JP7418467B2 - smoking goods - Google Patents

Description

The present invention relates to smoking articles and methods of manufacturing smoking articles.

Cigarettes and other combustible smoking articles produce smoke that is inhaled by the user. Tobacco may be wrapped in paper to form a tobacco rod and a filter connected to the tobacco rod. The filter may be configured to modify the characteristics of the smoke produced by the smoking article, for example by adding flavor to the smoke produced by the smoking article.

In an embodiment of the first aspect of the invention there is provided a smoking article comprising tobacco material wrapped in a paper wrapper to form a tobacco rod, the paper wrapper having a It has a diffusivity of less than 15 CU and an air permeability of less than 15 CU.

The paper wrapper may have a diffusivity of about 0.1 cm/s to 0.3 cm/s.

The paper wrapper may have a diffusivity of about 0.15 to about 0.25, about 0.15 to about 0.20, or about 0.17 to about 0.22 cm/s.

The paper wrapper may have an air permeability of less than about 15 CU over at least 50% of the surface area of the paper wrapper.

The paper wrapper may have an air permeability of about 4 to about 12 CU.

The paper wrapper may have an air permeability of about 4 to about 12 CU over at least 90% of the surface area of the paper wrapper.

The paper wrapper may have an air permeability of less than about 10 CU or from about 3 to less than about 7 CU over at least 90% of the surface area of the paper wrapper.

The smoking article may include a filter.

The pressure drop across the filter may be about 40 mm WG to 180 mm WG.

The filter may include a ventilation area.

The ventilation area may provide 40% to 90% ventilation.

The filter may include filter material having a denier per filament of 2.5 to 9.

The filter may include filter material having a total denier of 10,000 to 32,000.

The paper wrapper may have a basis weight of 24-36 g/m ² .

The paper wrapper may have a basis weight of 27-32 g/m ² .

The paper wrapper may have a basis weight of about 28 g/m ² .

The paper wrapper may have a basis weight of about 32 g/m ² .

The paper wrapper may contain less than 30% filler by weight of the paper wrapper.

The paper wrapper may contain 15-25% filler by weight.

The filler may include calcium carbonate.

The paper wrapper may have an opacity of 60% to 80% or 68% to 80%.

The paper wrapper may contain less than 4% combustion additive by weight of the paper wrapper.

The paper wrapper may include about 1% combustion additive by weight.

The combustion additive may be sodium citrate, potassium citrate or a mixture of sodium and potassium citrate.

In an embodiment of the second aspect of the invention there is provided a method of making a smoking article, the method comprising: a paper wrapper having a diffusivity of about 0.1 cm/s to 0.5 cm/s and an air permeability of less than about 15 CU; forming a tobacco rod by wrapping tobacco material in a container.

The method of the invention may further include attaching a filter to the tobacco rod.

The method of the invention may further include providing a ventilation area to allow ventilation within the filter.

The paper wrapper may have a diffusivity of about 0.1 cm/s to 0.3 cm/s.

The paper wrapper may have an air permeability of about 4 to about 12 CU over at least 50% of the wrapper's surface area.

The paper wrapper may have an air permeability of about 4 to about 12 CU over at least 90% of the surface area of the wrapper.

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: FIG.

1 illustrates a smoking article according to certain embodiments. Figure 3 shows a smoking article according to another embodiment having a filter containing a capsule. Figure 3 shows a smoking article according to another embodiment having a filter that includes a tubular member. Figure 3 shows a smoking article according to another embodiment having a filter including a tubular member and an adsorbent dispersed within the filter material.

As used herein, the term "smoking article" refers to cigarettes, cigarillos, cigars and hand-rolled cigarettes (based on tobacco, tobacco derivatives, expanded tobacco, reconstituted tobacco, tobacco substitutes or other smoking materials). combustible smoking articles and their parts, including

The filters described herein may be provided to the user as an integral part of the smoking article or as a separate member separate from the smoking article. If provided separately, the filter unit and smoking article may be packaged separately or together as a kit of parts.

Smoking articles such as cigarettes and their formats can be categorized as "regular" (usually within the range of 68 to 75 mm, e.g. about 68 mm to about 72 mm), "short" or "mini" (less than 68 mm), "king size" (usually , 75-91 mm, e.g. 79 mm to about 88 mm), "long" or "super king" (usually in the range 91-105 mm, e.g. Cigarettes may be named according to their length, such as (within the range of approximately 121 mm).

