Abstract: A multilayer composite body includes thermoplastic layers and layers of natural fibers bound with thermoplastic synthetic material. The composite body has at least one reinforcing layer made of an open-cell fabric of melting fibers. The reinforcing layer is penetrated on one or both sides by the melting thermoplastic synthetic material of adjoining natural-fiber layers and is integrated there for reinforcement. The reinforcing layer can also be disposed in addition or only between natural-fiber and pure thermoplastic layers or between thermoplastic layers. Such a composite body has excellent mechanical properties, in particular with regard to bending stress and impact resistance.

Abstract: A sound and heat insulation material for insulating buildings, motor vehicles, conduits, etc., is covered on at least one exterior surface with a material which reacts at a given temperature by foaming up, and which is difficult to ignite or inflammable. The exterior covering can be a sheet or fiber layer which is impregnated with the reactive material or coated with it. The fibers of the sound and heat insulation core layer can also be directly coated with the reactive material or be mingled with a variable proportion of foamable fibers. The sound and heat insulation element, which is difficult or impossible to ignite, has good insulating properties.