Abstract: The novel liquid crystal compounds of the present invention are represented by the following formulas ?I!-?II! and have tristable molecular orientation states and can be used for display devices and electrooptical devices. ##STR1## wherein R.sub.1 represents an alkyl group of 5-18 carbon atoms; R.sub.2 represents an alkyl group of 6-16 carbon atoms; R.sub.3 represents an alkyl group of 8-18 carbon atoms; R.sub.4 represents an alkyl group of 6-14 carbon atoms; Y represents ##STR2## and * indicates an optically active center.

Abstract: A liquid crystal compound represented by formula (I): ##STR1## wherein R.sub.1 represents an alkyl group having from 3 to 18 carbon atoms; R.sub.2 represents an alkyl group having from 3 to 18 carbon atoms; X represents ##STR2## Y represents ##STR3## (A) and (B) each represents a group selected from the group consisting of ##STR4## and ##STR5## and * indicates an optically active center.

Abstract: The invention discloses optically active liquid crystal compounds represented by the formulas [I], [II] and [III]: ##STR1## wherein R.sub.1 and R.sub.2 each represents an alkyl group of 4-18 carbon atoms, X represents O, COO or a single bond, and (A), (B), (C), (D) and (E) each represents ##STR2## in which l represents a halogen. The invention further discloses optically active liquid crystal compounds which are able to exhibit tristable states, represented by the formulas [IV], [V] and [VI]: ##STR3## wherein R.sub.1 ' and R.sub.2 ' each represents a straight chain alkyl group of 5-16 carbon atoms, X' represents O or COO and (A), (B), (C), (D) and (E), and l each has the same meaning as above.

Abstract: Disclosed are novel liquid crystal compounds containing a naphthalene ring, having an excellent light leaking ratio at tristable states, and represented by the following formula: ##STR1## wherein R.sub.1 is a C.sub.6 -C.sub.16 linear alkyl group or C.sub.6 -C.sub.16 linear alkoxy group, R.sub.2 is a C.sub.4 -C.sub.12 linear alkyl group, R.sub.3 is a C.sub.1 -C.sub.3 alkyl group or C.sub.1 -C.sub.3 haloalkyl group, and C having an asterisk indicates an asymmetric atom.The liquid crystal compounds are expected to find their applications in electrooptical devices and liquid crystal displays utilizing a S*.sub.(3) liquid crystal phase which shows tristable states.

Abstract: Antiferroelectric liquid crystal compounds are provided which have the formula ##STR1## wherein R.sub.1 represents an alkyl group having 5-18 carbon atoms,R.sub.

Abstract: A liquid crystal compound represented by formula (I): ##STR1## wherein R.sub.1 represents an alkyl group having from 3 to 18 carbon atoms; R.sub.2 represents an alkyl group having from 3 to 18 carbon atoms; X represents ##STR2## (A) and (B) each represents a group selected from the group consisting of ##STR3## and * indicates an optically active center.

Abstract: Liquid crystal compound of the formula ##STR1## wherein R.sub.1 and R.sub.2 each is a C.sub.1-18 alkyl group or an aralkyl group, R' is a haloalkyl group, X is --0--, --CO--, --COO-- or direct bond, Y is --COO--, --OCO-- or --CH.sub.2 O--, (A) and (B) each is ##STR2## and p and l each is zero or one.

Abstract: A liquid crystal compound represented by formula (I): ##STR1## wherein R.sub.1 represents an alkyl group having from 1 to 18 carbon atoms; R.sub.2 represents an optically active group represented by formula (II), (III) or (IV): ##STR2## wherein R.sub.3 represents a lower halo-alkyl group having from 1 to 2 carbon atoms; X represents --O--, --COO--, --OCO-- or a single bond; Y represents --CH.sub.2 O-- or --COO--; and Z represents --COO-- or --O--, l represents 0 or 1, provided that when l is 0, Y is a single bond; n represents an integer of from 1 to 18; and * indicates an optically active center. The compound exhibits three stable states of molecular orientation.

