The invention relates to a substrate, a method for spraying particulate solids onto a substrate and an apparatus for spraying particulate solids onto a substrate covered with a wet and/or adhesive synthetic resin layer, comprising a feed line having means for generating a gas pressure at its first end and a free opening at its second end, a reservoir for particulate solids, and a nozzle for generating a pressure differential, wherein the reservoir and the nozzle are inserted in the line in such a way that particulate solids are taken out of the reservoir into the line and swirled, and transported to the open end of the line, from which the particulate solids are ejected and sprayed onto the wet and/or adhesive synthetic resin layer, by the pressure differential generated by the nozzle in operation.