Technical Field

The invention relates to a smoking article and an attachable unit therefor.

Background

Cigarettes and other smoking articles produce an aerosol, smoke in the case of cigarettes, which is inhaled by a user. Separate filter units may be attached to smoking articles to modify the aerosol before it reaches the user's mouth.

Summary

According to a first aspect of the invention, there is provided an attachable unit to be attached to a smoking article rod by a user to modify an aerosol generated by the smoking article rod, the attachable unit comprising a recess to receive at least a portion of the smoking article rod when the attachable unit is attached to the smoking article rod, and a raised area extending from an inner surface of the recess for contacting an outer surface of the smoking article rod when the at least a portion of the smoking article rod is received in the recess. The attachable unit can further comprise a sleeve, wherein at least a portion of the sleeve defines the recess. The attachable unit can further comprise a cylindrical element and a sheet material at least partially surrounding the cylindrical element and forming the sleeve. The attachable unit can be arranged such that the smoking article rod and attachable unit are aligned on a longitudinal axis when the attachable unit is attached to the smoking article rod and wherein the recess of the attachable unit is formed by the sheet material extending longitudinally beyond a longitudinal end of the cylindrical element, and wherein the raised area extends around an inner surface of the sheet material.

The attachable unit can be arranged such that the smoking article rod and attachable unit are aligned on a longitudinal axis when the attachable unit is attached to the smoking article rod and wherein the recess of the attachable unit is formed by a tubular element held within a portion of the sheet material extending longitudinally beyond a longitudinal end of the cylindrical element, and wherein the raised area extends around an inner surface of the tubular element. The raised area can be annular and/ or can extend circumferentially around the inner circumferential surface of the recess. The raised area can be for contacting an outer circumferential surface of the smoking article rod when the at least a portion of the smoking article rod is received in the recess.

The raised area can comprise a seal which is configured to restrict the ingress of air into the smoking article between the inner surface of the recess of the attachable unit and the outer surface of the smoking article rod.

The raised area can comprise a deformable material such as a resiliently deformable material.

The raised area can comprise an adhesive. The element can comprise filtration material such as fibrous filtration material.

The element can comprise a flavour modifying agent.

According to the first aspect of the invention, there is further provided a kit comprising an attachable unit according to the first aspect of the invention and a smoking article rod, the attachable unit to be attached to the smoking article rod by a user. According to the first aspect of the invention, there is further provided a smoking article comprising a smoking article rod and an attachable unit according to the first aspect of the invention attached to the smoking article rod, wherein at least a portion of the smoking article rod is received in the recess and the raised area is in contact with the outer surface of the smoking article rod.

According to a second aspect of the invention, there is provided an attachable unit to be attached to a smoking article rod by a user to modify an aerosol generated by the smoking article rod, the attachable unit comprising a cylindrical element and a tubular element, wherein the cylindrical element and tubular element are aligned on a longitudinal axis and connected together by a sheet material wrapping at least a portion of the cylindrical element and tubular element and wherein the tubular element defines a recess to receive at least a portion of the smoking article rod when the attachable unit is attached to the smoking article rod.

The tubular element can comprise a resiliently deformable material. The tubular element can have a wall thickness of between 0.2mm and 5mm, between 0.2mm and 2mm, between 0.2mm and imm or between 0.2mm and 0.4mm. The tubular element can have an internal diameter of between 4mm and 10mm and a manufacturing tolerance for said internal diameter of less than +/- 0.1mm, +/- 0.05mm, +/- 0.04mm, +/- 0.03mm or +/- 0.02mm.

The attachable unit can be arranged such that the smoking article rod and attachable unit are aligned on a longitudinal axis when the attachable unit is attached to the smoking article rod and wherein a longitudinal end surface of the cylindrical element is arranged to abut a longitudinal end surface of the smoking article rod when the attachable unit is attached to the smoking article rod.

The element can comprise filtration material, such as fibrous filtration material.

The element can comprise a flavour modifying agent.

The attachable unit can further comprise a raised area extending from an inner surface of the recess for contacting an outer surface of the smoking article rod when the at least a portion of the smoking article rod is received in the recess. The raised area can be annular and can extends circumferentially around the inner circumferential surface of the recess.