In addition, "Regular" (approx. 23-25mm), "Wide" (more than 25mm), "Slim" (approx. 22-23mm), "Demi Slim" (approx. 19-22mm), "Super Slim" (approx. 16-19mm) and Cigarettes are also named by their circumference, such as "micro slim" (less than about 16 mm). Thus, a king size, super slim format cigarette, for example, has a length of about 83 mm and a circumference of about 17 mm. Regular king size format cigarettes have a circumference of 23 to 25 mm and an overall length of 75 to 91 mm.

Each format is manufactured with different length filters, with smaller filters usually being used for shorter, smaller circumference formats. Typically, the length of the filter will be approximately 15 mm when used in short regular formats and 30 mm when used in ultra long super slim formats. The tipping paper has a length longer than the filter, for example 3 to 10 mm, such that the tipping paper covers the filter and overlaps the tobacco rod to connect the filter to the tobacco rod.

The smoking articles and filters described herein can be made in any of the above formats, but are not limited to these formats.

The filter material forming the filters described herein may include cellulose acetate fiber tow. Filter materials include polyvinyl alcohol (PVOH), polylactic acid (PLA), polcaprolactone (PCL), poly(1,4-butanediol succinate) (PBS), and poly(butylene adipate-co-terephthalate) (PBAT). , starch-based materials, paper, cotton, aliphatic polyester materials and polysaccharide polymers or combinations thereof. The filter material may be plasticized with a plasticizer suitable for the filter material, such as triacetin, if the filter material is cellulose acetate tow, or may be unplasticized. The tow used to make filter units or other filter components may include fibers of "Y" shaped or other cross-section, 2.5 to 15 denier per filament, such as 3.0 to 9.0 denier per filament. Any suitable specification may be used, such as a denier value of 10,000 to 50,000, such as a total denier value of 15,000 to 45,000.

As used herein, the terms "flavour" and "flavoring agent" refer to materials that are permitted by local regulations and can be used to add tastes or aromas desired by adult consumers to products. Point. Such materials include extracts (e.g., licorice, hydrangea, magnolia leaves, chamomile, fenugreek, cloves, menthol, Japanese peppermint, aniseed, cinnamon, herbs, red koji, cherries, berries, peaches, apples, drambuie, bourbon, Scotch, whiskey, spearmint, peppermint, lavender, cardamom, celery, cascarilla, nutmeg, sandalwood, bergamot, geranium, honey extract, rose oil, vanilla, lemon oil, orange oil, cassia, caraway, cognac, jasmine, ylang-ylang, sage, fennel, pimento, ginger, anise, coriander, coffee, peppermint oil from any species of the Mentha genus), seasonings, bitter receptor site blockers, sensory receptor site activators or stimulants, sugars and/or sugar substitutes (e.g., sucralose, acesulfame potassium, aspartame, saccharin, cyclamate, lactose, sucrose, glucose, fructose, sorbitol, mannitol, etc.), charcoal, chlorophyll, minerals, vegetable breath deodorants, etc. Other additives may be mentioned. These materials may be imitations, synthetic or natural ingredients, or blends thereof. These materials may be in any suitable form, such as oils, liquids, powders, etc.

The same reference numerals are used herein to refer to equivalent features, articles or elements in the drawings.

FIG. 1 is a side sectional view of a smoking article 1. FIG. A smoking article 1, in this example a cigarette, has a mouth end 1a arranged to be placed in the user's mouth during smoking, and a lighting end 1b arranged to be ignited during smoking. Tobacco material 2 is wrapped in a paper wrapper 3 to form a tobacco rod.

In some instances, smoking articles do not include filters. In another example the filter 4 is connected to the tobacco rod by a tipping paper 5. The filter 4 is wrapped in a plug wrapper 6. A ventilation area 7 is provided such that outside air enters the filter 4 during use. The ventilation area may be provided as a series of perforations through the tipping paper 5 and the plug wrapper 6 into the filter 4.

The paper wrapper 3 has a diffusivity of approximately 0.1 cm/s to 0.5 cm/s. In some examples, paper wrapper 3 has a diffusivity of about 0.1 cm/s to about 0.3 cm/s.

