Abstract: A structurally coated silica can be prepared by spraying and mixing a pyrogenic silica with water and a coating agent in a suitable mixing vessel, then milling and then conditioning the product. The structurally coated silica can be used as a matting agent in lacquers.

Abstract: The hollow profiles with inner reinforcement are especially suited for use in automobile bodies. The aim of the invention is to ensure that an anti-corrosion medium reaches all areas and to obtain rigidity in a hollow structure without increasing the weight of the profile or enlarging its cross-section. To this end, a solid core material is coated with an activable material and an outer panel is arranged in such a way as to form a hollow space which can be filled through the foaming action of the activable material. The size of this hollow space is determined by how the spacers are determined and by how the spacers are arranged, depending on the particular application. The solid core material consists of a foamed or non-foamed metallic material or of a synthetic material reinforced with metal fibers, carbon fibers or glass fibers.