摘要:
Optically active 1,3-dioxolane derivatives which carry a mesogenic radical in the 4-position and have the general formula (I) ##STR1## are suitable for use as doping agents in liquid-crystal mixtures--in particular ferroelectric liquid-crystal mixtures. The symbols in the general formula have the following meanings:R.sup.1 is composed analogously to the part of the general formula on the right-hand side of X or is an alkyl or alkylene radical which can be substituted,R.sup.2, R.sub.3 and R.sup.4 are H or alkyl (R.sup.4 is also alkenyl) which can also be substituted [R.sup.2 and R.sup.3, together with the C(2) of the dioxolane ring are also a cycloaliphatic radical or a keto group], J, l and n are zero, 1 or 2 and k and m are zero or 1, subject to the proviso that, if k is zero n is zero and if n is zero m is zero and 1.ltoreq.J+l+n.ltoreq.3,--A.sup.1, --A.sup.2 and --A.sup.3 are an aromatic, heterocyclic or aliphatic ring system, --M.sup.1 and --M.sup.2 are --CO--O, --0--CO, --CH.sub.2 CH.sub.2, --CH.dbd.CH, --CH.sub.2 O, --OCH.sub.2 or --C.tbd.C andX is O, S or O--CO--O.
摘要:
Optically active oxirane-2-carboxylic acid esters with a mesogenic molecular component suitable as dopants in liquid-crystal mixtures. They result in liquid-crystalline ferroelectric phases with short switching times and in electroclinic phases with large electroclinic coefficients. A further advantage lies in the fact that they induce a helix with a very small pitch so that they are also suitable for helix compensation in LC mixtures.
摘要:
Chiral oxazolidinones of the formula (I) or (II) ##STR1## in which R.sup.1 is, for example, a straight-chain or branched alkyl radical having 1 to 16 carbon atoms orR.sup.2 and R.sup.3 are, for example, --H, --CH.sub.3 or phenyl,j, 1 and n are zero, 1 or 2,k and m are zero or 1,A.sup.1, A.sup.2 and A.sup.3 are, for example, phenyl or cyclohexyl,M.sup.1 and M.sup.2 are, for example, COO or CH.sub.2 O, andX is, for example, CH.sub.2 or COO,are suitable as dopes in liquid-crystal mixtures. They result in liquid-crystalline ferroelectric phases having short response times. A further advantage is that the oxazolidinones induce a helix of very low pitch, so that they are also suitable for helix compensation in LC mixtures.
摘要:
Azetidinones of the formula I ##STR1## in which, for example, R.sup.1 is an alkyl or alkenyl radical, R.sup.2 and R.sup.3 are hydrogen or an alkyl or alkenyl radical, Z is hydrogen or (pseudo)halogen, A.sup.1, A.sup.2 and A.sup.3 are a ring system, and M is a spacer group, can be added to liquid-crystal mixtures. Even when admixed in small amounts, they cause considerable twist in the cholesteric and smectic C* phase, which can compensate the pitch of another dope or produce a short S.sub.C * pitch.
摘要:
A ferroelectric, liquid-crystalline polymer is composed of repeating units of the formula I ##STR1## in which Y=H or CH.sub.3a=an integer from 6 to 12M=a group selected from the formulae which follow: ##STR2## in which --R.sup.2 =--CH.sub.3 or --Cl and b=an integer from 1 to 10. The abovementioned polymer has remarkably short response times. The polymer forms, alone or mixed with other LC components, an orthogonal smectic phase. It is possible to use this phase in the electroclinic mode.
摘要:
Ferroelectric, liquid-crystaline polymers contain repeating units of the formula (I) ##STR1## in which the symbols have the following meanings: B=a group having at least one chiral center, of the formula ##STR2## in which R.sup.6, R.sup.7 and R.sup.8 are identical or different and are H, CH.sub.3, OCH.sub.3, F, Cl or Br, and at least one of the groups R.sup.6, R.sup.7 and R.sup.8 must be H and X=H, F, Cl or Br and R.sup.9 =H or C.sub.1 -C.sub.10 -alkyl,Y=H, CH.sub.3 or F,R.sup.1 =for example a straight-chain or branched alkyl having 1 to 16 carbon atomsa=2 to 20, preferably 6 to 12b, c, d, e and f=0 or 1 with the proviso that d+e+f=2 or 3A.sup.1, A.sup.2, A.sup.3 =for example, 1,4-phenylene or 2,5-pyridinediyl,M.sup.1, M.sup.2 and M.sup.3 =for example CO--O, or O--CO, andG=for example, a straight-chain or branched alkylene having 1 to 16 carbon atoms.
