In situ formation of catalytic cigarette paper

Abstract

Methods for the in situ formation of catalyst particles in cigarette paper are provided. A catalyst precursor, which can be incorporated into the cigarette papermaking process or can be combined with cigarette paper after formation of the paper, can be decomposed to form catalyst particles that are incorporated within the cigarette paper. Cigarette paper comprising the catalyst particles can be used to form a cigarette. During the smoking of a cigarette comprising the catalyst particles the amount of carbon monoxide in the mainstream smoke of the cigarette can be reduced.

What is claimed is: 
     
         1 . Cigarette paper produced by a method comprising (i) supplying a cellulosic material to a first head box of a forming section of a papermaking machine, (ii) depositing an aqueous slurry from the first head box onto the forming section of the papermaking machine so as to form a base web comprising the cellulosic material, (iii) removing water from the base web so as to form an intermediate web, (iv) drying the intermediate web so as to form a finished web, and (v) depositing a catalyst precursor on the finished web to form a catalyst precursor-infiltrated web,
 wherein catalyst particles are formed by thermal decomposition of the catalyst precursor or from a reaction between the catalyst precursor and moisture.   
     
     
         2 . The cigarette paper of  claim 1 , wherein the catalyst precursor comprises iron nitrate, copper nitrate, manganese nitrate, iron ethoxide, iron ethyl hexanoisopropoxide and/or manganese (II) methoxide. 
     
     
         3 . The cigarette paper of  claim 1 , wherein the catalyst precursor comprises a mixture of two or more different catalyst precursor compounds. 
     
     
         4 . The cigarette paper of  claim 1 , wherein the catalyst precursor permeates the finished web. 
     
     
         5 . The cigarette paper of  claim 1 , wherein (a) the catalyst particles have an average particle size of less than about 1 micron or less than about 100 nm, (b) the catalyst particles comprise a metal oxide and/or a metal oxyhydroxide, (c) the catalyst particles comprise an oxide and/or an oxyhydroxide of at least one metal selected from the group consisting of iron, copper and manganese, and/or (d) the catalyst particles are distributed in the paper thickness such that a gradient in the amount of catalyst particles is provided. 
     
     
         6 . The cigarette paper of  claim 1 , wherein (a) the catalyst particles are formed within pores of the fibers of the paper web, (b) the catalyst particles are at least partially enveloped by the paper web, (c) the catalyst particles are formed between fibers and/or fibrils of the paper web, and/or (d) the paper has a basis weight of from about 18 g/m 2  to about 60 g/m 2  and a permeability of from about 5 Coresta units to about 80 Coresta units. 
     
     
         7 . The cigarette paper of  claim 1 , wherein the cigarette paper or tipping paper further comprises a web-filler material, and wherein a ratio, in weight percent, of the catalyst particles to the web-filler material in the first inner wrapper is from about 0.1 to 3.0. 
     
     
         8 . The cigarette paper of  claim 7 , wherein the web-filler material comprises calcium carbonate. 
     
     
         9 . A cigarette comprising a tobacco rod and the cigarette paper of  claim 1 . 
     
     
         10 . The cigarette of  claim 9 , wherein (a) the catalyst precursor is incorporated in the finished web in an amount effective to form the catalyst particles in an amount effective to convert at least 10% of the carbon monoxide in mainstream smoke to carbon dioxide, (b) a paper wrapper of the cigarette comprises the cigarette paper, and/or (c) the cigarette paper is incorporated in the tobacco rod as shredded filler. 
     
     
         11 . The cigarette of  claim 10 , wherein the paper wrapper has a radially inner portion and a radially outer portion, the radially inner portion having a first loading of the catalyst particles and the radially outer portion having a second loading of the catalyst particles, wherein the first loading is greater than the second loading. 
     
     
         12 . The cigarette of  claim 9 , wherein the cigarette paper is a first wrapper and the cigarette further comprises a second wrapper around the first wrapper, wherein the mass of the catalyst particles in the first wrapper is from about 50 to 200 mg, and the mass of the catalyst particles in the second wrapper is less than about 50 mg. 
     
     
         13 . A method of making a cigarette, comprising:
 (i) providing tobacco cut filler to a cigarette making machine to form a tobacco column;   (ii) acing the cigarette paper of  claim 1  around the tobacco column to form a tobacco rod of a cigarette, and   (iii) optionally tipping the tobacco rod with a cigarette filter using tipping paper.