Biodegradable Segment of a Smoking Article

Abstract

A segment of a smoking article is shown, comprising a fiber-based web material and a wrapping material, which wraps the fiber-based web material, wherein the fiber-based web material comprises at least 40% pulp fibers and less than 10% non-natural polymers, respectively with respect to the mass of the web material, has a basis weight of at least 10 g/m.sup.2 and at most 70 g/m.sup.2, and has a thickness of at least 25 m and at most 400 μm, wherein said web material in the segment has an area of at least 20 cm.sup.2 and at most 90 cm.sup.2 per cm.sup.3 volume of the segment, wherein the segment without the wrapping material has a density of at least 50 kg/m.sup.3 and at most 300 kg/m.sup.3, and wherein a parameter Z, which is defined by Z=ρ.sub.Web+5.Math.ρ.sub.seg+12.Math.A.sub.Web, satisfies the inequality 1300≤Z≤2800, wherein ρ.sub.Web is the density of the web material in kg/m.sup.3, ρ.sub.Seg is the density of the segment without wrapping material in kg/m.sup.3, and A.sub.Web is the area of the web material per volume of the segment in cm.sup.2/cm.sup.3.

Claims

1. Smoking article, comprising an aerosol-forming material which during smoking is heated, but not burnt, and segment, said segment comprising a fiber-based web material and a wrapping material, which wraps the fiber-based web material, wherein the fiber-based web material comprises at least 40% pulp fibers and less than 10% non-natural polymers, respectively with respect to the mass of the web material, has a basis weight of at least 10 g/m.sup.2 and at most 70 g/m.sup.2, and has a thickness of at least 25 μm and at most 400 μm, wherein said web material in the segment has an area of at least 20 cm.sup.2 and at most 90 cm.sup.2 per cm.sup.3 volume of the segment, wherein the segment without the wrapping material has a density of at least 50 kg/m.sup.3 and at most 300 kg/m.sup.3, and wherein a parameter Z, which is defined by Z=ρ.sub.Web+5.Math.ρ.sub.seg+12.Math.A.sub.Web, satisfies the inequality 1300≤Z≤2800, wherein ρ.sub.Web is the density of the web material in kg/m.sup.3, ρ.sub.Seg is the density of the segment without wrapping material in kg/m.sup.3, and A.sub.web is the area of the web material per volume of the segment in cm.sup.2/cm.sup.3, wherein the wrapping material is formed by paper with a basis weight of at least 20 g/m.sup.2 and at most 150 g/m.sup.2, and wherein the wrapping material has a bending stiffness of at least 0.05 Nmm and at most 0.00 Nmm.

2. Smoking article according to claim 1, wherein the content of pulp fibers in the web material is at least 60% with respect to the mass of the web material.

3. Smoking article according to claim 1, wherein the pulp fibers are formed by wood pulp fibers which are sourced from deciduous trees or coniferous trees, from hemp, flax, sisal, jute, abaca or esparto grass, or mixtures thereof.

4. Smoking article according to claim 1, wherein the web material contains less than 5% of its mass of non-natural polymers.

5. Smoking article according to claim 1, wherein the web material contains fibers from regenerated cellulose, wherein their content is less than 6% of the mass of the web material.

6. Smoking article according to claim 1, wherein the web material contains filler materials, wherein the filler materials are formed by calcium carbonate, magnesium oxide, magnesium hydroxide, aluminum hydroxide, titanium dioxide, silicates or mixtures thereof.

7. Smoking article according to claim 1, wherein the content of filler materials with respect to the mass of the web material is at least 5% and at most 35%.

8. Smoking article according to claim 1, wherein the web material is coated with polyvinyl alcohol or a polysaccharide.

9. Smoking article according to claim 1, wherein the web material is impregnated with glycerol or propylene glycol.

10. Smoking article according to claim 1, wherein the web material contains flavors, wherein the flavors are contained in the web material in a chemically bound form or in a physically bound form.

11. Smoking article according to claim 1, wherein the basis weight of the web material is between 20 g/m.sup.2 and 60 g/m.sup.2.

12. Smoking article according to claim 1, wherein the thickness of the web material is between 35 μm and 150 μm.

13. Smoking article according to claim 1, wherein the density of the web material is between 200 kg/m.sup.2 and 700 kg/m.sup.3.

14. Smoking article according to claim 1, which contains between 35 cm.sup.2/cm.sup.3 and 70 cm.sup.2/cm.sup.3 of web material per cm.sup.3 volume of the segment.

15. Smoking article according to claim 1, with a density, without the wrapping material, which between 70 kg/m.sup.3 and 200 kg/m.sup.3.

16. Smoking article according to claim 1, wherein the parameter Z is at least 1350 and at most 2600.

17. Smoking article according to claim 1, wherein the wrapping material is formed by paper with a basis weight of at least 50 g/m.sup.2 and at most 120 g/m.sup.2.

18. Smoking article according to claim 1, wherein the wrapping material has a bending stiffness of at least 0.10 mm and at most 0.80 Nmm.

