To prevent the swelling of a film during the conveyance of the film while blowing drying air to the film to float the film.

A drying duct 48 is provided under the wet film 25a. The drying duct 48 includes: the duct body 50; a drying air supply part 52; an exhaust pipe 53; and an exhaust quantity control part 54. The drying air supply part 52 supplies the drying air 56 to the duct body 50. The drying air 56 is blown to the wet film 25a through blowout holes 57a. An exhaust hole 53a is provided in a position opposed to nearly the width-direction center part of the wet film 25a. Among the drying air 56 flowing beneath the wet film 25a, the drying air 56a flowing in a part corresponding to nearly the width-direction center part of the wet film 25a is exhausted into the exhaust pipe 53 by means of the exhaust hole 53a. The drying air 56a is exhausted outside through an exhaust hole 53b. The exhaust quantity of the drying air 56a is controlled by the exhaust quantity control part 54.