According to the second aspect of the invention, there is further provided a kit comprising an attachable unit according to the second aspect of the invention and a smoking article rod, the attachable unit to be attached to the smoking article rod by a user.

According to the second aspect of the invention, there is further provided a smoking article comprising a smoking article rod and an attachable unit according to the second aspect of the invention attached to the smoking article rod, wherein at least a portion of the smoking article rod is received in the recess defined by the tubular element. According to a third aspect of the invention, there is provided an attachable unit to be attached to a smoking article rod by a user to modify an aerosol generated by the smoking article rod, the smoking article rod comprising a first recess, the attachable unit comprising an element arranged to be inserted at least partially into the first recess of the smoking article rod and a second recess arranged to receive at least a portion of the smoking article rod.

The second recess can surround the element.

The attachable unit can further comprise an outer sleeve surrounding the element, wherein the element comprises a cylindrical element and the second recess is formed between the cylindrical element and the outer sleeve.

The attachable unit can further comprise a cylindrical body of material surrounded by the sleeve, the cylindrical body of material having a diameter greater than the cylindrical element and the cylindrical element arranged coaxially with the cylindrical body of material and extending from an end thereof.

The attachable unit can be arranged such that the smoking article rod and attachable unit are aligned on a longitudinal axis when the attachable unit is attached to the smoking article rod and wherein the cylindrical body of material has a longitudinal end surface which is arranged to abut a longitudinal end surface of the smoking article rod when the attachable unit is attached to the smoking article rod.

The element can comprise filtration material such as fibrous filtration material. The element can comprise a flavour modifying agent.

The attachable unit can further comprise a raised area extending from an inner surface of the second recess for contacting an outer surface of the smoking article rod when the at least a portion of the smoking article rod is received in the second recess. According to the third aspect of the invention, there is further provided a kit comprising an attachable unit according to the third aspect of the invention and a smoking article rod, the attachable unit to be attached to the smoking article rod by a user.

According to the third aspect of the invention, there is further provided a smoking article comprising a smoking article rod comprising a first recess and an attachable unit according to the third aspect of the invention attached to the smoking article rod, wherein the element of the attachable unit is inserted at least partially into the first recess of the smoking article rod and at least a portion of the smoking article rod is received in the second recess of the attachable unit.

Brief Description of the Drawings

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

Figure 1 is a side-on cross sectional view of an example of an attachable unit and a smoking article rod which can be attached to form a smoking article;

Figure 2 is a side-on cross sectional view of another example of an attachable unit and a smoking article rod which can be attached to form a smoking article;

Figure 3 is a side-on cross sectional view of a further example of an attachable unit and a smoking article rod which can be attached to form a smoking article; and

Figure 4 is a side-on cross sectional view of another example of an attachable unit and a smoking article rod which can be attached to form a smoking article. Detailed Description

As used herein, the term "smoking article" includes combustible smoking articles such as cigarettes, cigars and cigarillos whether based on tobacco, tobacco derivatives, expanded tobacco, reconstituted tobacco or tobacco substitutes and also heating devices such as heat-not-burn (HnB) devices, which release compounds from substrate materials, such as tobacco, without burning the substrate material, and other nicotine delivery products such as aerosol generation devices including e-cigarettes. The smoking article may be provided with a filter for the gaseous flow drawn by the smoker.

Smoking articles such as cigarettes and their formats are often named according to the cigarette length: "regular" (typically in the range 68 - 75 mm, e.g. from about 68 mm to about 72 mm), "short" or "mini" (68 mm or less), "king-size" (typically in the range 75 - 91 mm, e.g. from about 79 mm to about 88 mm), "long" or "super-king" (typically in the range 91 - 105 mm, e.g. from about 94 mm to about 101 mm) and "ultra-long"

(typically in the range from about 110 mm to about 121 mm). They are also named according to the cigarette circumference: "regular" (about 23 - 25 mm), "wide" (greater than 25 mm), "slim" (about 22 - 23 mm), "demi-slim" (about 19 - 22 mm), "super-slim" (about 16 - 19 mm), and "micro-slim" (less than about 16 mm). Accordingly, a cigarette in a king-size, super-slim format will, for example, have a length of about 83 mm and a circumference of about 17 mm. Cigarettes in the regular, king-size format are preferred by many customers, namely with a circumference of from 23 to 25 mm and an overall length of from 75 to 91 mm.

