WO2005095544A1 - Liquid crystal compounds, liquid crystal medium and liquid crystal display - Google Patents

Abstract

The instant invention relates to mesogenic compounds with mesogenic group and one or more bulky end groups which each contain at least two ring elements, where two of these ring elements are linked to a centre atom or to a centre group by a direct bond or via a linking group, preferably of Formula (I) wherein the parameters are as specified in the text. This bulky end group preferably contains two or more rings, which each are bound to one and the same linking atom. The instant invention further relates to mesogenic media, preferably liquid crystal media showing a blue phase and their use in electro-optical light modulation elements and their respective use in displays, as well as to such devices.

Description

Liquid Crystal Compounds, Liquid Crystal Medium and Liquid Crystal Display

Field of the invention

The present invention relates to mesogenic compounds, mesogenic media and to electro-optical displays comprising these mesogenic media as light modulation media, in particular to displays which are operated at a temperature at which the mesogenic modulation media are in an optically isotropic phase, preferably in a blue phase.

Problem to be solved and state of the art

Electro-optical displays and mesogenic light modulation media, which are in the isotropic phase when being operated in the display are described in DE 102 17273 A. Electro-optical displays, and mesogenic light modulation media, which are in the so-called blue phase, when being operated in the display are described in DE 103 13 979.6, which is not yet laid open.

The mesogenic media and displays described in these references provide several significant advantages compared to well-known and widely used displays using liquid crystals in the nematic phase, like for example liquid crystal displays (LCDs) operating in the twisted nematic (TN)-, the super twisted nematic (STN)-, the electrically controlled birefringence (ECB)- mode with its various modifications and the h pjane switching (IPS)-mode. Amongst these advantages are most pronounced their much faster switching times, and significantly wider optical viewing angle.

Whereas, compared to displays using mesogenic media in another liquid crystalline phase, as e.g. in the smectic phase in surface stabilized ferroelectric liquid crystal displays (SSF LCDs), the displays of DE 102 17 273.0 and DE 103 13 979 are much easier to be produced. For example, they do not require a very thin cell gap in the first place and the electro-optical effect is not very sensitive to small variations of the cell gap as well. However, the liquid crystal media described in these mentioned patent applications still require operating voltages, which are not low enough for some applications. Further the operating voltages of these media vary with temperature, and it is generally observed, that at a certain temperature the voltage dramatically increases with increasing temperature. This limits the applicability of liquid crystal media in the blue phase for display applications. A further disadvantage of the liquid crystal media described in these patent applications is their moderate reliability which is insufficient for very demanding applications. This moderate reliability may be for example expressed in terms of the voltage holding ratio parameter (VHR), which in liquid crystal media as described above may be below 90%.

Compounds of the formula

with R³ and/or R⁴ possibly being a terminal benzhydryl group or a terminal substituted benzhydryl group, are generally mentioned in EP 1 262471 A2, however no examples are given.

Some compounds and compositions have been reported which possess a blue phase between the cholesteric phase and the isotropic phase and can usually be observed by optical microscopy. These compounds or compositions for which the blue phases are observed are typically single mesogenic compounds or mixtures showing a high chirality. However, generally the blue phases observed only extend over a very small temperature range , which is typically less than 1 degree centigrade

(Kelvin) wide. In order to operate the novel fast switching display mode of DE 103 13 979.6 the light modulation medium to be used has to be in the blue phase, however. Thus a light modulation medium possessing a blue phase which is as wide as possible is required. Therefore there is a strong need for a modulation medium with a blue phase with a wide phase range, which may be achieved either by an appropriate mixture of mesogenic compounds themselves or, preferably by mixing a host mixture with appropriate mesogenic properties with a single dopant or a mixture of dopants that stabilises the blue phase over a wide temperature range.

Summarizing, there is a need for liquid crystal media, which can be operated in liquid crystal displays which are operated at temperatures where the media is in the blue phase, which provide the following technical improvements:

- a reduced operating voltage,

- a reduced temperature dependency of the operating voltage and - an improved reliability, e.g. VHR.

Present invention

Surprisingly, it now has been found that compounds with a molecular structure comprising of a mesogenic group and at least one bulky end group are suitable to considerably enhance the range of temperatures over which the blue phase is stable or even induce a blue phase in respective mesogenic hosts, which do not show such a phase on their own. Preferably the mesogenic hosts are liquid crystalline hosts. The mesogenic compounds are characterized in that they comprise one or more bulky end groups, which each comprise at least two ring elements, where two of these ring elements are linked to a centre atom or to a centre group by a direct bond or via a linking group and, where two of these ring elements optionally may be linked to each other, either directly or via a linking group, which may be identical to or different from the linking group mentioned. The bulky end group or end groups do each contain at least two ring elements, which are preferably selected from the group of four -, five -, six - or seven -, preferably of five - or six -, membered rings, which are linked by a direct bond or a linking group to a centre atom or to a centre group and which may optionally be linked to each other directly or via a linking group. In a preferred embodiment the compounds according to the present invention are chiral compounds, preferably the bulky end group or, in case there is more than one bulky end group in the molecule, at least one of the bulky end groups is a chiral group, i.e. a group with a chiral centre, preferably a chirally substituted atom and most preferably a chirally substituted C-atom.

Preferably these compounds with a molecular structure consisting of a mesogenic core and at least one bulky end group are of formula I

wherein

MG is a divalent radical of the formula

BG represents either two npnovalent radicals, short MR, each independently of one another, of formula MR-1 or a divalent radical, short DR, preferably selected from the group of formulae DR-1 , DR-2, and DR-3, preferably of formula DR-1 -1 ,

DR-1 IS

DR-1-1 is

R 11 is H, F, CI, Br, I, CN, N0₂, NCS, SF₅ , S0₂CF₃ or alkyl which is straight chain or branched, preferably has 1 to 20 C-atoms, is unsubstituted, mono- or poly-substituted by F, CI, Br, I or CN, and in which one or more non- adjacent CH₂ groups are optionally replaced, in each case independently from one another, by -0-, -S-, -NH-, -NR⁰¹-, -SiR⁰¹R⁰²-, -CO-, -COO-, -OCO-, -OCO-0-, -S- CO-, -CO-S-, -CY¹=CY²- or -C≡C- in such a manner that O and/or S atoms are not linked directly to one another, preferably H, Halogen, n-alkyl, n-alkoxy with 1 to 7 C- atoms preferably 2 to 5 C-atoms, alkenyl, alkenyloxy or alkoxyalkyl with 2 to 7 C-atoms, preferably with 2 to 5 C- atoms or CN, NCS, halogen, preferably F, CI, halogenated alkyl, alkenyl or alkoxy, preferably mono-, di- or oligo-fluorinated alkyl, alkenyl or alkoxy, especially preferred CF₃, OCF₂H or OCF₃, or R¹¹ denotes PG-SG,

R 12 has one of the meanings given for R¹¹ and for X¹³-MR or

R¹³ to R¹⁵ have, independently of each other, one of the meanings given for R 11

R ^■>0^U1¹ and R 02 are, independently of each other, H or alkyl with 1 to 12 C-atoms,

R is H or alkyl preferably H or alkyl with 1 to 10 C-atoms,

PG is a polymerisable or reactive group,

SG is a spacer group or a single bond, and

are, independently of each other, an aromatic and/or alicyclic ring, or a group comprising two or more fused aromatic or alicyclic rings, wherein these rings optionally contain one or more hetero atoms selected from N, O and/or S, and are optionally mono- or polysubstituted by R,

Z° is C or N,

Z¹¹ to Z¹⁶ are, independently of each other, -0-, -S-, -CO-, -CO-0-,

-0-C0-, -S-CO-, -CO-S-, -0-CO-0-, -CO-NR⁰¹-, -NR⁰¹-CO-, -OCH2-, -CH₂O-, -SCH₂-, -CH₂S-, -CF₂0-, -OCF2-, -CF₂S-, -SCF-, -CH2CH2- -, -CF₂CH₂-, -CH₂CF₂-, -CF₂CF₂-, -CH=N-, -N=CH-, -N=N-, -CH=CR⁰¹-,

-CY⁰¹=CY⁰²-, -C≡C-, -(CH₂) ₄-, -CH=CH-CO-0-, -0-CO-CH=CH- or a single bond,

Y⁰¹ and Y⁰² are, independently of each other, F, CI or CN, and alternatively one of them may be H,

X¹¹ to X¹⁵ have, independently of each other, one of the meanings given for Z¹¹ and preferably are -0-, -C0-0-, -0-CO-, -CF₂O-, -OCF₂- a single bond and X¹² alternatively may be -CG-Z¹¹- or -Z¹¹-CG-,

Y¹¹ has one of the meanings given for Z¹¹ or is -(CH₂)3- or

-CH₂-CH(CH₃)- and preferably is a single bond -S-, -O- -CO-O-, -O-CO-, -O-CO- or -CH=CH-, most preferably -0-, a single bond, -CH=CH- or -S-,

n is 0 or 1

m is 2 in case BG is MR and 1 in case BG is DR, o is 1 or 2,

n + o is 2,

p and q are, independently of each other, 0 or 1 ,

p + q is preferably 0 or 1 , preferably 0,

r in case Z° is C is 1 and in case Z° is N is 0,

s, t and u are, independently of each other, 0, 1 or 2, preferably 0 or 1 , preferably 0, except in DR-2, where s is 1 or 2, preferably 1 and in DR-3, where, s and t are, independently of each other, 1 or 2, preferably 1.

Particularly preferred are compounds of formula I, wherein

Z¹¹ is -0-, -CO-0-, -OCO-, -0-CO-0-, -CH₂-0-, -0-CH₂-, -CF₂-0-, -0-CF₂-, -C≡C- or -CH=CH-, most preferably -CO-O- or -O-CO- or -O- and/or

Z¹¹ is different from a single bond and/or ring A¹¹ is phenylene that is optionally substituted by one or more groups R and/or

R is PG-SG- and/or

R is alkyl or alkoxy with 1 to 12, preferably 1 to 8 C-atoms, or alkenyl, alkenyloxy or alkynyl with 2 to 12, preferably 2 to 7 C-atoms and/or - SG is alkylene with 1 to 12 C atoms which is optionally mono- or polysubstituted by F and wherein one or more non-adjacent CH₂ may be replaced, in each case independently from one another, by -0-, -CH=CH- or -C≡C-, and that is linked to a ring, preferably to ring A¹ via a group selected from -0-, -CO-O-, -O-CO-, -0-CO-O- and a single bond and/or

SG is a single bond and/or X¹² is -CO-0-CG-, -0-CO-CG-, -0-CF₂-CG-, -CF₂-0-CG- and/or preferably CG is

In a preferred embodiment rings A¹¹ to A¹³ are, independently of each other, an aromatic or alicyclic ring, preferably a 5-, 6- or 7-membered ring, or a group comprising two or more, preferably two or three, fused aromatic or alicyclic rings, wherein these rings optionally contain one or more hetero atoms selected from N, O and/or S, and are optionally mono- or polysubstituted with L, wherein L is F, CI, Br, CN, OH, N0₂, and/or an alkyl, alkoxy, alkylcarbonyl or alkoxycarbonyl group with 1 to 12 C atoms, wherein one or more H atoms are optionally replaced by F or CI.

L is preferably F, CI, CN, OH, N0₂, CH₃, C₂H₅, OCH₃, OC₂H₅, COCH_3> COC₂H₅, COOCH3, COOC2H5, CF₃, OCF3, OCHF2 or OC2F5, in particular F, CI, CN, CH₃₎ C₂H₅. OCH3, COCH3 or OCF₃, most preferably F, Ci, CH₃,

In a preferred embodiment rings B¹¹ and B¹² are, independently of each other, phenylene, naphthalenediyl, cyclohexanediyl, which optionally may be substituted, preferably by halogen, preferably by F, or by alkyl, preferably by n-alkyl, preferably by methyl.

In a further preferred embodiment rings C¹¹ to C¹⁴ are, independently of each other, phenylene, cyclohexanediyl or naphthalenediyl, which optionally may be substituted, preferably by halogen, preferably by F, or by alkyl, preferably by n-alkyl, preferably by methyl.

Preferred rings A¹¹ to A¹³ , B¹¹, B¹² and C¹¹ to C¹⁴ are for example furan, pyrrol, thiophene, oxazole, thiazole, thiadiazole, imidazole, phenylene, cyclohexylene, cyclohexenylene, pyridine, pyrimidine, pyrazine, azulene, indane, naphthalene, tetrahydronaphthalene, decahydronaphthalene, tetrahydropyrane, anthracene, phenanthrene and fluorene. Particularly preferably one or more of these rings A¹¹ to A¹³ , B¹¹, B¹² and C¹¹ to C¹⁴ is, respectively are, selected from furane-2,5-diyl, thiophene-2,5- diyl, thienothiophene-2,5-diyl, dithienothiophene-2,6-diyl, pyrrol-2,5-diyl, 1 ,4-phenylene, azulene-2,6-diyl, pyridine-2,5-diyl, pyrimidine-2,5-diyl, naρhthalene-2,6-diyl, 1 ,2,3,4-tetrahydro-naphthalene-2,6-diyl, indane-2,5- diyl, or 1 ,4-cyclohexylene wherein one or two non-adjacent CH₂ groups are optionally replaced by O and/or S, wherein these groups are unsubstituted, mono- or polysubstituted by L as defined above.

Preferably

wherein

R is alkyl with 1 to 12 C-atoms, preferably with 1 to 7 C- atoms, or alkenyl or alkynyl with 2 to 12 C-atoms, preferably with 2 to 7 C-atoms, in both of which one or more non-adjacent -CH₂- groups, not adjacent to the phenyl ring, may be replaced by -O- and/or -CH=CH- and/or one or more H-atoms may be replaced by halogen, preferably by F,

or their mirror images.

and

independently of each other, have one of the meanings

wherein

R' has the meaning given for R above and preferably is alkyl, preferably methyl, ethyl or propyl

and/or preferably

Most preferably

wherein

R has the meaning given above and preferably is alkyl, preferably methyl, ethyl or propyl, preferably methyl.

In a preferred embodiment of the present invention the group

contains only monocyclic rings A¹¹ to A¹³. Very preferably this is a group with one or two 5- and/or 6-membered rings.

Preferred sub formulae for this group are listed below. For reasons of simplicity, Phe in these groups is 1 ,4-phenylene, PheL is a 1 ,4-phenylene group which is substituted by 1 to 4 groups L as defined above, Cyc is 1 ,4- cyclohexylene, Pyd is pyridine-2,5-diyl and Pyr is pyrimidine-2,5-diyl. The following list of preferred groups is comprising the sub formulae 1-1 to I-20 as well as their mirror images,

-Phe- 1-1

-Pyd- I-2 -Pyr- I-3

-PheL- I-4

-Cyc- I -5

-Phe-Z-Cyc- I-6

-Cyc-Z-Cyc- I-7 -PheL-Cyc- I-8

-Phe-Z-Phe- I-9

-Phe-Z-Pyd- 1-10

-Pyd-Z-Phe- 1-11

-Phe-Z-Pyr- 1-12 -Pyr-Z-Phe- 1-13

-PheL-Z-Phe- 1-14

-PheL-Z-Pyd- 1-15

-PheL-Z-Pyr- 1-16

-Pyr-Z-Pyd- 1-17 -Pyd-Z-Pyd- 1-18

-Pyr-Z-Pyr- 1-19

-PheL-Z-PheL- I-20

In these preferred groups Z has the meaning of Z¹¹ as given in formula I. Preferably Z is -COO-, -OCO-, -CH₂CH₂-, -C≡C- or a single bond. Very preferably the group

is selected from the following formulae la to Ih and their mirror images

wherein L has the meaning given above, R¹ has the meaning given for R in formula I and r is 0, 1 , 2, 3 or 4, preferably 0, 1 or 2.

in these preferred formulae is very preferably

'

with L having each independently one of the meanings given above.

Especially preferred compounds of formula I comprise at least 2 one group — A V- wherein r is 1.

Further preferred compounds of formula I comprise at least

two groups —X — wherein r is 1 and/or at least one group

wherein r is 2.

preferably is

wherein the 1 ,4-phenylene rings may optionally be substituted by R, preferably by alkyl, preferably by methyl,

35 and/or by alkoxy and/or by halogen, preferably F. More preferably

35

35

wherein R has the meaning given above and preferably is alkyl, preferably with 1 to 6 C-atoms, preferably n-alkyl, wherein one or more non-adjacent - CH₂- groups optionally may be replaced by -O- and/or by -CH=CH- and/ or one or more H-atoms may be replaced by halogen, preferably by F.

Preferably DR-1-1 is a divalent radical selected from the following group of formulae

wherein the parameters have the meaning given above. Preferably

t eanings

preferably for

In a preferred embodiment DR-1-1 is selected from the following group of formulae

In a preferred embodiment

BG is a monovalent radical (MR) selected from the following group of formulae

In a preferred embodiment R¹² has one of the meanings given for "BG" or is H, -CF₃, -C≡C-H,

wherein R' has the meaning given above and preferably is H, CH₃ or C₂H₅

In a preferred embodiment

m is selected from the group of formulae

30

35

30

35 In particular

may be racemic, i.e.

or chiral, i.e.

or chiral i.e.

or chiral, i.e.

35 An alkyl or an alkoxy radical, i.e. an alkyl where the terminal CH group is replaced by -0-, in this application may be straight-chain or branched. It is preferably straight-chain, has 1, 2, 3, 4, 5, 6, 7 or 8 carbon atoms and accordingly is preferably methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, ethoxy, propoxy, butoxy, pentoxy, hexoxy, heptoxy, or octoxy, furthermore methyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, nonoxy, decoxy, undecoxy, dodecoxy, tridecoxy or tetradecoxy, for example.

Oxaalkyl, i.e. an alkyl group in which one non-terminal CH₂ group is replaced by -0-, is preferably straight-chain 2-oxapropyl (= methoxy- methyl), 2- (= ethoxymethyl) or 3-oxabutyl (= 2-methoxyethyl), 2-, 3-, or 4- oxapentyl, 2-, 3-, 4-, or 5-oxahexyl, 2-, 3-, 4-, 5-, or 6-oxaheptyl, 2-, 3-, 4-, 5-, 6- or 7-oxaoctyl, 2-, 3-, 4-, 5-, 6-, 7- or 8-oxanonyl or 2-, 3-, 4-, 5-, 6-,7-, 8- or 9-oxadecyl, for example.

An alkenyl group, i.e. an alkyl group wherein one or more CH₂ groups are replaced by -CH=CH-, may be straight-chain or branched. It is preferably straight-chain, has 2 to 10 C atoms and accordingly is preferably vinyl, prop-1-, or prop-2-enyl, but-1-, 2- or but-3-enyl, pent-1-, 2-, 3- or pent-

4-enyl, hex-1-, 2-, 3-, 4- or hex-5-enyl, hept-1-, 2-, 3-, 4-, 5- or hept-6-enyl, oct-1-, 2-, 3-, 4-, 5-, 6- or oct-7-enyl, non-1-, 2-, 3-, 4-, 5-, 6-, 7- or non- 8-enyl, dec-1-, 2-, 3-, 4-, 5-, 6-, 7-, 8- or dec-9-enyl.

Especially preferred alkenyl groups are C₂-C7-I E-alkenyl, C4-C7-3E- alkenyl, C₅-C₇-4-alkenyl, C₆-C₇-5-alkenyl and C₇-6-alkenyl, in particular C₂-C₇-I E-alkenyl, C -C₇-3E-alkenyl and C₅-C₇-4-alkenyl. Examples for particularly preferred alkenyl groups are vinyl, 1E-propenyl, 1E-butenyl, 1E-pentenyl, 1E-hexenyl, 1E-heptenyl, 3-butenyl, 3E-pentenyl, 3E-hexenyl, 3E-heptenyl, 4-pentenyl, 4Z-hexenyl, 4E-hexenyl, 4Z-heptenyl, 5-hexenyl, 6-heptenyl and the like. Groups having up to 5 C atoms are generally preferred.

In an alkyl group, wherein one CH₂ group is replaced by -O- and one by -CO-, these radicals are preferably neighboured. Accordingly these radicals together form a carbonyloxy group -CO-O- or an oxycarbonyl group -O-CO-. Preferably such an alkyl group is straight-chain and has 2 to 6 C atoms.

It is accordingly preferably acetyloxy, propionyloxy, butyryloxy, pentanoyloxy, hexanoyloxy, acetyloxymethyl, propionyloxymethyl, butyryloxymethyl, pentanoyloxymethyl, 2-acetyioxyethyl, 2-propionyloxy- ethyl, 2-butyryloxyethyl, 3-acetyloxypropyl, 3-propionyloxypropyl, 4-acetyloxybutyl, methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, butoxycarbonyl, pentoxycarbonyl, methoxycarbonylmethyl, ethoxy- carbonylmethyl, propoxycarbonylmethyl, butoxycarbonylmethyl, 2-(methoxycarbonyl)ethyl, 2-(ethoxycarbonyl)ethyl, 2-(propoxy- carbonyl)ethyl, 3-(methoxycarbonyl)propyl, 3-(ethoxycarbonyl)propyl, 4-(methoxycarbonyl)-butyl.

