摘要 |
A cigarette filter includes a porous filter element attached to a cigarette, the element circumscribed by ventilating air ducts with an impermeable barrier therebetween so that smoke travels down the filter element and ventilating air travels down the ducts during use. The size of the ducts, the number of ducts, and the flow rate of ventilating air is so defined that substantially all of the smoke is dispersed immediately upon exiting the filter element.
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