Method for Manufacturing Smoking Articles and Smoking Articles
The present invention relates to a method for making smoking articles, smoking articles, and more particularly to a method for manufacturing smoking articles having a reduced ignition propensity. A method of manufacturing a smoking article includes the steps of providing a filter element (40) and at least one rod (30) of smokeable material surrounded by a wrapper, wrapping a section of tipping paper (12A) around the filter element and a portion of the at least one wrapped rod and applying one or more patches (12B1, 12B2) of material to the outer surface of the wrapper. The patches can be arranged to reduce the ignition propensity of the smoking article and are applied to the outside of the wrapper, such that this can occur online during manufacture of the wrapped rod.
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The present invention relates to a method for making smoking articles, smoking articles, and more particularly to a method for manufacturing smoking articles having a reduced ignition propensity.
BACKGROUND TO THE INVENTIONMany different methods have been suggested for manufacturing smoking articles such as cigarettes having a reduced ignition propensity i.e. a tendency to self-extinguish when not drawn on by a smoker. Such smoking articles are generally referred to as having a low ignition propensity (LIP). It has been recognised that the constitution of the wrapper has a significant effect on the burn rate of a cigarette and by modifying the wrapper by various methods, a self-extinguishing cigarette can be produced.
One method for making wrappers for smoking articles having reduced ignition propensity is to add bands of paper to the wrapping paper, wherein the composition of the wrapper and the band paper are selected to yield a composite paper having the desired burn rate, as disclosed in EP 0 483998 and EP 0 262550. The bands are typically applied to the paper before it is wrapped around a tobacco core, and when the paper is wrapped around the tobacco the bands are on the inside of the paper, facing the tobacco. When the paper is used to manufacture the cigarettes, the bands are randomly situated along the length of the cigarette.
To ensure that cigarettes meet the requirements for self-extinguishment which exist in various counties, the accurate positioning of the bands along the length of the cigarette can be important. However, when using banded papers, ensuring that the bands are positioned in the correct positions along the cigarette is not straightforward and requires longitudinal registration of the paper, adding complexity to the cigarette manufacturing machinery.
Another method for making smoking articles having reduced ignition propensity is to apply a burn retardant additive to the smoking article wrapper, for instance cigarette paper. The burn retardant additive is typically applied as a solution in a pattern such as bands which, in the final assembled cigarette, extend around the circumference of the cigarette. A method for manufacturing a suitable such banded paper is disclosed in W 098/01233.
Attempts have been made to apply burn retardant additive banding during the cigarette making process. This allows the bands to be positioned at desired locations by synchronising the application of the bands with cutting of the rod formed when the tobacco is wrapped in the banded paper. This overcomes the problem of positioning of the bands found with the pre-manufactured banded papers. This on line application of banding is disclosed in WO 2004/057986 and US 2004/0261805. However, these processes have additional drawbacks. One problem is in the drying of the paper once the burn retardant solution has been applied. Firstly, this must be dried before the garniture section of the machine where the tobacco is wrapped in the paper, because if the paper is damp at this stage when it comes into contact with the tobacco then discolouration of the paper may occur. Furthermore, the machines used for wrapping cigarettes, which may be modified to include a section for applying a burn retardant solution, apply significant tension to the paper and when the paper is damp its tensile strength is significantly reduced so that tearing of the paper easily occurs. Various heaters can be included in the machine to assist in drying the paper but to allow time for these to properly dry the paper, the machine must be slowed. The slowing of the machine may also alleviate problems with tearing, but this decreases production efficiency.
SUMMARY OF THE INVENTIONThe present invention provides a method of manufacturing a smoking article comprising providing a filter element and at least one rod of smokeable material surrounded by a wrapper, wrapping a section of tipping paper around the filter element and a portion of the at least one wrapped rod and applying one or more patches of material to the outer surface of the wrapper.
The present invention also provides a smoking article comprising a rod of smokeable material surrounded by a wrapper, a filter element at one end of the wrapped rod, a tipping paper surrounding the filter element and a portion of the wrapped rod and a patch of material applied to the outer surface of the wrapper.
Therefore, one or more patches are applied to the outside of the wrapper, such that this can occur online during manufacture of the wrapped rod. This allows the position of the patches relative to the filter in the final smoking article to be determined.
The step of applying the one or more patches of material to the wrapper of the at least one wrapped rod can be performed in association with the step of wrapping the section of tipping paper around the filter element and an end of the at least one wrapped rod. In this way, modification to existing cigarette manufacturing processes in order to apply the additional patches can be minimised and production rates are not limited by the modification.
The one or more patches can comprise a low porosity or non porous web material and/or can comprise a web material having a permeability of approximately 50 CU or less, preferably approximately 10 CU or less. The one or more patches can be bands applied around the full circumference of the at least one wrapped rod, and/or applied such that the mouth-end side of the band is within the 50% of the length of the rod which is closest to the filter element.
The application of the bands can include applying a second band to each rod simultaneously to the application of the first band. The second band can be applied such that the mouth-end side of the second band is within the 50% of the length of the rod which is furthest from the filter element.
