Method for preparing a semiconducting layer

A method for preparing a semiconducting layer of an organic electronic device comprising: (i) depositing said semiconducting layer from a solution comprising a polymeric semiconductor, a non-polymeric semiconductor, a first aromatic solvent and a second aromatic solvent, wherein said second aromatic solvent has a boiling point that is at least 15° C. higher than the boiling point of said first aromatic solvent; and (ii) heating said deposited layer to evaporate said solvent, wherein said first aromatic solvent is of formula (I): wherein R1 is selected from C1-6 alkyl and OC1-6 alkyl; and R2 and R3 are each independently selected from H and CC1-6 alkyl.