TW202018065A - Liquid-crystalline medium - Google Patents

Abstract

The invention relates to a liquid-crystalline medium which comprises at least one compound of the formula X, and one or more compounds selected from the group of the compounds of the formulae IIA, IIB and IIC, wherein the occurring groups and parameters have the meanings indicated in claim 1, and to the use thereof for an active-matrix display, in particular based on the VA, PSA, PA-VA, SS-VA, SA-VA, PS-VA, PALC, IPS, PS-IPS, UB-FFS, U-IPS, FFS or PS-FFS effect.

Description

Liquid crystal medium

其中 R^X1 及R^X2 各彼此獨立地表示H、具有1至15個C原子之烷基或烷氧基，其中另外，該等基團中之一或多個CH₂ 基團可以使得O原子彼此不直接連接之方式各彼此獨立地經-C≡C-、-CF₂ O-、-OCF₂ -、-CH=CH-、

、

、-O-、-CO-O-、-O-CO-置換，且其中另外，一或多個H原子可經鹵素置換， n      表示0或1，且 Z^X1 在每次出現時彼此獨立地表示-CO-O-、-O-CO-、-CF₂ O-、 -OCF₂ -、-CH₂ O-、-OCH₂ -、-CH₂ -、-CH₂ CH₂ -、-(CH₂ )₄ -、-CH=CH-CH₂ O-、-C₂ F₄ -、-CH₂ CF₂ -、-CF₂ CH₂ -、-CF=CF-、-CH=CF-、-CF=CH-、-CH=CH-、-C≡C-或單鍵，及 視情況，必定較佳地，一或多種式I化合物：

其中 R¹¹ 及R¹² 各彼此獨立地表示H、具有1至15個C原子之烷基或烷氧基，其中另外，該等基團中之一或多個CH₂ 基團可以使得O原子彼此不直接連接之方式各彼此獨立地經-C≡C-、-CF₂ O-、-OCF₂ -、-CH=CH-、

、

、-O-、-CO-O-、-O-CO-置換，且其中另外，一或多個H原子可經鹵素置換，

在每次出現時彼此獨立地表示 a)     1,4-伸環己烯基或1,4-伸環己基，其中一或兩個不相鄰CH₂ 基團可經-O-或-S-置換， b)     1,4-伸苯基，其中一或兩個CH基團可經N置換， c)     來自哌啶-1,4-二基、1,4-雙環[2.2.2]伸辛基、萘-2,6-二基、十氫萘-2,6-二基、1,2,3,4-四氫萘-2,6-二基、菲-2,7-二基及茀-2,7-二基之群的基團， 其中基團a)、b)及c)可經鹵素原子單取代或多取代， a      為0、1或2，較佳地0或1， Z¹ 在每次出現時彼此獨立地表示-CO-O-、-O-CO-、-CF₂ O-、     -OCF₂ -、-CH₂ O-、-OCH₂ -、-CH₂ -、-CH₂ CH₂ -、-(CH₂ )₄ -、-CH=CH-CH₂ O-、-C₂ F₄ -、-CH₂ CF₂ -、-CF₂ CH₂ -、-CF=CF-、-CH=CF-、-CF=CH-、-CH=CH-、-C≡C-或單鍵，且 L¹¹ 及L¹² 各彼此獨立地表示F、Cl、CF₃ 或CHF₂ ，較佳地表示H或F，最佳地表示F， 及一或多種選自式IIA、IIB及IIC之化合物之群的化合物：

其中 R^2A 、R^2B 及R^2C 各彼此獨立地表示H、具有至多15個C原子的未經取代、經CN或CF₃ 單取代或至少經鹵素單取代的烷基或烯基，其中另外，該等基團中之一或多個CH₂ 基團可以使得O原子彼此不直接連接之方式經 -O-、-S-、

、-C≡C-、-CF₂ O-、-OCF₂ -、-OC-O-或-O-CO-置換， L¹ 至L⁴ 各彼此獨立地表示F、Cl、CF₃ 或CHF₂ ， Z² 及Z^{2 '} 各彼此獨立地表示單鍵、-CH₂ CH₂ -、-CH=CH-、-CF₂ O-、-OCF₂ -、-CH₂ O-、-OCH₂ -、-COO-、-OCO-、-C₂ F₄ -、-CF=CF-、-CH=CHCH₂ O-， p      表示0、1或2， q      表示0或1，且 v      表示1至6。The invention relates to a liquid crystal medium, which comprises one or more compounds of formula X:

Wherein R ^X1 and R ^X2 each independently represent H, an alkyl group or an alkoxy group having 1 to 15 C atoms, and in addition, one or more of the CH ₂ groups in these groups can cause O atoms to each other The method of not directly connecting each other independently through -C≡C-, -CF ₂ O-, -OCF ₂ -, -CH=CH-,

,

, -O-, -CO-O-, -O-CO-, and wherein, in addition, one or more H atoms can be replaced by halogen, n represents 0 or 1, and Z ^X1 is independent of each other at each occurrence -CO-O-, -O-CO-, -CF ₂ O-, -OCF ₂ -, -CH ₂ O-, -OCH ₂ -, -CH ₂ -, -CH ₂ CH ₂ -, -(CH ₂ ) ₄ -, -CH=CH-CH ₂ O-, -C ₂ F ₄ -, -CH ₂ CF ₂ -, -CF ₂ CH ₂ -, -CF=CF-, -CH=CF-, -CF =CH-, -CH=CH-, -C≡C- or single bond, and as the case may be, preferably, one or more compounds of formula I:

Wherein R ¹¹ and R ¹² each independently represent H, an alkyl group or an alkoxy group having 1 to 15 C atoms, and in addition, one or more of the CH ₂ groups in these groups may cause O atoms to each other The method of not directly connecting each other independently through -C≡C-, -CF ₂ O-, -OCF ₂ -, -CH=CH-,

,

, -O-, -CO-O-, -O-CO-, and wherein, in addition, one or more H atoms may be replaced by halogen,

Each occurrence independently of one another represents a) 1,4-cyclohexenyl or 1,4-cyclohexyl, where one or two non-adjacent CH ₂ groups can be passed through -O- or -S- Substitution, b) 1,4-phenylene, where one or two CH groups can be replaced by N, c) from piperidine-1,4-diyl, 1,4-bicyclo[2.2.2] octane Group, naphthalene-2,6-diyl, decalin-2,6-diyl, 1,2,3,4-tetrahydronaphthalene-2,6-diyl, phenanthrene-2,7-diyl and A group of stilbene-2,7-diyl group, wherein the groups a), b) and c) may be mono- or poly-substituted by halogen atoms, a is 0, 1 or 2, preferably 0 or 1, Z ¹ at each occurrence independently of each other represents -CO-O-, -O-CO-, -CF ₂ O-, -OCF ₂ -, -CH ₂ O-, -OCH ₂ -, -CH ₂ -, -CH ₂ CH ₂ -, -(CH ₂ ) ₄ -, -CH=CH-CH ₂ O-, -C ₂ F ₄ -, -CH ₂ CF ₂ -, -CF ₂ CH ₂ -, -CF=CF -, -CH=CF-, -CF=CH-, -CH=CH-, -C≡C- or single bond, and L ¹¹ and L ¹² each independently represent F, Cl, CF ₃ or CHF ₂ , It preferably represents H or F, most preferably F, and one or more compounds selected from the group of compounds of formulae IIA, IIB and IIC:

Wherein R ^2A , R ^2B and R ^2C each independently represent H, an unsubstituted alkyl or alkenyl group having up to 15 C atoms, mono-substituted by CN or CF ₃ or at least mono-substituted by halogen, wherein, in addition, One or more of the CH ₂ groups in these groups can make O atoms not directly connected to each other via -O-, -S-,

, -C≡C-, -CF ₂ O-, -OCF ₂ -, -OC-O- or -O-CO- substitution, L ¹ to L ⁴ each independently represent F, Cl, CF ₃ or CHF ₂ , Z ² and Z ^{2 '} each independently represent a single bond, -CH ₂ CH ₂ -, -CH=CH-, -CF ₂ O-, -OCF ₂ -, -CH ₂ O-, -OCH ₂ -, -COO-, -OCO-, -C ₂ F ₄ -, -CF=CF-, -CH=CHCH ₂ O-, p represents 0, 1 or 2, q represents 0 or 1, and v represents 1 to 6.

Such media can be used especially for electro-optic displays with active matrix addressing and IPS (coplanar switching) displays or FFS (fringe field switching) displays based on the ECB effect.

The principle of electronically controlled birefringence, ECB effect, or DAP (orientation phase deformation) effect was first described in 1971 (MF Schieckel and K. Fahrenschon, ``Deformation of nematic liquid crystals with vertical orientation in electrical fields'', Appl. Phys . Lett. 19 (1971), 3912). This was followed by the paper by J.F. Kahn (Appl. Phys. Lett. 20 (1972), 1193) and the paper by G. Labrunie and J. Robert (J. Appl. Phys. 44 (1973), 4869).

