Aerosol-generating article with an insulated heat source

Abstract

An aerosol-generating article is provided, including: an aerosol-forming substrate; a combustible heat source; at least one layer of fibre-reinforced aerogel circumscribing at least a portion of a length of the combustible heat source; one or more airflow pathways configured such that air may be drawn along the one or more airflow pathways through the aerosol-generating article and for inhalation by a user; and one or more non-combustible, substantially air-impermeable, barriers disposed between the combustible heat source and the aerosol-forming substrate.

1 .- 15 . (canceled) 
     
     
         16 . An aerosol-generating article, comprising:
 an aerosol-forming substrate;   a combustible heat source;   at least one layer of fibre-reinforced aerogel circumscribing at least a portion of a length of the combustible heat source;   one or more airflow pathways configured such that air may be drawn along the one or more airflow pathways through the aerosol-generating article and for inhalation by a user; and   one or more non-combustible, substantially air-impermeable, barriers disposed between the combustible heat source and the aerosol-forming substrate.   
     
     
         17 . The aerosol-generating article according to  claim 16 , wherein the at least one layer of fibre-reinforced aerogel is isolated from the one or more airflow pathways such that air drawn through the aerosol-generating article along the one or more airflow pathways does not directly contact the at least one layer of fibre-reinforced aerogel. 
     
     
         18 . The aerosol-generating article according to  claim 16 , wherein the combustible heat source, the aerosol-forming substrate, and the at least one layer of fibre-reinforced aerogel are arranged such that a temperature of the aerosol-forming substrate does not exceed 375° C. during combustion of the combustible heat source. 
     
     
         19 . The aerosol-generating article according to  claim 16 , wherein the fibre-reinforced aerogel comprises less than about 80 percent by weight of aerogel. 
     
     
         20 . The aerosol-generating article according to  claim 16 , wherein the fibre-reinforced aerogel comprises at least about 20 percent by weight of fibrous material. 
     
     
         21 . The aerosol-generating article according to  claim 16 , wherein the fibre-reinforced aerogel comprises between about 20 percent by weight and about 70 percent by weight of fibrous material. 
     
     
         22 . The aerosol-generating article according to  claim 16 , wherein the fibre-reinforced aerogel comprises at least one material selected from a ceramic fibrous material and a glass fibrous material. 
     
     
         23 . The aerosol-generating article according to  claim 16 , wherein the at least one layer of fibre-reinforced aerogel has a thickness of between about 0.5 millimetres and about 5 millimetres. 
     
     
         24 . The aerosol-generating article according to  claim 16 ,
 wherein the one or more non-combustible, substantially air-impermeable, barriers between the combustible heat source and the aerosol-forming substrate, and   wherein the aerosol-generating article further comprises a first barrier that abuts one or both of a proximal end of the combustible heat source and a distal end of the aerosol-forming substrate.   
     
     
         25 . The aerosol-generating article according  claim 16 , wherein the one or more airflow pathways comprise one or more air inlets arranged between a proximal end of the combustible heat source and a proximal end of the aerosol-generating article, and are further configured such that air may be drawn into the one or more airflow pathways of the aerosol-generating article though the one or more air inlets, without passing through the combustible heat source. 
     
     
         26 . The aerosol-generating article according to  claim 16 ,
 wherein the one or more airflow pathways comprise one or more airflow channels along the combustible heat source and the one or more non-combustible, substantially air-impermeable, barriers between the combustible heat source and the aerosol-forming substrate, and   wherein the aerosol-generating article further comprises a second barrier disposed between the combustible heat source and the one or more airflow channels of the combustible heat source.   
     
     
         27 . The aerosol-generating article according to  claim 16 , further comprising one or more additional layers circumscribing at least a proximal portion of the combustible heat source and a distal portion of the aerosol-forming substrate, the one or more additional layers comprising a heat-conducting element configured to transfer heat from the combustible heat source to the aerosol-forming substrate, and/or a layer of cigarette paper. 
     
     
         28 . The aerosol-generating article according to  claim 27 , wherein the at least one layer of fibre-reinforced aerogel is a radially outer layer, overlying at least a portion of the one or more additional layers. 
     
     
         29 . A method of forming an aerosol-generating article comprising an aerosol-forming substrate, a combustible heat source, at least one layer of fibre-reinforced aerogel circumscribing at least a portion of a length of the combustible heat source, one or more airflow pathways configured such that air may be drawn along the one or more airflow pathways through the aerosol-generating article and for inhalation by a user, and one or more non-combustible, substantially air-impermeable, barriers disposed between the combustible heat source and the aerosol-forming substrate, the method comprising:
 arranging the combustible heat source so as to heat the aerosol-forming substrate;   providing the one or more airflow pathways along which the air may be drawn through the aerosol-generating article for inhalation by the user;   isolating the combustible heat source from the one or more airflow pathways such that the air drawn through the aerosol-generating article along the one or more airflow pathways does not directly contact the combustible heat source; and   circumscribing at least a portion of a length of the combustible heat source with the at least one layer of fibre-reinforced aerogel.   
     
     
         30 . The method according to  claim 29 , wherein the circumscribing the at least a portion of the length of the combustible heat source with the at least one layer of fibre-reinforced aerogel comprises:
 providing a strip of fibre-reinforced aerogel having opposing ends;   wrapping the strip around the combustible heat source such that the combustible heat source is circumscribed by the at least one layer of fibre-reinforced aerogel;   overlapping the opposing ends of the strip; and   securing together the overlapping ends to secure the at least one layer of fibre-reinforced aerogel to the combustible heat source.