Filter Element For A Smoking Article

Abstract

A filter element for a smoking article has one end for connection to a rod element of smokeable material and an opposite end for insertion into a mouth of a user. The filter element includes: one or more filter segments provided on or arranged along a longitudinal axis of the filter element, at least one of the filter segments including a filter material; a wrapper which surrounds and wraps the one or more filter segments; and a liquid-filled breakable capsule arranged within one of the one or more filter segments, the capsule having a rupture point at which the capsule is designed to break or rupture upon application of external force to release liquid contained therein. The capsule is arranged in the one filter segment with the rupture point located at a first distance along the longitudinal axis from the one end of the filter element.

Claims

1. A smoking article, comprising a rod element of smokeable material connected to a filter element by a tipping wrapper, the filter element having a first end for connection to the rod element and an opposite, second end for insertion into a mouth of a user, the filter element comprising: a liquid-filled directional capsule arranged between the first and second ends of the filter element, the directional capsule having a rupture region at which the directional capsule is designed to break upon application of external force to release liquid contained therein, wherein the smoking article comprises a ventilation zone arranged between the first end of the filter element and the rupture region of the directional capsule.

2. The smoking article according to claim 1, wherein the ventilation zone comprises a plurality of perforations provided through the tipping wrapper and/or extending into a portion of the filter element.

3. The smoking article according to claim 1, wherein a distance between the rupture region of the directional capsule and the ventilation zone is at least 1 mm.

4. The smoking article according to claim 1, wherein a distance between the first end of the filter element and the ventilation zone is at least 1 mm.

5. The smoking article according to claim 1, wherein the directional capsule contains a liquid volume of at least 0.05 ml.

6. The smoking article according to claim 1, wherein the filter element further comprises a filter wrapper at least partly extending between the first and second ends of the filter element.

7. The smoking article according to claim 6, wherein the basis weight of the filter wrapper (8) is of at least 40 g/m.sup.2.

8. The smoking article according to claim 6, wherein the Cobb water absorption of the filter wrapper is of no more than 35 g/m.sup.2.

9. The smoking article according to claim 1, wherein the Cobb water absorption of the tipping wrapper is of no more than 25 g/m.sup.2.

10. A filter element for a smoking article, the filter element having a first end for connection to a rod element of smokeable material and an opposite, second end for insertion into a mouth of a user, the filter element comprising: a liquid-filled directional capsule arranged between the first and second ends, the directional capsule having a rupture region at which the directional capsule is designed to break upon application of external force to release liquid contained therein, wherein the filter element comprises a ventilation zone arranged between the first end and the rupture region of the directional capsule.

11. The filter element according to claim 10, wherein a distance between the rupture region of the directional capsule and the ventilation zone is at least 1 mm.

12. The filter element according to claim 10, wherein a distance between the first end of the filter element and the ventilation zone is at least 1 mm.

13. The filter element according to claim 10, wherein the directional capsule contains a liquid volume of at least 0.05 ml.

14. The filter element according to claim 10, further comprising a filter wrapper at least partly extending between the first and second ends of the filter element.

15. The filter element according to claim 14, wherein the Cobb water absorption of the filter wrapper is less than about 30 g/m.sup.2.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0040] For a more complete understanding of the invention and the advantages thereof, exemplary embodiments of the invention are explained in more detail in the following description with reference to the accompanying drawing figures, in which like reference characters designate like parts and in which:

[0041] FIG. 1 is a schematic cross-sectional side view of a filter element for a smoking article according to a preferred embodiment;

[0042] FIG. 2 is a schematic cross-sectional side view of a smoking article according to a preferred embodiment which includes the filter element of FIG. 1; and

[0043] FIG. 3 is a flow diagram illustrating steps in a method of manufacturing a filter element according to a preferred embodiment.

DETAILED DESCRIPTION

[0044] The accompanying drawings are included to provide a further understanding of the present invention and are incorporated in and constitute a part of this specification. The drawings illustrate particular embodiments of the invention and together with the description serve to explain the principles of the invention. Other embodiments of the invention and many of the attendant advantages of the invention will be readily appreciated as they become better understood with reference to the following detailed description.