In some instances, paper wrapper 3 has a diffusivity of less than about 0.30 cm/s. In some examples the paper wrapper 3 has a diffusivity of less than 0.25 cm/s. In some examples the paper wrapper 3 has a diffusivity of 0.15-0.2 cm/s. Such levels of diffusivity are advantageous as they have been found to be particularly effective in providing smoking articles such as cigarettes with a more constant delivery volume and higher number of puffs per puff. Such smoking articles have also been found to pass low flame spread tests known in the art and exhibit acceptable free air self-extinguishing rates. Free air self-extinguishing is the property of a smoking article that self-extinguishes when held in free air (ie, rather than placed on a substrate), which is undesirable from a consumer perspective. In some instances, the paper wrapper has a diffusion rate of have a rate.

The paper wrapper 3 has a low air permeability, in this example having an air permeability of less than about 15 Coresta units (CU). For example, the paper wrapper may have an air permeability of about 15 CU over at least 50% of the surface area or at least 75% or 90% of the surface area of the paper wrapper.

In some examples, paper wrapper 3 has an air permeability of about 4 to about 12 CU. In some examples, paper wrapper 3 has an air permeability of about 4 to about 12 CU over at least 90% of its surface area.

In some instances, the paper wrapper 3 has an air permeability of less than 10 Coresta units (CU) or from about 3 to about 7 CU over at least 50% or more preferably 75% or 90% of the surface area of the paper wrapper in each case. have

The paper wrapper 3 having the above-described low diffusivity and low air permeability ranges when used in the smoking articles described herein provides a smoking article with a paper having a high level of diffusivity and low air permeability when the smoking article is smoked. Reduces the amount of oxygen drawn into the tobacco rod compared to the tobacco rod. Reducing the amount of oxygen drawn into the tobacco rod has the effect of causing the tobacco 2 to burn more slowly between puffs, thus increasing the time that the tobacco rod burns, providing a longer smoking experience.

In some instances, the entire paper wrapper 3 has a low diffusivity and low air permeability range as described herein.

In some examples, the diffusion rate of the paper wrapper 3 may be uniform along the length of the tobacco rod when the paper wrapper 3 is wrapped around the tobacco rod. Additionally or alternatively, the diffusion rate of the paper wrapper 3 may be uniform over the circumference of the tobacco rod. The paper wrapper 3 may have a high or low diffusivity in some regions. In some examples, at least 50% of the paper wrapper may be provided with a low diffusivity, such as 0.3 cm/s or less. In some examples, more than 75%, or more than 80%, or about 100% of the wrapper may be provided with a low diffusivity, such as less than or equal to 0.3 cm/s or less than or equal to 0.25 cm/s. Alternatively or additionally, at least 50% of the paper wrapper may be provided with a low air permeability, for example 15 CU or less. In some examples, more than 80%, more than 90%, or about 100% of the wrapper is provided with a low air permeability as described above, such as 15 CU or less. The paper wrapper may have one or more discrete regions with low air permeability and low diffusivity. In some instances, the entire paper wrapper is provided with a uniformly low diffusivity and low air permeability within the ranges described herein. Providing low diffusivity and low air permeability throughout the paper wrapper reduces the free atmosphere of the smoking article for the duration of smoking compared to providing low diffusivity and low permeability in two or more discrete areas of the smoking article. Reduce the variability of self-extinguishing properties.

Filter 4 may be substantially cylindrical. The filter 4 may have a length of 6 mm to 30 mm, for example 7 mm to 20 mm. In one example, the length of the filter 4 is 18 mm.

The tobacco rod may also be substantially cylindrical, with an outer diameter substantially equal to the outer diameter of the filter 4, if a filter is provided. The tobacco rod includes a substantially cylindrical core of compacted tobacco material wrapped in a paper wrapper 3. The tobacco material 2 may include a blend of chopped tobacco and may also include recycled tobacco material. The paper wrapper 3 extends around the circumference of the tobacco rod and along its length, forming a wrapped tobacco rod. The end face of the tobacco rod remains open to allow gas flow to pass axially through the rod.

