PURPOSE: To obtain a dyestuff mixture which, when used for dyeing or printing paper, gives a shade excellent in lightness and brightness with good light and wet fastness by incorporating two specific dyestuffs or their tautomers into the same.

CONSTITUTION: This mixture contains a dyestuff of formula I and a dyestuff of formula II (wherein R1 and R2 are each alkyl, cycloalkyl or aryl) and/or a tautomer of the dyestuff of formula I and/or a tautomer of the dyestuff of formula II. The mixture is esp. suitable for producing storage-stable conc. solns. of these dyestuffs, and the resultant soln. pref. contains 5-25 wt.% dyestuff of formula I and/or its tautomer, 0.2-5 wt.% dyestuff of formula II and/or its tautomer, and 94.8-70 wt.% water. The soln. does not contain additives other than triethanolamine and, if suitable, diethanolamine and lithium hydroxide. A pref. example of the dyestuff of formula II is one of formula III.