llIIlIlllIlIlIllIlIllIllIllIIlIlllIlIllIllIIlIIlllllIIllllIIIlllIlllIIlllIIIIIIIIIIIIIIIIIUS 20120307177A1

119) United States112) Patent Application Publication 110) Pub. No. : US 2012/0307177 A1

Manabe et al. 143) Pub. Date: Dec. 6, 2012

175) Inventors:

173) Assignee:

121) Appl. No. :

122) PCT Filed:

186) PCT No. :

Atsutaka Manabe, Bensheim 1JP);Kazuaki Tarumi,Seeheim- Jugenheim 1DE); HubertSpreitzer, Viernheim 1DE); AxelJansen, Darmstadt 1DE); MelanicKlasen-Memmer, Heuchelheim

1DE)

MERCK PATENTGESELLSCHAFT MITBESCHRANKTER HAFTUNG,Darmstadt 1DE)

13/577, 513

Jan. 17, 2011

PC T/EP2011/000172

) 371 1c)11),12), 14) Date: Aug. 7, 2012

130) Foreign Application Priority Data

Feb. 11, 2010 1DE) 102010007539.6

Publication Classification

151) Int. Cl.C09K 19/30C07C 43/225

12006.01)12006.01)

154) LIQUID CRYSTAL DISPLAY AND LIQUIDCRYSTALLINE MEDIUM

C07C 41/30 12006.01)G02F 1/13357 12006.01)

152) U.S. Cl. ....................... 349/61; 252/299. 63; 568/647

157) ABSTRACT

The invention relates to an electro-optical liquid-crystal dis-

play which contains, as dielectric, a liquid-crystallinemedium having negative dielectric anisotropy and includes abacklight which essentially only emits light having a wave-Iengh of 400 nm or more or has, between the liquid-crystallayer and the backlight, a cut-off filter which essentially onlyallows light having a wavelength of 420 nm or more to passthrough.

In particular, the liquid-crystalline medium comprisesa) a 1first) dielectrically negative component 1component A)

which consists of one or more dielectrically negative com-pounds of the formula I

F F

R" A" Z" Au Z'Pl /

Z" A" R"ll

in which the parameters have the meanings indicated in claim2, and a further 1second) dielectrically negative component1component B).Very particular preference is given to the useof the liquid-crystalline media in an electro-optical display,particularly in an active-matrix display based on the VA,ECB, PSVA, FFS or IPS effect and very particularly in dis-plays which use an LED backlight.

US 2012/0307177 A1 Dec. 6, 2012

LIQUID CRYSTAL DISPLAY AND LIQUIDCRYSTALLINE MEDIUM

[0001] The present invention relates to liquid-crystal dis-

plays, particularly liquid-crystal displays which use the ECB(electrically controlled birefringence) effect with dielectri-cally negative liquid crystals in a homeotropic initial align-ment, and to the liquid-crystal media used in these liquid-crystal displays. The liquid-crystal displays according to theinvention are, in particular, liquid-crystal displays which usean LED backlight or those which use a cut-off filter betweenthe backlight and the liquid-crystal cell. The liquid-crystaldisplays according to the invention are distinguished by along lifetime and high reliability at the same time as a par-ticularly short response time and at the same time a highvoltage holding ratio (VHR or HR for short).

[0002] Displays which use the ECB effect have becomeestablished as so-called VAN (vertically aligned nematic)displays, besides IPS (in-plane switching) displays (forexample: Yeo, S. D., Paper 153:"An LC Display for the TVApplication", SID 2004 International Symposium, Digest ofTechnical Papers, XXXV, Book II, pp. 758 & 759) and thelong-known TN (twisted nematic) displays, as one of thethree more recent types of liquid-crystal display that are cur-rently the most important, in particular for television appli-cations.

[0003] The most important designs that should be men-tioned are: MVA (multidomain vertical alignment, forexample: Yoshide, H. et al. , Paper 3.1:"MVA LCD for Note-book or Mobile PCs. . . ", SID 2004 International Sympo-sium, Digest of Technical Papers, XXXV, Book I, pp. 6 to 9,and Liu, C. T. et al. , Paper 15.1:"A 46-inch TFT-LCD HDTVTechnology. . .",SID 2004 International Symposium, Digestof Technical Papers, XXXV, Book II, pp. 750 to 753), PVA(patterned vertical alignment, 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 Techni-cal Papers, XXXV, Book II, pp. 760 to 763),ASV (advancedsuper view, for example: Shigeta, Mitzuhiro and Fukuoka,Hirofumi, Paper 15.2: "Development of High QualityLCDTV", SID 2004 International Symposium, Digest ofTechnical Papers, XXXV, Book II, pp. 754 to 757), and PSVA(polymer-stabilised vertical alignment or polymer-sustainedvertical alignment).

[0004] In general form, the technologies are compared, forexample, in Souk, Jun, SID Seminar 2004, Seminar M-6:"Recent Advances in LCD Technology", Seminar LectureNotes, M-6/I to M-6/26, and Miller, Ian, SID Seminar 2004,Seminar M-7: "LCD-Television", Seminar Lecture Notes,M-7/I to M-7/32. Although the response times of modernECB displays have already been significantly improved byaddressing methods with overdrive, for example: Kim,Hyeon Kyeong et al. , Paper 9.1: "A 57-in. Wide UXGATFT-LCD for HDTV Application", SID 2004 InternationalSymposium, Digest of Technical Papers, XXXV, Book I, pp.106 to 109, the achievement of video-compatible responsetimes, in particular in the switching of grey shades, is still aproblem which has not yet been solved to a satisfactoryextent.

[0005] ECB or VA displays, like ASV displays, use liquid-crystalline media having negative dielectric anisotropy (AE),whereas TN and to date all conventional IPS displays useliquid-crystalline media having positive dielectric anisotropy.

[0006] In liquid-crystal displays of this type, the liquidcrystals are used as dielectrics, whose optical propertieschange reversibly on application of an electrical voltage.[0007] Since in displays in general, i.e. also in displays inaccordance with these mentioned effects, the operating volt-age should be as low as possible, use is made of liquid-crystalmedia which are generally predominantly composed of liq-uid-crystal compounds, all ofwhich have the same sign of thedielectric anisotropy and have the highest possible value ofthe dielectric anisotropy.[0008] In the media used in accordance with the presentapplication, at most significant amounts of dielectrically neu-tral liquid-crystal compounds and generally only very smallamounts of dielectrically positive compounds or even none atall are typically employed, since in general the liquid-crystaldisplays are intended to have the lowest possible addressingvoltages.[0009] The addressing voltage of the displays of the priorart is often too great, in particular for displays which are notconnected directly or not continuously to the power supplynetwork, such as, for example, displays for mobile applica-tions.[0010] In addition, the phase range must be sufficientlybroad for the intended application.

[0011] In particular, the response times of the liquid-crystalmedia in the displays must be improved, i.e. reduced. This isparticularly important for displays for television or multime-dia applications. In order to improve the response times, it hasrepeatedly been proposed in the past to optimise the rotationalviscosity ofthe liquid-crystal media (7,), i.e. to achieve mediahaving the lowest possible rotational viscosity. However, theresults achieved here are inadequate for many applicationsand therefore make it appear desirable to find further optimi-sation approaches.

[0012] The majority of LCDs produced today use a back-light, for example virtually all computer screens and televi-sions. The most widespread type of backlight at present arecold cathode fluorescent lamps (CCFLs for short, also calledcold cathode light tubes). However, the radiation from thesebacklights contains a non-negligible proportion of short-wave light, for example in the range ofwavelengths of380nmand below. Depending on the display substrate used, or itsspectral light transparency, a not inconsiderable proportion ofthis relatively short-wave light, and possibly even in the nearUV, reaches the liquid crystal. Since most liquid-crystalmaterials have only finite stability to UV radiation, and insome cases also to short-wave, visible light, this results in alimited lifetime of the displays. Also for this reason, it hasalready been proposed in the literature to use backlightingwhose light source(s) is (are) light-emitting diodes (LEDs forshort). A further advantage of the use ofLED backlights is thebroadening that can be achieved therewith of the colour spacewhich can be displayed and/or the contrast. The latter effect isparticularly pronounced on use ofdivided, separately addres-sable LED backlights.

[0013] There is therefore a great demand for liquid-crystaldisplays and corresponding liquid-crystal media which do nothave the disadvantages ofthe displays or media from the priorart, or at least do so to a significantly reduced extent.

[0014] Surprisingly, it has been found that it is possible toachieve liquid-crystal displays which have a short responsetime in ECB or VA displays and at the same time have asufficiently broad nematic phase, favourable birefringence(An) and a high voltage holding ratio.

US 2012/0307177 A1 Dec. 6, 2012

[0015] Media of this type are to be used, in particular, forelectro-optical displays with active-matrix addressing basedon the ECB or VA effect and for IPS or FFS (fringe fieldswitching) displays. The medium according to the inventionpreferably has negative dielectric anisotropy.

[0016] The principle of electrically controlled birefrin-gence, the ECB (electrically controlled birefringence) effector DAP (deformation ofaligned phases) effect, was describedfor the first time in 1971 (M. F. Schieckel and K. Fahrenschon,"Deformation of nematic liquid crystals with vertical orien-tation in electrical fields", Appl. Phys. Lett. 19 (1971),3912).Papers by J. F. Kahn (Appl. Phys. Lett. 20 (1972), 1193)andG. Labrunie and J. Robert (J. Appl. Phys. 44 (1973), 4869)followed.

[0017] The papers by J.Robert and F. Clerc (SID 80 DigestTechn. Papers (1980),30), J. Duchene (Displays 7 (1986),3)and H. Schad (SID 82 Digest Techn. Papers (1982),244) haveshown that liquid-crystalline phases must have high valuesfor the ratio between the elastic constants Ka/K„high valuesfor the optical anisotropy An and values for the dielectricanisotropy AE of ~—0.5 in order to be suitable for use forhigh-information display elements based on the ECB effect.Electro-optical display elements based on the ECB effecthave a homeotropic edge alignment (VAtechnology~ertically aligned). Dielectrically negative liq-uid-crystal media can also be used in displays which use theIPS or FFS effect.

[0018] Industrial application ofthis effect in electro-opticaldisplay elements requires liquid-crystalline media whichhave to meet a multiplicity of requirements. Particularlyimportant here are chemical resistance to moisture, air andphysical influences, such as heat, radiation in the infrared,visible and ultraviolet regions, and direct and alternating elec-tric fields.

[0019] Furthermore, liquid-crystalline media which can beused industrially are required to have a liquid-crystallinemesophase in a suitable temperature range and low viscosity.

[0020] None of the series of compounds having a liquid-crystalline mesophase that have been disclosed hithertoincludes a single compound which meets all these require-ments. Mixtures of two to 25, preferably three to 18, com-pounds are therefore generally prepared in order to obtainsubstances which can be used as liquid-crystalline media.

[0021] Matrix liquid-crystal displays (MLC displays) areknown. Non-linear elements which can be used for individualswitching of the individual pixels are, for example, activeelements (ke. transistors). The term "active matrix" is thenused, where in general use is made of thin-film transistors(TFTs), which are generally arranged on a glass plate assubstrate.

[0022] A distinction is made between two technologies:TFTs comprising compound semiconductors, such as, forexample, CdSe, or TFTs based on polycrystalline and, interalia, amorphous silicon. The latter technology currently hasthe greatest commercial importance worldwide.

[0023] The TFT matrix is applied to the inside of one glassplate of the display, while the other glass plate carries thetransparent counterelectrode on its inside. Compared with thesize of the pixel electrode, the TFT is very small and hasvirtually no adverse effect on the image. This technology canalso be extended to fully colour-capable displays, in which amosaic of red, green and blue filters is arranged in such a waythat a filter element is opposite each switchable pixel.[0024] The term MLC displays here covers any matrix dis-play with integrated non-linear elements, i.e. besides theactive matrix also displays with passive elements, such asvaristors or diodes (MIM=metal-insulator-metal).[0025] MLC displays of this type are particularly suitablefor TV applications, monitors and notebooks or for displayswith a high information density, for example in automobilemanufacture or aircraft construction. Besides problemsregarding the angle dependence of the contrast and theresponse times, difficulties also arise in MLC displays due toinsufficiently high specific resistance of the liquid-crystalmixtures [TOGASHI, S., SEKIGUCHI, K., TANABE, H. ,YAMAMOTO, E., SORIMACHI, K., TAJIMA, E.,WATANABE, H. , SHIMIZU, H. , Proc. Eurodisplay 84, Sep-tember 1984:A 210-288 Matrix LCD Controlled by DoubleStage Diode Rings, pp. 141 ff., Paris; STROMER, M. , Proc.Eurodisplay 84, September 1984: Design of Thin Film Tran-sistors for Matrix Addressing of Television Liquid CrystalDisplays, pp. 145 ff., Paris]. With decreasing resistance, thecontrast of an MLC display deteriorates. Since the specificresistance of the liquid-crystal mixture generally drops overthe life ofan MLC display owing to interaction with the insidesurfaces of the display, a high (initial) resistance is veryimportant for displays that have to have acceptable resistancevalues over a long operating period.[0026] 1,2-Difluoroethylene-bridged biphenyls (alsocalled trans-1, 2-difluorostilbenes), and corresponding ter-phenyls, each of which may also carry one F atom or two Fatoms in the 2,3-position on the I -phenylene units present, arementioned in Goodby, J. W. , Hindmarsh, P. , Hird, M. , Lewis,R. A. , and Toyne, K. J., Mol. Cryst. and Liq. Cryst. , 2001Volume 364, pages 889-898. However, the only representa-tives of the compounds presented are those containing rela-tively long alkyl or alkoxy end groups, which very predomi-nantly have smectic phases.[0027] In EP 0 560 382, alkoxy compounds having a 1,2-difluoroethylene bridge, inter alia, are disclosed and pro-posed, in particular, for use in liquid crystals for STN dis-plays.[0028] DE 101 55 073 discloses 1,2-difluoroethylene-bridged biphenyls (also called difluorostilbenes).[0029] Dielectrically positive stilbene compounds havingone F atom or having two F atoms on the ethylene bridge aredisclosed in EP I 215 270, and dielectrically neutral or posi-tive stilbene compounds having two F atoms on the ethylenebridge are disclosed in WO 2006/133 783 and used in dielec-trically positive liquid-crystal mixtures.[0030] In EP I 932 896, compounds having a 1,2-difluoro-ethylene bridge of the general formula

gl 1 Al l Z 1 1 /F F F

US 2012/0307177 A13

Dec. 6, 2012

and illustrative representatives, are mentioned and proposedas constituents of liquid-crystal mixtures for, for example,VAN LCDs.[0031] In DE 10 2008 035 890, compounds having a 1,2-ethynylene bridge on a saturated six-atom ring of the generalformula

[0039] in which[0040] R» and R' each, independently of one another,

denote H, an unsubstituted alkyl or alkenyl radical havingup to 15 C atoms, where, in addition, one or more CH~groups in these radicals may be replaced by ~, S

F F

R11 A 0"and illustrative compounds of this formula, are mentionedand used as constituents in liquid-crystal mixtures havingnegative dielectric anisotropy.[0032] The disadvantage of the MLC displays known todate is based on their comparatively low stability to UVradiation, light and/or heat, which limits the lifetime and isinadequate for some applications. These displays often havean inadequate voltage holding ratio and an inadequate life-time.[0033] Thus, there continues to be a great demand for MLCdisplays having very high specific resistance at the same timeas a large working-temperature range, short response timesand a low threshold voltage with the aid ofwhich various greyshades can be produced and which have, in particular, a goodand stable voltage holding ratio and a long lifetime.

