Description

The present invention relates to a smoking article having a filter and, more particularly, to a smoking article having a filter with a window portion therein, and a method of producing die same.

Conventionally, smoking articles such as cigarettes comprise a tobacco rod in the form of a cylinder of tobacco or tobacco-based smokeable material wrapped in a paper wrapper, which may be provided with a filter unit. In its basic form, the filter unit is a cylindrical element formed from filtration material such as acetate tow, optionally including features to modify the smoke flow and filter function, such as recesses and gaps, and additives such as particulate carbon. The tow may be wrapped in a layer of plug wrap which helps maintain the cylindrical shape and structure of the filtration material. The filter unit is joined to the tobacco rod using a tipping paper, which is an outer paper layer wrapped around the filter unit and overlapping the join between the filter unit and tobacco rod. The tipping paper is glued in place.

Various forms of smoking articles including filters are known, for example, WO

2004/068975 describes a smoking article having a filter wherein the filter comprises a pair of discrete plugs of filter material wrapped with a transparent plug wrap and, a tipping paper attaching a tobacco rod to the filter. The tipping wrapper is formed from discrete sections of opaque paper disposed either side of a discrete section of transparent material, which are bonded together to form die tipping wrapper. The filter of this known smoking article thereby includes a window formed by the transparent material to allow the a space between the filter segments to be visible.

However, die above prior art filter suffers the disadvantage that die complex construction of the tipping paper formed from discrete sections of material bonded together, means that manufacture is more complicated and time consuming, and thereby costly. A fuitliei known smoking aiticle is disclosed in US 2002/0153017 and conipiises a tobacco iod having a filtei attached to one end theieof The filter compiises a plmakty of plugs of filtei mateiial wiapped with a transparent plug wiap The filtei is attached to the tobacco iod with a tipping wrapper, which may include one oi more windows formed theiein to enable die filter material to be visible However, tins pnor ait suffers die disadvantage that die tipping wiappei must be provided with pie-foimed holes for die windows, or else, an additional manufacturing step is requited to foim disciete holes m die tipping wiappei prior to it being applied to the smoking article In eithei case, die tipping wrappei construction is complex and/or die manufacturing process is complex, thereby mcieasmg manufacturing costs

Accordingly, die piesent invention seeks to provide a smoking aiticle having a filter which substantially alleviates or overcomes die problems mentioned above

The piesent invention piovldes a smoking aiticle comprising a iod of smokeable mateiial and, a filtei attached to one end of the iod, said filtei compiisiiig an elongate body of filtei mateiial wiapped with a tianspaient plug wiap, wheiem a fust tipping wiappei oveilles the _j oin between the iod and the filtei to attach the filtei to the iod, and at least one additional tipping wiappei is piovided aiound the filtei, spaced fiom and sepaiate to the fust tipping wiappei such that a poition of the tianspaient plug wiap is exposed between the fust and at least one additional tipping wiappei to define a window poition thiough which the filtei mateiial is visible

Two additional tipping wiappeis may be wiapped aiound the filtei spaced fiom and sepaiate to the fust tipping wiappei and each othei, such that a poition of the tianspaient plug wiap is exposed between each tipping wiappei to define two disciete window poitions thiough which the filtei mateiial is visible

The body of filtei mateiial may compiise a pluiahty of filtei sections wiapped in said tianspaient plug wiap and at least one of the filtei sections may have diffeimg filtering characteristics to the or each other filter section(s)

Two of the filter sections may be spaced from each other to define a cavity therebetween m the filter.

At least one of the filter sections may be wrapped m its own inner plug wrap underneath said transparent plug wrap and the at least one inner plug wrap may also be transparent.

At least one thread may extend at least partially through the filter and the at least one thread may be disposed adjacent the transparent plug wrap and be visible through the window portion.

The present invention also provides a method of manufacturing a smoking article comprising providing a filter formed of an elongate body of filter material wrapped with a transparent plug wrap, attaching a rod of smokeable material to one end of the filtei by wrapping a first tipping wrapper around the filter and the rod such that it overlies the join between the filter and the rod and, wrapping at least one additional tipping wrapper around the filter, spaced from and separate to the first tipping wiapper, such that a portion of the transparent plug wrap is exposed between the first and at least one additional tipping wrapper to define a window portion through which the filter material is visible.

The step of wrapping the first tipping wrapper around the filter and rod and the step of wiappmg the at least one additional tipping wrapper around the filter, may be peifoimed simultaneously.