An alkyl group wherein two or more CH₂ groups are replaced by -O- and/or -COO-, it can be straight-chain or branched. It is preferably straight-chain and has 3 to 12 C atoms. Accordingly it is preferably bis-carboxy-methyl, 2,2-bis-carboxy-ethyl, 3,3-bis-carboxy-propyl, 4,4-bis-carboxy-butyl, 5,5-bis-carboxy-pentyl, 6,6-bis-carboxy-hexyl, 7,7-bis-carboxy-heptyl, 8,8-bis-carboxy-octyl, 9,9-bis-carboxy-nonyl, 10,10-bis-carboxy-decyl, bis- (methoxycarbonyl)-methyl, 2,2-bis-(methoxycarbonyl)-ethyl, 3,3-bis- (methoxycarbonyl)-propyl, 4,4-bis-(methoxycarbonyl)-butyl, 5,5-bis- (methoxycarbonyl)-pentyl, 6,6-bis-(methoxycarbonyl)-hexyl, 7,7-bis- (methoxycarbonyl)-heptyl, 8,8-bis-(methoxycarbonyl)-octyl, bis- (ethoxycarbonyl)-methyl, 2,2-bis-(ethoxycarbonyl)-ethyl, 3,3-bis- (ethoxycarbonyl)-propyl, 4,4-bis-(ethoxycarbonyl)-butyl, 5,5-bis- (ethoxycarbonyl)-hexyl.

A alkyl or alkenyl group that is monosubstituted by CN or CF₃ is preferably straight-chain. The substitution by CN or CF₃ can be in any desired position.

An alkyl or alkenyl group that is at least monosubstituted by halogen, it is preferably straight-chain. Halogen is preferably F or CI, in case of multiple substitution preferably F. The resulting groups include also perfluorinated groups. In case of monosubstitution the F or CI substituent can be in any desired position, but is preferably in ω-position. Examples for especially preferred straight-chain groups with a terminal F substituent are fluormethyl, 2-fluorethyl, 3-fluorpropyl, 4-fluorbutyl, 5-fluorpentyl, 6-fluorhexyI and 7-fluorheptyl. Other positions of F are, however, not excluded.

Halogen means F, CI, Br and I and is preferably F or CI, most preferably F.

Each of R¹¹ to R¹⁵ may be a polar or a non-polar group. In case of a polar group, it is preferably selected from CN, SF₅, halogen, OCH₃, SCN, COR⁵, COOR⁵ or a mono- oligo- or polyfluorinated alkyl or alkoxy group with 1 to 4 C atoms. R⁵ is optionally fluorinated alkyl with 1 to 4, preferably 1 to 3 C atoms. Especially preferred polar groups are selected of F, CI, CN, OCH₃, COCH₃, COC2H5, COOCH3, COOC2H5, CF₃, CHF≥, CH₂F, OCF_3> OCHF≥, OCH₂F, C₂F₅ and OC2F5, in particular F, CI, CN, CF₃, OCHF₂ and OCF₃. In case of a non-polar group, it is preferably alkyl with up to 15 C atoms or alkoxy with 2 to 15 C atoms.

Each of R¹¹ to R¹⁵ may be an achiral or a chiral group. In case of a chiral group it is preferably of formula I*:

*

-Q¹-CH-Q²

I

Q³ ,*

wherein

Q¹ is an alkylene or alkylene-oxy group with 1 to 9 C atoms or a single bond,

Q² is an alkyl or alkoxy group with 1 to 10 C atoms which may be unsubstituted, mono- or polysubstituted by F, CI, Br or CN, it being also possible for one or more non-adjacent CH₂ groups to be replaced, in each case independently from one another, by -C≡C-, -0-, -S-, -NH-, -N(CH₃)-, -CO-, -COO-, -OCO-, -OCO-O-, -S-CO- or -CO-S- in such a manner that oxygen atoms are not linked directly to one another, Q³ is F, CI, Br, CN or an alkyl or alkoxy group as defined for Q² but being different from Q².

In case Q¹ in formula I^* is an alkylene-oxy group, the O atom is preferably adjacent to the chiral C atom.

Preferred chiral groups of formula I* are 2-alkyl, 2-alkoxy, 2-methylalkyl, 2- methylalkoxy, 2-fluoroalkyl, 2-fluoroalkoxy, 2-(2-ethin)-alkyl, 2-(2-ethin)-alkoxy, 1,1,1 -trif luoro-2-alkyl and 1,1,1 -trif luoro-2-alkoxy.

Particularly preferred chiral groups I* are 2-butyl (=1-methylpropyl), 2- methylbutyl, 2-methylpentyl, 3-methylpentyl, 2-ethylhexyl, 2-propylpentyl, in particular 2-methylbutyl, 2-methylbutoxy, 2-methylpentoxy, 3- methylpentoxy, 2-ethylhexoxy, 1-methylhexoxy, 2-octyloxy, 2-oxa-3- methylbutyl, 3-oxa-4-methylpentyl, 4-methylhexyl, 2-hexyl, 2-octyl, 2-nonyl, 2-decyl, 2-dodecyl, 6-methoxyoctoxy, 6-methyloctoxy, 6- methyloctanoyloxy, 5-methylheptyloxycarbonyl, 2-methylbutyryloxy, 3- methylvaleroyloxy, 4-methylhexanoyloxy, 2-chlorpropionyloxy, 2-chloro-3- methylbutyryloxy, 2-chloro-4-methylvaleryloxy, 2-chloro-3-methylvaleryloxy, 2-methyl-3-oxapentyl, 2-methyl-3-oxahexyl, 1 -methoxypropyl-2-oxy, 1- ethoxypropyl-2-oxy, 1 -propoxypropyl-2-oxy, 1-butoxypropyl-2-oxy, 2- fluorooctyloxy, 2-fluorodecyloxy, 1,1 ,1 -trif luoro-2-octyloxy, 1,1,1 -trif luoro-2- octyl, 2-fluoromethyloctyloxy for example. Very preferred are 2-hexyl, 2- octyl, 2-octyloxy, 1 ,1 ,1-trifluoro-2-hexyl, 1 ,1 , 1 -trif luoro-2-octyl and 1 ,1,1- trifluoro-2-octyloxy.

In addition, compounds containing an achiral branched alkyl group may occasionally be of importance, for example, due to a reduction in the tendency towards crystallization. Branched groups of this type generally do not contain more than one chain branch. Preferred achiral branched groups are isopropyl, isobutyl (= methylpropyl), isopentyl (= 3-methylbutyl), isopropoxy, 2-methyl-propoxy and 3-methylbutoxy. from

CH₂=CW²-(0)_k1-, CH₃-CH=CH-0-, (CH₂=CH)₂CH-OCO-,

(CH₂=CH-CH₂)₂CH-OCO-, (CH₂=CH)₂CH-0-, (CH₂=CH-CH₂)₂N-, HO-CW²W³-, HS-CW²W³-, HW²N-, HO-CW²W³-NH-, CH₂=CW¹-CO-NH-, CH₂=CH-(COO)_k1-Phe-(0)_k2-, Phe-CH=CH-, HOOC-, OCN-, and W⁴W⁵W⁶Si-, with W¹ being H, CI, CN, phenyl or alkyl with 1 to o 5 C-atoms, in particular H, CI or CH₃, W² and W³ being independently of each other H or alkyl with 1 to 5 C-atoms, in particular methyl, ethyl or n- propyl, W⁴, W⁵ and W⁶ being independently of each other CI, oxaalkyl or oxacarbonylalkyl with 1 to 5 C-atoms, Phe being 1 ,4-phenylene and ki and k₂ being independently of each other 0 or 1. 5

Especially preferably PG is a vinyl group, an acrylate group, a methacrylate group, an oxetane group or an epoxy group, especially preferably an acrylate or methacrylate group. o As for the spacer group SG all groups can be used that are known for this purpose to those skilled in the art. The spacer group SG is preferably of formula SG'-X, such that PG-SG- is PG-SG'-X-, wherein

SG' is alkylene with up to 20 C atoms which may be unsubstituted, mono-5 or poly-substituted by F, CI, Br, I or CN, it being also possible for one or more non-adjacent CH₂ groups to be replaced, in each case independently from one another, by -0-, -S-, -NH-, -NR⁰¹-, -SiR⁰¹ R⁰²-, -CO-, -COO-, -OCO-, -OCO-0-, -S-, -CO-, -CO-S-, -CH=CH- or -C≡C- in such a manner that O and/or S atoms are not linked directly to one0 another,

X is -0-, -S-, -CO-, -COO-, -OCO-, -0-COO-, -CO-NR⁰¹-, -NR⁰¹-CO-, - OCH₂-, -CH2O-, -SCH₂-, -CH₂S-, -CF₂0-, -OCF₂-, -CF₂S-, -SCF₂-, -CF₂CH₂-, -CH₂CF₂-, -CF₂CF₂-, -CH=N-, -N=CH-, -N=N-, -CH=CR⁰¹-,₅ -CY⁰¹=CY⁰²-, -C≡C-, -CH=CH-COO-, -OCO-, -CH=CH- or a single bond, and R⁰¹, R⁰², Y and Y have one of the respective meanings given above.

X is preferably -0-, -S-, -OCH₂-, -CH₂0-, -SCH₂-, -CH₂S-, -CF₂0-, -OCF₂-, -CF S-, -SCF₂-_ι -CH₂CH₂-, -CF₂CH₂-, -CH CF₂-, -CF₂CF₂-, -CH=N-, -N=CH-, -N=N-, -CH=CR⁰-, -CY⁰²=CY⁰²-, -C≡C- or a single bond, in particular -0-, -S-, -C≡C-, -CY⁰¹=CY⁰²- or a single bond, very preferably a group that is able to from a conjugated system, such as -C≡C- or -CY⁰¹=CY⁰²-, or a single bond.

Typical groups SG¹ are, for example, -(CH₂)_P-, -(CH₂CH₂0)_q -CH₂CH₂-, -CH₂CH₂-S-CH₂CH2- or -CH2CH2-NH-CH2CH2- or -(SiR°R⁰⁰-O)_p-, with p being an integer from 2 to 12, q being an integer from 1 to 3 and R°, R⁰⁰ and the other parameters having the meanings given above.

Preferred groups SG¹ are ethylene, propylene, butylene, pentylene, hexylene, heptylene, octylene, nonyiene, decylene, undecylene, dodecylene, octadecylene, ethyleneoxyethylene, methyleneoxybutylene, ethylene-thioethylene, ethylene-N-methyl-iminoethylene, 1 -methylalkylene, ethenylene, propenylene and butenylene for example.

In another preferred embodiment SG' is a chiral group of formula I*':

-Q -CH-Q"

Of

wherein

Q¹ and Q³ have the meanings given in formula I^*, and

Q⁴ is an alkylene or alkylene-oxy group with 1 to 10 C atoms or a single bond, being different from Q¹,

with Q¹ being linked to the polymerisable group PG. Further preferred are compounds with one or two groups PG-SG- wherein SG is a single bond.

In case of compounds with two groups PG-SG, each of the two polymerisable groups PG and the two spacer groups SG can be identical or different.

Preferably the liquid crystalline media according to the instant invention contain a compound A comprising, preferably predominantly consisting of and most preferably entirely consisting of compounds of formula I.

The compounds of formula I preferably are prepared according to the following schemes.

The compounds of formula I with non-fused bulky end groups preferably are prepared according to the exemplary reactions shown in the following seven reaction schemes or in analogy to them (schemes I to VIII) in which the parameters have the respective meanings given above and phenyl rings may optionally be substituted by alkyl, alkoxy or halogen, preferably by halogen, most preferably by F. Reaction scheme VII is a scheme for the preparation of a chiral compound of formula I with a chiral end group R¹¹, whereas scheme VIII shows the preparation of a compound of formula I, wherein the central atom Z° is a N-atom.

Scheme

Scheme

Scheme

Scheme IV

Scheme V

Grignard

Scheme VI

Scheme VII

Scheme VIII

The compounds of formula I with fused bulky end groups preferably are prepared e.g. according to the following five schemes or in analogy to them (schemes IX to Xlll), in which the parameters have the respective meanings given above and in case they appear several times they have these meanings independently of each other and phenyl rings may optionally be substituted by alkyl, alkoxy or halogen, preferably by halogen, most preferably by F. Reaction scheme XI shows the preparation of a compound of formula I, wherein the central atom Z° is a N-atom.

Scheme IX

Scheme X

Scheme XI

Scheme XII

Scheme XIII

Comprising in this application means in the context of compositions that the entity referred to, e.g. the medium or the component, contains the compound or compounds in question, preferably in a total concentration of 10 % or more and most preferably of 20 % or more.

Predominantly consisting, in this context, means that the entity referred to contains 80 % or more, preferably 90 % or more and most preferably 95 % or more of the compound or compounds in question.

Entirely consisting, in this context, means that the entity referred to contains 98 % or more, preferably 99 % or more and most preferably 100.0 % of the compound or compounds in question.

The concentration of the compounds according to the present application are contained in the media according to the present application preferably is in the range from 0.5% or more to 30% or less, more preferably in the range from 1% or more to 20% or less and most preferably in the range from 5% or more to 12% or less.

The compounds of formula I with non-fused bulky end groups are preferably selected from the group of sub-formulae 1-1 to 1-15

35

wherein the parameters have the respective meanings given under formula I above and preferably

R 11 is alkyl, alkoxy, alkenyl or alkynyl, preferably alkyl or alkoxy,

R >13 and R ,14 are, independently of each other, H, F, CI or CN, preferably

R_A and R_A are, independently of each other, alkyl, alkenyl or alkynyl, preferably alkyl,

R_B 11 and 12 R_B are, independently of each other, H or CF₃,

Y and Y^■12 are, independently of each other, H, F or CN, preferably H, or F, preferably H, and

L 11 * t.o-. i L 14 are, independently of each other, H or F,

and chiral compounds of these compounds are encompassed too, in particular chiral compounds of formula 1-11. The compounds of formulae 1-1 to 1-11 preferably are selected from the following group of compounds of sub-formulae 1-1 a to 1-11, l-2a to l-2j, l-3a to l-3j, l-4a to l-4j, l-5a to l-5t, l-6a to l-6t, l-7a to l-7t, l-8a to l-8j, l-9a to l-9t, 1-10a to 1-1 Oj and 1-11a to 1-11j

35

30

35

35

35

35

35

35

35

35

35

35

35

35

35

35

35

35

35

wherein the parameters have the respective meanings given above and preferably

R is alkyl

R 11 is alkyl, alkenyl, alkynyl or alkoxy.

The compounds of formula M 1 a preferably are selected from the following group of compounds of sub-formulae 1-11aR and 1-11aS and their homologs

Other preferred compounds with a chiral bulky end group are those of formula 1-61 R, respectively 1-16S, and their homologs and of formulae 1-17R, respectively I-17S

wherein the parameters have the respective meanings given above and preferably R is alkyl or alkoxy.

The compounds of formula 1-12 preferably are selected from the following group of compounds of sub-formulae 1-12a and 1-12b

wherein the parameters have the respective meanings given above and preferably R¹¹ is alkyl or alkoxy.

Further preferred compounds of formula I are those of formulae 1-18 and 1-19

wherein the parameters have the respective meanings given above and preferably R¹¹ is alkyl or alkoxy.

In another preferred embodiment of the instant invention the compounds of formula I with non-fused bulky end groups are preferably selected from the group of sub-formulae I-20 to I-26

wherein the parameters have the respective meanings given above and preferably

R 11 is alkyl, alkoxy, NR, NR ₂, F, CN,

R -,1¹3³ and . r R-,1¹4⁴, independently of each other, are F, CN, H, methoxy, ethoxy or methyl

L¹¹ to L¹⁴ are, independently of each other, H or F, preferably one or two of them are F, the others H, R' are, independently of each other, alkyl, preferably methyl or ethyl

R' is alkyl or alkoxy, preferably methyl or methoxy.

In another preferred embodiment of the instant invention the compounds of formula I with non-fused bulky end groups are preferably selected from the group of sub-formulae 1-27 to 1-30

wherein the parameters have the respective meanings given above and preferably

R 11 is alkoxy, alkyl, NHR" or NR"₂, wherein R" has the meaning given above for R' and preferably is alkyl

R >13 _Λ a-nd R ι14 , independently of each other, are methyl, ethyl, methoxy, CN, F or CF3,

L¹¹ to L¹⁴ are, independently of each other, H or F, preferably one or two of them are F and the others H and

R' are, independently of each other, H, alkyl or alkoxy, preferably alkoxyl. preferably methyl, methoxy , or oxaalkyl ,

In another preferred embodiment of the instant invention the compounds of formula I with non-fused bulky end groups are preferably selected from the group of sub-formulae 1-31 to I-54

35

wherein the parameters have the respective meanings given above and preferably

R 11 is alkyl, preferably with 1 to 12 C-atoms, alkoxy, preferably with 1 to 11 C-atoms, F, CN or CF₃,

R¹³ and R¹⁴, independently of each other, are H, F or alkyl, preferably methyl, ethyl or H, preferably H,

R' is alkyl or alkoxy,

R"' is alkyl, preferably CH₃,

R^x is H or methyl and

L¹¹ to L 16 are, independently of each other, H or F, preferably all of them are H or one or two of them are F and the others H.

Examples of compounds of formula I with one non-fused bulky end group each according to the present invention are

35

35

35

30

35

35

35

In these formulae, like in the whole application, the C-atoms are saturated to their valence of four bonds with H-atoms, unless explicitly stated otherwise. I.e. centre atoms Z° according to formula I, which are shown with three substituents only bear a non-shown H-atom as the fourth substituent and all parameters, e.g. R are, respectively is, as defined above. Examples of compounds of formula I with one non-fused bulky end group each and m being

according to the present invention are

Examples of compounds of formula I with one non-fused bulky end group on each and

Jm being

according to the present invention are

Examples of compounds of formula I with one non-fused bulky end group each and m being

according to the present invention are

Examples of compounds of formula I with one non-fused bulky end group each and

m being

according to the present invention are

Examples of compounds of formula I with one non-fused bulky end group each and

Jm being

according to the present invention are

In a preferred embodiment of the instant invention the compounds of formula I have two bulky end groups. The compounds of formula I with two non-fused bulky end groups are preferably selected from the group of sub- formulae -1 to -4

wherein the parameters have the respective meanings given above and preferably

R ,13 and J r R-,14 , independently of each other, are alkoxy, alkyl or NR₂, wherein R is an alkyl group with alkyl preferably 1 C atoms up to 6 C atoms and

L¹¹ to L¹⁴, independently of each other, are H or F, methyl or methoxy.

Examples of compounds of formula I with two such bulky end groups according to the present invention are

The compounds of formula I with fused bulky end groups are preferably selected from the group of sub-formulae l^#-1 to l -28

35

35

15

35

wherein the parameters have the respective meanings given above and preferably 11 is alkoxy, alkyl (which both may be branched and also may be chiral, -C0₂-alkyl, -CF₃, -OCF₃ or F,

R' independently of each other, are H or F,

L¹¹ to L¹⁶, independently of each other, are H, F, methyl or methoxy and

Y¹¹ to Y¹⁴, independently of each other, are H, F, methyl or methoxy.

Examples of compounds of formula I with fused bulky end groups according to the present invention are

35

Furthermore, compounds with one fused and one non-fused bulky end group, as well as compounds with two fused bulky end groups, are preferred according to the present invention. These are preferably selected from the group of compounds of formulae I ## - H1 and ,j , I## -2

wherein the phenyl rings optionally may be further substituted, preferably by alkyl, alkoxy or halogen, preferably by halogen most preferably by F.

