Magnetic filter elements and cigarettes having magnetic filter elements

Abstract

A magnetic cigarette filter element is provided comprising a filter material and at least one magnetic substrate. The magnetic substrate can comprise at least one monolithic ferromagnetic substrate in the shape of a disc, ring, ribbon, mesh, rod, cylinder and/or spheroid that is incorporated in, on and/or around the filter rod. The magnetic substrate can filter (i.e., magnetically attract and trap) ferromagnetic particles from the mainstream smoke of a cigarette comprising the magnetic cigarette filter.

1 . A filter element adapted to be incorporated into a filter cigarette wherein the filter element comprises a filter material and at least one magnetic substrate.  
   
   
       2 . The filter element of  claim 1 , wherein the at least one magnetic substrate is selected from the group consisting of a disc, ring, ribbon, mesh, rod, cylinder and spheroid and has at least one dimension of greater than about 1 mm or greater than about 2 mm.  
   
   
       3 . The filter element of  claim 1 , wherein the at least one magnetic substrate consists essentially of a ferrite magnet, a neodymium iron boron magnet, a samarium cobalt magnet, an aluminum nickel cobalt magnet or an electromagnet.  
   
   
       4 . The filter element of  claim 1 , wherein the at least one magnetic substrate comprises sintered material which is at least 50% dense or at least 90% dense.  
   
   
       5 . The filter element of  claim 1 , wherein the at least one magnetic substrate has a Curie temperature of at least about 300° C. and/or a magnetic field strength effective to attract ferromagnetic and/or nanoscale particles being carried by the mainstream smoke of a cigarette comprising the filter element.  
   
   
       6 . The filter element of  claim 1 , wherein the filter material is wrapped in plug wrap and the at least one magnetic substrate is a ring disposed on an inner surface of the plug wrap.  
   
   
       7 . The filter element of  claim 1 , wherein the at least one magnetic substrate is (a) incorporated in the filter material (b) is non-homogeneously dispersed throughout the filter material, and/or (c) is formed at least partially around the filter material.  
   
   
       8 . The filter element of  claim 1 , wherein the filter material is wrapped in plug wrap and the at least one magnetic substrate is disposed on an inner surface of the plug wrap and/or the at least one magnetic substrate is adhered to an inner surface of the plug wrap with an adhesive.  
   
   
       9 . The filter element of  claim 1 , wherein the at least one magnetic substrate is incorporated into one or more filter parts selected from the group consisting of a shaped paper insert, a plug, a space between plugs, cigarette filter paper, a cellulose acetate sleeve, a polypropylene sleeve and a free-flow sleeve.  
   
   
       10 . The filter element of  claim 1 , wherein the resistance to draw through the filter element is less than about 5 inches of water at an air flow velocity of about 1050 cc/min.  
   
   
       11 . The filter element of  claim 1 , wherein the filter element comprises a mono filter, a dual filter, a triple filter, a cavity filter, a recessed filter, a free-flow filter or combinations thereof, wherein the filter material is selected from the group consisting of cellulose ester fibers, regenerated cellulose, polyamide fibers, polyimide fibers, acrylic fibers, polyester fibers, polycarbonate fibers, polyethylene fibers, polyvinyl chloride fibers, filamentary polyolefin materials, polypropylene fibers, wood pulp fibers, cotton, flax, jute, wool, silk, ramie, protein fibers, paper and mixtures thereof.  
   
   
       12 . The filter element of  claim 1 , wherein the filter element further comprises at least one additive, wherein the additive is selected from the group consisting of an adsorbent, flavorant and catalyst.  
   
   
       13 . A cigarette comprising the filter element of  claim 1 .  
   
   
       14 . The cigarette of  claim 13 , wherein the at least one magnetic substrate is adapted to reduce the amount of ferromagnetic particles entrained in the mainstream smoke of the cigarette by at least 10% and/or to change the chemical composition of mainstream smoke that flows through the filter element.  
   
   
       15 . The cigarette of  claim 13 , wherein the cigarette comprises a tobacco rod wrapped in cigarette paper, said tobacco rod attached to the filter element with tipping paper, and the at least one magnetic substrate is incorporated axially between the filter material and the tobacco rod.  
   
   
       16 . The cigarette of  claim 15 , wherein the tobacco rod and/or cigarette paper further comprises nanoscale and/or ferromagnetic particles.  
   
   
       17 . A method of making a cigarette filter element comprising at least one magnetic substrate, comprising: 
 providing a filter material and plug wrap material;    forming the filter material into a filter rod;    incorporating the at least one magnetic substrate in and/or on at least one of the filter rod and plug wrap material; and    wrapping the filter rod in the plug wrap material to form the filter element.    
   
   
       18 . The method of  claim 17 , wherein the magnetic substrate is incorporated in the filter material prior to forming the filter material into the filter rod.  
   
   
       19 . The method of  claim 17 , comprising forming the at least one magnetic substrate (a) at least partially around the filter rod prior to wrapping the filter rod in the plug wrap, (b) on an exterior surface of the filter rod prior to wrapping the filter rod in the plug wrap, and/or (c) on an interior surface of the plug wrap prior to wrapping the filter rod in the plug wrap.