The liquid crystal constituent and the liquid crystal component null which include the dichroism pigment and the said

摘要

PURPOSE: To obtain a dichroic dye exhibiting blue color, having high specific voltage retention and useful for active matrix liquid crystal display element, etc. ;CONSTITUTION: This dichroic dye is a compound having a trifluoromethoxyanilino group and expressed by formula I [A is a phenylene, trans-cyclohexylene, a (tetrahydro)naphthylene or trans-decahydronaphthylene; R is H, a halogen, an alkyl, an alkoxyalkyl, an alkoxy or a (substituted) cyclohexyl; (n) is 0 or 1], e.g. a compound of formula II. The compound of formula is produced e.g. by reacting 1-amino-4-bromoanthraquinone-2-carboxylic acid with trifluoromethoxyaniline in the presence of a copper catalyst and reacting the resultant compound of formula III with a compound of formula IV in the presence of an acid catalyst.;COPYRIGHT: (C)1995,JPO