Each format may be produced with filters of different lengths, smaller filters being generally used in formats of smaller lengths and circumferences. Typically the filter length will be from about 15 mm, associated with short, regular formats, to 30 mm, associated with ultra-long super-slim formats. The tipping paper will have a greater length than the filter, for example from 3 to 10 mm longer, such that the tipping paper covers the filter and overlaps the tobacco rod to connect the filter to the tobacco rod. Smoking articles described herein can be made in, but are not limited to, any of the above formats.

In the figures described herein, like reference numerals are used to illustrate equivalent features, articles or components.

Figure 1 is a side-on cross sectional view of an example of an attachable unit 3 and a smoking article rod 2 which can be attached or coupled together by a user to form a smoking article 100. The attachable unit 3 is configured to modify one or more properties of an aerosol generated by the smoking article rod 2.

The attachable unit 3 comprises a recess 30 into which at least a portion of the smoking article rod 2 can be received when the attachable unit 3 is attached to the smoking article rod 2. In the present example, the attachable unit 3 comprises a cylindrical element 21 which is surrounded by a sheet material 22 forming a sleeve around the cylindrical element 21. In alternative examples, the sleeve can be formed in other ways, for instance from plastic or other materials. In the present example, the cylindrical element 21 comprises filter material, in the present case cellulose acetate tow, circumferentially wrapped in the sheet material 22, although the attachable unit 3 can be formed in other ways. In the present case, the sheet material 22 comprises stiff paper.

The attachable unit is arranged such that the smoking article rod 2 and attachable unit 3 are aligned on a longitudinal axis when the attachable unit 3 is attached to the smoking article rod 2. The cylindrical element 21 comprises first and second longitudinal ends 23, 24, which, in the present example are exposed, allowing smoke or other aerosols to pass longitudinally through the cylindrical element 21. As illustrated, to form the recess 30, the sheet material 22 extends longitudinally beyond the first longitudinal end surface 23 of the cylindrical element 21. The recess 30 is formed by the first longitudinal end surface 23 of the cylindrical element 21 together with the inner surface of the portion of the sheet material 22 which extends longitudinally beyond the first longitudinal end surface 23 of the cylindrical element 21. The sheet material 22 extends up to the second longitudinal end surface 24 of the cylindrical element 21, although can alternatively extend beyond the second longitudinal end surface 24, forming a further recess (not shown), or can be arranged to stop short of the longitudinal end surface 24, such that the sheet material 22 does not surround the full length of the cylindrical element 21.

A raised area 50 extends at least substantially around an inner surface of the recess 30, in the present example around the inner surface of the sheet material 22. The raised area 50 in the present example is annular, i.e. it forms a ring extending

circumferentially around the inner surface of the sheet material 22. The raised area 50 may comprise, but is not limited to, one or more layers of material such as one or more adhesive layers or one or more layers of paper, moulded pulp material, card, rubber or plastic material. The raised area 50 maybe made out of a deformable material such as a resiliently deformable material and/or a material which is impermeable to air, restricts or substantially restricts the passage of air through the material. The raised area 50 can be formed by embossing the sheet material 22 such that a region of the material 22 protrudes into the recess 30. The smoking article rod 2 shown in Figure 1 has a tobacco rod 4 longitudinally connected, end-on, to a filter 6. An external end surface 16 of the filter 6 at the end opposite to the end of the filter 6 facing the tobacco rod 4 defines a mouth end surface 16 of the smoking article rod 2. The smoking article rod 4 can be a conventional smoking article, such as a cigarette, including any of the smoking articles and smoking article formats described herein. In the present example, the tobacco rod 4 is wrapped in a wrapping material 5, in this case cigarette paper. The filter 6 is, in the present example, formed from cellulose acetate tow wrapped in a plug wrap 9. The tobacco rod 4 and filter 6 are connected by a tipping material 14 overlaying the filter 6 and partially overlaying the wrapping material 5. The filter 6 may comprise two or more filter sections forming the filter 6, which can be connected together using a further plug wrap (not shown), prior to connection of the filter 6 to the tobacco rod 4 using the tipping material 14.