Examples of compounds of formula I with one fused and one non-fused bulky end group according to the present invention are

Examples of compounds of formula I with two fused bulky end groups according to the present invention are

In a preferred embodiment the mesogenic modulation media according to the instant invention comprise

- a component A, preferably in a concentration of 1 % to 25 % by weight, comprising, preferably predominantly consisting of and most preferably entirely consisting of, one compound or more compounds of the formula I given above and

- optionally a dielectrically positive component B comprising, preferably predominantly consisting of and most preferably entirely consisting of one compound or of more compounds of formula II

wherein

R² has the meaning given under formula I for R¹¹,

A²¹, A²² and A²³ are, each independently of each other,

whereby each of A²¹ and A²² may have the same or a different meaning if present twice,

Z²¹ and Z²² are, each independently of each other, a single bond,

-(CH₂)₄)-, -CH₂CH₂-, -CF2-CF2-, -CF₂-CH₂-, -CH₂-CF₂-, -CH=CH-, -CF=CF-, -CF=CH-, -(CH₂)₃0-, -0(CH₂)₃-, -CH=CF-, -C≡C-, -CH₂O-, -OCH₂-, -CF₂0-, -OCF₂-, -CO-O- or -O-CO-, whereby each of Z²¹ and Z²² may have the same or a different meaning if present twice,

X² is halogen, -CN, -NCS, -SF₅, -SO2CF₃, alkyl, alkenyl, alkenyloxy or alkylalkoxy or alkoxy radical each mono- or polysubstituted by CN and/or halogen,

L²¹ and L²² are, each independently of each other, H or F, and

m is O, 1 or 2,

is O, 1 , 2 or 3,

o is 0, 1 or 2, preferably 0 or 1 and

m + n + o is 3 or less, preferably 2 or less,

- optionally a component C, preferably in a concentration of 1 % to 25 % by weight, comprising, preferably predominantly consisting of and most preferably entirely consisting of one compound or of more compounds of formula III

wherein

a, b, c and d are each independently of each other 0, 1 or 2, whereby

a + b + c + d is 4 or less,

^31 ^32 ^33

and A³⁴ are, each independently of each other,

whereby each of A³¹ , A³², A³³ and A³⁴ may have the same or a different meaning if present twice,

z³¹, z³², z³³ and Z³⁴ are, each independently of each other, a single bond,

-(CH2)4)"j -CH2CH2-, -CF2-CF2-, -CF2-CH2-, "CH2-CF2-,

-CH=CH-, -CF=CF-, -CF=CH-, -(CH₂)₃0-, -0(CH₂)₃-, -CH=CF-, -C≡D-, -CH₂O-, -OCH₂-, -CF₂O-, -OCF2-,

-CO-O- or -O-CO-, whereby each of Z³ , Z³², Z³³ and Z³⁴ may have the same or a different meaning if present twice,

R³ is an alkyl or alkoxy radical having from 1 to 15 carbon atoms, wherein one or more methylene groups of said alkyl or alkoxy radical may be replaced independently of each other by -0-, -S-, -SiR^xR^y-, -CH=CH-, -C≡D-, -CO-O- and/or -O-CO- such that oxygen and/or sulfur atoms are not linked directly to each other, said alkyl or alkoxy radical being unsubstituted or mono-substituted with a -CN group or mono- or poly-substituted with halogen, preferably R¹¹ is a straight-chain alkyl, alkoxy, alkenyl, alkenyloxy or -0-alkylene-O-alkyl radical with up to 10 carbon atoms, said radicals being unsubstituted or mono- or poly-substituted with halogen,

L³¹, L³², L³³ and L³⁴ are each independently of each other hydrogen, halogen, a CN group, an alkyl or alkoxy radical having from 1 to 15 carbon atoms wherein one or more methylene groups of said alkyl or alkoxy radical may be replaced independently of each other by -0-, -S-, -SiR^xR^y-, -CH=CH-, -OD-. -CO-O- and/or -O-CO- such that oxygen and/or sulfur atoms are not linked directly to each other, said alkyl or alkoxy radical being unsubstituted or mono-substituted with a -CN group or mono- or poly-substituted with halogen, with the proviso that at least one of L³ , L³², L³³ and L³⁴ is not hydrogen,

XZ^ύ is F, CI, CF₃, OCF₃, CN, NCS, -SF₅ or -S0₂-R^z,

R^x and R^y are independently of each other hydrogen or an alkyl radical having from 1 to 7 carbon atoms; preferably R^x and R^y are both methyl, ethyl, propyl or butyl, and

R^z is an alkyl radical having from 1 to 7 carbon atoms, said alkyl radical being unsubstituted or mono- or polysubstituted with halogen; preferably R² is CF₃, C₂F₅ or

- 1 -20 % by weight of component D comprising one chiral compound or more chiral compounds with a HTP of ≥ 20 μm.

The inventive mixtures contain 1-25 wt.%, preferably 2-20 wt.% and most preferably 3-15 wt.% of component A.

Preferred compounds of formula II are compounds selected of the group of formulae 11-1 to II-8:

35

wherein the parameters have the respective meanings given under formula II and preferably

R is straight chain alkyl or alkoxy with up to six carbon atoms and

X is F, CN, NCS, CF₃, SF₅ or OCF₃.

Especially preferred are compounds of the formulae ll-5 and II-8.

The inventive mixtures contain 20-80 wt.% of the pyrane compounds of the formulae II, preferably 25-70 wt.% and especially preferred 30-60 wt.%.

In a preferred embodiment of the present invention the compounds of formula III are selected from the group of compounds of the formulae 111-1 to III-7

wherein the parameters have the respective meanings given under formula III and preferably

is O or 1 ,

d is 0, 1 or 2, preferably 0 or 1 , especially preferred 1 ;

R^J is an alkyl or alkoxy radical having from 1 to 15 carbon atoms or an alkenyl or alkenyloxy or -O-alkylene-0-alkyl radical having from 2 to 15 carbon atoms, wherein one or more methylene groups of each of said radicals may be replaced independently of each other by -S-, -SiR^xR^y-, -C≡D-, -CO-O- and/or -O-CO- such that oxygen and/or sulfur and/or Si atoms are not linked directly to each other, said radicals being unsubstituted or mono-substituted with a -CN group or mono- or polysubstituted with halogen, preferably R³ is a straight- chain alkyl, alkoxy, alkenyl, alkenyloxy or -O-alkylene-O- alkyl radical with up to 10 carbon atoms, said radicals o being unsubstituted or mono- or poly-substituted with halogen,

L³¹ , independently, has one of the meanings given for R³ and preferably is a straight-chain alkyl, alkoxy, alkenyl,5 alkenyloxy or -O-alkylene-O-alkyl radical with up to 10 carbon atoms, said radicals being unsubstituted or mono- or poly-substituted with halogen,

L³² , independently, has one of the meanings given for R³0 or alternatively is hydrogen, halogen and preferably is

H, F, a straight-chain alkyl, alkoxy, alkenyl, alkenyloxy or -O-alkylene-O-alkyl radical with up to 10 carbon atoms, said radicals being unsubstituted or mono- or polysubstituted with halogen, 5 j 35 ■ 36 L³⁷, L³⁸

.39 ■ 39a .39b *- > and L^39c are, independently of each other, H or F and in formulae 111-1 to III-4 preferably at least L³⁵ is F and in formulae0 III-3 and Hl-4 preferably additionally L³⁸ is F, whereas in formula III-7 preferably additionally L³⁶ is F and in formulae III-5 and III-6 preferably at least both L³⁷ and L^39b are F, 5 X³ is F, CI, -CN, -NCS, -SF₅, -S0₂-R^z, an alkyl or alkoxy radical having from 1 to 15 carbon atoms, wherein one or more methylene groups of said alkyl or alkoxy radical may be replaced independently of each other by -0-, -S-, -SiR^xR^y-, -CH=CH-, -C≡C-, -CO-O- and/or -O-CO- such that oxygen and/or sulfur atoms are not linked directly to each other, said alkyl or alkoxy radical being unsubstituted or mono-substituted with a -CN group or mono- or poly-substituted with halogen; preferably X³ is F, CI, CF₃, OCF₃, OCHF₂, NCS, SF₅ or -S0₂-R^z,

Y³ is an alkyl or alkoxy radical having from 1 to 15 carbon atoms or an alkenyl or alkenyloxy or -O-alkylene-O-alkyl radical having from 2 to 15 carbon atoms, wherein one or more methylene groups of each of said radicals may be replaced independently of each other by -S-, -SiR^xR^y-, -C≡C-, -CO-O- and/or -O-CO- such that oxygen and/or sulfur atoms are not linked directly to each other, said radicals being unsubstituted or mono- substituted with a -CN group or mono- or polysubstituted with halogen, preferably Y³¹ is an alkoxy, alkenyloxy or -O-alkylene-O-alkyl radical with up to 10 carbon atoms, said radicals being unsubstituted or mono- or poly-substituted with halogen; in particular Y³¹ has the same meaning as L³¹,

Y³² is hydrogen, halogen, an alkyl or alkoxy radical having from 1 to 15 carbon atoms or an alkenyl or alkenyloxy or -O-alkylene-O-alkyl radical having from 2 to 15 carbon atoms, wherein one or more methylene groups of each of said radicals may be replaced independently of each other by -S-, -SiR^xR^y-, -C≡C-, -CO-O- and/or -O-CO- such that oxygen and/or sulfur atoms are not linked directly to each other, said radicals being unsubstituted or mono-substituted with a -CN group or mono- or polysubstituted with halogen, preferably Y³² is H, Z³³ and Z³⁴ are, independently of each other, a single bond,

-CH₂CH₂-, (-CH₂CH₂-) , -CF2-CF₂-, -CF₂-CH2-, -CH₂-CF₂-, -CH=CH-, -CF=CF-, -CF=CH-, -CH=CF-, -C≡D-, -CH2O-, -OCH₂-, -CF₂0-, -OCF2-, -CO-O- or -O-CO-, preferably Z³⁴ is a single bond, -C≡C-, -CF₂0- or -CO2-, in particular a single bond or -CF₂0-, and in formulae 111-3 and 111-4 preferably one or both of Z³³ and Z³⁴ is a single bond, more preferably Z³³ and Z³⁴ are both a single bond or one of Z³³ and Z³⁴ alternatively is -CF₂0- or -C0₂-,

R^x and R^y are independently of each other hydrogen or an alkyl radical having from 1 to 7 carbon atoms; preferably both R and R^y are methyl, ethyl, propyl or butyl;

R^z is an alkyl radical having from 1 to 7 carbon atoms, said alkyl radical being unsubstituted or mono- or polysubstituted with halogen; preferably R^z is CF₃, C₂F₅ or n-C₄F₉,

whereby it is further preferred that at least one of R³, L³¹ and L³² is one of said straight-chain alkyl, alkoxy, alkenyl, alkenyloxy or -O-alkylene-O-alkyl radicals.

Suitable chiral compounds of component D are those which have an absolute value of the helical twisting power of 20 μm or more, preferably of 40 μ or more and most preferably of 60 μm or more. The HTP is measured in MLD-6260 at a temperature of 20°C.

The chiral component D comprises preferably one or more chiral compounds which have a mesogenic structure und exhibit preferably one or more mesophases themselves, particularly at least one cholesteric phase. Preferred chiral compounds being comprised in the chiral component D are, inter alia, well known chiral dopants like cholesteryl- nonanoate (CN), R/S-811 , R/S-1011 , R/S-2011 , R/S-3011 , R/S-4011 ,

R/S-5011 , CB-15 (Merck KGaA, Darmstadt, Germany). Preferred are chiral dopants having one or more chiral moieties and one or more mesogenic groups or having one or more aromatic or alicyclic moieties forming, together with the chiral moiety, a mesogenic group. More preferred are chiral moieties and mesogenic chiral compounds disclosed in DE 34 25 503, DE 35 34 777, DE 35 34 778, DE 35 34 779, DE 35 34 780, DE 43 42 280, EP 01 038 941 and DE 195 41 820 that disclosure is incorporated within this application by way of reference. Particular preference is given to chiral binaphthyl derivatives as disclosed in EP 01 111 954.2, chiral binaphthol derivatives as disclosed in WO 02/34739, chiral TADDOL derivatives as disclosed in WO 02/06265 as well as chiral dopants having at least one fluorinated linker and one end chiral moiety or one central chiral moiety as disclosed in WO 02/06196 and WO 02/06195.

The controlling medium of the present invention has a characteristic temperature, preferably a clearing point, in the range from about -30 °C to about 80 °C, especially up to about 55 °C.

Preferred chiral compounds of the component D are selected from the group of the compounds D-l to D-lll.

wherein

p_>a11 _Ra12 are each independently from each other alkyl, oxalkyl, pa21 p^a22 alkoxy or alkenyl with up 9 carbon atoms with the

R^a31'and R^a32 provisos that

_Ra11 _{+ R}a12 a) Ra21 _{+ R}a22 b)

Preferably R ,a^d1"1, R ₀a^a1^>2, R ₀a21 , R r-,a22 , R r-,a^a3^j1^l and R a^a3^2 are an alkyl group, especially a straight chain alkyl group.

Especially preferred are chiral binaphthyl derivates of the formulae D-IV,

Especially preferred are binaphthyl derivatives of the formulae D-IV-1a to D-IV-l c,

wherein

Z° is single bond, -CH₂CH₂-, -COO-, -OCO-, -CF₂0-, -OCF2-, -CH2O-, -OCH2-, -CF2- CF2-, -CH=CH-, -C≡D- or -CF=CF-,

R' 0* is hydrogen, an alkyl or alkoxy radical having from 1 to 15 carbon atoms wherein one or more methylene groups of said alkyl or alkoxy radical may be replaced independently of each other by -0-. -S-, -SiR^xR^Y-, -CH=CH-, -C≡D-, -CO-O- and/or -O-Cl- such that oxygen and/or sulfur atoms are not linked directly to each other, said alkyl or alkoxy radical being unsubstituted or mono- or poly-substituted with halogen,

Furthermore chiral binaphthyl derivates of the formulae D-V and D-VI are preferred

wherein Z and b have the above given meanings and X is

H, F, CI, CN or has the meaning of R°\ R^2* and R are each independently is F, CI, OCFs, CF₃, CN and L¹, L², L³ and L⁴ are each H or F. Z°^* denotes single bond, -C₂H₄-, -COO-, -OCO-, CH₂0-, -OCH₂-, -C₂F₄, -CH=CH-, -C≡D- or -CF=CF

Especially preferred are chiral binaphthyl derivatives of the formulae D- V-2a to D-V-2f :

The inventive mixtures contain one ore more (two, three, four or more) chiral compounds in the range of 1-25 wt.%, preferably 2-20 wt.%. Especially preferred are mixtures containing 3-15 wt.% of a chiral compound.

Preferred embodiments are indicated below:

The medium comprises one, two or more compounds of formula I;

Component B preferably contains besides one compound ore more compounds of formula II one ester compound or more ester compounds of the formula Z

wherein R^z has the meaning given under formula I for R¹¹,

y—

X^z is F, CI, CN, NCS, OCF₃, CF₃ or SF₅.

Preferred compounds of the formula Z are selected from the group of compounds of formulae Z-1 to Z-14

35

wherein R has the meaning given under formula Z for R^z. Especially preferred are mixtures containing 5 % to 35 %, preferably 10 % to 30 % and especially preferred 10 % to 20 % of compounds of formula Z, preferably selected from the group of formulae Z-1 to Z-14.

The component B preferably contains additionally one or more compounds selected from the group of ester compounds of formulae N-1 to N-10

Alkyl-C≡C- O -COO — { O )—C N-1

wherein

R has the meaning given under formula I for R 11 and

"Alkyl" is alkyl with 1 to 7 C-atoms, preferably n-alkyl.

The medium component B additionally comprises one or more compounds selected from the group consisting of the general formulae IV to VIII

wherein

R^L is n-alkyl, alkoxy, oxaalkyl, fluoroalkyl or alkenyl, each having up to 9 carbon atoms,

X^u is CN, SF₄, NCS, S0₂CF₃, F, CI, halogenated alkyl, halogenated alkenyl, halogenated alkenyloxy or halogenated alkoxy having up to 6 carbon atoms,

is -C2F4-, -CF=CF-, -C2H4-, -(CH₂)₄-, -OCH2-, -CH≥O-, -CH=CH-, -CF2O- or -OCF2-, -C₂F₄-,

Y¹ to Y⁴ are each, independently of one another, H or F and r is 0 or 1 and

wherein further compounds of formula VII are excluded from formula VIII.

The compounds of the formula VI are preferably selected from the group of compounds of formulae VI-1 to VI-5, preferably of VI-1 and/or VI-2 and /or VI-4, most preferably of VI-2 and/or VI-4,

wherein the parameters have the respective meanings given under formula VI above. The component B preferably additionally comprises one compound or more compounds with four six-membered rings selected from the group consisting of the general formulae IX to XVI:

in which R°, X° and Y¹ to Y⁴ have the respective meanings given under formulae IV to VIII and preferably

X° is F, CI, CF₃, OCF₃ or OCHF₂ ,

R° is alkyl, oxaalkyl, fluoroalkyl or alkenyl, each having up to 6 carbon atoms.

The component B preferably additionally comprises one or more compounds selected from the group of ester compounds of formulae E-1 to E-4

in which R° is as defined under formulae IV to Vlll.

The proportion of the compounds of the formulae E-1 to E-4 is preferably 10-30% by weight, in particular 15 % to 25 %.

The proportion of compounds of the formulae III to Vlll in the mixture as a whole is preferably from 1 % to 30 %.

O OCF_Q, OCF₃, — 2>- CF₃,

F

O VOCHF,, — (O V-CI, — (θ )-CI or — oVci.

^ Q - The medium comprises compounds of the formulae II, III, IV, V, VI and/or VII.

R° preferably is straight-chain alkyl or alkenyl having from 2 to 7 carbon atoms.

15

Component B preferably comprises further compounds, preferably selected from the following group consisting of the general formulae XVII to XXI:

25 R^u XVIII

30

5

wherein R° and X° are as defined under formulae IV to VII and the 1 ,4-phenylene rings optionally may additionally be substituted by CN, CI or Fluorine, preferably by F. The 1 ,4-phenylene rings are preferably monosubstituted or polysubstituted by F atoms.

The medium preferably additionally comprises one compound, two, three or more, preferably two or three, compounds selected from the group of compounds of the formulae 0-1 and 0-2

wherein "Alkyl" and "Alkyl ' ", independently of each other, are as defined under formulae N-1 to N-6.

The proportion of the compounds of the formulae 0-1 and/or 0-2 in the mixtures according to the invention is preferably 5 % to 10 % by weight.

The medium preferably comprises one compound, two or three compounds of formula VII-4 in which X° is F or OCF₃.

The medium preferably comprises one compound or more compounds of the formulae IV- 1 to IV-7

wherein R has the meaning given under formula IV and preferably is methyl, ethyl, n-propyl, n-butyl, n-pentyl or vinyl.

The medium preferably comprises one compound or more compounds selected from the group of formulae Q-1 to Q-9

wherein R iO has the meaning given under formulae IV to Vlll.

The proportion of the compounds of the formula VI-1 and/or Vl-12, in which X° preferably is fluorine, and R° preferably is CH₃, C₂H₅, n-C₃H₇, n-C4H₉, n-CsHn or vinyl, in the mixture as a whole is from 2 % to 20 %, in particular from 2 % to 15 %.

The medium preferably comprises one compound or more compounds selected from the group of compounds of formulae ll to VII in which R° is methyl.

The medium particularly preferably comprises one compound or more compounds selected from the group of compounds of formulae IV-1a, IV-2a and Q-7a

The medium preferably comprises one dioxane compound, two or more dioxane compounds, preferably one dioxane compound or two dioxane compounds, selected from the group of formulae Dx-1 and

Dx-2

The medium preferably additionally comprises one, two or more compounds with two cyclohexane rings selected from the group of formulae Z-1 to Z-6

wherein R° has the meaning given under formulae IV to Vlll, "Alkyl" and "Alkyl ' " have the respective meanings given under formulae 0-1 and 0-2 and

R^1a and R^2a are, each independently of each other, H, CH₃,

C₂H₅ or n-C₃H_7ι

The medium preferably comprises one, two or more compounds with two cyclohexane rings selected from the group of formulae Z-1 , Z-2, Z-5 and Z-6. The medium preferably additionally comprises one, two or more compounds having fused rings, of the formulae AN-1 to AN-11

wherein R° has the meaning given under formulae IV to Vlll.

It has been found that even a relatively small proportion of compounds of the formulae I mixed with conventional liquid-crystal materials, but in particular with one or more compounds of the formulae II, III, IV, V, VI VII and/or Vlll, results in a lower operating voltage and a broader operating temperature range. Preference is given, in particular, to mixtures which, besides one or more compounds of the formulae I, comprise one or more compounds of the formula II, in particular compounds of the formula ll-5 and II-7 in which X² is F, CI, CN, NCS, CF₃ or OCF₃. The compounds of the formulae I to Vlll are colourless, stable and readily miscible with one another and with other liquid-crystalline materials.

The optimum mixing ratio of the compounds of the formulae I and II + III + IV + V + VI + VII + Vlll depends substantially on the desired properties, on the choice of the components of the formulae I, II, III, IV, V, VI, VII and/or Vlll, and on the choice of any other components that may be present. Suitable mixing ratios within the range given above can easily be determined from case to case.

The total amount of compounds of the formulae I to XXI in the mixtures according to the invention is not crucial. The mixtures can therefore comprise one or more further components for the purposes of optimisation of various properties. However, the observed effect on the operating voltage and the operating temperature range is generally greater, the higher the total concentration of compounds of the formulae I to XXI.

In a particularly preferred embodiment, the media according to the invention comprise compounds of the formulae HI to Vlll in which X° is F, OCF₃, OCHF₂, OCH=CF₂, OCF=CF₂ or OCF₂-CF₂H. A favourable synergistic effect with the compounds of the formulae I results in particularly advantageous properties. In particular, mixtures comprising compounds of formula I and of formula II and of formula 111 are distinguished by their low operating voltages.

