The invention relates to a process for the production of composites, composed of at least one outer layer b) and of an isocyanate-based rigid foam a), where the outer layer b) is moved continuously and the starting material for the isocyanate-based rigid foam a) is applied to the outer layer b), which comprises achieving the application of the liquid starting material for the isocyanate-based rigid foam a) by means of at least one fixed tube c) which has openings f) and which has been placed, with respect to the outer layer b), so as to be parallel to the plane of the outer layer and at right angles to the direction of movement.