摘要:
A fluorine-containing optically active compound represented by the formula (1): ##STR1## wherein R.sub.1 is a saturated or unsaturated C.sub.3 -C.sub.20 alkyl group or a saturated or unsaturated C.sub.3 -C.sub.20 alkoxyalkyl group; A.sup.1, A.sup.2 and A.sup.3 independently represent one of the following groups: ##STR2## provided that, when A.sup.1 is a condensed ring group, a sum of p and q is 0 or 1 and A.sup.2 and A.sup.3 are both monocyclic groups, or when A.sup.1 is a monocyclic group, a sum of p and q is 1 or 2 with the proviso that when the sum of p and q is 2, A.sup.2 and A.sup.3 are both monocyclic groups; X is --CH.sub.2 CH.sub.2 --, --CH.dbd.CH-- or --C.tbd.C--; W is a fluorine atom or a hydrogen atom; n is an integer of 1 to 10; m, p and q are each 0 or 1; u and w are each an integer of 0 to 3; and * indicates an asymmetric carbon atom, which is useful as a component of a liquid crystal mixture.
摘要:
A liquid crystal mixture containing (a) at least one compound of a compound of the formula (1): ##STR1## in which R is a C.sub.1 -C.sub.12 alkyl group, etc.; X.sub.1, X.sub.2, X.sub.3, X.sub.4, Y.sub.1, Y.sub.2, Y.sub.3 and Y.sub.4 represent, independently each other, CH, CF or N; A is a hydrogen atom, a 4-R.sub.1 -(cycloalkyl) group, etc. in which R.sub. is a C.sub.1 -C.sub.12 alkyl group, etc. and p is 0 or 1; and Z is --C.tbd.C-- or a single bond, and (b) at least one compound of the formula (4): ##STR2## wherein rings C, D, E and F represent, independently each other, 1,4-phenylene, etc. which may be substituted by 1, 2 or 3 fluorine atoms; R.sub.2 is a hydrogen atom, a C.sub.1 -C.sub.12 alkyl group, etc.; R.sub.3 is a hydrogen atom, a fluorine atom, a fluoromethyl group, etc.; Z.sub.1, Z.sub.2 and Z.sub.3 represent, independently each other, --COO--, --OCO--, --OCH.sub.2 --, --CH.sub.2 O--, a C.sub.1 -C.sub.5 alkylene group, a C.sub.2 -C.sub.5 alkenylene group, etc.; J and K represent, independently each other, a methylene group or --O--; a, b, c, d and e represent, independently each other, 0 or 1.
摘要:
A ferroelectric chiral smectic liquid crystal mixture comprising at least one compound of the formula (I): wherein R11 and R12 represent, independently each other, a C1-C20 alkyl, alkoxy or alkoxyalkyl group which may be substituted by at least one halogen atom and may have an unsaturated bond; A11, A12 and A13 represent, independently each other, a phenylene group which may be substituted by a fluorine atom, or the like; * indicates an asymmetric carbon atom; Z is a hydrogen atom or a fluorine atom; n is an integer of 0 to 10; r, s, t and u are each 0 or 1, provided that when u is 1, the compound (I) is a trans-olefin, and at least one compound of the formula (II): wherein R21 is a saturated or unsaturated C3-C20 alkyl group or a saturated or unsaturated C3-C20 alkoxyalkyl group; A21, A22 and A23 represent, independently each other, a phenylene group which may be substituted by a fluorine atom or the like; X2 is —C≡C— or the like; Z is a hydrogen atom or a fluorine atom; n is an integer of 1 to 10; m is 0 or 1; and * indicates an asymmetric carbon atom, which liquid crystal mixture has a high response speed and a small dependency of &tgr;-Vmin characteristic on temperature and a wide temperature driving margin.
摘要:
A diphenylacetylene compound of the formula [1]: ##STR1## wherein R is a C.sub.1 -C.sub.12 alkyl group, a C.sub.2 -C.sub.12 alkenyl group or a C.sub.2 -C.sub.16 alkoxyalkyl group; X.sup.1, X.sup.2, X.sup.3, X.sup.4, Y.sup.1, Y.sup.2, Y.sup.3 and Y.sup.4 are independently from each other a --CH-- group, a --CF-- group or a nitrogen atom;A is a hydrogen atom, a fluorine atom, a trifluoromethyl group, a trifluoromethoxy group, a cyano group, a 4-R.sup.1 -(cycloalkyl) group, 4-R.sup.1 -(cycloalkenyl) group or a R.sup.1 --(O).sub.m group in which R.sup.1 is a C.sub.1 -C.sub.12 alkyl group, a C.sub.2 -C.sub.12 alkenyl group or a C.sub.2 -C.sub.12 alkynyl group; and m is 0 or 1, which has an excellent anisotropy of refractive index and a low viscosity and is useful as a component of a liquid crystal composition.