The individual compounds of the formulae II to XXI and their respective sub-formulae which can be used in the media according to the invention are either known or can be prepared analogously to the known compounds.

The construction of the MLC display according to the invention from polarisers, electrode base plates and surface-treated electrodes corresponds to the conventional construction for displays of this type. The term conventional construction is broadly drawn here and also covers all derivatives and modifications of the MLC display, in particular including matrix display elements based on poly-Si TFT or MIM, however, particularly preferred are displays, which have electrodes on just one of the substrates, i.e. so called interdigital electrodes, as those used in IPS displays, preferably in one of the established structures.

A significant difference between the displays according to the invention and the conventional displays based on the twisted nematic cell consists, however, in the choice of the liquid-crystal parameters of the liquid-crystal layer.

The media according to the invention are prepared in a manner conventional per se. In general, the components are dissolved in one another, advantageously at elevated temperature. By means of suitable additives, the liquid-crystalline phases in accordance with the invention can be modified in such a way that they can be used in all types of liquid crystal display elements that have been disclosed hitherto. Additives of this type are known to the person skilled in the art and are described in detail in the literature (H. Kelker and R. Hatz, Handbook of Liquid Crystals, Verlag Chemie, Weinheim, 1980). For example, pleochroic dyes can be added for the preparation of coloured guest-host systems or substances can be added in order to modify the dielectric anisotropy, the viscosity and/or the alignment of the nematic phases. Furthermore, stabilisers and antioxidants can be added.

The mixtures according to the invention are suitable for TN, STN, ECB and IPS applications and isotropic switching mode (ISM) applications. Hence, there use in an electro-optical device and an electro-optical device containing liquid crystal media comprising at least one compound according to the invention are subject matters of the present invention.

The inventive mixtures are highly suitable for devices which operate in an optically isotropic state. The mixtures of the invention are surprisingly found to be highly suitable for the respective use.

Electro-optical devices that are operated or operable in an optically isotropic state recently have become of interest with respect to video, TV, and multi-media applications. This is because conventional liquid crystal displays utilizing electro-optical effects based on the physical properties of liquid crystals exhibit a rather high switching time which is undesired for said applications. Furthermore most of the conventional displays show a significant viewing angle dependence of contrast that in turn makes necessary measures to compensate this undesired property.

With regard to devices utilizing electro-optical effects in an isotropic state the German Patent Application DE 102 17273 A1 for example discloses light controlling (light modulation) elements in which the mesogenic controlling medium for modulation is in the isotropic phase at the operating temperature. These light controlling elements have a very short switching time and a good viewing angle dependence of contrast. However, the driving or operating voltages of said elements are very often unsuitably high for some applications.

German Patent Application DE 10241 301 yet unpublished describes specific structures of electrodes allowing a significant reduction of the driving voltages. However, these electrodes make the process of manufacturing the light controlling elements more complicated.

Furthermore, the light controlling elements, for example, disclosed in both DE 102 17273 A1 and DE 10241 301 show a significant temperature dependence. The electro-optical effect that can be induced by the electrical field in the controlling medium being in an optical isotropic state is most pronounced at temperatures close to the clearing point of the controlling medium. In this range the light controlling elements have the lowest values of their characteristic voltages and, thus, require the lowest operating voltages. As temperature increases the characteristic voltages and hence the operating voltages increase remarkably. Typical values of the temperature dependence are in the range from about a few volts per centigrade up to about ten or more volts per centigrade. While DE 102 41 301 describes various structures of electrodes for devices operable or operated in the isotropic state, DE 102 17273 A1 discloses isotropic media of varying composition that are useful in light controlling elements operable or operated in the isotropic state. The relative temperature dependence of the threshold voltage in these light controlling elements is at a temperature of 1 centigrade above the clearing point in the range of about 50%/centigrade. That temperature dependence decreases with increasing temperature so that it is at a temperature of 5 centigrade above the clearing point of about 10%/centigrade. However, for many practical applications of displays utilizing said light controlling elements the temperature dependence of the electro-optical effect is too high. To the contrary, for practical uses it is desired that the operating voltages are independent from the operating temperature over a temperature range of at least some centigrades, preferably of about 5 centigrades or more, even more preferably of about 10 centigrades or more and especially of about 20 centigrades or more.

Now it has been found that the use of the inventive mixtures are highly suitable as controlling media in the light controlling elements as described above and in DE 102 17 273 A1 , DE 102 41 301 and DE 102 536 06 and broaden the temperature range in which the operating voltages of said electro-optical operates. In this case the optical isotropic state or the blue phase is almost completely or completely independent from the operating temperature.

This effect is even more distinct if the mesogenic controlling media exhibit at least one so-called "blue phase" as described in yet unpublished DE 103 13 979. Liquid crystals having an extremely high chiral twist may have one or more optically isotropic phases. If they have a respective cholesteric pitch, these phases might appear bluish in a cell having a sufficiently large cell gap. Those phases are therefore also called "blue phases" (Gray and Goodby, "Smectic Liquid Crystals, Textures and Structures", Leonhard Hill, USA, Canada (1984)). Effects of electrical fields on liquid crystals existing in a blue phase are described for instance in H.S. Kitzerow, "The Effect of Electric Fields on Blue Phases", Mol. Cryst. Liq.

Cryst. (1991), Vol. 202, p. 51-83, as well as the three types of blue phases identified so far, namely BP I, BP ll, and BP III, that may be observed in field-free liquid crystals. It is noteworthy, that if the liquid crystal exhibiting a blue phase or blue phases is subjected to an electrical field, further blue phases or other phases different from the blue phases I, II and III might appear. The inventive mixtures can be used in an electro-optical light controlling element which comprises

one or more, especially two substrates; - an assembly of electrodes; one or more elements for polarizing the light; and said controlling medium;

whereby said light controlling element is operated (or operable) at a temperature at which the controlling medium is in an optically isotropic phase when it is in a non-driven state.

The controlling medium of the present invention has a characteristic temperature, preferably a clearing point, in the range from about -30 °C to about 80 °C, especially up to about 55 °C. -

The operating temperature of the light controlling elements is preferably above the characteristic temperature of the controlling medium said temperature being usually the transition temperature of the controlling medium to the blue phase; generally the operating temperature is in the range of about 0.1 ° to about 50 °, preferably in the range of about 0.1 ° to about 10 ° above said characteristic temperature. It is highly preferred that the operating temperature is in the range from the transition temperature of the controlling medium to the blue phase up to the transition temperature of the controlling medium to the isotropic phase which is the clearing point. The light controlling elements, however, may also be operated at temperatures at which the controlling medium is in the isotropic phase.

(For the purposes of the present invention the term "characteristic temperature" is defined as follows:

If the characteristic voltage as a function of temperature has a minimum, the temperature at this minimum is denoted as characteristic temperature. If the characteristic voltage as a function of temperature has no minimum and if the controlling medium has one or more blue phases, the transition temperature to the blue phase is denoted as characteristic temperature; in case there are more than one blue phase, the lowest transition temperature to a blue phase is denoted as characteristic temperature.

If the characteristic voltage as a function of temperature has no minimum and if the controlling medium has no blue phase, the transition temperature to the isotropic phase is denoted as characteristic temperature.)

In the context of the present invention the term "alkyl" means, as long as it is not defined in a different manner elsewhere in this description or in the claims, straight-chain and branched hydrocarbon (aliphatic) radicals with 1 to 15 carbon atoms. The hydrocarbon radicals may be unsubstituted or substituted with one or more substituents being independently selected from the group consisting of F, CI, Br, I or CN.

The dielectrics may also comprise further additives known to the person skilled in the art and described in the literature. For example, 0 to 5% of pleochroic dyes, antioxidants or stabilizers can be added.

C denotes a crystalline phase, S a smectic phase, Sc a smectic C phase, N a nematic phase, I the isotropic phase and BP the blue phase.

V_x denotes the voltage for X% transmission. Thus e.g. V₁₀ denotes the voltage for 10% transmission and V₁₀₀ denotes the voltage for 100% transmission (viewing angle perpendicular to the plate surface). t_on (respectively τ_on) denotes the switch-on time and t_off (respectively τ_off) the switch-off time at an operating voltage corresponding the value of V₁₀₀, respectively of V_max.

Δn denotes the optical anisotropy. Δε denotes the dielectric anisotropy (Δε = ε_(| - ε^, where ε_l( denotes the dielectric constant parallel to the longitudinal molecular axes and ε_λ denotes the dielectric constant perpendicular thereto). The electro-optical data are measured in a TN cell at the 1^st minimum of transmission (i.e. at a (d • Δn) value of 0.5 μm) at 20°C, unless expressly stated otherwise. The optical data are measured at 20°C, unless expressly stated otherwise.

Optionally, the light modulation media according to the present invention can comprise further liquid crystal compounds in order to adjust the physical properties. Such compounds are known to the expert. Their concentration in the media according to the instant invention is preferably 0 % to 30 %, more preferably 0 % to 20 % and most preferably 5 % to15 %.

Preferably inventive media have a range of the blue phase or, in case of the occurrence of more than one blue phase, a combined range of the blue phases, with a width of 9° or more, preferably of 10° or more, more preferably of 15° or more and most preferably of 20° or more.

In a preferred embodiment this phase range at least from 10°C to 30°C, most preferably at least from 10°C to 40°C and most preferably at least from 0°C to 50°C, wherein at least means, that preferably the phase extends to temperatures below the lower limit and at the same time, that it extends to temperatures above the upper limit.

In another preferred embodiment this phase range at least from 20°C to 40°C, most preferably at least from 30°C to 80°C and most preferably at least from 30°C to 90°C. This embodiment is particularly suited for displays with a strong back light, dissipating energy and thus heating the display.

In the present application the term dielectrically positive compounds describes compounds with Δε > 1 ,5, dielectrically neutral compounds are compounds with -1 ,5 < Δε < 1 ,5 and dielectrically negative compounds are compounds with Δε < -1 ,5. The same holds for components. Δε is determined at 1 kHz and 20 °C. The dielectrical anisotropies of the compounds is determined from the results of a solution of 10 % of the individual compounds in a nematic host mixture. The capacities of these test mixtures are determined both in a cell with homeotropic and with homogeneous alignment. The cell gap of both types of cells is approximately 20 μm. The voltage applied is a rectangular wave with a frequency of 1 kHz and a root mean square value typically of 0.5 V to 1.0 V, however, it is always selected to be below the capacitive threshold of the respective test mixture.

For dielectrically positive compounds the mixture ZLI-4792 and for dielectrically neutral, as well as for dielectrically negative compounds, the mixture ZLI-3086, both of Merck KGaA, Germany are used as host mixture, respectively. The dielectric permittivities of the compounds are determined from the change of the respective values of the host mixture upon addition of the compounds of interest and are extrapolated to a concentration of the compounds of interest of 100 %.

Components having a nematic phase at the measurement temperature of 20 °C are measured as such, all others are treated like compounds.

The term threshold voltage refers in the instant application to the optical threshold and is given for 10 % relative contrast (V-io) and the term saturation voltage refers to the optical saturation and is given for 90 % relative contrast (V_go) both, if not explicitly stated otherwise. The capacitive threshold voltage (V₀, also called Freedericksz-threshold V_Fr) is only used if explicitly mentioned.

The ranges of parameters given in this application are all including the limiting values, unless explicitly stated otherwise.

Throughout this application, unless explicitly stated otherwise, all concentrations are given in mass percent and relate to the respective complete mixture, all temperatures are given in degrees centigrade

(Celsius) and all differences of temperatures in degrees centigrade. All physical properties have been and are determined according to "Merck Liquid Crystals, Physical Properties of Liquid Crystals", Status Nov. 1997, Merck KGaA, Germany and are given for a temperature of 20 °C, unless explicitly stated otherwise. The optical anisotropy (Δn) is determined at a wavelength of 589.3 nm. The dielectric anisotropy (Δε) is determined at a frequency of 1 kHz. The threshold voltages, as well as all other electro- optical properties have been determined with test cells prepared at Merck KGaA, Germany. The test cells for the determination of Δε had a cell gap of 22 μ . The electrode was a circular ITO electrode with an area of 1.13 cm² and a guard ring. The orientation layers were lecithin for homeotropic orientation (ε| |) and polyimide AL-1054 from Japan Synthetic Rubber for homogenous orientation (ε±). The capacities were determined with a frequency response analyser Solatron 1260 using a sine wave with a voltage of 0.3 or 0.1 V_rms- The light used in the electro-optical measurements was white light. The set up used was a commercially available equipment of Otsuka, Japan. The characteristic voltages have been determined under perpendicular observation. The threshold voltage (V10), mid-grey voltage (V₅o) and saturation voltage (V_go) have been determined for 10 %, 50 % and 90 % relative contrast, respectively.

The mesogenic modulation material has been filled into an electro optical test cell prepared at the respective facility of Merck KGaA. The test cells had inter-digital electrodes on one substrate side. The electrode width was 10 μm, the distance between adjacent electrodes was 10μm and the cell gap was also 10 μm. This test cell has been evaluated electro-optically between crossed polarisers.

At low temperatures, the filled ceils showed the typical texture of a chiral nematic mixture, with an optical transmission between crossed polarisers without applied voltage. Upon heating, at a first temperature (T the mixtures turned optically isotropic, being dark between the crossed polarisers. This indicated the transition from the chiral nematic phase to the blue phase at that temperature. Up to a second temperature (T₂) the cell showed an electro-optical effect under applied voltage, typically of some tens of volts, a certain voltage in that range leading to a maximum of the optical transmission. Typically at a higher temperature the voltage needed for a visible electro-optical effect increased strongly, indicating the transition from the blue phase to the isotropic phase at this second temperature (T₂). The temperature range (ΔT(BP)), where the mixture can be used electro- optically in the blue phase most beneficially has been identified as ranging from Ti to T₂. This temperature range (ΔT(BP)) is the temperature range given in the examples of this application. The electro-optical displays can also be operated at temperatures beyond this range, i.e. at temperatures above T₂, albeit only at significantly increased operation voltages.

The liquid crystal media according to the present invention can contain further additives and chiral dopants in usual concentrations. The total concentration of these further constituents is in the range of 0 % to 10 %, preferably 0.1 % to 6 %, based in the total mixture. The concentrations of the individual compounds used each are preferably in the range of 0.1 to 3 %. The concentration of these and of similar additives is not taken into consideration for the values and ranges of the concentrations of the liquid crystal components and compounds of the liquid crystal media in this application.

The inventive liquid crystal media according to the present invention consist of several compounds, preferably of 3 to 30, more preferably of 5 to 20 and most preferably of 6 to 14 compounds. These compounds are mixed in conventional way. As a rule, the required amount of the compound used in the smaller amount is dissolved in the compound used in the greater amount. In case the temperature is above the clearing point of the compound used in the higher concentration, it is particularly easy to observe completion of the process of dissolution. It is, however, also possible to prepare the media by other conventional ways, e. g. using so called pre-mixtures, which can be e. g. homologous or eutectic mixtures of compounds or using so called multi-bottle-systems, the constituents of which are ready to use mixtures themselves.

By addition of suitable additives, the liquid crystal media according to the instant invention can be modified in such a way, that they are usable in all known types of liquid crystal displays, either using the liquid crystal media as such, like TN-, TN-AMD, ECB-, VAN-AMD and in particular in compo- site systems, like PDLD-, NCAP- and PN-LCDs and especially in HPDLCs. The melting point T(C,N), the transition from the smectic (S) to the nematic (N) phase T(S,N) and the clearing point T (N,l) of the liquid crystals are given in degrees centigrade.

In the present application and especially in the following examples, the structures of the liquid crystal compounds are represented by abbreviations also called acronyms. The transformation of the abbreviations into the corresponding structures is straight forward according to the following two tables A and B. All groups C_nH_2n+1 and C_mH_2m+ι are straight chain alkyl groups with n respectively m D-atoms. The interpretation of table B is self evident. Table A does only list the abbreviations for the cores of the structures. The individual compounds are denoted by the abbreviation of the core followed by a hyphen and a code specifying the substituents R , R2, Li and L≥ follows:

nOm C_nH_2n+ι OC_mH₂m+1 H H nO.m OC_nH_2n+ι C_mH_2m+i H H n C_nH_2n+ι CN H H nN.F C_nH_2n+ι CN H F nN.F.F C_nH_2n+ι CN F F nF C_nH_2n+ι F H H nF.F C_nH_2n+ι F H F nF.F.F C_nH_2n+ι F F F nOF OC_nH2n+1 F H H

nOCF₃.F C_nH_2n+ι OCF₃ H F nOCFg.F.F C_nH_2n+ι OCF3 F F

nOCF₂.F C_nH2n+1 OCHF₂ H F nOCF₂.F.F C_nH_2n+ι OCHF2 F F nS C_nH_2n+ι NCS H H nS.F C_nH_2n+ι NCS H F nS.F.F C_nH_2n+ι NCS F F rVsN C_rH_2r+-|-CH=CH-C₃H₂s" CN H H rEsN C_rH_2r+rO-C₃H _s- CN H H nAm C_nH_2n+ι COOC_mH₂m+ι H H nF.CI C_nH_2n+ι CI H F

PCH EPCH

BCH CCP

CECP ECCP

BECH EBCH

PTP CPTP

CEPTP

CCH PDX

PYP PYRP

ME

HP CP

EHP

ET

FET

Table B:

CGP-n-X CGG-n-X

(X = F, CF3, OCHF2 or OCF3) (X = F, CF3, OCHF2 or OCF3)

CGU-n-X B-nO.FN

(X = F, CF3, OCHF2 or OCF3)

CB15 C15

CBC-nm

CBC-nmF

K3n M3n

PG-n-AN

PU-n-AN

PPYRP-nN

PPYP-nN

PGP-n-N

PGIP-n-N

PVG-n-S

PVG-nO-S

PVG-V-S

PVG-nV-S

PVG-Vn-S

PPVU-n-S

CPVP-n-N

PTP-n(0)-S

PTG-n(0)-S

PTU-n(0)-S

PTPG-n(0)-N

GGP-n-CL

PGIGI-n-CL

CGU-n-F

PPU-n-S

^Cπ^H2 2nn++11 o ) — ( o > — ( o Wcs

PGU-n-S

BB3 n

c_nH_2n+1— < O W O V-C≡CW O V-C_mH_2m+1

PPTUI-n-m

C_nH_2n+1 — ( O h-COO ( O >— CN

F

GZU-n-N

GZU-nO-N

GZU-nA-N

UZU-n-N

UZU-nO-N

UZU-nA-N

CUZU-n-N

BCH-n.Fm

CFU-n-F

CBC-nmF

C_nH_2n+1 -X -^ ^cΛ^{" θ})- ^C™m^H 2m+1

ECCP-nm

CCZU-n-F

T-nFm

CGU-n-F

CGU-n-F

PUQU-n-OT

PUQU-n-T

PUZU-n-F

PGU-n-F

AUZU-n-F

AUZU-n-N

CGZP-n-OT

CCGU-n-F

CCQG-n-F

CUQU-n-F

CCCQU-n-F

AGUQU-n-F

AUUQU-n-F

AUUQU-n-N

CUUQU-n-F

CUUQU-n-OT

GZU-nA-N

UZU-nA-N

AUUQU-n-OT

AUUQU-n-T

AUUQP-n-T

AUUQGU-n-F

AUUQPU-n-F

CUZP-nN.F.F

GZU-nO-N

Particular preference is given to liquid-crystalline mixtures which, besides the compounds of the formula I, comprise at least one, two, three or four compounds from Table B. Table C:

Table C shows possible dopants according to component D which are generally added to the mixtures alone or in combination two, three or more) according to the invention.

C 15

CB 15

CM 21

R/S-811

C₃H₇ H )— H }— { O )- CH₂-CH-C₂H₅

CH,

CM 44

CM 45

CM 47

R/S-1011

R/S-3011

R/S-2011

R/S-4011

R/S-5011

IS-11480

IS-11489

IS-11663

IS-11851 Table D

Stabilisers which can be added, for example, to the mixtures according to the invention are mentioned below.

Hθ-/θ -CH₂— ~ -0H

H₃₇C₁₈-COO-C₂H₄-→ O V-OH

35

The liquid crystal media according to the instant invention do contain preferably

- four or more compounds selected from the group of compounds of tables A and B and/or

- five or more compounds selected from the group of compounds of table B and/or

- two or more compounds selected from the group of compounds of table A.

Examples

The examples given in the following are illustrating the present invention without limiting it in any way.

However, the physical data especially of the compounds illustrate to the expert which properties can be achieved in which ranges. Especially the combination of the various properties which can be preferably achieved is thus well defined.

