ENDS

The present disclosure relates to a smoking article with a hydrophobic wrapper that exhibits a reduced tendency to shed small tobacco pieces (shorts) from the open end during transport, storage or handling.

Combustible smoking articles, such as cigarettes, typically comprise a cylindrical rod of tobacco cut filler surrounded by a paper wrapper and typically a cylindrical filter axially aligned in an abutting end-to-end relationship with the wrapped tobacco rod. The cylindrical filter typically comprises a filtration material circumscribed by a plug wrap. The wrapped tobacco rod and the filter are joined by a band of tipping wrapper, normally formed of a paper material that circumscribes the entire length of the filter and an adjacent portion of the wrapped tobacco rod. A cigarette is employed by a consumer by lighting one end thereof and burning the tobacco rod. The smoker then receives mainstream smoke into their mouth by drawing on the mouth end or filter end of the cigarette.

The tobacco filling of tobacco rods for smoking articles usually includes a blend of ingredients, each of which has a range of particle sizes. The blend normally contains a fraction of small particles known as shorts. During the packaging, transport, handling and storage of smoking articles, tobacco shorts can leak out of the open (unfiltered) end of the tobacco rod and accumulate in the pack holding a plurality of smoking articles and on the outer surfaces of the smoking article, thereby negatively impacting the aesthetic appeal and perceived cleanliness of the product.

Various methods have been utilized to prevent the problem of so-called "loose ends" in the manufacture of cigarettes. The term "loose ends" refers to leakage of the tobacco filling (not just shorts) from the open end of the tobacco rod. If an excessive amount of tobacco is lost, then the ends of some tobacco rods can end up inadequately filled, thereby, negatively impacting the appeal of the product.

In order to minimise "loose ends", it is known to arrange for the smoking article making machine to produce a smoking article with localised additional quantities of tobacco (so-called "dense ends") coinciding with the open end of the tobacco rod, so that the open end is at least initially more dense than the remainder of the tobacco rod. However, this dense end may still permit leakage of tobacco shorts. Paper caps have been utilized to seal the end of the tobacco rod to prevent loose tobacco from falling out of the tobacco rod. While effective, these caps add complexity and cost to the manufacturing process.

Adhesive material has been added to the tobacco filling to reduce or prevent loose tobacco from falling out of the tobacco rod open end. However, the adhesive material may cause weakening and spotting or discoloration of the tobacco rod, leading to rejection during the production process or by the consumer. This may be especially true in hot and humid environments.

It would be desirable to provide a tobacco rod that prevents tobacco filling from falling out of the end of the tobacco rod while maintaining the color and structural integrity of the tobacco rod. It would also be desirable that the tobacco rods not affect the taste of the smoke or aerosol generated by the smoking article.

According to a first aspect, a tobacco rod includes a paper wrapper defining a tobacco rod cavity with an open end and an open end region adjacent to the open end. The open end region of the paper wrapper is hydrophobic due to hydrophobic groups covalently bonded to the paper. Tobacco cut filler is disposed within the tobacco rod cavity. A binding agent is disposed on the tobacco cut filler at the open end.

The hydrophobic open end region may be formed by applying a liquid composition comprising a fatty acid halide to at least one surface of the hydrophobic tube region, maintaining the surface at a temperature of about 120°C to about 180°C, wherein the fatty acid halide reacts in situ with protogenic groups of material in the hydrophobic tube region resulting in the formation of fatty acid esters.

In another aspect, a method of forming a tobacco rod includes the step of (1) forming a tobacco rod comprising loose tobacco filling circumscribed by a paper wrapper with an open end, and an open end region adjacent to the open end, the open end region of the paper wrapper being hydrophobic due to hydrophobic groups covalently bonded to the paper; (2) applying a liquid composition to the loose tobacco filling at the open end, the liquid composition comprising a binding agent dissolved in water; and (3) removing at least a portion of the water from the liquid composition to form adhered tobacco filling at the open end.

Tobacco rods for smoking articles that have a hydrophobic end portion can allow for a simple method of applying an aqueous solution of a binding agent to the end portion of tobacco filling or tobacco rod adhering tobacco cut filler. The aqueous solution of a binding agent is not absorbed by the hydrophobic paper wrapper. The aqueous solution of a binding agent can be applied to a single tobacco rod or applied to a plurality of tobacco rods at the same time. The color and structural integrity of the tobacco rod is maintained even though an aqueous binding agent is applied to the open end region of the tobacco rod. The binding agent may not migrate through the paper wrapper to an adjacent paper wrapper.