The step of providing a filter element and at least one rod of smokeable material surrounded by a wrapper can comprise providing first and second rods of smokeable material surrounded by wrappers, and a filter element interposed between the first and second rods, and the method can further comprise cutting the filter element to form two smoking articles after application of the one or more patches.
The method can also comprise splitting tipping paper from a roll to form both the patches and the section to be applied to the filter element and the ends of the wrapped rods.
The one or more bands can be spaced from an edge of the tipping paper and/or have a width of at least 4 mm. The material for the patches can be the same as the tipping paper material, although additional printing may be used on the section of material used on the tipping paper or bands.
The invention is defined in the claims appended hereto.
Preferred embodiments of the present invention will now be described with reference to the accompanying drawings, in which:
In accordance with standard cigarette manufacturing processes, a continuous wrapped rod of tobacco 20 is supplied from a garniture region of a cigarette making machine to cutting means 21A and 21B which cut the rod 20 into lengths required for a single cigarette. The first cutting means 21A cuts the rod 20 into double length rods, each having a length required to make two cigarettes, and then second cutting means 21B cuts the double length rods into single length rods 30. Each pair of single length rods 30 is separated and a double length filter 40 is positioned between the ends of the two wrapped rods 30 such that each end of the double length filter 40 abuts an end of one of the single length rods 30.
Tipping paper is supplied from a reel 13 of tipping paper mounted on a bobbin. In
The double length cigarette assembly is subsequently cut by third cutting means 50 at the centre of the double length filter 40 to form a cigarette pair.
In the method illustrated in
The cigarettes manufactured by the method illustrated in
Preferably, the first band A is positioned within the first 50% of the exposed length of the wrapped rod 1 ie (WA+a)/ LW≦0.5. Preferably, the second band B is spaced from the first band A and positioned within the last 50% of the exposed length of the wrapped rod 1 ie (LW−b)/ LW≦0.5. Preferably the width of the bands are approximately the same, i.e. WA=WB.
In the preferred example, given a cigarette of 83 mm length, wherein the length LT of the tipping paper 2 is 32 mm and the exposed length of the wrapped rod 1 LW is 51 mm, a=11 mm, b=31 mm and WA=WB=6 mm. The base material used for the LIP bands is the same as that used for the tipping paper (although different printing may be used on each section) and preferably has a porosity of approximately 5 Coresta Units (CU).
In an alternative to the embodiment shown in
As would be appreciated by those skilled in the art, the specific values chosen for the widths WA, WB and sizes of the LIP patches, for the porosity of the LIP patches and for their position on the wrapped rod can be adjusted as appropriate to achieve a required reduction in ignition propensity and the location at which this will be effective. For example, LIP band widths above approximately 4 mm could be used, preferably between 4 mm and 25 mm and more preferably between approximately 4 mm and 10 mm. The porosity of the paper can be less than approximately 50 CU, preferably less than 10 CU and more preferably less than or equal to 5 CU.
In a particular example, based on LIP performance measured according to the ASTM E2187-04 method, LIP-compliant cigarettes were manufactured having a single 5 CU porosity LIP band applied per cigarette in a 6 mm or 8 mm width and with the mouth-end edge of the band being 50 mm from the mouth end of the cigarette. The banding material was adhered to the tobacco rod with water-based glue.
The width of the LIP patch 12B1, 12B2 may optionally be substantially equal to the length LW of the region of wrapped tobacco rod 30 which is not covered by the sheet of tipping paper 2 connecting the wrapped rod 30 to the filter. For example,
The regions of the patch C between the windows 3 fully circumscribe the wrapped tobacco rod 30. Therefore, the regions of the patch which do not align with a window 3 can be considered as corresponding to the LIP bands A, B described above. The patch C thus provides the same LIP effect as the LIP patches A, B previously referred to. Specifically, burning of the wrapped tobacco rod 30 is hindered in the regions of the rod 30 which are covered by the LIP patch A, B, C whilst burning of the rod 30 is less hindered in the regions of the rod 30 which are not covered by the patch A, B, C. The rate of gaseous transfer between the tobacco and the surrounding environment, for example the surrounding air, through the windows 3 in the patch C mirrors the rate of gaseous transfer through the un-banded regions of the wrapped rod 30 shown in
The location of the windows 3 may be opposite to the location of the LIP bands A, B described above. For example, as shown in
Therefore, circumferential regions of LIP material are provided around the same regions of the wrapped tobacco rod 30 in both the embodiment shown in
The location, number and size of the windows in the patch C can be chosen in accordance with the desired LIP effect. Optionally, windows 3 may be provided in a circumferential band around the tobacco rod 30 so that two or more windows 3 are provided at the same longitudinal location on the rod 30. The windows 3 can be of any suitable shape.
If the LIP patch material comprises the same material that is used for the tipping paper 2, a sheet of the material can optionally be applied over the whole length of a double length cigarette of the type shown in
In
Claims
1. A method of manufacturing a smoking article comprising:
- providing a filter element and at least one rod of smokeable material surrounded by a wrapper;
- wrapping a section of tipping paper around the filter element and a portion of the at least one wrapped rod; and
- applying one or more patches of material to the outer surface of the wrapper;
- wherein applying the one or more patches of material to the wrapper of the at least one wrapped rod is performed in association with wrapping the section of tipping paper around the filter element and an end of the at least one wrapped rod.
