| 摘要 |
A cigarette filter comprising longitudinally aligned core components a first of which is air-permeable and of relatively high pressure drop longitudinally of the filter but substantially air-impermeable radially of the filter and a second of which is air-permeable and of relatively low pressure drop longitudinally of the filter, and a common wrap or partial wrap which extends along and around or partially around said core components and provides for ventilation of the filter at a region longitudinally spaced from the first core component. |
