PURPOSE: To control the size of adhesive droplets by providing a sprayer with a means for discharging the jet of a molten thermoplastic adhesive from a discharge orifice, a means for finely breaking up the adhesive jet to droplets by injecting a spray air stream to the outside of this adhesive jet and a flow rate control means for the sprayed air stream.

CONSTITUTION: A plunger control valve 186 and a prepressurized air control valve 68 are operated to supply the spray air to the region of a nozzle tip 126 prior to the start of the flow of the adhesive passing a nozzle. The adhesive stream 188 is then ejected from the discharge orifice 180 and meets the spray air injected from a spray air discharge flow passage 128. This spray air expands outward radially from the discharge flow passage 128 and collides against the outside surface of the adhesive stream 188 at a sufficient flow rate and velocity. As a result, the adhesive is finely ground to the adhesive steam 188 and the droplets 190 which deposit on a substrate 192. Further, the droplets 190 receive the collision of the pattern forming air ejected from the discharge orifice 146 of an air horn 148, there by, the pattern width of the droplets 190 deposited on the substrate 192 is controlled.