Cellulosic substrates with reduced absorbent capacity having the capability to wick liquids

Abstract

The present invention relates to cellulosic substrates with reduced absorbent capacity having the capability to wick liquids, as well as to methods of manufacturing such cellulosic substrates. The cellulosic substrates provided by the present invention comprise an inside and an outside connected to the inside. The inside comprises cellulosic fibers and has a reduced absorbent capacity, and the outside comprises cellulosic fibers. The outside may have a reduced absorbent capacity and may have an absorbent capacity higher than the inside. The cellulosic substrate is capable of wicking liquid contacting the inside of the substrate to the outside of the substrate.

That which is claimed is:  
     
         1 . A method of forming a knit or woven fabric comprising the steps of: 
 (a) providing a first yarn comprising cellulosic fibers, at least a portion of the cellulosic fibers being treated with a hydrophobic treatment;    (b) providing a second yarn comprising cellulosic fibers and having a higher absorbent capacity than the first yarn;    (c) forming a fabric having an inside surface and an outside surface by knitting or weaving the first and second yarns such that the inside surface has a lower absorbent capacity than the outside surface, the inside surface has a discontinuous hydrophobicity, and the fabric has channels of hydrophilic fibers for wicking liquid contacting the inside surface of the fabric to the outside surface of the fabric.    
     
     
         2 . The method of  claim 1  wherein: 
 the first yarn is formed from a blend of cellulosic fibers treated with a hydrophobic treatment and cellulosic fibers not treated with a hydrophobic treatment;  
 the second yarn is formed either from cellulosic fibers not treated with a hydrophobic treatment or from a blend of cellulosic fibers treated with a hydrophobic treatment and cellulosic fibers not treated with a hydrophobic treatment, the ratio of treated fibers to untreated fibers in the second yarn being lower than the ratio of treated fibers to untreated fibers in the first yarn; and  
 the inside surface comprises the first yarn and the outside surface comprises the second yarn.  
 
     
     
         3 . The method of  claim 2  wherein the ratio of treated fibers to untreated fibers in the first yarn is from 99:1 to 10:90.  
     
     
         4 . The method of  claim 1  wherein: 
 the first yarn is treated with a hydrophobic treatment;  
 the second yarn is not treated with a hydrophobic treatment;  
 the inside surface is formed from the first and second yarns;  
 the outside surface is formed from the first and second yarns; and  
 the first yarn is present on the outside surface of the fabric in a lower amount than on the inside surface of the fabric or is not present on the outside surface of the fabric.  
 
     
     
         5 . The method of  claim 4  wherein the first yam has been subjected to a discontinuous hydrophobic treatment.  
     
     
         6 . The method of  claim 4  wherein the ratio of the second yarn to the first yam on the outside surface is from 99:1 to 10:90.  
     
     
         7 . The method of  claim 1  wherein the inside surface and the outside surface consist of cellulosic fibers.  
     
     
         8 . The method of  claim 1  wherein the cellulosic fibers of the first and second yams are cotton fibers.  
     
     
         9 . The method of  claim 1  wherein the cellulosic fibers of the first and second yams are selected from the group consisting of cotton, jute, flax, hemp, ramie, iyoceii, rayon, and blends thereof.  
     
     
         10 . A method of forming a knit or woven fabric comprising the steps of: 
 (a) providing a knit or woven fabric having an inside surface and an outside surface, the fabric comprising one or more yams formed from cellulosic fibers; and    (b) applying a hydrophobic treatment material to the inside surface of the fabric in a discontinuous manner such that the inside surface of the fabric has a lower absorbent capacity than the outside surface, the inside surface has a discontinuous hydrophobicity, and the fabric has channels of hydrophilic fibers for wicking liquid contacting the inside surface of the fabric to the outside surface of the fabric.    
     
     
         11 . The method of  claim 10  wherein the inside surface and the outside surface consist of cellulosic fibers.  
     
     
         12 . The method of  claim 10  wherein the cellulosic fibers of the one or more yarns are cotton fibers.  
     
     
         13 . The method of  claim 10  wherein the hydrophobic treatment material is selected from the group consisting of silicones, fluorochemicals, zirconium compounds, oils, latexes, waxes, crosslinking resins, and blends thereof.  
     
     
         14 . The method of  claim 10  wherein the cellulosic fibers of the one or more yarns are selected from the group consisting of cotton, jute, flax, hemp, ramie, lyocell, rayon, and blends thereof.  
     
     
         15 . A method of forming a knit or woven fabric comprising the steps of: 
 (a) providing a knit or woven fabric having an inside surface and an outside surface, the fabric comprising one or more yarns formed from cellulosic fibers, the inside surface having a discontinuous resist;    (b) applying a hydrophobic treatment material to the inside surface of the fabric in a continuous manner, wherein the hydrophobic treatment material does not bond to the resist; and    (c) removing the resist from the fabric to form a fabric wherein the inside surface has a lower absorbent capacity than the outside surface, the inside surface has a discontinuous hydrophobicity, and the fabric has channels of hydrophilic fibers for wicking liquid contacting the inside surface of the fabric to the outside surface of the fabric.    
     
     
         16 . The method of  claim 15  wherein the discontinuous resist of the inside surface of the fabric provided in step (a) is formed by using one or more yams made from a blend of raw cotton and scoured or scoured and bleached cotton.  
     
     
         17 . The method of  claim 15  wherein the discontinuous resist of the inside surface of the fabric provided in step (a) is formed by subjecting one or more of the yarns or a portion of one or more of the yarns used to form the fabric to a resist treatment before the fabric is formed.  
     
     
         18 . The method of  claim 15  wherein the discontinuous resist of the inside surface of the fabric provided in step (a) is formed by subjecting the inside surface of the fabric to a discontinuous resist treatment after the fabric is formed.  
     
     
         19 . The method of  claim 15  wherein the hydrophobic treatment material is selected from the group consisting of silicones, fluorochemicals, zirconium compounds, oils, latexes, waxes, crosslinking resins, and blends thereof.  
     
     
         20 . A method of forming a knit or woven fabric comprising the steps of: 
 (a) providing a knit or woven fabric having an inside surface and an outside surface, the fabric comprising one or more yarns formed from cellulosic fibers;    (b) applying a hydrophobic treatment material to the inside surface of the fabric in a continuous manner such that the inside surface of the fabric has a lower absorbent capacity than the outside surface; and    (c) forming channels of hydrophilic fibers in the fabric for wicking liquid contacting the inside surface of the fabric to the outside surface of the fabric such that the inside surface has a discontinuous hydrophobicty.    
     
     
         21 . The method of  claim 20  wherein the channels are formed by needle punching or hydroentangling.