In use, the smoking article 100 can be provided to users with the attachable unit 3 and smoking article rod 2 as separate components, for instance packaged separately or packaged together as a kit of parts for producing a smoking article 100. Prior to a user first using the smoking article rod 2, the attachable unit 3 can be attached to the smoking article rod 2 by inserting the mouth-end of the smoking article rod 2 into the recess 30 of the attachable unit 3. When the attachable unit 3 is attached to the smoking article rod 2, the first longitudinal end surface 23 of the cylindrical element 21 abuts the mouth end surface 16 of the filter 6 of the smoking article rod 2. Alternatively, the attachable member 3 may be attached to the smoking article rod 2 so that there is a gap between the longitudinal end surface 23 and the mouth end surface 16. The raised area 50 contacts an outer surface of the smoking article rod 2, in particular a circumferential outer surface, when the smoking article rod 2 is received in the recess 30.

The user can select whether or not to attach the attachable unit 3 to the smoking article rod 2 prior to smoking the smoking article 100, and can in this way control the length of filter of the smoking article 100 and therefore the level of filtration of the aerosol generated by the smoking article rod 2. The attachable unit 3 can also include additives or agents for modifying the aerosol, in the present case smoke, generated by the smoking article rod 2. For instance, in the present example, a capsule containing a flavour additive (not shown) is located within the cylindrical element 21. The capsule has a liquid centre and a frangible outer shell which can be broken by a user by squeezing the attachable unit 3, to thereby release the flavour additive. The flavour additive is transferred to the aerosol generated by the smoking article rod 2 as the smoking article 100 is smoked. In alternative examples, the attachable unit 3 may include alternative additives or agents for modifying the aerosol generated by the smoking article rod 2, such as granules of activated carbon or other adsorbents, humectants, diluents and suchlike.

In the present example, the raised area 50 comprises an adhesive to attach the attachable unit 3 to the smoking article rod 2. Suitable adhesive materials for the raised area 50 include a natural adhesive (bio-adhesive) and/or a synthetic adhesive. The synthetic adhesive maybe based on any of: an elastomer material; a thermoplastic material; an emulsion and a thermosetting material such as epoxy, polyurethane, cyanoacrylate or acrylic. The adhesive may be any non-reactive adhesive such as: a drying adhesive, a pressure sensitive adhesive, a contact adhesive, a hot adhesive. The adhesive maybe a reactive adhesive. The adhesive maybe a permanently tacky adhesive, for instance allowing the attachable unit 3 and smoking article rod 2 to be separated and repositioned. The parts of the sheet material 22 on which the raised area 50 is disposed may be pressed against the outer surface of the smoking article rod 2 by the user, in order to adhere the attachable unit 3 to the smoking article rod 2.

The raised area 50 can alternatively or additionally form a seal or sealing element used to seal at least a part of the interface between the sheet material 22 and the smoking article rod 2 and inhibit the ingress of gases (such as air) that would normally enter into the smoking article 100 via a gap between the outer surface of the smoking article rod 2 and the inner surface of the sheet material 22. In this case, the raised area 50 may comprise a body which is air impermeable in at least one direction and/or resiliently deformable. Due to limitations in the manufacturing tolerance of the components of a smoking article, the distance between surfaces such as the outer surface of the portion of the smoking article rod 2 inserted into the recess 30 and the inner surface of the recess 30 can vary. If external air is allowed to enter the smoking article 100 between the attachable unit 3 and the smoking article rod 2, this can result in a level of ventilation exhibited by the smoking article 100 which cannot be accurately controlled from one article to another. Restricting the ingress of air therefore provides a greater degree of control of the airflow into and through the smoking article 100. For instance, ventilation can be provided into the filter 6 using perforations through the plug wrap 9 and tipping 14 in the conventional manner. The raised area 50 may comprise any suitable thickness (i.e. the distance between the inner surface of the sheet material 22 and the innermost surface 50a of the raised area 50), for example between 0.1mm and 2 mm, or between 0.1mm and imm. The raised area can, for instance, have a thickness of 0.5mm.

In practice, the correspondence between the dimensions of the recess 30 and those of the smoking article rod 2 will depend on the materials used to form these components and the desired closeness of the fit between them. It is likely to be preferable that the dimensions of the recess 30 are slightly larger than the dimensions of the smoking article rod 2, to facilitate insertion of the smoking article rod 2 into the recess 30.

