Abstract: The thin-film electroluminescent device of the present invention comprises a thin film of a polyoxadiazole derivative represented by the formula: ##STR1## wherein each of X.sub.0 and Y.sub.0 independently represents a divalent organic group which may comprise a silicon atom, and n is an integer of 2 or greater,formed as an electroluminescent layer or a charge injecting/transporting layer between electrodes, at least one thereof being transparent. This thin-film electroluminescent device is excellent not only in electroluminescence and capability of charge injection/transport to thereby ensure high light emission efficiency but also in durability such as heat resistance.

Abstract: There is provided a carboxylic acid compound represented by the following formulae (I) to (IV): ##STR1## a liquid crystal material consisting of the carboxylic acid ester compound, a liquid crystal composition comprising the carboxylic acid ester compound, and a liquid crystal element using the carboxylic acid ester compound. There can be obtained advantages such as low operating temperature, high speed switching, very small electric power consumption, and high-stable contrast.

Abstract: There is provided a carboxylic acid compound represented by the following formulae (I) to (IV): ##STR1## a liquid crystal material consisting of the carboxylic acid ester compound, a liquid crystal composition comprising the carboxylic acid ester compound, and a liquid crystal element using the carboxylic acid ester compound. There can be obtained advantages such as low operating temperature, high speed switching, very small electric power consumption, and high-stable contrast.

Abstract: A novel hydrazine compound represented by the formula (I) is disclosed. ##STR1## Also disclosed are a process for preparing the novel hydrazine compound comprising reacting a specific hydrazine compound and a specific acid halide, a nonlinear optical organic material comprising the hydrazine compound represented by the above formula (I), and a nonlinear optical organic element comprising the nonlinear optical organic material. The nonlinear optical organic material shows excellent nonlinear optical effect, and the material is favorably applied to nonlinear optical organic elements such as an optical wavelength conversion element and an electrooptical element.

Abstract: An antiferroelectric liquid crystal composite material comprising an organic polymer and an antiferroelectric liquid crystal material, both being in the dispersed state; a process for preparing a liquid crystal element including a step of mixing an organic polymer and an antiferroelectric liquid crystal material; and a liquid crystal element having such a structure that the above-mentioned antiferroelectric liquid crystal composite material is sandwiched between a pair of electrodes are provided. According to the present invention, there can be obtained a liquid crystal element which is available at a low price, quick in the electrooptical response, free from occurrence of switching failure and is able to make a large display screen.

Abstract: In accordance with the present invention, there are provided carboxylate compounds represented by the following formula [A] and liquid crystal material comprising said compounds ##STR1## wherein R is a group selected from the group consisting of alkyl, alkoxy and halogenated alkyl group of 3-20 carbon atoms, X and Y represent each a group selected from the group consisting of --COO--, --OCO--, --CH.sub.2 CH.sub.2 --, --CH.sub.2 O--, --OCH.sub.2 --, --S--S--, ##STR2## or a single bond, A and B represent each a group selected from the group consisting of specific divalent aromatic and alicyclic group such as phenylene, cyclohexylene and tetrahydronaphthalene and R* is an optically active group of 4-20 carbon atoms containing at least one asymmetric carbon atom (hydrogen atoms attached to the carbon atoms of said optically active group may be substituted with halogen atoms), and m and n are each an integer of 0-2, with the proviso that both m and n do not become 0 at the same time.

Abstract: The liquid crystal composition of the present invention comprises 1-99 wt. % of an antiferroelectric liquid crystal compound such as a compound represented by the following formula [A-8] and 99-1 wt. % of a cholesteric liquid crystal compound such as a compound represented by the following formula [B-2]. ##STR1## By the use of the liquid crystal composition of the invention, a liquid crystal element improved in liquid crystal properties such as contrast can be prepared.

Abstract: In accordance with the present invention, there are provided carboxylate compounds and liquid compositions thereof represented by the following formula (A) ##STR1## wherein R.sup.1 represents one group selected from the group consisting of alkyl group having 6 to 18 carbon atoms, alkoxy group having 6 to 18 carbon atoms and halogenated alkyl group of 6 to 18 carbon atoms, C* represents an asymmetric carbon atom, and R.sup.2 represents a group represented by the following formula (A)--(CH.sub.2).sub.m --CH.sub.3 or (B)--(CH.sub.2).sub.n --COOR.sub.3 wherein m represents an integer of 2 to 6, n represents an integer of 0 to 5, and R.sup.3 represents alkyl group having 1 to 10 carbon atoms.

Abstract: The liquid crystal racemic mixture of the invention is represented by the formula [I]:Z--(X.A).sub.m (Y.B).sub.n COOR.sup.1 [I]wherein R1 is a specific group of alkyl, alkoxy or halogenated alkyl, X and Y are either one of the following group: --COO--, --OCO--, --CH.sub.2 CH.sub.2 --, --CH.sub.2 O--, --OCH.sub.2 --, --COCH.sub.2 --, --CH.sub.2 CO-- and --S--S--, or a single bond, A and B are each a specific bivalent group such as 1,4-phenylene group, Z is a group selected from the group consisting of ##STR1## (wherein R.sub.2 is an alkyl group, an alkoxy group or a halogenated alkyl group), and m and n are an integer of 0 to 2 (m and N not being simultaneously 0). The liquid crystal composition of the invention comprises the racemic mixture as described above. Moreover, the liquid crystal element of the invention comprises a liquid crystal material containing the liquid crystal racemic mixture as described above.

Abstract: A naphthalene compound having the following formula (I) and a liquid crystal composition containing the same: ##STR1## wherein X represents a hydrogen atom or a halogen atom, Y and Z independently represent a monovalent group selected from the group consisting of ##STR2## wherein W represents a hydrogen atom or a halogen atom, R represents an alkyl group having 6 to 18 carbon atoms, provided that Y and/or Z represent the alkyl group, which is an optically active group including an asymmetric carbon having the following formula (II): ##STR3## wherein A is a group or atom selected from the group consisting of alkyl groups, alkoxy groups, halogen atoms and fluoroalkyl groups, n is an integer of 0 to 3, m is an integer of 3 to 6, and *C represents an asymmetric carbon.

Abstract: In accordance with the present invention, there are provided photo-recording media comprising photochromic compounds having been dispersed or dissolved in stretched films or nematic liquid crystals, the transition moment of light absorption of said photochromic compounds being orientated in a definite direction. In the photo-recording media as provided, an information recorded in the photochromic compounds can be read out without destroying the same.

Abstract: In accordance with the present invention, there is provided substituted naphthalene compounds represented by the following formula [I]. ##STR1## wherein R.sup.1 represents alkyl of 1-18 carbon atoms, R.sup.2 represents alkyl of 1-18 carbon atoms, X is a group represented by --OCH.sub.2 -- or --CH.sub.2 CH.sub.2 --, and n is 0 or 1.In accordance with the invention, moreover, there is provided liquid crystal compositions containing the substituted naphthalene compounds represented by the above-mentioned formula [I].

Abstract: In accordance with the present invention, there is provided substituted naphthalene compounds represented by the following formula [I]. ##STR1## wherein R.sup.1 represents alkyl of 1-18 carbon atoms, R.sup.2 represents alkyl of 1-18 carbon atoms, X is a group represented by --OCH.sub.2 -- or --CH.sub.2 CH.sub.2 --, and n is 0 or 1.In accordance with the invention, moreover, there is provided liquid crystal compositions containing the substituted naphthalene compounds represented by the above-mentioned formula [I].