摘要 |
A filter for a cigarette includes a porous filter rod circumscribed by a smoke impervious wrapper wherein the filter rod with the non-porous wrapper therearound is provided with at least one groove therein extending a preselected distance longitudinally therealong. The groove is closed at one end and is provided with an opening substantially at the other end in flow communication with the filter rod. Tipping material circumscribes the wrapper and is provided with flow-through openings therein in flow communication with the groove wherein ventilating air is the only fluid flowing through the groove when the filter is used in combination with a cigarette during normal smoke draw. |