Papers by J. Robert and F. Clerc (SID 80 Digest Techn. Papers (1980), 30), papers by J. Duchene (Displays 7 (1986), 3) and papers by H. Schad (SID 82 Digest Techn. Papers (1982), 244) The display liquid crystal phase must have a high ratio value of elastic constant K ₃ /K ₁ , a high optical anisotropy Δn value and a dielectric anisotropy Δε value of ≤-0.5 in order to be suitable for ECB-based effects High information display components. The electro-optic display element based on the ECB effect has vertical edge alignment (VA technology = vertical alignment ( v ertically a ligned)). Dielectric negative liquid crystal media can also be used for displays using the so-called IPS or FFS effect.

In addition to IPS (coplanar conversion type; i n- p lane s witching) displays (eg Yeo, SD, paper 15.3: "An LC Display for the TV Application", SID 2004 International Symposium, Digest of Technical Papers, XXXV, book II, pp. 758 and second 759) and the already known TN (twisted nematic; T than wisted n ematic) display, for example, MVA (multi-domain vertical alignment; m ulti-domain v ertical a lignment), For example: Yoshide, H. et al., Paper 3.1: "MVA LCD for Notebook or Mobile PCs...", SID 2004 International Symposium, Digest of Technical Papers, XXXV, Volume I, pages 6 to 9 and Liu , CT et al., Paper 15.1: "A 46-inch TFT-LCD HDTV Technology...", SID 2004 International Symposium, Digest of Technical Papers, XXXV, Volume II, pages 750 to 753), PVA ( the patterned vertical alignment; p atterned v ertical a lignment) , for example: Kim, Sang Soo, paper 15.4: "Super PVA Sets New State-of- the-Art for LCD-TV ", SID 2004 International Symposium, Digest of Technical Papers, XXXV, Volume II, pages 760 to 763), ASV (Advanced Large Perspective; a dvanced s uper v iew), for example: Shigeta, Mitzuhiro and Fukuoka, Hirofumi, Paper 15.2: "Development of High Quality LCDTV '', SID 2004 International Symposium, Digest of Technical Papers, XXXV, Volume II, pages 754 to 757) mode uses EC B Effect of display, such as a so-called VAN (vertically aligned nematic type; v ertically a ligned n ematic) ) display, has established itself as the three most important of this newer type liquid crystal display device (in particular for television applications) one. These technologies are in general forms such as Souk, Jun, SID Seminar 2004, Seminar M-6: "Recent Advances in LCD Technology", Seminar Lecture Notes, M-6/1 to M-6/26, and Miller, Ian, SID Seminar 2004, Seminar M-7: "LCD-Television", Seminar Lecture Notes, M-7/1 to M-7/32 for comparison. Although the response time of modern ECB monitors has been significantly improved by addressing methods that use excitation, such as: Kim, Hyeon Kyeong et al., Paper 9.1: "A 57-in. Wide UXGA TFT-LCD for HDTV Application", SID 2004 International Symposium, Digest of Technical Papers, XXXV, Volume I, pages 106 to 109, but the achievement of video-compatible response time, especially regarding grayscale switching, is still a problem that has not yet been satisfactorily resolved.

The industrial application of this effect in electro-optic display elements requires LC phases that must meet various requirements. Here, chemical resistance to moisture, air, and physical influences (such as heat, infrared, visible light, and ultraviolet radiation, as well as DC and AC electric fields) is particularly important.

In addition, the LC phase that is industrially available is required to have a liquid crystal mesophase in a suitable temperature range and low viscosity.

A series of compounds disclosed to date with a liquid crystal mesophase do not include a single compound that meets all these requirements. Therefore, a mixture of two to 25, preferably three to 18 compounds is generally prepared to obtain a substance that can be used as an LC phase. However, it is impossible to easily prepare the optimal phase in this way, because liquid crystal materials having significantly negative dielectric anisotropy and sufficient long-term stability have not been obtained so far.

Matrix liquid crystal displays (MLC displays) are known. Non-linear elements that can be used for individual switching of individual pixels are, for example, active elements (ie, transistors). The term "active matrix" is then used, where there can be differences between the following two types: 1. MOS (metal oxide semiconductor) transistors on silicon wafers as substrates 2. Thin-film transistor (TFT) on the glass plate is used as the substrate.

In the case of type 1, the electro-optic effect used is usually dynamic scattering or guest-host effect. The use of monocrystalline silicon as the substrate material limits the size of the display, because even various module assemblies of some displays can cause problems at the joints.

In the case of the more promising type 2 (which is better), the electro-optic effect used is usually the TN effect.

The following two technologies differ: TFTs containing compound semiconductors such as CdSe, or TFTs based on polycrystalline or amorphous silicon. The latter technology is widely used all over the world.

The TFT matrix is applied inside one glass plate of the display, and the other glass plate carries transparent counter electrodes inside. Compared with the size of the pixel electrode, the TFT is extremely small and has almost no adverse effect on the image. This technology can also be extended to a fully colour-capable display, in which mosaics of red, green and blue filters are arranged in such a way that the filter elements are opposed to the switchable pixels.

The term MLC display herein encompasses any matrix display with integrated non-linear elements, that is, in addition to active matrix, the display also has passive elements, such as varistor or diode (MIM=metal-insulator-metal).

This type of MLC display is particularly suitable for TV applications (such as pocket TVs) or high-information displays in automobile or aircraft construction. In addition to the angle dependence of the contrast and response time, the specific resistance of the liquid crystal mixture is not high enough, which also causes difficulties in MLC displays [TOGASHI, S., SEKIGUCHI, K., TANABE, H., YAMAMOTO, E. , SORIMACHI, K., TAJIMA, E., WATANABE, H., SHIMIZU, H., Proc. Eurodisplay 84, September 1984: A 210-288 Matrix LCD Controlled by Double Stage Diode Rings, page 141 and below, Paris; STROMER, M., Proc. Eurodisplay 84, September 1984: Design of Thin Film Transistors for Matrix Addressing of Television Liquid Crystal Displays, page 145 and below, Paris]. As the resistance decreases, the contrast of the MLC display deteriorates. Since the specific resistance of the liquid crystal mixture generally decreases with the life of the MLC display due to interaction with the inner surface of the display, high (initial) resistance is extremely important for displays that must have acceptable resistance values over a long period of operation.

There is still a large demand for MLC displays with a very high specific resistance while having a large operating temperature range, short response time, and low threshold voltage, which can produce various gray levels.

The disadvantages of commonly used MLC-TN displays are due to their relatively low contrast, relatively high viewing angle dependence, and the difficulty of producing grayscale in these displays.

The market for VA, PS-VA, IPS, FFS and UB-FFS applications is looking for LC mixtures with fast response time and extremely high reliability. One method for achieving a fast response time is to identify highly polar LC materials with low rotational viscosity, whose use in LC mixtures promotes the desired effect. However, especially after exposure, the use of this type of highly polar LC material has an adverse effect on reliability parameters.

The present invention is based on the goal of providing liquid crystal mixtures based on ECB, UB-FFS, IPS or FFS effects, especially for monitor and TV applications, which do not have the disadvantages indicated above, or only have a reduced degree The shortcomings indicated in the article. In particular, it must be ensured that monitors and TVs also work at extremely high and low temperatures, and at the same time have very short response times and at the same time have improved reliability characteristics, especially after long operation time does not show image retention or show significant Reduced image retention.

在歐洲專利申請案第EP 17161352.4中經提及作為液晶介質之成分。亦揭示式

及式

。 然而，僅以下單種化合物用於彼文獻之介質中：

， 其中n為2及m為5。Compounds of the following general formula

It is mentioned in European Patent Application No. EP 17161352.4 as a component of a liquid crystal medium. Revelation

Pass

. However, only the following single compounds are used in the media of that literature:

, Where n is 2 and m is 5.

Therefore, the present invention relates to a liquid crystal medium comprising at least one compound of formula X and one or more compounds selected from the group of compounds of formulas IIA, IIB and IIC. These media are particularly suitable for obtaining liquid crystal displays that exhibit fast response time and good voltage retention and excellent storage stability at deep temperatures sufficient for many applications.

The mixture according to the invention preferably exhibits a very wide nematic phase range (where the clear point is ≥ 70°C, preferably ≥ 75°C, especially ≥ 80°C), a very favorable capacitance threshold, and a relatively high retention Rate value and excellent low temperature stability at -20℃ and -30℃ at the same time, as well as extremely low rotational viscosity value and short response time. In addition to the improvement in rotational viscosity γ ₁ , the mixture according to the invention also stands out in that a relatively high value of the elastic constant K ₃₃ for improving the response time can be observed. The compound of formula X is used in an LC mixture, preferably an LC mixture with negative dielectric anisotropy, to reduce the ratio of rotational viscosity γ ₁ and elastic constant K _i .

The following indicates some preferred embodiments of the mixture according to the invention.