In the example of Figure 1, the recess 30 has an internal diameter of 8.2mm and the smoking article rod 2 has an external diameter of 7.8 mm. In alternative examples, the internal diameter of the recess 30 can have other values, for instance diameters in the range from 4mm to 10mm. In the example of Figure 1, the recess 30 has an internal length of 12mm. In alternative examples, the internal length of the recess 30 can have other values, for instance values in the range from 5mm to 30mm.

The longitudinal end surface 23 is configured to at least partially face the mouth end surface 16 of the smoking article rod 2 when the attachable unit 3 is attached to the smoking article rod 2.

The raised area 50 can be formed by a resiliently deformable material, so that it can deform to receive the smoking article rod 2 when the smoking article rod 2 is inserted into the recess 30.

Figure 2 is a side-on cross sectional view of another example of an attachable unit 203 and a smoking article rod 2 which can be attached to form a smoking article 200. As with the previous example, the attachable unit 203 is arranged to be attached to the smoking article rod 2 by a user to modify one or more properties of aerosol generated by the smoking article rod 2. The attachable unit 203 comprises a cylindrical element 21 and a tubular element 31. The cylindrical element 21 and tubular element 31 are aligned on a common longitudinal axis (not shown) and connected together by a sheet material 22, in the present case wrapping at least a portion of the cylindrical element 21 and tubular element 31. The tubular element 31 defines a recess 30 which is arranged to receive at least a portion of the smoking article rod 2 when the attachable unit 203 is attached to the smoking article rod 2.

The smoking article rod 2 shown in Figure 2 is substantially the same as the smoking article rod 2 described in relation to Figure 1, and so detailed description of its structure is omitted. Furthermore, the dimensions of the recess 30 described with reference to Figure 1 also apply to the recess 30 illustrated in Figure 2. However, in the present example, the recess 30 is formed by the inner surface of the tubular element 31 together with the end surface 23 of the cylindrical element 21. The tubular element 31 is selected to have a manufacturing tolerance with regards to its internal diameter which is smaller than that achievable by the sheet material 22 of the example of Figure 1. For instance, the tubular element 31 can have an internal diameter of between 4mm and 10mm and a manufacturing tolerance for said internal diameter of +/- 0.1mm or less, +/- 0.05mm or less, +/- 0.04mm or less, +/- 0.03mm or less or +/- 0.02mm or less. Accordingly, the use of a tubular element 31 enables deviations in the diameter of the recess 30 to be reduced, facilitating insertion of the smoking article rod 2 into the recess 30 and minimising the variation in the distance between the outer surface of the portion of the smoking article rod 2 inserted into the recess 30 and the inner surface of the recess 30. The tubular element 31 may be made of a deformable material, such as a foamed material, rubber or a plastic material. This allows the tubular element 31 to deform when receiving the smoking article rod 2.

The attachable unit 3 may be attached to the smoking article rod 2 in any suitable way. This may include forming an interference fit between the inner surface of the tubular element 31 and the outer surface of the smoking article rod 2. In this case, the interference fit is such that a seal is formed at the interface between the inner surface of the tubular member 31 and the outer surface of the smoking article rod 2, which inhibits the ingress of gases (such as air) that would normally enter into the smoking article 200 via a gap between the outer surface of the smoking article rod 2 and the inner surface of the tubular member 31. The amount of air entering into a smoking article between two neighbouring surfaces may be variable and/ or unwanted.

Restricting the ingress of air therefore provides a degree of control of the airflow into and/or through the smoking article 200.

The attachable unit 203 can include additives or agents for modifying the aerosol, in the present case smoke, generated by the smoking article rod 2, in the same way as the attachable unit 3 described with reference to Figure 1 above.

In use, the smoking article 200 can be provided to users with the attachable unit 203 and smoking article rod 2 as separate components, for instance as a kit of parts. Prior to a user first using the smoking article 200, the attachable unit 203 can be attached to the smoking article rod 2 by inserting the smoking article rod 2 into the recess 30 of the attachable unit 203. When the attachable unit 203 is attached to the smoking article rod 2, the longitudinal end surface 23 of the cylindrical element 21 may abut the mouth end surface 16 of the filter 6. Alternatively, the attachable unit 203 may be attached to the smoking article rod 2 so that there is a gap between the longitudinal end surface 23 and the mouth end surface 16.

