Hoffmann-la Roche Inc.

Other

Martin Petrzilka

Martin Schadt

Alois Villiger

Arthur Boller

Inge Pracht

Georges Hirth

Alfred Germann

Kuno Schleich

Georg Trickes

Urs Ruf

Gottfried Oesterhelt

Compounds of the formula ##STR1## wherein n stands for the number 0 or 1; the rings A.sup.1, A.sup.2 and A.sup.3 represent 1,4-phenylene, 2-fluoro-1,4-phenylene or trans-1,4-cyclohexylene or one of these rings also represents a 2,5-disubstituted pyrimidine ring or a trans-2,5-disubstituted m-dioxane ring; X.sup.1 represents a single covalent bond, --COO--, --OOC--, --CH.sub.2 CH.sub.2 --, p--C.sub.6 H.sub.4 --, --CH.sub.2 CH.sub.2 --p-- C.sub.6 H.sub.4 --, --CH.sub.2 CH.sub.2 --p--C.sub.6 H.sub.4 --CH.sub.2 CH.sub.2 -- or, insofar as the rings A.sup.1 and A.sup.2 represent 1,4-phenylene, also --NON--; R.sup.2 represents 1E-alkenyl, 2Z-alkenyl, 3E-alkenyl, 4-alkenyl or alkenyloxy, with the proviso that the oxygen atom in alkenyloxy is linked with a saturated carbon atom; and R.sup.1 signifies 1E-alkenyl, 2Z-alkenyl, 3E-alkenyl, 4-alkenyl or, insofar as R.sup.2 represents alkenyloxy, also alkyl, their manufacture, as well as liquid crystalline mixtures and the use for electro-optical purposes.

Liquid crystals

Compounds of the formula ##STR1## wherein, inter alia, R.sup.1 is hydrogen or straight-chain alkyl; R.sup.2 is --CN, --R, --COR, --COOR; R is alkyl; A is a group with 1 to 4 six-membered rings, these rings being linked directly with one another and with ring B in each case via a single covalent bond or being linked at one or two positions also via ester or ether groups; the six-membered rings in A and ring B each are 1,4-phenylene or trans-1,4-cyclohexylene or one of these rings also is trans-2,5-disubstituted m-dioxane; m can be 0 when ring B is trans-1,4-cyclohexylene or trans-2,5-disubstituted m-dioxane, liquid crystalline mixtures which contain these compounds as well as their use for electro-optical purposes are described.

This invention concerns compounds of the formula: ##STR1## wherein X is a single covalent bond, --CH.sub.2 CH.sub.2 --, 1,4-phenylene, a 2,5-disubstituted pyrimidine ring or a group of the formula: ##STR2## ring A is trans-1,4-cyclohexylene or, when X is a single covalent bond, ring A may also be 1,4-phenylene, a 2,5-disubstituted pyrimidine ring or a trans-2,5-disubstituted m-dioxane ring; and

Liquid crystalline compounds and mixtures

There is described a liquid crystalline mixture for electro-optical devices which are operated according to the two-frequency matrix addressing procedure. The mixture consists of three components A, B and C, each of which contains one or more compounds. Component A has a viscosity of at most about 40 cp, a clearing point of at least about 40.degree. C. and a dielectric anisotropy between about -2 and about +1. Component B has a dielectric anisotropy below about -2 both above and below the cross-over frequency of the total mixture and component C has a dielectric anisotropy above about +10, a clearing point of at least about 100.degree. C. and there is a cross-over frequency in the total mixture of at most about 15 kHz at 20.degree. C. Novel compounds for such mixtures and their manufacture and use are also described. The novel mixtures make possible especially high multiplex rates and short response times.

Liquid crystal mixture

Compounds of the formula ##STR1## wherein X.sup.2 is a single covalent bond or --COO--; X.sup.1 is a single covalent bond, --COO--, --CH.sub.2 CH.sub.2 -- or when X.sup.2 is --COO--, X.sup.1 also can be p--C.sub.6 H.sub.4 --, p--C.sub.6 H.sub.4 --CH.sub.2 CH.sub.2 --, --CH.sub.2 CH.sub.2 --p--C.sub.6 H.sub.4, p--C.sub.6 H.sub.4 --COO-- or --COO--p--C.sub.6 H.sub.4 ; ring A is a benzene ring or trans-1,4-cyclohexylene; ring B is a benzene ring or when X.sup.2 is --COO-- and X.sup.1 is a single covalent bond, --COO-- or --CH.sub.2 CH.sub.2 --, ring B also can be trans-1,4-cyclohexylene; Z.sup.1, Z.sup.2 and Z.sup.3 individually are hydrogen or when positioned on a benzene ring which is not linked directly with a further ring via a single covalent bond, Z.sup.1, Z.sup.2 and Z.sup.3 also can be halogen, cyano or methyl; Y.sup.2 is cyano, nitro, 2,2-dicyanovinyl or when Y.sup.1 is hydrogen Y.sup.2 also can be 2,2-dicyano-1-methylvinyl; Y.sup.1 is halogen, cyano, C.sub.1 -C.sub.3 -alkyl or, when X.sup.1 includes a benzene ring of --COO-- or Y.sup.2 is nitro or at least one of Z.sup.1 and Z.sup.2 is other than hydrogen, Y.sup.1 also can be hydrogen; and R.sup.1 is C.sub.1 -C.sub.12 -alkyl or when positioned on a benzene ring R.sup.1 also can be C.sub.1 -C.sub.12 -alkoxy, their manufacture and use in liquid crystalline mixtures are described.