In the compound of formula X, R ^X1 and R ^X2 preferably each independently represent: linear alkyl, especially CH ₃ , n -C ₂ H ₅ , n -C ₃ H ₇ , n -C ₄ H ₉ , n -C ₅ H ₁₁ , n -C ₆ H ₁₃ -or n -C ₇ H ₁₅ ; linear alkoxy, especially CH ₃ -O, n -C ₂ H ₅ -O, n -C ₃ H _7- O, n -C ₄ H ₉ -O, n -C ₅ H ₁₁ -O or n -C ₆ H ₁₃ -O; in addition, alkenyl, especially CH ₃ =CH, CH ₃ CH=CH, CH ₃ CH= CHCH ₂ or CH ₃ CH ₂ CH=CH; branched chain alkoxy, especially (CH ₃ ) ₂ CH(CH ₂ ) ₃ O; and alkenyloxy, especially CH ₂ =CHO, CH ₂ =CH ₂ CHO, CH ₃ CH ₂ =CHCHO or O CH ₂ CH ₂ CH=CHCH ₂ O.

R ^X1 particularly preferably represents a linear alkyl group having 1 to 7 C atoms, and R ^X2 particularly preferably represents a linear alkoxy group having 1 to 6 C atoms, especially methoxy, ethoxy, propylene Oxy, butoxy, pentyloxy or hexyloxy.

其中該等參數具有上文所給出之各別含義，且 R^X1 較佳地為烷基或烷氧基，且 R^X2 較佳地為烷氧基。Preferred compounds of formula X present in the medium are compounds of formula X-1 and X-2:

Wherein these parameters have the respective meanings given above, and R ^{X1 is} preferably alkyl or alkoxy, and R ^{X2 is} preferably alkoxy.

。Preferred compounds of formula X-1 present in the medium are compounds of formula X-1-1 and X-1-3:

.

。Preferred compounds of formula X-2 present in the media are compounds of formula X-2-1 and X-2-3:

.

In the compound of formula I, R ¹¹ and R ¹² preferably each independently represent: linear alkyl, especially CH ₃ , n -C ₂ H ₅ , n -C ₃ H ₇ , n -C ₄ H ₉ , n -C ₅ H ₁₁ , n -C ₆ H ₁₃ -or n -C ₇ H ₁₅ ; linear alkoxy, especially CH ₃ -O, n -C ₂ H ₅ -O, n -C ₃ H _7- O, n -C ₄ H ₉ -O, n -C ₅ H ₁₁ -O or n -C ₆ H ₁₃ -O; in addition, alkenyl, especially CH ₃ =CH, CH ₃ CH=CH, CH ₃ CH= CHCH ₂ or CH ₃ CH ₂ CH=CH; branched chain alkoxy, especially (CH ₃ ) ₂ CH(CH ₂ ) ₃ O; and alkenyloxy, especially CH ₂ =CHO, CH ₂ =CH ₂ CHO, CH ₃ CH ₂ =CHCHO or O CH ₂ CH ₂ CH=CHCH ₂ O.

R ¹¹ particularly preferably represents a linear alkyl group having 1 to 7 C atoms, and R ¹² particularly preferably represents a linear alkoxy group having 1 to 6 C atoms, especially methoxy, ethoxy, propoxy , Butoxy, pentyloxy or hexyloxy.

Both L ¹¹ and L ^{12 in} Formula I preferably represent F.

其中 該等參數具有上文所給出之含義，R¹¹ 表示直鏈烷基，且R¹² 較佳地表示烷氧基，且L¹¹ 及L¹² 較佳地均表示F。Preferred compounds of formula I present in the medium are formulas I-1 to I-3, preferably compounds of formula I-2:

Wherein these parameters have the meanings given above, R ¹¹ represents a linear alkyl group, and R ¹² preferably represents an alkoxy group, and L ¹¹ and L ^{12 both} preferably represent F.

其中該等參數具有上文所給出之該等含義。In a preferred embodiment, the medium comprises one or more compounds of formula I selected from the group of compounds of formulas IO-1 to IO-3, preferably compounds of formula IO-2:

The parameters have the meanings given above.

其中該等參數具有上文所給出之該等含義。In another preferred embodiment, the media comprise one or more compounds of formula I selected from the group of compounds of formula IS-1 to IS-3, preferably compounds of formula IS-2:

The parameters have the meanings given above.

其中該等參數具有上文所給出之含義，且較佳地R¹¹ 及R¹² 中之一者為烷氧基且更佳地其均為烷氧基。Preferred compounds of formula I present in the medium are compounds of formula I-4:

Wherein these parameters have the meanings given above, and preferably one of R ¹¹ and R ¹² is an alkoxy group and more preferably they are both alkoxy groups.

其中該等參數具有上文所給出之含義，且較佳地R¹¹ 及R¹² 中之一者為烷氧基且更佳地其均為烷氧基。Preferred compounds of formula I present in the medium are compounds of formula IO-4:

Wherein these parameters have the meanings given above, and preferably one of R ¹¹ and R ¹² is an alkoxy group and more preferably they are both alkoxy groups.

其中該等參數具有上文所給出之含義，且較佳地R¹¹ 及R¹² 中之一者為烷氧基且更佳地其均為烷氧基。Preferred compounds of formula I present in the medium are compounds of formula IS-4:

Wherein these parameters have the meanings given above, and preferably one of R ¹¹ and R ¹² is an alkoxy group and more preferably they are both alkoxy groups.

In a preferred embodiment of the present invention, the media comprise one or more compounds of the group of compounds of formula IO-1 to IO-3 and one or more groups of compounds selected from the group of formula IS-1 to IS-3 compound of.

The compounds of formula I can be prepared as known to experts.

The compounds of formula I can be prepared, for example, as described in US 2005/0258399 or WO 02/055463 A1.

The medium according to the invention preferably comprises one, two, three, four or more, preferably one, two or three compounds of formula I.

The compound of formula X is preferably used in the liquid crystal medium in an amount of ≥1% by weight, preferably ≥3% by weight, based on the mixture as a whole. Particularly preferred is a liquid crystal medium containing one or more compounds of formula I in an amount of 1 to 40% by weight, and very preferably 2 to 30% by weight.

The compound of formula I is preferably used in the liquid crystal medium in an amount of ≥1% by weight, preferably ≥3% by weight, based on the mixture as a whole. Particularly preferred is a liquid crystal medium containing one or more compounds of formula I in an amount of 1 to 40% by weight, and very preferably 2 to 30% by weight.

The preferred embodiment of the liquid crystal medium according to the present invention is indicated as follows: a) Liquid crystal media containing one or more compounds selected from the group of compounds of formulas IIA, IIB and IIC,

In the compounds of formulas IIA and IIB, Z ² may have the same or different meanings. In the compound of formula IIB, Z ² and Z ^2′ may have the same or different meanings.

In the compounds of formulae IIA, IIB and IIC, R ^2A , R ^2B and R ^2C each preferably represent an alkyl group having 1 to 6 C atoms, especially CH ₃ , C ₂ H ₅ , nC ₃ H ₇ , nC ₄ H ₉ , nC ₅ H ₁₁ .

In the compounds of formulae IIA and IIB, L ¹ , L ² , L ³ and L ⁴ preferably represent L ¹ = L ² = F and L ³ = L ⁴ = F, further representing L ¹ = F and L ² = Cl, L ¹ = Cl and L ² = F, L ³ = F and L ⁴ = Cl, L ³ = Cl and L ⁴ = F. In formulae IIA and IIB, Z ² and Z ^2′ preferably each independently represent a single bond, and further represent a —C ₂ H ₄ — bridge.

If in the formula ^{_{IIB, Z 2 = -C 2 H 4}} - or -CH ₂ O-, then Z ^{2 'is} preferably a single bond or, if ^{_{Z 2' = -C 2 H 4}} - or -CH ₂ O- , Then Z ^{2 is} preferably a single bond. In the compounds of the formulae IIA and IIB, (O)C _v H _2v+1 preferably represents OC _v H _2v+1 and further represents C _v H _2v+1 . In the compound of formula IIC, (O)C _v H _2v+1 preferably represents C _v H _2v+1 . In the compound of formula IIC, L ³ and L ⁴ preferably each represent F.

其中 烷基及烷基* 各彼此獨立地表示具有1至6個C原子之直鏈烷基，且 烯基及烯基* 各彼此獨立地表示具有2至6個C原子之直鏈烯基。Preferred compounds of formula IIA, IIB and IIC are indicated as follows:

Wherein alkyl and alkyl* each independently represent a linear alkyl group having 1 to 6 C atoms, and alkenyl and alkenyl* each independently represent a linear alkenyl group having 2 to 6 C atoms.

A particularly preferred mixture according to the invention comprises one or more formulas IIA-2, IIA-8, IIA-14, IIA-26, II-28, IIA-33, IIA-39, IIA-45, IIA-46, IIA- 47. Compounds of IIA-50, IIB-2, IIB-11, IIB-16 and IIC-1.

The proportion of the compound of formula IIA and/or IIB in the mixture as a whole is preferably at least 20% by weight.