The method may comprise feeding the first tipping wiapper and the at least one additional tipping wiappei fiom sepaiate reels of tipping wrappei mateiial The method may also compiise cutting each tipping wrappei to length as they aie fed fiom then lcspective reels. Alternatively, the method may comprise feeding a single band of tipping wrapper material from a single reel to at least one cutting element and cutting the single band of tipping wrapper material as it passes the at least one cutting element to form the first tipping wrapper and the at least one additional tipping wrapper. The method may also comprise cutting each tipping wrapper to length after they have passed the cutting element(s).

The method may comprise applying glue to the tipping wrappers prior to wrapping around the filter/rod to attach the tipping wrappers to the filter and/or rod.

The method may further comprise attaching a second rod of smokeable material to the other end of the filter by wrapping another tipping wrapper around the other end of the filter and the second rod such that it overlies the join between the other end of the filter and the second rod, said another tipping wrapper being spaced from and separate to said at least one additional tipping wrapper, such that a portion of the transparent plug wrap is exposed between said another tipping wrapper and said at least one additional tipping wrapper to define a window portion through which the filter material is visible, and cutting the filter at its middle point to create two separate smoking articles.

The method may comprising initially wrapping an elongate body of filter material with a transparent plug wrap to form said filter.

In order that the invention may be more fully understand, embodiments of die invention will be described, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 shows a perspective view of a smoking article according to a first embodiment of the invention; Figure 2 shows an exploded perspective view of the smoking article of Figure 1; Figure 3 shows a perspective view of a smoking article according to a second embodiment of the invention; Figure 4 shows an exploded perspective view of the smoking article of Figure 3; Figuϊe 5 shows a perspective view of a smoking article according to a third embodiment of the invention;

Figure 6 shows an exploded perspective view of a smoking article Figure 5; Figures 7a to 7c schematically show steps of a first manufacturing process according to the invention to produce a smoking article as shown in Figures 1 and 2; and

Figures 8a to 8c schematically show steps of a second, alternative manufacturing process according to the invention to produce a smoking article as shown in Figures 1 and 2.

Referring now to Figures 1 and 2, a smoking article 10 according to a first embodiment of the invention is shown comprising a tobacco rod 12 and a filter 14. The tobacco rod 12 comprises a cylinder of smokeable tobacco or tobacco-based material contained within a paper sleeve.

The filter 14 comprises a cylindrical plug of filter material 16 such as cellulose acetate tow, wrapped with a plug wrap 18 which serves to contain die loose filter material in the cylindrical form of the filter. The plug wrap 18 is made of a transparent material such that the filter material 16 is visible through the plug wrap 18. The term 'transparent used herein is intended to refer to any material which is fully or partially see-through. This is, for instance, regardless of colour, so that clear, tinted, or otherwise 'translucent' materials are deemed to be 'transparent'.

The filter 14 is attached to die tobacco rod 12 by a first tipping wrapper 20a which is wrapped around die tobacco rod 12 and die filter 14 and overlies die join therebetween. The tipping wrapper includes an adhesive to bond it to die filter 14 and tobacco rod 12.

A second, separate tipping wrapper 20b is wrapped around die mouth end of die filter 14 distal to die tobacco rod 12 end of the filter 14, and is spaced from die first tipping wrapper 20a to leave a gap G therebetween. The transparent plug wrap 18 is exposed in the gap G to define a window portion 22 in the filter section of die smoking article 10. The filter material 16 is thereby visible though the window 22. Furthermore, die above- desciibed smoking article 12 having the window 22 in the filter section is simply and cheaply produced without use of a complex ripping-wrapper configuration having punched holes or separate pre-bonded sections, or a complex tipping wrapper manufacturing stage.

A smoking article 30 of a second embodiment of the invention is shown in Figures 3 and 4, and comprises a tobacco rod 32 and a filter 34. The tobacco rod 32 comprises a cylinder of smokeable tobacco or tobacco-based material contained within a paper sleeve.

As with the smoking article 12 of the first embodiment described above, the filter 34 comprises a cylindrical plug of filter material 36 such as cellulose acetate wrapped with a plug wrap 38 which serves to contain the loose filter material in the cylindrical form of the filter. The plug wrap 38 is made of a transparent material such that the filter material 36 is visible through the plug wrap 38.

The filter 34 is attached to the tobacco rod 32 by a first tipping wrapper 40a which is wrapped around die tobacco rod 32 and the filter 34 and overlies the join therebetween, and includes an adhesive to bond it to the filter 34 and tobacco rod 32.

