a spray nozzle assembly for atomizing a medium through a nozzle channel , comprising a first channel portion which is tapered by two lateral surfaces facing each other to form an elongate narrow cross - sectioned surface , a passage orifice disposed in the narrow cross - sectioned surface the cross - sectional area of which is smaller than is the narrow cross - sectioned surface , and a second channel portion adjoining the passage orifice in the direction of medium flow which has two opposed lateral surfaces separating from each other with an increase in distance from the passage orifice , whose edges facing the passage orifice extend crosswise to the longitudinal direction of the narrow cross - sectioned surface , characterized in that the nozzle channel having the two channel portions and the passage orifice are configured inside an integrally formed plastic component .