其中烷基及烷基^* 具有上文所指示之含義，較佳地以＞3重量%、尤其＞5重量%且尤佳5至25重量%之量。 b)     另外包含一或多種式III化合物的液晶介質：

其中 R³¹ 及R³² 各彼此獨立地表示具有至多12個C原子之直鏈烷基、烷氧基、烯基、烷氧基烷基或烷氧基，且

表示

Z³ 表示單鍵、-CH₂ CH₂ -、-CH=CH-、-CF₂ O-、-OCF₂ -、-CH₂ O-、-OCH₂ -、-COO-、-OCO-、-C₂ F₄ -、-C₄ H₈ -、-CF=CF-。A particularly preferred medium according to the invention contains at least one compound of formula IIC-1:

Wherein alkyl and alkyl ^* have the meaning indicated above, preferably in an amount >3% by weight, especially >5% by weight and particularly preferably 5 to 25% by weight. b) Liquid crystal media additionally containing one or more compounds of formula III:

Wherein R ³¹ and R ³² each independently represent a straight-chain alkyl group having at most 12 C atoms, an alkoxy group, an alkenyl group, an alkoxyalkyl group or an alkoxy group, and

Express

Z ³ represents a single bond, -CH ₂ CH ₂ -, -CH=CH-, -CF ₂ O-, -OCF ₂ -, -CH ₂ O-, -OCH ₂ -, -COO-, -OCO-,- C ₂ F ₄ -, -C ₄ H ₈ -, -CF=CF-.

其中 烷基及烷基* 各彼此獨立地表示具有1至6個C原子之直鏈烷基。Preferred compounds of formula III are indicated below:

Wherein alkyl and alkyl* each independently represent a linear alkyl group having 1 to 6 C atoms.

The medium according to the invention preferably comprises at least one compound of formula IIIa and/or formula IIIb.

及/或

及/或

， 較佳地總量為≥5重量%、尤其≥10重量%。The proportion of the compound of formula III in the mixture as a whole is preferably at least 5% by weight. c) Liquid crystal media containing compounds of the following formula:

And/or

And/or

, The total amount is preferably ≥5 wt%, especially ≥10 wt%.

， 較佳地量為2至15重量%。In addition, the mixture according to the present invention preferably containing the following compound (abbreviation: CC-3-V1):

The preferred amount is 2 to 15% by weight.

。The preferred mixture contains 5 to 60% by weight, preferably 10 to 55% by weight, especially 20 to 50% by weight of the compound of the formula (abbreviation: CC-3-V):

.

及下式化合物(縮寫字：CC-3-V1)：

之混合物， 較佳地量為10至60重量%。 d)     另外包含一或多種下式之四環化合物的液晶介質：

其中 R^7-10 各彼此獨立地具有請求項5中關於R^2A 所指示之含義之一，且 w及x 各彼此獨立地表示1至6。In addition, it is preferable to include a compound of the following formula (abbreviation: CC-3-V):

And the compound of the following formula (abbreviation: CC-3-V1):

The amount of the mixture is preferably 10 to 60% by weight. d) Liquid crystal media containing one or more tetracyclic compounds of the following formula:

Wherein R ^7-10 each independently have one of the meanings indicated for R ^{2A in} claim 5, and w and x independently represent 1 to 6 each other.

其中R¹⁴ 至R¹⁹ 各彼此獨立地表示具有1至6個C原子之烷基或烷氧基；z及m各彼此獨立地表示1至6；x表示0、1、2或3。Particularly preferred is a mixture containing at least one compound of formula V-9. e) Liquid crystal media additionally containing one or more compounds of formula Y-1 to Y-6:

Wherein R ¹⁴ to R ¹⁹ each independently represent an alkyl group or alkoxy group having 1 to 6 C atoms; z and m each independently represent 1 to 6; x represents 0, 1, 2 or 3.

其中 R表示具有1至6個C原子之直鏈烷基或烷氧基，且m=0、1、2、3、4、5或6，且n表示0、1、2、3或4。The medium according to the invention particularly preferably contains one or more compounds of formulae Y-1 to Y-6, the amount of which is preferably ≥5% by weight. f) Liquid crystal media containing one or more fluorinated terphenyls of formulas T-1 to T-21:

Where R represents a linear alkyl or alkoxy group having 1 to 6 C atoms, and m=0, 1, 2, 3, 4, 5, or 6, and n represents 0, 1, 2, 3, or 4.

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

The medium according to the invention preferably contains the biphenyls of the formulae T-1 to T-21 in an amount of 2 to 30% by weight, in particular 5 to 20% by weight.

Especially preferred are compounds of formulae T-1, T-2, T-4, T-20 and T-21. In these compounds, R preferably represents an alkyl group each having 1 to 5 C atoms, and further represents an alkoxy group. In the compound of formula T-20, R preferably represents alkyl or alkenyl, especially alkyl. In the compound of formula T-21, R preferably represents an alkyl group.

其中 烷基及烷基^* 各彼此獨立地表示具有1至6個C原子之直鏈烷基，且 烯基及烯基^* 各彼此獨立地表示具有2至6個C原子之直鏈烯基。If the Δn value of the mixture is ≥ 0.1, triphenylene is preferably used in the mixture according to the invention. The preferred mixture contains 2 to 20% by weight of one or more triphenyl compounds selected from the group of T-1 to T-21 compounds. g) Liquid crystal media additionally containing one or more biphenyls of formula B-1 to B-3:

Wherein alkyl and alkyl ^* each independently represent a linear alkyl group having 1 to 6 C atoms, and alkenyl and alkenyl ^* each independently represent a linear alkenyl group having 2 to 6 C atoms.

The proportion of the biphenyls of formulae B-1 to B-3 in the mixture as a whole is preferably at least 3% by weight, especially ≥5% by weight.

Among the compounds of the formulae B-1 to B-3, the compound of the formula B-2 is particularly preferred.

， 其中烷基^* 表示具有1至6個C原子之烷基。根據本發明之介質尤佳地包含一或多種式B-1a及/或B-2c之化合物。 h)     包含至少一種式Z-1至Z-7之化合物的液晶介質：

其中R及烷基具有上文所指示之含義。 i)     另外包含至少一種式O-1至O-18之化合物的液晶介質：

其中R¹ 及R² 具有關於R^2A 所指示之含義。R¹ 及R² 較佳地各彼此獨立地表示直鏈烷基或烯基。Youjia's biphenyl is

, Where alkyl ^* represents an alkyl group having 1 to 6 C atoms. The medium according to the invention particularly preferably contains one or more compounds of the formulae B-1a and/or B-2c. h) Liquid crystal media containing at least one compound of formulae Z-1 to Z-7:

Where R and alkyl have the meaning indicated above. i) Liquid crystal media additionally containing at least one compound of formulae O-1 to O-18:

Where R ¹ and R ² have the meanings indicated for R ^2A . R ¹ and R ² preferably each independently represent a linear alkyl group or alkenyl group.

Preferred media include one or more formulas O-1, O-3, O-4, O-6, O-7, O-10, O-11, O-12, O-14, O-15, O- 16 and/or O-17 compounds.

It particularly preferably comprises one or more compounds selected from the group of compounds of formula O-17.

The mixture according to the invention very particularly preferably contains compounds of the formulae O-10, O-12, O-16 and/or O-17, especially in amounts of 5% to 30%.

。Preferred compounds of formulae O-10 and O-17 are indicated as follows:

.

The medium according to the invention particularly preferably comprises tricyclic compounds of formula O-10a and/or formula O-10b and one or more bicyclic compounds of formula O-17a to O-17d. The total proportion of compounds of formula O-10a and/or O-10b and one or more compounds selected from bicyclic compounds of formula O-17a to O-17d is 5% to 40%, particularly preferably 15% to 35% .

。Very particularly preferred mixtures include compounds O-10a and O-17a:

.

Based on the mixture as a whole, the compounds O-10a and O-17a are preferably present in the mixture at a concentration of 15% to 35%, particularly preferably 15% to 25%, and particularly preferably 18% to 22% .

。A very good mixture contains compounds O-10b and O-17a:

.

Based on the mixture as a whole, the compounds O-10b and O-17a are preferably present in the mixture at a concentration of 15% to 35%, particularly preferably 15% to 25%, and particularly preferably 18% to 22% .

。A very good mixture contains the following three compounds:

.

Based on the mixture as a whole, the compounds O-10a, O-10b and O-17a are preferably at a concentration of 15% to 35%, particularly preferably 15% to 25%, and particularly preferably 18% to 22% Exist in the mixture.

， 其中R¹ 及R² 具有上文所指示之含義。較佳地，在化合物O-6、O-7及O-17中，R¹ 表示分別具有1至6個或2至6個C原子之烷基或烯基，且R² 表示具有2至6個C原子之烯基。Preferred mixtures include at least one compound selected from the group of compounds:

, Where R ¹ and R ² have the meaning indicated above. Preferably, in compounds O-6, O-7 and O-17, R ¹ represents an alkyl or alkenyl group having 1 to 6 or 2 to 6 C atoms, respectively, and R ² represents a group having 2 to 6 C-alkenyl.

其中烷基表示具有1至6個C原子之烷基。Preferred mixtures include at least one compound of formula O-6a, O-6b, O-7a, O-7b, O-17e, O-17f, O-17g, and O-17h:

Wherein alkyl means an alkyl having 1 to 6 C atoms.