A second, separate tipping wrapper 40b is wrapped around die mouth end of the filter 34 distal to die tobacco rod 32 end of the filter 34, and is spaced from the first tipping wrapper 40a. However, the smoking article 30 of the second embodiment differs from die smoking article 10 of die first embodiment, in that a third tipping wrapper 40c is wrapped around die filter 34 between and spaced from die first and second tipping wrappers 40a, 40b. Thereby, a first gap Gl is left between die first tipping wrapper 40a and the third tipping wrapper 40c, and a second gap G2 is left between the third tipping wrapper 40c and the second tipping wrapper 40b.

The transparent plug wrap 18 is exposed in the gaps Gl, G2 to define a pair of window portions 42a, 42b in die filter section of the smoking article 32. The filter material 36 is dius visible though the two windows 42. A smoking article 50 of a third embodiment of the present invention is shown in Figures 5 and 6 and comprises a tobacco rod 52 and a filter 54. The tobacco rod 52 comprises a cylinder of smokeable tobacco or tobacco-based material contained within a paper sleeve.

The smoking article 50 of the third embodiment of the invention differs from smoking articles 10, 30 of the first and second embodiments, in that die filter 54 does not comprise a single elongate plug of filter material, but instead, comprises diree separate filter sections of cylindrical plugs of filter material 56a, 56b, 56c. Each individual plug of filter material 56a, 56b, 56c may be the same, such as cellulose acetate, or each may differ from the others, for example, one may be cellulose acetate impregnated with activated charcoal particles. The individual plugs of filter material 56a, 56b, 56c may also be of different colours. In order that each individual plug of filter material 56a, 56b, 56c can be kept in its desired cylindrical form during the manufacturing process, each is wrapped in an individual plug wrap 57a, 57b, 57c.

Once collated together side by side, the three individually wrapped plugs of filter material 56a, 56b, 56c are dien wrapped together with an single outer plug wrap 58 which holds them together as one unit. The outer plug wrap 58 is made of a transparent material such that the individual wrapped cylindrical filter plugs 56a, 56b, 56c are visible through the outer plug wrap 58.

In order that the filter material 56a, 56b, 56c of each individual plug can be visible through die outer plug wrap 58, one or more of the individual plug wraps 57a, 57b, 57c may also be made from a transparent material.

As with die previously-described embodiments, the filter 54 is attached to the tobacco rod 52 by a first tipping wrapper 60a which includes an adhesive on one side and is wrapped around die tobacco rod 52 and die filter 54 and overlies die join therebetween. A second, separate ripping wrapper 60b is wrapped around the mouth end of die filter 54 distal to the tobacco rod 52, and is spaced from the first tipping wrapper 60a to leave a gap G therebetween. The transparent outer plug wrap 58 is exposed in the gap G to define a window portion 62 in die filter section of the smoking article 52. The individual plug wraps 57a, 57b, 57c wrapped around the individual plugs of filter material 56a, 56b, 56c are therefore visible though the window 62. Furthermore, if the individual plug wraps 57a, 57b, 57c which are visible though the window 62 are also of a transparent material, then the individual plugs of filter material 56a, 56b, 56c are therefore visible though the window 62.

In the third embodiment of the invention described above, the filter 54 is described as comprising three separate plugs of filter material 56a, 56b, 56c. However, it will be appreciated that two or more than three may be provided within the scope of die invention. Furthermore, the invention is not intended to be limited to each individual plug of filter material 56a, 56b, 56c being first wrapped in its own individual plug wrap 57a, 57b, 57c, and instead, die outer plug wrap 58 may serve to hold all three plugs of filter material together and in the cylindrical form. The first and second tipping wrappers 60a, 60b may be sized and aligned to expose only die middle cylindrical plug of filter material 56b in the window 62. Alternatively, die first and second tipping wrappers 60a, 60b may be arranged to expose parts of die first and third cylindrical plugs of filter material 56a, 56c in the window 62. In a further alternative of die third embodiment, the middle plug could be omitted to create a cavity within the filter 54 which would be visible through die window 62. The cavity could be an empty air-filled space, or could be filled with some further smoke modification material, for example, an adsorbent such as carbon granules, or a flavourant such as loose mint leaf. Yet further, the filter could include one or more threads extending therethrough, and such diread(s) could be visible in die cavity tiirough the window 62.

