Aerosol-generating article comprising a perforated hollow tubular substrate element

Abstract

An aerosol-generating article is provided, including: a rod of aerosol-generating substrate; and a downstream section provided downstream of the rod, the rod including: a hollow tubular substrate element formed of homogenised tobacco material and defining a longitudinal cavity providing an unrestricted flow channel through the element, and an outer wrapper circumscribing the element and arranged such that an empty space is defined between at least a part of an external surface of the element and the outer wrapper, the element including a plurality of perforations providing fluid communication between the longitudinal cavity of the element and the empty space between at least a part of the external surface of the element and the outer wrapper, the plurality of perforations of the element being formed through a peripheral wall of the element, and the outer wrapper including a plurality of perforations overlying the element.

1 .- 15 . (canceled) 
     
     
         16 . An aerosol-generating article, comprising:
 a rod of aerosol-generating substrate; and   a downstream section provided downstream of the rod of aerosol-generating substrate,   wherein the rod of aerosol-generating substrate comprises:
 a hollow tubular substrate element formed of homogenised tobacco material and defining a longitudinal cavity providing an unrestricted flow channel through the hollow tubular substrate element, and 
 an outer wrapper circumscribing the hollow tubular substrate element and arranged such that an empty space is defined between at least a part of an external surface of the hollow tubular substrate element and the outer wrapper, 
 wherein the hollow tubular substrate element comprises a plurality of perforations providing fluid communication between the longitudinal cavity of the hollow tubular substrate element and the empty space between at least a part of the external surface of the hollow tubular substrate element and the outer wrapper, 
 wherein the plurality of perforations of the hollow tubular substrate element is formed through a peripheral wall of the hollow tubular substrate element, and 
 wherein the outer wrapper comprises a plurality of perforations overlying the hollow tubular substrate element. 
   
     
     
         17 . The aerosol-generating article according to  claim 16 , wherein the hollow tubular substrate element further comprises at least two rows of perforations extending circumferentially around the hollow tubular substrate element. 
     
     
         18 . The aerosol-generating article according to  claim 16 , wherein each of the plurality of perforations of the hollow tubular substrate element has an opening area of at least about 0.01 millimetre squared. 
     
     
         19 . The aerosol-generating article according to  claim 16 , wherein the hollow tubular substrate element has a wall thickness that is between about 5 percent and about 40 percent of an external diameter of the hollow tubular substrate element. 
     
     
         20 . The aerosol-generating article according to  claim 16 , wherein within the empty space an external surface of the hollow tubular substrate element and the outer wrapper are separated by at least about 0.1 millimetre in a radial direction. 
     
     
         21 . The aerosol-generating article according to  claim 16 , wherein the outer wrapper and the hollow tubular substrate element are unattached. 
     
     
         22 . The aerosol-generating article according to  claim 16 , wherein the plurality of perforations of the outer wrapper overlies the perforations in the hollow tubular substrate element. 
     
     
         23 . The aerosol-generating article according to  claim 16 ,
 wherein the rod of aerosol-generating substrate further comprises an upstream plug element adjacent to an upstream end of the hollow tubular substrate element, and   wherein the outer wrapper circumscribes the hollow tubular substrate element and at least a part of the upstream element.   
     
     
         24 . The aerosol-generating article according to  claim 23 , wherein at least a part of the hollow tubular substrate element has an external diameter that is at least about 0.2 millimetre less than an external diameter of the upstream plug element. 
     
     
         25 . The aerosol-generating article according to  claim 23 , wherein the rod of aerosol-generating substrate further comprises a downstream plug element adjacent to a downstream end of the hollow tubular substrate element and having a same external diameter as the upstream plug element. 
     
     
         26 . The aerosol-generating article according to  claim 16 , wherein the rod of aerosol-generating substrate further comprises one or more protrusions extending across the empty space between an external surface of the hollow tubular substrate element and the outer wrapper. 
     
     
         27 . The aerosol-generating article according to  claim 16 , wherein the outer wrapper has a basis weight of at least about 80 grams per square metre. 
     
     
         28 . The aerosol-generating article according to  claim 16 , wherein the hollow tubular substrate element is formed of two or more overlapping sheets of homogenised tobacco material. 
     
     
         29 . The aerosol-generating article according to  claim 16 , wherein the downstream section comprises at least one hollow tubular element adjacent to a downstream end of the rod of aerosol-generating substrate. 
     
     
         30 . The aerosol-generating article according to  claim 16 , wherein the downstream section comprises at least one mouthpiece filter element.