Abstract: The present invention provides a dye solution of anthraquinone blue dyes in a non-polar organic solvent, which dyes are a mixture of dyes of the general formulae: ##STR1## where the Rs on each compound are selected from the group consisting of 2-ethylhexyl, mixed amyl, n-butyl and methyl, and wherein said dye mixture is the reaction product of quinizarin and/or leuco quinizarin and between about 15 and about 35 mole % of each of 2-ethylhexylamine, n-butylamine, amylamine and methylamine. The dye solutions, at high concentrations, are stable at low temperatures. These dye solutions also provide high tinctorial strength.

Abstract: To produce a concentrated solution of aminoanthraquinone dyes in aromatic solvent, quinizarin or a leuco derivative thereof is reacted with a mixture of at least three aliphatic amines in a solvent which is a glycol or a glycol ether. The glycol or glycol ether solvent is present in an amount of 50 wt % or less relative to the quinizarin or leuco derivative plus amines. After the reaction, water and excess amine are stripped and aromatic solvent is added to adjust the dye concentration to the desired concentration above 40 wt % dye.