其中R^1N 及R^2N 各彼此獨立地具有關於R^2A 所指示之含義，較佳地表示直鏈烷基、直鏈烷氧基或直鏈烯基，且 Z¹ 及Z² 各彼此獨立地表示-C₂ H₄ -、-CH=CH-、-(CH₂ )₄ -、-(CH₂ )₃ O-、-O(CH₂ )₃ -、-CH=CHCH₂ CH₂ -、-CH₂ CH₂ CH=CH-、-CH₂ O-、-OCH₂ -、-COO-、-OCO-、-C₂ F₄ -、-CF=CF-、-CF=CH-、-CH=CF-、-CF₂ O-、-OCF₂ -、-CH₂ -或單鍵。 k)     較佳混合物包含一或多種選自式BC之二氟二苯并色滿化合物、式CR之色滿、式PH-1及PH-2之氟化菲、式BF-1及BF-2之氟化二苯并呋喃之群的化合物：

其中 R^B1 、R^B2 、R^CR1 、R^CR2 、R¹ 、R² 各彼此獨立地具有R^2A 之含義。c為0、1或2且d表示1或2。R¹ 及R² 較佳彼此獨立地表示具有1至6個C原子之烷基或烷氧基。式BF-1及BF-2之化合物不應等同於一或多種式I化合物。The compounds of formulae O-6, O-7 and O-17e-h are preferably present in an amount of 1 to 40% by weight, preferably 2 to 35% by weight and very particularly preferably 2 to 30% by weight In the mixture according to the invention. j) The preferred liquid crystal medium according to the invention comprises one or more substances containing tetrahydronaphthyl or naphthyl units, such as compounds of formulae N-1 to N-5:

Wherein R ^1N and R ^2N each independently have the meaning indicated with respect to R ^2A , preferably represents a linear alkyl group, a linear alkoxy group or a linear alkenyl group, and Z ¹ and Z ² each independently represent each other -C ₂ H ₄ -, -CH=CH-, -(CH ₂ ) ₄ -, -(CH ₂ ) ₃ O-, -O(CH ₂ ) ₃ -, -CH=CHCH ₂ CH ₂ -, -CH ₂ CH ₂ CH=CH-, -CH ₂ O-, -OCH ₂ -, -COO-, -OCO-, -C ₂ F ₄ -, -CF=CF-, -CF=CH-, -CH=CF -, -CF ₂ O-, -OCF ₂ -, -CH ₂ -or single bond. k) The preferred mixture comprises one or more difluorodibenzochroman compounds of formula BC, chroman of formula CR, phenanthrene fluoride of formula PH-1 and PH-2, formula BF-1 and BF-2 Fluorinated dibenzofuran group of compounds:

Among them, R ^B1 , R ^B2 , R ^CR1 , R ^CR2 , R ¹ , and R ² each independently have the meaning of R ^2A . c is 0, 1 or 2 and d represents 1 or 2. R ¹ and R ² preferably independently of each other represent an alkyl or alkoxy group having 1 to 6 C atoms. The compounds of formula BF-1 and BF-2 should not be equivalent to one or more compounds of formula I.

The mixture according to the invention preferably comprises compounds of the formulae BC, CR, PH-1, PH-2 and/or BF in an amount of 3 to 20% by weight, in particular in an amount of 3 to 15% by weight.

其中 烷基及烷基* 各彼此獨立地表示具有1至6個C原子之直鏈烷基，且 烯基及烯基* 各彼此獨立地表示具有2至6個C原子之直鏈烯基。Particularly preferred compounds of formula BC and CR are compounds BC-1 to BC-7 and CR-1 to CR-5:

Wherein alkyl and alkyl* each independently represent a linear alkyl group having 1 to 6 C atoms, and alkenyl and alkenyl* each independently represent a linear alkenyl group having 2 to 6 C atoms.

其中 R¹¹ 、R¹² 、R¹³ 各彼此獨立地表示具有1至6個C原子之直鏈烷基、烷氧基、烷氧基烷基或烯基， R¹² 及R¹³ 另外表示鹵素，較佳地表示F，

表示

， i       表示0、1或2。Very particularly preferred is a mixture comprising one, two or three compounds of formula BC-2, BF-1 and/or BF-2. l) The preferred mixture contains one or more indane compounds of formula In:

Wherein R ¹¹ , R ¹² and R ¹³ each independently represent a linear alkyl group having 1 to 6 C atoms, an alkoxy group, an alkoxyalkyl group or an alkenyl group, and R ¹² and R ¹³ additionally represent halogen Jiadi said F,

Express

, I means 0, 1, or 2.

。Preferred compounds of formula In are compounds of formulae In-1 to In-16 as indicated below:

.

Especially preferred are compounds of formula In-1, In-2, In-3 and In-4.

其中 R、R¹ 及R² 各彼此獨立地具有如請求項5中R^2A 所指示之含義，且烷基表示具有1至6個C原子之烷基。s表示1或2。The compounds of the formula In and the sub-formulas In-1 to In-16 are preferably used in the mixture according to the invention at a concentration of ≥5% by weight, in particular 5 to 30% by weight and very particularly preferably 5 to 25% by weight. m) The preferred mixture additionally contains one or more compounds of formula L-1 to L-11:

Wherein R, R ¹ and R ² each independently have the meaning as indicated by R ^2A in claim 5, and alkyl represents an alkyl group having 1 to 6 C atoms. s represents 1 or 2.

Particularly preferred are compounds of formulae L-1 and L-4, especially L-4.

The compounds of formulae L-1 to L-11 are preferably used in concentrations of 5 to 50% by weight, especially 5 to 40% by weight and very particularly preferably 10 to 40% by weight.

The concept of a preferred mixture is indicated as follows: (The abbreviations used are explained in Table A. Here n and m each independently represent 1 to 15, preferably 1 to 6).

The mixture according to the invention preferably comprises-one or more compounds of formula X, where n=0, R ^X1 =alkyl and R ^X2 =alkoxy; and/or-one or more compounds of formula X, where n=1 , R ^X1 =alkyl and R ^X2 =alkoxy; and/or-one or more compounds of formula I, wherein L ¹¹ =L ¹² =F, R ¹ =alkyl and R ^1* =alkoxy; and/ Or-CPY-n-Om, especially CPY-2-O2, CPY-3-O2 and/or CPY-5-O2, the concentration of the mixture as a whole is preferably >5%, especially 10% to 30%, And/or-CY-n-Om, preferably CY-3-O2, CY-3-O4, CY-5-O2 and/or CY-5-O4, the concentration of which is preferably based on the mixture as a whole> 5%, especially 15% to 50%, and/or-CCY-n-Om, preferably CCY-4-O2, CCY-3-O2, CCY-3-O3, CCY-3-O1 and/or CCY -5-O2, the concentration of the mixture as a whole is preferably >5%, especially 10% to 30%, and/or-CLY-n-Om, preferably CLY-2-O4, CLY-3-O2 And/or CLY-3-O3, the concentration of the mixture as a whole is preferably >5%, especially 10% to 30%.

Furthermore, it is preferred that the mixture according to the invention comprises: (n and m each independently represent 1 to 6). -Formula X, preferably Formula X-1 and X-2, preferably Formula XOY-nm, XOY-n-Om, CXOY-nm and CXOY-n-Om (especially from formula XOY-3-2, XOY-3-O2 and XOY-3-O4, CXOY-3-1, CXOY-3-O2 and CXOY-3-O4), the concentration range is 1 to 30% by weight, more preferably 2 to 25% by weight, particularly preferably 3 to 20% by weight, and very particularly preferably 4 to 15% by weight -Formula I, if it exists, preferably Formula I-1 to I-3, ie Formula IO-1 to IO-3 and/or IS-1 to IS-3, especially LB-3-O4 and/or LB The compound of (S)-4-O3 has a concentration range of 1 to 20% by weight, more preferably 2 to 15% by weight, particularly preferably 3 to 12% by weight and very particularly preferably 4 to 11% by weight -CPY-n-Om and CY-n-Om, the concentration of the mixture as a whole is preferably 10% to 80%, And/or -For CPY-n-Om and CK-n-F, the concentration of the mixture as a whole is preferably 10% to 70%, And/or -CPY-n-Om and PY-n-Om, preferably CPY-2-O2 and/or CPY-3-O2 and PY-3-O2, the concentration of the mixture as a whole is preferably 10% to 45% , And/or -For CPY-n-Om and CLY-n-Om, the concentration of the mixture as a whole is preferably 10% to 80%, And/or -CCVC-n-V, preferably CCVC-3-V, the concentration of the mixture as a whole is preferably 2% to 10%, And/or -CCC-n-V, preferably CCC-2-V and/or CCC-3-V, the concentration of the mixture as a whole is preferably 2% to 10%, And/or -CC-V-V, its concentration is preferably 5% to 50% based on the mixture as a whole.

In a particularly preferred embodiment of the present invention, the medium contains one or more compounds selected from the group of compounds of formula XOY-n-Om and CXOY-n-Om in a concentration range of 2% to 15% and the concentration range is Compound CC-3-V within 25% to 40% and compound CC-3-V1 with concentration ranging from 5% to 12%.