[0045] It will be appreciated that common and well understood elements that may be useful or necessary in a commercially feasible embodiment are not necessarily depicted in order to facilitate a more abstracted view of the embodiments. The elements of the drawings are not necessarily illustrated to scale relative to each other. It will further be appreciated that certain actions and/or steps in an embodiment of a method may be described or depicted in a particular order of occurrences while those skilled in the art will understand that such specificity with respect to sequence is not actually required. It will also be understood that the terms and expressions used in the present specification have the ordinary meaning as is accorded to such terms and expressions with respect to their corresponding respective areas of inquiry and study, except where specific meanings have otherwise been set forth herein.

[0046] With reference to FIG. 1 and FIG. 2 of the drawings, a filter element 1 for a smoking article 10, such as a cigarette, according to a preferred embodiment is illustrated schematically. The filter element 1 has a generally elongate cylindrical form and has a first end 2 for connection to a rod element 11 of smokeable material (i.e. a tobacco rod), and an opposite, second end 3 for insertion into a mouth of a user. The filter element 1 of this embodiment comprises three filter segments 4, 5, 6 arranged in series along a longitudinal axis X of the filter element. Two of these three filter segments 4, 5, 6namely, the first and the third filter segments 4, 6are comprised substantially entirely of a fibrous filtration material such as cellulose acetate tow. The second or central filter segment 5 is a cavity that comprises a liquid-filled directional capsule 7 located within it. Alternatively, the liquid-filled directional capsule 7 could be surrounded by filtration material such as cellulose acetate tow. The liquid-filled directional capsule 7 is configured with a weakened region that forms a rupture point P at which the directional capsule is designed to break or rupture upon application of a lateral external force F to release a liquid L contained therein. The directional capsule 7 is arranged with the rupture point P located generally on the longitudinal axis X in the filter element 1 such that, upon breaking or rupture of the directional capsule 7, the liquid L is released in the axial direction X into an adjacent region of cellulose acetate tow filtration material in the filter segment 6. In this way, when a user smoking the smoking article 10 in FIG. 2 draws on the mouth end 3 of the filter element 1, the released liquid L acts to impart a desired flavour to the mainstream smoke passing through the filter element 1.

[0047] The filter element 1 further includes a wrapper or plug wrap 8 of a sheet material, such as paper or a synthetic film, which surrounds and envelops or encompasses the filter segments 4, 5, 6 thereby unifying or uniting them within the filter element. The first and third filter segments 4, 6 may comprise a filter wrapper (not shown) so that, when combined to form the filter element 1 by the combiner filter wrapper 8, the fibrous filtration material in the first and third filter segments 4, 6 is surrounded by two filter wrappers, the filter segment wrapper and the combiner filter wrapper 8.

[0048] As a result of this multi-segment or multi-component filter configuration, liquid L released from the directional capsule 7 is directed towards an interface of the adjacent filter segment, the third filter segment 6, which increases the likelihood of liquid leakage, especially when the directional capsule 7 is located in a cavity filter segment 5, as some liquid may bounce off the interface of the adjacent filter segment 6 and go into the space between the filter wrapper 8 and the directional capsule 7. By providing a ventilation zone between the rupture point P of the directional capsule 7 and the first end 2 of the filter element 1, the filter element 1 may be ventilated through the filter element 1 while mitigating liquid leakage.

[0049] The filter wrapper or plug wrap 8 includes a series of holes or perforations 9 and these operate, in use, to admit air laterally into the filter element 1 to reduce or dilute mainstream smoke being drawn through the filter element 1 from the tobacco rod element 11. In other words, the series of holes or perforations 9 provide ventilation. The directional capsule 7 is arranged in the central filter segment 5 with its rupture point P located at a first distance D1 along the longitudinal axis X from the tobacco rod end 2 of the filter element 1. The holes or perforations 9 in the wrapper 8 are provided at a second distance D2 along the longitudinal axis X from the tobacco rod end 2 of the filter element 1. The first distance D1 in regard to the rupture point P is selected to be greater than the second distance D2 with regard to the holes or perforations 9 in the wrapper 8, preferably by an amount in the range of about 3 mm to about 5 mm, e.g. about 4 mm. The filter element 1 itself typically has a length in the range of about 15 mm to about 30 mm. In the embodiment shown in FIG. 1, the holes or perforations 9 may partly extend into the fibrous filtration material of the third filter segment 6, and they may do so extending through the filter segment wrapper of the third filter segment 6.

