摘要:
The invention relates to thermochromic liquid crystalline phases with at least two components, characterized in that at least one component is an optically active compound of the formula I ##STR1## wherein R.sup.1 and R.sup.2 are each independently a chiral residue, importing to the phase a tight helical twist. ##STR2## denotes a 1,4-phenylene group optionally substituted by fluorine, X.sup.1 and X.sup.2 are each independently O or NH,n is 1, 2 or 3 andm is 0 or 1, which can be used in electro-optic devices, in temperature indicating devices or for color-changing cosmetics.
摘要:
Biphenyl egters of formula (I), ##STR1## wherein formula (II) represents formula (III) or formula (IV), R.sub.1 represents C.sub.3 -C.sub.12 alkyl, alkoxy, alkylcarbonyloxy, alkoxycarbonyl or alkoxycarbonyloxy, j is O or 1 R.sub.2 represents C.sub.3 -C.sub.12 alkyl or alkoxy, one of Q.sub.1 or Q.sub.2 is fluorine and the other is hydrogen, provided that when j is O and formula (II) is formula (III) and both R.sub.1 and R.sub.2 are n-alkyl, then the total number of carbon atoms in R.sub.1 and R.sub.2 is more than 12. These compounds may be used as constituents of liquid crystal mixtures which show a room temperature ferroelectric smectic phase, and a number of such mixtures are described.
摘要:
Optically active naphthalene compounds having the formula: ##STR1## in which X and Y are selected from combinations (a), (b) and (c): (a) X is C.sub.1-10 alkyl or alkoxy and Y is C.sub.4-16 optically active alkyl, (b) X is C.sub.1-10 alkyl or alkoxy and Y is ##STR2## where R.sup.2 is C.sub.4-16 optically active alkyl, (c) X is ##STR3## where R.sup.1 is C.sub.1-10 alkyl or alkoxy and Y is C.sub.4-16 optically active alkyl. Ferroelectric smectic liquid crystal materials being compositions containing these compounds are also described.
摘要:
Disubstituted ethanes having a formula ##STR1## wherein R is alkyl, X is selected from hydrogen, ##STR2## wherein each R.sub.1 is selected from H, alkyl, alkoxy, halo and cyano and each of Q.sub.1, Q.sub.2, Q.sub.3 and Q.sub.4 is independently selected from H and F are useful as components of liquid crystal materials for electro-optical displays and compounds useful in the production of such components.
摘要:
The invention relates to ferroelectric smectic liquid crystal mixtures and compounds. The invention also relates to electro-optical devices incorporating these mixtures.
摘要:
Biphenyl esters of formula (I), wherein formula (II) represents formula (III) or formula (IV), R.sub.1 represents C.sub.3 -C.sub.12 alkyl, alkoxy, alkylcarbonyloxy, alkoxycarbonyl or alkoxycarbonyloxy, j is 0 or 1, R.sub.2 represents C.sub.3 -C.sub.12 alkyl or alkoxy, one of Q.sub.1 or Q.sub.2 is fluorine and the other is hydrogen, provided that when j is 0 and formula (II) is formula (III) and both R.sub.1 and R.sub.2 are n-alkyl, then the total number of carbon atoms in R.sub.1 and R.sub.2 is more than 12. These compounds may be used as constituents of liquid crystal mixtures which show a room temperature ferroelectric smectic phase, and a number of such mixtures are described.
摘要:
Liquid crystal compositions comprising as a first part between 40 and 99% by weight in aggregate of one or more materials selected from one or more of the six compound classes (1) to (3'), wherein R is in every instance an alkyl chain containing between 2 and 18 carbon atoms and R' is in every instance an alkyl chain containing between 1 and 17 carbon atoms, wherein one or more non-adjacent CH.sub.2 -groups are replaced by oxygen atoms, and as a second part between 1 and 60% by weight of one or more materials of high birefringence and high positive dielectric anisotropy which raise the S.sub.A -N transition temperature, exhibit a smectic A phase of relatively low melting point and wide smectic range. Such compositions may be used in liquid crystal cells, not only in display or optical information processing applications, but also for instance in temperature sensing applications. The operation of such cells may involve laser addressing, thermal or electrical addressing. ##STR1##
摘要:
The invention relates to dihalogenobenzene derivatives of the formula IR.sup.1 --A.sup.1 --Z.sup.1 --A.sup.2 --(Z.sup.2 --A.sup.3).sub.n --R.sup.2wherein R.sup.1, R.sup.2, A.sup.1, A.sup.2, A.sup.3, Z.sup.1, Z.sup.2 and n are as defined in the specification.
摘要:
2,3-difluorohydroquinone compounds of the formula I ##STR1## in which R.sup.1 and R.sup.2, in each case independently of one another, are alkyl having 1 to 15 C atoms or alkenyl having 3 to 15 C atoms which are unsubstituted, monosubstituted by cyano or at least monosubstituted by fluorine or chlorine, it also being possible for one CH.sub.2 group in these radicals to be replaced by --O--, --CO--, --CO--O--, --O--CO-- or --O--CO--O--,A.sup.1, A.sup.2 and A.sup.3, in each case independently of one another, are(a) trans-1,4-cyclohexylene, in which, in addition, one or two non-adjacent CH.sub.2 groups may be replaced by --O-- and/or --S--,(b) 1,4-phenylene, in which, in addition, one or two CH groups may be replaced by N, or(c) a radical from the group comprising piperidine-1,4-diyl, 1,4-bicylo (2,2,2)-octylene (sic), 1,3,4-thiadiazole-2,5-diyl, napththalene-2,6-diyl, decahydronaphthalene-2,6-diyl and 1,2,3,4-tetrahydronaphthalene-2,6-diyl, it being possible for the radicals (a) and (b) to be monosubstituted or polysubstituted by F, Cl, CH.sub.3 or CN,Z.sup.1 is --CO--O--, --O--CO--, --CH.sub.2 CH.sub.2 --, --OCH.sub.2 --, --CH.sub.2 O--, --C.tbd.C-- or a single bond,Q.sup.1 and Q.sup.2, in each case independently of one another, are --CO-- or --CH.sub.2 --,m and n are each 0, 1 or 2, and(m+n) is 0, 1 or 2,are suitable as components of liquid-crystalline phases.
摘要:
Disclosed are compounds of formula I ##STR1## wherein R is C.sub.1-12 -alkyl or halogenoalkyl wherein one or two non-adjacent CH.sub.2 groups are optionally replaced by --O--,A is ##STR2## Q is a bivalent radical of formula (2), and L.sup.0, L.sup.1 and L.sup.2 are each independently H or F, with the proviso that at least one of L.sup.0, L.sup.1 and L.sup.2 present in the molecule denotes F.