In a particularly preferred embodiment of the present invention, the medium contains compounds B-2O-O5 and/or B-2O-O5 and/or B-5O-O5 in a concentration range of 2% to 8% and a concentration range of 25 Compound CC-3-V in% to 40% and compound CC-3-V1 in the concentration range of 5% to 12%.

In a particularly preferred embodiment of the present invention, the medium contains compounds B(S)-2O-O4 and/or B(S)-2O-O5 and/or B(S) in a concentration range of 2% to 8% -2O-O6 and compound CC-3-V in a concentration range of 25% to 40% and compound CC-3-V1 in a concentration range of 5% to 12%.

The present invention further relates to an electro-optic display with active matrix addressing based on the ECB, VA, PS-VA, PA-VA, IPS, PS-IPS, FFS, or PS-FFS effects, which contains items 1 to 11 according to claims One or more of the liquid crystal media are used as dielectrics.

The nematic phase of the liquid crystal medium according to the present invention is preferably ≤-20°C to ≥70°C, particularly preferably ≤-30°C to ≥80°C, and particularly preferably ≤-40°C to ≥90°C.

The expression "having a nematic phase" means in this article: on the one hand, the smectic phase and crystallization are not observed at a low temperature at the corresponding temperature, and on the other hand, the self-nematic phase does not appear clear when heated. The study at low temperature was carried out in a flow-type viscometer at the corresponding temperature and was checked by storing in a test unit with a layer thickness corresponding to the electro-optical use for at least 100 hours. If the storage stability in the corresponding test unit at a temperature of -20°C is 1000 hours or longer, the medium is said to be stable at this temperature. Under the temperature of -30℃ and -40℃, the corresponding time is 500 hours and 250 hours respectively. At high temperatures, the clear point is measured in the capillary by conventional methods.

The liquid crystal mixture preferably has a nematic phase range of at least 60 K and a flow viscosity ν ₂₀ of at most 30 mm ² ·s ^-1 at 20°C.

The birefringence Δn value in the liquid crystal mixture is generally between 0.07 and 0.16, preferably between 0.08 and 0.13.

The Δε of the liquid crystal mixture according to the present invention is -0.5 to -8.0, especially -2.5 to -6.0, where Δε represents dielectric anisotropy. The rotational viscosity γ ₁ at 20°C is preferably ≤150 mPa·s, especially ≤120 mPa·s.

The liquid crystal medium according to the invention has a relatively low threshold voltage (V ₀ ) value. It is preferably in the range of 1.7 V to 3.0 V, particularly preferably ≤2.5 V and very particularly preferably ≤2.3 V.

For the present invention, unless explicitly indicated otherwise, the term “threshold voltage” refers to the capacitance threshold (V ₀ ), also known as the Freedericks threshold.

In addition, the liquid crystal medium according to the present invention has a high voltage retention rate value in the liquid crystal cell.

Generally speaking, a liquid crystal medium with a low address voltage or threshold voltage exhibits a lower voltage retention rate than a liquid crystal medium with a higher address voltage or threshold voltage, and vice versa.

For the present invention, the term "dielectric positive compound" means a compound with Δε>1.5, the term "dielectric neutral compound" means another compound of -1.5≤Δε≤1.5, and the term "dielectric negative compound" means Δε <-1.5 of their compounds. In this paper, the dielectric anisotropy of the compound is determined by the following steps: dissolving 10% of the compound in the liquid crystal host, and measuring the capacitance of the resulting mixture in at least one test cell, the layer thickness of the test cell in each case is 20 µm and vertical and homogeneous surface alignment at 1 kHz. The measurement voltage is usually 0.5 V to 1.0 V, but it is always lower than the capacitance limit of the respective liquid crystal mixtures studied.

All temperature values indicated for the present invention are in °C.

The mixture according to the invention is suitable for all VA-TFT applications, such as VAN, MVA, (S)-PVA, ASV, PSA (polymer-maintained VA) and PS-VA (polymer-stabilized VA). It is also suitable for IPS (coplanar switching type) and FFS (fringe field switching type) applications with negative Δε.

The nematic liquid crystal mixture in the display according to the invention generally contains two components: A and B, which themselves consist of one or more individual compounds.

Component A has significantly negative dielectric anisotropy and provides dielectric anisotropy with nematic phase ≤-0.5. In addition to one or more compounds of formula X, it preferably includes compounds of formulae IIA, IIB and/or IIC, and additionally includes one or more compounds of formula O-17.

The proportion of component A is preferably between 45% and 100%, especially between 60% and 100%.

For component A, one (or more) individual compounds with Δε values ≤ -0.8 are preferably selected. It must be that the more negative this value is, the less the ratio A is in the mixture as a whole.

Component B has a distinct nematic state, and at 20°C, the flow viscosity is not greater than 30 mm ² · s ^-1 , preferably not greater than 25 mm ² · s ^-1 .

A variety of suitable materials are known to those skilled in the art from the literature. Especially preferred are compounds of formula O-17.

Particularly preferred individual compounds in component B are very low viscosity nematic liquid crystals with a flow viscosity at 20°C of not more than 18 mm ² ·s ^-1 , preferably not more than 12 mm ² ·s ^-1 .

The component B is monomorphic or interconvertible nematic, has no smectic phase and can prevent the smectic phase from appearing in the liquid crystal mixture when it is lowered to an extremely low temperature. For example, if various high-nematic materials are added to the smectic liquid crystal mixture, the nematic states of these materials can be compared by the degree of suppression of the smectic phase achieved.

The mixture may also optionally contain component C, which contains compounds having a dielectric anisotropy of Δε≧1.5. These so-called positive compounds are usually present in the mixture of negative dielectric anisotropy in an amount of ≤20% by weight based on the mixture as a whole.

In addition to one or more compounds of formula X, these phases preferably comprise 4 to 15, especially 5 to 12 and particularly preferably <10 compounds of formula IIA, IIB and/or IIC and one or more as appropriate Compound of formula O-17.

In addition to compounds of formula X and compounds of formulas IIA, IIB and/or IIC and optionally O-17, other ingredients may also be, for example, up to 45% of the mixture as a whole, but preferably up to 35%, especially up to 10% Quantity exists.

The other ingredients are preferably selected from nematic or nematic primitives, especially from the known substances of the following categories: oxyazobenzene, benzylideneaniline, biphenyl, terphenyl, phenyl benzoate Or cyclohexyl benzoate, phenyl cyclohexanecarboxylate or cyclohexyl cyclohexanecarboxylate, phenylcyclohexane, cyclohexylbiphenyl, cyclohexylcyclohexane, cyclohexylnaphthalene, 1,4-bicyclohexyl Benzene or cyclohexylpyrimidine, phenyldioxane or cyclohexyldioxane, optionally halogenated stilbene, benzylphenyl ether, diphenylacetylene and substituted cinnamate.

The most important compound suitable as a component of this type of liquid crystal phase can be characterized by the following formula IV: R ²⁰ -LGER ²¹ IV where L and E each represent a carbocyclic or heterocyclic system from the group formed by: 1,4-disubstituted Benzene ring and cyclohexane ring, 4,4'-disubstituted biphenyl, phenylcyclohexane and cyclohexylcyclohexane system, 2,5-disubstituted pyrimidine and 1,3-dioxane ring , 2,6-disubstituted naphthalene, dihydronaphthalene and tetrahydronaphthalene, quinazoline and tetrahydroquinazoline, G represents -CH=CH- -N(O)=N- -CH=CQ- -CH =N(O)- -C≡C- -CH ₂ -CH ₂ --CO-O- -CH ₂ -O- -CO-S- -CH ₂ -S- -CH=N- -COO-Phe- COO- -CF ₂ O- -CF=CF- -OCF ₂ --OCH ₂ --(CH ₂ ) ₄ --(CH ₂ ) ₃ O- or CC single bond, Q represents halogen, preferably chlorine or -CN, and R ²⁰ and R ²¹ each represent an alkyl, alkenyl, alkoxy, alkoxyalkyl or alkoxycarbonyloxy group having up to 18, preferably up to 8 carbon atoms, or the like One of the groups represents CN, NC, NO ₂ , NCS, CF ₃ , SF ₅ , OCF ₃ , F, Cl, or Br.

In most of these compounds, R ²⁰ and R ²¹ are different from each other, and one of these groups is usually an alkyl group or an alkoxy group. Other variants of the proposed substituents are also common. Many such substances or mixtures thereof are also commercially available. All such substances can be prepared by methods known from the literature.

It is self-evident for those skilled in the art that the VA, IPS or FFS mixture according to the present invention may also contain compounds that have been replaced by corresponding isotopes such as H, N, O, Cl and F.

