PAPER CAVITY FILTER

Abstract

A tobacco smoke filter or filter element comprising: a longitudinally extending core which includes a paper or other non-cellulose acetate containing filtering material and a wrapper engaged around the longitudinally extending core wherein the filter or filter element is readily biodegradable and wherein; the longitudinally extending core includes two plugs of paper or other non-cellulose acetate containing filtering material distanced longitudinally from each other and the wrapper engaged around the plugs of paper or other non-cellulose acetate containing filtering material defines a cavity between the plugs of paper or other non-cellulose acetate containing filtering material; and/or at least one end of the wrapper extends beyond the end of the longitudinally extending core around which is engaged to define a cavity or recess at the end of the filter.

Claims

1. A tobacco smoke filter or filter element comprising: a longitudinally extending core which includes a paper or other non-cellulose acetate containing filtering material and a wrapper engaged around the longitudinally extending core, wherein the filter or filter element is readily biodegradable and wherein: (a) the paper or other non-cellulose acetate containing filtering material comprises two plugs of paper or other non-cellulose acetate containing filtering material distanced longitudinally from each other and the wrapper engaged around the plugs of paper or other non-cellulose acetate containing filtering material defines a cavity between the plugs of paper or other non-cellulose acetate containing filtering material; and/or (b) at least one end of the wrapper extends beyond an end of the longitudinally extending core to define a cavity or recess at an end of the filter or filter element.

2-4. (canceled)

5. The tobacco smoke filter or filter element according to claim 1, wherein the filter or filter element has ‘Ready Biodegradability’ level of biodegradability as measured according to OECD 301B ‘Ready Biodegradability’ method (modified Sturm test).

6-9. (canceled)

10. The tobacco smoke filter or filter element according to claim 1, wherein the further wrapper extends beyond the end of the core engaged by a length of 3 to 14 mm.

11. The tobacco smoke filter or filter element according to claim 1, wherein both ends of the further wrapper extend beyond the end of the core to define a cavity or recess at each end of the filter or filter element.

12. The tobacco smoke filter or filter element according to claim 11, wherein both ends of the further wrapper extend beyond the end of the core by a length of 3 to 14 mm.

13. The tobacco smoke filter or filter element according to claim 1, wherein a first end of the further wrapper extends beyond a first end of the core, to define a cavity or recess at the end of the filter or filter element; and a second end of the further wrapper is flush or substantially flush with second end of the core.

14. The tobacco smoke filter or filter element according to claim 1, wherein the cavity between the plugs of wrapped paper or other non-cellulose acetate containing filtering material is of length 3.5 mm to 32.

15. The tobacco smoke filter or filter element according to claim 1, which is of length to 45 mm, and/or which is of perimeter or circumference 14 to 28 mm.

16. (canceled)

17. The tobacco smoke filter or filter element according to claim 1, wherein the longitudinally extending core is of length 7 to 30 mm and/or the longitudinally extending core is a substantially cylindrical core.

18. The tobacco smoke filter or filter element according to claim 1, wherein the paper or other non-cellulose acetate containing filtering material is wrapped in a paper.

19. The tobacco smoke filter or filter element according to claim 18, wherein the paper is of basis weight from about 27 to about 80 g/m.sup.2.

20. The tobacco smoke filter or filter element according to claim 1, wherein the further wrapper is paper.

21. The tobacco smoke filter or filter element according to claim 20, wherein the further wrapper is paper of basis weight from about 27 to about 120 g/m.sup.2.

22. The tobacco smoke filter or filter element according to claim 1, wherein the further wrapper is a stiff paper tube.

23. The tobacco smoke filter or filter element according to claim 1, comprising an outer wrapper.

24. The tobacco smoke filter or filter element according to claim 1, wherein the paper or other non-cellulose acetate containing filtering material is paper.

25. The tobacco smoke filter or filter element according to claim 1, wherein the paper or other non-cellulose acetate containing filtering material is a natural fibre.

26. The tobacco smoke filter or filter element according to claim 1, wherein the paper or other non-cellulose acetate containing filtering material comprises a blend of different paper or other non-cellulose acetate containing filtering materials.

27. The tobacco smoke filter or filter element according to claim 1, which comprises one or more further plugs of filtering material.

