Stable liquid formulation
The present invention concerns concentrated aqueous solutions of an anionic disazo dye, comprising salts and or the free acids of the anionic dye of the formula (I) and 2-(2-butoxyethoxy)ethanol and the use of these solutions for dyeing and/or printing hydroxyl-containing substrates and for producing inkjet inks.
1. A concentrated aqueous solution comprising salts or the free acid of the anionic dye of the formula (I) or both,
2-(2-butoxyethoxy)ethanol and a water-soluble organic solubilizer, wherein the water-soluble organic solubilizer is urea present in an amount of 1-6% by weight.
2. The concentrated aqueous solution according to claim 1 , wherein the concentrated aqueous solution comprises 5% to 40% by weight of the dye of the formula I.
3. The concentrated aqueous solution according to claim 1 , comprising
10-12% by weight of the anionic dye of the formula (I), wherein the anionic dye is in the form of a free acid,
1-8% by weight of 2-(2-butoxyethoxy)ethanol,
1-6% by weight of a water-soluble organic solubilizer and
74-88% by weight of water.
4. An ink jet ink comprising a concentrated aqueous solution according to claim 1 .
5. A method of utilizing a concentrated aqueous solution according to claim 1 for dyeing and/or printing hydroxyl-containing substrates and for producing inkjet inks comprising the step of adding the concentrated aqueous solution to the dyed and/or printed hydroxyl-containing substrate or the inkjet ink during production thereof.
6. A hydroxyl-containing substrate dyed or printed with a concentrated aqueous solution according to claim 1 .
7. The hydroxyl-containing substrate according to claim 6 wherein the hydroxyl-containing substrate is paper.