The user can select whether or not to attach the attachable unit 203 to the smoking article rod 2 prior to smoking the smoking article 200, and can in this way control the length of filter of the smoking article 200 and therefore the level of filtration of the aerosol generated by the smoking article 200, as well as other properties of the aerosol in the case that the attachable unit 203 includes one or more additives or agents for modifying the aerosol.

Figure 3 is a side-on cross sectional view of another example of an attachable unit 303 and a smoking article rod 302 which can be attached to form a smoking article 300.

Referring to Figure 3, the attachable unit 303 is arranged to be attached to a smoking article rod 302 by a user. The smoking article rod 302 in the present example comprises a first recess 13. As with the attachable units 3, 203 of Figures 1 and 2, the attachable unit 303 is configured to modify one or more properties of an aerosol generated by the smoking article rod 302. The attachable unit 303 includes an element 20 arranged to be inserted at least partially into the first recess 13 of the smoking article rod 302 and a second recess 330 to receive at least a portion of the smoking article rod 302. In the present example, the smoking article 300 is a cigarette and the smoking article rod 302 includes a tobacco rod 4 wrapped in a wrapping material 5, in this case cigarette paper. The smoking article rod 2 includes a filter 306 at its mouth end comprising a first section 7 located at the tobacco rod end of the filter 306. The first filter section 7 is, in the present example, formed from cellulose acetate tow wrapped in a first plug wrap 9. The filter 306 also includes a second section 10 located downstream of the first section 7 and comprising a tubular element 11 wrapped in a second plug wrap 12.

The tubular element 11 is, in the present example, open at the mouth end of the smoking article rod 302 and defines the first recess, or cavity, 13 at that end. A mouth end surface 316 of the tubular element 11 is exposed at the mouth end of the smoking article rod 302. The tubular element 11 can be formed from fibrous filtration material such as cellulose acetate having a relatively high plasticiser level, for instance between 15 and 21% by weight of the cellulose acetate. The tobacco rod 4 and first and second filter sections 7, 10 are connected by a tipping material 14 overlaying the first and second filter sections 7, 10 and partially overlaying the wrapping material 5. The first and second filter sections 7, 10, and any other sections forming the filter 306, can be connected together using a further plug wrap (not shown), prior to connection of the filter 306 to the tobacco rod 4 using the tipping material 14. The cylindrical element 20 of the attachable unit 303 is wrapped in a plug wrap 26 which is substantially impermeable to air, for instance having a permeability of greater than 50 Coresta Units or greater than 100 Coresta Units. However, the cylindrical element 20 may alternatively be unwrapped. The cylindrical element 20 of the attachable unit 303 has adjacent first and second portions 20a, 20b, each extending partially along the length of the cylindrical element 20. In the present example, the first portion 20a of the cylindrical element 20 extends from an insertion end of the cylindrical element 20 to an intermediate position 25 along the length of the cylindrical element 20. In the present example, the second portion 20b of the cylindrical element 20 extends from a mouth end of the cylindrical element 20 and ends at the intermediate position 25 along the length of the cylindrical element 20.

In the present example, the cylindrical element 20 is 25mm in length and the intermediate position 25 is 12.5mm along the length of the cylindrical element 20 from the insertion end. The first portion 20a of the cylindrical element 20 is arranged to be inserted, by a user, into the recess 13 at the mouth end of the smoking article rod 302.

The attachable unit 303 further comprises an annular element 27 which is arranged around the periphery of the second portion 20b of the cylindrical element 20. The annular element 27 has a larger external diameter than the internal diameter of the recess 13. The annular element 27 has a longitudinal end surface 29 which, together with the inner surface of the sheet material 22 and the outer surface of the cylindrical element 20, defines the second recess 303.

The longitudinal end surface 29 of the annular element 27 is arranged to face the smoking article rod 302 when the attachable unit 303 is attached to the smoking article rod 302. The longitudinal end surface 29 may abut the mouth end surface 316 of the tubular element 11 when the attachable unit 303 is attached to the smoking article rod 302, as described below. Additionally or alternatively, a longitudinal end surface 29' of the cylindrical element 20 may abut a mouth end surface 17 of the first filter section 7 when the attachable unit 303 is attached to the smoking article rod 302.