Example 1

Preparation of 4'-Octyloxy-biphenyl-4-carboxylic acid bis- pentafluorophenyl-methyl ester

4'-Octyloxybiphenylcarboxylic acid (4.48 g, 13.7 mmol), decafluorobenzhydrol (5.00 g, 13.7 mmol), dicyclohexylcarbodiimide (DCC) (2.83 g, 13.7 mmol), dimethylaminopyridine (0.1 g) and dichloromethane (40 ml) were charged into a round-bottomed flask and stirred under nitrogen for 16 hours. The precipitate of dicyclohexyl urea (DCU) was removed by filtration and the filtrate was washed with water then dried over sodium sulphate. The solvent was removed and the resulting white solid was purified by flash column chromatography eluting with a 4:1 mixture of petrol (b.p. 40-60°C): DCM to yield 7.15 g, (77.1%) of white solid. GCMS showed a peak for the molar mass (M⁺) at 672 g/mole. The structure of the product was confirmed by ¹H NMR spectroscopy. yielded a phase sequence of: K-113-1 was observed by optical microscopy. Example 2

Preparation of 2'-Fluoro-4'-pentyl-biphenyl-4-carboxylic acid bis- pentafluorophenyl-methyl ester

4'-Pentyl-2'-fluorobiphenylcarboxylic acid (3.93 g, 13.7 mmol), decafluorobenzhydrol ( 5.00 g, 13.7 mmol), dicyclohexylcarbodiimide (DCC) (2.83 g, 13.7 mmol), dimethylaminopyridine (0.1 g) and dichloromethane (40 ml) were charged into a round bottomed flask and stirred under nitrogen for 18 hours. The precipitate of dicyclohexyl urea (DCU) was removed by filtration and the filtrate was washed with water then dried over sodium sulphate. The solvent removed and the resulting white solid was purified by flash column chromatography eluting with a 9:1 mixture of petrol (b.p. 40-60°C): DCM to yield 6.30 g (72.7%) of white solid. GCMS showed M⁺ at 632 g/mole. The structure of the product was confirmed by ¹H NMR spectroscopy. A phase sequence of : K-86.8-I was observed by optical microscopy.

Example 3

Preparation of 4'-Octyloxy-biphenyl-4-carboxylic acid 1 ,1-bis-(4-fluoro- phenyl)-methyl ester

4'-OctyloxybiphenylcarboxyIic acid (7.41 g, 22.7 mmol), decafluorobenzhydrol (5.00 g, 22.7 mmol), dicyclohexylcarbodiimide (DCC) (4.69 g, 22.7 mmol), dimethylaminopyridine (0.1 g) and dichloromethane (40 ml) were charged into a round-bottomed flask and stirred under nitrogen for 16 hours. The precipitate of dicyclohexyl urea (DCU) was removed by filtration and the filtrate washed with water then dried over sodium sulphate. The solvent was removed and the resulting white solid was purified by flash column chromatography eluting with a 4:1 mixture of petrol (b.p. 40-60°C):DCM to yield 8.10 g (67.5 %) of white solid. GCMS showed M⁺ = 529 g/mole. The structure of the product was confirmed by ¹H NMR spectroscopy. A phase sequence of: K-84-I was observed by optical microscopy.

Example 4

Preparation of 4'-(4-Pentyl-cyclohexyl)-biphenyl-4-carboxylic acid 1 ,1 -bis- (4-fluoro-phenyl)-methyl ester

4"-Pentylcyclohexylbiphenylcarboxylic acid (7.96 g, 22.7 mmol), decafluorobenzhydrol ( 5.00 g, 22.7 mmol), dicyclohexylcarbodiimide

(DCC) (4.69 g, 22.7 mmol), dimethylaminopyridine (0.1 g) and dichloromethane (40 ml) were charged into a round-bottomed flask and stirred under nitrogen for 16 hours. A precipitate of dicyclohexyl urea (DCU) was removed by filtration and the filtrate was washed with water then dried over sodium sulphate. The solvent was removed and the resulting white solid was purified by flash column chromatography eluting with a 7:3 mixture of petrol (b.p. 40-60°C):DCM to yield 3.18 g, (25.2 %) of white solid. The structure of the product was confirmed by ¹H NMR spectroscopy. Optical microscopy yielded a phase sequence of: K-137.4-1. Example 5

Preparation of 4'-(2-Methyl-butyl)-biphenyl-4-carboxylic acid bis- pentafluorophenyl-methyl ester

(+)-4'-(2-methylbutyl)fluorobiphenylcarboxylic acid (3.69 g, 13.7 mmol), decafluorobenzhydrol ( 5.00 g, 13.7 mmol), dicyclohexylcarbodiimide (DCC) (2.83 g, 13.7 mmol), dimethylaminopyridine (0.1 g) and dichloromethane (40 ml) were charged into a round bottomed flask and stirred under nitrogen for 18 hours. The precipitate of dicyclohexyl urea (DCU) was removed by filtration and the filtrate washed with water then dried over sodium sulphate. The solvent removed and the resulting white solid was purified by flash column chromatography eluting with a 9:1 mixture of petrol (b.p. 40-60°C): DCM to yield 5.50 g (65.2%) of white solid. GCMS showed M⁺ = 614 g/mole. The structure of the product was confirmed by ¹H and ¹³C NMR spectroscopy. A phase sequence of K-75.5- I was observed by optical microscopy.

Example 6

Preparation of 2'-Fluoro-4'-pentyl-biphenyl-4-carboxylic acid 1 ,1-bis-(4- fluoro-phenyl)-methyl ester

4'-Pentyl-2'-fluorobiphenylcarboxylic acid (3.90 g, 13.6 mmol), 4,4- difluorobenzhydrol (3.00 g, 13.7 mmol), dicyclohexylcarbodiimide (DCC) (2.81 g, 13.6 mmol), dimethylaminopyridine (0.1 g) and dichloromethane (40 ml) were charged into a round bottomed flask and stirred under nitrogen for 18 hours. The precipitate of dicyclohexyl urea (DCU) was removed by filtration and the filtrate washed with water then dried over sodium sulphate. The solvent removed and the resulting white solid was purified by flash column chromatography eluting with a 2:1 mixture of petrol (b.p. 40-60°C): DCM to yield 5.20 g (78.1%) of white solid. The structure of the product was confirmed by ¹H NMR spectroscopy. A phase sequence of: K-74-I was observed by optical microscopy.

Example 7

Preparation of 4'-(2-Methyl-butyl)-biphenyl-4-carboxylic acid 1 ,1-bis-(4- fluoro-phenyl)-methyl ester

4'(+)-2-methylbutylbiphenylcarboxylic acid (3.66 g, 13.6 mmol), 4,4- difluorobenzhydrol ( 3.00 g, 13.7 mmol), dicyclohexylcarbodiimide (2.81 g, 13.6 mmol), dimethylaminopyridine (0.1 g) and dichloromethane (40 ml) were charged into a round bottomed flask and stirred under nitrogen for 18 hours. The precipitate of dicyclohexyl urea was removed by filtration and the filtrate washed with water then dried over sodium sulphate. The solvent was removed and the resulting white solid was purified by flash column chromatography eluting with a 2:1 mixture of petrol (b.p. 40-60°C): DCM to yield a white solid, which was further purified by re-crystallization from industrial methylated spirits to yield 4.23 g (66%) of the product. The structure of the product was confirmed by ¹H NMR spectroscopy. A phase sequence of: K-89.3-I was observed by optical microscopy. Example 8

Preparation of 4'-(2-Methyl-butyl)-biphenyl-4-carboxylic acid 1 ,1-diphenyl- methyl ester

4'(+)-2-methylbutylbiphenylcarboxylic acid (3.66 g, 13.6 mmol), benzhydrol (2.39 g, 12.9 mmol), dicyclohexylcarbodiimide (DCC) (3.37 g, 16.4 mmol), dimethylaminopyridine (0.1 g) and dichloromethane (50 ml) were charged into a round-bottomed flask and stirred under nitrogen for 18 hours. The precipitate of dicyclohexyl urea (DCU) was removed by filtration and the filtrate was washed with water then dried over sodium sulphate. The solvent was removed and the resulting white solid was purified by flash column chromatography eluting with a solution of 30% DCM in petrol (b.p. 40-60°C) to yield a white solid. Further column purification by the same method and final re-crystallized from industrial methylated spirits afforded 3.6 g of the target material (61%). The structure of the product was confirmed by ¹H NMR spectroscopy. A phase sequence of K-102-1 was observed by optical microscopy.

Example 9

Preparation of 2'-Fluoro-4'-pentyl-biphenyl-4-carboxylic acid bis-(bis- trifluoromethyl-phenyl)-methyl ester

4'-Pentyl-2'fluorobiphenyl carboxylic acid (1.50 g, 5.2 mmol), 3,3'5,5'- tetrakis(trifluoromethyl)benzhydrol (2.37 g, 5.2 mmol), dicyclohexylcarbodiimide (DCC) (1.08 g, 5.2 mmol), dimethylaminopyridine (0.1 g) and dichloromethane (50 ml) were charged into a round bottomed flask and stirred under nitrogen for 18 hours. The precipitate of dicyclohexyl urea (DCU) was removed by filtration and the filtrate was washed with water then dried over sodium sulphate. The solvent was removed and the resulting white solid was purified by flash column chromatography eluting with a solution of 1 :1 DCM: petrol (b.p. 40-60°C) to yield an oil which solidified on standing. The solid was re-crystallized from acetonitrile to remove a slight yellow colour, and gave upon standing white crystals which were collected by filtration. The structure of the product was confirmed by ¹H NMR spectroscopy. A phase sequence of: K-99-I was observed by optical microscopy. GCMS showed M⁺ = 724 g/mole.

Example 10

Preparation of 2'-Fluoro-4'-pentyl-biphenyl-4-carboxylic acid 1 -phenyl- 1 -(4- trifluoromethyl-phenyl)-methyl ester

4'-Pentyl-2'fluorobiphenyl carboxylic acid (3.90 g, 13.6 mmol), 3,3'5,5'- tetrakis(trifluoromethyl)benzhydrol (3.40 g, 13.5 mmol), dicyclohexylcarbodiimide (2.81 g, 13.6 mmol), dimethylaminopyridine (0.1 g) and dichloromethane (50 ml) were charged into a round bottomed flask and stirred under nitrogen for 16 hours. The precipitate of dicyclohexyl urea (DCU) was removed by filtration and the filtrate was washed with dilute hydrochloric acid, water then dried over sodium sulphate. The solvent was removed and the resulting white solid was purified by flash column o chromatography eluting with a solution of 1 % DCM in petrol (b.p. 40-60°C) to yield an extremely viscous oil. The structure of the product was confirmed by ¹H NMR spectroscopy.

Example 11 5

Preparation of 4'-(1 ,1-Diphenyl-methoxy)-biphenyl-4-carboxylic acid methyl ester

Bromodiphenylmethane (11.0 g, 44.5 mmol), 4'-hydroxybiphenyl carboxylic⁵ acid methylester (10.2 g, 44.5 mmol), potassium carbonate (7.1 g, 50.6 mmol) and acetone (40 ml) were stirred together and heated to reflux for 18 hours. The mixture was allowed to cool to room temperature, the solids were removed in vacuo and the filter pad was washed through with fresh acetone. Concentration gave the desired product. Purification was carried⁰ out by re-crystallisation from propan-2-ol, followed by re-crystallisation from a acetonitrile + tetrahydrofuran solvent mixture which yielded a white solid (800 mg). A phase sequence of K-139.9-1 was observed by optical microscopy. ¹H NMR showed expected signals. 5 Example 12

Preparation of 4'-(1 ,1-Diphenyl-methoxy)-biphenyl-4-carboxylic acid 4- cyano-3,5-difluoro-phenyl ester

4'-(1 ,1-Diphenyl-methoxy)-biphenyl-4-carboxylic acid methyl ester (9) (4.8 g, 12.2 mmol), potassium hydroxide (2.4 g, 42.6 mmol), methanol (40 ml) and water (3 ml) were stirred under reflux for 90 minutes. The reaction was allowed to cool to room temperature, the reaction was acidified with dilute hydrochloric acid, and the solid material was filtered off and washed well with water to afford the acid intermediate (14 g, 8.2 mmol). The acid intermediate (3.0 g, 7.9 mmol), 2,6-difluoro-4-hydroxy- benzonitrile (1.2 g, 7.9 mmol), dicyclohexylcarbodiimide (DCC) (2.44 g, 11.8 mmol), dimethylaminopyridine (0.2 g) and dichloromethane (40 ml) were charged into a round bottomed flask and stirred under nitrogen for 18 hours. The precipitate of dicyclohexyl urea was removed by filtration and the filtrate was washed with water then dried over sodium sulphate. The solvent was removed and the resulting white solid was purified by flash column chromatography eluting with a solution of 50% DCM in petrol (b.p. 40-60°C) to yield a white solid. Repeated column purification and final re-crystallisation from acetonitrile at -20°C gave 800 mg of the final material as a white solid (20%). The structure of the product was confirmed by ¹H NMR spectroscopy. A phase sequence of K-131 -I was observed by optical microscopy.

Example 13

Preparation of 4-(1 ,1-Diphenyl-methoxy)-2,4'-difluoro-biphenyl

Benzhydrol (5.71 g, 31 mmol), 2,4'-difluorobiphenol (6.40g, 31 mmol), DCC (6.40g, 31 mmol) and dimethylaminopyridine (0.1 g) were stirred in dichloromethane for 18 hours under nitrogen. The precipitate of dicyclohexyl urea was removed by filtration and the filtrate washed with water then dried over sodium sulphate. The solvent was removed and the resulting white solid was purified by flash column chromatography eluting with a 1 :1 mixture of petrol (b.p. 40-60°C): DCM to yield a white solid, which was further purified by re-crystallisation from industrial methylated spirits to yield 8.3 g (72%) of the product. The structure of the product was confirmed by ¹H NMR spectroscopy. A phase sequence of: K-106.1-1 was observed by optical microscopy.

Example 14

Preparation of 4-(1,1-Diphenyl-methoxy)-4'pentyltolane

Diphenylbromomethane (28.1 g, 113.5 mmol), 4-iodophenol (25.0 g, 113.6 mmol), potassium carbonate (20. Og, 142 mmol) and acetone were charged to a flask and stirred under reflux together for 12 hours. After cooling to room temperature, the inorganic solids were filtered off, and the filtrate was concentrated to afford 4-iodophenyl(diphenylmethyl) ether. 4-lodophenyl- (diphenylmethyl) ether (5.0 g, 12.9 mmol), 1 -ethynyl-4-pentylbenzene (2.45 g, 12.2 mmol), copper (I) iodide (0.1 g, 0.5 mmol), bis(triphenyl- phosphine) palladium (II) dichloride (0.375 g, 0.5 mmol), tetrahydrofuran (9 ml) and triethylamine (5 ml) were all added to a flask and heated at 45°C for 20 hours. After cooling to room temperature, the solids were filtered off and the filter pad was washed with dichloromethane. After acidification and water washings, the solution was dried with magnesium sulphate and concentrated. The impure material was purified by column chromatography through silica gel using a solution of 10% toluene in petrol (b.p. 40-60°). Final traces of colour were removed by re-crystallisation from petrol (b.p. 40-60°) / ethanol yielding a 1.3 g of a white solid (23%).The structure of the product was confirmed by ¹H NMR spectroscopy. A phase sequence of K-92.8-I was observed by optical microscopy.

Example 15

Preparation of 9H-Fluorene-9-carboxylic acid 4'-cyano-biphenyl-4-yl ester

9-Fluorenecarboxylic acid (5.00 g, 23.8 mmol), 4'-hydroxybiphenyl- carbonitrile (4.64 g, 23.8 mmol), dicyclohexylcarbodiimide (4.91 g, 23.8 mmol), dimethylaminopyridine (0.1 g) and dichloromethane (40 ml) were charged into a round-bottomed flask and stirred under nitrogen for 16 hours. The precipitate of dicyclohexyl urea was removed by filtration and the filtrate washed with water then dried over sodium sulphate. The solvent removed and the resulting white solid was purified by flash column chromatography eluting with a 3:2 mixture of petrol (b.p. 40-60°C):DCM to yield 5.90 g (64.0%) of white solid product. The structure of the product was confirmed by ¹H NMR spectroscopy. Optical microscopy yielded a phase sequence of: K -182 - 1.

Example 16

Preparation of 2,7-Di-tert-butyl-9H-fluorene-9-carboxylic acid 4'-cyano- biphenyl-4-yl ester

2,7-Di-tert-butylfluorene-9-carboxylic acid (4.00 g, 12.4 mmol), 4'- hydroxybiphenylcarbonitnle (2.42 g, 12.4 mmol), dicyclohexylcarbodiimide (DCC) (2.56 g, 12.4 mmol), dimethylaminopyridine (0.1 g) and dichloromethane (40 ml) were charged into a round-bottomed flask and stirred under nitrogen for 16 hours. The precipitate of dicyclohexyl urea (DCU) was removed by filtration and the filtrate washed with water then dried over sodium sulphate. The solvent removed and the resulting white solid was purified by flash column chromatography eluting with a 3:1 mixture of petrol (b.p. 40-60°C): DCM to yield 4.23 g (68.2%) of crispy white solid product. The structure of the product was confirmed by ¹H NMR spectroscopy. Optical microscopy yielded a phase sequence of: K-182-1

Example 17

Preparation of 9H-Xanthene-9-carboxylic acid 4'-cyano-biphenyl-4-yl ester

Xanthene-9-carboxylic acid (4.3 g, 19.0 mmol), 4'-hydroxybiphenyl- carbonitrile (3.61 g, 18.5 mmol), dicyclohexylcarbodiimide (5.39 g, 26.2 mmol), dimethylaminopyridine (0.1 g) and toluene (30 ml) were charged into a round-bottomed flask and stirred under nitrogen for 16 hours. The precipitate of dicyclohexyl urea was removed by filtration and the filtrate washed with water then dried over sodium sulphate. The solvent was removed and the resulting yellow solid was purified by flash column chromatography eluting with a 2:1 mixture of petroleum spirits (b.p. 40-60°C): DCM to yield an off white solid. Final purification by re-crystallisation from petroleum spirits (b.p. 40-60°C): IMS was performed to yield 3.2 g (41.7%) of a white solid product. The structure of the product was confirmed by 1H NMR spectroscopy. A phase sequence of K-114.2-1 was observed by optical microscopy.

Example 18

Preparation of 9H-Xanthene-9-carboxylic acid 2,4'-difluoro-biphenyl-4-yl ester

Xanthene-9-carboxylic acid (7.0 g, 30.9 mmol), 3-fluoro(4'-fluorophenyl)- phenol (6.06 g, 29.4 mmol), dicyclohexylcarbodiimide (7.70 g, 37.3 mmol), dimethylaminopyridine (0.1 g), dichloromethane (50 ml) and toluene (50 ml) were charged to a round-bottomed flask and stirred under nitrogen for 2 hours. The precipitate of dicyclohexyl urea was removed by filtration and the filtrate washed with water then dried over sodium sulphate. The solvent was removed and the resulting yellow solid was purified by flash column chromatography eluting with a 1:1 mixture of petroleum spirits (b.p. 40- 60°C): DCM to yield an off white solid which was re-crystallized from petroleum spirits (b.p. 40-60°): IMS to yield 9.2 g (72%) of white solid product. The structure of the product was confirmed by ¹H NMR spectroscopy. A phase sequence of K-123.2-1 was observed by optical microscopy.

Examples 19

Preparation of Diphenylcarbamic acid 4'-cyano-biphenyl-4-yl ester

Diphenylcarbamyl chloride (5.00 g, 21.6 mmol), 4'-cyanobiphenol (4.21 g, 21.6 mmol), triethylamine (21.6 mmol) and dichloromethane (60 ml) were stirred at room temperature over night. The mixture was poured in to dilute hydrochloric acid, the resulting two layers were separated. The chlorinated phase was washed with water, dried over sodium sulphate, and evaporated to dryness on to silica gel. The crude product was purified by flash column chromatography to yield an oil which crystallised on standing. This material was further purified by re-crystallisation from petrol/ethyl acetate to give a white crystalline solid. The structure was verified by ¹H NMR- spectroscopy. The phase sequence was K-111-1.

Example 20

Preparation of 9H-Fluorene-9-carboxylic acid 4'-[1 , 1 -dif luoro-1 -(3,4,5- trifluoro-phenoxy)-methyl]-3',5^,-difluoro-biphenyl-4-yl ester

Step 20.1

4-(2-Tetrahydropyranyloxy)phenylboronic acid (3.0 g, 13.5 mmol), bromo- intermediate (from Merck KGaA, Darmstadt) (5.3 g, 13.5 mmol), 2 molar sodium carbonate solution (16 ml, 67.6 mmol), dichloro-[1 ,1 '- bis(diphenylphosphino)ferrocene]palladium (ll) dichloromethane adduct (300 mg, 0.4 mmol) and 1 ,4-dioxane (35 ml) were charged to a 3-neck flask under an atmosphere of nitrogen, then stirred under reflux for 24 hours. The mixture was allowed to cool to room temperature, water (50 ml) and diethyl ether (100 ml) were added. The organic layer was removed, washed and dried over sodium sulphate, then evaporated to dryness yielding 5.2 g (79%) of the target intermediate.

