Method for making flexible bags having elastic-like behaviour comprising regions formed into pleat elements

摘要

A method of forming flexible bags from a continuous web is disclosed. The method includes introducing a continuous web of sheet material and passing it through a process whereby the flexible bag is formed having elastic-like behavior. The continuous web is processed into a continuous web having at least two regions that are visually distinct. A sheet material is introduced having one portion of the sheet material overlapping another portion of the sheet material. The sheet material is formed into a strainable network. The strainable network includes a plurality of first regions and a plurality of second regions. The first regions are substantially un-deformed and the second regions are formed into disengageable pleat elements. As the overlapped portions of the sheet material are formed they engage each other at the pleat elements. The pleat elements of each overlapped portion become engaged within each other and resist disengagement because of the frictional forces of the sheet material. The overlapped portions of the sheet material are separated using a disengaging means so that the overlapped portions become disengaged and are separated from each other while riding on the disengaging means. The disengaging means is in the form of either air knife, static opening bar, dynamic opening bar, or suction means, and any combinations thereof.