Popular smoking articles, such as cigarettes, have a substantially cylindrical rod shaped structure and include a charge, roll, or column of smokable material such as shredded tobacco (e.g., in cut filler form) surrounded by a paper wrapper thereby forming a so-called “smokable rod” or “tobacco rod.” Normally, a cigarette has a cylindrical filter element aligned in an end-to-end relationship with the tobacco rod. Typically, a filter element comprises cellulose acetate tow plasticized using triacetin, and the tow is circumscribed by a paper material known as “plug wrap.” A cigarette can incorporate a filter element having multiple segments. Typically, the filter element is attached to one end of the tobacco rod using a circumscribing wrapping material known as “tipping paper,” in order to provide a so-called “filtered cigarette.” It also has become desirable to perforate the tipping material and plug wrap, in order to provide dilution of drawn mainstream smoke with ambient air. Descriptions of cigarettes and the various components thereof are set forth Tobacco Production, Chemistry and Technology, Davis et al. (Eds.) (1999).
Normally, a generally cylindrical or rod-shaped smoking article, such as a cigarette, has a generally circular cross-sectional shape, and each of the lighting tip and mouth end faces thereof extend virtually perpendicular to the longitudinal axis of that cigarette. A cigarette typically is employed by a smoker by lighting one end thereof and burning the tobacco rod. The smoker then receives mainstream aerosol (e.g., smoke) into his/her mouth by drawing on the opposite end (e.g., the filter or mouth end) of the cigarette.
Similarly several different configurations are known for cigarette lighters. One common example uses a fuel such as liquid butane, a controlled stream of which changes to a gas phase upon being released from a pressurized container and is ignited by an electric spark or flint generated spark to sustain a flame. Another common example uses liquid naphtha which is transported through a wick in a lighter to a site for ignition by an electric spark or flint generated spark to sustain a flame. Still another common example is an electric lighter, which typically has a coil or other shape of a wire with high resistance, which—when electric current is passed therethrough—gets sufficiently hot to ignite a cigarette. With each of these three lighter configurations, a user/smoker facilitates lighting by drawing mainstream aerosol though the cigarette into his/her mouth while applying a flame or heated lighter surface to the lighting end of the cigarette for a time sufficient to establish self-sustaining flame. This is commonly referred to as “lighting puff.”
With regard to smoking articles such as cigarettes, certain attempts have been made to alter the nature or character of smoke generated by cigarettes through the positioning of various components or component materials near the lighting ends or tip portions of cigarettes. In one regard, a cigarette having a paper wrapped tobacco rod may include ingredients (e.g., ammonium salts or tobaccos having relatively high ammonia levels) located at its tip portion that corresponds to its lighting end. See, for example, U.S. Pat. No. 6,874,508 to Shafer et al. and U.S. Pat. App. Pub. No. 2005/0022829 to Atwell et al., which are incorporated herein by reference. Likewise, attempts have been made to alter the nature or character of smoke by positioning components near the mouth end of cigarettes. See, for example, U.S. Pat. No. 3,494,366 to Starbuck et al., entitled, “Cigarette Having Heat Sink Means For Removing Impurities From Cigarette Smoke.” In another smoking article, the geometric configuration of the lighting end may be modified from the traditional flat-faced cylinder (see, e.g., U.S. patent application Ser. No. 11/868,264, to Borschke, et al.).
In yet another regard, certain types of cigarettes, such as those marketed commercially under the brand names “Premier” and “Eclipse” by R.J. Reynolds Tobacco Company, have incorporated combustible fuel sources (e.g., carbonaceous fuel elements) that generate heat for the production of a smoke-like aerosol. See, for example, the types of smoking articles set forth in U.S. Pat. No. 4,793,365 to Sensabaugh et al.; U.S. Pat. No. 5,183,062 to Clearman et al.; and U.S. Pat. No. 5,551,451 to Riggs et al.; and U.S. Patent Application Publication Nos. 2007/0023056 to Cantrell et al.; 2007/0215167 to Crooks et al.; and 2007/0215168 to Banerjee et al.; each of which is incorporated herein by reference.
The concentration of mainstream aerosol constituents changes on a puff-by-puff basis starting with the lighting puff and progressing down the rod. It would be desirable to provide a manner or method for providing alteration of the overall composition of mainstream aerosol generated by a cigarette, particularly in the first puffs. In particular, it may be desirable to selectively reduce a user's contact (e.g., by inhalation or ingestion) with certain compounds that are known to occur at higher concentrations in the first puff or two upon lighting a smoking article.