[0034] Surprisingly, it has now been found that this objectcan be achieved if nematic liquid-crystal mixtures whichcomprise at least one compound of the formula I and at leastone further, mesogenic compound are used in these displayelements, in particular if the display elements have an LEDbacklight and/or a cut-off filter which prevent short-waveradiation (radiation in the near-UV region or short-wave bluelight) from reaching the liquid-crystal medium.

[0035] In particular, a high VHR, high stability and reliabil-ity and short response times are desired here.

[0036] The mixtures according to the invention exhibit verybroad nematic phase ranges with clearing points )85' C.,very favourable values for the capacitive threshold, relativelyhigh values for the holding ratio and at the same time verygood low-temperature stabilities at —30' C. and —40' C. aswell as very low rotational viscosities. The mixtures accord-ing to the invention are furthermore distinguished by a goodratio of clearing point and rotational viscosity and by highnegative dielectric anisotropy.

[0037] The invention relates to a liquid-crystal displaywhich contains a dielectrically negative, nematic mediumwhich comprises

[0038] a) a first dielectrically negative component (compo-nent A), which consists of one or more compounds of theformula I

A 12

and, if present,

A11 A"

each, independently of one another, denote

c3-

/ i /

C, MF~M, MMF~, MO 0 orCO in such a way that 0 atoms are not linked

directly to one another, preferably an unsubstituted alkyl,alkenyl, alkoxy, oxaalkyl or alkenyloxy radical, particularlypreferably one of R» and R' denotes an alkyl or alkenylradical and the other denotes an alkyl, alkenyl, alkoxy oralkenyloxy radical, particularly preferably R» denotesstraight-chain alkyl, alkenyl or alkoxy, in particular CH3O~H, n-C H, n-C H orn-C H» (orC~H 0and R' denotes straight-chain alkyl, alkenyl or alkoxy, inparticular C~H5~ or n-C4H9~

F F

R" A" Z" A'~ Z'Pl /

Z" A" R"ll

F F

US 2012/0307177 A1 Dec. 6, 2012

preferably in which[0046] R ' and R each, independently of one another,

denote H, an unsubstituted alkyl or alkenyl radical having

up to 15 C atoms, where, in addition, one or more CH2groups in these radicals may be replaced by ~, S

F F

particularly preferably

[0041] Z' denotes MF CF, MF CHMH CF, MH CH or M C, preferablyMF CF, CH CH or M C and particu-larly preferably ~F CF or CH CH

[0042] Z" and Z', if present, each, independently of oneanother, denote CH2 CH2, ~H CH

C, CH2 0, M CH2, MOMMMO, MF2M, OMF2, MF2CF2 or a single bond, preferably a single bond,

[0043] m and n, independently of one another, denote 0, Ior 2, preferably m denotes 0, I or 2 and n denotes 0 or I,particularly preferably 0, and very particularly preferablym and n both denote 0, and

[0044] (m+n) preferably denotes 0, I or 2, particularly pref-erably 0 or I and very particularly preferably 0

[0045] b) optionally, preferably obligatorily, a seconddielectrically negative component (component B), whichconsists of one or more compounds selected from thegroup of the formulae II, III and IV:

C, MF2M, MMF2, MO 0 orCO in such a way that 0 atoms are not linked

directly to one another, preferably an unsubstituted alkyl,alkenyl, alkoxy or alkenyloxy radical, particularly preferablyone ofR ' and R denotes an alkyl or alkenyl radical and theother denotes an alkyl, alkenyl, alkoxy or alkenyloxy radical,preferably, independently of one another, alkyl having I to 7C atoms, preferably n-alkyl, particularly preferably n-alkylhaving I to 5 C atoms, alkoxy having I to 7 C atoms, prefer-ably n-alkoxy, particularly preferably n-alkoxy having I to 5C atoms, or alkoxyalkyl, alkenyl or alkenyloxy having 2 to 7C atoms, preferably having 2 to 4 C atoms, preferably alkenyl,where in all groups one or more H atoms may be replaced byhalogen atoms, preferably F atoms, particularly preferablyone of R ' and R, preferably R ', denotes an alkyl or alk-

enyl radical and the other denotes an alkyl, alkenyl, alkoxy oralkenyloxy radical, particularly preferably R ' denotesstraight-chain alkyl, in particular CH3, C2Hs, n-C3H7n-C4H9 or n-CsH», or alkenyl, in particularCH, CH, E-CH, MH CH, CH, CHMH,CH2, E-CH3 CH CH CH2~H2 or E-n-C3H7CH CH[0047] R ', R, R ' and R each, independently of one

another, have one of the meanings given for R ' and Rand preferably denote alkyl having I to 7 C atoms, prefer-ably n-alkyl and particularly preferably n-alkyl having I to5 C atoms, alkoxy having I to 7 C atoms, preferablyn-alkoxy and particularly preferably n-alkoxy having 2 to 5C atoms, or alkoxyalkyl, alkenyl or alkenyloxy having 2 to7 C atoms, preferably having 2 to 4 C atoms, preferablyalkenyloxy, particularly preferably one of R ' and R

R21 A21 Z21 A22 Z22 A23 Z23 A24 R22r 5

III

R' A' Z' A Z A Z A Ri 0

IV

R' A' Z' A Z A Z A RI II

US 2012/0307177 A1 Dec. 6, 2012

preferably R ', denotes an alkyl or alkenyl radical and theother denotes an alkyl, alkenyl, alkoxy or alkenyloxy radi-cal, particularly preferably R ' denotes straight-chainalkyl, in particular CH2, C2Hs, n-C2H2, n-C4H9or n-CsH», or alkenyl, in particular CH2 CHE CH2 CH CH CH2 CH~H2 CH2E-CH2 CH CH CH2~H2 or E-n-C2H2CH CH

one of the rings

preferably

A21 to A24

present denotes

particularly preferably

[004S] L ' and L, independently of one another, denoteC(X ) and one of L and L alternatively also

denotes N, where preferably at least one of L ' andL denotes C( F) and the other denotes C(F) or C(~1),particularly preferably L ' and Lboth denote C( F)

[0049] X denotes F, Cl, OCF2, CF2, CH2, CH2F, CHF2,preferably F or Cl, particularly preferably F,

and the other rings, if present, each, independently of oneanother, denote

preferably denotes

F F

F Ct

Ct F

particularly preferably

F F

one of the rings

A" to A'4

present denotes

/F

F F

US 2012/0307177 A1 Dec. 6, 2012

FF F

FF F

-continuedwhere

[0050] L ' and L, independently of one another, denoteC(X ) and one of L ' and L alternatively also

denotes N, where pref erably at least one of L ' andL denotes C( F) and the other denotes C(F) or C( Cl), particularly preferably L ' and Lboth denote C( F), and

[0051] X denotes F, Cl, OCF3, CF3, CH3, CH2F, CHF2,preferably F or Cl, particularly preferably F,

preferably

FF F

A'4/ X /

F F

preferably denotes

FF F

For

FF F

particularly preferably

A'4

and the others, ifpresent, each, independently ofone another,

denotedenotes

F F

/ A"

denotes

together optionally also denote a single bond, where, in thecase where

L31 L32

/ A'4

US 2012/0307177 A1 Dec. 6, 2012

denotes

FF F

For

FF F

-continuedF F

then

[0052] R preferably denotes H,

one of the rings

F F

/

A41 A44

present denotes and the others, ifpresent, each, independently ofone another,denote

F F F F

//

F F

//

F F

F F

/

F F&'3—

/ i /

F F

/ i // i /

F F

preferably

/ i /0 F

/ i /

US 2012/0307177 A1 Dec. 6, 2012

F F-continued

each, independently of one another, denote

together optionally also denote a single bond,

[0053] Z ' to Z

[0054] Z 'to Z and

[0055] Z ' to Z each, independently of one another, haveone of the meanings given for Z" under formula I andpreferably denote MHs MCH2, MHs MOMH CH, M C, MOO or a single bond,preferably MHsMCH2, CH2 0 or a single bondand particularly preferably ~Hs~O or a single bond,

[0056] Z ' to Z preferably each, independently of oneanother, denote CH2 CH2, MHs MCF2MF2 CH2 ) CFsMCF2 ) MH CHMF CH, MH CF, M C, MHsMO~~H2, CO~, ~ CO, CFs~OMMF2 or a single bond, preferably MH2CH2 ) MH CH M C CFsMO~~F2 or a single bond, particularly preferably oneor, ifpresent, in each case a plurality of Z ' to Z, orZ 'to Z, or Z ' to Z denote a single bond, and very par-ticularly preferably all denote a single bond,

r and s each, independently of one another, denote 0 or 1,(r+s) preferably denotes 0 or 1,t and u each, independently of one another, denote 0 or 1,

(t+u) preferably denotes 0 or 1, preferably 0,1 and o each, independently ofone another, denote 0 or 1, and

(1+o) preferably denotes 0 or 1,and optionally

[0057] c) a dielectrically neutral component (componentC), which consists of one or more compounds of the for-mula V

/ i /

preferably

Rst As& Zst As2 Zs2 Ass Zss As4 Rs2P

in which

[005S] R ' and R each, independently of one another,have one of the meanings given for R" and R' and pref-erably denote alkyl having 1 to 7 C atoms, preferablyn-alkyl, particularly preferably n-alkyl having 1 to 5 Catoms, alkoxy having 1 to 7 C atoms, preferably n-alkoxy,particularly preferably n-alkoxy having 2 to 5 C atoms,alkoxyalkyl, alkenyl or alkenyloxy having 2 to 7 C atoms,preferably having 2 to 4 C atoms, preferably alkenyloxy,

A"

preferably denotes

A" to A'4 A'4

US 2012/0307177 A1 Dec. 6, 2012

preferably denotes

and, if present,

As2

preferably denotes

[0059] Z ' to Z each, independently of one another, haveone of the meanings given for Z" under formula I andpreferably denote MHsMCH2, MH CH

C, MOO or a single bond, preferably~H2 CH2 or a single bond and particularly prefer-ably a single bond,

p and q each, independently of one another, denote 0 or I,(p+q) preferably denotes 0 or I, preferably 0, and optionally

d) a chiral component (component D), which consists of oneor more chiral compounds.

[0060] In addition, the invention relates to novel liquid-crystal media of the composition specified above for theliquid-crystal displays.

[0061] The media according to the invention, or the mediaemployed in the displays according to the invention, are pref-erably dielectrically negative.[0062] The media according to the invention, or the mediaemployed in the displays according to the invention, prefer-ably comprise one, two, three, four or more, preferably two orthree or more, compounds of the formula I.[0063] Particular preference is given to compounds of theformula I in which[0064] a) R" and/or R' denote H, alkyl, alkenyl, alkoxy,

oxaalkyl or alkenyloxy, preferably having up to 6 C atoms,R" very particularly preferably denotes alkoxy or alkeny-loxy, and R' very particularly preferably denotes alkyl oroxaalkyl, or

[0065] b) R" and R' both denote alkyl, where the alkylradicals may be identical or different, or

[0066] c) R" denotes straight-chain alkoxy and R'denotes straight-chain alkyl or oxaalkyl.

[0067] If R" and/or R' denote alkenyl, this is preferablyCH, CH, CH, CH CH, CH, CH~, H4 orCH, CH CH C,H4[006S] IfR" and/or R' denote oxaalkyl, this is preferablyCHs OMH2 ) CHs [3 C2H4 ) C2HsMH CHCH, , C,H, CH CHM, H or CH, OM, H,preferably CHs OMH2, CHs OM2H4 or CHsOM, Hs and particularly preferably CHs OMH2[0069] If R" and/or R' denote alkyl, this is preferablymethyl, ethyl, n-propyl, nbutyl or n-pentyl, preferablymethyl, ethyl, n-propyl or n-pentyl and particularly prefer-ably ethyl or n-propyl.[0070] If R" and/or R' denote alkoxy, this is preferablymethoxy, ethoxy or n-butoxy, preferably ethoxy or n-butoxy.[0071] The compounds of the formula I are preferablyselected from the group ofthe compounds of the formulae I- Ito I-5, preferably from the group of the formulae I-l, 1-2, 1-4and I-5, particularly preferably of the formulae I-l and/or 1-4and/or I-5:

Rl 1 Al 1 Z 1 1 A12

F F F

/Z" A" R"

Rl 1 Al 1 Z 1 1 A12

F FI-2

R" A" Z" A12

F F F

Z" A" R"/ n

I-3

Rl 1 Al 1 Z 1 1

F F

A

Z" A" R"/ n

US 2012/0307177 A110

Dec. 6, 2012

-continued

F F1-5

R«A11 Z A12 C=C~ /

Z A R

R11

F F F

I- Ib

R11

F F F

R12

I-I c

R11

F F

in which the parameters have the respective meanings givenabove under formula I.[0072] The compounds of the formula I-l are particularlypreferably selected from the group of the compounds of theformulae I-la to I-lg, preferably from the group of the for-mulae I-la, I-lb, I-lc, I-le and I-l f, particularly preferably ofthe formulae I-la, I-lb and/or I-Ic and/or I-l d, very particu-larly preferably of the formulae I-la and/or I-Ib:

[0074] R' denotes alkyl, alkenyl or alkoxy, particularlypreferably alkoxy,

in the case of formula I-Id[0075] R" denotes alkyl, alkenyl or alkoxy, particularly

preferably alkyl or alkoxy, and[0076] R' denotes alkyl, alkenyl or alkoxy, particularly

preferably alkoxy,in the case of formula I-le[0077] R" denotes alkyl, alkenyl or oxaalkyl, particularly

preferably alkyl or alkenyl, very particularly preferablyalkyl, and

[007S] R' denotes alkyl, alkenyl or alkoxy, particularlypreferably alkyl or alkoxy.

[0079] In the case of the compounds of the formulae I-la,I-lb, I-l c, I-ld, I-le and I-l g, particular preference is given tothe compounds in which R" denotes alkyl or alkenyl and R'denotes alkoxy or R" and R' denote alkoxy.[00SO] In the case of the compounds of the formula I-lb,particular preference is given to the compounds in which R"denotes alkyl or alkenyl and R' denotes alkoxy or R" andR' denote alkyl.[00S1] The compounds of the formula I-2 are particularlypreferably selected from the group of the compounds of theformulae I-2a to I-2d, preferably from the group of the for-mulae I-2a and I-2b, particularly preferably of the formulaI-2a:

R11

/

/

R12

F F

I-I e

R12

R11

R11

F F

F F

I-2a

I-2b

/ X /F F

/ X /

/

in which the parameters have the respective meanings givenabove under formula I and preferably in the case of formulaeI-la, I-lb, I-lc, I-If and I-lg[0073] R" denotes alkyl, alkenyl or oxaalkyl, particularly

preferably alkyl or alkenyl, very particularly preferablyalkyl, and

R11

R11

F F

F F

R12

I-2d

R12

in which the parameters have the respective meanings givenabove under formula I and preferably in the case of formulaI-2b

US 2012/0307177 A1 Dec. 6, 2012

I-3b

Rl 1

F F F

Rl 1

F F F

/R12

I-3d

Rl 1

F F

R12

[00S2] R" denotes alkyl, alkenyl or alkoxy, particularlypreferably alkyl, and

[00S3] R' denotes alkyl, alkenyl or alkoxy, particularlypreferably alkoxy.

