonly used under conditions known to those skilled in the art, especially It does not contain functional groups suitable for polymerization under the conditions used for polymerizing RM.

As used herein, the terms "active layer" and "switchable layer" mean a layer in an electro-optical display (e.g., an LC display) that contains one or more molecules having structural and optical anisotropy, such as, for example, LC Molecules, which change their orientation after an external stimulus (such as an electric or magnetic field), resulting in a change in the layer's transmittance to polarized or unpolarized light.

The "organic group" above and below means a carbon group or a hydrocarbon group.

"Carbon-based" means a monovalent or polyvalent organic group containing at least one carbon atom, wherein this does not contain other atoms (such as -C≡C-) or optionally contains one or more other atoms, such as N, O, S , P, Si, Se, As, Te, or Ge (for example, carbonyl, etc.).

The term "hydrocarbyl" refers to a carbon group that additionally contains one or more H atoms and optionally one or more heteroatoms (such as N, O, S, P, Si, Se, As, Te or Ge).

The carbon or hydrocarbon group may be a saturated or unsaturated group. Unsaturated groups are, for example, aryl, alkenyl or alkynyl. The carbon or hydrocarbon group having more than 3 C atoms may be linear, branched, and / or cyclic, and may also contain a spiro bond or a condensed ring.

The terms "alkyl", "aryl", "heteroaryl" and the like also encompass polyvalent groups such as alkylene, aryl, heteroaryl, and the like.

The term "aryl" means an aromatic carbon group or a group derived therefrom.

In this connection, the structural formula Has with The same expression.

The term "heteroaryl" refers to an "aryl" as defined above containing one or more heteroatoms.

Preferred carbon and hydrocarbon groups are optionally substituted alkyl, alkenyl, alkynyl, alkoxy, alkylcarbonyl groups having 1 to 40, preferably 1 to 25, and particularly preferably 1 to 18 C atoms. , Alkoxycarbonyl, alkylcarbonyloxy and alkoxycarbonyloxy, optionally substituted aryl or aryloxy groups having 6 to 40, preferably 6 to 25 C atoms, or optionally Substituted alkaryl, aralkyl, alkylaryloxy, arylalkoxy, arylcarbonyl, aryloxycarbonyl, arylcarbonyloxy groups having 6 to 40, preferably 6 to 25 C atoms And aryloxycarbonyloxy.

More preferred carbon and hydrocarbon groups are C ₁ -C ₄₀ alkyl, C ₂ -C ₄₀ alkenyl, C ₂ -C ₄₀ alkynyl, C ₃ -C ₄₀ allyl, C ₄ -C ₄₀ alkyldienyl , C ₄ -C ₄₀ polyalkenyl, C ₆ -C ₄₀ aryl, C ₆ -C ₄₀ alkylaryl, C ₆ -C ₄₀ aralkyl, C ₆ -C ₄₀ alkylaryloxy, C _6- C ₄₀ arylalkoxy, C ₂ -C ₄₀ heteroaryl, C ₄ -C ₄₀ cycloalkyl, C ₄ -C ₄₀ cycloalkenyl, and the like. Particularly preferred are C ₁ -C ₂₂ alkyl, C ₂ -C ₂₂ alkenyl, C ₂ -C ₂₂ alkynyl, C ₃ -C ₂₂ allyl, C ₄ -C ₂₂ alkyldienyl, C _6- C ₁₂ aryl, C ₆ -C ₂₀ aralkyl and C ₂ -C ₂₀ heteroaryl.

More preferred carbon and hydrocarbon groups are straight, branched or cyclic alkyl groups having 1 to 40, preferably 1 to 25 C atoms, which are unsubstituted or monosubstituted by F, Cl, Br, I or CN Or multiple substitutions, and in which one or more non-adjacent CH ₂ groups can make the O atom and / or S atom not directly connected to each other independently of each other via -C (R ^x ) = C (R ^x )- -C≡C-, -N (R ^x )-, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O- substitution.

R ^x preferably represents H, halogen, straight chain, branched chain, or cyclic alkyl group having 1 to 25 C atoms. In addition, one or more non-adjacent C atoms may be -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O-, and one or more of the H atoms may be substituted by fluorine, optionally 6 to 40 C atoms Aryl or aryloxy or optionally substituted heteroaryl or heteroaryloxy having 2 to 40 C atoms.

Preferred alkoxy groups are, for example, methoxy, ethoxy, 2-methoxyethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, second butoxy, Tertiary butoxy, 2-methylbutoxy, n-pentoxy, n-hexyloxy, n-heptyloxy, n-octyloxy, n-nonoxy, n-decoxy, n-undecyloxy, N-dodecyloxy and the like.

Preferred alkyl groups are, for example, methyl (Me), ethyl (Et), n-propyl, isopropyl, n-butyl, isobutyl, second butyl, third butyl, 2-methylbutyl , N-pentyl, second pentyl, cyclopentyl, n-hexyl, cyclohexyl, 2-ethylhexyl, n-heptyl, cycloheptyl, n-octyl, cyclooctyl, n-nonyl, n-decyl, N-undecyl, n-dodecyl, dodecyl, trifluoromethyl, perfluoro-n-butyl, 2,2,2-trifluoroethyl, perfluorooctyl, perfluorohexyl, and the like.

Preferred alkenyl groups are, for example, vinyl, propenyl, butenyl, pentenyl, cyclopentenyl, hexenyl, cyclohexenyl, heptenyl, cycloheptenyl, octenyl, cyclooctene Base etc.

Preferred alkynyl is, for example, ethynyl, propynyl, butynyl, pentynyl, hexynyl, octynyl, and the like.

Preferred alkoxy groups are, for example, methoxy (OMe), ethoxy (OEt), 2-methoxyethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, Second butoxy, third butoxy, 2-methylbutoxy, n-pentoxy, n-hexyloxy, n-heptyloxy, n-octyloxy, n-nonoxy, n-decoxy, n- Undecyloxy, n-dodecyloxy and the like.

Preferred amino groups are, for example, dimethylamino, methylamino, methylphenylamino, phenylamino and the like.

Aryl and heteroaryl groups can be monocyclic or polycyclic, that is, they can contain one ring (e.g., phenyl) or two or more rings, and these rings can also be fused (e.g., naphthalene Group) or covalently bonded (e.g., biphenyl), or a combination containing fused and bonded rings. Heteroaryl contains one or more heteroatoms preferably selected from O, N, S and Se.

Particularly preferred are monocyclic, bicyclic or tricyclic aryl groups having 6 to 25 C atoms and monocyclic, bicyclic or tricyclic heteroaryl groups having 5 to 25 ring atoms, which optionally contain fused rings and optionally To replace. In addition, a 5-membered, 6-membered or 7-membered aryl group and a heteroaryl group are preferred. In addition, one or more CH groups may pass through the N, S, Or O replacement.

Preferred aryl groups are, for example, phenyl, biphenyl, bitriphenyl, [1,1 ': 3', 1 "] bitriphenyl-2'-yl, naphthyl, anthracene, binaphthyl, phenanthrene, 9, 10-dihydro-phenanthrene, polonium, dihydropyrene, , Acene, tetracene, pentacene, benzofluorene, pyrene, indene, indenefluorene, spirobifluorene, and the like.

Preferred heteroaryl groups are, for example, 5-membered rings such as pyrrole, pyrazole, imidazole, 1,2,3-triazole, 1,2,4-triazole, tetrazole, 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 ring, Such as pyridine, pyridazine, pyrimidine, pyrazine, 1,3,5-triazine, 1,2,4-triazine, 1,2,3-triazine, 1,2,4,5-tetrazine, 1 , 2,3,4-tetrazine, 1,2,3,5-tetrazine; or condensing groups such as indole, isoindole, indazine, indazole, benzimidazole, benzotriazole, Purine, naphthalimidazole, fimidazole, pyrimidazole, pyrazine imidazole, quinazoline imidazole, benzoxazole, naphthoxazole, anthraxazole, phenanthrazole, isoxazole, benzothiazole, benzo Furan, isobenzofuran, dibenzofuran, quinoline, isoquinoline, pyridine, benzo-5,6-quinoline, benzo-6,7-quinoline, benzo-7,8-quine Phthaloline, benzoisoquinoline, acridine, phenothiazine, phenoxazine, benzopyrazine, benzopyrimidine, quinoxaline, phenazine, Pyridine, azacarbazole, benzocarboline, phenanthrene, morpholine, thieno [2,3b] thiophene, thieno [3,2b] thiophene, dithienothiophene, isobenzothiophene, dibenzothiophene Benzothiadiazolothiophene or a combination of these groups.

