Patent ID: 8579782

Claim:
A method for applying a film around a window positioned in a continuous strip of paper ( 1 ), comprising: applying the film ( 3 ) for forming a frame ( 30 ) around the window ( 2 ), a total thickness of which is a sum of thicknesses of the continuous strip of paper ( 1 ) and the film ( 3 ), pressing at least the continuous strip of paper ( 1 ) at two parallel longitudinal stripes ( 20 ), arranged in margins at opposite sides of the window ( 2 ), with each of the stripes ( 20 ) having a sufficient width for containing a corresponding longitudinal side ( 30 L) of the frame ( 30 ), the pressing obtaining, at least at the longitudinal sides ( 30 L) of said frame ( 30 ), a total thickness which is not superior to an original thickness of the continuous strip of paper ( 1 ), wherein the parallel stripes ( 20 ) extend continuously from one end to another end of the continuous strip of paper ( 1 ).