28. The tobacco smoke filter or filter element according to claim 1, wherein the plugs of paper filtering material are comprised of different paper filtering materials.

29. (canceled)

30. The tobacco smoke filter or filter element according to claim 1, which further comprises a capsule or capsules.

31. (canceled)

32. The tobacco smoke filter or filter element according to claim 1, which further comprises an additive.

33. The tobacco smoke filter or filter element according to claim 32, wherein the additive is infused in the paper or other non-cellulose acetate containing filtering material or contained within a capsule or the cavity.

34. A smoking article comprising a tobacco smoke filter according to claim 1, or a tobacco smoke filter including a filter element according to claim 1, joined to a wrapped tobacco rod with one end of the filter facing towards the tobacco rod.

35. A multiple rod comprising a plurality of tobacco smoke filters or filter elements according to claim 1, integrally joined end-to-end.

Description

[0042] FIG. 1 shows a schematic view of the tobacco smoke filter or filter element according to an embodiment of the invention;

[0043] FIG. 2 shows a cross-section, not to scale, view of FIG. 1 when cut along the filter's longitudinal axis;

[0044] FIG. 3 shows a schematic view of a tobacco smoke filter or filter element according an embodiment of the invention;

[0045] FIG. 4 shows a cross-section, not to scale, view of FIG. 3 when cut along the filter's longitudinal axis.

[0046] FIGS. 1 and 2 show a tobacco smoke filter or filter element 100 according to an embodiment of the invention. The tobacco smoke filter 100 comprises a longitudinally extending cylindrical core 106 of length 27 mm and circumference 24 mm which includes two plugs 101 and 102 of Myria® paper filtering material (300 36 g/m.sup.2 SWM) each of length 9 mm, distanced longitudinally from each other. Engaged around each plug 101 and 102 are wrappers 103 and 104 formed of sheets of non-porous plug wrap of 27 g/m.sup.2 weight. A further wrapper 105 of stiff plug wrap of 78 g/m.sup.2 weight is engaged around the plugs 101 and 102 to define a cavity 107 of length 9 mm between the plugs 101 and 102. Both ends of the further wrapper 105 are flush with the end of plugs 101 and 102. The further wrapper 105 has an overlapping longitudinal edge with adhesive applied thereon which provides a lapped and stuck seam (not shown) holding the further wrapper 105 around the plugs 101 and 102 and a further adhesive in anchor lines (not shown) in register with the plugs 101 and 102 to hold the plugs in place.

[0047] FIGS. 3 and 4 show a tobacco smoke filter or filter element of length 25 mm and circumference 24.5 mm according to a further embodiment of the invention. The tobacco smoke filter 200 comprises a longitudinally extending cylindrical core 201 of length 18 mm which includes a plug 202 of Puracel® paper filtering material (300 mm Puracel® FM26 g/m.sup.2 SWM) wrapped in a non-porous plug wrap 203 (not shown in FIG. 3) of 27 g/m.sup.2 weight. Engaged around the longitudinally extending cylindrical core 201 is a further wrapper of stiff plug wrap 205 of 78 g/m.sup.2 weight that extends beyond one end of the longitudinally extending cylindrical core 201 around which it is engaged by 7 mm, to define a tubular recess 204 of length 7 mm at that end of the filter. The other end of the further wrapper 205 is flush with the end of plug 202.

[0048] It will be appreciated that the tobacco smoke filters 100 and 200 may be made by methods known in the art and may be prepared as a multiple rod comprising a plurality (e.g. 2, 4, 6 etc.) of tobacco smoke filters or filter rods integrally joined end-to-end. The tobacco smoke filters 100 and 200 may be joined, at either end, to a wrapped tobacco rod to form a cigarette, by methods well known in the art.

EXAMPLE

[0049] Tobacco smoke filters A, B and C of the invention were made according to methods known in the art.