The aryl and heteroaryl groups mentioned above and below may also be alkyl, alkoxy, sulfanyl, fluorine, fluoroalkyl or other aryl or heteroaryl groups, such as benzyl, methylbenzene And methoxyphenyl.

(Non-aromatic) alicyclic and heterocyclic groups encompass both saturated rings (ie, those rings containing only single bonds) and partially unsaturated rings (ie, those rings that may also contain multiple bonds). The heterocyclic ring contains one or more heteroatoms preferably selected from Si, O, N, S and Se.

(Non-aromatic) cycloaliphatic and heterocyclic groups may be monocyclic, that is, contain only one ring (e.g., cyclohexane); or polycyclic, that is, contain multiple rings (e.g., decahydro) Naphthalene or bicyclooctane). Especially preferred is a saturated group. Further, a monocyclic, bicyclic or tricyclic group having 5 to 25 ring atoms is preferred, which optionally contains a fused ring and is optionally substituted. In addition, it is preferably a 5-membered, 6-membered, 7-membered, or 8-membered carbocyclic group. In addition, one or more C atoms may be substituted by Si and / or one or more CH groups may be substituted by N and / or one. One or more non-adjacent CH ₂ groups may be replaced by -O- and / or -S-.

Preferred alicyclic and heterocyclic groups are, for example, 5-membered groups such as cyclopentane, tetrahydrofuran, tetrahydrothiofuran, pyrrolidine; 6-membered groups such as cyclohexane, cyclohexylsilane, cyclohexene , Tetrahydropiperan, tetrahydrothiopiperan, 1,3-dioxane, 1,3-dithiane, piperidine; 7-membered groups such as cycloheptane; and fused groups such as tetra Hydronaphthalene, decahydronaphthalene, indan, bicyclo [1.1.1] pentane-1,3-diyl, bicyclo [2.2.2] octane-1,4-diyl, spiro [3.3] heptane-2 , 6-diyl, octahydro-4,7-methyl bridge indane-2,5-diyl.

Preferred substituents are, for example, groups that promote solubility, such as alkyl or alkoxy groups; Electronic groups, such as fluorine, nitro or nitrile; or substituents used to increase the glass transition temperature (Tg) in polymers, especially bulky groups, such as third butyl or optionally substituted aryl.

Preferred substituents, also referred to as "L" above and below, are, for example, F, Cl, Br, I, -CN, -NO ₂ , -NCO, -NCS, -OCN, -SCN, -C (= O ) N (R ^x ) ₂ , -C (= O) Y ¹ , -C (= O) R ^x , -N (R ^x ) ₂ , where R ^x has the meaning indicated above, and Y ¹ represents halogen ; Optionally substituted aryl groups having 6 to 40, preferably 6 to 20 C atoms; and straight or branched chain alkyl groups, alkoxy groups, alkylcarbonyl groups, alkane groups having 1 to 25 C atoms An oxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy group in which one or more H atoms are optionally replaced by F or Cl.

"Substituted aryl" preferably means via halogen, -CN, R ⁰ , -OR ⁰ , -CO-R ⁰ , -CO-OR ⁰ , -O-CO-R ⁰ or -O-CO-OR ⁰ substitution, where R ⁰ has the meaning indicated above.

Particularly preferred substituents L are, for example, F, Cl, CN, NO ₂ , CH ₃ , C ₂ H ₅ , OCH ₃ , OC ₂ H ₅ , COCH ₃ , COC ₂ H ₅ , COOCH ₃ , COOC ₂ H ₅ , CF ₃ , OCF ₃ , OCHF ₂ , OC ₂ F ₅ and phenyl.

Preferably or Where L has one of the meanings indicated above.

The term "halogen" means F, Cl, Br or I.

-CO-, -C (= O)-, and -C (O)-represent carbonyl groups, that is,

The term "conjugated radical / conjugated group" means a group mainly containing sp ² -hybrid (or possibly sp-hybrid) carbon atoms, which can also be replaced by corresponding heteroatoms. In the simplest case, this means alternating double and single bonds. In this connection, "mainly" means that the natural (non-random) defects that cause the conjugate interruption do not devalue the term "conjugate". Furthermore, if, for example, an arylamine unit or certain heterocycles (ie, conjugated via N, O, P, or S atoms) are positioned in the group, the term "conjugated" is also used herein in this application.

The term "polymerizable group" (P ^1-3 ) means that it is suitable for use in a polymerization reaction (for example, radical or ionic chain polymerization, addition polymerization or polycondensation) or a polymer-like reaction (for example, addition or condensation to a main polymerization On the chain). Particularly preferred are groups used for chain polymerization, especially those containing a C = C double bond or -C≡C-reference bond, and groups suitable for ring-opening polymerization, such as oxetanyl or Epoxy.

Preferred groups P ^{1-3 are} selected from the group consisting of: CH ₂ = CW ¹ -CO-O-, CH ₂ = CW ¹ -CO-, , CH ₂ = CW ^2- (O) _k3- , CW ¹ = CH-CO- (O) _k3- , CW ¹ = CH- CO-NH-, CH ₂ = CW ¹ -CO-NH-, CH _3- CH = CH-O-, (CH ₂ = CH) ₂ CH-OCO-, (CH ₂ = CH-CH ₂ ) ₂ CH-OCO-, (CH ₂ = CH) ₂ CH-O-, (CH ₂ = CH-CH ₂ ) ₂ N-, (CH ₂ = CH-CH ₂ ) ₂ N-CO-, HO-CW ² W ^3- , HS-CW ² W ^3- , HW ² N-, HO-CW ² W ³ -NH-, CH ₂ = CW ¹ -CO-NH-, CH ₂ = CH- (COO) _k1 -Phe- (O) _k2- , CH ₂ = CH- (CO) _k1 -Phe- (O) _k2 -, Phe-CH = CH-, HOOC-, OCN-, and W ⁴ W ⁵ W ⁶ Si-, where W ¹ represents H, F, Cl, CN, CF ₃ , phenyl, or one having 1 to 5 C atoms alkyl, especially H, F, Cl or CH _3, W ² and W ³ are each independently of one another, denote H or alkyl having 1 to 5 C atoms, in particular H, methyl, ethyl or n-propyl, W ⁴ , W ⁵ and W ⁶ each independently represent Cl, an oxaalkyl group or an oxacarbonylalkyl group having 1 to 5 C atoms, and W ⁷ and W ⁸ each independently represent H, Cl, or 1 to An alkyl group of 5 C atoms, Phe represents 1,4-phenylene, optionally substituted with one or more groups L as defined above except P-Sp-, k ₁ , k ₂ and k ₃ each independently represents 0 or 1, k _{3 is a} better table Show 1 and k ₄ represents an integer from 1 to 10.

