The invention relates to a process for production of composite elements composed of at least one outer layer a) and of an rigid isocyanate-based foam b), where between the outer layer a) and the rigid isocyanate-based foam b) an adhesion promoter c) has been applied, and where the outer layer a) is continuously moved and the adhesion promoter c) and the starting material for the rigid isocyanate-based foam b) are applied successively to the outer layer, which comprises applying the adhesion promoter c) by means of a rotating plate which has been installed horizontally or with a deviation of up to 15° from horizontal, preferably parallel to the outer layer.