Abstract: A running substrate which is coated with a solvent-containing material is conveyed through several sections of a drying unit and is dried with a stream of inert gas which is conveyed counter to the direction of movement of the substrate. The temperature of inert gas is reduced during flow from section to section and the quantity of solvent in the inert gas is maintained slightly below saturation value during the initial stage of the drying operation to thus enhance the surface finish of the coating. The stream of inert gas is circulated along an endless path a portion of which coincides with the path for the substrate, and the inert gas is heated to maximum drying temperature before it enters the downstream end of the path for the substrate.