| 摘要 |
A smoking article comprises a rod of smoking material, wrapped in a wrapper, in which rod the packing density of the smoking material varies continuously along at least a major portion of the overall length of the rod, but is constant across any section, within said portion, in a plane perpendicular to the longitudinal axis. The smoking material may be of homogeneous constitution throughout the rod. Preferably the density decreases continuously along the said portion of the rod in the direction away from the end of the rod to be lit, from which end the said portion may extend to substantially the other end of the rod. There may be between a 5% and a 40% weight difference between the more dense half of the length of the rod and the less dense half thereof. The density at the less dense end of the rod may be in the range of 170 to 240 mg cm-3 and that at the denser end in the range of 290 to 350 mg cm-3. |
