Substituted anthraquinone-type isotropic dyes for liquid crystal display devices

摘要

Certain substituted anthraquinone compounds have been found to be useful as isotropic dyestuffs in guest-host combinations with nematic, cholesteric and smectic liquid crystals and other well-known dichroic dyestuffs. By "isotropic" it is meant that the disclosed dyestuffs have optical order parameters (S) very close to zero. Use of the disclosed isotropic dyestuffs with additional well-known dichroic dyes in liquid crystal display devices, provides displays which alter between one colored state and another, depending upon the presence or absence of an electric field across the display.