[00S4] The compounds of the formula 1-3 are particularlypreferably selected from the group of the compounds of theformulae I-3a to 1-3d, preferably from the group of the for-mulae I-3a and I-3b, particularly preferably of the formulaI-3a:

I-3aF F F

Rl 1

-continuedI-4d

Rl 1

F F

/R12

in which the parameters have the respective meanings givenabove under formula I and preferably in the case of formulaeI-4a and I-4b

[00SS] R" denoted alkyl or alkenyl, particularly preferablyalkyl, and

[00S9] R' denotes alkyl or alkoxy, particularly preferablyalkoxy.

[0090] In the case of the compounds of the formula I-4a,particular preference is given to the compounds in which R"denotes alkyl and R' denotes alkoxy or R" denotes alkenyland R' denotes alkoxy and very particularly the combinationin which R" denotes alkyl and R' denotes alkoxy.

[0091] In the case of the compounds of the formula I-4b,particular preference is given to the compounds in which R"denotes alkyl and R' denotes alkyl or R" denotes alkyl oralkenyl and R' denotes alkoxy and very particularly thecombination in which R" denotes alkyl and R' denotesalkoxy.

[0092] The compounds of the formula I-5 are particularlypreferably selected from the group of the compounds of theformulae I-Sa to I-Se:

in which the parameters have the respective meanings givenabove under formula I and preferablyin the case of formula I-3b

[00S5] R" denotes alkyl, alkenyl or alkoxy, particularlypreferably alkyl, and

[00S6] R' denotes alkyl, alkenyl or alkoxy, particularlypreferably alkoxy.

[00S7] The compounds of the formula 1-4 are particularlypreferably selected from the group of the compounds of theformulae I-4-a to I-4d, preferably from the group of the for-mulae I-4a and I-4b, particularly preferably of the formulaI-4a:

Rl 1

F FI-Se

I-5b

F F

C—

C

~ /R12

I-5c

R" C=Cy /

R'2

Rl 1

F F

F F

Rii C—:C /

Rl 1

F F

I-4b

R" C=C

F F F

Rl 1

F F

/R12

R"y / C=C

I-5eF F

US 2012/0307177 A112

Dec. 6, 2012

in which the parameters have the respective meanings givenabove under formula I and preferably

in the case of the formulae I-Sa and I-Sb

[0093] R" denotes alkyl or alkenyl, particularly preferablyalkyl, and

[0094] R' denotes alkyl, alkenyl or alkoxy, particularlypreferably alkoxy, and

in the case of the formulae I-Sc and I-Sd

[0095] R" denotes alkyl or alkenyl and

[0096] R' denotes alkyl, alkenyl oralkoxy.

[0097] In the case of the compounds of the formula 1-5a,particular preference is given to the compounds in which R"denotes alkyl and R' denotes alkyl, R" denotes alkyl andR denotes alkoxy or R denotes alkenyl and R denotesalkoxy and very particularly the combination in which R"denotes alkyl and R' denotes alkoxy.

[009S] In the case of the compounds of the formula 1-5b,particular preference is given to the compounds in which R"denotes alkyl and R' denotes alkyl, R" denotes alkyl andR denotes alkoxy, R denotes alkenyl and R denotesalkoxy or R" denotes alkenyl and R' denotes alkyl and veryparticularly the combination in which R" denotes alkyl andR' denotes alkoxy.

[0099] In the case of the compounds of the formula 1-5c,particular preference is given to the compounds in which R"denotes alkyl and R' denotes alkyl or alkenyl.

[0100] In the case of the compounds of the formula 1-5d,particular preference is given to the compounds in which R"denotes alkyl and R' denotes alkyl or alkoxy.

[0101] In a preferred embodiment, the medium comprisesone or more compounds of the formula II, selected from thegroup of the compounds of the formulae IIA to IID, prefer-ably IIA to IIC and very particularly preferably IIA and IIB:

A22

[0102] does not denote

and does not denote

and preferably

A21

independently of one another, denote

A22

X21 X22

and particularly preferably

A2& Z2& A22 z» / X R»r

A21

X21 X22

denotes

R21 A21 Z21 i Z22 / i R22

IIC

X21 X22

A» Z» / ~ Z22

IID

A2 & Z2 & A22 Z22 A22 Z22 A24

in which the parameters have the respective meanings indi-cated above, but in formula IIA, in the case where r=l,

[0103] R ' denotes alkyl,

[0104] R denotes alkyl or alkoxy, particularly preferably

(O)C,H2, „[0105] X ' and X both denote F,

[0106] Z ' and Z, independently of one another, denote asingle bond, CH2 CH2, CH CH, CH20

OCH2, 0,MH2, MF20 or OCF2preferably a single bond or ~H2CH2, particularlypreferably a single bond,

[0107] p denotes I or 2, and

[010S] v denotes I to 6.

US 2012/0307177 A113

Dec. 6, 2012

[0109] In a preferred embodiment, the medium comprisesone or more compounds of the formula II, selected from the

group of the compounds of the formulae II-I to II-16:-continued

V24 F F

11-12

R21

R21

F F

/

F F

/

11-2

11-3

/X /X /X /

V24 V2~ V24 F F

/X /X /X /

11-13

11-14

/ X / R21

R21

R21

F F

/F F

/

11-4

R21

R21

F F

/ X /

11-16

R21

R21

R21

/ X /

F F

/F F

/ X /

F F

F F

/ X /

F F Z22 Z24

/4 /X /

11-6

11-7

11-8

11-9

R22

11-10

in which

[0110] Y ' to Y, independently of one another, denote Hor F, and

[0111] X" and X"both denote H or one of X" and X"denotes H and the other denotes F,

but preferably at most four, particularly preferably at mostthree and very particularly preferably one or two ofY ' to YX"and X"denote F,and

the other parameters have the respective meanings indicatedabove for formula II and preferably

[0112] R ' denotes alkyl or alkenyl and

[0113] R denotes alkyl, alkenyl, alkoxy or alkenyloxy,preferably (O)C,H2, „and

[0114] v denotes an integer from I to 6.[0115] R preferably denotes straight-chain alkyl or alkoxy,each having I to 6 C atoms, or alkoxyalkyl, alkenyl or alk-enyloxy having 2-6 C atoms, particularly preferably alkylhaving 1-5 C atoms, preferably methyl, ethyl, propyl, butyl,or furthermore alkoxy having 1-5 C atoms, preferably hexyl,methoxy, ethoxy, propoxy or butoxy.

[0116] The medium preferably comprises one or morecompounds of the formula III, selected from the group of thecompounds of the formulae III-I and preferably of the for-mula III-2:

R21

F F

/ X / X / X R22 R" Z" Z" „

F FF

(Fion

R

US 2012/0307177 A114

Dec. 6, 2012

-continued

R» z» z32r

111-2

F FF

(Fion

-continued

F F

R41 z42 / i p

R42

IV-7

F F

/

IV-I

R41 Z41

IV-I

F F

/

in which the parameters have the respective meanings indi-cated above for formula III and preferably[0117] R ' denotes alkyl or alkenyl,[011S] R denotes alkyl, alkenyl, alkoxy or alkenyloxy,[0119] Z ' denotes a single bond and[0120] r denotes 0.[0121] In a further preferred embodiment, the medium (ad-ditionally) comprises one or more compounds of the formulaIV, preferably selected from the group of the compounds ofthe formulae IV-I to IV-8, preferably of the formulae IV-7and/or IV-8:

IV-8

R41

F F

... /R42

in which the parameters have the respective meanings indi-cated above for formula IV and preferably[0122] R ' denotes alkyl or alkenyl and[0123] R denotes alkyl, alkenyl, alkoxy oralkenyloxy.[0124] In this embodiment, preferably if the medium com-prises one or more compounds of the formulae IV-7 and/orIV-8, the medium can essentially consist ofcompounds of theformulae I, II, IV and V.[0125] In a further preferred embodiment, the medium (ad-ditionally) comprises one or more compounds which containa

fluorinated

phenanthren unit, preferably compounds of theformula IV, preferably selected from the group of the com-pounds of the formulae IV-9 and IV-10:

R" z42

F FIV-3

F FIV-9

/R41 Z41 /

IV-10

IV-4

F F

F F F

R41

F F

/R" Z"

IV-5

in which the parameters have the respective meanings indi-cated above for formula IV and preferably[0126] R ' denotes alkyl or alkenyl and[0127] R denotes alkyl, alkenyl, alkoxy oralkenyloxy.[012S] In a further preferred embodiment, the medium (ad-ditionally) comprises one or more compounds which containa fluorinated dibenzo furan unit, preferably compounds oftheformula IV, preferably of the formula IV-I I,

F F

/

IV-6

F F

R41

R42

IV-11

R41 z42

US 2012/0307177 A115

Dec. 6, 2012

in which the parameters have the respective meanings indi-cated above for formula IV and preferably

[0129] R ' denotes alkyl or alkenyl and

[0130] R denotes alkyl, alkenyl, alkoxy or alkenyloxy.

[0131] In a further preferred embodiment, the medium (ad-ditionally) comprises one or more compounds of the formulaIV selected from the group of the compounds of the formulaeIV-12 to IV-15, preferably from the group of the formulaeIV-12 and IV-14, particularly preferably of the formula IV-12:

each, independently of one another, denote

and/or

where two adjacent rings are very particularly preferablylinked directly, and preferably denote

F FIV-12

F

F FIV-13

R41 Z41 / X /

F F

F F

F

R41 z41 , . /

IV-14

IV-15

where one or more H atoms in the phenylene ring may bereplaced, independently of one another, by F or CN, prefer-

ably by F, and one or two non-adjacent CH2 groups of the

cyclohexylene ring or one ofthe two cyclohexylene rings maybe replaced by 0 atoms.

[0136] In a further preferred embodiment, the medium

comprises one or more compounds of the formula V from the

group of the compounds of the formulae V-I to V-14, prefer-

ably selected from the group of the compounds of the formu-

lae V-I to V-12, preferably from the group V-I to V-7, V-11and V-12 and particularly preferably from the group V- I and

V-4:

R42

R41 Z41 Z42 /R" Rs2

V-I

in which the parameters have the respective meanings indi-cated above under formula IV and preferably

in formulae IV-12 and IV-13

[0132] Z ' denotes CH2MH2, MH2M or asingle bond, preferably CH2 0 or a single bond,particularly preferably CH2 0

in formulae IV-14 and IV-15

[0133] Z ' denotes CH2 CH2 or a single bond, pref-erably a single bond, and

[0134] Z denotes CH2MH2, MH2M or asingle bond, preferably CH2 0 or a single bond,particularly preferably CH2 0

[0135] In a further preferred embodiment, the mediumcomprises one or more compounds of the formula V in whichat least two of the rings

R"

R"

R"

/ X /

/ X /

V-2

V-3

V-4

V-5

A"to

A'4/X /X /

V-6

US 2012/0307177 A116

Dec. 6, 2012

-continued

/X /X /V-7

[0142] The medium according to the invention particularlypreferably comprises compounds of the formula V-I inamounts of 20% by weight or more, in particular 25% byweight or more, very particularly preferably 30% by weightor more, in particular compounds of the formula V-I c'

F F

R" C=CH RszH

V-8

CnH2n+1

V-1c'

V-9

HR" C=CH

R"

R"

Ys

V-10

Rsz

V-11

0 Rsz

V-12

in which[0143] n denotes 3, 4 or 5, and

[0144] R' denotes H, CHs or C~Hs.[0145] In a further preferred embodiment, the mediumcomprises one or more compounds of the formula V-2.[0146] In a further preferred embodiment, the mediumcomprises one or more compounds of the formula V-3. Theproportion of these biphenyls in the mixture as a whole ispreferably 3% by weight or more, in particular 5% by weightor more.[0147] Particularly preferred compounds of the formulaeV-3 are the compounds of the following formulae:

/ X /

R"

R"

/ 4 /

Ys

0 Rsz

V-13

Rsz

V-14

/

//

/ X /

R" /X /X / / X /Ys

in which the parameters have the respective meanings indi-cated above for formula V and[0137] Y denotes H or Fand preferably[013S] R ' denotes alkyl or alkenyl and[0139] R denotes alkyl, alkenyl or alkoxy, preferably

alkyl or alkenyl, particularly preferably alkenyl.[0140] The medium particularly preferably comprises oneor more compound(s) of the formula V-l, selected from thegroup

[0141] of the formula V-I in which R ' denotes vinyl orI-propenyl and R denotes alkyl, preferably n-alkyl,particularly preferably R ' denotes vinyl and Rdenotes propyl, and of the formula V-I in which R ' and

R, independently of one another, denote vinyl orl-propenyl, preferably R ' denotes vinyl and particu-larly preferably R ' and R denote vinyl.

and of these in particular those of the final formula.

[014S] In a preferred embodiment, the medium comprisesone or more compounds of the formula V-4, particularlypreferably one or more compound(s) in which R ' denotesvinyl or I-propenyl and R denotes alkyl, preferably n-alkyl,particularly preferably R ' denotes vinyl and R denotesmethyl.

[0149] In a preferred embodiment, the medium comprisesone or more compounds of the formula V-5, particularlypreferably one or more compound(s) in which R ' denotesalkyl, vinyl or I-propenyl and R denotes alkyl, preferablyn-alkyl.

[0150] In a further preferred embodiment, the mediumcomprises one or more compounds of the formula V-6, pref-erably selected from the group of the compounds PGP-2-3,PGP-2-4, PGP-2-5, PGP-3-3 and PGP-3-4, and from the

US 2012/0307177 A117

Dec. 6, 2012

group of the formulae PGP-1-2V, PGP-2-2V and PGP-3-2V,where the acronyms (abbreviations) are explained in Tables Ato C and illustrated by examples in Table D.[0151] In a further preferred embodiment, the mediumcomprises one or more compounds of the formula V-13.[0152] In a further preferred embodiment, the mediumcomprises one or more compounds of the formula V-14.[0153] The chiral compound or the chiral compoundswhich can be used in component D ofthe liquid-crystal mediain accordance with the present invention is or are selectedfrom the known chiral dopants. Component D preferablyconsists predominantly, particularly preferably essentiallyand very particularly preferably virtually completely of oneor more compounds selected from the group of the com-pounds of the following formulae VI to VIII:

each, independently of one another, denote

/ i, /

VI

R61 A61 Z61 A62 Z A Z62 A64 Z62 R62V W

R72 A76 .-1z

R71 A71 Z71 A72 Z72x

VH

H2C

H2C,,H2C

CH2

CH2VHI

R' —Z'

in which

[0154] R ' and R, R ' to R and R each, independently

ofone another, have the meaning given above for R ' under

formula V, and alternatively denote H, CN, F, Cl, CF2,OCF2, CF2H or OCF2H, and at least one of R ' and Rdenotes a chiral group,

[0155] Z ' and Z, Z ' to Z and Z each, independently

of one another, denote MH2CH2, MH CH

~OO, ~ CO or a single bond, preferably Z ',Z, Z ', Z and Z denotea singlebond, Z, Z andZdenote COO or a single bond, Z preferably denotes

~OO, and Z and Z denote ~ CO

-continuedF F

/ i, /

/ i, /N

/ i, /

A61

A71

to

to

A64

A"u and v, and

x, y and z each, independently of one another, denote 0 or I,preferablyu and v both denote 0 andx and v both denote l.