摘要:
Optically active oxirane derivatives containing a mesogenic molecular unit are suitable as dopes in liquid-crystal mixtures. They give liquid-crystalline ferroelectric phases having short response times and electroclinic phases having large electroclinic coefficients. A further advantage is that they induce a helix of very small pitch, so that they are also suitable for helix compensation in LC mixtures.
摘要:
A ferroelectric, liquid-crystalline polymer is composed of repeating units of the formula (I) ##STR1## in which Y.sup.1 =H, CH.sub.3 or FY.sup.2 =H or FR.sup.1 = ##STR2## or an achiral alkyl having 2 to 16 carbon atoms, and R.sup.3 =H or CH.sub.3R.sup.2 =CH.sub.3, Cl or CNg and h=an integer from 0 to 10a=2 to 20, preferably 6 to 12b,c,d,e and f=0 or 1, where d+e+f=2 or 3A.sup.1,A.sup.2 and A.sup.3 =for example, 1,4-phenylene in which one or two hydrogen atoms may be substituted by F, Cl and/or CN, 1,4-cyclohexylene andM.sup.1,M.sup.2 and M.sup.3 =for example, CO--O or O--CO.These liquid-crystalline polymers have short response times and high resistance to mechanical stresses. They can be prepared by free-radical polymerization.
摘要翻译:PCT No.PCT / EP89 / 00745 Sec。 371日期1991年1月3日 102(e)日期1991年1月3日PCT Filed 1989年6月29日PCT公布。 出版物WO90 / 00584 日本1990年1月25日。铁电液晶聚合物由式(I)的重复单元(*化学结构*)组成,其中Y 1 = H,CH 3或F Y 2 = H或F R 1 =(* CHEMICAL 结构*)或具有2至16个碳原子的非手性烷基,并且R 3 = H或CH 3 R 2 = CH 3,Cl或CN g,h = 0至10的整数a = 2至20,优选6至12b,c ,d,e和f = 0或1,其中d + e + f = 2或3,A1,A2和A3 =例如,其中一个或两个氢原子可以被F,Cl和/ 或CN,1,4-亚环己基和M1,M2和M3 =例如CO-O或O-CO。 这些液晶聚合物具有较短的响应时间和高的机械应力抵抗力。 它们可以通过自由基聚合制备。
摘要:
New anthraquinone dyestuffs of the general formula I ##STR1## wherein Hal is a halogen atom and the two radicals R are each H or NH.sub.2 and the alkyl group has 1-8 C atoms, exhibit a high order parameter and are suitable for use as components of liquid-crystal dielectrics.
摘要:
A ferroelectric, liquid-crystalline polymer is composed of repeating units of the formula (I) ##STR1## in which Y=H, CH.sub.3 or F,R.sup.1 =a radical having at least two chiral centers such as for example ##STR2## a=2 to 20, preferably 6 to 12, b,c,d,e and f=0 or 1 with the proviso that d+e+f=2 or 3,A.sup.1,A.sup.2 and A.sup.3 =for example, 1,4-phenylene, cyclohexylene or 2,5-pyrimidinediyl,M.sup.2 and M.sup.3 =CO--O, O--CO, CO--S, S--CO, CH.sub.2 --O, O--CH.sub.2, and ##STR3## These liquid-crystalline polymers have short response times and resistance to mechanical stresses.They can be prepared by free-radical polymerization.
摘要翻译:铁电液晶聚合物由式(I)的重复单元组成,其中Y = H,CH 3或F,R 1 =具有至少两个手性中心的基团,例如 a = 2至20,优选6至12,b,c,d,e和f = 0或1,条件是d + e + f = 2或3,A1,A2和A3 =例如,1,4-亚苯基 ,亚环己基或2,5-嘧啶二基,M2和M3 = CO-O,O-CO,CO-S,S-CO,CH2-O,O-CH2和这些液晶聚合物具有较短的响应时间 和耐机械应力。 它们可以通过自由基聚合制备。