Abstract: In the developing station of a processing system for printing plates, a counter-roller is offset with respect to the brush roller in the plane of passage of the printing plates by a given distance "a". In another embodiment, the transport rollers are lowered by an amount "b" with respect to the plane of passage which extends horizontally between the gap between the brush roller and the counter-roller.

Abstract: When developing a coating such as for instance a light-sensitive exposed layer on a length or plate of material through ultrasonic agitation, the material is carried at a short distance or closely past a bar or a pipe extending substantially perpendicular to the advancing direction of the material and in the entire width of the coating. The bar or the pipe is caused to vibrate by a plurality of ultrasonic transducers while a developer is applied onto the coating adjacent the bar or the pipe in such a manner that the vibrations are transferred from the vibrating bar or pipe to the developer and to a stripe-shaped transverse area of the plate/the length including the coating. In this manner only the part of the developer having touched the ultrasonically agitated pipe or bar or already having hit the stripe of material currently developed is caused to vibrate by the ultrasonic transducers.