The hydrophobic groups or the binding agent do not contribute to the sensory perception of the tobacco rod. The hydrophobic groups can be selectively formed at the open end region of the tobacco rod. Selective placement of the hydrophobic groups can reduce material costs and place the hydrophobic groups where they are most effective.

Smoking articles in accordance with the present disclosure may be cigarettes or other smoking articles in which tobacco material forming a tobacco substrate or tobacco rod is combusted to form mainstream smoke.

The term "smoking article" is used here to indicate cigarettes, cigars, cigarillos and other articles in which a smokeable material, such as a tobacco, forms a tobacco rod and is lit and combusted to produce smoke. Preferably a smoking article has a cylindrical shape defining a mouthpiece segment at a first end and the tobacco rod having an open end at the opposing end.

The term "tobacco filling" refers to shredded tobacco or tobacco cut filler, or it may include reconstituted tobacco or cast leaf tobacco, or a mixture of both.

The term "mainstream smoke" is used herein to indicate smoke produced by combustible smoking articles, such as cigarettes. Mainstream smoke flows through the smoking article and is consumed by the user.

The term "hydrophobic" refers to a surface exhibiting water repelling properties. One useful way to determine this is to measure the water contact angle. The "water contact angle" is the angle, conventionally measured through the liquid, where a liquid/vapour interface meets a solid surface. It quantifies the wettability of a solid surface by a liquid via the Young equation.

The term "mouthpiece" or "mouthpiece segment" is used herein to indicate the portion of the smoking article that is designed to be contacted with the mouth of the consumer. The mouthpiece can be the portion of the smoking article that can includes a filter, or in some cases the mouthpiece can be defined by the extent of the tipping paper, if present. In other cases, the mouthpiece can be defined as a portion of the smoking article extending about 40 mm from the mouth end of the smoking article, or extending about 30 mm from the mouth end of the smoking article or extending in a range from about 15 mm to about 60 mm.

The term "protogenic" refers to a group that is able to donate a hydrogen or a proton in a chemical reaction. Preferably, the protogenic groups are reactive hydrophilic groups such as but not limited to a hydroxyl group (-OH), an amine group (-NH2), or a sulfhydryl group (-SH2). The present disclosure provides a tobacco rod comprising a paper wrapper defining a tobacco rod cavity with an open end and an open end region adjacent to the open end. The open end region of the paper wrapper is hydrophobic due to hydrophobic groups covalently bonded to the paper, forming a hydrophobic end region. Loose tobacco filling or cut tobacco filler is disposed within the tobacco rod cavity and a binding agent disposed on the loose tobacco filling or cut tobacco filer at the open end region.

The tobacco rod may be axially aligned with a filter element to form a mouthpiece end of the smoking article. In some embodiments the smoking article may not include a filter element. In these embodiments, the loose tobacco filling or cut tobacco filer at both open ends of the tobacco rod may include the binding agent and the paper wrapper may be hydrophobic due to hydrophobic groups covalently bonded to the paper, forming a hydrophobic end regions.

The loose tobacco filling may comprise, consist essentially of, or consist of any of the blends of tobacco materials and other components conventionally used to fill cigarettes. Such blends normally contain both tobacco cut filler and tobacco shorts, suitably uniformly mixed. The term "shorts" herein refers to any tobacco particles filling the tobacco rod that pass a 2 mm sieve. T e term "cut filler" herein refers to any tobacco particles filling the tobacco rod that do not pass a 2 mm sieve. The shorts and cut filler may therefore each include particles of tobacco lamina, puffed tobacco lamina, tobacco stems or reconstituted tobacco, or any other ingredient of the tobacco blend. The tobacco filling may include at least about 5 wt% shorts, or at least 10 wt% shorts. The tobacco filling may include from about 5 wt% to about 50 wt% shorts, or from about 5 wt% to about 25 wt% shorts, or from about 10 wt% to about 25 wt% shorts.

The loose tobacco filling may comprise any suitable type or types of tobacco material or tobacco substitute, in any suitable form. Preferably, the tobacco includes flue-cured tobacco, Burley tobacco, Maryland tobacco, Oriental tobacco, specialty tobacco, homogenized or reconstituted tobacco, or any combination thereof. The term "loose tobacco filling" is used herein to indicate loose tobacco material that is predominately formed from the lamina portion of the tobacco leaf. The term "loose tobacco filling" is used herein to indicate both a single species of Nicotiana and two or more species of Nicotiana.