US 2012/0307177 A118

Dec. 6, 2012

[0156] Particularly preferred embodiments of the presentinvention satisfy one or more of the following conditions.[0157] i. The liquid-crystalline medium has a birefringence

of 0.085 or more.[015S] ii. The liquid-crystalline medium comprises one or

more compounds selected from the group of the sub-for-mulae I-l to 1-45.

[0159] iii. The concentrations of the individual homolo-gous compounds of the formula I in the medium are in therange from I to 40%, preferably from 2 to 35% and par-ticularly preferably from 5 to 30%.

[0160] iv. The proportion ofcompounds of the formula II inthe medium is 10% or more.

[0161] v. The concentrations of the individual homologouscompounds of the formula II are in the range from 2 to16%,preferably from 3 to 12% and particularly preferablyfrom 4 to 10%.

[0162] vi. The liquid-crystalline medium comprises one ormore particularly preferred compounds selected from thegroup of the compounds of the formulae II-I, II-2, II-3and/or II-14, preferably of the formulae CY-n-Om, CY-V-On, CY-nV-Om, CEY-n-Om, CEY-V-On, CEY-nV-Om,PY-n-Om, PY-V-On, PY-nV-Om, LY-n-Om, LY-V-On and/

or LY-nV-Om, where the concentration of the individualhomologous compounds is preferably in the range from2% or more to 15%or less and the total concentration of thecompounds in the medium is 60% or less.

[0163] vii. The liquid-crystalline medium comprises one ormore particularly preferred compounds selected from thegroup of the compounds of the formulae II-4, II-5, II-15and/or II-16, preferably of the formulae CCYn-m, CCY-V-n, CCY-n-m, CCY-n-Om, CCY-V-On, CCY-nV-Om,CPYn-m, CPY-V-n, CPY-nV-m, CPY-n-Om, CPY-V-On,CPY-nV-Om, CLY-n-m, CLY-V-n, LY-nV-m, CLY-n-Om,CLY-V-On, CLY-nV-Om, where the concentration of theindividual homologous compounds is preferably in therange from 2% or more to 20% or less and the total con-centration of the compounds in the medium is 50% or less.

[0164] viii. The liquid-crystalline medium comprises oneor more particularly preferred compounds selected fromthe group of the compounds of the formulae II-6 and/orII-17, preferably of the formulae PPY-n-m, PPYV-n, PPY-nV-m, PYP-n-m, PYP-V-n and/or PYP-nV-m, where theconcentration of the individual homologous compounds inthe case of PYP-n-m, PYP-V-n and PYP-nV-m is prefer-ably in the range from 2% or more to 20% or less and in thecase of PPY-n-m, PPY-V-n and PPY-nV-m is preferably inthe range from 2% or more to 10% or less and the totalconcentration of the compounds in the medium is 30% orless.

[0165] ix. The medium comprises one or more compoundsof the formula III, preferably of the formulae III-I and/orIII-2, particularly preferably of the formula III-2a, wherethe concentration of the individual homologous com-pounds in the medium is preferably 2% or more to 15%orless and the total concentration is 30% or less.

[0166] x. The medium comprises one or more compoundsof the formula IV.

[0167] xi. The medium comprises one or more compoundsof the formula V, preferably in a total concentration of 10%or more to 80% or less.

[016S] xii. The medium comprises one or more particularlypreferred compounds selected from the group of the com-pounds of the formulae V- I and V-4.

alkyl

alkyl

alkyl

alkyl

in which alkyl has the meaning given above and preferablydenotes, in each case independently of one another, alkyl

having I to 6, preferably having 2 to 5, C atoms and particu-

larly preferably n-alkyl.

[0171] xv. The liquid-crystalline medium comprises one ormore compounds of the formula V selected from the groupof the following formulae:

R" CHzO Rsz

R" CHaO Rsz

[0169] xiii. The medium comprises one or more particu-

larly preferred compounds selected from the group of thecompounds of the formulae V-2, V-3, V-5, V-12 and V-13and/or V-7.

[0170] xiv. The liquid-crystalline medium comprises one ormore particularly preferred compounds of the formula V-Iselected from the sub-formulae mentioned below:

US 2012/0307177 A119

Dec. 6, 2012

R"

-continued

COO R~2

R~' COO Rs2

R"

Rs2

R" Rs2

R"

R" Rs2

R"

R"

in which R ' and R have the meanings indicated above, andR ' and R, independently of one another, preferably denotea straight-chain alkyl, alkoxy or alkenyl radical having I or 2to 7 C atoms respectively, particularly preferably straight-chain alkyl, furthermore alkenyl.

[0172] The proportion of these compounds in the mix-ture is preferably 5 to 40% by weight.

[0173] xvi. The liquid-crystalline medium comprises oneor more compounds of the formula V, selected from thegroup of the compounds of the following formulae: CC-n-V and/or CC-n-Vm, CPP-n-m, CGP-n-m and CCOC-n-m, in which the meanings of the acronyms (abbreviations)are explained in Tables A to C and illustrated by examplesin Table D, preferably in a total concentration ofup to 10%or more to 70% or less.

[0174] xvii. The liquid-crystalline medium essentially con-sists of 2% by weight to 80% by weight of one or morecompounds of the formula I,

[0175] 2% by weight to 80% by weight of one or morecompounds of the formula II,

[0176] 2% by weight to 80% by weight of one or morecompounds selected from the group of the compoundsof the formulae III and/or IV, and/or

[0177] 2% by weight to 80% by weight of one or morecompounds of the formula V.

[017S] xviii. The liquid-crystalline medium comprises oneor more compounds of the formula I containing two orthree six-membered or five-membered rings in amounts of1% to 15%, in particular 2% to 12% and very particularlypreferably 3% to 8%, per individual compound.

[0179] xix. The liquid-crystalline medium comprises oneor more compounds of the formula II, preferably inamounts of 2% or more, in particular 5% or more and veryparticularly preferably 5% or more to 30% or less, in par-ticular in the range from 2% or more to 12% or less, perhomologous individual compound.

[01SO] xx. The liquid-crystalline medium comprises one ormore compounds of the formulae II-4 and/or II-5, prefer-ably in a total concentration of 60% or less and in a con-centration of 2% or more, in particular 5% or more and veryparticularly preferably 5% or more to 20% or less, perhomologous individual compound.

[01S1] xxi. The liquid-crystalline medium comprises oneor more compounds of the formulae II-6 and/or II-7, pref-erably in a total concentration of50% or less and preferablyin a concentration of 2% or more to 10% or less, perhomologous individual compound of the formula II-6 andin a concentration of 2% or more to 20% or less perhomologous individual compound of the formula II-6.

[01S2] xxii. The liquid-crystalline medium comprises oneor more compounds of the formula II, preferably inamounts of 2% or more, in particular 5% or more and veryparticularly preferably 5% to 25%, in particular in therange from 2% to 12%, per individual compound.

[01S3] xxiii. The liquid-crystalline medium comprises oneor more compounds of the formula V, preferably inamounts of 3% or more, in particular 5% or more and veryparticularly preferably 5% to 25%, in particular in therange from 2% to 20%, per individual compound.

[01S4] The invention furthermore also relates to an electro-optical display having active-matrix addressing based on theECB effect, characterised in that it contains, as dielectric, aliquid-crystalline medium in accordance with the presentinvention.

[01S5] This electro-optical display preferably has a back-light whose light has no component having a wavelength ofless than 380 nm, preferably less than 400 nm, more prefer-ably less than 410nm, even more preferably less than 420 nm,even more preferably less than 430 nm and very particularlypreferably less than 440 nm. This embodiment is preferablyachieved by using a corresponding cut-off filter having thedesired cut-off wavelength between the backlight and theliquid-crystal medium or particularly preferably by using anLED backlight. In the latter case, it is generally not necessaryto use a cut-off filter.

[01S6] The preferred LCDs in accordance with the presentapplication use an LED backlight. The lifetime of the display,in particular that of the liquid-crystal medium used, can thususually be significantly increased.

[01S7] An alternative design of the LCDs according to theinvention uses an optical cut-off filter between the backlightand the adjacent substrate. In this embodiment, a conven-tional CCFL backlight can also be used without the li fetime ofthe display being excessively impaired. The cut-off filterallows virtually no radiation through below the cut-off wave-Iengh P. „, &&). In this case, however, an upper limit for thetotal concentration (c ) of the alkenyl compounds used(present) in the liquid-crystal medium should preferably beobserved. The maximum tolerable concentration of the alk-

enyl compounds depends primarily here on the voltage hold-

ing ratio necessary for the particular application. Further-more, the maximum tolerable concentration of the alkenylcompounds depends on the cut-off wavelength and the

US 2012/0307177 A120

Dec. 6, 2012

No. X,„, gnm

380400410420430440

c (atkenyts*i/'/o

06

10306080

Note:

*preferably CC-n-Vm, partrcularly preferably CC-3-V.

[0190] The maximum total concentrations of the various

alkenyl or alkynyl compounds depend on the type of thecorresponding compounds used. The maximum total concen-trations for various types of compound are shown in thefollowing table.

Com otmd

X,„, gnm

CC-n-Vm,

CVY- CBY- PBY- CTY-n-Om n-Om n-Om n-Om Total

c „„(atkenyts/atkynyts*i/o/o

400410420

103070

01646

01646

0 0 1026 16 6060 46 100

Note:

*preferably CC-n-Vm, partrcularly preferably CC-3-V.

[0191] The liquid-crystal mixture preferably has a nematicphase range of at least 60 degrees, preferably at least 70degrees and very particularly preferably at least 90 degrees,and a rotational viscosity 7t of at most 115 mPa s at 20' C.[0192] The liquid-crystal medium according to the inven-

tion preferably has a AE of —0.5 or less to —8.0 or more, inparticular —2.5 or less to —6.0 or more, where AE denotes thedielectric anisotropy.

[0193] The rotational viscosity 7t is preferably 115 mPa s

or less, preferably 95 mPa s or less and in particular 85 mPa s

or less.

[0194] The birefringence An of the liquid-crystal mixture isgenerally in the range from 0.06 or more to 0.25 or less,preferably in the range from 0.08 or more to 0.20 or less.

[0195] The threshold voltage Vo of the liquid-crystal mix-ture is generally in the range from 1.2 V or more to 3.0 V orless, preferably in the range from 1.5 V or more to 2.5 V orless.

residual transmission of the cut-off filter used (including thesubstrate) and also, albeit to a lesser extent, on the type ofalkenyl compounds used.

[01SS] Typical representatives of the alkenyl compoundshere are regarded as being the compounds of the type CC-n-Vand CC-n-Vm, particularly CC-3-V and CC-3-VI, in particu-lar CC-3-V (see Table D).[01S9] The following table shows the maximum total con-centrations of this (these) compound(s) in corresponding liq-uid-crystal media on use of cut-off filters having variouscut-off wavelengths. On use ofan LED backlight, which doesnot require a cut-off filter, the shortest wavelength emitted,

generally that of the blue LED, corresponds to this cut-offwavelength.

[0196] The mixtures according to the invention are suitablefor all VA-TFT applications, such as, for example, VAN,MVA, (S)-PVA and ASV. They are furthermore suitable forIPS, FFS and PALC applications of negative AE.[0197] The nematic liquid-crystal mixtures in the displaysaccording to the invention generally comprise two or threecomponents, components A and B and/or C, which them-selves each consist of one or more individual compounds.[019S] For component A, one (or more) individual com-pound(s) having a value of AE~ —0.8 is (are) preferablyselected. This value must be more negative the smaller theproportion ofA in the mixture as a whole.[0199] For component B, one (or more) individual com-pound(s) having a value of AE~ —0.8 is (are) preferablyselected. This value must be more negative the smaller theproportion of B in the mixture as a whole.[0200] Component C has pronounced nematogeneity and aflow viscosity of not greater than 30 mm s ', preferably notgreater than 25 mm s ', at 20' C.[0201] For component B, one (or more) individual com-pound(s) having an absolute value of AE of &0.8 is (are)preferably selected.[0202] Particularly preferred individual compounds incomponent C are extremelylow-viscosity nematic liquidcrystals having a flow viscosity ofnot greater than 18mm s

t, preferably not greater than 12 mm s ', at 20' C.[0203] Component B is monotropically or enantiotropi-cally nematic and is able to prevent the occurrence of smecticphases down to very low temperatures in liquid-crystal mix-tures. For example, if various materials of high nematogene-ity are added to a smectic liquid-crystal mixture, the nemato-geneity of these materials can be compared through thedegree of suppression of smectic phases that is achieved.[0204] A multiplicity of suitable materials is known to theperson skilled in the art from the literature. Particular prefer-ence is given here to compounds of the formula V.[0205] The liquid-crystal mixtures according to the inven-tion preferably comprise 4 to 15, in particular 5 to 12, andparticularly preferably 10 or fewer, compounds of the formu-lae I and (II and/or III and/or IV) and/or V.[0206] Besides compounds selected from the group of theformulae I to V, other constituents may also be present inliquid-crystal mixtures according to the invention, forexample in an amount ofup to 45'/o of the mixture as a whole,but preferably up to 35'/o, in particular up to 10'/o.

[0207] The other constituents of the liquid-crystal mixturesaccording to the invention are preferably selected from nem-atic or nematogenic substances, in particular known sub-stances, from the classes of the azoxybenzenes, benzylidene-anilines, biphenyls, terphenyls, phenyl or cyclohexylbenzoates, phenyl or cyclohexyl cyclohexanecarboxylates,phenylcyclohexanes, cyclohexylbiphenyls, cyclohexylcyclo-hexanes, cyclohexylnaphthalenes, 1,4-biscyclohexylbiphe-nyls or cyclohexylpyrimidines, phenyl- or cyclohexyldiox-anes, optionally halogenated stilbenes, benzyl phenyl ethers,tolans and substituted cinnamic acid esters.[020S] The most important compounds which are suitableas constituents of liquid-crystal mixtures of this type can becharacterised by the formula IV

Rot-L-G-E-Roa IX

in which L and E each denote a carbo- or heterocyclic ringsystem from the group formed by 1,4-disubstituted benzeneand cyclohexane rings, 4,4'-disubstituted biphenyl, phenyl-cyclohexane and cyclohexylcyclohexane systems, 2,5-disub-stituted pyrimidine and 1,3-dioxane rings, 2,6-disubstitutednaphthalene, di- and tetrahydronaphthalene, quinazoline andtetrahydroquinazoline,

US 2012/0307177 A121

Dec. 6, 2012

G denotes MH CHMH CQ

CMOMMO SMH NMF20~CF2

(CHzia

N(01 NMH N(01MH2MH2WHYMH2 S~OO-Phe-COOMF CF~CH2

(CH2120

or a C~ single bond, Q denotes halogen, preferably chlo-rine, or ~N, and R ' and R each denote alkyl, alkenyl,alkoxy, alkanoyloxy (or oxaalkyl) or alkoxycarbonyloxy hav-ing up to 18, preferably up to 8, carbon atoms, or one of theseradicals alternatively denotes CN, NC, NO2, NCS, CFs,OCFs, F, Cl or Br.

