METHOD AND TOOL FOR EMBOSSING OF BIODEGRADABLE PAPER TO FABRICATE CIGARETTE FILTERS

A method for embossing a sheet of substrate, wherein the embossing is realized by providing means of at least a first embossing roller and a second embossing roller configured to emboss first structures and second structures, thereby embossing the sheet of substrate when this passes in a nip formed by the first and second embossing rollers, whereby the embossed sheet of substrate is configured to be used in a manufacturing of cigarette filters, and is further configured to be entirely biodegradable. The method comprises providing a sheet of substrate. The method further comprises any one of the embossing steps in a list comprising: embossing the sheet of substrate with first structures to form crimping lines; embossing the sheet of substrate with second structures to form chimney structures; embossing the sheet of substrate with a combination of first and second structures to form crimping lines and chimney structures respectively. The crimping lines have a first width at a surface level of the sheet of substrate, and a first height or depth measured from the surface level in a first range of 0,1 mm to 0,5 mm, thereby configured to be deformable when used in the manufacturing process of cigarette filters. the chimney structures comprise segments that have a second width at the surface level of the sheet of substrate, in a second range of 0,5 mm to 5,0 mm, and a second height or depth measured from the surface level in a third range of 0,1 mm to 1,5 mm, thereby configured to remain open when used in the manufacturing process of cigarette filters and influence a pressure drop of air in such cigarette filters. Further the sheet of substrate comprises fibers with a cut length in a fourth range of 0,5 mm to 6,0 mm, and with a diameter in a fifth range of 10 µm to 500 µm, the fibers being entirely biodegradable and randomly distributed to deliver an air permeability. The sheet of substrate's air permeability being configured with filtration capabilities of substances present in a cigarette smoke. Procédé de gaufrage d'une feuille de substrat, le gaufrage étant réalisé au moyen d'au moins un premier rouleau de gaufrage et un second rouleau de gaufrage conçus pour gaufrer des premières structures et des secondes structures, ce qui permet de gaufrer la feuille de substrat lorsque celle-ci passe dans une fente formée par les premier et second rouleaux de gaufrage, grâce à quoi la feuille gaufrée de substrat est conçue pour être utilisée dans une fabrication de filtr