Cigarettes having hollow fibers

Abstract

Smoking articles, such as cigarettes and cigarette filters, methods of manufacturing smoking articles including hollow fibers, and methods of smoking are provided. In one exemplary embodiment, a smoking article contains hollow fibers, wherein the hollow fibers change properties of mainstream tobacco smoke drawn through the hollow fibers.

1 . A cigarette, comprising: 
 a tobacco rod;    a filter operative with the tobacco rod, wherein the filter comprises a bundle of hollow fibers, wherein the lumens of the hollow fibers are aligned axially in parallel to one another; and    an additive material in extra-cellular spaces of the hollow fibers,    wherein one end of at least one of the hollow fibers is obstructed.    
   
   
       2 . The cigarette of  claim 1 , wherein the filter further comprises a plug of fibrous filter material, wherein the plug is located upstream and/or downstream from the hollow fibers in the filter.  
   
   
       3 . The cigarette of  claim 1 , wherein the hollow fibers are located in a cavity of the filter.  
   
   
       4 . The cigarette of  claim 1 , wherein the obstructed end of the at least one of the hollow fibers comprises a first smoke impermeable material located within the lumen of the at least one of the hollow fibers, wherein the impermeable material obstructs airflow through the obstructed end of the at least one of the hollow fibers.  
   
   
       5 . The cigarette of  claim 4 , wherein the first smoke impermeable material comprises a polymer or a composite.  
   
   
       6 . The cigarette of  claim 1 , further comprising a second smoke impermeable material surrounding an upstream or a downstream end of the bundle of hollow fibers, wherein the second smoke impermeable material obstructs airflow around the bundle of hollow fibers and directs airflow into lumens of the bundle of hollow fibers.  
   
   
       7 . The cigarette of  claim 6 , wherein the first smoke impermeable material comprises a polymer or a composite.  
   
   
       8 . The cigarette of  claim 1 , further comprising an outer layer on the hollow fibers, wherein the outer layer and the hollow fibers comprise different materials.  
   
   
       9 . The cigarette of  claim 8 , wherein the outer layer comprises sugar or pectin.  
   
   
       10 . The cigarette of  claim 1 , wherein the hollow fibers comprise a polymeric material.  
   
   
       11 . The cigarette of  claim 1 , wherein the hollow fibers comprise cellulose, modified cellulose, cellulose acetate, polypropylene, polysulfone, acrylic compounds, silicone rubber, or mixtures or combinations thereof.  
   
   
       12 . The cigarette of  claim 1 , wherein the additive material comprises a flavorant, a reagent which chemically reacts with and selectively separates a gaseous component of a smoke stream, a surfactant, a solvent, or mixtures or combinations thereof.  
   
   
       13 . The cigarette of  claim 12 , wherein the additive material comprises menthol.  
   
   
       14 . The cigarette of  claim 1 , wherein the hollow fibers comprise a bundle of fibers, and wherein the cigarette further comprises a ring, wherein the ring surrounds the bundle of fibers.  
   
   
       15 . The cigarette of  claim 1 , wherein the hollow fibers comprises a bundle of fibers, and wherein the cigarette further comprises an adhesive, wherein the adhesive bonds walls of the bundle of fibers to other walls of the bundle of fibers.  
   
   
       16 . The cigarette of  claim 1 , wherein each of the hollow fibers has a lumen diameter of approximately 50 microns to approximately 1500 microns.  
   
   
       17 . The cigarette of  claim 1 , wherein each of the hollow fibers has a lumen an inner diameter of approximately 90 microns to approximately 450 microns.  
   
   
       18 . The cigarette of  claim 1 , wherein the filter further comprises a sorbent.  
   
   
       19 . The cigarette of  claim 18 , wherein the sorbent is located upstream in the filter from the hollow fibers.  
   
   
       20 . The cigarette of  claim 1 , wherein the lumens of the hollow fibers are aligned with one another in a direction in which smoke will travel through the cigarette.  
   
   
       21 . A cigarette filter, comprising: 
 hollow fibers;    an outer layer covering an outer region of the hollow fibers; and    cellulose acetate, wherein the hollow fibers and the outer layer are embedded within the cellulose acetate.    
   
   
       22 . The cigarette filter of  claim 21 , further comprising an additive material in extra-cellular spaces in the hollow fibers.  
   
   
       23 . The cigarette filter of  claim 22 , wherein the additive material comprises a flavorant, a reagent which chemically reacts with and selectively separates a gaseous component of a smoke stream, a surfactant, a solvent, or mixtures or combinations thereof.  
   
   
       24 . The cigarette filter of  claim 22 , further comprising a first smoke impermeable material located between outer surfaces of the hollow fibers and the inner diameter of the cigarette filter on one end of at least one of the hollow fibers, and a second smoke impermeable material located on end portions of lumens of the hollow fibers at the other end of the hollow fibers.  
   
   
       25 . The cigarette filter of  claim 22 , wherein the outer layer comprises sugar or pectin.  
   
   
       26 . A method of manufacturing a cigarette filter, comprising: 
 preparing hollow fibers with a smoke impermeable material covering one end of at least one of the hollow fibers;    at least partially filling extra-cellular spaces within the hollow fibers with an additive material; and    placing the hollow fibers with the smoke impermeable material and the additive material in a cigarette filter.    
   
   
       27 . The method of  claim 26 , wherein the at least partially filling the extra-cellular spaces within the hollow fibers with the additive material comprises soaking the hollow fibers in the additive material for a time effective to at least partially fill the extra-cellular spaces with the additive material.  
   
   
       28 . The method of  claim 26 , further comprising forming an outer layer on an outer surface of the hollow fibers before placing the hollow fibers in the cigarette filter.  
   
   
       29 . The method of  claim 28 , wherein the forming of the outer layer comprises spraying a layer of pectin or sugar on the outer surface of the hollow fibers.  
   
   
       30 . A method of treating mainstream smoke, comprising: 
 drawing tobacco smoke axially through hollow fibers, wherein the mainstream tobacco smoke is drawn into an open upstream end into lumens of the hollow fibers and is drawn through permeable walls of the hollow fibers to a downstream end of a smoking article.    
   
   
       31 . A cigarette filter comprising a hollow fiber membrane, wherein the hollow fiber membrane comprises: 
 hollow fibers; and    a smoke impermeable material, wherein the smoke impermeable material obstructs a downstream end of a lumen of the hollow fiber.    
   
   
       32 . The cigarette filter of  claim 31 , wherein the hollow fiber membrane comprises more than one hollow fiber bundled and aligned in a direction parallel to one another and parallel to an axial direction of the cigarette filter, and/or wherein the hollow fiber comprises a porous, permeable material.  
   
   
       33 . The cigarette filter of  claim 31 , further comprising an additive material in extra-cellular spaces of the hollow fibers.  
   
   
       34 . The cigarette filter of  claim 33 , wherein the additive material comprises a flavorant, a reagent which chemically reacts with and selectively separates a gaseous component of a smoke stream, a surfactant, a solvent, or mixtures thereof.