[0209] In most of these compounds, R ' and R are differ-ent from one another, one of these radicals usually being an

alkyl or alkoxy group. Other variants of the proposed sub-

stituents are also common. Many such substances or alsomixtures thereof are commercially available. All these sub-

stances can be prepared by methods known from the litera-ture.

[0210] The synthesis of the particularly preferred com-pounds of the formula I in which the ring A' denotes cyclo-hexane and Z' is a C~ triple bond, i.e. C C, ispreferably carried out as depicted in the following reactionscheme, Scheme 1. The cross-coupling of aryl halides (bro-mides 2 or also iodides) to suitable alkynes I (Sonogashiracoupling) gives the desired compounds of the type "CTY".The alkynes I required are accessible, for example, fromcorresponding aldehydes by a Corey-Fuchs reaction.

Scheme I: Synthesis of compounds of the formula I (compounds 3 in particular)

in which A denotes cyclohexane and Z is a—C—C triple bond —C=C—12 12

(compounds of the type "CTY"i.

F F

R11 A11 z1 1

I

+ I3r

y /2

(PPhsizPdCI2, CuISonogashira coupling

NEts

F F

R11 A11 z1 1

[0211] The compounds 3 are also suitable starting materialsfor the synthesis of the compounds I in which the ring A'denotes cyclohexane and Z' is a C C double bondMH CH (see Scheme 2). The CM triple bond ishydrogenated to a C C double bond by Lindlar hydrogena-tion using "poisoned" palladium catalysts. The Z-alkenes areobtained here. The isomerisation to the desired compounds 4having an E-configured double bond generally proceeds tocompletion.

Scheme 2: Synthesis of compounds I (compounds 4 in particular) in which A denotes cyclohexane

and Z is a C—C double bond —CH=CH —(compounds of the type "CVY"i.

F F

R11 A11 Z11

1. Lindtar hydrogenation2. Isomerisation

e.g. benzenesutftnic acid

US 2012/0307177 A122

Dec. 6, 2012

Rlt Alt Ztt

-continuedF F

Z" A" R"/ a

Alternatively, the compounds of type 4 can also be obtainedby a Wittig reaction of the aldehydes 6 using triphenylphos-phonium salts 5 (see Scheme 3).

Scheme gu Synthesis of compounds of the formula I (compounds 4 in particular) in which A denotes cyclohexane

and Z is a C—C double bond —CH=CH —(compounds of the type "CVY"1by Wittig reaction.

F F

Rlt Alt Ztt0

PPhs + Br

1. Kot-Bu2. PhSOrH

6

Rl 1 Alt

zlzz

F F

[0212] The synthesis of the particularly preferred com-pounds of the formula I in which the ring A' denotes cyclo-hexane and Z' is a fluorinated C C double bond

CF CF is preferably carried out as depicted in Scheme4. The synthesis starts from cyclohexanols 7, which are firstlyconverted into the chlorides 8 thereof. From these, cyclohexy-llithium compounds 9 are generated, for example using Li/di-

tert-butylbiphenyl, and are then reacted directly with thebuilding block 10. This gives the compounds 11.The silyl

group is cleaved off by reaction with TBAF. This gives thecompounds 12.These are then converted into suitable halides13 by deprotonation using t-BuLi and scavenging of theresultant organolithium compound using bromine or iodine.The alkenyl iodides or bromides 13 are obtained exclusivelyin the preferred E form, and they are suitable reactants forgiving the compounds I having difluoroethylene bridges(compounds 15 in Scheme 4) in a palladium-catalysed cross-coupling to the arylboronic acids 14.

Scheme 4: Synthesis of compounds of the formula I (compounds 15 in particular)

in which A denotes cyclohexane and Z is a fluorinated C—C double bond=CF—(compo

Rl 1 Alt

zlzz

the type "CBStltCIr Li, THFtoluene 4,4'-di-tert-butylbiphenyl

OH ~ R" A" Z" Cl

FSIEts

Rl 1 Alt Z" I.i10

THFRl 1 Alt

zlzz

SIEts TBAF

/ THF

11

US 2012/0307177 A123

Dec. 6, 2012

Rl 1 Alt

zlzz-continued

F 1. t-BuLi

H I. X (X B, I2

Rlt Alt

zlzz

12

F 1. t-BuLi F

/

13

F F

13

(HOiqB

~ /Z' A' „R'

14

[Pdol

Rl 1 Alt

zlzz

F F F

15

[0213] The concentration of the compounds of the formulaIX in the mixture as a whole is preferably 1% to 25%, par-ticularly preferably 1% to 15% and very particularly prefer-ably 2% to 9%.[0214] The media according to the invention may option-ally also comprise a dielectrically positive component, whosetotal concentration is preferably 10% or less, based on theentire medium.

[0215] In a preferred embodiment, the liquid-crystal mediaaccording to the invention, or liquid-crystal media employedin accordance with the invention, comprise in total, based onthe mixture as a whole, 5% or more to 60% or less, preferably10%or more to 50% or less, preferably 15% or more to 40%or less andparticularly preferably 20% ormoreto 35% or lessand very particularly preferably 25% or more to 30% or lessof component A and

[0216] 1%or more to 45% or less, preferably 2% or more to40% or less, preferably 3% or more to 35% or less andparticularly preferably 5% or more to 30% or less and veryparticularly preferably 10% or more to 20% or less of com-ponent B and

[0217] 5% or more to 80% or less, preferably 25% or moreto 75% or less, particularly preferably 35% or more to 70% orless and very particularly preferably 40% or more to 65% orless of component C.[0218] The liquid-crystal media according to the invention,or liquid-crystal media employed in accordance with theinvention, preferably have a nematic phase from in each caseat least —20' C. or less to 70' C. or more, particularly prefer-ably from —30' C. or less to 80' C. or more, very particularlypreferably from —40' C. or less to 85' C. or more and mostpreferably from —40' C. or less to 105' C. or more.

[0219] The expression "have a nematic phase" here means

on the one hand that no smectic phase and no crystallisation

are observed at low temperatures at the corresponding tem-

perature and on the other hand that no clearing occurs onheating out of the nematic phase. The investigation at lowtemperatures is carried out in a flow viscometer at the corre-

sponding temperature and checked by storage in test cellshaving a cell thickness corresponding to the electro-opticalapplication for at least 100 hours. If the storage stability at atemperature of —20' C. in a corresponding test cell is 1000 hor more, the medium is regarded as stable at this temperature.At temperatures of —30' C. and —40' C., the correspondingtimes are 500 h and 250 h respectively. At high temperatures,the clearing point is measured in capillaries by conventionalmethods.

[0220] In addition, the liquid-crystal media according tothe invention, or liquid-crystal media employed in accor-dance with the invention, have high values for the voltageholding ratio in liquid-crystal cells.

[0221] In freshly filled cells at 20' C. in the cells, these aregreater than or equal to 95%, preferably greater than or equalto 97%, particularly preferably greater than or equal to 98%and very particularly preferably greater than or equal to 99%,and after 5 minutes in the oven at 100' C. in the cells, these aregreater than or equal to 90%, preferably greater than or equalto 93%, particularly preferably greater than or equal to 96%and very particularly preferably greater than or equal to 98%.[0222] These preferred values for the individual physicalproperties are preferably also in each case maintained by themedia according to the invention in combination with oneanother.

US 2012/0307177 A124

Dec. 6, 2012

[0223] In the present application, the term "compounds",also written as "compound(s)", means both one and also aplurality of compounds, unless explicitly indicated other-wise.[0224] For the present invention, the following definitions

apply in connection with the specification of the constituentsof the compositions, unless indicated otherwise in individualcases:

[0225] "comprise": the concentration of the constituentsin question in the composition is preferably 5% or more,particularly preferably 10% or more, very particularlypreferably 20% or more,

[0226] "predominantly consist of': the concentration ofthe constituents in question in the composition is pref-erably 50% or more, particularly preferably 55% ormore and very particularly preferably 60% or more,

[0227] "essentially consist of': the concentration of theconstituents in question in the composition is preferably80% or more, particularly preferably 90% or more andvery particularly preferably 95% or more, and

[0228] "virtually completely consist of'. the concentra-tion of the constituents in question in the composition ispreferably 98% or more, particularly preferably 99% ormore and very particularly preferably 100.0%.

[0229] This applies both to the media as compositions withtheir constituents, which can be components and compounds,and also to the components with their constituents, the com-pounds. Only in relation to the concentration of an individualcompound relative to the medium as a whole does the termcomprise mean: the concentration of the compound in ques-tion is preferably 1% or more, particularly preferably 2% ormore, very particularly preferably 4% or more.[0230] For the present invention, "~"means less than orequal to, preferably less than, and "~"means greater than orequal to, preferably greater than.[0231] For the present invention,

H

and "Cyc"

[0232] denote trans-1, 4-cyclohexylene, and

[0233] and "Phe"denote 1,4-phenylene.[0234] For the present invention, the expression "dielectri-cally positive compounds" means compounds having a AE of&1.5, the expression "dielectrically neutral compounds"means those where —1.5~AE1.5 and the expression "dielec-trically negative compounds" means those where AE&—1.5.The dielectric anisotropy of the compounds is determinedhere by dissolving 10%of the compounds in a liquid-crystal-

line host and determining the capacitance of the resultantmixture in each case in at least one test cell having a cellthickness of 20 pm with homeotropic and with homogeneoussurface alignment at I kHz. The measurement voltage istypically 0.5 V to 1.0V, but is always lower than the capacitivethreshold of the respective liquid-crystal mixture investi-gated.

[0235] The host mixture used for dielectrically positive anddielectrically neutral compounds is ZLI-4792 and that usedfor dielectrically negative compounds is ZLI-2857, both fromMerck KGaA, Germany. The values for the respective com-pounds to be investigated are obtained from the change in thedielectric constant of the host mixture after addition of thecompound to be investigated and extrapolation to 100%ofthecompound employed. The compound to be investigated isdissolved in the host mixture in an amount of 10%. If thesolubility of the substance is too low for this purpose, theconcentration is halved in steps until the investigation can becarried out at the desired temperature.

[0236] The liquid-crystal media according to the invention,or liquid-crystal media employed in accordance with theinvention, may, if necessary, also comprise further additives,such as, for example, stabilisers and/or pleochroic dyes and/

or chiral dopants in the usual amounts. The amount of theseadditives employed is preferably in total 0% or more to 10%or less, based on the amount of the entire mixture, particularlypreferably 0.1% or more to 6% or less. The concentration ofthe individual compounds employed is preferably 0.1% ormore to 3% or less. The concentration of these and similaradditives is generally not taken into account when specifyingthe concentrations and concentration ranges of the liquid-crystal compounds in the liquid-crystal media.

[0237] In a preferred embodiment, the liquid-crystal mediaaccording to the invention, or liquid-crystal media employedin accordance with the invention, comprise a polymer precur-sor which comprises one or more reactive compounds, pref-erably reactive mesogens, and, ifnecessary, also further addi-tives, such as, for example, polymerisation initiators and/or

polymerisation moderators, in the usual amounts. Theamount of these additives employed is in total 0% or more to10% or less, based on the amount of the entire mixture,preferably 0.1% or more to 2% or less. The concentration ofthese and similar additives is not taken into account whenspeci fying the concentrations and concentration ranges of theliquid-crystal compounds in the liquid-crystal media.

[0238] The compositions consist of a plurality of com-pounds, preferably 3 or more to 30 or fewer, particularlypreferably 6 or more to 20 or fewer and very particularlypreferably 10 or more to 16 or fewer compounds, which aremixed in a conventional manner. In general, the desiredamount of the components used in lesser amount is dissolvedin the components making up the principal constituent of themixture. This is advantageously carried out at elevated tem-perature. If the selected temperature is above the clearingpoint of the principal constituent, completion of the dissolu-tion operation is particularly easy to observe. However, it isalso possible to prepare the liquid-crystal mixtures in otherconventional ways, for example using pre-mixes or from aso-called "multibottle system".

[0239] It goes without saying to the person skilled in the artthat the media according to the invention for use in VA, IPS,FFS or PSVA displays may also comprise compounds inwhich, for example, H, N, 0, Cl, F have been replaced by thecorresponding isotopes.

US 2012/0307177 A125

Dec. 6, 2012

[0240] The structure of the liquid-crystal displays accord-ing to the invention corresponds to the conventional geom-etry, as described, for example, in EP-A 0 240 379.[0241] The liquid-crystal phases according to the inventioncan be modified by means of suitable additives in such a waythat they can be employed in any type of, for example, ECB,VAN, IPS, GH or ASM-VA LCD display that has been dis-closed to date.

[0242] Table E below indicates possible dopants which canbe added to the mixtures according to the invention. If themixtures comprise one or more dopants, where the dopant ordopants is (are) employed in amounts of 0.01 to 4% byweight, preferably 0.1 to 1.0% by weight.

[0243] Stabilisers which can be added, for example, to themixtures according to the invention, preferably in amounts of0.01 to 6% by weight, in particular 0.1 to 3% by weight, arementioned below in Table F.

[0244] For the purposes of the present invention, all con-centrations are, unless explicitly noted otherwise, indicated inpercent by weight and relate to the corresponding mixture ormixture component, unless explicitly indicated otherwise.

[0245] All temperature values indicated in the presentapplication, such as, for example, the melting point T(C,N),the smectic (S) to nematic (N) phase transition T(S,N) and theclearing point T(N, I), are indicated in degrees Celsius (' C.)and all temperature differences are correspondingly indicatedin differential degrees (' or degrees), unless explicitly indi-cated otherwise.

[0246] For the present invention, the term "threshold volt-age" relates to the capacitive threshold (Vo), also known asthe Freedericks threshold, unless explicitly indicated other-wise.

[0247] All physical properties are and have been deter-mined in accordance with "Merck Liquid Crystals, PhysicalProperties ofLiquid Crystals", status November 1997,MerckKGaA, Germany, and apply to a temperature of 20' C., andAn is determined at 589 nm and AE at I kHz, unless explicitlyindicated otherwise in each case.

