Cyclobutane benzene derivatives

Details Cyclobutane benzene derivatives Cyclobutane benzene derivatives

1994-07-20

1995-08-29

Wu, Shean

Compositions

Liquid crystal compositions

Containing nonsteryl liquid crystalline compound of...

25229961, 25229962, 560123, 570127, 359103, C09K 1930, C09K 1934, C07C 2518, G02F 113

Patent

active

054457645

DESCRIPTION:

BRIEF SUMMARY
SUMMARY OF THE INVENTION

The invention relates to cyclobutane benzene derivatives of the formula I ##STR2## in which
R.sup.1 is alkyl or alkenyl having 1 to 16 carbon atoms, in which additionally one or more CH.sub.2 groups may be replaced by --O--, or is a group of the formula ##STR3## in which
R.sup.2 is alkyl or alkenyl having 1 to 16 carbon atoms, ##STR4##
O is 0 or 1,
V and W are each CH.sub.2 or CH.sub.2 CH.sub.2, and when V is CH.sub.2 CH.sub.2 m is 1, 2 or 3 and W is CH.sub.2,
A.sup.1 is at each occurrence, independently of the others, 1,4-phenylene which is unsubstituted or substituted by 1 to 2 fluorine atoms, in which, in addition, one or two CH groups may be replaced by N, or is 1,4-cyclohexylene which is unsubstituted or substituted by a cyano group, and in which, in addition, one or two CH.sub.2 groups may be replaced by O or S, or is thiadiazole-2,5-diyl, 1,4-bicyclo[2.2.2]-octylene, or a radical of the formula ##STR5##
L.sup.1 and L.sup.2 are each independently of one another H or F,
Z.sup.1 is --CO--O--, --O--CO--, --CH.sub.2 O--, --OCH.sub.2 --, --CH.sub.2 CH.sub.2 --, --C.ident.C-- or a single bond,
Y is NCS, halogen or an alkyl, alkoxy, alkenyl or alkenyloxy group having 1 to 8 carbon atoms which is substituted by at least one fluorine and/or chlorine atom, atoms, in which, in addition, 1 or more CH.sub.2 groups may be reacted [sic] by --O--,
m is 0, 1, 2 or 3, and
n is 0, 1 or 2.
The invention relates furthermore to the use of these compounds as components of liquid-crystalline media and to liquid-crystal and electrooptical display elements containing the liquid-crystalline media according to the invention.
The compounds of the formula I can be used as components of liquid-crystalline media, especially for displays which are based on the principle of the twisted cell, including their highly twisted variants, for example STN or SBE, on the guest-host effect, on the effect of the deformation of aligned phases or on the effect of dynamic scattering.
The object underlying the invention was to discover new, stable, liquid-crystalline or mesogenic compounds which are suitable as components of liquid-crystalline media and which, in particular, have a comparatively low viscosity and a moderate positive dielectric anisotropy.
It has now been found that compounds of the formula I are ideally suited as components of liquid-crystalline phases. In particular, they possess comparatively low viscosities. They can be used to obtain stable liquid-crystalline phases with a broad mesophase range and advantageous values for the optical and dielectric anisotropy, which are at the same time notable for highly favorable values for specific resistance and low viscosities. By this means it is possible, in particular, to attain definite advantages in media for active matrix displays or supertwist displays.
Japanese Published Application JP 02 085 243 discloses benzonitrile derivatives of the formula ##STR6## (n=1 or2).
GB 21 55 946 encompasses cyclobutane derivatives of the formula I, but only describes cyclobutanecarboxylic esters. These esters, however, are not suitable for active matrix displays.
Other similar cyclobutane derivatives are described by:
DE-A 37 17 484: ##STR7##
DE-A 39 29 524: ##STR8##
The general formula of WO 91/08184 includes benzene derivatives which have a group ##STR9## However, no cyclobutane derivatives are described therein.
Furthermore, the compounds described in the prior art only have moderate values for their optical anisotropy, whereas the compounds according to the invention possess distinctly lower optical anistropies and viscosities.
The provision of compounds of the formula I moreover represents, in quite general terms, a considerable broadening of the range of liquid-crystalline substances which are suitable, subject to various performance-related criteria, for the preparation of liquid-crystalline mixtures.
The compounds of the formula I possess a broad range of application. Depending on the choice of substituents these compounds can be used as base materials, of which liq

REFERENCES:
patent: 5384072 (1995-01-01), Poetsch et al.

Affiliated with

Also associated with

Rating

Cyclobutane benzene derivatives does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Cyclobutane benzene derivatives, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cyclobutane benzene derivatives will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1818090