Variations are possible from the above described smoking articles 10, 30, 50 within die scope of the invention. For example, more than three separate tipping wrappers may be provided circumscribing die filter and/or tobacco rod and spaced from each other, thereby providing more than two separate window portions. The filter may comprise various filter materials, such as paper or other cellulose acetate-based materials, in addition to or in place of cellulose acetate. Furthermore, the filter material may include additional additives such as particulate activated charcoal to aid filtration properties. The filter material 16/36/56 may also include one or more grooves formed around its outer edge and visible through the transparent plug wrap 18/38/58, and thereby visible through the window 22/42a,b/62. The filter material 16/36/56 may also include one or more threads of, for example, cotton or cellulose acetate, formed around its outer edge and visible through the transparent plug wrap 18/38/58, and thereby visible through die window 22/42a,b/62. Such thread(s) may extend partially or fully though the length of the filter. It will thus be appreciated that the smoking article comprising the window portions in the embodiments described and any variations thereof are clearly visually distinctive from conventional smoking articles.

A first method of manufacturing the a smoking article according to the first embodiment of the invention will now be described with reference to Figures 6a to 6c. In Figure 6a, two tobacco rods 12 are aligned with a double length filter 14 between them and in abutment with each other. (The process of producing and cutting to lengdi of the tobacco rods 12 is as known in the art, and so a detailed description of this process will not be described). The double length filter 14 comprises a cylindrical plug of filter material wrapped with a transparent plug wrap. Three separate reels of tipping wrapper paper are provided, a first central reel 70a, and two outer reels 70b, 70c, one either side of die central reel 70a. The central reel 70a is approximately twice the width of the two outer reels 70b, 70c, but is not as wide as the double length filter 14 is long.

The central reel 70a of tipping wrapper is fed out and is wrapped around the middle of the double lengdi filter 14, and the two outer reels 70b, 70c of tipping wrapper are fed out and one is wrapped around each end of the double length filter 14 and around the adjacent end of die respective tobacco rod 12, to overlie die join therebetween and secure die respective tobacco rod 12 to die respective end of the double length filter 14. The tipping wrappers are then cut from their respective reels 70a, 70b, 70c resulting in a double-lengdi smoking article as shown in Figure 6b. A cutter 72 cuts the double length smoking article at the middle of the double length filter 14, to produce two separate smoking articles 10, as shown in Figure 6c, and shown and described previously with respect to Figures 1 and 2. It will thus be appreciated diat the first ripping wrapper 20a of the resulting smoking article 10 is provided by the tipping wrapper from one of die outer tipping wrapper reels 70b, 70c, and die second tipping wrapper 20b at die mouth end of die resulting smoking article 10 is provided by die tipping wrapper from die central tipping wrapper reel 70a after the cutter 72 separates die two smoking articles 10.

It will be apparent from the above tiiat die method of producing die smoking article 10 having a window portion 22 in die filter section 14 is much simplified over known prior art processes and so manufacturing costs are greatly reduced. The size of die window portion 22 in die resulting smoking article can be determined by selection of tipping wrapper paper reel widths and spacing of die tipping wrapper reels from each odier.

A second, alternative mediod of manufacturing a smoking article 10 according to die first embodiment of die invention will now be described witii reference to Figures 7a to 7c. In Figure 7a, as witii the first method described above, two tobacco rods 12 are aligned with a double lengdi filter 14 between them and in abutment witii each other. The double lengdi filter 14 comprises a cylindrical plug of filter material 16 wrapped widi a transparent plug wrap 18. The alternative method differs from the first method described previously in that instead of there being diree separate reels of tipping wrapper paper 70a, 70b, 70c, there is only single wide reel of tipping wrapper paper 80. However, a pair of cutting blades 84 (which may be blades, cutting wheels, or any other suitable cutting elements) are disposed between die wide reel of tipping paper 80 and die filter 14/ tobacco rods 12. As die tipping paper is fed from die wide reel 80 towards die filter 14/tobacco rods 12, it passes over die cutting blades 84 and is diereby cut into three separate bands of tipping wrapper, a central tipping wrapper band 86a, and two outer tipping wrapper bands 86b, 86c.

The central tipping wrapper band 86a is fed to be wrapped around die middle of die double length filter 14, and die two outer tipping wrapper bands 86b, 86c are fed so that one is wrapped around each end of the double lengdi filter 14 and around the adjacent end of die respective tobacco rod 12, to overlie die join dierebetween and secure die respective tobacco rod 12 to die respective end of the double length filter 14. The diree tipping wrapper bands 86a, 86b, 86c are dien cut from the rest of die bands, resulting in a double-lengdi smoking article as shown in Figure 7b.

As with the first metiiod described previously, a cutter 82 dien cuts die double lengdi smoking article at die middle of die double lengdi filter 14, to produce two separate smoking articles 10, as shown in Figure 7c, and shown and described previously with respect to Figures 1 and 2. It will thus be appreciated diat die first tipping wrapper 20a of die resulting smoking article 10 is provided by one of die outer tipping wrapper bands 86b, 86c and the second tipping wrapper 20b at die moudi end of the filter 14 of die resulting smoking article 10 is provided by the central tipping wrapper band 86a after die cutter 82 separates die two smoking articles 10.

