DOUBLED TRIPHENYLMETHANE DYES AND PIPERAZINE DERIVATIVES

摘要

O.Z. 0050/40869 Triphenylmethane dyes of the formula where each R1 is independently of the others hydrogen or sub stituted or unsubstituted C1-C6-alkyl, or two R1 radicals together with the nitrogen atom joining them form a heterocyclic radical, R2 and R5 is independently of the others hydrogen or C1-C4-alkyl, R3 and R4 is independently of the others hydrogen, C1-C4-alkyl, C1-C4-alkoxy or halogen, An.theta. is one equivalent of an anion, and n is 1 or 2, preparable from piperazine derivatives as intermediates, are useful for coloring paper.