Triphenylene derivs. of formula (A) are new. In (I), R = 2-20C alkyl; X = F, Cl, Br, I, NO2, CN, CHO, Ar-N=N- (Ar = (het)aryl), a 2-20C aliphatic gp. or araliphatic gp. with up to 20C attached to the triphenylene by a C or S atom or sulphonyl(oxy) gp.; Y, Z = -OR or X. Also claimed are intermediates of formula (A; X, Y = H).