The escape of shorts or loose tobacco filling from the open end of the tobacco rod is inhibited by adhering the shorts and loose tobacco filling to together at the open end of the tobacco rod. The shorts and loose tobacco filling are adhered together with a binder material. This binder material is disposed on the loose tobacco filling at least at or only at the open end of the tobacco rod. The binder material may extend onto the loose tobacco filling for at least about 1 mm or at least about 2 mm or at least about 3 mm or at least about 4 mm or at least about 5 mm into the open end. The binder material can extend along the final about 15 mm, or final about 10 mm or final about 6 mm of the tobacco filling of the tobacco rod open end. The binder material can extend along the final about 25%, or final about 20% or final about 15% of the length of the tobacco rod (adjacent to the tobacco rod open end).

Only a portion of the tobacco cut filler or loose tobacco filling forming the tobacco rod may be adhered together with the binding agent or binder material. The binder material may extend onto the loose tobacco filling for only about 1 mm, or only about 2 mm, or only about 3 mm, or only about 4 mm, or only about 5 mm into the open end. The binder material can extend along only the final about 15 mm, or only the final about 10 mm, or only the final about 6 mm of the tobacco filling of the tobacco rod open end. The binder material can extend along only the final about 25% or less, or only the final about 20% or less, or only the final about 15% or less of the length of the tobacco rod (adjacent to the tobacco rod open end).

Adhesion of the shorts and loose tobacco filling or cut tobacco filler may be achieved simply by wetting the shorts with water so that they stick to the larger cut tobacco filler and then drying. Preferably, adhesion is accomplished by utilizing a binding agent (an adhesive, for example). The binding agent may be any binding agent that is approved for use in smoking products. Suitably, the binding agent is aqueous or dispersible in water, for example it is suitably soluble in water at 25°C in amounts of at least about 1mg/ml or at least about 10mg/ml.

The binding agent may be selected from the group consisting of saccharides, oligosaccharides, polysaccharides, or derivatives thereof. The binding agent may be selected from the group consisting of starches such as corn starch, tapioca starch, starch derivatives such as dextrin or hydroxypropyl starch, microcrystalline cellulose, cellulose derivatives such as hydroxypropylcellulose, hydroxypropyl-methylcellulose, hydroxyethylcellulose, carboxymethylcellulose (and salts thereof such as sodium carboxymethylcellulose), gums such as guar gum, locust bean gum, carrageenan, gum arabic, pectins or alginates, and mixtures thereof. The binding agent may or may not comprise a flavoring agent.

Preferably, the binding agent is selected from the group consisting of dextrins and polysaccharides and derivatives thereof. For example, gum arabic may be suitable since solutions of gum arabic in water have low viscosity making them suitable for penetration into the tobacco filling the open end of the tobacco rod. Preferably the binding agents may include polysaccharide salts, such as carboxymethylcellulose salts, such as ammonium salts for formaldehyde reduction.

The binding agent may include a plasticizer to increase the plasticity or flexibility of the binding agent disposed on or within the tobacco rod. The plasticizer may improve the compliancy of the binding agent disposed on or within the tobacco rod and provide a uniform hardness or at least a negligible difference in hardness along the length of the tobacco rod and between regions that include the binding agent and regions that are free of the binding agent. For example, an open end region of the tobacco rob that includes the this binding agent disposed on or within the tobacco rod may have about the same or similar hardness or firmness as a tobacco rod that is free of this binding agent disposed on or within the tobacco rod.

The plasticizer can be any useful plasticizer material allowed in the manufacture of a smoking article. The plasticizer may include a glycol, sugar alcohol, or glycerol. Preferred plasticizers include glycerol, propylene glycol and sorbitol. The plasticizer may be included in any useful amount. The plasticizer may be present in the binding agent in an amount from at least about 1 weight percent or about at least 5 weight percent or at least about 10 weight percent or in a range from about 1 to about 30 weight percent or in a range from about 5 to about 30 weight percent.

Preferably, substantially all of the shorts at the open end of the tobacco rod are adhered to the cut tobacco filler or loose tobacco filling in the open end of the tobacco rod. Thus, for example, in the above-defined end region where adhesion of the shorts to the cut tobacco filler or loose tobacco filling is provided, suitably no more than about 10%, 5%, 2% or 1 % of the tobacco rod material (tobacco filling) by weight will pass a 2mm sieve. Suitably, the amount of material in this region passing a 2mm sieve is reduced by at least about 50%, 75% or 90% relative to the tobacco material without bonding of shorts to the cut filler or tobacco filling. Additionally or alternatively, suitably the amount of material in this region passing a 1mm sieve is reduced by at least about 50%, 75% or 90% relative to the tobacco material without bonding of shorts to the cut tobacco filler or loose tobacco filling.

