Coarse-structured material web e.g. bulge-or arch structured material web, producing method for e.g. receiving sound absorbing layer, involves forming fine structure in inner boundary region, and forming flat or virtual flat edge

摘要

The method involves actuating upper and lower supporting elements against an inner boundary region (5) of a material web (1). A fine structure is formed in the inner boundary region, where ruffling of the inner boundary region is bigger than ruffling of a coarse-structured centric region. A flow of material from an external boundary region (9) is produced in the direction of the inner boundary region, where the external boundary region is arranged in the inner boundary region. The structure is formed in the inner boundary region, and a flat or virtual flat edge (11) is formed. An independent claim is also included for a three-dimensional structured material web comprising a recess.