Polymerizable compounds, such as the so-called reactive liquid crystal matrix (RM) as disclosed in US 6,861,107, can be additionally added to the mixture according to the present invention, and the concentration thereof is preferably 0.01 to 5% by weight based on the mixture, particularly preferably 0.2 to 2% by weight. These mixtures may also optionally contain initiators, as described for example in U.S. 6,781,665. Preferably, an initiator, such as Irganox-1076 from BASF, is added to the mixture containing the polymerizable compound in an amount of 0% to 1%. This type of mixture can be used in the so-called polymer-stabilized VA mode (PS-VA) or PSA (polymer-maintained VA), in which it is intended to polymerize the reactive liquid crystal radicals in the liquid crystal mixture. The prerequisite is that the liquid crystal compound of the LC host does not react under the polymerization conditions of the reactive liquid crystal matrix (ie, usually when exposed to UV in the wavelength range of 320 to 360 nm). Liquid crystal compounds containing alkenyl side chains (such as CC-3-V) do not show reaction under UV polymerization conditions (UV polymerization).

The mixture according to the present invention may additionally contain conventional additives such as stabilizers, antioxidants, UV absorbers, nanoparticles, microparticles, and the like.

The structure of the liquid crystal display according to the invention corresponds to the common geometrical structure as described in eg EP-A 0 240 379.

The following examples are intended to explain the invention without limiting it. In the above and below, the percentage data represents the weight percentage; all temperatures are expressed in degrees Celsius.

；

。Throughout the patent application, 1,4-cyclohexyl ring and 1,4-phenylene ring are depicted as follows:

;

.

Unless specifically mentioned otherwise, the cyclohexyl ring is a trans-1,4-cyclohexyl ring.

表 2 ：橋接成員

表 3 ：側鏈

Throughout the patent applications and examples, the structure of liquid crystal compounds is indicated by means of abbreviations. Unless otherwise indicated, conversion to the chemical formula is performed according to Tables 1 to 3. All groups CnH2n+1, CmH2m+1 and Cm'H2m'+1 or CnH2n and CmH2m are straight-chain alkyl groups or alkylene groups having n, m, m'or z C atoms in each case. n, m, m', z each independently represent 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12, preferably 1, 2, 3, 4, 5 Or 6. In Table 1, the ring element of each compound is coded, in Table 2, the bridging members are listed, and in Table 3, the meaning of the symbol of the left or right side chain of the compound is indicated. Table 1 : Ring elements

Table 2 : Bridge members

Table 3 : Side chain

In addition to one or more compounds of formula X, the mixture according to the invention preferably comprises one or more compounds mentioned below from Table A. Table A uses the following abbreviations: (n, m, m', z: 1, 2, 3, 4, 5, or 6 independently of each other; (O)C _m H _2m+1 means OC _m H _{2m+ 1} or C _m H _2m+1 )

The liquid crystal mixture used according to the invention can be prepared in a manner known per se. Generally speaking, it is preferable to dissolve the required amount of components used in relatively small amounts in the components constituting the main component at high temperature. It is also possible to mix the solutions of the components in an organic solvent, such as acetone, chloroform, or methanol, and remove the solvent again, for example, by distillation after thorough mixing.

With the help of suitable additives, the liquid crystal phase according to the invention can be modified so that it can be used in any type of display (such as ECB, VAN, IPS, GH or ASM-VA LCD) that has been disclosed so far.

The dielectric may also contain other additives known to those skilled in the art and described in the literature, such as UV absorbers, antioxidants, nanoparticles, and free radical scavengers. For example, 0% to 15% polychromatic dyes, stabilizers (such as phenols, HALS (hindered amine light stabilizers)), or para-dopant dopants can be added. Stabilizers suitable for the mixtures according to the invention are among others listed in Table C.

For example, a polychromatic dye of 0% to 15% can be added, and a conductive salt can also be added, preferably 4-hexyloxybenzoic acid ethyl dimethyl dodecyl ammonium, tetraphenyl borohydride Complex salts of butylammonium or crown ethers (see, for example, Haller et al., Mol. Cryst. Liq. Cryst., Vol. 24 , pages 249 to 258 (1973)) to improve conductivity, or substances can be added To modify the dielectric anisotropy, viscosity and/or alignment of the nematic phase. Substances of this type are described in, for example, DE-A 22 09 127, 22 40 864, 23 21 632, 23 38 281, 24 50 088, 26 37 430 and 28 53 728. Table B Table B indicates possible dopants that can be added to the mixture according to the invention. If the mixture contains a dopant, it is added in an amount of 0.01 to 4% by weight, preferably 0.01 to 3% by weight.

The mixture according to the invention contains at least one stabilizer from Table C given below. Table C can be added in an amount of 0 to 10% by weight, preferably 0.001 to 5% by weight, especially 0.001 to 1% by weight, for example to the stabilizer of the mixture according to the invention as indicated below.

Examples: The following examples are intended to explain the invention without limiting it. In the examples, mp represents the melting point of the liquid crystal substance (in degrees Celsius) and C represents the clear point of the liquid crystal substance (in degrees Celsius); the boiling point temperature is represented by mp. In addition: C represents a crystalline solid state, S represents a smectic phase (index represents phase type), N represents a nematic state, Ch represents a cholesterol-like liquid crystal phase, I represents an isotropic phase, and T _g represents a glass transition temperature. The number between the two symbols indicates the conversion temperature in degrees Celsius.

The host mixture used to determine the optical anisotropy Δn of the compound of formula X is the commercially available mixture ZLI-4792 (Merck KGaA). The dielectric anisotropy Δε was measured using a commercially available mixture ZLI-2857. The physical information of the compound to be studied is obtained from the change of the dielectric constant of the host mixture after addition of the compound to be studied and extrapolation to 100% of the compound used. In general, depending on the solubility, 10% of the compound to be studied is dissolved in the host mixture.

Unless otherwise indicated, parts or percentage data refers to parts by weight or percentage by weight.

Above and below: V _o represents the capacitance threshold voltage [V] at 20°C, n _e represents the unusual refractive index at 20°C and 589 nm, n _o represents the temperature at 20°C and 589 nm Ordinary refractive index, Δn represents the optical anisotropy at 20°C and 589 nm, ε _⊥ represents the dielectric permittivity perpendicular to the _director at 20°C and 1 kHz, ε _÷÷ represents at 20°C and 1 kHz Under, the dielectric permittivity parallel to the director, Δε represents the dielectric anisotropy at 20℃ and 1 kHz, cl.p. and T(N,I) represent the clear point [℃], γ ₁ refers to Rotational viscosity [mPa·s] measured at 20°C, which is measured in a magnetic field by a rotation method, K ₁ represents the elastic constant, “tilt” deformation at 20°C [pN], K ₂ represents the elastic constant , “Twist” deformation at 20°C [pN], K ₃ represents the elastic constant, “Bend” deformation at 20°C [pN], and LTS represents the low-temperature stability measured by the test unit or the whole as specified ( Nematic phase).

Unless explicitly stated otherwise, the temperature (such as the melting point T(C,N), the transition from the smectic (S) phase to the nematic (N) phase T(S,N) and the clear point T(N , I) or cl.p.) All values indicated are in degrees Celsius (°C). M.p. represents the melting point. In addition, Tg = glassy state, C = crystalline state, N = nematic phase, S = smectic phase and I = isotropic phase. The number between these symbols indicates the transition temperature.

Unless expressly indicated otherwise, the term “threshold voltage” used in the present invention refers to the capacitance threshold (V ₀ ), also known as the Freedericks threshold. In an example, the optical threshold (V ₁₀ ) can also be indicated for 10% relative contrast, as is commonly used.

The display for measuring the threshold voltage of a capacitor consists of two plane parallel glass outer plates with a pitch of 20 µm, each with an electrode layer on the inside and an unrubbed polyimide alignment layer on the top, which realizes liquid crystal The vertical edges of the molecules are aligned.

The display or test unit for measuring tilt angle consists of two plane parallel glass outer plates with a pitch of 4 µm, each with an electrode layer on the inside and a polyimide alignment layer on the top, two of which are polyimide The imine layers rub against each other in antiparallel and realize the vertical edge alignment of liquid crystal molecules.

Unless otherwise indicated, the VHR was measured after 5 minutes in an oven at 20°C (VHR ₂₀ ) and in a commercially available model 6254 instrument from TOYO Corporation in Japan at 100°C (VHR ₁₀₀ ). Unless indicated more precisely, the voltage used has a frequency in the range of 1 Hz to 60 Hz.

The accuracy of the VHR measurement value depends on the individual VHR value. The accuracy decreases as the value decreases. Generally the deviations observed for the values in the various magnitude ranges are compiled in the following table in their order of magnitude.

The stability to UV irradiation was studied in a commercial instrument "Suntest CPS" from Heraeus, Germany. Unless specifically instructed, the sealed test unit is irradiated for 30 minutes to 2.0 hours without additional heating. The irradiation power for wavelengths in the range of 300 nm to 800 nm is 765 W/m ² V. UV "cutoff" filters with an edge wavelength of 310 nm are used in order to simulate the so-called window glass mode. In each series of experiments, at least four test units are studied for each condition, and the individual results are indicated as the average of the corresponding individual measurements.

(1)。The reduction in voltage retention (ΔVHR) usually caused by exposure (for example, by UV irradiation or by LCD backlight) is measured according to the following equation (1):

(1).

