The present invention relates to a formulation containing at least one organic functional material and at least four different organic solvents, a first organic solvent A, a second organic solvent B, a third organic solvent C, and a fourth organic solvent D, wherein the first organic solvent A comprises a group, which is capable of receiving or giving a hydrogen bonding, the second organic solvent B has a boiling point in the range from 50 to 350° C., the third organic solvent C has a boiling point in the range from 100 to 300° C., and the fourth organic solvent D has a boiling point in the range from 200 to 400° C., is present in an amount from 0.01 to 1 vol.-% and has a viscosity of ≥15 mPas, the solubility of the at least one organic functional material in the second organic solvent B and in the fourth organic solvent D is ≥5 g/l, the boiling point of the third organic solvent C is at least 10° C. lower than the boiling point of the second organic solvent B; and the boiling point of the fourth organic solvent D is at least 10° C. higher than the boiling point of the second organic solvent B; as well as to electroluminescent devices prepared by using these formulations.