Degradable cellulose acetate tow band comprising a filler

Abstract

Disclosed herein is a tow band comprising cellulose acetate and a filler. The filler may be selected to have a degradation rate greater than that of the cellulose acetate. The tow band may be bloomed and formed into a filter rod, which may then be incorporated into a cigarette filter. The tow, tow band, and filter structures described herein degrade more rapidly than other known tow, tow bands, and filter structures.

We claim: 
     
         1 . A cellulose acetate tow band, the tow band comprising:
 a) cellulose acetate having a degree of substitution (DS) of greater than 1.3; and   b) a filler; wherein the filler has a greater rate of degradation than the cellulose acetate.   
     
     
         2 . The tow band according to  claim 1 , wherein the filler comprises a monosaccharide, polysaccharide, polysaccharide ester, hydrolyzed polysaccharide, oligosaccharide, or combinations thereof 
     
     
         3 . The tow band according to  claim 1 , wherein the filler comprises dextran, a hydrolyzed starch, a modified hydrolyzed starch, hemp, cellulose, or combinations thereof. 
     
     
         4 . The tow band according to  claim 1 , wherein the filler is present from 0.1 to 99.9% by weight, based on the total weight of the tow band. 
     
     
         5 . The tow band according to  claim 1 , wherein the filler is present from 0.1 to 75% by weight, based on the total weight of the tow band. 
     
     
         6 . The tow band according to  claim 1 , wherein the filler is present from 0.1 to 50% by weight, based on the total weight of the tow band. 
     
     
         7 . The tow band according to  claim 1 , wherein the filler is present from 0.1 to 25% by weight, based on the total weight of the tow band. 
     
     
         8 . The tow band according to  claim 1 , wherein the degradation rate of the filler is at least 3% greater than that of the cellulose acetate. 
     
     
         9 . The tow band according to  claim 1 , wherein the degradation rate of the filler is at least 10% greater than that of the cellulose acetate. 
     
     
         10 . The tow band according to  claim 1 , wherein the degradation rate of the filler is at least 15% greater than that of the cellulose acetate. 
     
     
         11 . The tow band according to  claim 1 , wherein the tow band comprises a weight ratio of the cellulose acetate to the filler from 1:99 to 99:1. 
     
     
         12 . The tow band according to  claim 1 , wherein the tow band comprises a weight ratio of the cellulose acetate to the filler from 1:50 to 50:1. 
     
     
         13 . The tow band according to  claim 1 , wherein the tow band comprises a weight ratio of the cellulose acetate to the filler from 1:25 to 25:1. 
     
     
         14 . The tow band according to  claim 1 , wherein the tow band comprises cellulose acetate in an amount from 0.1 to 99.9% by weight, based on the total weight of the tow band. 
     
     
         15 . The tow band according to  claim 1 , wherein the cellulose acetate has a degree of substitution from 2 to 2.9. 
     
     
         16 . The tow band according to  claim 1 , wherein the tow band comprises from 0.01 to 25% by weight additives, based on the total weight of the tow band. 
     
     
         17 . A cigarette filter comprising: a filter element comprising bloomed tow, wherein the bloomed tow comprises the tow band according to  claim 1 . 
     
     
         18 . A method for forming the cigarette filter of  claim 17 , the method comprising
 a) providing the cellulose acetate tow band;   b) blooming the tow band; and   c) forming the bloomed tow band into a filter rod.   
     
     
         19 . The method of  claim 18 , wherein the tow band is formed by:
 a) combining cellulose acetate and the filler with a solvent to form a dope;   b) solvent-spinning the dope to form a plurality of tow filaments; and   c) combining the plurality of tow filaments to form the tow band.   
     
     
         20 . The method of  claim 18 , wherein the tow band is formed by:
 a) combining cellulose acetate and the filler to form a flake;   b) combining the flake with a solvent to form a dope;   c) solvent-spinning the dope to form a plurality of tow filaments; and   d) combining the plurality of tow filaments to form the tow band.