a process for the production of a plate with a polymer frame shaped onto the edge of the plate . the frame is extruded onto the plate while the latter is held stationary in a working station of a handling automaton or robot with a support device which corresponds to the shape of the plate in such a way that the edge of the plate projects freely over the support face of the support device . with the aid of the robot , an extrusion die having a through , mouth - like slot with two jaws engages the top and bottom surfaces of the circumferential edge of the plate as the mouth - like slot engages the plate edge . at the front end of the two jaws of the die mouth , there are sealing ledges movable at right angles to the plate surfaces , which are supported on the latter during the extrusion process .