The first portion 20a of the cylindrical element 20 is arranged to be inserted into the first recess 13 in the smoking article rod 302, in the present case into the recess 13 formed by the tube section 11. The internal diameter and/or length of the recess 13 and the external diameter and/ or length of the first portion 20a of the cylindrical element 20 are arranged to substantially correspond such that the first portion 20a of the cylindrical element 20 can be received within and substantially fill the recess 13. For instance, the internal diameter of the recess 13 can be substantially the same as the external diameter of the first portion 20a of the cylindrical element 20. Furthermore, the length of the recess 13 can be substantially the same as the length of the first portion 20a of the cylindrical element 20 protruding proud of the annular element 27. In practice, the correspondence between the dimensions of the recess 13 and those of the first portion 20a of the cylindrical element 20 will depend on the materials used to form these components and the desired closeness of the fit between them. It is likely to be preferable that the recess dimensions are slightly larger than the dimensions of the first portion 20a, to facilitate insertion of the cylindrical element 20 into the recess 13.

In the example of Figure 3, the recess 13 has an internal diameter of 4mm and the cylindrical element 20 has an external diameter of 3.8mm. In alternative examples, the internal diameter of the recess 13 and external diameter of the cylindrical element 20 can have other values, for instance diameters in the range from 2mm to 6mm. In the example of Figure 3, the recess 13 has an internal length of 12mm and the first portion 20a of the cylindrical element 20 has a length of 12mm. In alternative examples, the internal length of the recess 13 and the length of the first portion 20a of the cylindrical element 20 can have other values, for instance values in the range from 5mm to 20mm.

In the present example, the annular element 27 is attached to the cylindrical element 20 using an adhesive (not shown). The annular element 27 may be attached to the cylindrical element 20 by means other than an adhesive, for example by mechanical means such as a friction fit or other locking arrangement.

The attachable unit 303 can include additives or agents for modifying the aerosol, in the present case smoke, generated by the smoking article rod 302, in the same way as the attachable unit 3 described with reference to Figure 1 above.

In use, the smoking article 300 can be provided to users with the attachable unit 303 and smoking article rod 302 as separate components. Prior to a user first using the smoking article rod 302, the attachable unit 303 can be attached to the smoking article rod 302 by inserting the first portion 20a of the cylindrical element 20 into the recess 13, so that the end portion of the smoking article rod 302 is received by the recess 330. When the attachable member 303 is attached to the smoking article rod 302, the longitudinal end surface 29 of the annular element 27 may abut the end surface 316 of the tubular element 11.

The user can select whether or not to attach the attachable unit 303 to the smoking article rod 302 prior to smoking the smoking article 300, and can in this way control the length of filter of the smoking article 300 and therefore the level of filtration of the aerosol generated by the smoking article 300, as well as other properties of the aerosol in the case that the attachable unit 303 includes one or more additives for modifying the aerosol.

In the present example, the annular element 27 and tubular element 11 comprise fibrous filtration material, formed into a tube and circumferentially wrapped in a wrapper 12 (not shown for annular element 27), in the present case plug wrap material, leaving the longitudinal ends unwrapped. In alternative embodiments the annular element 27 and/ or tubular element may be formed in other ways. For instance, the annular element 27 and/ or tubular element may alternatively be formed from other fibrous materials. The annular element 27 and/or tubular element also need not be wrapped in a wrapper, but could, for instance, be formed without a wrapper such as a non-wrapped acetate (NWA) tube formed from cellulose acetate fibres.

Figure 4 is a side-on cross sectional view of another example of an attachable unit 403 and a smoking article rod 302 which can be attached to form a smoking article 400. The smoking article rod 302 is the same as the smoking article rod described with reference to Figure 3 above. The attachable unit 403 is the same as the attachable unit 303 described above with reference to Figure 3 herein except that it also includes the tubular element 31 as described with reference to Figure 2 herein, arranged between the sheet material 22 and the first portion 20a of the cylindrical element 20, and attached to the sheet material 22. In addition, the tubular element 31 includes a raised area 50 on an inner surface thereof which defines the second recess 330, the raised area 50 being the same as that described with reference to Figure 1 herein.