The binding agent may be present on the loose tobacco filling or cut tobacco filler at the open end in any useful amount. The binding agent may be present on the tobacco filling or in the tobacco rod in an amount in a range from about 0.1 mg to about 5 mg, or from about 0.2 mg to about 3 mg or from about 0.5 mg to about 1.5 mg.

The aqueous solution of binder material may have any useful concentration of binder material. Preferably the aqueous solution of binder material (liquid composition) has a concentration of binder material of at least about 25 mg/ml or at least about 30 mg/ml or at least about 35 mg/ml. Utilizing these higher solids concentration aqueous solutions (liquid compositions) of binder material can also assist in reducing absorption and staining of the paper wrapper. The liquid composition may be applied at an amount in a range from about 5 mg to about 75 mg or in a range of about 10 mg to about 50 mg or in a range of about 15 mg to about 40 mg. Tobacco rods described herein may be formed by the steps of: (1) forming a tobacco rod comprising loose tobacco filling or cut tobacco filler circumscribed by a paper wrapper with an open end, and an open end region adjacent to the open end; (2) applying a liquid composition to the loose tobacco filling or cut tobacco filler at the open end, the liquid composition comprising a binding agent dissolved in water; and (3) removing at least a portion of the water from the liquid composition to form adhered tobacco filling or adhered cut tobacco filler at the open end. The open end region of the paper wrapper being hydrophobic due to hydrophobic groups covalently bonded to the paper prior to forming the tobacco rod or addition of tobacco filling.

The liquid composition may be applied to the loose tobacco filling or cut tobacco filler at the open end by spraying onto the open end, or by injection into the open end, or by brushing or dipping the open end into the liquid composition. The liquid composition may be applied to only a portion of the loose tobacco filling or cut tobacco filler forming the tobacco rod. Preferably the liquid composition may be applied to only the end region portion of the loose tobacco filling or cut tobacco filler forming the tobacco rod. The application of the liquid composition may be combined with application of suction to the tobacco rod to draw the fluid into the loose tobacco filling or cut tobacco filler. The liquid composition may be a liquid solution or dispersion, or it may be an aerosol. In embodiments, the liquid composition is a foamed liquid, for example having a foaming ratio of at least about 10:1. Methods of making and applying foamed liquids are described in US- A-4785831.

The liquid composition may be applied to individual tobacco rod open ends, or it could be applied onto the open end of a bundle of tobacco rods on the packer or in a special tray at a special station on the machine using an array of injectors or sprayers. An example of a station for applying liquid to tobacco rod open ends mounted on a rotary drum is shown in US-A-5261423. Suitably, the liquid may be applied through a mask having holes directly aligned with the tobacco rod open ends to reduce liquid over spray outside the target area. Utilizing the paper wrapper having a hydrophobic end region, allows the liquid composition to be applied broadly without regard for avoiding over-spraying outside the target area.

Following application of the liquid composition, the tobacco rod is dried to remove the solvent (such as, water). This may be done, for example, by the application of heated or hot air to the tobacco rod.

The paper wrapper has a hydrophobic region that is coextensive with at least a length of the tobacco filling or cut tobacco filler adhered with binding material. The hydrophobic region may define, at least or only, the upstream-most end region of the tobacco rod. Alternatively, the hydrophobic region may define the upstream-most end region of the tobacco rod and the remaining portion of the paper wrapper is not hydrophobic. The upstream-most end region of the tobacco rod may be only the final about 15 mm, or only the final about 10 mm, or only the final about 6 mm of the tobacco rod open end. The entire length of the tobacco rod paper wrapper may be hydrophobic.

The hydrophobic region of the paper wrapper may have substantially the same or similar permeability as the untreated or non-hydrophobic region of the paper wrapper. Permeability of paper wrapper is determined by utilizing the International Standard test method ISO 2965:2009 and the result is presented as cubic centimetres per minute per square centimetre and referred to as "CORESTA units". In many embodiments, the permeability of the untreated paper wrapper (that is, with no hydrophobic treatment) may be within about 20% or within about 10% of the permeability of the treated paper wrapper (that is, hydrophobic region).

