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Air Dilution and Factors that Atiect it Air Dilution and 'Tar' The objectives for this portion of the training program are to answer several questions about air dilution and 'tar'. The questions are: *What is 'tar' ? "How can we change 'tar' ? "'What is air dilution ? *Why is it important to control air dilution ? The discussion that follows should answer each ot these questions and show the importance of the parts that go into a cigarette. I. 'Tar' and Nicotine Consumers buy the cigarettes that we make, but the cigarette is not the end product. Consumers want the taste and satisfaction that comes from smoking cigarettes. If smoke is the major quality of a cig- arette, we need a way to measure that quality. The tobacco industry has a way to measure how much smoke a cigarette delivers. The name given to the measure is 'tar'. Over the years, the cigarette 'tar' ranking has gained great importance to tobacco companies. These 'tar' rankings are used to market cigarettes. That is, low-'tar' cigarettes are made for groups of customers who want low-'tar'. Other groups of consumers want higher-'tar' products. Since 'tar' ratings are advertized, consumers use the numbers to compare products and styles. Finally, the 'tar' rankings are used to note changes in a product. Measurement of 'tar' delivery is very important when new or improved products are developed. Since the 'tar' number is a measure of how much smoke a cigar- , ette delivers, it is interesting to discuss some details about smoke. Smoke is an "aerosol". That is, smoke is made up of billions of very tiny droplets, suspended in a gas. Each of the droplets in cigarette smoke contains many thousands of different chemicals. The gas in which the droplets are suspended is mostly air. But, hundreds of other chemicals are mixed with the air. The droplets, called "smoke solids" or "particulates", are the visible part of the smoke. These smoke solids are collected and measured in a special way to get the 'tar' ranking for a cigarette. 'Tar' is the name given to the "particulate" part of cigarette smoke collected and measured in a special way. A cigarette doesn't "contain" 'tar'. Cigarettes must be smoked and the smoke collected to measure the 'tar'. A very specialized method has been developed to smoke cigarettes for 'tar' measurements. Since the Federal Trade Commission regularly monitors 'tar' deliveries of cigarettes, the measurement has been called "FTC 'tar "'. The measurement includes specif ications for the size of a puff, the length of time a puff lasts and how often puff s are taken while the cigarettes are being smoked. In the FTC 'tar' test, cigarettes are smoked by taking a 35 milliliter puff lasting 2 seconds, once every minute. The exact way the smoke particulates are collected is also specified. Changes to any of the

smoking test specifications will change the 'tar' delivery of a cigarette. For example, larger putf s or puffing more often will increase the 'tar'. Thus, the many specifications are needed so that different laboratories will use the same method and get similar results for similar cigarettes. One of the many chemicals in the particulate part of smoke is nicotine. Nicotine is partly responsible ior the taste sensation of cigarette smoke. Tobacco contains nicotine. When the tobacco is burned, some of the nicotine is mixed in the smoke droplets and delivered to the smoker. The amount of nicotine delivered in the smoke is measured by the FTC method when 'tar' is measured. In summary, cigarette smoke is the important quality to our cust- omers. Even though smoke is very complicated, measures of how much smoke cigarettes deliver can be made. 'Tar' is the name for the par- ticulates of smoke measured in a special way. Nicotine is delivered from the tobacco into the particulate part of the smoke. The 'tar' and nicotine ratings are important in advertizing and marketing and in development of new brands. II. Cigarette Design Components 13ecause cigarettes must be made in different styles and with dif - ferent smoke deliveries to satisf y the needs of our customers, we need ways to design different products. To "design-in" a certain 'tar and nicotine delivery, several cigarette components may be adjusted. The main components used to adjust the smoke delivery are the f ilter, the air dilution and the tobacco rod of the cigarette. The filter is a bundle of fibers or "plug" attached to the end of the tobacco rod. The f ilter plug contains several thousand f ibers or "filaments". Before processing into filters, the fiber material is called "tow". Different filters are specif ied by the "tow item", which relates to the size and number of f ibers needed in the filter. As smoke is drawn through a cigarette, some of the smoke droplets hit the f ibers in the f ilter and become trapped. The trapped smoke particles do not pass through the f ilter and are not collected in the 'tar' measurement. Filter specifications can be adjusted so that more or less smoke particles are trapped, giving more or less 'tar' deli- very. The size and the number of f ibers in the filter can be changed to vary the amount of smoke that will pass through the f ilter and are specified in the tow item. The length and diameter of the f ilter also change the amount of smoke that will pass through. Air dilution is a controlled "leak" in the f ilter-end of the cigarette. As a puff is taken on the cigarette, part of the puff enters through the leak in the f ilter. The remaining part of the puff is drawn past the burning end of the cigarette. In this way, the amount of air dilution determines how much smoke will be drawn into the cigarette. Higher levels of air dilution decrease the amount of 'tar' delivered by the cigarette. Air dilution, unlike the filter, is not a component part of a cigarette. The amount of air dilution is the end product of the materials that go into the cigarette. The plug wrap and tipping ..+ Z: JV_ ~ papers must allow air to pass through them to get air dilution in w ~

