| 摘要 |
There is disclosed a method of operating on a cigarette, which comprises a tobacco rod and a filter element interattached by a thermoplastic tipping wrapper, to allow for the ingress of ventilation air. The filter element also comprises ventilation duct(s) extending therewithin. A heated former is brought into contact with the tipping wrapper in such a way as to form indentations which intersect with a ventilation duct(s) of the filter element and to seal upstream end portions thereof. |
