| 摘要 |
1323947 Tobacco-smoke filter BRITISHAMERICAN TOBACCO CO Ltd 12 April 1972 [24 May 1971] 16472/71 Heading A2C The filter comprises a porous filter tube 1 extending eccentrically and substantially longitudinally within an outer tubular wrapper 2, spaces 8, 7 within the tube I and between it and the wrapper 2 being closed at opposite ends so that smoke entering the filter at one end is constrained to flow radially through the tube 1 from space 8 to space 7 before leaving the filter. The space 7 is closed at one end by a disc 3 having an opening 6 communicating with the space 8, and the space 8 is closed at one end by a disc 4 provided with longitudinal grooves 9 in its periphery communicating with the space 7. The tube 1 may be formed of filter paper, the wrapper 2 of cigarette paper or plastics material, and the discs 3, 4 of compressed paper, paper board, or smoke-impervious plastics material. A method of making the filter using conventional apparatus components is also disclosed. |