The particularly preferred group P ^{1-3 is} selected from the group consisting of: CH ₂ = CW ¹ -CO-O-, CH ₂ = CW ¹ -CO-, , CH ₂ = CW ² -O-, CH ₂ = CW ^2- , CW ¹ = CH-CO- (O) _k3- , CW ¹ = CH-CO-NH-, CH ₂ = CW ¹ -CO-NH- (CH ₂ = CH) ₂ CH-OCO-, (CH ₂ = CH-CH ₂ ) ₂ CH-OCO-, (CH ₂ = CH) ₂ CH-O-, (CH ₂ = CH-CH ₂ ) ₂ N-, (CH ₂ = CH-CH ₂ ) ₂ N-CO-, CH ₂ = CW ¹ -CO-NH-, CH ₂ = CH- (COO) _k1 -Phe- (O) _k2- , CH ₂ = CH- (CO) _k1 -Phe- (O) _k2- , Phe-CH = CH- and W ⁴ W ⁵ W ⁶ Si-, where W ¹ represents H, F, Cl, CN, CF ₃ , phenyl or Alkyl groups of 1 to 5 C atoms, especially H, F, Cl or CH ₃ , W ² and W ³ each independently represent H or an alkyl group of 1 to 5 C atoms, especially H, methyl, ethyl Or n-propyl, W ⁴ , W ⁵ and W ⁶ each independently represent Cl, oxaalkyl or oxacarbonylalkyl having 1 to 5 C atoms, W ⁷ and W ⁸ each independently H, Cl or an alkyl group having 1 to 5 C atoms, Phe represents 1,4-phenylene, k ₁ , k ₂ and k ₃ each independently represent 0 or 1, k ₃ preferably represents 1 and k ₄ represents an integer from 1 to 10.

The extremely preferred group P ^{1-3 is} selected from the group consisting of: CH ₂ = CW ¹ -CO-O-, especially CH ₂ = CH-CO-O-, CH ₂ = C (CH ₃ ) -CO -O- and CH ₂ = CF-CO-O-, and CH ₂ = CH-O-, (CH ₂ = CH) ₂ CH-O-CO-, (CH ₂ = CH) ₂ CH-O-,

Other extremely preferred groups P ^{1-3 are} selected from the group consisting of vinyl, vinyloxy, acrylate, methacrylate, fluoroacrylate, chloroacrylate, and oxo Butyl and epoxy, particularly preferably acrylate, methacrylate or oxetanyl.

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

In detail, if the spacer group Sp ^{1-3 is} different from a single bond, it is preferably of the formula Sp "-X", so that the respective groups P ⁱ -Sp ^i- (such as P ¹ -Sp ^1- ) conform to The formula P-Sp "-X"-, where Sp "and X" have the meanings given below.

If the spacer group Sp ^{4 is} different from a single bond, it is preferably of formula X "-Sp" such that the respective groups -A ² -Sp ⁴ -conform to the formula -A ² -X "-Sp"-, where Sp "And X" have the meanings given below.

"Sp" represents an alkylene group having 1 to 20, preferably 1 to 12 C atoms, which is optionally mono- or poly-substituted by F, Cl, Br, I or CN, and in addition, one or more of them are not Adjacent CH ₂ groups can be made independent of each other via -O-, -S-, -NH-, -N (R ⁰ )-, -Si (R ⁰⁰ R ⁰⁰⁰ )-, -CO-, -CO-O-, -O-CO-, -O-CO-O-, -S-CO-, -CO-S-, -N (R ⁰⁰ ) -CO -O-, -O-CO-N (R ⁰⁰ )-, -N (R ⁰⁰ ) -CO-N (R ⁰⁰ )-, -CH = CH- or -C≡C- substitution, X "means -O -, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O-, -CO-N (R ⁰⁰ )-, -N (R ⁰⁰ ) -CO-, -N (R ⁰⁰ ) -CO-N (R ⁰⁰ )-, -OCH _2- , -CH ₂ O-, -SCH _2- , -CH ₂ S-, -CF ₂ O-, -OCF ₂ -,- CF ₂ S-, -SCF _2- , -CF ₂ CH _2- , -CH ₂ CF _2- , -CF ₂ CF _2- , -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 bond, R ⁰⁰ and R ⁰⁰⁰ are each other Independently represents H or an alkyl group having 1 to 12 C atoms, and Y ² and Y ³ each independently represent H, F, Cl, or CN.

"X" is preferably -O-, -S-, -CO-, -COO-, -OCO-, -O-COO-, -CO-NR ^0- , -NR ⁰ -CO-, -NR ⁰ -CO -NR ⁰ -or single key.

Typical spacer groups -Sp "-X"-are, for example,-(CH ₂ ) _p1 -,-(CH ₂ CH ₂ O) _q1 -CH ₂ CH _2- , -CH ₂ CH ₂ -S-CH ₂ CH ₂ -, -CH ₂ CH ₂ -NH-CH ₂ CH ₂ -or-(SiR ⁰⁰ R ⁰⁰⁰ -O) _p1- , where p1 is an integer from 1 to 12, q1 is an integer from 1 to 3, and R ⁰⁰ and R ⁰⁰⁰ has the meaning indicated above.

Especially preferred group -Sp "-X" -is-(CH ₂ ) _p1 -,-(CH ₂ ) _p1 -O-,-(CH ₂ ) _p1 -O-CO-,-(CH ₂ ) _p1 -O -CO-O-, wherein p1 and q1 have the meanings indicated above.

You Jiaji group -X "-Sp" - is _{- (CH 2) p1 -,} - O- (CH 2) p1 -, - CO-O- (CH 2) p1 -, - O-CO-O- ( CH ₂ ) _p1- , where p1 and q1 have the meanings indicated above.

In each case, particularly preferred groups Sp "are, for example, straight-chain ethylene, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, Undecyl, Dodecyl, Octadecyl, Ethyloxyalkylene, Methyleneoxybutylene, Ethylthioalkylene, Ethylene-N-methylimine Ethylene, 1-methylalkylene, vinylidene, propenyl, and butenyl.

According to a preferred embodiment of the invention, the compound of formula I is dissolved or suspended in the other components of the LC medium.

According to the present invention, the LC medium is a liquid crystal composition suitable for liquid crystal drip (ODF) technology.

To control the orientation of the LC medium, the surface of a supporting substrate such as glass is usually coated with a polymer. The polymer may be any one having at least one polar group selected from a carboxyl group, a hydroxyl group, and an amine group in the molecular chain of the polymer. Preferably, the polymer is a polyfluorene-type polymer. The solution of polyimide polymer can be called polyimide-type varnish.

When a polyimide-type varnish is applied to a support substrate in order to treat the support surface, the solvent is then preferably removed at a temperature between 50 ° C and 250 ° C, and a polymer film is thereby formed. The polyimide-type polymer film thus formed on the support substrate may be subjected to a physical or mechanical surface treatment such as rubbing. For the rubbing treatment, any method can be adopted. Examples of rubbing treatments are described and known to those skilled in the art. Wrap a rubbing cloth of cotton, cotton, polyamide or the like on a metal roller, and rotate and move the roller while contacting the supporting substrate or polymer film; or only move the supporting substrate without rotating The position of the roller.

Polyimide varnish capable of forming a polymer film on a supporting substrate is a polymer component (such as polyamic acid, polyamidamine, polyimide, soluble polyimide or polyimide) Amine) varnish composition dissolved in a solvent. The varnish composition is applied to a support support and then dried to form a polymer film thereon. The polymer component constituting the polymer film may be a copolymer such as a random copolymer or a block copolymer, and may be a mixture of different types of polymer components.

Polyimide polymers which are preferably used to form a polymer film are those having a hydrazine bond, a fluorenimine bond, a carboxyl group produced by amidation, a fluorinated group of a carboxyl group, or an esterification of a carboxyl group Group of polymers. Preferred examples of this type of polymer are polyamidic acid, polyamidoamine, and polyamidate. However, in the present invention, in addition to these preferred polymers, a soluble polyimide obtained by dehydration of polyamidic acid and polyamido-imine is also applicable. Among them, polyamines and polyamidoamines are more preferred; and polyamidates are most preferred.

The tetracarboxylic dianhydrides used to obtain the polyamines, polyamidoamines, polyamidates, soluble polyamidoimines or polyamidoimines may be aromatic compounds (Including heterocyclic aromatic compounds), wherein the dicarboxylic anhydride is directly bonded to the aromatic ring; or any of the groups of aliphatic compounds (including heterocyclic aliphatic compounds), wherein the dicarboxylic acid The anhydride is not directly bonded to the aromatic ring.

In a preferred embodiment of the present invention, the transparent substrate is a polymer substrate, preferably a polyimide (RI) substrate, for example, by using JSR-2347 (JSR) and JSR-2503 (JSR). Polyimide (PI) substrate.