[0050] Tobacco smoke filter A comprises a longitudinally extending cylindrical core of length 25 mm and circumference 24.5 mm, which includes two plugs of Myria® paper filtering material (280 mm 36 g/m.sup.2 SWM) each of length 8 mm, distanced longitudinally from each other. Engaged around each plug of Myria® paper filtering material is a wrapper of non-porous plug wrap of 27 g/m.sup.2 weight. A further wrapper of stiff plug wrap of 78 g/m.sup.2 weight is engaged around the plugs of Myria® paper filtering material such that the further wrapper defines a cavity of length 9 mm between the plugs of wrapped Myria® paper filtering material. The further wrapper of stiff plug wrap contains an infused flavour modifier (as described in WO2010/136751) to remove the deleterious “paper taste”.

[0051] Tobacco smoke filter B comprises a longitudinally extending cylindrical core of length 25 mm and circumference 24.5 mm, which includes a plug of Puracel® paper filtering material (300 mm Puracel® FM26 g/m.sup.2 SWM) of length 8 mm and a plug of Myria® paper filtering material (280 mm 36 g/m.sup.2 SWM) of length 8 mm, distanced longitudinally from each other. Engaged around the plug of Puracel® paper filtering material and the plug of Myria® paper filtering material are wrappers of non-porous plug wrap of 27 g/m.sup.2 weight. A further wrapper of stiff plug wrap of 78 g/m.sup.2 weight is engaged around the plugs of wrapped Puracel® and wrapped Myria® paper filtering material such that the further wrapper defines a cavity of length 9 mm between the plugs of wrapped Puracel® and wrapped Myria® paper filtering material.

[0052] Tobacco smoke filter C comprises a longitudinally extending cylindrical core of length 25 mm and circumference 24.5 mm, which includes a plug of Puracel® paper filtering material (300 mm Puracel® FM26 g/m.sup.2 SWM) of length 18 mm, wrapped in non-porous 27 g/m.sup.2 plug wrap.

[0053] A further wrapper of stiff plug wrap of 78 g/m.sup.2 is engaged around the longitudinally extending cylindrical core and extends beyond one end of the longitudinally extending cylindrical core to define a tubular recess of length 7 mm at the end of the filter. The other end of the further wrapper of stiff plug wrap of 78 g/m.sup.2 weight is flush with the other end of the longitudinally extending cylindrical core.

[0054] The filtration efficiency (at a pressure drop of 100 mmWG) and firmness (of the paper or other non-cellulose acetate containing filtering material segment) of tobacco smoke filter A, tobacco smoke filter B and tobacco smoke filter C were estimated and compared to the filtration efficiency (at a pressure drop of 100 mmWG) and firmness of tobacco smoke filter D, a conventional 27 mm mono acetate tobacco smoke filter wrapped in a non-porous plug wrap of weight 27 g/m.sup.2, length 25 mm and circumference 24.5 mm. The results are illustrated in Table 1.

[0055] To measure the filtration efficiency and firmness of tobacco smoke filter D, the filter was joined to a wrapped tobacco rod to form a cigarette by methods known in the art. The average firmness and tar retention were measured by methods well known in the art (for filtration efficiency ISO 3308:2012 specifies Routine analytical cigarette-smoking machine-Definitions and standard conditions).

TABLE-US-00001 TABLE 1 Tar Retention Firmness %* %** Filter A 62.0 90 Filter B 56.0 90 Filter C 59.5 90 Filter D 59.0 89 *Estimated for filter A, filter B and filter C **Estimated for filter A, filter B and filter C

[0056] The applicants have surprisingly found that a tobacco smoke filter or filter element which includes a paper or other non-cellulose acetate containing filtering material together with void spaces in the form of cavities and/or recesses, can provide the same (or at least similar) firmness, filtration efficiency and/or tar and nicotine retention (at a given pressure drop) as a conventional cellulose acetate filter of the same dimensions (e.g. the same length and diameter/circumference) and has the advantage of being readily biodegradable. In particular, the use of Puracel® paper filtering material may even reduce the retention of tar and nicotine, compared to a conventional cellulose acetate filter.

[0057] Further, the void spaces in the form of cavities and/or recesses and the use of an infused flavour modifier within the paper filter can achieve a similar tar and nicotine retention compared to a conventional cellulose acetate filter and improves the “paper taste” associated with typical paper filters. Thus the applicants have found that the inclusion of cavities and/or recesses within a filter comprising paper or other non-cellulose acetate containing filtering material provide a smoking experience that is comparable to that from a conventional cellulose acetate filtered cigarette.