In some embodiments, the tobacco rod includes tobacco having a net weight based on the size and type of smoking article. For example, the tobacco weight may be a standard weight corresponding to a conventional smoking article of the same size. In some embodiments, the tobacco weight may be less than a conventional smoking article of the same size. Tobacco weight may be selected based on the desired characteristics of the smoking article. Lower tobacco weight is associated with reduced fouling of the paper wrapper. Furthermore, lower tobacco weight is associated with reduced CO and tar levels. However, low tobacco weight is also associated with reduced puff number. Consequently, the tobacco weight may be selected according to the characteristics of the smoking article to be achieved.

In some examples, the smoking article may be a smoking article that is 90 mm long and 21 mm in circumference. The net tobacco weight may be, for example, 510 mg. In other examples, the smoking article may have a tobacco weight as low as 480 mg. A smoking article with a lower tobacco weight of 480 mg contains less CO and tar, resulting in less staining of the paper wrapper. However, a smoking article with a lower tobacco weight of 480 mg will have fewer puffs when smoked by a user compared to an equivalent smoking article with a net tobacco weight of 480 mg.

In another example, a smoking article having a length of about 90 mm and a circumference of about 21 mm may contain a tobacco weight of 490 mg. Alternatively, the smoking article may contain a tobacco weight as low as about 460 mg.

In another example, a smoking article that is about 90 mm in length and about 23 mm in circumference may contain a tobacco weight of about 630 mg. Alternatively, the smoking article may contain a tobacco weight as low as about 560 mg.

It will be obvious to those skilled in the art that the tobacco weight can be increased, for example by choosing a lower tobacco weight to reduce staining, reduce CO and tar, or to increase the number of puffs that can be obtained when smoking. The selection may be based on these properties of the smoking article obtained by selecting the tobacco weight.

In use, when the smoking article 1 is smoked by a user, air is drawn through the lighting tobacco rod to provide smoke to the user. In embodiments that include a filter, the smoke is also drawn through the filter to remove some particulate matter from the smoke before it is provided to the user. In embodiments that include a ventilated filter, air during use is drawn through the ventilation area 7 of the filter 4 to dilute the smoke delivered to the user through the filter 4.

In some examples, the ventilation area 7 includes perforations in the filter tipping paper 5 and the plug wrapper 6. In some examples, the ventilation area 7 includes an embossed area on the filter tipping paper 5 and/or the plug wrapper 6. Alternatively, at least one of the tipping paper 5 and the plug wrapper 6 can be provided as a porous material, for example with a porosity of more than 200 Coresta units, which allows air into the filter 4. The filter 4 may be ventilated by ventilation grooves formed using laser or electrostatic drilling techniques. The ventilation area 7 can be provided in any part of the filter 4, for example at least 12 mm from the mouth end 1a of the smoking article. In examples having multiple filter sections or segments, the ventilation area can be provided, for example, in the filter section or segment adjacent to the tobacco rod.

In some examples, the pressure drop across filter 4 is between 40 mmWG and 180 mmWG. The filter pressure drop may be selected depending on the desired characteristics of the product. In some examples, the pressure drop across the filter is between 70 mm WG and 180 mm WG. In some examples, the pressure drop across the filter is between 130 mmWG and 180 mmWG. In some examples, the pressure drop across the filter is between 140 mmWG and 180 mmWG. In some examples, the pressure drop across the filter is between 70 mmWG and 100 mmWG. In some examples, the pressure drop across the filter is between 85 mmWG and 100 mmWG.

In some instances the filter is not provided with a ventilation area. In other examples the filter is provided with a ventilation area. The ventilation area 7 of the filter 4 provides between 40% and 90% ventilation when the smoking article is smoked in use. The ventilation area provides for example 55% to 90% ventilation. In some instances, the ventilation area provides between 55% and 85% ventilation. In some instances, the ventilation area provides 60% to 75% ventilation. In some instances, the ventilation area provides 65% to 75% ventilation.

Varying the ventilation level and pressure drop of the filter may vary the levels of CO and tar provided to the user. The high ventilation level of the filter results in reduced tar and CO levels when using the low diffusivity and low air permeability cigarette paper described herein. High levels of ventilation increase the number of puffs when smoking. However, the filter's lower ventilation level reduces the tendency of the smoking article to self-extinguish into the atmosphere when smoked. Therefore, the ventilation level may be selected depending on these characteristics of the smoking article.