2. (canceled)
3. The method according to claim 1,
- wherein the one or more patches comprise one of a low porosity and non porous web material.
4. The method according to claim 1,
- wherein the one or more patches comprise a web material having a permeability of about 50 CU or less.
5. A method of manufacturing a smoking article comprising:
- providing a filter element and at least one rod of smokeable material surrounded by a wrapper;
- wrapping a section of tipping paper around the filter element and a portion of the at least one wrapped rod; and
- applying one or more patches of material to the outer surface of the wrapper;
- wherein the one or more patches are bands applied around the full circumference of the at least one wrapped rod; and
- wherein each band is applied such that the mouth-end side of the band is within the 50% of the length of the rod which is closest to the filter element.
6. (canceled)
7. The method according to claim 5,
- wherein the application includes applying a second band to each rod simultaneously to the application of the first band.
8. A method of manufacturing a smoking article comprising:
- providing a filter element and at least one rod of smokeable material surrounded by a wrapper;
- wrapping a section of tipping paper around the filter element and a portion of the at least one wrapped rod; and
- applying one or more patches of material to the outer surface of the wrapper;
- wherein the one or more patches are bands applied around the full circumference of the at least one wrapped rod;
- wherein the application includes applying a second band to each rod simultaneously to the application of the first band; and
- wherein the second band is applied such that the mouth-end side of the second band is within the 50% of the length of the rod which is furthest from the filter element.
9. A method of manufacturing a smoking article comprising:
- providing a filter element and at least one rod of smokeable material surrounded by a wrapper;
- wrapping a section of tipping paper around the filter element and a portion of the at least one wrapped rod; and
- applying at least one patch of material to the outer surface of the wrapper;
- wherein the at least one patch comprises a patch having a window which exposes a region of the outer surface of the wrapper.
10. The method according to claim 9,
- wherein said at least one patch comprises a plurality of said windows.
11. The method according to claim 9,
- wherein said patch extends substantially from an edge of the tipping paper to an end of the rod of smokeable material which is furthest from the filter.
12. The method according to claim 1,
- wherein the providing comprises first and second rods of smokeable material surrounded by wrappers, and the filter element interposed between the first and second rods, and
- wherein the method further comprises cutting the filter element to form two smoking articles after application of the one or more patches.
13. A method of manufacturing a smoking article comprising:
- providing a filter element and at least one rod of smokeable material surrounded by a wrapper;
- splitting tipping paper from a roll to form patches, and a section to be applied to around the filter element and a portion of the at least one wrapped rod;
- wrapping the section of tipping paper around the filter element and the portion of the at least one wrapped rod; and
- applying one or more patches of material to the outer surface of the wrapper.
14. A smoking article comprising:
- a rod of smokeable material surrounded by a wrapper;
- a filter element at one end of the wrapped rod;
- a tipping paper surrounding the filter element and a portion of the wrapped rod; and
- a patch of material applied to the outer surface of the wrapper;
- wherein the patch comprises a window which exposes a region of the outer surface of the wrapper.
15. The smoking article according to claim 14,
- wherein the patch comprises one of a low porosity and non porous web material.
16. The smoking article according to claim 15,
- wherein the patch comprises a web material having a permeability of about 50 CU or less.
17. The smoking article according to claim 14,
- wherein the patch is a band applied around the full circumference of the wrapped rod.
18. The smoking article according to claim 17,
- wherein the band is spaced from an edge of the tipping paper.
19. The smoking article according to claim 17,
- wherein the band is at least 4 mm wide.
20. The smoking article according to claim 19,
- wherein the band is at least 6 mm wide.
21. (canceled)
22. The smoking article according to claim 14,
- wherein the patch comprises a plurality of said windows.
23. A smoking article comprising:
- a rod of smokeable material surrounded by a wrapper;
- a filter element at one end of the wrapped rod;
- a tipping paper surrounding the filter element and a portion of the wrapped rod; and
- a patch of material applied to the outer surface of the wrapper; wherein the patch is a band at least 4 mm wide applied around the full circumference of the wrapped rod; and wherein the patch extends substantially from an edge of the tipping paper to an end of the rod of smokeable material which is furthest from the filter.
24. A smoking article comprising:
- a rod of smokeable material surrounded by a wrapper;
- a filter element at one end of the wrapped rod;
- a tipping paper surrounding the filter element and a portion of the wrapped rod; and
- a patch of material applied to the outer surface of the wrapper;
- wherein the material is the same as the tipping paper.
Type: Application
Filed: Mar 31, 2011
Publication Date: May 16, 2013
Applicant: BRITISH AMERICAN TOBACCO (INVESTMENTS) LIMITED (London)
Inventors: Karl Kaljura (London), Leonardo Nappi (London), Richard Fiebelkorn (London)
Application Number: 13/642,457
International Classification: A24D 1/02 (20060101);