The paper wrapper is formed of a material with pendent protogenic groups. Paper material with pendent protogenic (such as, hydroxyl) groups includes cellulosic material such as hemp, flax, esparto, wood, jute, rice, or eucalyptus. The paper wrapper may also include one or more conventional paper additives. The paper wrapper may have a weight from about 10 to about 50 grams per square meter or from about 15 to about 40 grams per square meter. The paper wrapper may have a thickness from about 10 to 100 micrometres or from about 30 to 70 micrometres.

The tobacco rod can have any useful longitudinal dimension (length). In many embodiments the tobacco rod has a longitudinal dimension (length) in a range from about 30 mm to about 80 mm or from about 40 mm to about 70 mm. The diameter of the tobacco rod is from about 4 mm to about 10 mm or from about 6 mm to about 8 mm.

Hydrophobic groups are covalently bonded to the inner surface or the outer surface of the paper wrapper surrounding the tobacco filling. It has been found that covalently bonding hydrophobic groups (as described herein) to only one side or major surface of the paper wrapper may impart hydrophobic properties to the opposing side or major surface of the paper wrapper.

The hydrophobic region of the paper wrapper may inhibit the transfer, absorption and migration of water and binding material and staining. In particular, the hydrophobic region of the paper wrapper may inhibit the absorption of the aqueous solution of binder material and reduce or prevent staining associated with such process. The hydrophobic region of the paper wrapper may have a Cobb water absorption (IS0535:1991) value (at 60 seconds) of less than about 40 g/m ² , less than about 35 g/m ² , less than about 30 g/m ² , or less than about 25 g/m ² .

The hydrophobic region of the paper wrapper has a water contact angle of at least about 90 degrees, at least about 95 degrees, at least about 100 degrees, at least about 110 degrees, at least about 120 degrees, at least about 130 degrees at least about 140 degrees, at least about 150 degrees, at least about 160 degrees, or at least about 70 degrees. Hydrophobicity is determined by utilizing the TAPPI T558 om-97 test and the result is presented as an interfacial contact angle and reported in "degrees" and can range from near zero degrees to near 180 degrees. Where no contact angle is specified along with the term hydrophobic, the water contact angle is at least 90 degrees.

The hydrophobic region may be uniformly present along the length of the paper wrapper defining the tobacco rod. Preferably the hydrophobic region is selectively formed at the open end region of the paper wrapper defining the tobacco rod as described above.

The hydrophobic surface or region of the cellulosic material forming the paper wrapper can be formed with any suitable hydrophobic reagent or hydrophobic group. The hydrophobic reagent is preferably chemically bonded to the cellulosic material or pendent protogenic groups of the cellulosic material forming the paper wrapper. In many embodiments the hydrophobic reagent is covalently bonded to the cellulosic material or pendent protogenic groups of the cellulosic material. For example, the hydrophobic group is covalently bonded to pendent hydroxyl groups of cellulosic material forming the paper wrapper. A covalent bond between structural components of the cellulosic material and the hydrophobic reagent can form hydrophobic groups that are more securely attached to the paper material than simply disposing a coating of hydrophobic material on the cellulosic material forming the paper wrapper. By chemically bonding the hydrophobic reagent at the molecular level in situ rather than applying a layer of hydrophobic material in bulk to cover the surface allows the permeability of the paper to be better maintained, since a coating tends to cover or block pores in the cellulosic material forming the continuous sheet and reduce the permeability. Chemically bonding hydrophobic groups to the paper in-situ can also reduce the amount of material required to render the surface of the paper wrapper hydrophobic. The term "in-situ" as used herein refers to the location of the chemical reaction which takes place on or near the surface of the solid material that forms the hydrophobic region of the paper wrapper, which is distinguishable from a reaction with cellulose dissolved in a solution. For example, the reaction takes place on or near the surface of cellulosic material forming the hydrophobic region of the paper wrapper which comprises cellulosic material in a heterogenous structure. However, the term "in-situ" does not require that the chemical reaction takes place directly on cellulosic material forming the hydrophobic region of the paper wrapper.

The hydrophobic reagent may comprises an acyl group or fatty acid group. The acyl group or fatty acid group or mixture thereof can be saturated or unsaturated. A fatty acid group (such as a fatty acid halide) in the reagent can react with pendent protogenic groups such as hydroxyl groups of the cellulosic material to form an ester bond covalently bonding the fatty acid to the cellulosic material. In essence, these reactions with the pendant hydroxyl groups can esterify the cellulosic material.