In some instances, the paper wrapper surrounding the tobacco rod has a basis weight of 24-36 g/m ² . The weight of the paper is one of the factors that affects the diffusivity of the paper. Increasing the weight per square meter of paper increases the diffusivity of the paper. Therefore, the basis weight of the paper is selected to be between 24 and 36 g/m ² in order to reduce the diffusivity of the wrapper. In some instances, the paper surrounding the tobacco rod has a basis weight of 27-32 g/m ² . In some instances, the paper surrounding the tobacco rod has a basis weight of about 28 g/m ² . In some instances, the paper surrounding the tobacco rod has a basis weight of about 32 g/m ² . Increasing the square meter weight of the paper wrapper 3 increases the opacity of the paper wrapper. Increasing the paper's basis weight by increasing the diffusion rate of the paper reduces the level of staining of the cigarette paper during smoking.

In some instances the paper may include fillers. In some instances, the filler content of the paper wrapper 3 is less than 30% by weight. In some instances, the filler content of the paper wrapper is 15-25% by weight. Filler content lower than this may reduce the diffusion performance of the paper wrapper and thus lead to increased LIP (Low Inflammation Spread) pass rates. Additionally, the use of low filler content increases the number of puffs obtained when the smoking article is smoked during use. The filler content of the paper wrapper may be greater than 15%. In some instances, the filler content of the paper wrapper may be 21-22% by weight. In some examples the filler is calcium carbonate. However, it will be appreciated that any other suitable filler may be used. It will be appreciated that the amount of filler used may be selected by one skilled in the art to achieve desired characteristics such as diffusivity, number of puffs, opacity, smoke production and LIP pass rate.

Paper opacity is affected by the particle size of the filler used. For example, the smaller the particle size, the higher the opacity. In some examples, the particle size may be between 0.3 μm and 2 μm. Opacity is also influenced by the structure of the filler. For example, if calcium carbonate is used as a filler, it may include, but is not limited to, calcite crystals, precipitated calcium carbonate or ground calcium carbonate.

In some instances the paper wrapper includes a combustion additive. In some instances, the paper wrapper includes less than 4% combustion additive by weight. Combustion additives reduce the tendency of a smoking article to self-extinguish in free air, ie when a user holds the article between puffs, for example. However, increasing the amount of combustion additive may reduce the LIP pass rate of the smoking article. In some instances, the paper wrapper includes 1% combustion additive by weight. In some examples the combustion additive is tripotassium citrate. In some examples the combustion additive is trisodium citrate. In some examples, the combustion additive includes trisodium citrate and tripotassium citrate. However, it will be appreciated that any suitable combustion additive may be used. The amount of combustion additive may be selected by one skilled in the art to obtain desired characteristics such as, but not limited to, smoke production and LIP pass rate.

In some examples, the filter includes filter material having a denier of about 2.5 to about 9, such as about 3 to about 8, per filament.

In some examples, the filter includes filter material having a total denier of about 10,000 to about 32,000, such as about 12,000 to about 30,000.

FIG. 2 shows a smoking article 1' according to another embodiment, which is similar to the smoking article 1 of FIG. 1 except that the filter 4 includes a capsule 8. In this example, the filter 4 is formed from a filter material, in this example cellulose acetate tow, treated with a plasticizer, in this example triacetin. The capsule 8 is spherical and has a diameter of 3.5 mm, but other shapes and sizes of capsules can be used, such as capsules having a diameter of about 3 mm, or from 0.5 mm to 6 mm or from 2 mm to 5 mm. can. The capsule 8 is embedded within the filter material of the filter 4 and is enclosed on all sides. Capsule 8 contains fluid additives that modify the characteristics of mainstream smoke passing through smoking article 11. Capsule 8 can be manufactured and inserted into filter 4 using existing methods and equipment. In this example, capsule 8 contains a menthol flavoring agent, but other fluid or particulate additives can also be contained within capsule 8. The capsule can be ruptured by the consumer by squeezing the filter, releasing the fluid additive into the filter material of the filter 4. The length of the filter 4 in FIG. 2 may be between 7 mm and 30 mm, for example between 7 mm and 20 mm. In one example, the length of the filter 4 is 18 mm.