[0050] As can be seen in FIG. 2, the smoking article 10 (e.g. cigarette) comprises the filter element 1 aligned in end-to-end relationship with the tobacco rod 11. The tobacco rod end 2 of the filter element 1 is attached or joined to the adjacent end of the tobacco rod 11 using a circumscribing wrapping material known as a tipping sheet or tipping wrapper 12 which is wrapped around the filter element 1 and a part of the rod element of smokeable material. The part of the tobacco rod 11 encompassed or circumscribed by the strip or band of the tipping sheet 12 has a length which is usually in the range of about 5 mm to about 10 mm (i.e. in the longitudinal or axial direction). The tipping sheet 12 comprises a plurality of perforations 13 located at the second distance D2 from the first end 2 of the filter element 1. These holes or perforations 13 also act to admit air laterally into the filter element 1 to mix with and dilute the mainstream smoke. In this way, the holes or perforations 13 in the tipping sheet 12 are substantially aligned with the holes or perforations 9 in the filter wrapper 8.

[0051] Referring now to FIG. 3 of the drawings, a flow diagram is shown that illustrates schematically various steps in a method of manufacturing a filter element 1 for use in a smoking article 10, such as a cigarette or the like, according to a preferred embodiment of the invention as described above with reference to FIGS. 1 and 2. In this regard, the first box i of FIG. 3 represents the step of providing or arranging one or more filter segments 4, 5, 6 on or along a longitudinal axis X of the filter element, at least one of said one or more filter segments 4, 5, 6 including a filter material. The second box ii represents a step of arranging a liquid-filled breakable capsule 7 within one of the said one or more filter segments 4, 5, 6, the capsule 7 having a rupture point P at which the capsule 7 is designed to break or rupture upon application of external force F to release liquid L contained therein. In this regard, the rupture point P is located at a distance D1 along the longitudinal axis X from an end 2 of the filter element 1 to be positioned adjacent a tobacco rod 11. The third box iii then represents the step of surrounding or encompassing the said one or more filter segments 4, 5, 6 with a wrapper 8 of sheet material, known as plug wrap. The final box iv in FIG. 3 represents the step of configuring or arranging the wrapper 8 such that holes or perforations 9 provided therein are at a second distance D2 along the axis X from the end 2 of the filter element 1 to be positioned adjacent a tobacco rod 11, wherein the second distance D2 is less than the first distance D1.

[0052] Although specific embodiments of the invention have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations exist. It should be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration in any way. Rather, the foregoing summary and detailed description will provide those skilled in the art with a convenient road map for implementing at least one exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope as set forth in the appended claims and their legal equivalents. Generally, this application is intended to cover any adaptations or variations of the specific embodiments discussed herein.

[0053] In this document, the terms comprise, comprising, include, including, contain, containing, have, having, and any variations thereof, are intended to be understood in an inclusive (i.e. non-exclusive) sense, such that the process, method, device, apparatus or system described herein is not limited to those features or parts or elements or steps recited but may include other elements, features, parts or steps not expressly listed or inherent to such process, method, article, or apparatus. Furthermore, the terms a and an used herein are intended to be understood as meaning one or more unless explicitly stated otherwise. Moreover, the terms first, second, third, etc. are used merely as labels, and are not intended to impose numerical requirements on or to establish a certain ranking of importance of their objects.

LIST OF REFERENCE SIGNS

[0054] 1 filter element [0055] 2 tobacco rod end [0056] 3 mouth end [0057] 4 filter segment [0058] 5 filter segment [0059] 6 filter segment [0060] 7 capsule [0061] 8 wrapper or plug wrap [0062] 9 hole or perforation [0063] 10 smoking article [0064] 11 rod element of smokeable material or tobacco rod [0065] 12 tipping paper [0066] 13 hole or perforation [0067] P rupture point [0068] F lateral external force [0069] L liquid [0070] D1 first distance [0071] D2 second distance [0072] X longitudinal axis