It will be apparent from die above that die alternative mediod of producing die smoking article 10 having a window portion 22 in die filter section 14 is also much simplified over known prior art processes and so manufacturing costs are gready reduced. The size and position of die window portion 22 in die resulting smoking article can be determined by selection of tipping wrapper paper reel 80 width, die position of die two cutting blades 84 relative to the tipping wrapper reel 80 and die position diat die diree bands of tipping wrappers 86a, 86b, 86c are fed to.

In order to manufacture a smoking article 30 according to a second embodiment of die invention using die first method described above, diere could be five separate reels of tipping wrapper, a central wider reel and two narrower reels each side of die central reel. The central reel would provide tipping wrapper around die middle of the double lengdi filter, die outermost two reels would provide tipping wrappers around and overlying die join between the double length filter and the respective tobacco rod, and the remaining two tipping wrapper reels between the central reel and die outermost reels would provide a tipping wrapper around die double lengdi filter between the central tipping wrapper and die outer tipping wrappers. Thereby, when die cutter 72 cuts die double smoking article in die middle, it would produce two smoking articles 30 as shown in Figure 3.

In order to manufacture a smoking article 30 according to a second embodiment of die invention using the second, alternative method described above, tiiere could be four cutting blades instead of just two, such that die single wide reel of tipping wrapper paper is tiien cut into five bands, a central wider band, and two narrower bands on each side of die central band. The central band of tipping wrapper would be provided around die middle of die double lengdi filter, the outermost two bands of tipping wrapper would be provided around and overlying die join between die double length filter and the respective tobacco rod, and die remaining two bands of tipping wrapper between the central band and die outermost bands would be wrapped around die double lengdi filter between the central tipping wrapper band and die outer tipping wrapper bands. Thereby, when the cutter 82 cuts die double smoking article in die middle, it would produce two smoking articles 30 as shown in Figure 3.

In order to manufacture a smoking article 50 according to a tiiird embodiment of die invention using either of die above described metiiods, it would simply be necessary to provide an alternative filter unit comprising a plurality of separate filter plugs, wrapped in die outer transparent plug wrap, in place of die single double length filter. From diat point onwards, die manufacturing processes would be die same as described above.

Furthermore, die variations of the two methods described above (i.e. having more dian three separate tipping wrapper reels, or more than two cutters to produce more dian three separate tipping wrapper bands) could be implemented to provide a plurality of windows in the multi-section filter portion of die smoking article, as opposed to just die one window as illustrated in Figure 1.

In order that the tipping wrappers adhere to die filter and tobacco rods, they are provided with glue prior to being wrapped around die filter/ tobacco rod. The glue may be prc-applied to die tipping wrapper material during manufacture thereof, or alternatively, may be applied at a point between the tipping wrapper material being fed from the or each reel, and being wrapped around the filter/ tobacco rods.

Although the above-desciibed methods compiise foimmg two smoking articles at a time by attaching tobacco rods to opposite ends of a double length filter and cutting the filter in die middle, it will be appreciated that the invention is not limited to such a method and the smoking aiticles may alternatively be produced individually by a single filter being attached to a single tobacco rod by a first tipping wrapper and then one or more tipping wrappers being wrapped around the filter, separate to and spaced from the first tipping wrapper.

In die above described embodiments, the tipping wrappers comprise bands of paper, such diat die tactile sensation for die smoker corresponds to die feeling of regular paper-tipped smoking articles. In particular, it is therefore advantageous for die tipping wrapper at die mouth-end of die filter to be made from paper.

The plug-wraps are described in die above embodiments as being made from a transparent material. Such materials may include, but are not limited to, one of polypropylene, polyvinyl chloride (PVC), cellulose acetate film, polyethylene terephthalate (PET), polyethylene oxide (PEOX), polyethylene, cellophane, Natuiefiex ^1M oi polyactic acid (PLA). In addition to die plug wrap being totally transparent and clear, it could also be colouied transparent ('translucent'), oi include fuither patterns, maikings, logos oi othei giaphics oi indicia punted theieon.

Although vaiious embodiments of the smoking article and manufactuiing mediod of the piesent invention have been described above, the scope of the invention is not intended to be limited to diese examples and any combination of non-mutually exclusive featuies desciibed above is also intended to fall within the scope of the invention, defined by the claims hereaftei