| 摘要 |
Disclosed is a method for forming a polymeric container blank having flexible fold lines which includes the steps of, among other steps, providing a sheet of polymeric material for use as a substrate for a container blank, providing a creasing tool which includes an applicator having a substantially flat lower surface that is spaced apart from a creasing rule and placing the polymeric material between the applicator and the creasing rule such that a first surface of the polymeric material is in contact with the lower surface of the applicator and a second surface of the material is in contact with the creasing rule. In this embodiment, the inventive method further includes the step of resonating the applicator of the creasing tool at an ultrasonic frequency so as to apply ultrasonic energy to the polymeric material and form at least one flexible fold line therein. |