the filter. The amount of air passage through these papers must be carefully specified to get the air dilution needed so that a cig- arette delivers the right 'tar' and nicotine. The tobacco rod can be adjusted to change the amounts of 'tar' and nicotine delivered. The length or diameter of the tobacco por- tion can be changed. Less tobacco burned will cause less smoke to be delivered by a cigarette. Changes in the tobacco blend can change the nicotine delivery. Different kinds of tobacco contain different amounts of nicotine. Often, blends are changed slightly so that the tobacco used in a product contains the same amount of nicotine from year to year. Compared with filters and air dilution, the changes in smoke delivery that can be made with the tobacco rod are small. In summary, there are three main ways to adjust the 'tar' delivery of cigarettes. Filters are made of f ibers that trap smoke particles. Different f ilters can be specif ied to change 'tar' deliveries. Air dilution is a "leak" in the filter. With air dilution, part of a puff enters the filter leak, while the rest of the puff "makes" smoke at the burning end of the cigarette. Increased air dilution decreases the 'tar' delivery. Air dilution is adjusted by changing plug wrap or tipping paper. Small changes in 'tar' and nicotine deliveries can be made by changes to the amount or types of tobacco used in a cigarette. Ill. Air Dilution Components and Control Air dilution is especially important for "low-'tar "' and "ultra low-'tar "' cigarettes. Filters and tobacco rod adjustments alone can- not be used to get the low-'tar' products our customers want. All low-'tar' cigarettes must use high amounts of air dilution. Since 'tar' depends on air dilution, the amount of air dilution must be controlled to get consistent smoke deliveries for the customer. Two component parts of the cigarette are used to change the amount of air dilution. These parts are the plug wrap and the tipping paper. Since air dilution is a controlled "leak" in the f ilter, both plug wrap and tipping must allow air to pass through them in some way. A new way of obtaining dilution has recently arrived at RJR. This is the on-line LASER process. With this method, plugwrap and tipping papers are perforated after making the cigarette. Four plug wrap papers are used at RJR. These are identified by the reference numbers 626, 70-M1, 260-Mi and 646. The main difference between these papers is the amount of air that will pass through them in a CORESTA test. The amount of air that can be passed through a paper is called the "porosity" or "permeability". The more air that can be passed through the plug wrap, the higher the amount of air dilution in the f inished cigarette. The 626,plug wrap has a low porosity or ability to pass air. It is used for higher-'tar' cigar- ettes. The 70-M1 has moderate porosity and 260-M1 has high porosity. These plug wraps are used for low- and ultra low-'tar' products. The 646 plug wrap has little ability to pass air. This plug wrap is used only for cigarettes that require no air dilution. Tipping is the other component needed to get air dilution. At RJR, we buy tipping paper that has been perforated to our specif i- cations for each brand. The perforations.or holes will allow air to

pass through the tipping. The amount of air that will pass through the pertorated tipping is measured in a CORESTA test like the one used for plug wraps. The size and number of the holes in the tipping determine the "porosity" or the amount of air that will pass through the tipping. The higher the porosity of the tipping, the higher the amount of air dilution in the cigarette. Tipping is perforated mechanically, electrically or with a LASER. Electrically perforated papers have hundreds of tiny holes. The perforations are barely visible on a completed cigarette. This type of tipping is used on higher 'tar' cigarettes where low air dilution is needed. LASER and mechanically perforated tippings have fewer and larger holes than the electrically perforated paper. These perforations can be easily seen on the finished cigarette. LASER perforated tipping usually has one row of holes. Mechanically perforated tipping can have 1,2,3 or more rows of holes. The porosity of the paper is adjusted by the number of rows and the size of the perforations. That is, more holes allow more air to pass through the tipping and more air dilution is obtained in a cigarette. LASER or mechanically perforated tippings are used on low- and ultra low-'tar' products. Porous tippings and plug wraps are used to design in a certain amount of air dilution. Other parts of the cigarette also affect the dilution, though. The "draft" qf the filter and the tobacco rod can change air dilution. "Draft" is the resistance to air passage through the filter or tobacco rod. Air will always flow through the path of lowest resistance. lf the draft of the f ilter or tobacco rod is increased, the air dilution path of air f low has a lower resistance. The amount of air dilution is then increased. Cigarette designers account for the draft f actor when materials are specified for a product. However, large changes in these drafts can change air dilution even if the plug wrap and tipping materials are correct. To show the importance of materials on the amount of air dilution, consider a cigarette with a 5 mg 'tar' delivery. This cigarette is made with 70-MI plug wrap and tipping with 3 rows of perforations. The air dilution is 50 %. Suppose that an incorrect plug wrap were used on this product. The air dilution would be 0% if 646 were used, 34% for 626 and 72% for 260-Mi. These differences from the right dilution have a tremendous effect on the 'tar'. If the dilution were 0%, the 'tar' would jump to 15 mg. At 72% dilution, the 'tar' would be as low as 1 mg. lncorrect tipping also causes large air dilution and 'tar' differ- ences. If non-perforated tipping were used, 0% air dilution and 15 mg 'tar' would result. The air dilution would be 27% ii electrically perforated tipping were substituted. Using 1 row of perforations would give 32% dilution; 2 rows would give 42%. The tipping and plug wrap materials must have the correct porosity specifications to give the right air dilution and 'tar'. But, the materials are not the whole answer. Improper machine adjustments can have effects just like using the wrong material. Poor glue roller alignment can cause one or more rows of tipping holes to be glued shut. This has the same effect as using a tipping with less-than-specified porosity. The dilution decreases and 'tar' increases. Other adjustments have different etfects and are important.

To summarize, tipping and plug wrap papers are used to get a certain air dilution. These papers are specif ied by porosity; or, the amount of air that can be passed through them. The draft of the filter and tobacco rod can affect dilution but is not used to change it. Both plug wrap and tipping porosity changes have large effects on dilution. Air dilution has a large effect on 'tar'. In fact, a change in dilution of 5% can mean a 1mg 'tar' change. To get the consistency we need, the components must be correct and the machine adjustments must be accurately set.