In one embodiment of the invention, the acyl group or fatty acid group includes a C12-C30 alkyl (an alkyl group having from 12 to 30 carbon atoms), a C14-C24 alkyl (an alkyl group having from 14 to 24 carbon atoms) or preferably a Ci ₆ -C ₂ o alkyl (an alkyl group having from 16 to 20 carbon atoms). Those skill in the art would understand that the term "fatty acid" as used herein refers to long chain aliphatic, saturated or unsaturated fatty acid that comprises 12 to 30 carbon atoms, 14 to 24 carbon atoms, 16 to 20 carbon atoms or that has greater than 15, 16, 17, 18, 19, or 20 carbon atoms. In various embodiments, the hydrophobic reagent includes an acyl halide, a fatty acid halide, such as, a fatty acid chloride including palmitoyl chloride, stearoyl chloride or behenoyl chloride, a mixture thereof, for example. The in situ reaction between fatty acid chloride and cellulosic material forming the continuous sheet results in fatty acid esters of cellulose and hydrochloric acid.

Any suitable method can be utilized to chemically bond the hydrophobic reagent or group to the cellulosic material forming the hydrophobic region of the paper wrapper. The hydrophobic group is covalently bonded to the cellulosic material by diffusion of a fatty acid halide on its surface without using a solvent.

As one example, an amount of hydrophobic reagent, such as an acyl halide, a fatty acid halide, a fatty acid chloride, palmitoyl chloride, stearoyl chloride or behenoyl chloride, a mixture thereof, is deposited without solvent (solvent-free process) at the surface of the paper wrapper at a controlled temperature, for example, droplets of the reagents forming 20-micrometer regularly- spaced circles on the surface. The control of the vapour tension of the reagent can promote the propagation of the reaction by diffusion with the formation of ester bonds between fatty acid and cellulose while continuously withdrawing unreacted acid chloride. The esterification of cellulose is in some cases based on the reaction of alcohol groups or pendent hydroxyl groups of cellulose with an acyl halide, such as an acyl chloride including a fatty acid chloride. The temperature that can be used to heat the hydrophobic reagent depends on the chemical nature of the reagent and for fatty acid halides, it ranges from about 120°C to about 180°C.

The hydrophobic reagent can be applied to the cellulosic material of the paper wrapper in any useful amount or basis weight. In many embodiments the basis weight of the hydrophobic reagent is less than about 3 grams per square meter, less than about 2 grams per square meter, or less than about 1 gram per square meter or in a range from about 0.1 to about 3 grams per square meter, from about 0.1 to about 2 grams per square meter, or from about 0.1 to about 1 gram per square meter. The hydrophobic reagent can be applied or printed on the paper wrapper surface and define a uniform or non-uniform pattern.

Preferably the hydrophobic region of the paper wrapper is formed by reacting a fatty acid ester group or a fatty acid group with pendent hydroxyl groups on the cellulosic material of the paper wrapper to form a hydrophobic surface. The reacting step can be accomplished by applying a fatty acid halide (such as chloride, for example) which provides the fatty acid ester group or a fatty acid group to chemically bond with pendent hydroxyl groups on the cellulosic material of the paper to form a hydrophobic surface. The applying step can be carried out by loading the fatty acid halide in liquid form onto a solid support, such as a brush, a roller, or an absorbent or non- absorbent pad, and then contacting the solid support with a surface of the paper. The fatty acid halide can also be applied by printing techniques, such as gravure, flexography, ink jet, heliography, by spraying, by wetting, or by immersion in a liquid comprising the fatty acid halide. The applying step can deposit discrete islands of reagent forming a uniform or non-uniform pattern of hydrophobic areas on the surface of the paper. The uniform or non-uniform pattern of hydrophobic areas on the elongated tube paper can be formed of at least about 100 discrete hydrophobic islands, at least about 500 discrete hydrophobic islands, at least about 1000 discrete hydrophobic islands, or at least about 5000 discrete hydrophobic islands. The discrete hydrophobic islands can have any useful shape such as a circle, rectangle or polygon. The discrete hydrophobic islands can have any useful average lateral dimension. In many embodiments the discrete hydrophobic islands have an average lateral dimension in a range from 5 to 100 micrometres, or in a range from 5 to 50 micrometres. To aid diffusion of the applied reagent on the surface, a gas stream can also be applied. Apparatus and processes such as those described in US patent publication 2013/0236647, incorporated herein by reference in its entirety, can be used to produce the hydrophobic region of the paper wrapper.