Abstract: A new tetrastable liquid crystal is provided which is useful for display and switching devices. The liquid crystal has the formula ##STR1## where R.sub.1 is a C.sub.5-18 alkyl group and R.sub.2 is a C.sub.4-15 alkyl group and * is an optically active center.

Abstract: A liquid crystal compound represented by formula (I): ##STR1## wherein R.sub.1 represents an alkyl group having from 5 to 18 carbon atoms; R.sub.2 represents an alkyl group having from 4 to 15 carbon atoms; X represents a single bond, --O--, ##STR2## and * indicates an optically active center. The compound exhibits three stable states of molecular orientation.

Abstract: An optically active liquid crystal compound which is represented by the formula: ##STR1## wherein R.sub.1 and R.sub.2 each represents an alkyl or aralkyl group of 4-18 carbon atoms, R.sub.3 represents a haloalkyl group, X represents O, COO, OCO, CO or a single bond, Y represents COO, OCO, CH.sub.2 O or OCH.sub.2, Z represents COO or O, (A) represents a cyclic group shown by ##STR2## (B) represents a cyclic group shown by ##STR3## and l shows that the cyclic groups are substituted by at least one halogen atom.

Abstract: A liquid crystal compound represented by formula (I): ##STR1## wherein R.sub.1 represents an alkyl group having from 3 to 18 carbon atoms or an aralkyl group having from 7 to 18 carbon atoms; R.sub.2 represents an alkenyl group having from 1 to 18 (preferably from 3 to 14) carbon atoms; R.sub.3 represents CF.sub.3 or C.sub.2 F.sub.5 ; X represents a single bond, --O--, --COO--, or --OCO--; Y represents --COO--, --OCO--, --CH.sub.2 O--, or --OCH.sub.2 --; A and B each represents a cyclic group; and * indicates an optically active center.The compound of formula (I) exhibits three stable states of molecular orientation.

Abstract: An optically active compound represent by formula (I): ##STR1## wherein R.sub.1 represents a fluoroalkyl group having from 1 to 18 carbon atoms; R.sub.2 represents an alkyl group having from 1 to 16 carbon atoms and an aralkyl group having from 6 to 16 carbon atoms; R.sub.3 represents C.sub.2 F.sub.5, CF.sub.3, CHF.sub.2, or CH.sub.2 F; X represents a single bond, --O--, --COO--, or --OCO--; Y represents --COO--, --OCO--, --CH.sub.2 O--, or --OCH.sub.2 --; Z represents --COO-- or --O--; (A) and (B) each represent a cyclic group; and * indicates an optically active center, and a liquid crystal composition containing at least one of said optically active compounds are disclosed. The compound is useful not only as a liquid crystal compound but as a chiral dopant to provide a liquid crystal composition exhibiting a chiral smectic phase.

Abstract: An optically active fluorine-containing alcohol of ##STR1## where R.sub.2 is a C.sub.1-18 alkyl and n is 2-10, and liquid crystal compound of ##STR2## wherein R.sub.1 and R.sub.2 each is a C.sub.1-18 alkyl, X is O, COO or OCO, Y is COO, OCO, CH.sub.2 O or OCH.sub.2, Z is COO or O, (A) and (B) each is for example ##STR3## and p is zero or one, which is prepared from (I) above.

Abstract: There is disclosed herein a ferroelectric liquid crystal electro-optical apparatus of the maxtrix type comprising a liquid crystal cell having first and second electrode substrates which include n striped line electrodes and m striped column electrodes, respectively, facing at right angles each other. A ferroelectric liquid crystal is put in therebetween so as to form n by m indication picture elements. Also included in the apparatus a scanning drive device adapted to supply a scanning signal and a data signal to the n striped line electrodes and the m striped column electrodes, respectively. The ferroelectric liquid crystal shows three stable states in accordance with an application voltage and has a light transmittance with a hysteresis sufficient to a dynamic drive in accordance with increase or decrease in the application voltage in a predetermined voltage range.