Generally, for example, by using a SE-4811 (Nissan Chemical) produced polyimide film, which is a commercial polyimide resin and is used to produce the VA layer in the LCD industry, has a surface energy of about 31 mJ / m ² .

The surface energy of the alignment layer can be determined by methods known to those skilled in the art, such as by contact angle measurement using a Kruss DSA-100 instrument.

Although the correlation between surface energy and molecular alignment has not been clearly clarified, it has been accepted that surfaces with low surface energy will also support the VA of LC molecules.

According to the present invention, the compound of formula I reduces the surface tension (or interfacial tension) between the liquid crystal composition and the alignment layer, and reduces the ductility of the liquid crystal composition provided on the alignment layer by the liquid crystal dripping method, thereby improving the reactive monomer The volume is uniformly distributed in the LC dielectric layer adjacent to the surface of the alignment layer, and thus the occurrence of dripping dead spots is avoided or reduced.

And theory (see Lee et al. In Photonics Letters of Poland 2010, 3, (1), pages 8-10 and Schwartz et al. In ACS Appl. Mater. Interfaces 2011, 3, (11), pages 4374-4380 ) Good agreement, but not limited or bound by theory, the inventor believes that the compound of formula I can chemically or physically interact with the surface of the alignment layer, and at the same time form a self-alignment layer on the surface of the alignment layer, wherein the surface energy of the alignment layer reduce.

For the production of PSA displays, polymerizable compounds are polymerized or crosslinked by in situ polymerization in an LC medium between substrates of the LC display under an applied voltage (if a compound contains two or more polymerizable groups). Polymerization can be performed in one step. It is also possible to first polymerize under an applied voltage in the first step to produce a pretilt angle, and then polymerize or crosslink the unreacted compounds in the first step without applying a voltage in the second polymerization step ("final Curing ").

Suitable and preferred polymerization methods are, for example, thermal polymerization or photopolymerization, preferably photopolymerization, especially UV photopolymerization. Optionally, one or more initiators can also be added here. Suitable conditions for polymerization and suitable types and amounts of initiators are known to those skilled in the art and are described in the literature. Suitable for free radical polymerization are, for example, commercially available photoinitiators Irgacure651®, Irgacure184®, Irgacure907®, Irgacure369® or Darocure1173® (Ciba AG). If an initiator is used, the proportion is preferably 0.001% to 5% by weight, and particularly preferably 0.001% to 1% by weight.

The polymerizable compound according to the present invention is also suitable for polymerization without an initiator, which is accompanied by a large number of advantages, such as lower material costs and, in particular, less contamination of the LC medium by possible residual amounts of the initiator or its degradation products. Therefore, polymerization can also be performed without the addition of an initiator. In a preferred embodiment, the LC medium therefore does not contain a polymerization initiator.

The LC medium may also contain one or more stabilizers in order to prevent unwanted spontaneous polymerization of RM, for example 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 are commercially available stabilizers such as those from the Irganox® series (Ciba AG), such as Irganox® 1076. If a stabilizer is used, the proportion is preferably from 10 ppm to 500,000 ppm, particularly preferably from 50 ppm to 50,000 ppm, based on the total amount of RM or polymerizable component A).

Especially preferred are LC media containing one, two or three polymerizable mesogen compounds.

Especially preferred are LC media containing one, two or three compounds of formula I.

Especially preferred is an LC medium containing one, two, three or more non-polymerizable mesogen compounds.

The proportion of polymerizable compounds in the LC medium according to the present invention is preferably> 0 to <5%, particularly preferably> 0 to <1%, and particularly preferably 0.01% to 0.5%.

The proportion of the non-polymerizable mesogen compound in the LC medium according to the present invention is preferably 95% to <100%, particularly preferably 99% to <100%.

The LC medium according to the present invention for a PSA display preferably contains> 0 to <20% by weight, particularly preferably> 0 to <5% by weight, and very preferably 0.01 to 0.5% by weight of a compound of formula I.

In addition, an LC medium having a nematic liquid crystal phase is preferred.

Furthermore, an LC medium according to the present invention is preferred, wherein the compound is completely selected from the group consisting of non-palladium compounds.

Preferably, as described above and below, the LC medium according to the present invention consists essentially of one or more polymerizable mesogen compounds, one or more non-polymerizable mesogen compounds and one or more compounds of formula I.

However, the LC medium may additionally include one or more other components or additives, and is preferably selected from the list including (but not limited to) the following: comonomers, palm dopants, polymerization initiators, inhibitors, stabilizers, Surfactants, wetting agents, lubricants, dispersants, hydrophobic agents, adhesives, flow improvers, defoamers, deaerators, diluents, reactive diluents, additives, colorants, dyes, pigments and Nano particles.

Suitable and preferred compounds of formula I are selected, for example, from the formula:

Wherein R ^a , R ^b , R ^c , ^Rd and n have one of the meanings given according to formula I.

In addition, preferred are compounds of formula I selected from, for example, the following formula:

Wherein R ^a , R ^c and n have one of the meanings given according to formula I.

Preferred compounds of the formulae A1 to C4 are selected from the group wherein R ^a represents hydrogen, methyl, ethyl, methoxy, ethoxy, phenyl, benzyl, methylphenyl or methoxyphenyl and R ^c and n A compound having one of the meanings given according to formula I.

More preferably the compounds of formulae A1 to C4 are selected from the group wherein R ^a represents hydrogen, methyl, ethyl, methoxy, ethoxy, phenyl, benzyl, methylphenyl or methoxyphenyl; R ^{c is} independently R ^a represents methyl, ethyl, methoxy, ethoxy, phenyl, benzyl, methylphenyl or methoxyphenyl; and n has one of the meanings given according to formula I者 的 Compound.

Examples of particularly preferred compounds are given below:

Where n is 1, 2, 3, or 4.

Preferably one or more polymerizable compounds containing one polymerizable group (single-reactive) and / or one or more polymerizable compounds containing two or more, preferably two, polymerizable groups (dual-reactive or Multi-reactive) LC media for polymerizable compounds.

Polymerizable compounds can be polymerized individually, but it is also possible to polymerize two or two A mixture of more than one polymerizable compound, or a mixture comprising one or more polymerizable compounds and one or more other polymerizable compounds ("comonomers"), which are preferably mesogens or liquid crystals. Where these mixtures are polymerized, a copolymer is formed.

Suitable and preferred polymerizable mesogen compounds (especially for PSA-VA displays) are selected, for example, from the formula:

The individual groups have the following meanings: P ¹ , P ² and P ³ each independently represent a polymerizable group, preferably having one of the meanings indicated above and below for P, particularly preferably an acrylate group , Methacrylate, fluoroacrylate, oxetanyl, vinyl, vinyloxy or epoxy, and Sp ¹ , Sp ² and Sp ³ each independently represent a single bond or a spacer group Preferably has one of the meanings indicated above and below for Sp, and particularly preferably represents-(CH ₂ ) _p1 -,-(CH ₂ ) _p1 -O-,-(CH ₂ ) _p1 -CO- O- or-(CH ₂ ) _p1 -O-CO-O-, where p1 is an integer from 1 to 12, and wherein the connection to the adjacent ring in the last-mentioned group proceeds via an O atom, and further, where the group ^{P 1 -Sp 1 -, P 1} -Sp 2 - and P ³ -Sp ³ - or may represent one of R ^aa, group with the proviso that the presence of ^{P 1 -Sp 1 -, P 2} - Sp ² and P ³ -Sp ³ - in at least one of the not represented R ^aa, R ^aa represents H, F, Cl, CN or a linear or branched alkyl group having 1 to 25 C atoms, further wherein a or more non-adjacent CH ₂ groups may be such that an O atom and / or the original S The embodiment is not connected directly to one another independently of one another are each substituted with ^{C (R 0) = C (} R 00) -, - C≡C-, C (R 0) = C (R 00) -, - C≡C -, - N (R ⁰ )-, -O-, -S-, -CO-, -CO-O-, O-, -O-CO-, -O-CO-O- substitution, and in addition, one or more of them H atoms can be passed through F; Cl; CN; or P ¹ -Sp ^1- ; particularly preferably a straight or branched chain of 1 to 12 C atoms, optionally monofluorinated or polyfluorinated alkyl, alkoxy , Alkenyl, alkynyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy, or alkoxycarbonyloxy (where alkenyl and alkynyl have at least two C atoms and branched chain groups have at least three C atoms) substitution, each occurrence of R ⁰ , R ⁰⁰ independently and identically or differently represents H or an alkyl group having 1 to 12 C atoms, and R ^y and R ^z each independently represent H , F, CH ₃ or CF ₃ , X ¹ , X ² and X ³ each independently represent -CO-O-, -O-CO- or a single bond, and Z ¹ represents -O-, -CO-, -C (R ^y R ^z )-or -CF ₂ CF _2- , Z ² and Z ³ each independently represent -CO-O-, -O-CO-, -CH ₂ O-, -OCH _2- , -CF ₂ O-, -OCF ₂ -or-(CH ₂ ) _n- , where n is 2, 3 or 4, and L is Currently, identically or differently represents F, Cl, CN or optionally a linear or branched chain having 1 to 12 C atoms. Mono- or polyfluorinated alkyl, alkoxy, alkenyl, alkynyl, alkane Carbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy, preferably F, L 'and L "each independently represent H, F or Cl, and r represents 0, 1, 2, 3 Or 4, s means 0, 1, 2 or 3, t means 0, 1 or 2, and x means 0 or 1.

Especially preferred are compounds of the formulae M1 to M28.

In compounds of formulas M1 to M42 Preferably Wherein L in each occurrence has the same or different one of the meanings given above or below, and is preferably F, Cl, CN, NO ₂ , CH ₃ , C ₂ H ₅ , C (CH ₃ ) ₃ , CH (CH ₃ ) ₂ , CH ₂ CH (CH ₃ ) C ₂ H ₅ , OCH ₃ , OC ₂ H ₅ , COCH ₃ , COC ₂ H ₅ , COOCH ₃ , COOC ₂ H ₅ , CF ₃ , OCF _3. OCHF ₂ , OC ₂ F ₅ or P-Sp-, excellent F, Cl, CN, CH ₃ , C ₂ H ₅ , OCH ₃ , COCH ₃ , OCF ₃ or P-Sp-, more preferably F, Cl , CH ₃ , OCH ₃ , COCH ₃ or OCF ₃ , especially F or CH ₃ .

In addition to the polymerizable compounds described above, the LC medium according to the present invention for LC displays contains a mixture of non-polymerizable mesogens (also referred to as "host mixtures"), which are non-polymerizable mesogens. It contains one or more, preferably two or more non-polymerizable mesogen compounds.

In principle, any LC mixture suitable for conventional VA and OCB displays is suitable as the host mixture. Suitable LC mixtures are known to those skilled in the art and are described in the literature, for example mixtures in VA displays in EP 1 378 557 A1 and mixtures of OCB displays in EP 1 306 418 A1 and DE 102 24 046 A1 .

Suitable and preferred non-polymerizable mesogens are their non-polymerizable mesogens which exhibit negative dielectric anisotropy. These compounds are particularly suitable for PSA-VA displays. A particularly preferred embodiment is one of the following: a) an LC medium comprising one or more compounds of the formula CY and / or PY:

Where a is 1 or 2, and b is 0 or 1, Express or

R ¹ and R ² each independently represent an alkyl group having 1 to 12 C atoms. In addition, one or two non-adjacent CH ₂ groups may pass through the -O-, -CO-, -OCO- or -COO- substitution, preferably an alkyl or alkoxy group having 1 to 6 C atoms, Z ^x and Z ^y each independently represent -CH ₂ CH _2- , -CH = CH-, -CF ₂ O-, -OCF _2- , -CH ₂ O-, -OCH _2- , -CO-O-, -O-CO-, -C ₂ F _4- , -CF = CF-, -CH = CH-CH ₂ O- or a single bond, preferably a single bond, L ¹ , L ² , L ³ , L ⁴ each independently represent F, Cl, OCF ₃ , CF ₃ , CH ₃ , CH ₂ F, CHF ₂ .

Preferably, both L ¹ and L ² represent F, or one of L ¹ and L ² represents F and the other represents Cl, or both L ³ and L ⁴ represent F, or L ³ and One of L ⁴ represents F and the other represents Cl.

The compound of formula CY is preferably selected from the group consisting of:

Wherein a represents 1 or 2, alkyl and alkyl * each independently represent a linear alkyl group having 1 to 6 C atoms, and (O) represents an oxygen atom or a single bond.

The compound of formula PY is preferably selected from the group consisting of:

Here, the alkyl group and the alkyl group * each independently represent a linear alkyl group having 1 to 6 C atoms, and (O) represents an oxygen atom or a single bond.

b) LC media additionally containing one or more compounds of the formula:

The individual groups have the following meanings: Express Express or R ³ and R ⁴ each independently represent an alkyl group having 1 to 12 C atoms. In addition, one or two non-adjacent CH ₂ groups may pass through the -O-, -CO-, -O-CO- or -CO-O- substitution, Z ^y represents -CH ₂ CH _2- , -CH = CH-, -CF ₂ O-, -OCF _2- , -CH ₂ O-, -OCH _2- , -CO-O-, -O-CO-, -C ₂ F _4- , -CF = CF-, -CH = CH-CH ₂ O- or a single bond, preferably a single bond.

The compound of formula ZK is preferably selected from the group consisting of:

Wherein alkyl and alkyl * each independently represent a linear alkyl group having 1-6 C atoms, and c) an LC medium additionally containing one or more compounds of the formula:

Where each individual group has the same or different meaning at each occurrence: R ⁵ and R ⁶ each independently of one of the meanings indicated above for R ¹ , Express or Express or , And e represents 1 or 2.

The compound of formula DK is preferably selected from the group consisting of:

Where alkyl and alkyl * each independently represent a linear alkyl group having 1-6 C atoms, d) an LC medium additionally containing one or more compounds of the formula:

The individual groups have the following meanings: Express

f represents 0 or 1, R ¹ and R ² each independently represent an alkyl group having 1 to 12 C atoms. In addition, one or two non-adjacent CH ₂ groups can make O atoms not directly connected to each other. The method is replaced by -O-, -CO-, -OCO-, or -COO-, and Z ^x and Z ^y each independently represent -CH ₂ CH _2- , -CH = CH-, -CF ₂ O-, -OCF _2- , -CH ₂ O-, -OCH _2- , -CO-O-, -O-CO-, -C ₂ F _4- , -CF = CF-, -CH = CH-CH ₂ O- or single The bond is preferably a single bond, and L ¹ and L ² each independently represent F, Cl, OCF ₃ , CF ₃ , CH ₃ , CH ₂ F, CHF ₂ .

Preferably, both L ¹ and L ² represent F, or one of the groups L ¹ and L ² represents F and the other represents Cl.

The compound of formula LY is preferably selected from the group consisting of:

Wherein R ¹ has the meaning indicated above, alkyl represents a straight-chain alkyl group having 1-6 C atoms, (O) represents an oxygen atom or a single bond, and v represents an integer of 1 to 6. R ¹ preferably represents a straight-chain alkyl group having 1 to 6 C, especially CH ₃ , C ₂ H ₅ , nC ₃ H ₇ , nC ₄ H ₉ , nC ₅ H ₁₁ .

e) an LC medium additionally comprising one or more compounds selected from the group consisting of:

Wherein R ⁵ has ^one of the meanings indicated above for R ¹ , alkyl represents C _1-6 alkyl, d represents 0 or 1, and z and m each independently represent an integer of 1 to 6. Among these compounds, R ^{5 is} particularly preferably C _1-6 alkyl or C _1-6 alkoxy, and d is preferably 1. The content of the LC medium according to the present invention is preferably 5% by weight of one or more compounds of the formula mentioned above.

f) an LC medium additionally comprising one or more biphenyl compounds selected from the group consisting of:

Wherein the alkyl group and the alkyl group * each independently represent a linear alkyl group having 1 to 6 C atoms, and the proportion of the biphenyl of formula B1 in the LC mixture is preferably at least 3% by weight, especially 5 wt%.

g) LC media additionally containing one or more terphenyl compounds:

Wherein R ⁵ and R ⁶ each independently have ^one of the meanings indicated above for R ¹ , and

Represented independently of each other

Wherein L ⁵ represents F or Cl, preferably F, and L ⁶ represents F, Cl, OCF ₃ , CF ₃ , CH ₃ , CH ₂ F, or CHF ₂ , and F is preferred.

