A rotary disc atomizer having a disc having an axis and rotatable about the axis, the disc also having two opposite surfaces as considered in an axial direction, and a peripheral edge, the disc having a plurality of throughgoing openings so that when a liquid is supplied to one of the surfaces and flows toward the edge and then droplets are sprayed, the liquid also flows through the throughgoing holes to another of the surfaces so as to also flow radially outwardly on the other surface and form droplets thrown from the edge in a region of the other surface.