The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 13, 1994
Filed:
Dec. 13, 1993
Stephen Kelly, Mohlin, CH;
Frans Leenhouts, Achel, BE;
Hoffmann-La Roche Inc., Nutley, NJ (US);
Abstract
Compounds of the formula ##STR1## wherein n stands for the number 0 or 1; R.sup.1 denotes a group R.sup.3 or R.sup.3 --A.sup.3 --Z.sup.2 -- and R.sup.2 denotes a group R.sup.4 or R.sup.4 --A.sup.4 --Z.sup.3 --; ring A.sup.1 is unsubstituted or halogen-, cyano- and/or methylsubstituted 1,4-phenylene in which optionally 1 CH group or 2 CH groups is/are replaced by nitrogen; A.sup.3 A.sup.4 and ring A.sup.2 each independently represent unsubstituted or halogen-, cyano- and/or methyl- -substituted 1,4-phenylene in which optionally 1 CH group or 2 CH groups is/are replaced by nitrogen or trans-1,4-cyclohexylene, trans-1,3-dioxane-2,5-diyl, 1-cyano-trans-1,4-cyclohexylene, bicyclo[2.2.2]octane- -1,4-diyl, naphthalene-2,6-diyl, tetralin-2,6-diyl or trans-decalin-2,6- diyl; Z.sup.1, Z.sup.2 and Z.sup.3 each independently are a single covalent bond, --COO--, --OOC--, --CH.sub.2 O--, --OCH.sub.2 --, --CH.sub.2 CH.sub.2 --, --C.vertline.C--, --(CH.sub.2).sub.3 O--, --O(CH.sub.2).sub.3 --, --(CH.sub.2).sub.4 -- or the trans form of --CH.dbd.CH-- CH.sub.2 O-- or --OCH.sub.2 --CH.dbd.CH--; R.sup.3 and R.sup.4 each independently denote halogen, cyano, --NCS, --CF.sub.3, --OCF.sub.3 or alkyl in which optionally one >CH--CH< is replaced by >C.dbd.C< and/or optionally one methylene group or two non- adjacent methylene groups is/are replaced by --O--, --COO-- and/or --OOC-- and/or optionally one methylene group is replaced by --CHX--; and X is halogen, cyano or methyl, as well as liquid crystalline mixtures which contain such compounds and their use for electro-optical purposes.