The compound of formula T is preferably selected from the group consisting of:

Wherein R represents a linear alkyl or alkoxy group having 1 to 7 C atoms, (O) represents an oxygen atom or a single bond, and m represents an integer of 1 to 6.

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

The LC medium according to the present invention preferably contains bitriphenyl of formula T and its preferred sub-formula in an amount of 0.5% to 30% by weight, especially 1% to 20% by weight.

Especially preferred are compounds of formulae T1, T2, T3 and T21. Among these compounds, R preferably represents an alkyl group each having 1 to 5 C atoms, and furthermore an alkoxy group.

If the Δn value of the mixture 0.1, bitriphenyl is preferably used in the mixture according to the invention. A preferred mixture comprises 2 to 20% by weight of one or more terphenyl compounds of formula T, preferably selected from the group of compounds T1 to T21.

h) an LC medium additionally comprising one or more compounds selected from the group consisting of:

Wherein R ¹ and R ² have the meanings indicated above, and preferably each independently represents a straight-chain alkyl group having 1 to 6 C atoms.

Preferred media include one or more compounds selected from the group consisting of formulae O1, O3 and O4.

i) LC media additionally containing one or more compounds of the formula:

among them Express R ⁹ represents H, CH ₃ , C ₂ H ₅ or nC ₃ H ₇ , (F) represents an optional fluorine substituent, and q represents 1, 2 or 3, and R ⁷ has the meaning indicated for R ¹ One of them is preferably> 3% by weight, especially 5% by weight and very particularly preferably 5% to 30% by weight.

Particularly preferred compounds of formula FI are selected from the group consisting of:

Among them, R ⁷ preferably represents a linear alkyl group, and R ⁹ represents CH ₃ , C ₂ H ₅ or nC ₃ H ₇ . Especially preferred are compounds of formulae FI1, FI2 and FI3.

j) an LC medium additionally comprising one or more compounds selected from the group consisting of:

Wherein R ⁸ has the meaning indicated for R ¹ , and the alkyl group means a straight-chain alkyl group having 1 to 6 C atoms.

k) LC media additionally comprising one or more compounds containing tetrahydronaphthyl or naphthyl units, such compounds being selected, for example, from the group consisting of:

Wherein R ¹⁰ and R ¹¹ each independently have ^one of the meanings indicated for R ¹ , and preferably represent a linear alkyl group or alkoxy group having 1 to 6 C atoms, and Z ¹ and Z ² each -C ₂ H _4- , -CH = CH-,-(CH ₂ ) ₄ -,-(CH ₂ ) ₃ O-, -O (CH ₂ ) _3- , -CH = CH-CH ₂ CH _2- , -CH ₂ CH ₂ CH = CH-, -CH ₂ O-, -OCH _2- , -CO-O-, -O-CO-, -C ₂ F _4- , -CF = CF-, -CF = CH-, -CH = CF-, -CH ₂ -or a single bond.

l) additionally contains one or more difluorodibenzo Alkane and / or LC medium:

Wherein R ¹¹ and R ¹² each have the meanings indicated above, independently of each other, ring M is trans-1,4-cyclohexyl or 1,4-phenylene, and Z ^m -C ₂ H ₄ -,- CH ₂ O-, -OCH _2- , -CO-O- or -O-CO-, c is 0 or 1, preferably 3 to 20% by weight, especially 3 to 15% by weight .

Particularly preferred compounds of the formulae BC, CR and RC are selected from the group consisting of:

The alkyl group and the alkyl group * each independently represent a linear alkyl group having 1 to 6 C atoms, (O) represents an oxygen atom or a single bond, and c is 1 or 2.

Very particularly preferred is a mixture comprising one, two or three compounds of formula BC-2.

m) LC media additionally containing one or more phenanthrene fluoride and / or dibenzofuran of the formula:

Wherein R ¹¹ and R ¹² each independently have the meanings indicated above, b represents 0 or 1, L represents F, and r represents 1, 2 or 3.

Particularly preferred compounds of the formulas PH and BF are selected from the group consisting of:

Wherein R and R 'each independently represent a straight-chain alkyl group or alkoxy group having 1 to 7 C atoms.

n) LC media additionally containing one or more monocyclic compounds of the formula:

Wherein R ¹ and R ² each independently represent an alkyl group having 1 to 12 C atoms, and in addition, one or two non-adjacent CH ₂ groups can pass O atoms in a manner such that O atoms are not directly connected to each other via -O- , -CH = CH-, -CO-, -OCO- or -COO- substitution, preferably an alkyl or alkoxy group having 1 to 6 C atoms, L ¹ and L ² each independently represent F, Cl , OCF ₃ , CF ₃ , CH ₃ , CH ₂ F, CHF ₂ .

Preferably, both L ¹ and L ² represent F, or one of L ¹ and L ² represents F and the other represents Cl. The compound of formula Y is preferably selected from the group consisting of the following subformulas:

Here, the alkyl group and the alkyl group * each independently represent a linear alkyl group having 1-6 C atoms, and the alkoxy group represents a linear alkoxy group having 1-6 C atoms.

Particularly preferred compounds of formula Y are selected from the group consisting of:

Among them, the alkoxy group preferably represents a straight-chain alkoxy group having 3, 4 or 5 C atoms.

o) other than the polymerizable compounds according to the present invention, the LC medium does not comprise a compound containing blocked alkylene (-CH = CH ₂₎ of the.

p) LC medium comprising 1 to 5, preferably 1, 2 or 3 polymerizable compounds, preferably selected from polymerizable compounds according to the invention.

q) The proportion of the polymerizable compound in the mixture is generally 0.05% to 5%, preferably 0.1% to 1% of the LC medium.

r) LC media containing 1 to 5, preferably 1, 2 or 3 compounds of formula I, preferably selected from compounds of formulas A1 to C4.

s) The proportion of the compound of formula I in the mixture is generally from 0.05% to 5%, preferably from 0.1% to 1% of the LC medium.

t) LC media containing 1 to 8, preferably 1 to 5, compounds of formula CY, especially compounds of formula CY1, CY2, CY15 and / or CY16. The proportion of these compounds in the mixture is generally preferably 5% to 60%, particularly preferably 10% to 40%. In each case, the content of these individual compounds is preferably 2% to 20%.

u) LC media containing 1 to 8, preferably 1 to 5, compounds of formula PY, especially compounds of formula PY9 and / or PY10. The proportion of these compounds in the mixture is generally preferably 5% to 60%, particularly preferably 10% to 35%. In each case, the content of these individual compounds is preferably 2% to 20%.

v) LC media containing 1 to 10, preferably 1 to 8 compounds of formula ZK, especially compounds of formula ZK1, ZK2, ZK4 and / or ZK5. The proportion of these compounds in the mixture is generally from 3% to 50%, particularly preferably from 5% to 45%. In each case, the content of these individual compounds is preferably 2% to 20%.

w) LC media in which the proportion of compounds of formula CY, PY and ZK in the mixture is generally greater than 70%, preferably greater than 80%.

x) LC media containing one or more, preferably 1, 2 or 3 compounds of formula T2. The content of these compounds in the mixture is generally 1% to 20%.

