device in the form of a suction device c and a steaming machine d the applicator a comprises a vertical gap 2 that extends over the width of the web 10 this gap 2 is filled up to a filling level 3 with a liquid preparatory agent that is continuously supplied from supply conduits 21 the quantity of liquid contained in the gap 2 is small if the working width of the gap is 4 m the quantity of liquid is about 25 liters the web 10 is guided vertically over guide rolls 5 and 6 from the top to the bottom and through the gap 2 the web absorbs the preparatory agent in the gap 2 which is subsequently wiped off from both sides of the web 2 by two inflatable tubes 7 disposed below the gap 2 the inflatable tubes 7 extend across the width of the web 10 these tubes 7 define and seal the bottom end of gap 2 so that no significant quantities of the preparatory agent can run downward and out of the gap 2 the web 10 is next led over the driven deflecting roll 8 which provides the necessary amount of tension to guide the web 10 through the gap 2 as well as over a compensator 9 before feeding the web 10 into the dwell apparatus b in the embodiment shown in the figure the dwell apparatus b includes a series of four upper deflecting rolls 11 which are all arranged at the same height and parallel to one another the dwell apparatus b also includes a series of three deflecting rolls 12 spaced vertically below and horizontally offset from.