A hydrophobic region of the paper wrapper may be produced by a process comprising applying a liquid composition comprising an aliphatic acid halide (preferably a fatty acid halide) to at least one surface of the paper wrapper, optionally applying a gas stream to the surface to aid diffusion of the applied fatty acid halide, and maintaining the surface at a temperature about 120°C to about 180°C, wherein the fatty acid halide reacts in situ with the hydroxyl groups of the cellulosic material in the paper resulting in the formation of fatty acid esters. Preferably, the paper is made of cellulose, and the fatty acid halide is stearoyl chloride, palmitoyl chloride, or a mixture of fatty acid chlorides with 16 to 20 carbon atoms in the acyl group. The hydrophobic paper produced by a process described hereinabove is thus distinguishable from material made by coating the surface with a layer of pre-made fatty acid ester of cellulose. The hydrophobic region of the paper wrapper may be produced by a process of applying the liquid reagent composition to the at least one surface of an elongated tube paper at a rate of in a range from about 0.1 to about 3 grams per square meter, or from about 0.1 to about 2 grams per square meter, or from about 0.1 to about 1 gram per square meter. The liquid reagent applied at these rates renders the surface of the paper hydrophobic.

In many embodiments, the thickness of the paper wrapper allows the hydrophobic groups or reagent applied to one surface to spread onto the opposing surface effectively providing similar hydrophobic properties to both opposing surfaces. In one example, the thickness of the paper wrapper was about 43 micrometres and both surfaces were rendered hydrophobic by the gravure (printing) process using stearoyl chloride as the hydrophobic reagent to one surface.

In some embodiments, the material or method to create the hydrophobic nature of the hydrophobic paper wrapper does not substantially affect the permeability of the paper wrapper. Preferably, the reagent or method to create the hydrophobic region of the paper wrapper changes the permeability of the paper wrapper (as compared to the untreated paper wrapper) by less than about 10% or less than about 5% or less than 1%.

In many embodiments the hydrophobic surface can be formed by printing reagent along a specified length of the paper wrapper. Any useful printing methods can be utilized. The reagent can include any useful hydrophobic groups that can be reacted to chemically bond to the paper wrapper pendent groups of the cellulosic material.

In many embodiments the hydrophobic surface can be formed by printing reagent along the length of the cellulosic material. Any useful printing methods can be utilized such as gravure, inkjet and the like. The reagent can include any useful hydrophobic groups that can be covalently bonded to the cellulosic material or pendent groups of the cellulosic material.

The binding material and hydrophobic material utilized herein has a minimal effect on the resistance to draw (RTD) of the smoking article. Suitably, the draw resistance is increased by less than about 10%, or less than about 5% or less than about 2%, compared to a smoking article of the same manufacture but without the binding material or the hydrophobic material. The RTD of a smoking article refers to the static pressure difference between the two ends of the specimen when it is traversed by an air flow under steady conditions in which the volumetric flow is 17.5 millilitres per second at the output end. The RTD of a specimen can be measured using the method set out in ISO Standard 6565:2002 with any ventilation (if present) blocked.

The tobacco rods described herein prevents loose tobacco filling or cut tobacco filler from falling out of the end of the tobacco rod while maintaining the color and structural integrity of the tobacco rod. The tobacco rods described herein have been shown to reduce loose ends by at least about 50% or at least about 75%, or at least about 90% as compared to tobacco rods that do not include binder material and a paper wrapper hydrophobic end region. The stability of the tobacco rod open end may be determined by utilizing the Borgwaldt Loose Ends test, as described below.

The tobacco rods described herein can exhibit a Borgwaldt Loose Ends test result of less than about 5 mg of tobacco fallout per open end or less than about 3 mg of tobacco fallout per open end or less than about 2 mg of tobacco fallout per open end or less than about 1 mg of tobacco fallout per open end or less than about 0.5 mg of tobacco fallout per open end.

All scientific and technical terms used herein have meanings commonly used in the art unless otherwise specified. The definitions provided herein are to facilitate understanding of certain terms used frequently herein.

As used in this specification and the appended claims, the singular forms "a", "an", and "the" encompass embodiments having plural referents, unless the content clearly dictates otherwise.

As used in this specification and the appended claims, the term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise.

As used herein, "have", "having", "include", "including", "comprise", "comprising" or the like are used in their open ended sense, and generally mean "including, but not limited to". It will be understood that "consisting essentially of, "consisting of, and the like are subsumed in "comprising," and the like.