[0248] The electro-optical properties, for example thethreshold voltage (Vo) (capacitive measurement), are, as isthe switching behaviour, determined in test cells produced atMerck Japan Ltd. The measurement cells have soda-limeglass substrates and are constructed in an ECB or VA con-figuration with polyimide alignment layers (SE-1211 withdiluent **26(mixing ratio I:I), both from Nissan Chemicals,Japan), which have been rubbed perpendicular to one anotherand effect a homeotropic alignment of the liquid crystals. Thesurface area of the transparent, virtually square electrodes ofITOis I cm .

[0249] Unless indicated otherwise, a chiral dopant is notadded to the liquid-crystal mixtures used, but the latter arealso particularly suitable for applications in which doping ofthis type is necessary.

[0250] The voltage holding ratio is determined in test cellsproduced at Merck Japan Ltd. The measurement cells havesoda-lime glass substrates and are constructed with polyim-ide alignment layers (SE-1211 from Nissan Chemicals Ltd. ,

Japan), which homeotropically align the liquid-crystalmedia, with a layer thickness of 50 nm which have beenrubbed perpendicular to one another. The layer thickness ofthe liquid-crystal media is uniformly 6.0 pm. The surface areaof the transparent electrodes of ITO is I cm .

[0251] The voltage holding ratio is determined at 20' C.(HR~o) and after 5 minutes in the oven at 100' C (HRyoo).The voltage used has a frequency of 60 Hz.

[0252] The rotational viscosity is determined using therotating permanent magnet method and the flow viscosity ina modified Ubbelohde viscometer. For liquid-crystal mix-tures ZLI-2293, ZLI-4792 and MLC-6608, all products fromMerck KGaA, Darmstadt, Germany, the rotational viscosityvalues determined at 20' C. are 161mPa s, 133mPa s and 186mPa s respectively, and the flow viscosity values (v) are 21mm s ', 14mm s ' and 27mm s ' respectively.

[0253] The following symbols are used in the present appli-cation:

[0254] Vo threshold voltage, capacitive [V] at 20' C.,[0255] n, extraordinary refractive index measured at 20' C.

and 589 nm,

[0256] n ordinary refractive index measured at 20' C. and589 nm,

[0257] An optical anisotropy measured at 20' C. and 589nm,

[0258] E~ dielectric permittivity perpendicular to thedirector at 20' C. and I kHz,

[0259] E dielectric permittivity parallel to the director at20' C. and I kHz,

[0260] AE dielectric anisotropy at 20' C. and I kHz,

[0261] T(N, I) or

[0262] cl.p. clearing point [' C.],[0263] 7, rotational viscosity measured at 20' C. [mPa s],[0264] K, elastic constant, "splay" deformation at 20' C.

[pN],[0265] K~ elastic constant, "twist" deformation at 20' C.

[pN],[0266] Ka elastic constant, "bend" deformation at 20' C.

[pN], and

[0267] LTS low-temperature stability (phase stability),determined in test cells.

[0268] The following examples explain the present inven-

tion without limiting it. However, they show the personskilled in the art preferred mixture concepts with compoundspreferably to be employed and the respective concentrationsthereof and combinations thereof with one another. In addi-tion, the examples illustrate the properties and property com-binations that are accessible.

[0269] For the present invention and in the followingexamples, the structures of the liquid-crystal compounds areindicated by means ofacronyms, with the transformation intochemical formulae taking place in accordance with Tables Ato C below. All radicals C H~ „C H~, and C,H», orC H~, C H~ and C,H» are straight-chain alkyl radicals oralkylene radicals, in each case having n, m and I C atomsrespectively. Table A shows the codes for the ring elements ofthe nuclei of the compound, Table B lists the bridging units,and Table C lists the meanings of the symbols for the left- andright-hand end groups of the molecules. The acronyms arecomposed of the codes for the ring elements with optionallinking groups, followed by a first hyphen and the codes forthe left-hand end group, and a second hyphen and the codesfor the right-hand end group. Table D shows illustrative struc-tures of compounds together with their respective abbrevia-tions.

US 2012/0307177 A126

Dec. 6, 2012

TABLE A

Ring elements

Al

Ul

F F

P(F, Cl)Y F Cl P(C1, F)Y Cl

n3f F F n3fl F F

//

US 2012/0307177 A127

Dec. 6, 2012

TABLE A-continued

tH2f

Ring elements

F F tH2fl F F

o2f F F o2fl F F

/

dh

FF F

KI FF F

LI

Fl

TABLE B TABLE B-continued

EVTWB

Bridging units

MHrMCHrMH CH

CMFrMCFrMF CF

ZX0Q

MOMMF CHMHrMOMFrMO

Bridging units

ZIXIOIQI

MMOMH CFMMHrMMFr

TABLE C

End groups

On the left individually orin combination

On the right individually orin combination

-n-

-nO--V-

-nV-

-Vn-

-nVm-

-N-

C„Hr„ t

CHr CH

C„Hr„~tMH CH

CHr CHM„Hr„C„Hr„~tMH CH

N C

C Hr

-n

-nO-V-nV-Vn-nVm

-N

M„Hr„ t

MH CHrM„Hr„MCH CHrMH CHM„Hr„~tM„Hr„MCH CH C Hr

N

US 2012/0307177 A128

Dec. 6, 2012

TABLE C-continued

End groups

-s--F--CL--M--D--T--MO--DO-—TO--A-

-NA-

S C NFClCFHzCFzHCFsCFHzOCFzHOCFsOHM CC„Hz„ tM CN CM C

-s-F-CL-M-D-T-OM-OD-OT-A-An-AN

N C SFClCFHzCFzHCFsOCFHzOCFzHOCFsC C HC C C„Hz„,C C C N

On the left only in combination On the right only in combination

—...n. ..—

—...M. ..—

—...D ...—

—...V. ..—

—...Z. ..—

—...ZI. ..—

—...K...—

—...w. ..—

M„Hz„MFHMFzMH CHMOMMMOMOMF CF

—...n. ..—...M. ..—...D ...—...V. ..—...Z. ..—...ZI. ..—...K...—...w. ..

C„Hz„CFHCFzCH CHCO~OMOCOCF CF

in which n and m are each integers, and the three dots ".. . "are place markers for other abbreviations from this table.[0270] Besides the compounds of the formula I, the mix-tures according to the invention preferably comprise one ormore compounds of the compounds mentioned below.[0271] The following abbreviations are used, where n, mand z each, independently of one another, denote an integer,preferably 1 to 7, and z particularly preferably denotes 2.

TABLE D

n zn+t C Hz~t

CC-n-m

n zn+t 0—C Hzn+t

CC-n-Om

n zn+t CH=CHz

CC-n-V

CnHzn+t CH=CH —CnHzn+t

CC-n-Vm

n zn+t (C Hair CH CHz

CC-n-zV

US 2012/0307177 A129

Dec. 6, 2012

TABLE D-continued

C„Hz,n ) (CHzin CH CH CnHznn

CC-n-zVm

HzC=CH CH=CHz

CC-V-V

CHz=CH (CHzin CH CHz

CC-V-zV

CHz=CH CH=CH —CnHznn )

CC-V-Vm

CHz —CH—(CHzin (CHzin CH CHz

CC-Vn-zV

CnHznn )—CH=CH (CHzin CH CHz

CC-nV-zV

CnHznn )—CH =CH CH=CH —CnHz~)

CC-nV-Vm

CnHzn+1

CP-n-m

C„Hz„n)—0

CP-nO-m

n zn+1 o—C Hz~i

CP-n-Om

CnHzn+1

F F

/

CY-n-m

US 2012/0307177 A130

Dec. 6, 2012

TABLE D-continued

F F

CnHzn+1

CY-n-Om

F F

CHz=CH

CY-V-m

F F

CHz=CH o—C Hz~i

CY-V-Om

F F

CnHznn )—CHz —CH

CY-nV-Om

F F

CHz CH (CHzin

CY-Vz-Om

F F

CnHznn-& CHz:CH (CHzin/

m 2m+1

CY-nVz-Om

F F

CnHzn+1 0—CH=CHz

CY-n-OV

F F

n zn+1 0—CHz —CH=CHz

CY-n-01 V

US 2012/0307177 A131

Dec. 6, 2012

TABLE D-continued

F F

n zn+1 0—C(—CHgi=CHz

CY-n-OC(CH3i=CH2

F F

CHz —CH CHz —CHz /m 2m+1

CEY-V-m

F F

C Hz+& CO 0 0 C Hz

CZY-n-Om

F F

C„Hz~) (Oi—C Hz J

PY-n-(Oim

F F

CnHz+i

CCY-n-m

F F

CnHzn+1

CCY-n-Om

F F

n zn+1 (CHzi 0 C Hz

CCY-n-zOm

F F

CHz=CH

CCY-V-m

US 2012/0307177 A132

Dec. 6, 2012

TABLE D-continued

F F

CnHznn )—CH= CH

CCY-nV-m

F F

CnHznn-) CH:CH (CHziz/

m 2m+1

CCY-nVz-m

F F

CHz=CH

CCY-V-Om

F F

CnHznn )—CH=CH o—C Hz~i

CCY-nV-Om

F F

CHz CH (CHziz O—C.H,.+,

CCY-Vz-Om

F F

CnHznn-) CH=CH (CHziz

CCY-nVz-Om

F F

CnHzn+1 CO—O / ~ O—C.Hz~,

CCZY-n-Om

F F

CnHz+i / X /CPY-n-m

US 2012/0307177 A133

Dec. 6, 2012

TABLE D-continued

F F

CnH2n+1O / X /CPY-nO-m

F F

CnH2n+1 / X /CPY-n-Om

F F

CH2=CH / X /CPY-V-Om

F F

C„Hn, n ) / X /PYP-n-m

F F

CnH2n+~

g / / X /PYP-n-Om

F F

CnH2n+1 / X /CPYC-n-m

C H2n+&

F F F

n 2n+1 / X /CYYC-n-m

C H2n+&

F F F

n 2n+1 / X /CCYY-n-(Oim

US 2012/0307177 A134

Dec. 6, 2012

TABLE D-continued

F F

CnH2n+1 / X/ X/CPYP-n-m

F F

CnH2n+1 / X/ X/CPYP-n-mV

F F

n 2n+1 / X/ X/CPYG-n-Om

F F

n 2n+1 / X/ X/CPGIY-n-m

F F

/ X /PYGP-n-m

/ X /

F F

CnH2nn-) CF2 0 (Oi CnH2nn-)

CQY-n-(Oim

F F

CnH2n+1 CF2 0 (Oi C H2

CCQY-n-(Oim

F F

CnH2n+1 CF2 0 (Oi C H2

CPQY-n-(Oim

US 2012/0307177 A135

Dec. 6, 2012

TABLE D-continued

F F

CnH2nn-) CF2 0 (Oi CnH2nn )

CQIY-n-(Oim

F F

CnH2n+1 0 CF2 (Oi C H2

CCQIY-n-(Oim

F F

CnH2n+1 0 CF2 (Oi C H2

CPQIY-n-(Oim

F Cl

CnH2n+1 0—C H2n+&

CP(F, Clin-Om

F Cl

CnH2n+1

CCP(F, Clin-Om

Cl F

n 2n+1 o—C H2~i

CP(CI, Fi-n-Om

Cl F

CnH2n+1

CCP(CI, Fi-n-Om

F F

CnH2n+1

CK-n-F

US 2012/0307177 A136

Dec. 6, 2012

TABLE D-continued

CnH2n+1

F F

/C H2~&

Cn3f-n-m

n 2n+1

F F

/0—C H2n)

Cn3f-n-Om

F F

/C„Hn, n ) C H2n+&

CEn3f-n-m

F F

/CnH2n+1 0—C H2~&

CEn3f-n-Om

n 2n+1

F F

/C H2n+&

CCn3f-n-m

F F

CnH2n+1

0—C H2n)

CCn3f-n-Om

F F

n 2n+1

C H2~&//

Cn2f-n-m

US 2012/0307177 A137

Dec. 6, 2012

TABLE D-continued

F F

n 2n+1

o—C H2~i

/

Cn2f-n-Om

F F

/CnH2n+1

C&2f-n-m

F F

CnH2n+1

C&2f-n-Om

F F

n 2n+1

C H2~&

Co2fl-n-m

F F

CnH2n+1

0—C H2n)

Co2fl-n-Om

F F

CnH2n+1

C H2n+&

CCo2fl-n-m

CnH2n+1

F F

/0—C H2n)

CCo2fl-n-Om

US 2012/0307177 A138

Dec. 6, 2012

TABLE D-continued

F F

/CnH~+i C H2m+&

COo3fl-n-m

F F

/CnH2n+1 0—C H2n)

COo2fl-n-Om

F F

/n 2m+1 C H2m+&

CCOo2fl-n-m

F F

/n 2m+1 0—C H2n)

CCOo2fl-n-Om

F F

n 2m+1

LY-n-m

F F

n 2m+1/

m 2m+1

LY-n-Om

F F

CH2=CH /m 2m+1

LY-V-m

F F

CH2=CH

LY-V-Om

US 2012/0307177 A139

Dec. 6, 2012

TABLE D-continued

F F

C„Hn, n )

CLY-n-m

F F

n 2m+1

CLY-n-Om

F F

C„Hn, n )/ X /

m 2m+1

LGIY-n-m

F F

n 2m+1/ X /

m 2m+1

LGIY-n-Om

C„Hn, n )

F F

/ X / C H2m+&

LYLI-n-m

CnH2n+1

PBY-n-m

n 2m+1

PBY-n-Om

C„H2„n )—0

PBY-nO-Om

US 2012/0307177 A140

Dec. 6, 2012

TABLE D-continued

F F F

n 2n+1

CBY-n-m

F F F

n 2n+1

CBY-n-Om

F F

n 2n+1

CCBY-n-Om

F F

n 2n+1

CXIY-n-Om

CH2=CH

F F

m 2m+1

CVY-V-m

CnH2n+1

F F

O—C.H,.+,

CVY-n-Om

[0272] Table E shows chiral dopants which are preferablyemployed in the mixtures according to the invention.

TABLE E

C2Hg —CH —CH20 CN

CHs

C 15

C2Hg —CH —CH2 CN

CHs

CB 15

US 2012/0307177 A141

Dec. 6, 2012

TABLE E-continued

0

C6HJ3 CH —0

CH3 0 CSHJ J

CM 21

C6HJ30 0R S-811/S-811

CH3

C3H7

CM 4'-1

CH3

0 0CM 45

""0 0CM 47

H3C

H3Ci,

H3C

CH3

CH3

0

CJJH3 7

0CN

C3HJ J H COO 8 OCO H C3HJ J

R-1011/S-1011

US 2012/0307177 A142

Dec. 6, 2012

TABLE E-continued

C3H/ H

CH3

OCH —C6HJ3

R-2011/S-2011

C3H/ H

F F

H Q 0

R-3011/S-3011

C3HJ J

F

CH3

OCH —C6HJ3

R-4011/S-4011

H C3H/

R-5011/S-5011

[0273] Compounds selected from the group of the com-pounds from Table E.

