Bag and method of making the same

摘要

The plastic bag may include flexible thermoplastic sidewalls that have a pattern imparted onto them. The wrinkle pattern may be a plurality of linear ribs formed into the sidewall that may be arranged adjacent and parallel to one another. To impart the pattern to the sidewall, a thermoplastic web used to make the sidewall may be directed between a first cylindrical roller and a second cylindrical roller, each of which may have a plurality of spaced ridges extending about their peripheries. When the web is directed between the first and second rollers, the meshing of the ridges may form ribs into the web.

主权项

1. A method of producing a plastic bag comprising:
providing first and second cylindrical rollers, the rollers arranged parallel and adjacent to each other, the cylindrical surface of each roller having a plurality of circular ridges protruding radially outward, the plurality of circular ridges arranged parallel to and axially spaced apart from each other, the circular ridges of the first cylindrical roller being received between the spaced-apart circular ridges of the second cylindrical roller; providing a continuous web of flexible thermoplastic film material, the web having an initial width measured between a first side edge and a second side edges, the web having an initial average thickness substantially consistent across the initial width; folding the web about a fold line that is parallel to a machine direction; rotating the first and second cylindrical rollers in opposite rotational directions; advancing the web between the first and second rollers to incrementally stretch only a portion the initial width of the web in a direction that is perpendicular to the machine direction; and imparting a pattern of a plurality of parallel linear ribs to the stretch portion of the web, the pattern corresponding to the circular ridges of the first and second rollers.