Esters

Liquid crystalline mixtures containing compounds of the formula ##STR1## wherein n stands for the number 0 or 1; X.sup.1 and X.sup.2 denote single covalent bonds or one of the symbols X.sup.1 and X.sup.2 also denotes --COO--, --OOC-- or --CH.sub.2 CH.sub.2 --; the rings A.sup.1, A.sup.2 and A.sup.3 represent 1,4-phenylene, 2-fluoro-1,4-phenylene or trans-1,4-cyclohexylene or one of these rings also represents a 2,5-disubstituted pyrimidine ring or a trans-2,5-disubstituted m-dioxane ring; R.sup.1 signifies 4-alkenyl or on a cyclohexyl ring also 2Z-alkenyl; and R.sup.2 denotes alkyl, alkoxy, --CN or --NCS, as well as the manufacture of these compounds and the use for electro-optical purposes are described.

Novel liquid crystal mixtures

Compounds of the formula: ##STR1## wherein R.sup.1 and R.sup.2 are independently straight-chain C.sub.1 -C.sub.12 -alkyl or when positioned on an aromatic ring R.sup.1 and R.sup.2 may also independently be straight-chain C.sub.1 -C.sub.12 -alkoxy, or one of R.sup.1 and R.sup.2 may also be a group of the formula: ##STR2## X.sup.1 and X.sup.2 are independently single covalent bonds or one of X.sup.1 and X.sup.2 may also be --CH.sub.2 CH.sub.2 --; rings A.sup.1 and A.sup.2 are independently 1,4-phenylene or, when X.sup.1 or X.sup.2 is --CH.sub.2 CH.sub.2 --, rings A.sup.1 and A.sup.2 may also independently be trans-1,4-cyclohexylene; and R.sup.3 is straight-chain C.sub.1 -C.sub.12 -alkyl or when positioned on an aromatic ring R.sup.3 may also be straight-chain C.sub.1 -C.sub.12 -alkoxy. Their manufacture and use in liquid crystalline mixtures are described.

Dicyano compounds

Compounds of the formula ##STR1## wherein R.sup.1 is hydrogen or straight-chain alkyl; R.sup.2 is --CN, --R, --COR, --COOR or when R.sup.2 is positioned on an aromatic ring R.sup.2 also can be --OR, --OOCR or --F; R is alkyl; A is a group with 1 to 4 six-membered rings, these rings being linked directly with one another and with ring B in each case via a single covalent bond or being linked at one or two positions also via --COO--, --OOC-- or --CH.sub.2 CH.sub.2 --; the six-membered rings in A and ring B each are 1,4-phenylene or trans-1,4-cyclohexylene or one of these rings also is trans-2,5-disubstituted m-dioxane, 2,5-disubstituted pyrimidine or 3,6-disubstituted pyridazine, with the proviso that a maximum of two adjacent trans-1,4-cyclohexylene rings are linked directly via a single covalent bond; and m is the integer 2, or when ring B is trans-1,4-cyclohexylene or trans-2,5-disubstituted m-dioxane, m also can be the integer 0, their manufacture, liquid crystalline mixtures which contain these compounds as well as the use of these compounds for electro-optical purposes are described. Additionally, compounds of the formula ##STR2## wherein R.sup.8 is straight-chain C.sub.1 -C.sub.12 alkyl, their manufacture, liquid crystalline mixtures which contain these compounds and their use for electro-optical purposes are described.

This invention concerns compounds of the formula: ##STR1## wherein n is 1 and X is --COO--, --OOC-- or --CH.sub.2 CH.sub.2 --; or n is O and X is --CH.sub.2 CH.sub.2 --;

Compounds of the formula: ##STR1## wherein one of X.sup.1 and X.sup.2 is --CH.sub.2 CH.sub.2 -- and the other is --CH.sub.2 CH.sub.2 -- or a single covalent bond,

Benzonitriles

Cyclohexanecarbonitriles

Liquid crystalline mixtures containing compounds of the formula ##STR1## wherein n stands for the number 0 or 1; X.sup.1 and X.sup.2 denote single covalent bonds or one of the symbols X.sup.1 and X.sup.2 also denotes --COO--, --OOC-- or --CH.sub.2 CH.sub.2 --; the rings A.sup.1, A.sup.2, and A.sup.3 represent 1,4-phenylene, 2-fluoro-1,4-phenylene or trans-1,4-cyclohexylene or one of these rings also represents a 2,5-disubstituted pyrimidine ring or a trans-2,5-disubstituted m-dioxane ring; R.sup.1 signifies 4-alkenyl or on a cyclohexyl ring also 2Z-alkenyl; and R.sup.2 denotes alkyl, alkoxy, --CN or --NCS, as well as the manufacture of these compounds and the use for electro-optical purposes are described.

Coloring substance-containing liquid crystal mixtures

Compounds of the formula ##STR1## wherein B is --C.tbd.C-- or --CH.sub.2 CH.sub.2 --, R.sup.1 is straight-chain C.sub.1 -C.sub.12 -alkyl and R.sup.2 is straight-chain C.sub.1 -C.sub.12 -alkyl or straight-chain C.sub.1 -C.sub.12 -alkoxy, their manufacture and use in liquid crystalline mixtures are described.

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Kaiseraugst, Switzerland

Martin Petrzilka