US Patent 7892629 Laminated glazing material

A laminated glazing material with properties of acoustic insulation and mechanical strength. The laminated glazing material including two glass sheets and a single-ply intermediate layer of a thickness having the form of a polymer film. The thickness of the intermediate layer being defined as a function of a variable which is specific to the material, and which defines the critical energy value of the intermediate layer and is representative of the energy necessary for propagation of a crack initiated in the intermediate layer.