In order to study low temperature stability, it is also called "LTS", that is, the stability of the LC mixture in the whole against the spontaneous crystallization or smectic phase of individual components at low temperature, depending on the specific situation, each will contain about 1 g Several sealed bottles of material are stored at one or more given temperatures, usually -10°C, -20°C, -30°C and/or -40°C, and visually inspected at regular intervals for phase changes . Once the first sample shows changes at a given temperature, the time is marked. The time until no change was observed until the last inspection is marked as individual LTS.

The ion density was measured using a commercially available LC material characteristic measurement system model number 6254 from Japan Toyo Corporation, using a VHR test cell with an AL16301 polyimide (Japan JSR Corp.) having a cell gap of 3.2 µm, and the resistivity was calculated based on . Perform the measurement after 5 minutes in an oven stored at 60°C or 100°C.

The so-called "HTP" means the optically active or torsional twisting force (in µm) on the palm material in the LC medium. Unless otherwise indicated, HTP is measured at a temperature of 20° C. with a commercially available nematic LC host mixture MLD-6260 (Merck KgaA).

Unless otherwise specified, all concentrations in this application are indicated in weight percent and refer to the corresponding mixture as a whole (without solvent) containing all solid or liquid crystal components. Unless otherwise specified, all physical properties are measured according to "Merck Liquid Crystals, Physical Properties of Liquid Crystals", Status November 1997, Merck KGaA, Germany, and are suitable for temperatures of 20°C.

The following examples of mixtures with negative dielectric anisotropy are particularly suitable for liquid crystal displays having at least one planar alignment layer, such as IPS and FFS displays, especially UB-FFS (=Ultra Bright FFS), and suitable for VA displays.

Mixture Examples and Comparative Examples Comparative mixture C1 was prepared as follows: (MDA-16-1989)

This mixture has the best possible response time. For the highest achievable VHR value, a medium response time is obtained but a very high VHR value is obtained.

The comparative mixture C2 was prepared as follows:

This mixture has a good balance between VHR and response time.

Mixture M1 was prepared as follows: (MDA-17-372)

Mixture M2 was prepared as follows:

Mixture M3 was prepared as follows:

Mixture M4 was prepared as follows:

The comparative mixture C3 was prepared as follows:

This mixture showed an improved response time compared to Comparative Example 1, mainly due to its reduced gamma ₁ , but showed a lower VHR.

Mixture M5 was prepared as follows:

Mixture M6 was prepared as follows:

Mixture M7 was prepared as follows:

Mixture M8 was prepared as follows:

表1：VHR值

(備註: *所有VHR值在1V、1 Hz下及在60℃下量測。) Mixture M9 was prepared as follows:

Table 1: VHR values

(Remarks: *All VHR values are measured at 1V, 1 Hz and 60°C.)

Claims (15)

A liquid crystal medium, characterized in that it contains: one or more compounds of formula X:

Wherein R ^X1 and R ^X2 each independently represent H, an alkyl group or an alkoxy group having 1 to 15 C atoms, and in addition, one or more of the CH ₂ groups in these groups may be independent of each other -C≡C-, -CF ₂ O-, -OCF ₂ -, -CH=CH-,

,

, -O-, -CO-O-, -O-CO-, so that O atoms are replaced without being directly connected to each other, and in addition, one or more H atoms may be replaced by halogen, n represents 0 or 1, and Z ^X1 represents -CO-O-, -O-CO-, -CF ₂ O-, -OCF ₂ -, -CH ₂ O-, -OCH ₂ -, -CH ₂ -,- CH ₂ CH ₂ -, -(CH ₂ ) ₄ -, -CH=CH-CH ₂ O-, -C ₂ F ₄ -, -CH ₂ CF ₂ -, -CF ₂ CH ₂ -, -CF=CF- , -CH=CF-, -CF=CH-, -CH=CH-, -C≡C- or single bond, and, as the case may be, preferably one or more compounds of formula I:

Wherein R ¹¹ and R ¹² each independently represent H, an alkyl group or an alkoxy group having 1 to 15 C atoms, and in addition, one or more of the CH ₂ groups in these groups may cause O atoms to each other The method of not directly connecting each other independently through -C≡C-, -CF ₂ O-, -OCF ₂ -, -CH=CH-,

,

, -O-, -CO-O-, -O-CO-, and wherein, in addition, one or more H atoms may be replaced by halogen,

Each occurrence independently of one another represents a) 1,4-cyclohexenyl or 1,4-cyclohexyl, where one or two non-adjacent CH ₂ groups can be passed through -O- or -S- Substitution, b) 1,4-phenylene, where one or two CH groups can be replaced by N, c) from piperidine-1,4-diyl, 1,4-bicyclo[2.2.2] octane Group, naphthalene-2,6-diyl, decalin-2,6-diyl, 1,2,3,4-tetrahydronaphthalene-2,6-diyl, phenanthrene-2,7-diyl and A group of stilbene-2,7-diyl group, wherein these groups a), b) and c) may be mono- or poly-substituted with halogen atoms, and Z ¹¹ each independently represents -CO -O-, -O-CO-, -CF ₂ O-, -OCF ₂ -, -CH ₂ O-, -OCH ₂ -, -CH ₂ CH ₂ -, -(CH ₂ ) ₄ -, -CH = CH-CH ₂ O-, -C ₂ F ₄ -, -CH ₂ CF ₂ -, -CF ₂ CH ₂ -, -CF=CF-, -CH=CF-, -CF=CH-, -CH=CH -, -C≡C- or single bond, and L ¹¹ and L ¹² each independently represent F, Cl, CF ₃ or CHF ₂ , X ¹ represents O or S, and a represents 1 or 2, preferably represents 1, and one or more compounds selected from the group of compounds of formulae IIA, IIB and IIC:

Wherein R ^2A , R ^2B and R ^2C each independently represent H, an unsubstituted alkyl or alkenyl group having up to 15 C atoms, mono-substituted by CN or CF ₃ or at least mono-substituted by halogen, wherein, in addition, One or more of the CH ₂ groups in these groups can make O atoms not directly connected to each other via -O-, -S-,

, -C≡C-, -CF ₂ O-, -OCF ₂ -, -OC-O- or -O-CO- substitution, L ¹ to L ⁴ each independently represent F or Cl, Z ² and Z ^{2 '} Each independently represents a single bond, -CH ₂ CH ₂ -, -CH=CH-, -CF ₂ O-, -OCF ₂ -, -CH ₂ O-, -OCH ₂ -, -COO-, -OCO -, -C ₂ F ₄ -, -CF=CF-, -CH=CHCH ₂ O-, p represents 0, 1, or 2, q represents 0 or 1, and v represents 1 to 6. The liquid crystal medium of claim 1, wherein the medium contains one or more compounds selected from the group of compounds of formulae I-1 to I-3:

The parameters have the meanings given in request 1. The liquid crystal medium according to claim 1 or 2, wherein it contains one or more compounds selected from the group of compounds of formulas IO-1 to IO-3:

The parameters have the meanings given in request 1. The liquid crystal medium according to any one of claims 1 to 3, wherein it contains one or more compounds selected from the group of compounds of formulas IS-1 to I-SO-3:

The parameters have the meanings given in request 1. The liquid crystal medium according to any one of claims 1 to 4, wherein it contains one or more compounds of formula IIA:

The parameters have the meanings given in request 1. The liquid crystal medium according to any one of claims 1 to 5, wherein it further comprises one or more compounds of formula IIB:

The parameters have the meanings given in request 1. The liquid crystal medium according to any one of claims 1 to 6, wherein the medium contains one or more compounds of formula IIC:

The parameters have the meanings given in request 1. The liquid crystal medium according to any one of claims 1 to 7, wherein the medium further comprises one or more compounds selected from the group of compounds of formulae O-1 to O-18:

Wherein R ¹ and R ² each independently have the meanings indicated in claim 1 with respect to R ^2A . The liquid crystal medium according to any one of claims 1 to 8, wherein the medium further comprises one or more compounds selected from the group of compounds of formulae T-1 to T-21:

Where R represents a linear alkyl or alkoxy group having 1 to 6 C atoms, and m=0, 1, 2, 3, 4, 5, or 6, and n represents 0, 1, 2, 3, or 4. The liquid crystal medium according to any one of claims 1 to 9, wherein the proportion of the compound of the formula X in the mixture as a whole is 1 to 40% by weight. The liquid crystal medium according to any one of claims 1 to 10, wherein the proportion of the compounds of the formulae IIA to IIC in the medium as a whole is in the range of 10% to 70%. A method for preparing a liquid crystal medium according to any one of claims 1 to 11, characterized in that one or more compounds of formula X and one or more compounds selected from the group of compounds of formulae IIA to IIC are optionally present One or more of the compounds of formula I are mixed. A use of the liquid crystal medium according to any one of claims 1 to 11 in electro-optic displays. An electro-optic display with active matrix addressing, characterized in that it contains a liquid crystal medium as in any one of claims 1 to 11 as a dielectric. The electro-optic display according to claim 15, wherein the electro-optic display is VA, PSA, PA-VA, SS-VA, SA-VA, PS-VA, PALC, IPS, PS-IPS, FFS, UB-FFS, U-IPS Or PS-FFS display.