Step 20.2

THP protected phenol intermediate (5.2 g, 10.7 mmol), pyridinium toluenesuiphonate (0.7 g, 2.8 mmol) and methanol (25 ml) were stirred under nitrogen at 35°C for 18 hours. The mixture was cooled and added to water (50 ml). A solid precipitate was removed by filtration, the solid was dried under yielding a beige solid (4.8 g, HPLC showed a purity of 96%). This compound was used without further purification in the next step.

Step 20.3

9H-Fluorene-9-carboxylic acid (1.26 g, 6.0 mmol), dimethylaminopyridine (0.3 g, 2.4 mmol) and toluene (10 ml) were charged to a 3-neck flask. The mixture was cooled in an ice bath. DCC (2.0 g, 9.8 mmol) in toluene (5 ml) was added followed by 4-(2-tetrahydropyranyloxy)phenylboronic acid (2.25 g, 5.6 mmol) in toluene (10 ml). After 30 minutes the mixture was allowed to warm to room temperature. After 2 hours, a precipitate of DCU was removed by filtration. The filtrate was evaporated to dryness under vacuum. The crude product was purified by flash column chromatography using 30% dichloromethane in petrol (40°-60°C) as eluant. Evaporation of the appropriate fractions gave a pale yellow material which was re- crystallised from acetonitrile to give a white material (2.0 g, 56%). The structure was confirmed by ¹H NMR spectroscopy. A phase sequence of K-134.7-1 was observed by optical microscopy.

Example 21

Preparation of 9H-Xanthene-9-carboxylic acid 4'-[1 ,1 -dif luoro-1 -(3,4,5- trifluoro-phenoxy)-methyl]-3',5'-difluoro-biphenyl-4-yl ester

Xanthene-9-carboxylic acid (1.47 g, 6.5 mmol), dimethylaminopyridine (0.3 g, 2.4 mmol) and toluene (10 ml) were stirred at 0-5°C under a nitrogen atmosphere. Dicyclohexylcarbodiimide (2.0 g, 9.8 mmol) in toluene(5 mi) was added, stirred for 5 minutes, followed by the phenol intermediate (prepared as described in the previous example) (2.5 g, 6.2 mmol) in toluene (10 ml) slowly with stirring. After 5 minutes the mixture was allowed to warm to room temperature. After 3 hours, a precipitate of DCU was removed. The filtrate was concentrated to dryness under vacuum. The crude material was purified by flash column chromatography through silica using 30% dichloromethane in petrol (40-60°) as eluant. Evaporation of the appropriate fractions followed by re-crystallised from petrol 40-60/ 1 PA (10:1) gave a white solid (2.2 g, 55%), HPLC 99.4%, the structure was confirmed by ¹NMR spectroscopy. The following phase sequence was observed by optical microscopy: K-118-I.

Example 22

Preparation of 4'-(1 ,1-Dicyclohexyl-methoxy)-4-[1 ,1 -dif luoro-1 -(3,4,5- trifluoro-phenoxy)-methyl]-3,5-difluoro-biphenyl

Dicyclohexyl methanol (2.00 g, 10.2 mmol), triphenylphosphine (2.81 g, 10.7 mmol) and the phenol intermediate (3.67 g, 9.2 mmol) (prepared as described in example 20.2) were dissolved in tetrahydrofuran (15 ml) and cooled to 5^eC. Diisopropylazodicarboxylate (2.32 g, 11.5 mmol) in THF (5 ml) was added dropwise over 5 minutes. The reaction mixture was allowed to warm to room temperature. Analysis by thin layer chromatography showed only a small conversion to the desired product. The mixture was placed in a sonic bath and sonicated for 50 minutes at 50^SC. The crude solution was absorbed on to silica and purified by flash column chromatography using 1 :9 DCM:petrol 40-60, evaporation of the appropriate fractions gave a glass-like material (1.4 g, 24%), HPLC 99.5%, the structure was confirmed by ¹NMR spectroscopy.

Example 23

Preparation of 2'-Fluoro-4'-pentyl-biphenyl-4-carboxylic acid 1 -cyclohexyl- 1-phenyl-methyl ester

Phenylcyclohexyl methanol (1.00 g, 5.3 mmol), 4'-pentylphenyl-3- fluorobenzoic acid (1.66 g, 5.8 mmol), dicyclohexlcarbodiimide (1.78 g, 8.6 mmol), dimethylaminopyridine (0.1 g) and toluene (30 ml) were stirred at room temperature for 3 hours. A solid precipitate was removed by filtration, the filtrate was purified by flash column chromatography to give a white solid (1.6 g, 67%) which showed expected signals by ¹H NMR.

Examples 24 to 54

Analogously to Examples 1 and 2 the following compounds are prepared:

No. R¹¹ γ11 γ12 Phases (T/°C)

26 π-C₃H₇ H H

27 n-C₄H₉ H H

28 /7-C₅H11 H H

29 CH₃O H H

30 /7-C₃H₇O H H

31 π-C₄H₉0 H H

32 CH₂=CH H H

33 E-CH₃-CH₂=CH H H

34 CH₂=CH-0 H H

35 CH₂=CH-CH₂0 H H

36 C₂H_δ F H

37 n-C₃H₇ F H

38 π-C₄H₉ F H

2 π-C₅Hn F H K 86.8 I

40 CH₃O F H

42 n-C₄H₉0 F H

43 CH₂=CH F H

44 E-CH₃-CH=CH F H No. R 11 Y 11 Y¹^ Phases (T/°C)

45 CH₂=CH-0 F H

46 CH₂=CH-CH₂0 F H

47 C₂H₅ F F

48 π-C₃H₇ F F

49 n-C₄H₉ F F

50 n-C₅Hn F F

51 CH₃0 F F

52 π-CsHyO F F

53 CH₂=CH F F

54 E-CH₃-CH=CH F F

55 CH₂=CH-0 F F

56 CH₂=CH-CH₂0 F F

Examples 57 to 89

Analogously to Examples 1 and 2 the following compounds are prepared:

58 π-C₃H₇ H H

59 /7-C4H₉ H H

60 π-C₅Hn H H

62 n-C₃H₇0 H H

63 n-C₄H₉0 H H

64 CH₂=CH H H

66 CH₂=CH-0 H H No. R¹¹ Y¹¹ Y¹² Phases (T/°C)

67 CH₂=CH-CH₂0 H H

68 C₂H_δ F H

69 n-C₃H₇ F H

70 n-C₄H₉ F H

71 π-C₅Hn F H

72 CH₃0 F H

73 π-C₃H₇0 F H

74 π-C₄H₉0 F H

75 CH₂=CH F H

76 E-CH₃-CH=CH F H

77 CH₂=CH-0 F H

78 CH₂=CH-CH₂0 F H

80 π-C₃H₇ F F

81 π-C₄H₉ F F

82 π-C₅Hn F F

84 n-C₃H₇0 F F

85 CH₂=CH F F

86 £-CH₃-CH=CH F F

87 CH₂=CH-0 F F

88 CH₂=CH-CH₂0 F F

Examples 89 to 120

Analogously to Examples 1 and 2 the following compounds are prepared:

No. R¹¹ γ11 Y¹² Phases (T/°C)

89 C₂H_δ H H

91 n-C H₉ H H

92 π-C₅Hn H H

93 CH₃O H H

94 /7-C₃H₇O H H

95 π-C H₉0 H H

96 CH₂=CH H H

98 CH₂=CH-0 H H

99 CH₂=CH-CH₂0 H H

101 n-C₃H₇ F H

102 π-C₄H₉ F H

103 n-C₅Hιι F H

104 CH₃O F H

105 π-C₃H₇0 F H

106 n-C₄H₉0 F H

107 CH₂=CH F H

108 E-CH₃-CH= CH F H

109 CH₂=CH-0 F H

110 CH₂=CH-CH₂0 F H

111 C₂H₅ F F

112 π-C₃H₇ F F

113 n-C₄H₉ F F

114 π-C₅Hn F F

115 CH₃O F , F

116 π-C₃H₇0 F F

117 CH₂=CH F F

118 E-CH₃-CH= CH F F

119 CH₂=CH-0 F F

120 CH₂=CH-CH₂0 F F Examples 121 to 152

Analogously to Examples 3 and 6 the following compounds are prepared:

No. R¹¹ _γπ Y¹^ Phases (T/°C)

121 C₂H₅ H H

122 /7-C₃H₇ H H

123 r?-C₄H₉ H H

124 π-C₅Hn H H

125 CH₃O H H

126 n-C₃H₇0 H H

127 n-C H₉0 H H

128 CH₂=CH H H

129 E-CH₃-CH₂=CH H H

130 CH₂=CH-0 H H

131 CH₂=CH-CH₂0 H H

132 C₂H₅ F H

133 n-C₃H₇ F H

134 π-C₄H₉ F H

135 n-CsHn F H K 74 I

136 CH₃O F H

137 π-C₃H₇0 F H

138 π-C H₉0 F H

139 CH₂=CH F H

140 E-CH₃-CH=CH F H

141 CH₂=CH-0 F H

142 CH₂=CH-CH₂0 F H

No. R 11 Y 11

Y1'2* Phases (T/°C)

145 t7-C₄H₉ F F

146 n-CsHn F F

147 CH₃0 F F

148 t7-C₃H₇0 F F

149 CH₂=CH F F

150 E-CH₃-CH=CH F F

151 CH₂=CH-0 F F

152 CH₂=CH-CH₂0 F F

Examples 152 to 183

Analogously to Examples 3 and 6 the following compounds are prepared:

11

No. R Y 11 Y /1"2 Phases (T/°C)

154 t7-C₄H₉ H H

155 π-C₅Hn H H

156 CH₃O H H

157 π-C₃H₇0 H H

158 n-C₄H₉0 H H

159 CH₂ ⁼CH H H

160 E-CH₃-CH₂=CH H H

161 CH₂=CH-0 H H

162 CH₂=CH-CH₂0 H H

165 π-C₄H₉ F H NO. R 11

Y 11 Y1¹2" Phases (T/°C)

166 n-C₅Hπ F H

167 CH₃0 F H

169 π-C₄H₉0 F H

170 CH₂=CH F H

171 E-CH₃-CH=CH F H

172 CH₂=CH-0 F H

173 CH₂=CH-CH₂0 F H

174 C₂H₅ F F

175 n-C₃H₇ F F

176 π-C₄H₉ F F

177 π-C₅Hιι F F

178 CH₃O F F

179 π-C₃H₇0 F F

180 CH₂=CH F F

181 E-CH₃-CH=CH F F

182 CH₂=CH-0 F F

183 CH₂=CH-CH₂0 F F

Examples 184 to 215

Analogously to Examples 3 and 6 the following compounds are prepared:

No. R 11 Y 11 ■12" Phases (T/°C)

184 C₂H₅ H H

185 n-C₃H₇ H H

186 n-C₄H₉ H H

187 π-CsHu H H No. R¹¹ γ11 Y¹² Phases (T/°C)

188 CH₃0 H H

189 n-C₃H₇0 H H

190 n-C₄H₉0 H H

191 CH₂=CH H H

192 E-CH₃-CH₂=CH H H

193 CH₂=CH-0 H H

194 CH₂=CH-CH₂0 H H

195 C₂H_δ F H

197 π-C₄H₉ F H

198 AT-CsHn F H

199 CH₃O F H

200 π-C₃H₇0 F H

201 n-C₄H₉0 F H

202 CH₂=CH F H

203 E-CH₃-CH=CH F H

204 CH₂=CH-0 F H

205 CH₂=CH-CH₂0 F H

207 n-C₃H₇ F F

208 π-C₄H₉ F F

209 π-C₅Hn F F

210 CH₃0 F F

211 n-C₃H₇0 F F

212 CH₂=CH F F

213 E-CH₃-CH=CH F F

214 CH₂=CH-0 F F

215 CH₂=CH-CH₂0 F F

Examples 216 to 246

Analogously to Example 4 the following compounds are prepared:

R" Y¹¹ Y¹^ Phases (T/°C) C₂H₅ H H π-C₃H₇ H H π-C₄H₉ H H n-C₅Hιι H H K 137.4 1 CH₃0 H H n-C₃H₇0 H H π-C₄H₉0 H H CH₂=CH H H E-CH₃-CH₂=CH H H CH₂=CH-0 H H CH₂=CH-CH₂0 H H C₂H₅ F H π-C₃H₇ F H n-C₄H₉ F H n-C₅Hn F H CH₃O F H

π-C₄H₉0 F H CH₂=CH F H E-CH₃-CH=CH F H CH₂=CH-0 F H CH₂=CH-CH₂0 F H C₂H₅ F F π-C₃H₇ F F A7-C₄H₉ F F n-C₅Hn F F CH₃O F F

No. R 11 Y 11

Y λl2 Phases (T/°C)

243 CH₂=CH F F

244 E-CH₃-CH=CH F F

245 CH₂=CH-0 F F

246 CH₂=CH-CH₂0 F F

Examples 247 to 278

Analogously to Example 4 the following compounds are prepared:

No. R¹¹ γiι Y¹^ Phases (T/°C)

247 C₂H_δ H H

248 n-C₃H₇ H H

249 π-C₄H₉ H H

250 n-C₅Hn H H

251 CH₃0 H H

252 π-C₃H₇0 H H

253 n-C₄H₉0 H H

254 CH₂=CH H H

256 CH₂=CH-0 H H

257 CH₂=CH-CH₂0 H H

258 C₂H_δ F H

259 π-C₃H₇ F H

260 n-C₄H₉ F H

261 n-CsHn F H

263 π-C₃H₇0 F H

264 n-C₄H₉0 F H No. R 11 Y 11 Y /1¹2 Phases (T/°C)

265 CH₂=CH F H

266 E-CH₃-CH=CH F H

267 CH₂=CH-0 F H

268 CH₂=CH-CH₂0 F H

269 C₂H_δ F F

270 π-C₃H₇ F F

271 n-C₄H₉ F F

272 n-C₅Hn F F

273 CH₃0 F F

274 n-C₃H₇0 F F

275 CH₂=CH F F

276 E-CH₃-CH=CH F F

277 CH₂=CH-0 F F

278 CH₂=CH-CH₂0 F F

Examples 279a 279q and 280 to 304 Analogously to Examples 3 and 6 the following compounds are prepared:

No. ^■.11 Y 11 Y ,1¹2^ Phases (T/°C)

279c n-C₄H₉ H H

279d n-C₅Hn H H

279e CH₃O H H

279f n-C₃H₇0 H H

279g π-C₄H₉0 H H

280 CH₂=CH H H No. R 11 Y 11 Y ,1¹^ Phases (T/°C)

281 E-CH₃-CH₂=CH H H

282 CH₂=CH-0 H H

283 CH₂=CH-CH₂0 H H

284 C₂H_δ F H

285 n-C₃H₇ F H

286 n-C₄H₉ F H

287 π-C₅Hn F H

288 CH₃0 F H

289 π-C₃H₇0 F H

290 tι-C₄H₉0 F H

291 CH₂=CH F H

292 E-CH₃-CH=CH F H

293 CH₂=CH-0 F H

294 CH₂=CH-CH₂0 F H

295 C₂H_δ F F

296 n-C₃H₇ F F

297 n-C₄H₉ F F

298 n-C₅Hn F F

299 CH₃O F F

300 n-C₃H₇0 F F

301 CH₂=CH F F

302 E-CH₃-CH=CH F F

303 CH₂=CH-0 F F

304 CH₂=CH-CH₂0 F F

Exam pies 305 to 356

Analogously to Example 8 the following compounds are prepared:

No. R¹¹ γ11 Y¹² Phases (T/°C)

305 C₂H_δ H H

306 π-C₃H₇ H H

307 n-C H₉ H H

308 π-C₅Hn H H

309 CH₃0 H H

310 n-C₃H₇0 H H

311 n-C H₉0 H H

312 CH₂=CH H H

313 E-CH₃-CH₂=CH H H

314 CH₂=CH-0 H H

315 CH₂=CH-CH₂0 H H

316 C₂H₅ F H

317 n-C₃H₇ F H

318 n-C₄H₉ F H

319 n-C₅Hn F H

320 CH₃O F H

331 n-C₃H₇0 F H

332 π-C₄H₉0 F H

333 CH₂=CH F H

334 E-CH₃-CH=CH F H

335 CH₂=CH-0 F H

336 CH₂=CH-CH₂0 F H

337 C₂H₅ F F

349 n-C H₉ F F

350 n-C₅Hn F F

351 CH₃0 F F

352 n-C₃H₇0 F F

353 CH₂=CH F F

354 E-CH₃-CH=CH F F

355 CH₂=CH-0 F F

356 CH₂=CH-CH₂0 F F Examples 357 to 388

Analogously to Example 8 the following compounds are prepared:

No. R¹¹ Y¹¹ γ« Phases (T/°C)

357 C₂H_δ H H

358 n-C₃H₇ H H

360 n-CsHn H H

361 CH₃0 H H

362 n-C₃H₇0 H H

363 π-C₄H₉0 H H

364 CH₂=CH H H

365 E-CH₃-CH₂= =CH H H

366 CH₂=CH-0 H H

367 CH₂=CH-CH₂0 H H

368 C₂H_δ F H

369 n-C₃H₇ F H

370 n-CMs F H

371 n-C₅Hιι F H

372 CH₃O F H

373 π-C₃H₇0 F H

374 n-C₄H₉0 F H

375 CH₂=CH F H

376 E-CH₃-CH=' CH F H

377 CH₂=CH-0 F H

378 CH₂=CH-CH₂0 F H

379 C₂H₅ F F

380 t7-C₃H₇ F F

381 π-C₄H₉ F F

382 n-C₅Hn F F No. ,11 Y 11

Y ,1'2* Phases (T/°C)

383 CH₃0 F F

384 π-C₃H₇0 F F

385 CH₂=CH F F

386 E-CH₃-CH=CH F F

387 CH₂=CH-0 F F

388 CH₂=CH-CH₂0 F F

Examples 389 to 420

Analogously to Example 8 the following compounds are prepared:

No. R¹¹ γiι Y¹^ Phases (T/°C)

389 C₂H₅ H H

390 n-C₃H₇ H H

391 π-C₄H₉ H H

392 n-C₅Hn H H

393 CH₃O H H

394 n-C₃H₇0 H H

395 n-C₄H₉0 H H

396 CH₂ ⁼CH H H

397 E-CH₃-CH₂=CH H H

398 CH₂=CH-0 H H

399 CH₂=CH-CH₂0 H H

400 C₂H₅ F H

401 π-C₃H₇ F H

402 n-C₄H₉ F H

403 n-C₅Hn F H

404 CH₃0 F H

405 n-C₃H₇0 F H

406 n-C H₉0 F H No. R¹¹ γi ι Y¹^ Phases (T/°C)

407 CH₂=CH F H

408 E-CH₃-CH=CH F H

409 CH₂=CH-0 F H

410 CH₂=CH-CH₂0 F H

412 n-C₃H₇ F F

413 n-C₄H₉ F F

414 n-C₅Hn F F

415 CH₃O F F

416 n-C₃H₇0 F F

417 CH₂=CH F F

418 E-CH₃-CH=CH F F

419 CH₂=CH-0 F F

420 CH₂=CH-CH₂0 F F

Examples 421 to 451

Analogously to Example 9 the following compounds are prepared:

No. R 11 ,11 Y /1¹2 Phases (T/°C)

422 π-C₃H₇ H H

423 π-C₄H₉ H H

424 π-C₅Hn H H

9 CH₃O H H

425 n-C₃H₇0 H H

426 π-C H₉0 H H

427 CH₂=CH H H

428 E-CH₃-CH₂=CH H H

429 CH₂=CH-0 H H No. R¹¹ Y¹¹ Y^ Phases (T/°C)

430 CH₂=CH-CH₂0 H H

431 C₂H_δ F H

432 n-C₃H₇ F H

433 π-C₄H₉ F H

434 π-C₅Hn F H

435 CH₃0 F H

436 π-C₃H₇0 F H

437 n-C₄H₉0 F H

438 CH₂=CH F H

439 E-CH₃-CH=CH F H

440 CH₂=CH-0 F H

441 CH₂=CH-CH₂0 F H

443 n-C₃H₇ F F

444 n-C₄H₉ F F

445 π-C₅Hn F F

447 n-C₃H₇0 F F

448 CH₂=CH F F

449 E-CH₃-CH=CH F F

450 CH₂=CH-0 F F

451 CH₂=CH-CH₂0 F F

Examples 452 to 483

Analogously to Example 9 the following compounds are prepared:

No. R¹¹ γ11 γ12 Phases (T/°C)