The words "preferred" and "preferably" refer to embodiments of the invention that may afford certain benefits under certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the disclosure, including the claims.

FIG. 1 is a schematic perspective view of an illustrative smoking article.

The schematic drawing is not necessarily to scale and is presented for purposes of illustration and not limitation. The drawing depicts one or more aspects described in this disclosure. However, it will be understood that other aspects not depicted in the drawing fall within the scope and spirit of this disclosure.

Referring now to FIG. 1, an illustrative smoking article 10 includes a tobacco rod 25 in axial alignment with a filter element 35. A paper wrapper 15 defines a tobacco rod cavity and circumscribes loose tobacco filling 20. The smoking article 10 has a generally cylindrical shape having a first end 12 and an opposing second end 14. A mouthpiece segment 30 is at the first end 12 and an open end is at the second end 14.

A hydrophobic region 17 of the paper wrapper 15 is adjacent to the open end or second end 14. The hydrophobic region 17 comprises hydrophobic groups covalently bonded to the paper wrapper 15. The mouthpiece segment 30 can include a filter element 35.

A binding agent 22 is disposed on the loose tobacco filling 20 at the open end or second end 14. The binding agent 22 adheres the loose tobacco filling 20 together at the open end or second end 14. The remaining length of the tobacco rod 25 may contain loose tobacco cut filler that is not adhered together.

The exemplary embodiments described above are not limiting. Other embodiments consistent with the exemplary embodiments described above will be apparent to those skilled in the art. In the following, non-limiting examples provide illustrative embodiments of the activated carbon particles and methods described above. These examples are not intended to provide any limitation on the scope of the disclosure presented herein.

EXAMPLES

The examples describe the determination of cigarette loose ends by measuring the amount of tobacco fallout from the exposed ends of a number of cigarettes. Cigarettes having at least a hydrophobic end region, as described above were tested utilizing a Borgwaldt E44 instrument. The Borgwaldt E44 instrument is commercially available from Borwalt Korber Solutions and is known as a "Ends Tester" and quantifies an amount of "loose ends" that fallout of the open end of a cigarette.

The Borgwaldt E44 instrument simulates the mechanical handling of cigarettes during the production process, the cigarettes are subjected to a rolling and falling motion in a "cigarette cage" for a certain period of time. The quantity of tobacco dropped out of the ends is an indication of the stability of the cigarette ends.

This Borgwaldt Loose Ends test consists of tumbling a specified number of cigarettes for three minutes at 90 rpm with the Borgwaldt E44 instrument. The quantity of tobacco fallout is then weighed. To be in accordance with ISO 3550-1 1197, the mass of tobacco fallout is reported in mg per open end.

A reference sample of 20 cigarettes having no added binding material was tested in the Borgwaldt E44 instrument. A total of 190 mg of tobacco fallout was measured equating to 9.5 mg of tobacco fallout per open end utilizing the Borgwaldt Loose Ends test. A first sample of 20 cigarettes having the open end of each cigarette brushed with about 20 mg of and aqueous binder solution having a binder concentration of 40 mg/ml of carboxymethylcellulose sodium salt (commercially available from Fluka BioChemika). About 0.77 mg of carboxymethylcellulose sodium salt was deposited on the open end tobacco filling. The first sample was tested as described about for the reference sample. A total of 40 mg of tobacco fallout was measured equating to 2 mg of tobacco fallout per open end utilizing the Borgwaldt Loose Ends test.

A second sample of 20 cigarettes having the open end of each cigarette brushed with about 35 mg of aqueous binder solution having a binder concentration of 40mg of carboxymethylcellulose sodium salt (commercially available from Fluka BioChemika). About 1.35 mg of carboxymethylcellulose sodium salt was deposited on the open end tobacco filling. The second sample was tested as described about for the reference sample. A total of 10 mg of tobacco fallout was measured equating to 0.5 mg of tobacco fallout per open end utilizing the Borgwaldt Loose Ends test.

The results presented in this Example, illustrates that carboxymethylcellulose sodium salt can reduce loose ends. Other binder materials, described herein may also be used.

Thus, methods, systems, devices, compounds and compositions for SMOKING ARTICLE WITH HYDROPHOBIC WRAPPER AND REDUCED TOBACCO LOOSE ENDS are described. Various modifications and variations of the invention will be apparent to those skilled in the art without departing from the scope and spirit of the invention. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention which are apparent to those skilled in chemistry; chemical engineering; cigarette manufacturing; or related fields are intended to be within the scope of the following claims.