Cigarette Filter Material and Cigarette Filter

Abstract

A cigarette filter material useful for selectively and efficiently reducing formaldehyde while maintaining a palatable component such as nicotine or tar is provided. A cigarette filter material is obtained by adhesively treating a substrate (such as a cellulose acetate fiber) with a dispersion comprising a particulate polysaccharide having an amino group (e.g., chitosan) and a medium. The medium may be a polar solvent (e.g., water, and an alcohol), and a plasticizer for the substrate. A cigarette filter comprising such cigarette filter material can efficiently and selectively reduce formaldehyde. For example, the cigarette filter ensures a retention of formaldehyde of not more than 65% while maintaining retentions of nicotine and tar of not less than 75%, respectively.

1 . A cigarette filter material comprising a substrate and a polysaccharide having an amino group, wherein the polysaccharide is adhered to the substrate, 
 wherein the substrate is treated with a dispersion comprising the polysaccharide and a medium, and the polysaccharide is dispersed in the form of a particle.    
   
   
       2 . A cigarette filter material according to  claim 1 , wherein the material has a filter rod structure and the polysaccharide is a chitosan.  
   
   
       3 . A cigarette filter material according to  claim 2 , wherein, the dispersion comprises the polysaccharide having an average particle size of 0.5 to 50 μm, and the medium comprises at least one member selected from the group consisting of a hydroxyl group-containing solvent and a plasticizer for the substrate.  
   
   
       4 . A cigarette filter material according to  claim 3 , wherein the hydroxyl group-containing solvent is at least one member selected from the group consisting of water and an alcohol, and the plasticizer for the substrate is a lower fatty acid ester of a polyol.  
   
   
       5 . A cigarette filter material according to  claim 1 , wherein the medium contains a polyol as a humectant.  
   
   
       6 . A cigarette filter material according to  claim 5 , wherein the polyol comprises at least one member selected from the group consisting of a C 2-6 alkanediol, a di- to tetraC 2-4 alkylene glycol, and a C 3-10 alkanetriol.  
   
   
       7 . A cigarette filter material according to  claim 6 , wherein the dispersion at least comprises a chitosan having a degree of deacetylation of not less than 70% and an average particle size of 1 to 20 μm, and a C 3-6 alkanetriol.  
   
   
       8 . A cigarette filter material according to  claim 7 , wherein the adhering amount of the polysaccharide is 1 to 100 parts by weight relative to 100 parts by weight of the substrate.  
   
   
       9 . A cigarette filter material according to  claim 8 , wherein the medium resides in the substrate.  
   
   
       10 . A cigarette filter material according to  claim 9 , wherein the residual amount of the medium is 0.5 to 100 parts by weight relative to 100 parts by weight of the substrate.  
   
   
       11 . A cigarette filter material according to  claim 9 , wherein the adhering amount of the polysaccharide is 1 to 80 parts by weight relative to 100 parts by weight of the substrate, and the residual amount of the medium is 5 to 400 parts by weight relative to 100 parts by weight of the polysaccharide.  
   
   
       12 . A cigarette filter material according to  claim 9 , wherein the medium residing in the substrate at least comprises a polyol as a humectant, and the content of the polyol is 3 to 200 parts by weight relative to 100 parts by weight of the polysaccharide.  
   
   
       13 . A process for producing a cigarette filter material recited in  claim 1 , which comprises treating a substrate with a dispersion, wherein the dispersion comprises a particulate polysaccharide having an amino group, and a medium.  
   
   
       14 . A cigarette filter which is made of a cigarette filter material recited in  claim 1 .  
   
   
       15 . (canceled)  
   
   
       16 . A cigarette which comprises a cigarette filter recited in  claim 14.