The fibrous filtration material forming the tubes, and that forming other components of the attachable units 3, 203, 303, 403 and filter 6, 306 described herein may comprise cellulose acetate fibres and/ or other materials used to form fibres, such as polyvinyl alcohol (PVOH), polylactic acid (PLA), polycaprolactone (PCL), poly(i-4 butanediol succinate) (PBS), poly(butylene adipate-co-terephthalate)(PBAT), starch based materials, paper, cotton, aliphatic polyester materials and polysaccharide polymers or a combination thereof. The annular element 27 may alternatively be formed from a sheet material, such as tipping paper, wrapped around the cylindrical element 20 to form a single or multiple layers of the sheet material around the cylindrical element 20. The annular element 27 and/ or tubular element 11 may alternatively be formed from plastic or another moulded material.

The cylindrical element of any of the above examples may comprise fibrous filtration material. In alternative examples, the cylindrical element may be formed in other ways. The cylindrical element may alternatively be formed from other fibrous materials and can be arranged to have a different construction. The cylindrical element may, for instance, be formed from stiff paper, plastic, card or other materials as an open or closed ended hollow tube. The cylindrical element also need not be wrapped in a wrapper, but could, for instance, be formed without a wrapper such as a non-wrapped acetate (NWA) plug formed from cellulose acetate fibres. The fibrous filtration material may comprise cellulose acetate fibres and/or other materials used to form fibres, such as polyvinyl alcohol (PVOH), polylactic acid (PLA), polycaprolactone (PCL), poly(i-4 butanediol succinate) (PBS), poly(butylene adipate-co-terephthalate)(PBAT), starch based materials, paper, cotton, aliphatic polyester materials and polysaccharide polymers.

Filter plasticisers operate by softening the fibrous filter material from which a filter element is constructed such that the individual fibres can bond to each other to form a more rigid structure. A filter plasticiser such as glycerin triacetate, also referred to as triacetin, can, for instance, be used in the cylindrical element and/or annular element of any of the above examples when these elements are formed from a fibrous filtration material such as cellulose acetate. A higher level of plasticiser than is usually used in a filter element can be used to provide additional firmness to either component. For instance, greater than 7%, greater than 10%, greater than 12% or greater than 15% plasticiser can be used in any of the components described herein, by weight of the fibrous filtration material used. Any of the attachable units described above may include a flavour modifying agent or additive or flavour source. The flavour modifying agent may, for instance, be disposed in a cylindrical element of the attachable unit. For example, an attachable unit may be provided in which the cylindrical element comprises a frangible capsule containing a liquid payload comprising a flavourant, such as menthol. The user can squeeze the attachable unit to cause a pressure to be exerted on the capsule such that it breaks to release the flavourant contained therein, to thus modify aerosol drawn through the attachable unit. In other examples the attachable unit may comprise other flavour releasing components or flavour modifying agents. The features of the examples described herein can be combined. For instance, the raised area 50 of the example of Figure 1 can be applied to the inner surface of the tubular element 31 of the example of Figure 2, or to the inner surface of the sheet material 22 of the example of Figure 3, to perform an equivalent function as that described with reference to Figure 1. Also, the tubular element 31 of Figure 2 can be applied to the attachment unit 303 of Figure 3. In use, the smoking articles described herein can be provided to users with the attachable units described herein and smoking article rods described herein as separate components, for instance packaged separately or packaged together as a kit of parts for producing a smoking article.

A tubular filter component, such as the tubular element 11 described with reference to Figure 3, can be provided as an additional component at the mouth-end of any of the attachable units 3, 203, 303, 403 described herein.

In order to address various issues and advance the art, the entirety of this disclosure shows by way of illustration various embodiments in which the claimed invention(s) maybe practiced and provide for superior smoking articles and attachable units therefor. The advantages and features of the disclosure are of a representative sample of embodiments only, and are not exhaustive and/or exclusive. They are presented only to assist in understanding and teach the claimed features. It is to be understood that advantages, embodiments, examples, functions, features, structures, and/or other aspects of the disclosure are not to be considered limitations on the disclosure as defined by the claims or limitations on equivalents to the claims, and that other embodiments maybe utilised and modifications maybe made without departing from the scope and/ or spirit of the disclosure. Various embodiments may suitably comprise, consist of, or consist essentially of, various combinations of the disclosed elements, components, features, parts, steps, means, etc. In addition, the disclosure includes other inventions not presently claimed, but which may be claimed in future.