Figure 3 shows a smoking article 1'' according to another embodiment, which is the same as the smoking article 1 of Figure 1 except that it has a filter section 4a similar to the filter 4 of Figure 1 coaxially connected to a tubular member 4b. be. The tubular member 4b is formed from fibrous filter material in this example. The fibrous filter material in this example is cellulose acetate tow plasticized with triacetin. A flow path extends longitudinally through the center of the tubular member 4b. The diameter of the channel extending through the center of the tubular member 4b may be between 1 mm and 6 mm, for example between 2 mm and 5 mm. Tubular member 4b may be an unwrapped member or may be wrapped in a plug wrapper (not shown). Filter section 4a may be unwrapped or may be wrapped in a plug wrapper (not shown) and a mating plug wrapper 10 may be used to connect tubular member 4b and filter section 4a. . The filter section 4a may have a length of 6 mm to 30 mm, such as 6 mm to 20 mm. In one example the length of the filter section 4a is 12 mm or 18 mm. The length of the hollow tubular member 4b may be between 6mm and 15mm, for example between 6mm and 12mm or in one example 7mm.

Figure 4 shows a smoking article 1''' according to another embodiment, which has a filter segment 4c comprising an adsorbent 9 dispersed within the filter material upstream of the filter section 4a. Other than that, it is the same as the smoking article 1'' in FIG. 3. A mating plug wrapper 10 may be used to connect tubular member 4b, filter section 4a and filter segment 4c. Although the adsorbent 9 is provided in this example in the form of activated carbon particles, other forms of adsorbent such as ion exchange resins can be used. The filter section 4c may have a length of 6 mm to 20 mm, such as 6 mm to 18 mm or in one example 12 mm.

In the method of manufacturing a smoking article, such as the smoking article described herein, in a first step the tobacco rod spreads the tobacco material at a diffusion rate of about 0.1 cm/s to 0.5 cm/s and an air permeability of less than about 15 CU. It is formed by wrapping it in a paper wrapper. The filter may be attached to the tobacco rod in a second step. A ventilation area may be provided in the third step to allow ventilation within the filter.

In some examples of the methods of the invention, the paper wrapper has a diffusivity of about 0.1 cm/s to 0.3 cm/s. In some examples, the paper wrapper has an air permeability of about 4 to about 12 CU over at least 50% of the wrapper's surface area. In some examples, the paper wrapper has an air permeability of about 4 to about 12 CU over at least 90% of the surface area of the wrapper.

Examples of smoking articles according to some embodiments are described below. Unless otherwise specified, smoking articles were tested according to ISO 3308:2000 with 35 ml puffs in 2 seconds every 60 seconds.

Example 1
An exemplary cigarette having a circumference of approximately 23.4 mm was made with the filter configuration shown in FIG. 4. The net tobacco weight of the tobacco rod was 560 mg/cigarette. The basis weight of the paper wrapper was 28 g/m ² . The amount of combustion additive was 1%. The total length of the filter was 34 mm, and it was connected to a tobacco rod with a length of 56 mm to obtain a cigarette with a total length of 90 mm. Tip ventilation was arranged to be approximately 68%. The pressure drop across the filter was approximately 100 mmWG. The number of puffs obtained using these parameters was 9.5 puffs delivering approximately 5 mg of tar.

Example 2
An exemplary cigarette having a circumference of approximately 23.4 mm was made with the filter configuration shown in FIG. 4. The net tobacco weight of the tobacco rod was 630 mg/cigarette. The basis weight of the paper wrapper was 28 g/m ² . The amount of combustion additive was 1%. The total length of the filter was 27 mm, and it was connected to a tobacco rod with a length of 63 mm to obtain a cigarette with a total length of 90 mm. Tip ventilation was arranged to be approximately 67%. The pressure drop across the filter was approximately 90 mmWG. The number of puffs obtained using these parameters was 11, delivering approximately 7 mg of tar.

Example 3
Exemplary cigarettes having a circumference of about 21 mm were made with the filter configuration shown in FIG. 4. The basis weight of the paper wrapper was 28 g/m ² . The amount of combustion additive was 1%. The total length of the filter was 27 mm, and it was connected to a tobacco rod with a length of 63 mm to obtain a cigarette with a total length of 90 mm. Tip ventilation was arranged to be approximately 72%. The pressure drop across the filter was approximately 177 mmWG. The number of puffs obtained using these parameters was 10.3 puffs delivering approximately 6.1 mg of tar.