19. Smoking article according to claim 1, wherein the segment is cylindrical and has a diameter of at least 5 mm and at most 9 mm.

20. Smoking article according to claim 1, wherein the segment is at least 4 mm and at most 40 mm long.

21. (canceled)

22. (canceled)

23. Smoking article according to claim 1, wherein the segment is arranged between the aerosol-forming material and a filter segment.

24. Smoking article according to claim 1, wherein the content of pulp fibers in the web material is at least 90% with respect to the mass of the web material.

25. Smoking article according to claim 8, wherein the polysaccharide is selected from the group consisting of starch, carboxymethylcellulose, guar, dextrin, pectin or mixtures thereof.

26. Smoking article according to claim 10, wherein the flavors are selected from the group consisting of menthol, ethyl vanillin glucoside, vanillin and ethyl vanillin.

27. Smoking article according to claim 1, wherein the parameter Z is at least 1400 and at most 2400.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0053] FIG. 1 shows a table (Table 1), in which the compositions of 25 web materials are summarized.

[0054] FIG. 2 shows a table (Table 2), in which characteristic properties of the web materials (width, basis weight, thickness, density) of the 25 web materials of Table 1 are summarized.

[0055] FIG. 3 shows a table (Table 3), in which characteristic properties (mass, density, area, parameter Z) of 25 segments, which were manufactured from the web materials of Tables 1 and 2, are summarized.

[0056] FIG. 4 shows a table (Table 4), in which functional properties of the segments of Table 3 (draw resistance, filtration efficiency for nicotine, water and glycerol) are summarized.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0057] The invention will now be described more precisely by way of a few embodiments according to the invention and compared with examples not according to the invention.

[0058] Different fiber-based web materials were manufactured according to processes known in the art and reels with a width of 175 mm to 315 mm were cut. The reels of the web materials were crimped and of each a continuous rod was manufactured and wrapped with a wrapping material with a basis weight of 78 g/m.sup.2. The rod with the wrapping material had a diameter of 7.85 mm, wherein the wrapping material had a width of 27 mm and thus overlapped by about 2.3 mm for gluing to itself.

[0059] The composition of the web materials is given in Table 1. All of the web materials were manufactured from wood pulp; for the two web materials No. 22 and 23 Lyocell® fibers were also used, wherein the indicated percentage of 40% is with respect to the mass of Lyocell® fibers in the total fiber mass in the web material. The web materials 4-6, 12 and 13 also contained 29.5% of their mass of precipitated calcium carbonate (CaCO.sub.3).

[0060] Web materials 16-21, 24 and 25 were coated with an oxidized starch and the web materials 14, 15, 18 and 19 were impregnated with glycerol. The web materials 20 and 21 were impregnated with propylene glycol.

[0061] The basis weight of the web materials was determined in accordance with ISO 536:2012 and the thickness and the density were determined in accordance with ISO 534:2011. The results are given in Table 2, wherein the numbers of the web materials correspond to those of Table 1.

[0062] The rods manufactured from the web materials were cut into rods each with a length of 108 mm and their mass was determined by weighing.

[0063] The data for the rods manufactured from the web materials 1-25 are given in Table 3, wherein again, the numbers of the web materials correspond to those of Table 1. The mass in Table 3 in this regard is the mass of a 108 mm long rod with a wrapping material with a basis weight of 78 g/m.sup.2. The density was calculated as follows from the mass of the rod and the known geometry.

[0064] The mass of the wrapping material, which was 27 mm wide and 108 mm long, was

78 g/m.sup.2×0.027 m×0.108 m=0.227 g.

[0065] The volume of the rod was calculated from the known geometry, thus

π/4×(7.85 mm).sup.2×108 mm=5227 mm.sup.3.

[0066] In this regard, the thickness of the wrapping material was ignored. The mass of the wrapping material was subtracted from the mass of the rod with wrapping material and the result was divided by the volume. Thus, for example, the density of the rod manufactured from web material 1 was

(0.71g−0.227 g)/5227 mm.sup.3=92.4 kg/m.sup.3.

[0067] The parameter Z is also shown in Table 3, which is calculated from

Z=ρ.sub.Web+5.Math.ρ.sub.seg+12.Math.A.sub.Web,

[0068] wherein

[0069] ρ.sub.Web is the density of the web material in kg/m.sup.3

[0070] ρ.sub.Seg is the density of the segment without wrapping material in kg/m.sup.3, and

[0071] A.sub.Web is the area of the web material per volume of the segment in cm.sup.2/cm.sup.3.

[0072] The parameter Z is independent of the geometry, in particular the diameter and the length of the rod or the segment, and characterizes only the inner structure of the segment.

[0073] The draw resistance of the 108 mm long rods was measured in accordance with ISO 6565. Segments with a length of 18 mm were cut from the rods, and smoking articles manufactured therefrom.

[0074] The smoking article was a so-called heated tobacco product, in which the tobacco contained in the smoking article is only heated. The smoking article consisted of a segment with the tobacco followed in the flow direction by a transfer segment, in which the aerosol can condense, and further followed by the segment according to the invention, which here primarily serves to cool the aerosol, and finally by a filter segment.

