Abstract: A material composite for the production of a stiffening member for lightweight construction by means of thermoforming includes a cellulose-based core made of a wavy paper web or having a honeycomb structure and a kraftliner, which is mechanically connected to the wavy paper web or the honeycomb structure and which in turn comprises a planar paper web. An adhesive layer is disposed between the planar paper web of the kraftliner and the core, which mechanically connects the planar paper web to the core. Furthermore, a stiffening member for lightweight construction is produced on the basis of the material composite and a production method suitable for this purpose.

Abstract: A three-dimensionally contoured, acoustically effective heat shield for a motor vehicle, includes a heat reflection layer made of a metallic material, such as aluminum, and an acoustic insulation layer made of a thermoformable, rubber-elastic and thermoplastic material, and a hot-melt adhesive film made of a polymer material. The adhesive film is disposed between the heat reflection layer and the insulation layer and forms a plane mechanical connection between the heat reflection layer and the insulation layer. A method for producing the three-dimensionally contoured, acoustically effective heat shield includes the steps of providing a two-dimensionally extending material composite and thermoforming the composite in a thermoforming tool, in which at least one mold half has a molding tool temperature that is above the activation temperature of the heat-activatable adhesive film and above the melting temperature of the rubber-elastic material of the insulation layer.