SMOKING ARTICLE HAVING TRANSPARENT WRAPPER

Abstract

A mouthpiece for a smoking article comprises at least one mouthpiece element; a substantially transparent wrapper wrapped around the at least one mouthpiece element such that first and second opposed edges of the substantially transparent wrapper (18) overlap with each other along a longitudinal overlapping region; and an agent disposed between the first and second opposed edges of substantially transparent in at least a portion of the longitudinal overlapping region. The substantially transparent wrapper comprises an acetate ester of cellulose, and the agent comprises an ester of glycerol.

Claims

1. A mouthpiece for a smoking article comprising: at least one mouthpiece element; a substantially transparent wrapper comprising an acetate ester of cellulose, the substantially transparent wrapper being wrapped around the at least one mouthpiece element such that first and second opposed edges of the substantially transparent wrapper overlap with each other along a longitudinal overlapping region; and a substantially transparent seam formed in the substantially transparent wrapper by an agent comprising an ester of glycerol disposed between the first and second opposed edges of the substantially transparent wrapper in at least a portion of the longitudinal overlapping region.

2. A mouthpiece according to claim 1, wherein the acetate ester of cellulose is selected from the group of cellulose acetate, cellulose diacetate and cellulose triacetate.

3. A mouthpiece according to claim 1, wherein the substantially transparent wrapper consists essentially of an acetate ester of cellulose.

4. A mouthpiece according to claim 1, wherein the at least one mouthpiece element comprises at least one plug of filtration material.

5. A mouth piece according to claim 4, wherein the at least one plug of filtration material comprises at least two segments of filtration material spaced apart to form a cavity therebetween.

6. A mouthpiece according to claim 1, wherein the transparency level of the overlapping region of the substantially transparent wrapper is within 10 percent of the transparency level of the remainder of the substantially transparent wrapper.

7. A mouthpiece according to claim 1, wherein the substantially transparent wrapper has a thickness of between 10 microns and 100 microns.

8. A mouthpiece according to claim 1, wherein the ester of glycerol is triacetin.

9. A mouthpiece according to claim 1, further comprising a paper wrapper circumscribing at least a portion of the substantially transparent wrapper, and a window provided in the paper wrapper so that a portion of the underlying substantially transparent wrapper can be viewed through the window.

10. A smoking article comprising: an aerosol generating substrate; and a mouthpiece according to claim 1 in axial alignment with the aerosol generating substrate.

11. A smoking article according to claim 10, wherein the paper wrapper secures the mouthpiece to the aerosol generating substrate.

12. A method of forming a mouthpiece for a smoking article, the method comprising: providing at least one mouthpiece element; providing a substantially transparent wrapper comprising an acetate ester of cellulose, the substantially transparent wrapper having first and second opposed edges; disposing an agent adjacent to the first opposed edge of the substantially transparent wrapper, the agent comprising an ester of glycerol; wrapping the substantially transparent around the at least one mouthpiece element such that the first and second opposed edges of the substantially transparent wrapper overlap with each other along a longitudinal overlapping region; wherein the ester of glycerol of the agent reacts with the acetate ester of cellulose to secure the opposed edges to one another.

13. A method according to claim 12, further comprising the step of: method further comprises the step of heating the substantially transparent wrapper, heating the agent comprising an ester of glycerol, or heating both the substantially transparent wrapper and the agent comprising an ester of glycerol to a temperature of between 70 degrees Celsius and 80 degrees Celsius.

14. A method according to claim 12, further comprising the step of: applying a compressive force to the longitudinal overlapping region.

15. A method according to claim 12, wherein the acetate ester of cellulose is selected from the group of cellulose acetate, cellulose diacetate and cellulose triacetate.

Description

[0044] The invention will now be further described, by way of example only, with reference to the accompanying drawings in which:

[0045] FIG. 1 shows a smoking article in accordance with the present invention;

[0046] FIG. 2 shows the smoking article of FIG. 1 with the mouthpiece unwrapped; and

[0047] FIG. 3 shows a cross sectional view of the overlapping region of the substantially transparent wrapper of FIG. 1.

[0048] The filter cigarette 10 shown in FIGS. 1 and 2 comprises a wrapped rod 12 of tobacco cut filler which is attached at one end to an axially aligned filter 14 comprising a single filter segment 16. The single filter segment 16 is formed of cellulose acetate tow which has been wrapped with a substantially transparent wrapper in the form of substantially transparent plug wrap 18. The filter segment 16 incorporates particles of a cellulosic material (not shown) impregnated with a liquid flavourant, which are dispersed within the cellulose acetate tow. The wrapped tobacco rod 12 and the filter 14 are joined by an outer wrapper 20 formed of standard tipping paper, which circumscribes the entire length of the filter 14 and an adjacent portion of the tobacco rod 12. The outer wrapper 20 is secured to the substantially transparent plug wrap 18 at adhesive bond points (not shown) spaced around the circumference of the filter 14.

[0049] The outer wrapper 20 comprises a circular cut-out portion 22 having a diameter of approximately 5 mm which is positioned approximately 5 mm from the rod end of the outer wrapper 20. The underlying substantially transparent plug wrap 18 is exposed through the cut-out portion 22 in the outer wrapper 20 and an area of the filter including the cellulosic granules is therefore visible through the cut-out portion 22.

[0050] The substantially transparent plug wrap 18 is formed from a cellulose diacetate film. A first portion 19 of the substantially transparent plug wrap 18 is provided with an agent comprising triacetin. The first portion 19 is adjacent to a first edge of the plug wrap 18, which is configured to be wrapped around the filter segment 16, such that the first edge overlaps with a second opposed edge of the substantially transparent wrapper along a longitudinal overlapping region. When overlapped the agent reacts with the cellulose diacetate in the overlapping portions of the plug wrap 18 to secure them together.

[0051] As can be seen from FIG. 3, the resultant overlapping portion 30 has a thickness 37 of about two times the thickness 35 of the remainder of the wrapper 34. The agent 32 therefore results in an effectively seamless transition of the film from one overlapping piece to the other. In the FIG. 3 arrangement, the agent 32 has not been provided across the entire width of the overlapping region 30. Consequently, the tips 38, 39 of the two overlapping edges are not secured to their corresponding portions of overlapping wrapper.