摘要:
There is disclosed a process of producing a 2-cyano-4-oxo-4H-benzopyran compound of the general formula (2): ##STR1## wherein R.sup.1 and R.sup.2 are independently hydrogen, halogen, hydroxy, C.sub.1 -C.sub.5 alkyl, C.sub.1 -C.sub.5 alkoxy, nitro or a group of the RCONH wherein R is C.sub.1 -C.sub.20 alkyl, phenyl, phenyl-substituted (C.sub.1 -C.sub.20) alkyl, phenyl (C.sub.1 -C.sub.20)alkoxyphenyl or (C.sub.1 -C.sub.20) alkoxyphenyl. This production process is characterized in that a carboxamide of the general formula (1): ##STR2## wherein R.sup.1 and R.sup.2 are each as defined above, is reacted with a dehydrating agent in the presence of a pyridine compound of the general formula (4): ##STR3## wherein A.sup.1 and A.sup.2 are independently hydrogen or C.sub.1 -C.sub.5 alkyl. If the final product cannot be obtained as crystals having good filtration properties by ordinary treatments, a novel technique as disclosed herein can provide such crystals by dissolving the reaction product in an organic solvent insoluble or slightly soluble in water; pouring the resultant solution into water; and removing the organic solvent by distillation with stirring to effect the crystallization of the final product.
摘要:
A 1-bromoalkylbenzene derivative is prepared by reacting a phenylalkene derivative with hydrogen bromide in the presence of a non-polar solvent. The phenylalkene derivative is prepared by reacting an alkenyl halide with metal magnesium to form a Grignard reagent, and then reacting the Grignard reagent with a benzyl halide derivative. An allyl Grignard reagent is prepared by reacting continuously an allyl halide derivative with metal magnesium in an organic solvent, in which the allyl halide derivative and metal magnesium are continuously added to the reaction system and the allyl Grignard reagent formed is continuously removed from the reaction system. The processes provide the intended compounds in high yields, high selectivities and high purities.
摘要:
A 1-bromoalkylbenzene derivative is prepared by reacting a phenylalkene derivative with hydrogen bromide in the presence of a non-polar solvent. The phenylalkene derivative is prepared by reacting an alkenyl halide with metal magnesium to form a Grignard reagent, and then reacting the Grignard reagent with a benzyl halide derivative. An allyl Grignard reagent is prepared by reacting continuously an allyl halide derivative with metal magnesium in an organic solvent, in which the allyl halide derivative and metal magnesium are continuously added to the reaction system and the allyl Grignard reagent formed is continuously removed from the reaction system. The processes provide the intended compounds in high yields, high selectivities and high purities.
摘要:
A motor control device with which both high-accuracy current detection and improvement in voltage utilization factor are achieved is provided. When an ON time of any one of low potential side switching elements corresponding to respective phases in a driving circuit is shorter than a detection time of a current value, a microcomputer estimates a phase current value of a current undetectable phase based on current values of two phases other than the current undetectable phase corresponding to the said FET. Then, at the time of current detection using the blind correction, during current detection for two phases, other than the current undetectable phase, based on which the blind correction is performed, motor control signals for maintaining switching states of a switching arm corresponding to the current undetectable phase are output.
摘要:
A motor control device with which both high-accuracy current detection and improvement in voltage utilization factor are achieved is provided. When an ON time of any one of low potential side switching elements corresponding to respective phases in a driving circuit is shorter than a detection time of a current value, a microcomputer estimates a phase current value of a current undetectable phase based on current values of two phases other than the current undetectable phase corresponding to the said FET. Then, at the time of current detection using the blind correction, during current detection for two phases, other than the current undetectable phase, based on which the blind correction is performed, motor control signals for maintaining switching states of a switching arm corresponding to the current undetectable phase are output.
摘要:
A time stamp generating system has a time distribution server for generating time data depending on time and a user PC for holding time certification objective digital data. The time distribution server generates time data corresponding to a time point and distributes the time data. The user PC calculates time stamp generating data by using the time certification objective data as an input, acquires the time data generated by the time distribution server, and processes the time data on the basis of the time stamp generating data to obtain a time stamp.