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US 4,395,350 AGranted
Liquid crystal mixtures
AssigneeHoffmann-La Roche Inc.
InventorsArthur Boller, Alfred Germann, Martin Schadt, Alois Villiger
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AssigneeHoffmann-La Roche Inc.
InventorsArthur Boller, Alfred Germann, Martin Schadt, Alois Villiger
Estimating the term…
Liquid crystal mixtures containing a coloring substance which comprise about 5 to about 40 weight % of trans-p-[5-(4-alkylcyclohexyl)-2-pyrimidinyl]benzonitriles, about 10 to about 60 weight % of trans-4-alkylcyclohexane carboxylic acid phenyl esters and about 0.1 to about 15 weight % of one or more coloring substances of the formula ##STR1## wherein m stands for the number 1 and X is alkoxy and Y is nitro; or m stands for the number 1 or 2; and X is p-alkoxyphenyl and Y is nitro or dialkylamino, or X is alkoxy and Y is -p-nitrophenyl or -(dialkylamino)phenyl; or m stands for the number 2, and X is alkoxy and Y is alkoxy, nitro or dialkylamino, or both X and Y are dialkylamino; and wherein the alkoxy denotes a straight-chain group containing 1 to 12 carbon atoms and the alkyl groups in the dialkylamino each denote a straight-chain alkyl group containing 1 to 4 carbon atoms are described.
A coloring substance-containing liquid crystal mixture which comprises about 5 to about 40 weight % of one or more trans-p-[5-(4-alkylcyclohexyl)-2-pyrimidinyl]benzonitriles of the formula ##STR18## wherein R.sup.1 is a straight-chain alkyl group containing 2 to 7 carbon atoms,
A coloring substance-containing liquid crystal mixture comprising trans-p-[5-(4-ethylcyclohexyl)-2-pyrimidinyl]benzonitrile, trans-p-[5-(4-pentylcyclohexyl)-2-pyrimidinyl]benzonitrile, trans-p-[5-(4-heptylcyclohexyl)-2-pyrimidinyl]benzonitrile, trans-4-propylcyclohexane carboxylic acid p-cyanophenyl ester, trans-4-pentylcyclohexane carboxylic acid p-cyanophenyl ester, trans-4-butylcyclohexane carboxylic acid p-(ethoxy)phenyl ester, trans-4-pentylcyclohexane carboxylic acid p-(methoxy)-phenyl ester, 4'-pentyl-4-cyanobiphenyl, one or more coloring substances selected from the group consisting of compounds of the formulas ##STR32## wherein R.sup.4 is a straight-chain alkyl group containing 1 to 9 carbon atoms, ##STR33## wherein R.sup.5 is a straight-chain alkyl group containing 1 to 9 carbon atoms, and ##STR34## wherein R.sup.7 is a straight-chain alkyl group containing 5 to 8 carbon atoms,
A coloring substance-containing liquid crystal mixture, in accordance with claim 25, which contains about 7.73 parts by weight of trans-p-[5-(4-ethylcyclohexyl)-2-pyrimidinyl]benzonitrile, about 5.52 parts by weight of trans-p-[5-(4-pentylcyclohexyl)-2-pyrimidinyl]benzonitrile, about 14.38 parts by weight of trans-p-[5-(4-heptylcyclohexyl)-2-pyrimidinyl]benzonitrile, about 7.64 parts by weight of trans-4-propylcyclohexane carboxylic acid p-cyanophenyl ester, about 6.95 parts by weight of trans-4-pentylcyclohexane carboxylic acid p-cyanophenyl ester, about 14.13 parts by weight of trans-4-butylcyclohexane carboxylic acid p-(ethoxy)-phenyl ester, about 12.62 parts by weight of trans-4-pentylcyclohexane carboxylic p-(methoxy)phenyl ester, about 27.28 parts by weight of 4'-pentyl-4-cyanobiphenyl, about 0.95 parts by weight of the compound of formula III wherein R.sup.4 is heptyl, about 1 part by weight of the compound of formula IV wherein R.sup.5 is methyl or heptyl, about 1.80 parts by weight of the compound of formula VI wherein R.sup.7 is heptyl and up to about 4 parts by weight of a compound selected from the group consisting of optically active 4'-(2-methylbutyl)-4-cyanobiphenyl and optically active 4'-(2-methylbutyloxy)-4-cyanobiphenyl.
Dependencies are inferred from the claim text.