摘要:
Optically active compounds of formula (I), where X has a structure (II) and B is C.sub.1-12 alkyl, a chiral group or a group having a general structure (III), where R and R' are H, C.sub.1-12 alkyl, alkoxy, alkylcarbonyloxy, or alkoxycarbonyl, each ring (IV) and (V) is the same or different, A and D are single bonds or bridging groups, each a and d is 0 or 1; Z, Z' are CN, Cl, F, Br or CF.sub.3 ; provided when Z is CN or Cl, then when B is alkyl X-Y is not (VI) or (VII). Ferroelectric smectic liquid crystal mixtures containing these compounds are also described. ##STR1##
摘要:
Liquid crystal compounds of formula (I) are described, where formula (I) is given as R.sub.1 --A--(X.sub.m --(B).sub.n --R.sub.2 where A is selected from nathyl, flourinated naphthyl, brominated naphthyl, B is selected from phenyl, methylated phenyl, brominated phenyl, fluorinated phenyl, thiophene, pyrimidine and pyridine, R.sub.1 and R.sub.2 are independently selected from alkyl, alkoxy, alkynyl, thioalkyl, Br, CN, SCN, NCS, perfluoroalkyl, perfluoroalkoxy and hydrogen, X is selected from C.tbd.C, COO and C.tbd.C, m is 0 or 1, n is 0 or 1 where m is 1 and n is 0 where m is 0; provided that where A is naphthyl, n is 1 and m is 0 then B is selected from methylated phenyl, brominated phenyl, thiophene, pyrimidine and pyridine; and further provided that where A is naphthyl, X is C.tbd.C, m is 1 and n is 1, then B is selected from thiophene, pyrimidine and pyridine. Also described are liquid crystal compounds suitable for inclusion in devices utilizing pretransitional characteristics of liquid crystalline materials in the isotropic phase and described by formula (II): R.sub.3 --J--(Y).sub.p --(Z).sub.q --R.sub. 4, where J is selected from nathyl, fluorinated naphthyl, brominated naphthyl, Z is selected from phenyl, methylated phenyl, brominated phenyl, fluorinated phenyl, thiophene, pyrimidine and pyridine, R.sub.1 and R.sub.2 are independently selected from alkyl, alkoxy, alkynyl, thioalkyl, Br, CN, SCN, NCS, perfluoroalkyl, perfluoroalkoxy and hydrogen, Y is selected from C.dbd.C, COO and C.dbd.C, p is 0 or 1, q is 0 or 1 where p is 1 and q is 0 where p is 0.
摘要翻译:描述了式(I)的液晶化合物,其中式(I)为R1-A-(Xm-(B)n-R2,其中A选自萘基,氟化萘基,溴化萘基,B选自苯基 ,甲基化苯基,溴化苯基,氟化苯基,噻吩,嘧啶和吡啶,R1和R2独立地选自烷基,烷氧基,炔基,硫代烷基,Br,CN,SCN,NCS,全氟烷基,全氟烷氧基和氢,X选自C 3,C,COO和C 3 B C,m为0或1,n为0或1,其中m为1,n为0,其中m为0;条件是其中A为萘基,n为1,m为0,B为 选自甲基化苯基,溴化苯基,噻吩,嘧啶和吡啶;并且进一步规定,其中A为萘基,X为C 3 C 10,m为1,n为1,则B为噻吩,嘧啶和吡啶。 是适于包含在利用液晶材料的预过滤特性的器件中的液晶化合物 各向同性相并由式(II)描述:R3-J-(Y)对(Z)qR 4,其中J选自萘基,氟化萘基,溴化萘基,Z选自苯基,甲基化苯基,溴化苯基 ,氟化苯基,噻吩,嘧啶和吡啶,R1和R2独立地选自烷基,烷氧基,炔基,硫代烷基,Br,CN,SCN,NCS,全氟烷基,全氟烷氧基和氢,Y选自C = C,COO和C = C,p为0或1,q为0或1,其中p为1,q为0,其中p为0。
摘要:
A liquid crystal material which comprises a mixture of compounds includes at least one low viscosity additive compound of Formula (I) as follows:A--CH.sub.2.CH.sub.2 --B Formula (I)wherein A is selected from: ##STR1## and B is selected from: ##STR2##where R.sub.1 is selected from alkyl, alkoxy, alkylcarbonyloxy and alkoxycarbonyloxy; and R.sub.2 is alkyl; and where ##STR3## is a benzene ring; ##STR4## is a cyclohexane ring, which is in the trans-configuration if di-substituted; and ##STR5## is a bicyclo(2,2,2)octane ring.
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:
A method, device, and material for providing a fast switching liquid crystal display employs the ferro electric effect of chiral smectic liquid crystal material. To provide a uniform appearance the liquid crystal material is arranged to have a long cholesteric pitch at a temperature close to a smectic/cholesteric phase transistion temperature. This long cholesteric pitch allows liquid crystal molecules to cool from the cholesteric to smectic phase with a uniform alignment. The smectic material is contained in a cell between wells (2, 3) bearing electrodes (5, 6) and surface treated to provide homogeneous alignment of liquid crystal material (7).
摘要:
A method, device, and material for providing a fast switching liquid crystal display employs the ferro electric effect of chiral smectic liquid crystal material. To provide a uniform appearance the liquid crystal material is arranged to have a long cholesteric pitch at a temperature close to a smectic/cholesteric phase transistion temperature. This long cholesteric pitch allows liquid crystal molecules to cool from the cholesteric to smectic phase with a uniform alignment. The smectic material is contained in a cell between walls (2, 3) bearing electrodes (5, 6) and surface treated to provide homogeneous alignment of liquid crystal material (7).
摘要:
A liquid crystal display is arranged to provide very low minimum light trmission in one of its two switchable states. This makes it useful for a shutter (FIG. 1) and for high contrast digital displays (FIG. 2). A layer of a chiral smectic liquid crystal material is contained between two cell walls carrying electrode structures. The liquid crystal material has the following phases with temperature: isotropic.revreaction.cholesteric.revreaction.chiral smectic.revreaction.solid. The cholesteric pitch is large. The cell walls are surface treated to provide a parallel alignment of liquid crystal molecules. Crossed polarizers are arranged either side of the cell walls, one aligned with its optical axis parallel to the surface alignment of the adjacent cell wall. The device is switched by means of .+-.-d.c. voltage pulses and utilizes the ferro electric effect.
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:
An integrated electro-optical device according to the invention comprises a pixellated liquid crystal modulation layer superimposed over an electronic detection layer. Modulator pads for the liquid crystal layer may be formed as electrically conductive combs to achieve optical polarization. Where the liquid crystal layer provides selective absorption of unpolarized light, and separate polarizers between the liquid crystal and detection layers are therefore unnecessary, the device comprises such a liquid crystal layer superimposed over the electronic detector layer. Further, an integrated electro-optical device, optionally of the above type, has a plurality of pixels of the liquid crystal layer for each pixel of the detector array. This allows optical shuttering of the detector pixels by electrically modulating the pixellated liquid crystal layer.