TABLE F

HO CH3 OH

US 2012/0307177 A143

Dec. 6, 2012

TABLE F-continued

HO S OH

CnH2n+1 H Q QH

CnH2nn-) OH

0 QH

CnH2n+10 OH

HO CH2 OH

0 0 QH—0

US 2012/0307177 A144

Dec. 6, 2012

TABLE F-continued

H37C Jg—COO —C2H4 OH

n 2n+1 H 0 cN

OH

H|gC7 OH

OH

NN

OH

HO

OH

US 2012/0307177 A145

Dec. 6, 2012

TABLE F-continued

HO OH

O~ ~O

C)H|7

~~ ~

S

CgH|7

OH

OH

HO

US 2012/0307177 A146

Dec. 6, 2012

TABLE F-continued

0 0 OH

0 QH

0 QH

N~ /N~/

OH

/ X

N

N

HO

US 2012/0307177 A147

Dec. 6, 2012

TABLE F-continued

OHN

N

HO

/N

~ /

HO

/N

~ /

N

N

HO

/ iN

~ /

HO

US 2012/0307177 A148

Dec. 6, 2012

TABLE F-continued

N +N OH

N +N OH

US 2012/0307177 A149

Dec. 6, 2012

TABLE F-continued

0 0

0—CgH|7

N

0 0

0—CgH|7

US 2012/0307177 A150

Dec. 6, 2012

TABLE F-continued

—N

N—

—N

N—

CgHt7

sty~~

S

CgHt7

(n here denotes an mteger from 1 to 12l

[0274] In a preferred embodiment of the present invention,the media according to the invention comprise one or morecompounds selected from the group of the compounds fromTable F.

SUBSTANCE EXAMPLES

Example I

Preparation of l-ethoxy-2, 3-difluoro-4-(4-propvlcy-clohexylethynyl)benzene ("CTY-3-02")

[0275] The compound I -ethoxy-2, 3-difluoro-4-(4-propyl-cyclohexylethynyl)benzene ("CTY-3-02") according to theinvention is synthesised as described below.

copper(I) iodide in 440 ml of triethylamine is warmed at 50'C. for 19 h. After cooling, the mixture is diluted with MTBEand neutralised using dil. hydrochloric acid. The organicphase is separated off, and the aqueous phase is extracted withMTBE. The combined organic phases are washed withsodium chloride solution and dried using sodium sulfate. Thesolution is concentrated to dryness, and the residue is purified

by column chromatography (Si02, n-heptane:chlorobu-tane=9: I).The further purification is carried out by recrystal-lisation from n-heptane, giving l-ethoxy-2, 3-difluoro-4-(4-

propylcyclohexylethynyl)benzene as a colourless solid (m.p.64' C.). This has the phase sequence: C 64' C. I. The prop-erties, extrapolated from a 10% solution in ZLI-4792, are:

F F

K /

(PPhs12PdC12,

Cut NEts

F F

X /

T(N, I) (=cl.p.)=56' C.;

[0277] AE=—53;An=0. 1438 and

yt=72 mPa s.

[0278] 'H-NMR (300 MHz, CHClg): 6=7.07-6.99 (m, I H,H, ), 6.65-6.58 (m, IH, H, ), 4.10 (q, 2H, J=7.0 Hz,~CH2CHg), 2.46-2.34 (m, IH, H. . .), 2.09-2.00 (m,2H, H h h, ), 1.83-1.73(m, 2H, H h h, ), 1.55-1.12(m, IOH,

[0279] ' F-NMR (282 MHz, CHClg): ft=—134.6 (dd, IF,J=19.4 Hz, J=73 Hz), —158.9 (dm, IF, J=19.4 Hz).

[0280] MS (EI): m/e (%)=306 (32, M ), 210 (100).

[0276] A mixture of 20.6 g (0.14 mol) of I-ethynyl-4-pro-pylcyclohexane, 25.0 g (0.11 mol) of I -bromo-4-ethoxy-2, 3-difluorobenzene, 2.22 g (3.16 mmol) of bis(trlphenylphos-phine)palladium(II) chloride and 603 mg (3.16 mmol) of

Examples 2 to 19

[0281] The following compounds are synthesised analo-

gously to the compound of Substance Example 1.

US 2012/0307177 A151

Dec. 6, 2012

Stlb.

Ex. Snucturat formula Acronym Physical data

F F

i /

CCTY-3- C 87 N 215 I02 cl.p. = 225' C.

Aa = —s.6

An = 0.1706

F F

i /

CTY-3-04

C 39 N (35) Icl.p. = 32' C.Aa = —5.3An = 0.1334yt = 66mPas

F F

i /

CTY-5-02

C42N531cl.p. = 52' C.Aa = —5.4An = 0.1434yt = 110mPa s

F F

i /

CTY-5-03

C 36 N421cl.p. = 45' C.Aa = —5.0An = 0.1284

yt = 106 mPa s

F F CTY-3-1 C 421cl.p. = —I' C.Aa = —2.0An = 0.1284

yt = 32 mPa s

F F

'' LCCTY-3-03

C 88 N 2041cl.p. = 218' C.Aa = —5.3An = 0.1655

F F CTY-3-01

C 361cl.p. = 14' C.Aa = —5.3An = 0.1394yt = 69 mPa s

F F CCTY-3-I

C 94 N 186 Icl.p. = 203' C.Aa = —2.4An = 0.1706

10 F F CCTY-5- C 67 SmC (55)04 SmA 134 N

196 Icl.p. = 214' C.Aa = —5.1

An = 0.1545

US 2012/0307177 A152

Dec. 6, 2012

-continued

Stlb.

Ex. Snucturat formula Acronym Physical data

F F

/ X /

CTYP-3- C 94 N 1641I cl.p. = 182' C.

Aa = —2.4An = 0.2425

12 F F

X /

CCTY-3- C 73 SmA 8304 N 1971

cl.p. = 211' C.Aa = —5.3An = 0.1592

13 F F F

K/ K/

CTYY-3-03

C 78 N 143 Icl.p. = 145' C.Aa = —8.1

An = 0.2085

14 F F

h /

CCTY-5- C 77 SmA 11703 N 2001

cl.p. = 218' C.Aa = —5.4An = 0.1645

F F CCTY-Vl

C 53 N 1741cl.p. = 183' C.Aa = —2.6An = 0.1695

16 F F

X /

CCTY-V-02

C 86N1991cl.p. = 211' C.Aa = —5.7An = 0.1844

17 F F

X /

CTY-5-04

C 31 N461cl.p. = 48' C.Aa = —5.1

An = 0.1353yt = 111mPa s

18 F F

X /

CCTY-IV-02

C 110 N 251 Icl.p. = 250' C.Aa = —s.6

An = 0.1811

19 F F

X /

CTY-V-02

C 521cl.p. = 11' C.Aa = —6.3An = 0.1441

yt = 53 mPa s

US 2012/0307177 A153

Dec. 6, 2012

Example 20I -Butoxy-2, 3-difluoro-4-[(E)-2-(4-pentylcyclohexyl)

vinyl]-benzene ("CVY-5-04")[02S2] The compound I-butoxy-2, 3-difluoro-4-[(E)-2-(4-pentylcyclohexyl)vinyl]-benzene ("CVY-5-04") accordingto the invention is synthesised as described below.

F F

H

0 lead-poisoned

/ Pd/CaCOs

/PhSOrH

0F F

/

[02S3] 4.40 g (12.0 mmol) of I-butoxy-2, 3-difluoro-4-(4-

pentylcyclohexylethynyl)benzene in 50 ml ofTHF are hydro-

genated at room temperature and atmospheric pressure for a

few minutes in the presence of Pd(5%)/CaCOs (lead-poi-soned Lindlar catalyst). The reaction solution is filtered and

concentrated to dryness.

[02S4] The residue is taken up in 25 ml of toluene and

refluxed for 20 h together with 811 mg (4.94 mmol) of ben-zenesulfinic acid sodium salt and 6 ml of I N hydrochloricacid. The batch is diluted with MTBE and washed succes-sively with water, sat. sodium hydrogencarbonate solutionand sat. sodium chloride solution. The solution is dried usingsodium sulfate and concentrated to dryness. The residue ispurified by column chromatography (SIOn, n-heptane:I-chlorobutane=4: I). The further purification is carried out byrecrystallization from ethanol and n-heptane, giving I-bu-toxy-2, 3-difluoro-4-[(E)-2-(4-pentylcyclohexyl)vinyl] ben-zene ("CVY-5-04") as a colourless solid.

Phase sequence: C 54 N 74 I;

cl.p.=78' C.;

[02S5] AE=—6.0;An=0. 1345 andyt=138 mPa s.[02S6] 'H-NMR (300 MHz, CHCls): 6=7.07-6.99 (m, I H,H, ), 6.70-6.62 (m, IH, H, ), 638 (d, IH, J=15.8 Hz,

H~rrrenrr )) 6 I 3 (dd) I H) J:I5 8 Hz) J:70 Hz) H~rrrenrr )) 4 03(ty 2Hy 6 6 Hzy ~CHnCsH7)y 2 I 3 I 99 (my I Hy H&rr&r

1.87-1.73 (m, 6H, H, , n a), 1.56-1.43 (m, 2H, H, , n a),136-1.11 (m, I IH, H „n,), 1.02-0.86 (m, 8H, H „n,).[02S7] ' F-NMR (282 MHz, CHCls): E=—142.9 (ddd, IF,J=19.1 Hz, J=7.6 Hz, J=1.9 Hz), —159.8 (ddd, IF, J=19.1 Hz,J=7.6 Hz, J=1.9 Hz).[02SS] MS (EI): m/e (%)=354 (53, M ), 156 (100).

Examples 21 TO 29

[02S9] The following compounds were synthesised analo-gously:

Ex. Snuctural formula Acronym Physical data

21 F F

X /

CVY-3-02 C 61 N 66 Icl.p. = 67' C.Ae = —6.4An = I3.1374yt = 99 mPa s

US 2012/0307177 A154

Dec. 6, 2012

-continued

Ex. Structural formula Acronym Physical data

22 F F

/

CVY-3-04 Tg —75 C 21 N611cl.p. = 59' C.Aa = —5.4An = 0.1255

yt = 103 mPa s

23 F F CVY-3-01 C 52 N 561cl.p. = 43' C.Aa = —6.3An = 0.1285

yt = 63 mPa s

24 F F

X /

CCVY-3-03 C 42 SmA 142N 2191cl.p. = 235' C.Aa = —5.7An = 0.1523

25 F F

X /

CCVY-3-02 C 76 SmA 118N2311cl.p. = 247' C.Aa = —6.0An = 0.1595

26

F F

X /

CCVY-5-03 Tg —79 C 34Sm 103 SmA166 N 220 Icl.p. = 236' C.Aa = —5.7An = 0.1595

27

F F

X /

CCVY-5-04 Tg —79 SmC—35 SmA 172 N214 Icl.p. = 236' C.Aa = —5.3An = 0.1465

28

F F

X /

CVY-5-04 Tg —79 C 23SmA (9i N 69 Icl.p. = 73' C.Aa = —s.g

An = 0.1264

yt = 151 mPa s

29 F F

X /

CCVY-IV-02 C 91 SmA (78iN2711cl.p. = 262' C.Aa = —5.6An = 0.1791

US 2012/0307177 A155

Dec. 6, 2012

Example 30

1-[(E)-1,2-Difluoro-2-(4-propylcyclohexyl)vinyl]-4-ethoxy-2, 3-difluorobenzene ("CBY-3-02")

[0290] The compound 1-[(E)-1,2-difluoro-2-(4-propylcy-clohexyl)vinyl]-4-ethoxy-2, 3-difluorobenzene ("CBY-3-02") according to the invention is synthesised as describedbelow.

30.1 Synthesis of 1-chloro-4-propylcyclohexane

[0291]

yltrifluorovinylsilane are metered in. The mixture is warmedslowly and stirred at room temperature for 16 h. Water isadded, and the batch is extracted with MTBE. The aqueousphase is extracted with MTBE, and the combined organicphases are washed with water and saturated sodium chloridesolution. The solution is dried using sodium sulfate and con-centrated under reduced pressure. The residue is digestedwith methanol, and insoluble material is filtered off. Thefiltrate is concentrated under reduced pressure, and the resi-due is purified by column chromatography (SiO~, pentane),giving [(Z)-1,2-difluoro-2-(4-propylcyclohexyl)vinyl]trieth-ylsilane as a colourless oil.

OH SOCtq

[0295]

303 Synthesis of1-KE)-1,2-difluorovinyl)-4-propylcyclohexane

ClTBAF

[0292] 100.0 g (0.70 mol) of 4-propylcyclohexanol are ini-tially introduced in 1200ml of toluene together with 2.7 ml ofDMF, and the mixture is heated to reflux. 255 ml (3.52 mol)of thionyl chloride are carefully metered in, and the batch isheated for a further 4 h. After cooling, the mixture is added towater, and the organic phase is separated off. The aqueousphase is extracted with toluene, and the combined organicphases are washed with water and saturated sodium chloridesolution. The solution is dried using sodium sulfate and con-centrated to dryness. The crude product is purified by columnchromatography (SiO~, n-heptane), giving 1-chloro-4-propy-lcyclohexane as a colourless liquid.

30.2 Synthesis of [(Z)-1,2-difluoro-2-(4-propylcyclo-hexyl) vinyl]tri ethyl silane

[0293] The starting material triethyltrifluorovinylsilane issynthesised as described in the literature [S.A. Fontana, C. R.Davis, Y.-B. He, D. J. Burton, Tetrahedron 1996, 52, 37-44].

Cl

[0296] 34.6 g (0.11 mol) of [(Z)-1,2-difluoro-2-(4-propyl-cyclohexyl)vinyl]triethylsilane are refluxed for 20 h in 900 mlof THF together with 45 ml of water and 160 ml of TBAF(0.16mol, 1 M soln. in THF). The batch is diluted with MTBEand washed a number of times with water. The aqueousphases are extracted with MTBE, and the combined organicphases are washed with water and saturated sodium chloridesolution. The solution is dried using sodium sulfate and con-centrated under reduced pressure. The residue is purified bycolumn chromatography (SiO~, pentane), giving 1-((E)-1,2-difluorovinyl)-4-propylcyclohexane as a colourless oil.

30.4 Synthesis of 1-((Z)-1,2-difluoro-2-iodovinyl)-4-propylcyclohexane

[0297]

Li1. t-BuLi

2. IpH

[0294] 74.1 g (0.28 mol) of 4,4'-di-tert-butylbiphenyl areinitially introduced in 1000 ml of THF in an argon atmo-

sphere, and 1.6 g (0.23 mol) of lithium (granules) are added atO' C.After 5 h, the blue solution is cooled to —78' C., and 40.6g (0.25 mol) of 1-chloro-4-propylcyclohexane are added.After 30 min at this temperature, 49.6 g (0.25 mol) of trieth-

[0298] 7.0 g (263 mmol) of 1-KE)-1,2-difluorovinyl)-4-propylcyclohexane are initially introduced in 150 ml of THFat —55' C., and 20.5 ml (30.2 mmol, 15% soln. in n-pentane)of t-BuLi are metered in. After 2 h at this temperature, asolution of 7.67 g (30.0 mmol) of iodine in 50 ml of THF isadded dropwise. The mixture is slowly warmed to O' C., and

US 2012/0307177 A156

Dec. 6, 2012

water is added. The batch is extracted with MTBE, and theorganic phase is washed with water and saturated sodiumchloride solution. The solution is dried using sodium sulfateand concentrated to dryness. The residue is purified by col-umn chromatography (SIOz, pentane), giving 1-((Z)-1,2-dif-Iuoro-2-iodovinyl)-4-propylcyclohexane as a pale-violet oil.