The combination of the compounds of the preferred embodiments mentioned above and the polymeric compounds described above produces a low threshold voltage, a low rotational viscosity, and an excellent low temperature stability in the LC medium according to the invention, while producing a constant High-definition clear points and high HR values, and allow for particularly low pre-tilt angles to be quickly established in PSA displays. In particular, compared to the media from the prior art, LC media exhibit significantly shorter response times, especially grayscale response times, in PSA displays.

The nematic phase range of the liquid crystal mixture is preferably at least 80K, particularly preferably at least 100K, and the rotational viscosity at 20 ° C is not greater than 250 mPa. s, preferably not more than 200mPa. s.

In the VA type display according to the present invention, the molecules in the LC dielectric layer in the off state are aligned perpendicular to the electrode surface (vertically) or have an oblique vertical alignment. After applying a voltage to the electrode, a realignment of the LC molecules occurs, where the longitudinal molecular axis is parallel to the electrode surface.

According to the first preferred embodiment, the negative dielectric anisotropy Δε of the LC medium according to the present invention (particularly for PSA-VA type displays) based on a compound having negative dielectric anisotropy is preferably at 20 ° C and 1 kHz It is -0.5 to -10, especially -2.5 to -7.5.

The birefringence Δn in the LC medium according to the present invention for a PSA-VA type display is preferably less than 0.16, particularly preferably 0.06 to 0.14, and even more preferably 0.07 to 0.12.

In the OCB type display according to the present invention, the molecules in the LC dielectric layer have a "bent" alignment. After the voltage is applied, a realignment of the LC molecules occurs, where the longitudinal molecular axis is perpendicular to the electrode surface.

The LC medium according to the present invention for a PSA-OCB type display is preferably their LC medium based on a compound having positive dielectric anisotropy according to the second preferred embodiment, and the positive dielectric anisotropy Δε is 20 It is preferably +4 to +17 at ° C and 1 kHz.

The birefringence Δn in the LC medium according to the present invention for a PSA-OCB type display is preferably 0.14 to 0.22, particularly preferably 0.16 to 0.22.

The LC medium according to the present invention may also contain other additives known to those skilled in the art and described in the literature, for example, polymerization initiators, inhibitors, stabilizers (as given, for example, in Table F), other surface actives Substance or palmar dopant.

In a preferred embodiment, the LC medium contains one or more palmitic dopants at a preferred concentration of 0.01% to 1%, and preferably 0.05% to 0.5%. The palmitic dopant is preferably selected from the group consisting of compounds from Table B below, and is preferably selected 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.

In another preferred embodiment, the LC medium contains one or more racemic dopants, which are preferably selected from the palmitic dopants mentioned in the previous paragraph.

In addition, it is possible to add, for example, 0 to 15% by weight of a multicolor dye to the LC medium, in addition to nano particles, a conductive salt (preferably 4-hexyloxybenzoate ethyldimethyldodecylammonium, tetraphenyl Tetrabutylammonium borate or crown ether complex salt) (see, eg, Haller et al., Mol. Cryst. Liq. Cryst. 24 , 249-258 (1973)) for improving conductivity; or adding to modify the dielectric properties Anisotropic, viscous and / or nematically aligned substance. Substances of this type 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.

LC media which can be used according to the invention are in a manner known per se, for example by mixing one or more of the compounds mentioned above with one or more polymerizable compounds and one or more compounds of the formula I as defined above , And optionally with other liquid crystal compounds and / or additives. In general, the required amount of the component used in a smaller amount is favorably dissolved in the component constituting the main component at a high temperature. It is also possible to mix a solution of the components in an organic solvent, such as acetone, chloroform or methanol, and to remove the solvent again after thorough mixing, for example by distillation. Furthermore, the present invention relates to a method for preparing an LC medium according to the present invention.

It is self-evident to those skilled in the art that the LC medium according to the present invention may also include compounds in which, for example, H, N, O, Cl, F have been replaced by corresponding isotopes.

The invention is described above and below with specific reference to the preferred embodiments. It should be understood that various changes and modifications can be made therein without departing from the spirit and scope of the invention.

Many of the compounds mentioned above and below or mixtures thereof are commercially available. Organic compounds are known or can be prepared by methods known per se, as described in the literature (for example in standard works such as Houben-Weyl, Methoden der Organischen Chemie [Methods of Organic Chemistry], Georg-Thieme-Verlag, Stuttgart ), Specifically it is prepared under known reaction conditions suitable for such reactions. Variations of the methods known per se but not mentioned herein can also be used herein.

Unless the context clearly indicates otherwise, as used herein, terms used herein The plural should be considered to include the singular, and vice versa.

Throughout this application, unless explicitly stated otherwise, the parameter range includes all rational and integer values, including the specified limit of the parameter range and its error limit. Combinations of the illustrated upper and lower limits of the respective ranges with additional preferred ranges result in other preferred embodiments.

Throughout the description of the embodiments of this specification and the scope of patent applications, the word "including (comprise) and “contain” and variations of these terms, such as “comprising” and “comprises” means “including (but not limited to)” and are not intended (and are not ) Exclude other components. On the other hand, the word "comprising" also covers the term "consisting of", but is not limited to it.

It will be understood that variations may be made to the foregoing embodiments of the invention, but such variations still fall within the scope of the invention. Unless stated otherwise, alternative features used for the same, equivalent, or similar purpose may replace each feature disclosed in this specification. Thus, unless stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

All features disclosed in this specification may be combined into any combination, except for combinations in which at least some of these features and / or steps are mutually exclusive. In particular, the preferred features of the invention are applicable to all aspects of the invention and can be used in any combination. Also, features described in non-essential combinations may be used alone (not in combination).

It will be appreciated that many of the features of the particularly preferred embodiments described above are themselves inventive and not just part of an embodiment of the invention. Independent protection may be sought for these features in addition to or in place of any invention currently claimed.

The structure of the LC display according to the invention corresponds to the common geometry of a PSA display as described in the prior art cited at the outset. A geometric structure without protrusions is preferable, and in particular, the electrodes on the color filter side are unstructured and only the electrodes on the TFT side have slots of their own. Especially suitable and better for PSA-VA display The pole structure is described, for example, in US 2006/0066793 A1.

Unless otherwise specifically stated, all concentrations in this application are quoted in weight percent and refer to the overall corresponding mixture (without solvent), which contains all solid or liquid crystal components.

Unless otherwise indicated, all temperature values indicated in this application, such as melting point T (C, N), smectic (S) to nematic (N) phase transition T (S, N), and clear point T (N, I) are quoted in degrees Celsius (° C). M.p. indicates melting point, cl.p. = clear point. In addition, C = crystalline state, N = nematic phase, S = smectic phase and I = isotropic phase. The information between these symbols indicates the transition temperature.

Unless otherwise explicitly indicated in each case, all physical properties are determined or have been measured according to "Merck Liquid Crystals, Physical Properties of Liquid Crystals", Status November 1997, Merck KGaA, Germany, and are applicable to temperatures of 20 ° C And Δn was measured at 589 nm and Δε was measured at 1 kHz.

Unless otherwise explicitly indicated, the term "threshold voltage" of the present invention refers to a capacitance threshold (V ₀ ), also referred to as a Freedericks threshold. In an example, the optical threshold can also be quoted as generally common with respect to 10% relative contrast (V ₁₀ ).

Unless otherwise stated, the method of polymerizing a polymerizable compound in a PSA display as described above and below is performed at a temperature of the LC medium exhibiting a liquid crystal phase, preferably a nematic phase, and most preferably at room temperature.

Unless otherwise stated, methods for preparing test cells and measuring their electro-optical and other characteristics are performed by methods described below or similar thereto.

The display for measuring the threshold voltage of a capacitor is composed of two plane parallel glass outer plates with a distance of 25 μm, each of which has an electrode layer inside and an unfrictioned polyimide alignment layer on the top, which realizes liquid crystal The vertical edge alignment of the molecules.

The display or test unit for measuring the tilt angle consists of two flat parallel glass outer plates with a distance of 4 μm, each of which has an electrode layer inside and a polyfluorene on top An imine alignment layer, in which two polyfluorene imine layers rub against each other in parallel and achieve vertical edge alignment of liquid crystal molecules.

