Method and apparatus for preparing a slurry of add-on material to be applied to a web

Abstract

A method of producing a slurry of material effective for application to designated regions on cigarette paper to affect the burn rate in the designated regions, includes the steps of cooking a fibrous cellulosic material, bleaching the material, pressing the cooked and bleached material to remove liquid, drying the pressed material, milling the dried material to produce fibers of a desired size and mixing the milled material with water. Flax straw can be used as one source of the fibrous cellulosic material, and can be subjected to a hammering process for removal of non-fibrous components of the flax straw and for reduction in the fiber size before the cooking of the fibrous cellulosic material.

1 . A method of manufacturing a web having an applied pattern of add-on material, said method comprising: 
 moving a base web along a first path;    preparing a slurry of add-on material; and    repetitively discharging said slurry of add-on material upon said moving base web, said step of preparing a slurry of add-on material including: 
 cooking a fibrous cellulosic material,  
 bleaching the material,  
 pressing the cooked and bleached material to remove liquid,  
 drying the pressed material,  
 milling the dried material to produce fibers of a desired size, and  
 mixing the milled material with water to hydrate the material and produce a slurry.  
   
     
     
         2 . The method according to  claim 1 , wherein said step of repetitively discharging said add-on slurry comprises: 
 continuously moving a belt having an orifice along an endless path, said belt moving step including the step of moving said belt along a first portion of said endless path where said orifice is communicated with a reservoir so as to discharge said add-on slurry from said reservoir through said orifice onto said base web as said orifice traverses said first path portion.    
     
     
         3 . The method according to  claim 1 , wherein said fibrous cellulosic material comprises flax straw feed stock.  
     
     
         4 . The method according to  claim 3  further including: 
 subjecting the flax straw feed stock to a process for removing non-fibrous component including shive before the step of cooking the fibrous cellulosic material.    
     
     
         5 . The method according to  claim 4 , wherein the process for removing the non-fibrous component is preformed in a hammer mill.  
     
     
         6 . A method of producing a slurry of fibrous cellulosic material effective for application to designated regions on cigarette paper to affect the burn rate of the cigarette paper in the designated regions, the method comprising: 
 cooking a fibrous cellulosic material;    bleaching the material;    pressing the cooked and bleached material to remove liquid;    drying the pressed material;    milling the dried material to produce fibers of a desired size; and    mixing the milled material with water to hydrate the material and produce a slurry of the material.    
     
     
         7 . The method according to  claim 6 , wherein the fibrous cellulosic material is produced from flax straw.  
     
     
         8 . The method according to  claim 7  further including: 
 subjecting the flax straw to a process for removing non-fibrous component including shive before the step of cooking the fibrous cellulosic material.    
     
     
         9 . The method according to  claim 8 , wherein the process for removing the non-fibrous component is preformed in a hammer mill.  
     
     
         10 . A method of processing feed stock to produce a fibrous cellulosic material having a narrow range of fiber sizes suitable for application to designated regions on cigarette paper, the method comprising: 
 subjecting the feed stock to a hammering process for removal of non-fibrous components from the feed stock;    cooking the processed feed stock;    bleaching the feed stock;    pressing the cooked and bleached feed stock to remove liquid;    drying the pressed feed stock, and    milling the dried feed stock to produce the fibrous cellulosic material having a narrow range of fiber sizes.    
     
     
         11 . The method according to  claim 10 , wherein the feed stock is derived from flax straw.  
     
     
         12 . The method according to  claim 10 , further including the steps of blending the milled feed stock with water to hydrate the feed stock and produce a slurry, and passing the slurry through a double-disk refiner.  
     
     
         13 . A system for processing feed stock to produce a fibrous cellulosic material having a narrow range of fiber sizes suitable for application to designated regions on cigarette paper, the system comprising: 
 a station at which a cellulosic feed stock is cooked;    a station at which the feed stock is bleached;    a press that presses the cooked and bleached feed stock to remove liquid;    a station at which the pressed feed stock is dried; and    a grinding machine that grinds the dried feed stock to produce the fibrous cellulosic material having a narrow range of fiber sizes.    
     
     
         14 . The system according to  claim 13 , wherein: 
 the grinding machine grinds the feed stock until the weighted average fiber length is in the range from approximately 0.5 to 1 mm.    
     
     
         15 . The system according to  claim 14 , wherein: 
 the grinding machine grinds the feed stock until the weighted average fiber length is approximately 1 mm.    
     
     
         16 . The system according to  claim 13 , further including: 
 a station at which the feed stock is hammered to remove non-fibrous components before being passed to the station at which the feedstock is cooked.    
     
     
         17 . The system according to  claim 16 , wherein: 
 the grinding machine grinds the feed stock until the weighted average fiber length is in the range from approximately 0.5 to 1 mm.    
     
     
         18 . The system according to  claim 17 , wherein: 
 the grinding machine grinds the feed stock until the weighted average fiber length is approximately 1 mm.    
     
     
         19 . The system according to  claim 13 , further including: 
 a station at which the ground feed stock is blended with water to hydrate the feed stock and produce a slurry.    
     
     
         20 . The system according to  claim 19 , further including: 
 a double-disk refiner through which the slurry is passed before being applied to the designated regions on cigarette paper.    
     
     
         21 . The system according to  claim 20 , wherein: 
 the grinding machine grinds the feed stock until the weighted average fiber length is in the range from approximately 0.5 to 1 mm.    
     
     
         22 . The system according to  claim 21 , wherein: 
 the grinding machine grinds the feed stock until the weighted average fiber length is approximately 1 mm.