MIXTURE EXAMPLES I TO 4

[0305] Mixtures M-I to M-4 having the following compo-sitions are prepared and investigated with respect to their

properties.

30.5 Synthesis of I-[(E)-1,2-difluoro-2-(4-propylcy-clohexyl)vinyl]-4-ethoxy-2, 3-difluorobenzene

O'CBY-3-02")

[0299]

[0306]

MIXTURE EXAMPLE I

Composition

Compound Concentration

No. Abbreviation /% by weight

F F

X /F

Pd(PPhs14

NazCOs

toluene/EtOH/water

F F

X /

1

2

3

46

6

7

8

910

PBY-3-02CY-3-04CY-6-04CCY-2-02CCY-3-02CCY-6-02CCY-2-1CCY-3-1CC-3-4CP-6-3

20.09.69.69.69.69.66.46.46.4

12.8

100.0

[0300] 630 g (20.1 mmol) of I-KZ)-1,2-difluoro-2-iodovi-nyl)-4-propylcyclohexane and 4.86 g (24.1 mmol) of 2,3-difluoro-4-ethoxybenzeneboronic acid are refluxed for 19 htogether with 1.16g (1.0mmol) oftetraki striphenylpalladium

(0) and 20 ml (20 mmol) of sodium carbonate solution (2 M)in 90 ml of ethanol/toluene (2:I). Water is added, and thebatch is extracted with MTBE. The aqueous phase isextracted with MTBE, and the combined organic phases arewashed with water. The solution is dried using sodium sulfate

and concentrated to dryness. The residue is purified by col-umn chromatography (SIOz, n-heptane: I -chlorobutane=4: I).The further purification is carried out by recrystallisationfrom n-heptane, giving 1-[(E)-1,2-difluoro-2-(4-propylcy-clohexyl)vinyl]-4-ethoxy-2, 3-difluorobenzene as a colour-less solid (m.p. 60' C.).Phase sequence: C 60 N 64 I;

cl.p.=59' C.;

[0301] AE=—6.5;An=0. 1169 and

yt=106 mPa s.[0302] 'H-NMR (400 MHz, CHCls): 6=7.11-7.06 (m, I H,H /), 6.77-6.71 (m, IH, H /), 4.14 (q, 2H, J=7.2 Hz,

OCHzCHs)) 2 8 I 2 64 (m) IH) Ha//v/ )) I 89 I 80 (m) 4H)H, , n, ), 1.63-1.43 (m, 5H, H, , n, ), 138-1.16 (m, 5H,H /,~„,), 1.07-0.95 (m, 2H, H /,~„,), 0.89 (t, 3H, J=7.2 Hz,

[0303] ' F-NMR (376 MHz, CHCls): f1=—135.0 to —135.2(my IFy Fa&&/ )y I 52 0 (dddy IHy J:13I Hzy J:126 Hzy J:4 9Hz)F~//renv/ ))1550(ddd) IH)J:131HZ)J:301HZ)J:214Hz)F~//renv/ ))1550(ddd) IH)J:131HZ)J:301HZ)J:214Hz) F~//renv/ )) I 58 9 (ddd) IH) J:2I 4 Hz) J:7 5 Hz) J:2 4

[0304] MS (EI): m/e (%)=344 (100, M ).

Physical properties

T(N, Ii =

n, (20' C., 689 nmi =

An(20' C., 689 nmi =

Ae(20' C., 1 kHzi =

71(20' C 1 =

71.6' C.1.6910.111

—3.9161 mPa s

[0307] This mixture is highly suitable for use in VA dis-

plays.

Comparison Test

Test

[0310] In the comparison test, this mixture is introducedinto a VHR test cell. However, it is investigated here with

respect to its stability to a (new) backlight for LCDs which

utilises LEDs as light sources. The HR (VHR) (voltage hold-

ing ratio) in the cell after 10 min at 100' C. is 92% as in thecomparison test. After irradiation with the LED backlight for1000 h, however, the HR is still 86% and is thus significantly

better.

[0308] This mixture is introduced into a test cell for deter-

mination of the VHR and investigated with respect to its

stability to a backlight which is customary for LCDs (coldcathode fluorescent lamp/CCFL backlight) as describedabove.

[0309] The HR (VHR) (voltage holding ratio) in the cellafter 5 min in the oven at 100' C. (HRt«) is 92%. Afterirradiation with the CCFL backlight for 1000 h, the HR is77%.

US 2012/0307177 A157

Dec. 6, 2012

[0311]

MIXTURE EXAMPLE 2 [0314] This mixture is highly suitable for use in VA dis-plays. It is adequately stable to lighting with an LED back-light.

Composition

Compound

No. Abbreviation

Concentration

/% by weight

[0315]

MIXTURE EXAMPLE 4

I23466

789

10

CBY-3-02CY-6-02CCY-3-02CLY-2-04CLY-3-02CLY-3-03CPY-2-02CPY-3-02CC-3-VCC-3-Vl

19.06.02.04.04.04.08.09.0

34.011.0

100.0

Physical properties

T(N, Ii =

n, (20' C. , 689 nmi =An(20' C., 689 nmi =er(20' C., I kHzi =Ae(20' C. , I kHzi =71(20' C l =kt(20' Cd =ks(20' Cd =Vo(20' Cd =

81' C.1.67360.09666.3

—3.093 mPa s

13.9 pN16.7 pN2.61 V

MIXTURE EXAMPLE 3

[0312] This mixture is highly suitable for use in VA dis-plays. It is adequately stable to lighting with an LED back-light.

Composition

Compound

I23466789

10ll

CVY-3-02CY-3-02CY-6-02CCY-3-02CCY-4-02CLY-2-04CLY-3-02CLY-3-03CPY-3-02CC-3-VCC-3-Vl

Physical properties

T(N, Ii =

n, (20' C., 689 nmi =An(20' C., 689 nmi =er(20' C. , I kHzi =Ae(20' C., I kHzi =71(20' C l =kt(20' Cd =ks(20' Cd =Vo(20' Cd =

No. Abbreviation

Concentration

/% by weight

22.03.06.08.03.04.04.04.06.0

33.08.0

100.0

80' C.1.67180.09437.0

—3.6108 mPa s

14.6 pN16.6 pN2.29 V

[0313]

Composition

I23466789

10

CVY-3-02CY-6-02CCY-3-02CLY-2-04CLY-3-02CLY-3-03CPY-2-02CPY-3-02CC-3-VCC-3-Vl

Physical properties

Compound

No. Abbreviation

Concentration

/% by weight

19.06.06.04.04.04.06.08.0

38.07.0

100.0

[0316] This mixture is highly suitable for use in VA dis-plays. It is adequately stable to lighting with an LED back-light.

1. Electro-optical display based on a liquid-crystal cell,characterised in that it contains

as dielectric, a liquid-crystalline medium having negativedielectric anisotropy and

includes a backlight which only emits light having a wave-lenlnh of 420 nm or more or

has, between the liquid-crystal layer and the backlight, acut-off filter which only allows light having a wave-lenlnh of 420 nm or more to pass through.

2. Display according to claim 1, characterised in that theliquidcrystalline medium having negative dielectric anisot-

ropy comprises

a) a (first) dielectrically negative component (componentA), which consists of one or more compounds of theformula I

T(N, Ii =

n, (20' C. , 689 nmi =An(20' C., 689 nmi =er(20' C., I kHzi =Ae(20' C. , I kHzi =71(20' C l =kt(20' Cd =ks(20' Cd =Vo(20' Cd =

82' C.1.67690.09786.6

—3.188 mPa s

14.6 pN16.4 pN2.43 V

F F

R" A" Z" A' Z' Z" A" Rtzl1l / l1l

US 2012/0307177 A158

Dec. 6, 2012

in whichR" and R' each, independently of one another, denote H,

an unsubstituted alkyl or alkenyl radical having up to 15C atoms, where, in addition, one or more CH2 groups inthese radicals may be replaced by 0, S &.3-

-continued

C—C, CF2~, ~ CF2, CO~ or0~0 in such a way that 0 atoms are not linkeddirectly to one another,

A12

and, if present,F F

A11 A"

each, independently of one another, denote Z' denotes MF CF, MF CH, MH CFMH CH or M C

Z" and Z', ifpresent, each, independently ofone another,

denote CH2 CH2, ~H CH, C CMH2M, MMH2, COW

CO ) MF2 0 ) M CF2 ) MF2CF2 or a single bond,

m and n, independently ofone another, denote 0, I or 2, and

(m+n) preferably denotes 0, I or 2,

and

b) a (second) dielectrically negative component (compo-nent B).

3. Display according to claim 2, characterised in that thesecond dielectrically negative component (component B) ofthe liquid-crystalline medium consists of one or more com-

pounds selected from the group of the formulae II, III and IV:

R21 A21 z21 A22 Z22 A Z23 A24 R22r 5

III

R' A' Z' A Z A Z A R1 0

IV

R41 A41 z41 A42 z42 A4' Z4' A44 R42I II

US 2012/0307177 A159

Dec. 6, 2012

in whichR ' and R each, independently of one another, denote H,

an unsubstituted alkyl or alkenyl radical having up to 15C atoms, where, in addition, one or more CH2 groups inthese radicals may be replaced by 0, S

-continued

one of the rings

C—C, CF2~, ~ CF2, CO~ or0~0 in such a way that 0 atoms are not linkeddirectly to one another,

R ', R, R ' and R each, independently of one another,have one of the meanings given for R ' and R

one of the rings

A"

present denotes

to A'4

A21 to A24

FF F

FF F

present denotes FF F

FF F

L ' and L, independently of one another, denoteC(X ) and one of L and L alternatively also

denotes NX denotes F, Cl, OCF3, CF3, CH3, CH2F, CHF2,and the other rings, if present, each, independently of one

another, denote

and the others, ifpresent, each, independently ofone another,denote

c3-

L31 L32

/

whereL ' and L, independently of one another, denote

C(X ) and one of L ' and L alternatively alsodenotes N, and

US 2012/0307177 A160

Dec. 6, 2012

X denotes F, Cl, OCF» CF» CH» CH2F, CHF2,-continuedF F

together optionally also denote a single bond, one of the rings

A41 A44

present denotes

and the others, ifpresent, each, independently ofone another,denote

F F F F

//

F F

//

F F

F F

F F

&'3—-C.~

0

/ X, /

F F

/ X / F F

A41 z41

/ X /0 F

/ X /

together optionally also denote a single bond,Z 'toZ"

Z ' to Z each, independently of one another, have one ofthe meanings given for Z" in claim 2,

1 and o each, independently of one another, denote 0 or 1,r and s each, independently of one another, denote 0 or 1,

andt and u each, independently of one another, denote 0 or 1.4. Display according to claim 3, characterised in that the

liquid-crystalline medium comprisesc) a dielectrically neutral component (component C),

which consists ofone ormore compounds ofthe formulaV

V

R' A' Z' A Z A Z A RP

US 2012/0307177 A161

Dec. 6, 2012

in which

R ' and R each, independently of one another, have oneof the meanings given for R" and R',

-continuedF

A" to A'4

each, independently of one another, denote

&'3—

Z ' to Z each, independently of one another, denoteMH2MH2 ) CH CH M C MH20 ~ CH2, CO~, O~OMF2M OMF2 MF2 CF2 or a singlebond and

p and q each, independently of one another, denote 0 or l.5. Display according to claim 2, characterised in that the

liquid-crystalline medium comprisesd) a chiral component (component D), which consists of

one or more chiral compounds.6. Display according to claim 3, characterised in that the

second dielectrically negative component (component B) ofthe liquid-crystalline medium comprises one or more com-pounds of the formula II according to claim 3.

7. Display according to claim 2, characterised in that theliquid-crystalline medium comprises one or more com-pounds selected from the group of the compounds of theformulae I-l to I-5:

F

Rl 1 Al 1 Z 1 1 A12

F F

R" A" zl 1

F FI-2

F

Rl 1 Al 1 Z 1 1 A12

F FI-3

Rl 1 Al 1 Z 1 1 A12

F FI-4

F F

Rl 1 A 1 1 Z" . A12 C=C

in which the variables have the meanings given in claim 2.

US 2012/0307177 A162

Dec. 6, 2012

Rl 1

F F F

S. Display according to claim 2, characterised in that theliquid-crystalline medium comprises one or more com-pounds selected from the group of the compounds of theformulae I-I a to I- Ig:

-continued

/ X /

/ X /

I- Ig

Rl 1

Rl 1

Rl 1

F F

/

/

/ X /

F F F

F F

F F

I- Ib

I-I c

I-I e

in which the variables have the meanings given in claim 2.9. Display according to claim 4, characterised in that it

contains a medium which comprises

2-80% by weight of one or more compounds of the formula

I, and

2-80% by weight of one or more compounds of the formulaII, and/or

2-80% by weight of one or more compounds of the formulaIII, and/or

2-80% by weight of one or more compounds of the formulaIV, and

2-80% by weight of one or more compounds of the formula

V,

where the total content of all compounds of the formulae Ito V in the medium is 100% by weight or less.

10.Display according to claim 1,characterised in that it hasan active-matrix addressing device.

11.Display according to claim 1, characterised in that it isbased on the VA, ECB, PSVA, FFS or IPS effect.

12.Display according to claim 1,characterised in that it hasan LED backlight and/or a cut-off filter between the backlightand the liquid-crystal cell.

13.Display according to claim 1,characterised in that it hasa backlight and in that the light from the backlight whichreaches the liquid-crystal medium does not comprise anylight having a wavelength of less than 400 nm.

14. Liquid-crystalline medium, characterised in that it hasa composition as defined in claim 4.

15.Use of a liquid-crystalline medium according to claim14 in an electro-optical display.

16. Process for the preparation of a medium according toclaim 14, characterised in that one or more compounds of theformula I are mixed with one or more compounds selectedfrom the group of the compounds of the formulae II, III andIV and/or with one or more compounds of the formula Vand/or one or more further liquid-crystalline compounds and/

or one or more dopants, dyes and/or additives.

17.Compounds of the formula I-l'

Rl 1 A] ] zl 1

F F F

/Z" A" „ R"

in which the parameters have the meanings given in claim2.

US 2012/0307177 A163

Dec. 6, 2012

Rl 1

F F F

1S.Compounds of the formula I-l' according to claim 17selected from the group of the compounds of the formulaeI-la, I-lb and I-Ic:

Rl 1

-continued

F F

I-I c

Rl 1

/

F F F

/

I- Ib

19.Process for the preparation of a compound of the for-

mula I-l' according to claim 17, characterised in that a 1,2-

difluoroethylene halide is reacted with an arylboronic acid in

a cross-coupling.

20. Liquid-crystalline medium, which has a composition as

defined in claim 2.