Antimicrobially-treated fabrics

Abstract

A method for forming an antimicrobially-treated fabric is provided. The method includes forming a solution from a liquid and an antimicrobial agent, such as 3-(trimethoxysilyl)propyloctadecyldimethyl ammonium chloride. In one embodiment, a cellulosic fibrous material is combined with the solution while in the pulper to form a liquid suspension such that the antimicrobial agent becomes substantive to the cellulosic fibrous material. A web is formed from the antimicrobially-treated cellulosic fibrous material such that substantially all of the cellulosic fibrous material present within the web is derived from the antimicrobially-treated cellulosic fibrous material. In one embodiment, the web of antimicrobially-treated fibrous material is also hydraulically entangled with a nonwoven substrate. In some embodiments, when dried, the antimicrobial agent forms a covalent bond with the cellulosic fibrous material.

What is claimed is:  
     
         1 . A method for forming an antimicrobially-treated fabric, said method comprising: 
 forming a solution from a liquid and an antimicrobial agent;    combining a cellulosic fibrous material with said solution to form a liquid suspension, wherein said antimicrobial agent becomes substantive to said cellulosic fibrous material after being combined therewith; and    forming a web from said liquid suspension of said antimicrobially-treated cellulosic fibrous material such that substantially all of the cellulosic fibrous material present within said web is derived from said antimicrobially-treated cellulosic fibrous material.    
     
     
         2 . A method as defined in  claim 1 , wherein at least a portion of said liquid from said liquid suspension is removed during formation of said web, said removed liquid portion being substantially free from said antimicrobial agent.  
     
     
         3 . A method as defined in  claim 1 , wherein said antimicrobial agent is an organosilicone quaternary ammonium compound.  
     
     
         4 . A method as defined in  claim 3 , wherein said organosilicone quaternary ammonium compound has the following structure:  
       
         
           
           
               
               
           
         
       
       wherein, 
 R 1  is hydrogen or a C 1 -C 8  alkyl group;  
 R 2  is hydrogen or a C 1 -C 8  alkyl group;  
 R 3  and R 4  are the same or different, and are selected from the group consisting of hydrogen and a C 1 -C 4  alkyl group;  
 R 5  is hydrogen or a C 1 -C 30  alkyl group; and  
 X −  is a suitable counterion.  
 
     
     
         5 . A method as defined in  claim 1 , wherein said antimicrobial agent is 3-(trimethoxysilyl)propyloctadecyldimethyl ammonium chloride.  
     
     
         6 . A method as defined in  claim 1 , wherein said antimicrobial agent is hydrolyzed prior to forming said solution.  
     
     
         7 . A method as defined in  claim 1 , wherein said solution and said cellulosic fibrous material are combined in a pulper.  
     
     
         8 . A method as defined in  claim 7 , wherein said solution and said cellulosic fibrous material are subjected to agitation while in said pulper.  
     
     
         9 . A method as defined in  claim 1 , wherein said antimicrobial agent is present in an amount between about 0.04% to about 1.0% by weight of said antimicrobially-treated cellulosic fibrous material.  
     
     
         10 . A method as defined in  claim 1 , wherein said antimicrobial agent is present in an amount between about 0.2% to about 0.5% by weight of said antimicrobially-treated cellulosic fibrous material.  
     
     
         11 . A method as defined in  claim 1 , wherein said cellulosic fibrous material comprises high-average length pulp fibers, low-average length pulp fibers, or mixtures thereof.  
     
     
         12 . A method as defined in  claim 1 , further comprising hydraulically entangling said web of antimicrobially-treated fibrous material with a nonwoven substrate.  
     
     
         13 . A method as defined in  claim 12 , wherein said nonwoven substrate is formed from continuous filaments.  
     
     
         14 . A method as defined in  claim 13 , wherein said continuous filaments are formed by a spunbond process.  
     
     
         15 . A method as defined in  claim 1 , further comprising drying said web so that said antimicrobial agent forms a covalent bond with said cellulosic fibrous material.  
     
     
         16 . A method as defined in  claim 15 , wherein said antimicrobial agent is an organosilicone compound such that said covalent bond is a siloxane bond.  
     
