Investigation into the Filter Efficiency of the Tobacco Rod in Cigarettes of Differing Density in Dependence on the Smoked Length/Untersuchung der Filterwirksamkeit des Tabakstranges bei Cigaretten verschiedener Härte in Abhängigkeit von der Abrauchlänge

With cigarettes of differing density the smoke condensate and nicotine yields in relation to the smoked length of the cigarette were determined. Seen generally, the amounts of these substances during the smoking of the first third are smaller in cigarettes with high density, about the same in the second third and only in the last third are they greater than in cigarettes with Iow density. The filter efficiency of the tobacco rod was determined by smoking equaI lengths of rod of the normaI and the shortened cigarettes. The coefficient of filtration was calculated. The coefficient of filtration µ is, for condensate, independent of the length of the filtering tobacco rod. This result is to be expected as the coefficient of filtration represents, by definition, the differential filtration performance. For the nicotine retention, on the other hand, a clear change in the coefficient of filtration is shown. The filtration power of the tobacco rod declines with decreasing Iength. The causes of this have not yet been investigated in detail. These results apply both to filter and plain cigarettes. The coefficient of filtration µ increases in the area investigated practically Iinearly with the density. The median coefficient of filtration for nicotine is nearly 60 % of the coefficient of filtration for condensate. A further investigation was conducted into the influence of the puff frequency on the condensate and nicotine amounts. With a constant puff number cigarettes were smoked with changed puff frequencies and the smoking values for smoke condensate and nicotine content were compared with each other (per cigarette and per puff).