Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar shape; Layered products comprising a layer having particular features of form
characterised by a particular shape of the outline of the cross-section of a continuous layer; characterised by a layer with cavities or internal voids; ; characterised by an apertured layer
characterised by an apertured layer, the apertures going through the whole thickness of the layer, e.g. expanded metal, perforated layer, slit layer regular cells B32B3/12