     
         17 . A method for forming an antimicrobially-treated fabric, said method comprising: 
 forming a solution from a liquid and an antimicrobial agent, said antimicrobial agent being an organosilicone quaternary ammonium compound;    combining pulp fibers with said solution to form a liquid suspension while under agitation, wherein said organosilicone quaternary ammonium compound becomes substantive to said pulp fibers after being combined therewith;    forming a web from said liquid suspension of said antimicrobially-treated cellulosic fibrous material such that substantially all of the cellulosic fibrous material present within said web is derived from said antimicrobially-treated cellulosic fibrous material    hydraulically entangling said web of antimicrobially-treated pulp fibers with a nonwoven substrate; and    drying said web so that said antimicrobial agent forms a covalent bond with pulp fibers.    
     
     
         18 . A method as defined in  claim 17 , wherein said covalent bond is a siloxane bond.  
     
     
         19 . A method as defined in  claim 17 , wherein at least a portion of said liquid from said liquid suspension is removed during formation of said web, said removed liquid portion being substantially free from said antimicrobial agent.  
     
     
         20 . A method as defined in  claim 17 , wherein said organosilicone quaternary ammonium compound has the following structure:  
       
         
           
           
               
               
           
         
       
       wherein, 
 R 1  is hydrogen or a C 1 -C 8  alkyl group;  
 R 2  is hydrogen or a C 1 -C 8  alkyl group;  
 R 3  and R 4  are the same or different, and are selected from the group consisting of hydrogen and a C 1 -C 4  alkyl group;  
 R 5  is hydrogen or a C 1 -C 30  alkyl group; and  
 X −  is a suitable counterion.  
 
     
     
         21 . A method as defined in  claim 17 , wherein said antimicrobial agent is 3-(trimethoxysilyl)propyloctadecyldimethyl ammonium chloride.  
     
     
         22 . A method as defined in  claim 17 , wherein said solution and said pulp fibers are combined in a pulper.  
     
     
         23 . A method as defined in  claim 17 , wherein said nonwoven substrate is formed from continuous filaments.  
     
     
         24 . A method as defined in  claim 23 , wherein said continuous filaments are formed by a spunbond process.  
     
     
         25 . An antimicrobially-treated composite fabric comprising a nonwoven continuous filament substrate hydraulically entangled with pulp fibers, wherein substantially all of the pulp fibers present within the composite material are treated with an organosilicone antimicrobial agent.  
     
     
         26 . An antimicrobially-treated composite fabric as defined in  claim 25 , wherein said antimicrobial agent is an organosilicone quaternary ammonium compound.  
     
     
         27 . An antimicrobially-treated composite fabric as defined in  claim 25 , wherein said organosilicone quaternary ammonium compound has the following structure:  
       
         
           
           
               
               
           
         
       
       wherein, 
 R 1  is hydrogen or a C 1 -C 8  alkyl group;  
 R 2  is hydrogen or a C 1 -C 8  alkyl group;  
 R 3  and R 4  are the same or different, and are selected from the group consisting of hydrogen and a C 1 -C 4  alkyl group;  
 R 5  is hydrogen or a C 1 -C 30  alkyl group; and  
 X −  is a suitable counterion.  
 
     
     
         28 . An antimicrobially-treated composite fabric as defined in  claim 25 , wherein said antimicrobial agent is 3-(trimethoxysilyl)propyloctadecyldimethyl ammonium chloride.  
     
     
         29 . An antimicrobially-treated composite fabric as defined in  claim 25 , wherein said organosilicone antimicrobial agent comprises between about 0.04% to about 1.0% by weight of said pulp fibers.  
     
     
         30 . An antimicrobially-treated composite fabric as defined in  claim 25 , wherein said organosilicone antimicrobial agent comprises between about 0.2% to about 0.5% by weight of said pulp fibers.  
     
     
         31 . An antimicrobially-treated composite fabric as defined in  claim 25 , wherein said continuous filaments are formed by a spunbond process.  
     
     
         32 . An antimicrobially-treated composite fabric as defined in  claim 25 , wherein said pulp fibers comprises between about 60% to about 90% by weight of said composite fabric.  
     
     
         33 . An antimicrobially-treated composite fabric as defined in  claim 25 , wherein said organosilicone antimicrobial agent comprises between about 0.03% to about 0.8% by weight of said composite fabric.  
     
     
         34 . An antimicrobially-treated composite fabric as defined in  claim 25 , wherein said organosilicone antimicrobial agent comprises between about 0.16% to about 0.4% by weight of said composite fabric.  
     
     
         35 . An antimicrobially-treated composite fabric as defined in  claim 25 , wherein said organosilicone antimicrobial agent is covalently bonded to said pulp fibers.  
     
     
         36 . An antimicrobially-treated composite fabric as defined in  claim 35 , wherein the covalent bond formed between said organosilicone antimicrobial agent and said pulp fibers is a siloxane bond.