| 摘要 |
A method of flame-perforating a film, comprising the steps of:
- providing backing roll (14) having a support surface, wherein the support surface includes a plurality of lowered portions;
- providing a nip roll (20), wherein the nip roll (20) includes an outer surface, and wherein the outer surface of the nip roll is heated;
- providing a burner (36), wherein the burner (36) is positioned such that the angle measured between the burner (36) and the nip roll (20) is less than 45.degree., wherein a vertex of the angle is positioned at an axis of the backing roll;
- contacting a film (70) against the support surface;
- pressing the film (70) between the nip roll (20) and the support surface of the backing roll (14) to pre-heat the film (70); and
- thereafter perforating the film (70) with a flame of the burner (36). |