A polymerizable compound is polymerized in a display or a test unit by irradiating UVA light with a defined intensity for a predetermined time, wherein a voltage is applied to the display (typically 10V to 30V AC, 1kHz) at the same time. In the examples, unless otherwise indicated, polymerization was performed using a metal halide lamp and an intensity of 100 mW / cm ² . The intensity was measured using a standard UVA meter (a high-end Hoenle UV meter with a UVA sensor).

The tilt angle was measured by a crystal rotation experiment (Autronic-Melchers TBA-105). A low value here (ie a large deviation from the 90 ° angle) corresponds to a large tilt.

The VHR value was measured as follows: 0.3% polymerizable monomer compound was added to the LC host mixture, and the resulting mixture was introduced into a VA-VHR test unit (unrubbed, VA-polyimide alignment layer, LC layer thickness d). 6 μm). The HR value was measured before and after UV exposure at 1 V, 60 Hz, and 64 μs pulses after 5 minutes at 100 ° C (measurement instrument: Autronic-Melchers VHRM-105).

In the present invention and especially in the following examples, the structure of the mesogen compound is indicated by means of abbreviations, also called initials. In these prefixes, the chemical formulas are abbreviated as follows using Tables A to C below.

Use the following abbreviations: (n, m, z: 1, 2, 3, 4, 5, or 6 independently of each other)

Where n and m each represent an integer, and the three dots "..." are placeholders for other abbreviations from this table.

The following table shows the illustrative structures and their respective abbreviations. These structures and abbreviations are shown to illustrate the meaning of the abbreviation rules. In addition, it indicates a compound which is preferably used.

Table D

In a preferred embodiment of the invention, the LC medium according to the invention comprises one or more compounds selected from the group consisting of compounds from Table D.

In a preferred embodiment of the invention, the LC medium according to the invention comprises one or more compounds selected from the group consisting of compounds from Table D.

Table E

Table E shows possible palliative dopants that can be added to the LC media according to the present invention.

The LC medium preferably contains 0 to 10% by weight, especially 0.01 to 5% by weight, and particularly preferably 0.1 to 3% by weight of dopants. The LC medium preferably contains one or more dopants selected from the group consisting of compounds from Table E.

Table F

Table F shows possible stabilizers that can be added to the LC medium according to the invention.

(Where n represents an integer from 1 to 12, preferably 1, 2, 3, 4, 5, 6, 7, or 8, and no terminal methyl group is shown).

The LC medium preferably contains from 0 to 10% by weight, especially from 1 ppm to 5% by weight, particularly preferably from 1 ppm to 1% by weight of stabilizer. The LC medium preferably contains one or more stabilizers selected from the group consisting of compounds from Table F.

Table G

Table G shows illustrative compounds that can be used in the LC medium according to the invention, preferably as reactive mesogen compounds.

In a preferred embodiment of the invention, the LC medium comprises one or more compounds selected from the group of compounds from Table G.

The following examples explain the invention without limiting it. However, it shows those skilled in the art the concept of a better mixture and the compounds to be used better, their respective concentrations and their mutual combination. In addition, examples illustrate available characteristics and combinations of characteristics.

Examples

Use the following abbreviations and symbols:

General method of production test unit

The preparation of the LCD test unit started with a standard clean commercial ITO coated glass plate. Subsequently, a series of unit processes are performed on the glass substrate, including polyimide (PI) alignment film coating, PI film thermal baking, mechanical rubbing, ball spray, and UV glue distribution. After the lower and upper substrates are cleaned, a sealant is applied to the edge portions of the upper substrate. In this case, a sealant may be applied to the lower substrate. Thereafter, the lower substrate is introduced into the liquid crystal distributor, and then a predetermined amount of liquid crystal is dropped onto a predetermined portion of the lower substrate, which corresponds to a display area of the LCD. Thereafter, the lower and upper substrates are introduced into a vacuum chamber, wherein the lower substrate is combined with the upper substrate due to a vacuum pressure applied thereto, and a gap formed between the lower substrate and the upper substrate is filled with a liquid crystal material. When the sealant applied to the edge of the upper substrate is cured, the LC ODF method is completed, and the unit is studied in terms of dripping dead pixels.

Comparative example

The following liquid crystal mixture CM-1 was prepared. The composition and characteristics are given in the table below.

After the above procedure, the mixture was used in a test unit, and the results of the test unit studies on the cell gap used are summarized in the table below.

Examples

The following liquid crystal mixtures M1 to M5 were prepared by adding 0.4% -w / w of the following formula I compounds (SI1 to SI5) to the liquid crystal mixture CM-1:

After the above procedures, the mixtures M1 to M5 were used in the corresponding test cells, and the results of the test cell studies on cell gaps are summarized in the table below.

legend:

Claims (12)

An LC medium comprising one or more non-polymerizable mesogen compounds, one or more polymerizable mesogen compounds and one or more compounds of formula I, Wherein R ^a represents hydrogen or a hydrocarbon having 1 to 20 carbon atoms; R ^c represents a hydrocarbon having 1 to 20 carbon atoms; R ^b and ^Rd represent hydrogen or a hydrocarbon group having 1 to 8 carbon atoms ^; Represents -O- or a single bond, and n is an integer from 0 to 10. If the LC medium of claim 1, wherein the compounds of formula I are selected from the group of compounds of formulas A to C, Wherein R ^a , R ^b , R ^c , ^Rd and n have one of the meanings as given according to claim 1. If the LC medium of claim 1, wherein the compounds of formula I are selected from the group of compounds of formulas A1 to C4, Wherein R ^a , R ^c and n have one of the meanings given according to formula I. The LC medium of any one of claims 1 to 3, wherein the compounds of the formula I and its subformulae are selected from the group wherein R ^a represents hydrogen, methyl, ethyl, methoxy, ethoxy, phenyl , Benzyl, methylphenyl, or methoxyphenyl, and R ^c and n have one of the meanings given in claim 1. If the LC medium of any one of claims 1 to 3, wherein one or more non-polymerizable mesogen compounds are selected from the group of compounds of formula CY and / or PY, Where a is 1 or 2, and b is 0 or 1, Express or R ¹ and R ² each independently represent an alkyl group having 1 to 12 C atoms. In addition, one or two non-adjacent CH ₂ groups may pass through the -O-, -CO-, -OCO- or -COO- substitution, Z ^x and Z ^y each independently represent -CH ₂ CH _2- , -CH = CH-, -CF ₂ O-, -OCF _2- , -CH ₂ O-, -OCH _2- , -CO-O-, -O-CO-, -C ₂ F _4- , -CF = CF-, -CH = CH-CH ₂ O- or single bond, L ¹ , L ² , L ³ , and L ⁴ each independently represent F, Cl, OCF ₃ , CF ₃ , CH ₃ , CH ₂ F, and CHF ₂ . The LC medium of any one of claims 1 to 3, wherein the proportion of the polymerizable compounds in the LC medium is> 0 to <5% by weight. The LC medium of any one of claims 1 to 3, wherein the proportion of the compound of formula I in the LC medium is> 0 to <20% by weight. A method for preparing an LC medium according to any one of claims 1 to 7, comprising at least one or more non-polymerizable mesogen compounds, one or more polymerizable mesogen compounds and one or more compounds of formula I The steps. A use of an LC medium as claimed in any one of claims 1 to 7 for use in PS and PSA displays. An LC display containing an LC medium according to any one of claims 1 to 7. The LC display according to claim 10, comprising an LC unit composed of two substrates, at least one of which is transparent and at least one of the substrates has an electrode layer, and the polymerization group according to any one of claims 1 to 7 A layer of an LC medium with a low molecular weight component is located between the substrates, wherein the polymerizing component can polymerize one or more between the substrates of the LC unit in the LC medium by applying a voltage. Obtained by polymerizing a mesogen compound. A method for producing an LC display as claimed in claim 10 or 11, comprising at least providing a LC medium as claimed in any one of claims 1 to 7 by a liquid crystal drip filling method on a first substrate , And then the steps of assembling the LC unit.