The various embodiments described herein are provided merely as an aid to understanding and teaching the claimed features. These embodiments are merely representative examples and are not exhaustive or exclusive. It is to be understood that the advantages, embodiments, implementations, features, structures, and/or other aspects of this disclosure limit the disclosure as defined in the claims or equivalents of the claims. It should not be considered as limiting, and that other embodiments may be utilized or modified without departing from the scope and/or spirit of the disclosure. The various embodiments may suitably comprise, consist of, or consist essentially of the disclosed elements, components, features, parts, steps, means, and other combinations. This disclosure also includes other inventions that are not currently claimed but may be claimed in the future.

Claims (26)

comprising tobacco material wrapped in a paper wrapper to form a tobacco rod;
The paper wrapper has a diffusivity of about 0.1 cm/s to 0.5 cm/s and an air permeability of about 4 to about 12 CU over at least 50% of the paper wrapper's surface area; A smoking article that is uniform along the length of the smoking article. The smoking article of claim 1, wherein the paper wrapper has a diffusivity of about 0.1 cm/s to 0.3 cm/s. or claim 1, wherein the paper wrapper has a diffusivity of about 0.15 to about 0.25, about 0.15 to about 0.20, or about 0.17 to about 0.22 cm/s. Smoking article described in 2. 4. The smoking article of any preceding claim, wherein the paper wrapper has an air permeability of about 4 to about 12 CU over at least 90% of the surface area of the paper wrapper. 5. A smoking article according to any preceding claim, further comprising a filter. 6. The smoking article of claim 5, wherein the pressure drop across the filter is about 40 mm WG to 180 mm WG. 7. A smoking article according to claim 5 or 6, characterized in that the filter includes a ventilation area. Smoking article according to claim 7, characterized in that the ventilation area provides between 40% and 90% ventilation. A smoking article according to any one of claims 5 to 8, characterized in that the filter comprises a filter material having a denier per filament of 2.5 to 9. A smoking article according to any one of claims 5 to 9, characterized in that the filter comprises filter material having a total denier of 10,000 to 32,000. Smoking article according to any one of claims 1 to 10, characterized in that the paper wrapper has a basis weight of 24 to 36 g/m ² . Smoking article according to claim 11, characterized in that the paper wrapper has a basis weight of 27 to 32 g/m ² . 13. The smoking article of claim 12, wherein the paper wrapper has a basis weight of about 28 g/ ^m2 . 13. The smoking article of claim 12, wherein the paper wrapper has a basis weight of about 32 g/ ^m2 . 15. A smoking article according to any preceding claim, wherein the paper wrapper comprises less than 30% filler by weight of the paper wrapper. 16. The smoking article of claim 15, wherein the paper wrapper contains 15-25% filler by weight of the paper wrapper. 17. A smoking article according to claim 15 or 16, characterized in that the filler comprises calcium carbonate. A smoking article according to any one of the preceding claims, characterized in that the paper wrapper has an opacity of 60% to 80% or 68% to 80%. 19. A smoking article according to any preceding claim, wherein the paper wrapper comprises less than 4% of a combustion additive by weight of the paper wrapper. 20. The smoking article of claim 19, wherein the paper wrapper includes about 1% by weight of a combustion additive. 21. A smoking article according to claim 19 or 20, characterized in that the combustion additive is sodium citrate, potassium citrate or a mixture of sodium and potassium citrate. Forming tobacco rods by wrapping tobacco material in a paper wrapper having a diffusion rate of about 0.1 cm/s to 0.5 cm/s and an air permeability of about 4 to about 12 CU over at least 50% of the surface area of the paper wrapper. 1. A method of manufacturing a smoking article, wherein the diffusion rate of the paper wrapper is uniform along the smoking article . 23. The method of manufacturing a smoking article according to claim 22, further comprising attaching a filter to the tobacco rod. 24. The method of manufacturing a smoking article according to claim 23, further comprising providing a ventilation area to allow ventilation within the filter. 25. The method of manufacturing a smoking article according to any one of claims 22 to 24, wherein the paper wrapper has a diffusion rate of about 0.1 cm/s to 0.3 cm/s. 26. A method of manufacturing a smoking article according to any one of claims 22 to 25, wherein the paper wrapper has an air permeability of about 4 to about 12 CU over at least 90% of the surface area of the paper wrapper.

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