453 n-C₃H₇ H H

454 n-C₄H₉ H H

455 n-C₅Hn H H

456 CH₃0 H H

457 /7-C₃H₇O H H

458 π-C₄H₉0 H H

459 CH₂=CH H H

460 E-CH₃-CH₂=CH H H

461 CH₂=CH-0 H H

462 CH₂=CH-CH₂0 H H

464 n-C₃H₇ F H

465 π-C₄H₉ F H

466 n-C₅Hιι F H

467 CH₃0 F H

468 n-C₃H₇0 F H

469 A7-C₄H₉0 F H

470 CH₂=CH F H

471 E-CH₃-CH=CH F H

472 CH₂=CH-0 F H

473 CH₂=CH-CH₂0 F H

474 C₂H₅ F F

475 r?-C₃H₇ F F

476 π-C₄H₉ F F

477 n-C₅Hn F F

478 CH₃O F F

479 π-C₃H₇0 F F

480 CH₂=CH F F

481 E-CH₃-CH=CH F F

482 CH₂=CH-0 F F

483 CH₂=CH-CH₂0 F F Examples 484 to 515

Analogously to Example 9 the following compounds are prepared:

485 π-C₃H₇ H H

486 π-C₄H_g H H

487 n-CsHn H H

488 CH₃0 H H

489 π-C₃H₇0 H H

490 n-C₄H₉0 H H

491 CH₂=CH H H

493 CH₂=CH-0 H H

494 CH₂=CH-CH₂0 H H

497 n-C₄H₉ F H

498 π-C₅Hn F H

569 CH₃0 F H

500 n-C₃H₇0 F H

501 n-C₄H₉0 F H

502 CH₂=CH F H

503 E-CH₃-CH= CH F H

504 CH₂=CH-0 F H

505 CH₂=CH-CH₂0 F H

507 n-C₃H₇ F F

508 π-C₄H₉ F F

509 n-C₅Hn F F NO. R 11 Y 11 Y /1¹2^ Phases (T/°C)

510 CH₃0 F F

511 /7-C₃H₇O F F

512 CH₂=CH F F

513 E-CH₃-CH=CH F F

514 CH₂=CH-0 F F

515 CH₂=CH-CH₂0 F F

Examples 516 to 774

Analogously to Example 10 the following compounds are prepared:

No. R 11 γ11 γ12 γ13 γ14 γ1 γ16 p_hases (_T/°_C)

516 CN H H H H H H

517 NCS H H H H H H

518 F H H H H H H

519 CI H H H H H H

520 CF₃ H H H H H H

522 CH₃ H H H H H H

523 CH₃O H H H H H H

524 CH₂=CH H H H H H H

525 CH₂=CH-0 H H H H H H

526 CN F H H H H H

527 NCS F H H H H H

528 F F H H H H H

529 CI F H H H H H

530 CF₃ F H H H H H

532 CH₃ F H H H H H

533 CH₃0 F H H H H H No. R 11 γ11 γ12 γ13 γ14 _γ1δ _γ16 p_{hases (T/}°_C)

534 CH₂=CH F H H H H H

535 CH₂=CH-0 F H H H H H 536 CN H H F H H H

537 NCS H H F H H H

538 F H H F H H H

539 CI H H F H H H

540 CF₃ H H F H H H 541 OCF₃ H H F H H H

542 CH₃ H H F H H H

544 CH₂=CH H H F H H H

545 CH₂=CH-0 H H F H H H 546 CN H H H H F H

547 NCS H H H H F H

548 F H H H H F H

549 CI H H H H F H

550 CF₃ H H H H F H

553 CH₃O H H H H F H

554 CH₂=CH H H H H F H

555 CH₂=CH-0 H H H H F H 556 CN F H F H H H

557 NCS F H F H H H

558 F F H F H H H

559 CI F H F H H H

560 CF₃ F H F H H H

562 CH₃ F H F H H H

563 CH₃O F H F H H H

564 CH₂=CH F H F H H H

565 CH₂=CH-0 F H F H H H 566 CN F H H H F H

567 NCS F H H H F H

568 F F H H H F H NO. R 11 _γ11 γ12 _γ13 _γ14 γ15 γ1^β p_{hasΘS (T/}°_C)

569 CI F H H H F H

570 CF₃ F H H H F H

571 OCF₃ F H H H F H

572 CH₃ F H H H F H

573 CH₃O F H H H F H

574 CH₂=CH F H H H F H

575 CH₂=CH-0 F H H H F H

576 CN H H F H F H

577 NCS H H F H F H

578 F H H F H F H

579 CI H H F H F H

580 CF₃ H H F H F H 581 OCF₃ H H F H F H

582 CH₃ H H F H F H

583 CH₃O H H F H F H

584 CH₂=CH H H F H F H

585 CH₂=CH-0 H H F H F H

586 CN F H F H F H

587 NCS F H F H F H

588 F F H F H F H

589 CI F H F H F H

590 CF₃ F H F H F H

592 CH₃ F H F H F H

593 CH₃O F H F H F H

594 CH₂=CH F H F H F H

595 CH₂=CH-0 F H F H F H 10 CN F F H H H H

596 NCS F F H H H H

597 F F F H H H H

598 CI F F H H H H

599 CF₃ F F H H H H

601 CH₃ F F H H H H

602 CH₃O F F H H H H LL LL

X

X LL LL

LL N CO CO

IΩ O IO O

IO CM CM CO CO

No. R¹¹ γ11 γ12 γ13 γ14 γ15 γ16 Phases (T/°C)

638 CI F F H H F F

649 CF₃ F F H H F F

640 OCF₃ F F H H F F

641 CH₃ F F H H F F

642 CH₃0 F F H H F F

643 CH₂=CH F F H H F F

644 CH₂=CH-0 F F H H F F

645 CN H H F F F F

646 NCS H H F F F F

647 F H H F F F F

648 CI H H F F F F

649 CF₃ H H F F F F

651 CH₃ H H F F F F

652 CH₃O H H F F F F

653 CH₂=CH H H F F F F

654 CH₂=CH-0 H H F F F F

655 CN F F F F F F

656 NCS F F F F F F

657 F F F F F F F

658 CI F F F F F F

659 CF₃ F F F F F F

661 CH₃ F F F F F F

662 CH₃O F F F F F F

663 CH₂=CH F F F F F F

664 CH =CH-0 F F F F F F

665 CN F F F H H H

666 NCS F F F H H H

667 F F F F H H H

668 CI F F F H H H

669 CF₃ F F F H H H

671 CH₃ F F F H H H

672 CH₃O F F F H H H No. R¹¹ γ11 γ12 _γ13 γ14 γ15 Y¹

673 CH₂=CH F F F H H H

674 CH₂=CH-0 F F F H H H

675 CN F F H H H F

676 NCS F F H H F H

677 F F F H H F H

678 CI F F H H F H

679 CF₃ F F H H F H

680 OCF₃ F F H H F H

681 CH₃ F F H H F H

682 CH₃O F F H H F H

683 CH₂=CH F F H H F H

684 CH₂=CH-0 F F H H F H

685 CN F H F F H H

686 NCS F H F F H H

687 F F H F F H H

688 CI F H F F H H

689 CF₃ F H F F H H

691 CH₃ F H F F H H

692 CH₃O F H F F H H

693 CH₂=CH F H F F H H

694 CH₂=CH-0 F H F F H H

695 CN H H F F F H

696 NCS H H F F F H

697 F H H F F F H

698 CI H H F F F H

699 CF₃ H H F F F H

701 CH₃ H H F F F H

702 CH₃Q H H F F F H

703 CH₂=CH H H F F F H

704 CH₂=CH-0 H H F F F H

705 CN F H H H F F

706 NCS F H H H F F

707 F F H H H F F No. R¹¹ γ11 γ12 γ13 γ1 γ15 Y 16 Phases (T/°C)

708 CI F H H H F F

709 CF₃ F H H H F F

710 OCF₃ F H H H F F

711 CH₃ F H H H F F

712 CH₃0 F H H H F F

713 CH₂=CH F H H H F F

714 CH₂=CH-0 F H H H F F

715 CN H H F H F F

716 NCS H H F H F F

717 F H H F H F F

718 CI H H F H F F

719 CF₃ H H F H F F

720 OCF₃ H H F H F F

721 CH₃ H H F H F F

722 CH₃0 H H F H F F

723 CH₂=CH H H F H F F

724 CH₂=CH-0 H H F H F F

725 CN F F F H F H

726 NCS F F F H F H

727 F F F F H F H

728 CI F F F H F H

729 CF₃ F F F H F H

731 CH₃ F F F H F H

732 CH₃O F F F H F H

733 CH₂=CH F F F H F H

734 CH₂=CH-0 F F F H F H

735 CN F H F F F H

736 NCS F H F F F H

737 F F H F F F H

738 CI F H F F F H

739 CF₃ F H F F F H

741 CH₃ F H F F F H

742 CH₃0 F H F F F H No. R¹¹ γ11 γ12 γ13 γ14 γ15 Y 16

743 CH₂=CH F H F F F H

744 CH₂=CH-0 F H F F F H

745 CN F H F H F F

746 NCS F H F H F F

747 F F H F H F F

748 CI F H F H F F

749 CF₃ F H F H F F

750 OCF₃ F H F H F F

751 CH₃ F H F H F F

752 CH₃O F H F H F F

753 CH₂=CH F H F H F F

754 CH₂=CH-0 F H F H F F

765 CN F F F F F H

766 NCS F F F F F H

767 F F F F F F H

768 CI F F F F F H

769 CF₃ F F F F F H

771 CH₃ F F F F F H

772 CH₃O F F F F F H

773 CH₂=CH F F F F F H

774 CH₂=CH-0 F F F F F H

775 CN F F F H F F

776 NCS F F F H F F

777 F F F F H F F

778 CI F F F H F F

779 CF₃ F F F H F F

781 CH₃ F F F H F F

782 CH₃O F F F H F F

783 CH₂=CH F F F H F F

784 CH₂=CH-0 F F F H F F

785 CN F H F F F F

786 NCS F H F F F F

787 F F H F F F F No. R 11 Y ,^•1"1 χ Y_/1¹3^J Y1¹4⁴ N Y/1¹5⁰ χ Y_/1¹6^P Phases (T/°C)

788 CI F H F F F F

789 CF₃ F H F F F F

790 OCF₃ F H F F F F

791 CH₃ F H F F F F

792 CH₃0 F H F F F F

793 CH₂=CH F H F F F F

794 CH₂=CH-0 F H F F F F

Examples 795 to 854

Analogously to Example 12 the following compounds are prepared:

No. R¹¹ γ11 γ12 γ13 Y¹⁴ Phases (T/°C)

795 CN H H H H

796 NCS H H H H

797 F H H H H

798 CI H H H H

799 CF₃ H H H H

800 OCF₃ H H H H

801 CH₃ H H H H

802 CH₃0 H H H H

803 CH₂=CH H H H H

804 CH₂=CH-0 H H H H

805 CN F H H H

806 NCS F H H H

807 F F H H H

808 CI F H H H

809 CF₃ F H H H

811 CH₃ F H H H

812 CH₃0 F H H H

813 CH₂=CH F H H H

814 CH₂=CH-0 F H H H

815 CN H H F H

816 NCS H H F H

817 F H H F H

818 CI H H F H

819 CF₃ H H F H

821 CH₃ H H F H

822 CH₃O H H F H

823 CH₂=CH H H F H

824 CH₂=CH-0 H H F H

825 CN F H F H

826 NCS F H F H

827 F F H F H

828 CI F H F H

829 CF₃ F H F H

831 CH₃ F H F H

832 CH₃O F H F H

833 CH₂=CH F H F H

834 CH₂=CH-0 F H F H

835 CN F F H H

836 NCS F F H H

837 F F F H H

838 CI F F H H

839 CF₃ F F H H

841 CH₃ F F H H

842 CH₃O F F H H

843 CH₂=CH F F H H

844 CH₂=CH-0 F F H H

845 CN H H F F

846 NCS H H F F No. 11 y ,1n1 χ _γ/1^2 χ _γ/1₁3 _γ1i44 p_{hases (T}/o_C)

847 F H H F F

848 CI H H F F

849 CF₃ H H F F

840 OCF₃ H H F F

851 CH₃ H H F F

852 CH₃0 H H F F

853 CH₂=CH H H F F

854 CH₂=CH-0 H H F F

845 CN F F F H

846 NCS F F F H

847 F F F F H

848 CI F F F H

849 CF₃ F F F H

850 OCF₃ F F F H

851 CH₃ F F F H

852 CH₃0 F F F H

853 CH₂=CH F F F H

854 CH₂=CH-0 F F F H

855 CN F H F F

856 NCS F H F F

857 F F H F F

858 CI F H F F

859 CF₃ F H F F

861 CH₃ F H F F

862 CH₃0 F H F F

863 CH₂=CH F H F F

864 CH₂=CH-0 F H F F

865 CN F F F F

866 NCS F F F F

867 F F F F F

868 CI F F F F

869 CF₃ F F F F

861 CH₃ F F F F NO. R 11 Y ,1"1 _γ ,1^2 _{γ γ} 14 p_haSΘS (_T/°c)

862 CH₃0 F F F F

863 CH₂=CH F F F F

864 CH₂=CH-0 F F F F

Examples 855 to 934

Analogously to Example 12 the following compounds are prepared:

No. R ,11 11 12 13 14 Phases (T/°C)

855 CN F H H H 856 NCS F H H H 857 F F H H H 858 CI F H H H 859 CF₃ F H H H 860 OCF₃ F H H H 861 CH₃ F H H H 862 CH₃0 F H H H 863 CH₂=CH F H H H 864 CH₂=CH-0 F H H H 865 CN H H F H 866 NCS H H F H 867 F H H F H 868 CI H H F H 869 CF₃ H H F H

871 CH₃ H H F H 872 CH₃0 H H F H 873 CH₂=CH H H F H 874 CH₂=CH-0 H H F H 875 CN F H F H No. R¹¹ L¹¹ L¹² _L13 L¹⁴ Phases (T/°C)

876 NCS F H F H

877 F F H F H

878 CI F H F H

879 CF₃ F H F H

880 OCF₃ F H F H

881 CH₃ F H F H

883 CH₂=CH F H F H

884 CH₂=CH-0 F H F H

885 CN F F H H

886 NCS F F H H

887 F F F H H

888 CI F F H H

889 CF₃ F F H H

890 OCF₃ F F H H

891 CH₃ F F H H

892 CH₃O F F H H

893 CH₂=CH F F H H

894 CH₂=CH-0 F F H H

895 CN H H F F

896 NCS H H F F

897 F H H F F

898 CI H H F F

899 CF₃ H H F F

900 OCF₃ H H F F

901 CH₃ H H F F

902 CH₃0 H H F F

903 CH₂=CH H H F F.

904 CH₂=CH-0 H H F F

905 CN F F F H

906 NCS F F F H

907 F F F F H

908 CI F F F H

909 CF₃ F F F H

910 OCF₃ F F F H No. R 11 11 12 13 14 Phases (T/°C)

911 CH₃ F F F H 912 CH₃0 F F F H 913 CH₂=CH F F F H 914 CH₂=CH-0 F F F H 915 CN F H F F 916 NCS F H F F 917 F F H F F 918 CI F H F F 919 CF₃ F H F F 920 OCF₃ F H F F 921 CH₃ F H F F 922 CH₃O F H F F 923 CH =CH F H F F 924 CH₂=CH-0 F H F F 925 CN F F F F 926 NCS F F F F 927 F F F F F 928 CI F F F F 929 CF₃ F F F F 930 OCF₃ F F F F 931 CH₃ F F F F

933 CH₂=CH F F F F 934 CH₂=CH-0 F F F F

Examples 935 to 1023 Analogously to Example 13 the following compounds are prepared:

R¹¹ γ11 γ12 γ13 Y ¹⁴ Phases (T/°C)

CN H H H H

NCS H H H H

F H H H H

CI H H H H

CF₃ H H H H

OCF₃ H H H H

CH₃ H H H H

CH₃O H H H H

CH₂=CH H H H H

CH₂=CH-0 H H H H

CN F H H H

NCS F H H H

F F H H H

CI F H H H

CF₃ F H H H

OCF₃ F H H H

CH₃ F H H H

CH₃0 F H H H

CH₂=CH F H H H

CH₂=CH-0 F H H H

CN H H F H

NCS H H F H

F H H F H

CI H H F H

CF₃ H H F H

CH₃ H H F H

CH₃O H H F H

CH₂=CH H H F H

CH₂=CH-0 H H F H

CN F H F H

NCS F H F H

F F H F H

CI F H F H

CF₃ F H F H

969 OCF₃ F H F H

970 CH₃ F H F H

971 CH₃O F H F H

972 CH₂=CH F H F H

973 CH₂=CH-0 F H F H

974 CN F F H H

975 NCS F F H H

976 F F F H H

977 CI F F H H

978 CF₃ F F H H

980 CH₃ F F H H

981 CH₃O F F H H

982 CH₂=CH F F H H

983 CH₂=CH-0 F F H H

984 CN H H F F

985 NCS H H F F

986 F H H F F

987 CI H H F F

988 CF₃ H H F F

990 CH₃ H H F F

991 CH₃O H H F F

992 CH₂=CH H H F F

993 CH₂=CH-0 H H F F

994 CN F F F H

995 NCS F F F H

996 F F F F H

997 CI F F F H

998 CF₃ F F F H

1000 CH₃ F F F H

1001 CH₃0 F F F H

1002 CH₂=CH F F F H

1003 CH₂=CH-0 F F F H No. R 11 Y ,1"1 _v Y1'2 _\ Y1^l3^ύ χ Y_/1¹4⁴ Phases (T/°C)

1004 CN F H F F

1005 NCS F H F F

1006 F F H F F

1007 CI F H F F

1008 CF₃ F H F F

1009 OCF₃ F H F F

1010 CH₃ F H F F

1011 CH₃0 F H F F

1012 CH₂=CH F H F F

1013 CH₂=CH-0 F H F F

1014 CN F F F F

1015 NCS F F F F

1016 F F F F F

1017 CI F F F F

1018 CF₃ F F F F

1019 OCF₃ F F F F

1020 CH₃ F F F F

1022 CH₂=CH F F F F

1023 CH₂=CH-0 F F F F

Examples 1024 to 1122

Analogously to Example 14 the following compounds are prepared:

No. R¹¹ _γιι _γ ⁱ² _γ ⁱ³ _γ ⁱ⁴ phases (T/°C)

14 CN H H H H K 182 I

1024 NCS H H H H 1025 F H H H H

1026 CI H H H H

1027 CF₃ H H H H

1028 OCF₃ H H H H

1029 CH₃ H H H H 1030 CH₃0 H H H H

1031 CH₂=CH H H H H

1032 CH₂=CH-0 H H H H

1033 CN F H H H

1034 NCS F H H H 1035 F F H H H

1036 CI F H H H

1037 CF₃ F H H H

1038 OCF₃ F H H H

1039 CH₃ F H H H 1040 CH₃0 F H H H

1041 CH₂=CH F H H H

1042 CH₂=CH-0 F H H H

1043 CN H H F H

1044 NCS H H F H 1045 F H H F H

1046 CI H H F H

1047 CF₃ H H F H

1049 CH₃ H H F H 1050 CH₃0 H H F H

1051 CH₂=CH H H F H

1052 CH₂=CH-0 H H F H

1053 CN F H F H

1054 NCS F H F H 1055 F F H F H

1056 CI F H F H

1057 CF₃ F H F H

1058 OCF₃ F H F H

1059 CH₃ F H F H

1060 CH₃0 F H F H

1061 CH₂=CH F H F H

1062 CH₂=CH-0 F H F H

1063 CN F F H H

1064 NCS F F H H

1065 F F F H H

1066 CI F F H H

1067 CFs F F H H

1068 OCF₃ F F H H

1069 CH₃ F F H H

1070 CH₃0 F F H H

1071 CH₂=CH F F H H

1072 CH₂=CH-0 F F H H

1073 CN H H F F

1074 NCS H H F F

1075 F H H F F

1076 CI H H F F

1077 CF₃ H H F F

1079 CH₃ H H F F

1080 CHsO H H F F

1081 CH₂=CH H H F F

1082 CH₂=CH-0 H H F F

1083 CN F F F H

1084 NCS F F F H

1085 F F F F H

1086 CI F F F H

1087 CF₃ F F F H

1088 OCF₃ F F F H

1089 CH₃ F F F H

1090 CH₃O F F F H

1091 CH₂=CH F F F H

1092 CH₂=CH-0 F F F H No. R 11 _γ ,1₁1_{1 \/}12_ _γ1₁3_J v _γ1W phases (T/°C)

1093 CN F H F F

1094 NCS F H F F

1095 F F H F F

1096 CI F H F F

1097 CFs F H F F

1098 OCF₃ F H F F

1099 CH₃ F H F F

1100 CH₃O F H F F

1101 CH₂=CH F H F F

1102 CH₂=CH-0 F H F F

1103 CN F F F F

1104 NCS F F F F

1105 F F F F F

1106 CI F F F F

1107 CF₃ F F F F

1109 CH₃ F F F F

1120 CH₃O F F F F

1121 CH₂=CH F F F F

1122 CH₂=CH-0 F F F F

Examples 1123 to 121C )

Analogously to Examples 15 and 16 the following compounds are prepared:

No. R 11 _γ ,1ⁿ1 ,12_- γⁱ _{a γ} 1₁4 phases (T/°C)

15 CN H H H H K 182 I

1123 NCS H H H H

1124 F H H H H

1125 CI H H H H

1126 CF₃ H H H H

1127 OCF₃ H H H H

1128 CH₃ H H H H

1129 CH₃0 H H H H

1130 CH₂=CH H H H H

1131 CH₂=CH-0 H H H H

1132 CN F H H H

1133 NCS F H H H

1134 F F H H H

1135 CI F H H H

1136 CF₃ F H H H

1137 OCF₃ F H H H

1138 CH₃ F H H H

1139 CH₃0 F H H H

1140 CH₂=CH F H H H

1141 CH₂=CH-0 F H H H

1142 CN H H F H

1143 NCS H H F H

16 F H H F H

1144 CI H H F H

1145 CF₃ H H F H

1146 OCF₃ H H F H

1147 CH₃ H H F H

1148 CH₃0 H H F H

1149 CH₂=CH H H F H

1150 CH₂=CH-0 H H F H

1151 CN F H F H

1152 NCS F H F H

1153 F F H F H

1154 CI F H F H

1155 CF₃ F H F H

1156 OCF₃ F H F H

1157 CH₃ F H F H

1158 CH₃O F H F H

1159 CH₂=CH F H F H

1160 CH₂=CH-0 F H F H

1161 CN F F H H

1162 NCS F F H H

1163 F F F H H

1164 CI F F H H

1165 CF₃ F F H H

1167 CHs F F H H

1168 CHsO F F H H

1169 CH₂=CH F F H H

1170 CH₂=CH-0 F F H H

1171 CN H H F F

1172 NCS H H F F

1173 F H H F F

1174 CI H H F F

1175 CF₃ H H F F

1176 OCF₃ H H F F

1177 CH₃ H H F F

1178 CH₃O H H F F

1179 CH₂=CH H H F F

1180 CH₂=CH-0 H H F F

1181 CN F F F H

1182 NCS F F F H

1183 F F F F H

1184 CI F F F H

1185 CF₃ F F F H

1187 CH₃ F F F H

1188 CH₃O F F F H

1189 CH₂=CH F F F H

1190 CH₂=CH-0 F F F H No. R¹¹ γ11 γ12 γ13 Y¹⁴ Phases (T/°C)

1191 CN F. H F F

1192 NCS F H F F

1193 F F H F F

1194 CI F H F F

1195 CFs F H F F

1196 OCF₃ F H F F

1197 CH₃ F H F F

1198 CH₃O F H F F

1199 CH₂=CH F H F F

1200 CH₂=CH-0 F H F F

1201 CN F F F F

1202 NCS F F F F

1203 F F F F F

1204 CI F F F F

1205 CFs F F F F

1206 OCF₃ F F F F

1207 CH₃ F F F F

1208 CH₃0 F F F F

1209 CH₂=CH F F F F

1210 CH₂=CH-0 F F F F

Examples 1211 to 129£ )

Analogously to Example 17 the following compounds are prepared:

No. R 11 _γιι _γ ⁱ² _γ ⁱ³ _γ ⁱ⁴ phases (T/°C)

17 CN H H H H K 111 I

1211 NCS H H H H

1212 F H H H H

1213 CI H H H H No. R 11 ,11 v_/12 _x,13 _\/14

Y" Y'* Y Y¹⁴ Phases (T/°C)

1214 CFs H H H H

1215 OCF₃ H H H H

1216 CH₃ H H H H

1217 CH₃0 H H H H

1218 CH₂=CH H H H H

1219 CH₂=CH-0 H H H H

1220 CN F H H H

1221 NCS F H H H

1222 F F H H H

1223 Ci F H H H

1224 CF₃ F H H H

1225 OCF₃ F H H H

1226 CHs F H H H

1227 CHsO F H H H

1228 CH₂=CH F H H H

1229 CH₂=CH-0 F H H H

1230 CN H H F H

1231 NCS H H F H

1232 F H H F H

1233 CI H H F H

1234 CFs H H F H

1235 OCF₃ H H F H

1236 CH₃ H H F H

1237 CHsO H H F H

1238 CH₂=CH H H F H

1239 CH₂=CH-0 H H F H

1240 CN F H F H

1241 NCS F H F H

1242 F F H F H

1243 CI F H F H

1244 CF₃ F H F H

1245 OCFs F H F H

1246 CHs F H F H

1247 CHsO F H F H

1248 CH₂=CH F H F H No. ,11 _γιι _γ ⁱ² _γ ⁱ³ _γ ⁱ⁴ phases (T/°C)

1249 CH₂=CH-0 F H F H

1250 CN F F H H

1251 NCS F F H H

1252 F F F H H

1253 CI F F H H

1254 CFs F F H H

1255 OCFs F F H H

1256 CHs F F H H

1257 CH₃0 F F H H

1258 CH₂=CH F F H H

1259 CH₂=CH-0 F F H H

1260 CN H H F F

1261 NCS H H F F

1262 F H H F F

1263 CI H H F F

1264 CF₃ H H F F

1265 OCF₃ H H F F

1266 CHs H H F F

1267 CHsO H H F F

1268 CH₂=CH H H F F

1269 CH₂=CH-0 H H F F

1270 CN F F F H

1271 NCS F F F H

1272 F F F F H

1273 CI F F F H

1274 CF₃ F F F H

1275 OCF₃ F F F H

1276 CH₃ F F F H

1277 CH₃O F F F H

1278 CH₂=CH F F F H

1279 CH₂=CH-0 F F F H

1280 CN F H F F

1281 NCS F H F F

1282 F F H F F

1283 CI F H F F No. R 11

Y ,1"1 Y1^,2 Y1^l3^ύ Y_/1¹4⁴ Phases (T/°C)

1284 CF₃ F H F F

1285 OCF₃ F H F F

1286 CH₃ F H F F

1287 CH₃0 F H F F

1288 CH₂=CH F H F F

1289 CH₂=CH-0 F H F F

1290 CN F F F F

1291 NCS F F F F

1292 F F F F F

1293 CI F F F F

1294 CF₃ F F F F

1295 OCF₃ F F F F

1296 CH₃ F F F F

1297 CH₃0 F F F F

1298 CH₂=CH F F F F

1299 CH₂=CH-0 F F F F

Exampl e 1300

Analogously to Example 1 the following compound is prepared

Example 1301

Analogously to Example 1 the following compound is prepared

Comparative Use-example

5% of the chiral agent R-5011 have been solved in the achiral liquid crystal mixture M-0 with the composition and properties given in table 1 below.

The resulting mixture CM was filled into an electro optical test cell with inter-digital electrodes on one substrate side. The electrode width was 10 μm, the distance between adjacent electrodes was 10 μm and the cell gap was also 10 μm. This test cell has been evaluated electro-optically between crossed polarisers.

At low temperatures, the filled cell showed the typical texture of a chiral nematic mixture, with an optical transmission between crossed polarisers without applied voltage. On heating, at a temperature of 36°C (Ti) the mixture was optically isotropic, being dark between the crossed polarisers. This indicated the transition from the chiral nematic phase to the blue phase at 36°C. Table 1 : Composition and Properties of Host Mixture M-0

Compound Concentration Physical Properties

Abbreviation / mass-%

GZU-3A-N 15.0 T(N, I) 56.5 °C

GZU-4A-N 15.0

GZU-40-N 15.0 Δn (20°C, 589 nm) = 0.164

UZU-3A-N 8.0

CUZU-2-N 9.0

CUZU-3-N 9.0

CUZU-4-N 9.0

HP-3N.F 6.0

HP-4N.F 6.0

HP-5N.F 8.0

Σ 100.0

Up to a temperature of 43°C (T₂) the cell showed a clear electro optical effect under applied voltage, for example at 38°C, applying a voltage of 46 V lead to a maximum of the optical transition. At a temperature of 43°C the voltage needed for a visible electro-optical effect started to increase strongly, indicating the transition from the blue phase to the isotropic phase at this temperature.

The temperature range (ΔT(BP)), where the mixture can be used electro- optically in the blue phase was identified as ranging from 36°C to 43°C, i.e. as being 7° wide (= T₂ - Ti = 43°C - 36°C). The results are listed in table 2 below. Table 2:

Use-example 1

In this use-example 10 % of the compound of example 1 and 5% of the chiral agent R-5011 have been solved in the achiral liquid crystal mixture M-0 with the composition and properties given in the following table.

The resulting mixture M-1 was filled into an electro optical test cell like that used in the comparative example and investigated as described there.

At low temperatures, the filled cell showed the typical texture of a chiral nematic mixture, with an optical transmission between crossed polarisers without applied voltage. On heating, at a temperature of 25.8°C the mixture was optically isotropic, being dark between the crossed polarisers. This indicated the transition from the chiral nematic phase to the blue phase at 25.8°C. Up to a temperature of 33°C, the cell showed a clear electro optical effect under applied voltage, for example at 25.°C application of a voltage of 43.2 volt lead to a maximum of the optical transition. At a temperature of 33°C the voltage needed for a visible electro-optical effect increased strongly, indicating the transition from the blue phase to the isotropic phase at 33°C without applied voltage. The temperature range (ΔT(BP)), where the mixture can be used electro- optically in the blue phase was identified as ranging from 25.8°C to 33°C, i.e. as being 7.2° wide (= T₂ - Ti = 33°C - 25.8°C. This is slightly larger than the respective range of 7 K, being found in the chiral reference mixture CM with only 5% of R-5011 added to mixture M-0 and at the same time the phase range of the blue phase is shifted significantly towards ambient temperature, which facilitates practical handling. And, at the same time, the operation voltage is reduced. The results are also shown in table 2.

Use-example 2

In this use-example 10 % of the compound of example 2 and 5% of the chiral agent R-5011 have been solved in the achiral liquid crystal mixture M-0 with the composition and properties given in the following table.

The resulting mixture M-1 was filled into an electro optical test cell like that used in the comparative example and investigated as described there.

At low temperatures, the filled cell showed the typical texture of a chiral nematic mixture, with an optical transmission between crossed polarisers without applied voltage. On heating, at a temperature of -1.2°C the mixture was optically isotropic, being dark between the crossed polarisers. This indicated the transition from the chiral nematic phase to the blue phase at -1.2°C. Up to a temperature of 12°C, the cell showed a clear electro optical effect under applied voltage, for example at 0.8°C, applying 43 volt lead to a maximum of the optical transition. At a temperature of 12°C the voltage needed for a visible electro-optical effect increased strongly, indicating the transition from the blue phase to the isotropic phase at 12°C without applied voltage.

The temperature range (ΔT(BP)), where the mixture can be used electro- optically in the blue phase was identified as ranging from -1.2°C to 12°C, i.e. as being 13.2° wide (= T₂ - Ti = 12°C - (-1.2°C)). This is significantly larger than the respective range of 7 K, being found in the chiral reference mixture CM with only 5% of R-5011 added to mixture M-0. The results are also shown in table 2.

Use-examples 3 to 5

Like in use-example 1, alternatively 10 % each of the respective compound of interest together with 5% of the chiral agent R-5011 have been solved in the achiral liquid crystal mixture M-0 of use example 1. In these use-examples alternatively the compounds of examples 3 to 5, respectively, have been used, as indicated in table 2.

The respective mixtures (M-3 to M-5) have been investigated as described under comparative-use-example and under use-example 1. The results are shown in table 2 for comparison. All of these examples showed significantly wider temperature ranges over which the electro-optical effect can be used in the blue phase compared to that of the reference mixture CM.

Use-examples 6.1 to 6.3

Like in use-example 1 , the compound of interest has been solved together with 5% of the chiral agent R-5011 solved in the achiral liquid crystal mixture M-0 of use example 1. In all of these three use-examples the compound of example 6 has been used, as indicated in table 3. The concentration of this compound has been varied from 10% over 7% to 4% in these three use-examples. The results are shown in table 3.

The respective mixtures (M-6.1 to M-6.3) have been investigated as described under comparative-use-example and under use-example 1. The results are shown in table 2 for comparison. All of these examples showed significantly wider temperature ranges over which the electro-optical effect can be used in the blue phase compared to that of the reference mixture CM. With a width of 12.7°, the widest range of the blue phase has been observed for mixture M-6.2 containing 7% of the compound of example 6. This mixture has also the same low operation voltage as the mixture M-6.3 with 4% of the compound of interest. Use-examples 7.1 to 7.4

Like in use-example 1 , the compound of interest has been solved together with 5% of the chiral agent R-5011 solved in the achiral liquid crystal mixture M-0 of use example 1. In all of these four use-examples the compound of example 7 has been used, as indicated in tables 3 and 4. The concentration of this compound has been varied from 10% over 7% o and 4% to 2% in these four use-examples. The results are shown in tables 3 and 4.

The respective mixtures (M-7.1 to M-7.4) have been investigated as described under comparative-use-example and under use-example 1. The5 results are shown in table 3 and 4. The mixtures M-7.2 to M-7.4 of the respective use examples showed significantly wider temperature ranges over which the electro-optical effect can be used in the blue phase compared to that of the reference, mixture CM. The widest range of the blue phase has been observed for mixture M-7.2 (which contains 7% of0 the compound of example 7) with a width of 17.5°. In this series of mixtures with successively decreasing concentration of the compound of example 7 the lowest operation voltage is observed for the mixture M-7.3 with 4% of the compound of interest, which still has a blue phase which is 11.1° wide. 5

Use-examples 8 to 12

Like in use-example 1 , the 10% each of the respective compounds of interest alternatively have been together with 5% of the chiral agent R-0 5011 solved in the achiral liquid crystal mixture M-0 of use example 1. The results are shown in tables 4 and 5.

The respective mixtures (M-8 to M-12) have been investigated as described under comparative-use-example and under use-example 1. The5 results are shown in tables 4 and 5. Use-examples 13.1. 13.2, 14.1 and 14.2

Like in use-example 1 , the compound of interest has been solved together with 5% of the chiral agent R-5011 in the achiral liquid crystal mixture M-0 of use example 1. In the first two of these four use-examples the compound of example 13 has been used, whereas in the second two the compound of example 14 has been used, as indicated in tables 5 and 6 The results are shown in tables 5 and 6. In mixtures M-13.1 and M-14.1 10% each of the compounds have been used, whereas in mixtures M-13.2 and M-14.2 the respective concentration is 5%.

The respective mixtures (M-13.1 to M-14.2) have been investigated as described under comparative-use-example and under use-example 1. The results are shown in table 5 and 6. Especially mixture M-13.2 has a wide temperature ranges of the blue phase of 14.2°. Mixture M-14.1 has a somewhat smaller range of the blue phase (with 12.5°) but it has a favourably low operation voltage.

Use-examples 15 and 16

Like in use-example 1 , the 10% of the respective compounds of interest, now of examples 15 and 16, respectively, have been alternatively solved been together with 5% of the chiral agent R-5011 in the achiral liquid crystal mixture M-0 of use example 1. The results are shown in table 6.

The respective mixtures (M-15 and M-16) have been investigated as described under comparative-use-example and under use-example 1. The results are shown in table 6.

Use-examples 17.1 to 17.3

Like in use-example 1 , the compound of interest has been solved together with 5% of the chiral agent R-5011 solved in the achiral liquid crystal mixture M-0 of use example 1. In all of these three use-examples the compound of example 17 has been used, as indicated in table 6 and 7. The concentration of this compound has been varied from 10% over 7% to 4% in these three use-examples. The results are shown in tables 6 and 7.

The respective mixtures (M-17.1 to M-17.3) have been investigated as described under comparative-use-example and under use-example 1. All of these examples showed significantly wider temperature ranges over which the electro-optical effect can be used in the blue phase compared to that of the reference mixture CM. With a width of 13.8°, the widest range of the blue phase has been observed for mixture M-17.2 containing 7% of the compound of example 17. This mixture has also a similarly low operation voltage as the mixture M-17.3 with 4% of the compound of interest.

Use-examples 18 to 23

Like in use-example 1, the 10% of the respective compounds of interest, now of examples 18 to 22 and 30, respectively, have been alternatively solved been together with 5% of the chiral agent R-5011 in the achiral liquid crystal mixture M-0 of use example 1. The results are shown in tables 7 and 8.

The respective mixtures (M-18 to M23) have been investigated as described under comparative-use-example and under use-example 1. The results are shown in tables 7 and 8.

Use-Example 24

5% of the compound of example 1300 are added together with 5% of the chiral dopant R-5011 to the host mixture of M-0 of use example 1 and investigated as described there. The results are shown in table 8 below. Table 3:

Table 5:

Table 7:

Table 8:

Claims

Claims

Mesogenic compound, characterized in that it comprises a mesogenic group and one or more bulky end groups, which each comprise at least two ring elements, where two of these ring elements are linked to a centre atom or to a centre group by a direct bond or via a linking group.

Compound according to claim 1 , characterized in that two of the ring elements in at least one of the one or more bulky end groups are linked to each other, either directly or via a linking group, which may be identical to or different from the linking group mentioned in claim 1.

Compound according to claim 1 , characterized in that it is a compound of formula I

wherein

MG is a divalent radical of the formula

BG represents either two monovalent radicals, short MR, each independently of one another, of formula MR-1 or a divalent radical, short DR, selected from the group of formulae DR-1 , DR-2 and DR-3,

DR-1 IS

DR-2 IS

R 11 is H, F, CI, Br, I, CN, N0₂, NCS, SF₅ , S0₂CF₃ or alkyl which is straight chain or branched, is unsubstituted, mono substituted or polysubstituted by F, CI, Br, I or CN, and in which one or more non-adjacent CH₂ groups are optionally replaced, in each case independently from one another, by -0-, -S-, -NH-, -NR⁰¹-, -SiR⁰¹R⁰²-, -CO-, -COO-, -OCO-, -OCO-0-, -S-CO-, -CO-S-, -CY¹=CY²- or -C≡C- in such a manner that O and/or S atoms are not linked directly to one another, or R¹¹ denotes PG-SG,

R 12 has one of the meanings given for R >11 and for MR or is

R¹³ to R¹⁵ have, independently of each other, one of the meanings given for R¹¹,

R⁰¹ and R⁰² are, independently of each other, H or alkyl with 1 to 12 C-atoms,

R is H or alkyl

PG is a polymerisable or reactive group,

SG is a spacer group or a single bond, and

C¹⁴

are, independently of each other, an aromatic or alicyclic ring, or a group comprising two or more fused aromatic and/or alicyclic rings, wherein these rings optionally contain one or more hetero atoms selected from N, O and/or S, and are optionally monosubstituted or polysubstituted by R,

Z° is C or N,

Z¹¹ to Z¹⁶ are, independently of each other, -0-, -S-, -CO-,

-CO-O-, -O-CO-, -S-CO-, -CO-S-, -0-CO-0-, -CO-NR⁰¹-, -NR⁰¹-CO-, -OCH2-, -CH2O-, -SCH2-, -CH₂S-, -CF2O-, -OCF2-, -CF₂S-, -SCF-, -CH₂CH₂-, -CF₂CH2-, -CH₂CF₂-, -CF₂CF-, -CH=N-, -N=CH-,

-N=N-, -CH=CR⁰¹-, -CY⁰¹=CY⁰²-, -C≡C-, -(CH₂) ₄-, -CH=CH-CO-0-, -0-CO-CH=CH- or a single bond,

Y⁰¹ and Y⁰² are, independently of each other, H, F, CI or CN,

X¹¹ to X¹⁵ have, independently of each other, one of the meanings given for Z¹¹ and X¹² alternatively may be -CG-Z¹¹- or -Z¹¹-CG-,

CG is

Y¹¹ has one of the meanings given for Z¹¹ or is or is

-(CH₂)₃- or -CH₂-CH(CH₃)-,

n is O or l ,

10 m is 1 in case "BG" is "MR" and 2 in case "BG" is

"DR",

o is 1 or 2,

15 n + o is 2,

p and q are, independently of each other, 0 or 1 ,

s, t and u are, independently of each other, 0, 1 or 2.

20

4. Compound according to at least one of claims 1 to 3, characterized in that it comprises a non-fused bulky end group.

5. Compound according to at least one of claims 1 to 4, characterized in

25 that it comprises a fused bulky end group.

6. Compound according to at least one of claims 1 to 5, characterized in that it comprises two bulky end groups.

Of] u 7. Medium, characterized in that it comprises a compound of formula I according to at least one of claims 1 to 6.

8. Medium according to claim 7, characterized in that it is a mesogenic medium.

35

9. Medium according to at least one of claims 7 and 8, characterized in that it is a light modulation medium.

10. Medium according to at least one of claims 7 to 9, characterized in that it has a blue phase.

11. Light modulation element, characterized in that it comprises a medium according to at least one of claims 7 to 10.

12. Use of a compound according to at least one of claims 1 to 6 in a mesogenic medium.

13. Use of a medium according to at least one of claims 7 to 10 in a light modulation element.

14. Electro-optical display, characterized in that it comprises a medium according to at least one of claims 7 to 10.