| 摘要 |
The invention concerns a grid (3a) for continuously perforating a thermoplastic film being reeled off, using suction through the openings of a grid comprising openings (5) with an elliptical cross-section and having the same orientation. Preferably the ratio between the length (a) of the major axis and the length (b) of the minor axis of each elliptical opening ranges between 1.15 and 1.30, and more preferably between 1.18 and 1.20. The invention is useful for producing thermoplastic films with circular perforations, in particular for absorbent disposable hygienic articles. |
