FILTER ELEMENT AND METHOD FOR MANUFACTURING THEREOF

Abstract

A filter element for an aerosol-generating article is provided, the filter element including a hollow tubular portion with an inner surface; and a flavourant deposited directly onto the inner surface of the hollow tubular portion. A forming device and a method for manufacturing a filter element for an aerosol-generating article are also provided.

Claims

1.-14. (canceled)

15. A filter element for an aerosol-generating article, the filter element comprising: a hollow tubular portion with an inner surface; and a flavourant deposited directly onto the inner surface of the hollow tubular portion.

16. The filter element according to claim 15, wherein the flavourant is menthol.

17. The filter element according to claim 15, wherein the filter element is a hollow acetate tube.

18. The filter element according to claim 15, wherein the hollow tubular portion is provided in the filter element as a central hollow tubular portion and/or wherein the hollow tubular portion of the filter element is provided to form an airflow path for an aerosol.

19. The filter element according to claim 15, wherein the flavourant is deposited onto the inner surface of the hollow tubular portion such that a volume of filter element material through which air can be drawn essentially remains unchanged.

20. The filter element according to claim 15, wherein a filter material of the filter element comprises cellulose acetate fibers.

21. A forming device for manufacturing a filter rod for an aerosol-generating article, comprising: a tubular element, defining a longitudinal axis and having an inlet to introduce filter material and an outlet to output a filter rod; and a rod-shaped element with a nozzle, which is configured to discharge flavourant, wherein the rod-shaped element is at least partly arranged inside the tubular element, and wherein the nozzle is arranged at an outer surface of the rod-shaped element and configured to discharge the flavourant directly onto an inner surface of the filter rod.

22. The forming device according to claim 21, wherein the rod-shaped element comprises a heating element configured to heat the rod-shaped element.

23. The forming device according to claim 22, wherein the rod-shaped element is hollow such that the rod-shaped element is configured to be heated by circulating steam within the rod-shaped element.

24. The forming device according to claim 21, wherein the rod-shaped element comprises a feed pipe within the rod-shaped element configured to feed the flavourant to the nozzle.

25. The forming device according to claim 21, wherein the tubular element confines an outer shape of the forming device.

26. A method for manufacturing a filter element for an aerosol-generating article, comprising: providing a hollow tubular portion with an inner surface in a filter element; and depositing a flavourant directly onto an inner surface of the hollow tubular portion of the filter element.

27. The method for manufacturing a filter element according to claim 26, further comprising: charging a forming device with an extruded filter material for forming the filter element; providing a rod-shaped element in the forming device, wherein the rod-shaped element comprises a nozzle for discharging the flavourant; positioning the rod-shaped element in the forming device such that a hollow tubular portion is formed in the extruded filter material; and discharging the flavourant from the nozzle of the rod-shaped element such that the flavourant is deposited onto the inner surface of the hollow tubular portion of the extruded filter material.

28. The method for manufacturing a filter element according to claim 27, wherein the rod-shaped element further comprises a heating element for heating the rod-shaped element, and wherein, in a further step, the rod-shaped element is heated to bond the extruded filter material for forming the hollow tubular portion in the extruded filter material.

Description

[0038] The invention will be further described, by way of example only, with reference to the accompanying drawings in which:

[0039] FIG. 1 shows a cross-sectional view of an inventive forming device for manufacturing a filter element for an aerosol-generating article.

[0040] The forming device shown in FIG. 1 comprises a tubular element 10. The tubular element 10 is configured as a funnel-shaped element at the inlet side. The tubular element 10 is shaped so that filter material 12 can be introduced into the tubular element 10.

[0041] The filter material 12 is advanced through the tubular element 10 by conventional means along the direction of the arrow 14, i.e. towards an outlet of the tubular element 10. In that way, a continuous filter rod is created. The forming device may comprise a heating element to heat the filter material 12 while the filter material 12 is advanced through the tubular element 10 such that a bonding agent within the filter material 12 reacts and the filter material 12 is bonded. By bonding the filter material 12, the shape of the finished filter rod is defined.

[0042] The filter rod which is created with the invention is a hollow acetate tube. Consequently, the filter material is cellulose acetate. For creating a hollow tubular portion within the filter rod, a rod-shaped element 16 is arranged inside the tubular element 10. The rod-shaped element 16 has a cylindrical outer shape such that the outer shape of the rod-shaped element 16 defines the inner diameter of the hollow tubular portion of the filter rod. In other words, the diameter of the rod-shaped element 16 defines the diameter of the hollow tubular portion of the finished filter rod.

[0043] The rod-shaped element 16 is provided with a hollow portion 18 such that heated steam can be circulated within the rod-shaped element 16. The rod-shaped element 16 isapart from the entrance area for hot steam indicated by reference numeral 18closed such that the hot steam cannot directly contact the filter material 12. By circulating hot steam within the rod-shaped element 16, the rod-shaped element 16 can be heated to facilitate a bonding of the surrounding filter material 12 while the filter material 12 is advanced through the tubular element 10.

[0044] Additionally, a flavourant 20 is advanced through the rod-shaped element 16 by means of a feed pipe 22 towards a nozzle 24. The flavourant 20 is discharged or sprayed onto the surrounding filter material 12 while the filter material 12 is advanced through the tubular element 10. The flavourant 20 is provided as a liquid flavourant. Consequently, a coating of flavourant 20 is provided on the inner surface of the hollow tubular portion of the filter material 12. In the end, the finished filter rod is provided as a hollow acetate tube with a coating composed of the flavourant. After that, the filter rod can be further processed, for example by cutting the continuous filter rod into smaller filter segments.