[0075] The smoking article was heated in a commercially available heating device and smoked in accordance with the method given in ISO 3308. The filtration efficiency for nicotine, water and glycerol was measured for the segments manufactured from the web materials 8-25. In this regard, the filtration efficiency is the difference between the amount of substance flowing into the segment and the amount of substance flowing out of the segment, with respect to the amount of substance flowing into the segment. The filtration efficiency is expressed as a percentage and was determined by this method for nicotine, water and glycerol for an 18 mm long segment.

[0076] In Table 4, the draw resistance of a 108 mm long rod and the filtration efficiency of an 18 mm long segment for nicotine, water and glycerol are shown. Here again, the numbers of the web materials correspond to those of Table 1.

[0077] The segments manufactured from the web materials 1-25 are segments according to the invention, which have a parameter Z of about 1300 to about 2250. The draw resistance of the 108 mm long rod is between 17.9 mmWG and 63.9 mmWG and enables the design of segments, which either transfer the aerosol and only have a low draw resistance or which filter the aerosol and additionally allow the draw resistance to be increased. In particular, a comparison of the web materials 2 and 11, which are identical with respect to their composition, show the influence of the density of the segment on the draw resistance. A segment from web material 2 with a density of the segment of 73.3 kg/m.sup.3 provides a draw resistance (108 mm) of 23.8 mmWG, while a segment manufactured from web material 11 with a density of 170.5 kg/m.sup.3 has a draw resistance (108 mm) of 54.5 mmWG. This shows the importance of the density of the segment, for which reason it is an essential component of the parameter Z. The draw resistance, however, is not solely determined by the density of the segment.

[0078] The web materials 6 and 7 have similar basis weights, wherein web material 6, however, contains 29.5% calcium carbonate and thus has a substantially higher density. The segments manufactured therefrom have similar densities and also the area of the web material per volume of the segment is similar. Nevertheless, they differ substantially in draw resistance, which is 63.9 mmWG for the rod (108 mm) manufactured from web material 6 and 30.5 mmWG for the rod (108 mm) manufactured from web material 7. This shows that the density of the web material itself has an independent effect on the properties of the segment manufactured therefrom and thus also constitutes an essential component of the parameter Z.

[0079] The area of the web material per volume of the segment depends on the density of the web material and the density of the segment without wrapping material, and thus is also an essential property of the draw resistance and therefore is also a component of the parameter Z.

[0080] The segments of the web materials 16-21 coated with starch all exhibit a lower filtration efficiency for water than the segments from the comparable web materials 8, 9 and 11, while they hardly differ in the filtration efficiencies for nicotine and glycerol. This therefore shows that a coating with oxidized starch can be used to adjust the filtration efficiency for water.

[0081] Impregnation of the web materials 18-21 with glycerol or propylene glycol results in a substantially higher filtration efficiency for nicotine and glycerol in the segments manufactured therefrom compared with the segments from the web materials 16 and 17, which do not have such an impregnation. Thus, the filtration efficiency for nicotine and glycerol can be adjusted by the impregnation.

[0082] In summary, all segments manufactured from the web materials 1-25 are useful as segments in a smoking article and can serve for cooling the aerosol as well as for filtration of the aerosol. The biodegradability of all segments manufactured from the web materials 1-25 resulted directly from the components used and was not tested further. It was shown that with the segments according to the invention, favorable properties for use in smoking articles can be obtained and additionally, excellent biodegradability can be achieved.

[0083] The following two examples that are not according to the invention show that the parameter Z is essential to the differentiation between segments according to the invention and segments not according to the invention.

[0084] A segment with a density without wrapping material of 90.4 kg/m.sup.3 and an area of the web material per volume of the segment of 36.9 cm.sup.2/cm.sup.3 was manufactured from web material 7.

[0085] The parameter Z for this is segment was

350.0+5.Math.90.4+12.Math.36.9=1244.8

[0086] and thus lies outside the range according to the invention of 1300 to 2800.

[0087] The 108 mm long rod from this web material had a draw resistance of just 12.3 mmWG, which is too low for application in smoking articles. In addition, the hardness of the segment despite the wrapping material with 78 g/m.sup.2 is not sufficient for further processing into a smoking article. It should be noted that this segment satisfied all of the requirements according to the invention, with the exception of those related to parameter Z.

[0088] A segment with a density without the wrapping material of 233.9 kg/m.sup.2 and an area of the web material per volume of the segment of 89.9 cm.sup.2/cm.sup.3 was manufactured from web material 12. The parameter Z for this segment was

604.7+5 233.9+12 0.89.9=2853.6

[0089] and thus lies outside the range according to the invention of 1300 to 2800.

[0090] The filtration efficiency of this segment for water was more than 65% despite the high content of calcium carbonate in web material 12, and therefore produced too dry an aerosol and thus resulted in a taste which was not acceptable to the consumer. It should be noted that again, this segment satisfied all of the requirements according to the invention, with the exception of those related to parameter Z.

[0091] The two comparative examples not according to the invention thus show that the parameter Z is essential for obtaining a segment with satisfactory properties.