Treated textile substrate and method for making a textile substrate

Abstract

Compositions and methods for treating textile substrates to obtain superior liquid repellent properties are disclosed. Durable microscopic surface structures imparted to the fibrous substrate allow liquids to bead up and roll off of its surface. Mechanical abrasion or sanding techniques may be used to create the microscopic surface structures on the surface of a fibrous textile substrate, without substantially breaking fibers, followed by a chemical treatment using, for example, fluorocarbon-containing repellent compositions. Particles may be employed in combination with repellent compositions to achieve superior repellent properties. A property of the roughened surface fibers, the Roughness Factor, is used to characterize the microscopic surface structures on the treated textile surface. Treated textile substrates are disclosed which achieve superior water and oil repellency, even after multiple abrasion or laundering cycles.

1 . A woven fiber-containing substrate with a first surface and a second surface having integral microscopic surface structures upon at least a portion of at least one of its surfaces, wherein said integral microscopic surface structures have projections substantially normal to the plane of said fiber-containing substrate, said at least one surface comprised of: 
 (a) portions having a plurality of substantially unbroken fibers comprising surface structures along at least part of the length of said fibers, and wherein said fibers have a Roughness Factor greater than or equal to about 1.10; and    (b) a chemical mixture, said chemical mixture comprising: 
 (i) a fluorocarbon-containing repellent component,  
 (ii) a particulate component, and  
 (iii) a crosslinking component;  
 wherein said woven fiber-containing substrate exhibits substantially durable water repellency following washing, said water repellency being at least about 5 when tested according to the 3M Water Repellency Test II (May 1992).  
   
     
     
         2 . The fiber-containing substrate of  claim 1  wherein said integral microscopic surface structures have a size less than about 100 μm.  
     
     
         3 . The woven fiber-containing substrate of  claim 1  wherein said fluorocarbon-containing repellent component is comprised of a fluoroacrylate material.  
     
     
         4 . The woven fiber-containing substrate of  claim 1  wherein said particulate component is comprised of particles having an average particle size between about 1 nm and about 50 μm.  
     
     
         5 . The woven fiber-containing substrate of  claim 1  wherein said particulate component is comprised of at least one material selected from the group consisting of silicates, doped silicates, minerals, silicas, polymers, carbon, graphite, metal salts, metal powders, silica-coated metal powders, inorganic oxides, and combinations thereof.  
     
     
         6 . The woven fiber-containing substrate of  claim 5  wherein said particulate component is comprised of a silica-based material.  
     
     
         7 . The woven fiber-containing substrate of  claim 6  wherein said silica-based material is colloidal silica.  
     
     
         8 . The woven fiber-containing substrate of  claim 1  wherein said crosslinking component is comprised of a polyurethane-based material.  
     
     
         9 . A method of making a fiber-containing substrate with a first surface and a second surface having integral microscopic surface structures upon at least a portion of at least one of its surfaces, wherein said integral microscopic surface structures have projections substantially normal to the plane of said fiber-containing substrate, said at least one surface comprised of: 
 (i) portions having a plurality of substantially unbroken fibers comprising surface structures along at least part of the length of said fibers, and wherein said fibers have a Roughness Factor greater than or equal to about 1.10;    comprising the steps of:    (a) providing a fiber-containing substrate, said substrate having a first surface and a second surface;    (b) face-finishing at least said first surface of said substrate, thereby forming integral microscopic surface structures upon said first surface; and    (c) applying a chemical mixture to at least said first surface of said substrate, said chemical mixture comprising a repellent component.    
     
     
         10 . The method of  claim 9  wherein said face-finishing of step (b) is achieved by mechanical treatment, chemical treatment, or combinations thereof.  
     
     
         11 . The method of claim  1 Q wherein said face-finishing of step (b) is achieved by mechanical treatment.  
     
     
         12 . The method of  claim 11  wherein said mechanical treatment is accomplished by exposing at least said first surface to one or more abrasive surfaces.  
     
     
         13 . The method of  claim 12  wherein said one or more abrasive surfaces are coated with diamond grit or sandpaper.  
     
     
         14 . The method of  claim 13  wherein said abrasive surfaces are coated with diamond grit having an average grit size of between about 600 and about 1200.  
     
     
         15 . The method of  claim 14  wherein said abrasive surfaces are comprised of one or more abrasive cylindrical rolls.  
     
     
         16 . The method of  claim 9 , wherein said chemical mixture further includes a particulate component.  
     
     
         17 . A method of making a fiber-containing substrate with a first surface and a second surface having integral microscopic surface structures upon at least a portion of at least one of its surfaces, wherein said integral microscopic surface structures have projections substantially normal to the plane of said fiber-containing substrate, said at least one surface comprised of: 
 (i) portions having a plurality of substantially unbroken fibers comprising surface structures along at least part of the length of said fibers, and wherein said fibers have a Roughness Factor greater than or equal to about 1.10;    comprising the steps of:    (a) providing a fiber-containing substrate, said substrate having a first surface and a second surface;    (b) face-finishing at least said first surface of said substrate, thereby forming integral microscopic surface structures upon said first surface;    (c) applying a first chemical mixture to at least said first surface, said first chemical mixture comprising a particulate component; and    (d) subsequently applying a second chemical mixture to at least said first surface, said second chemical mixture comprising a repellent component.    
     
     
         18 . A method of making a fiber-containing substrate with a first surface and a second surface having integral microscopic surface structures upon at least a portion of at least one of its surfaces, wherein said integral microscopic surface structures have projections substantially normal to the plane of said fiber-containing substrate, said at least one surface comprised of: 
 (i) portions having a plurality of substantially unbroken fibers comprising surface structures along at least part of the length of said fibers, and wherein said fibers have a Roughness Factor greater than or equal to about 1.10;    comprising the steps of:    (a) providing a fiber-containing substrate, said substrate having a first surface and a second surface;    (b) face-finishing at least said first surface of said substrate, thereby forming integral microscopic surface structures upon said first surface;    (c) applying a first chemical mixture to at least said first surface, said first chemical mixture comprising a repellent component; and    (d) subsequently applying a second chemical mixture to at least said first surface, said second chemical mixture comprising a repellent component and a particulate component.    
     
     
         19 . A method of making a composite textile substrate comprising the steps of: 
 (a) providing at least one layer of a fiber-containing substrate with a first surface and a second surface having integral microscopic surface structures upon at least a portion of at least one of its surfaces, wherein said integral microscopic surface structures have projections substantially normal to the plane of said fiber-containing substrate, said at least one surface comprised of: 
 (i) portions having a plurality of substantially unbroken fibers comprising surface structures along at least part of the length of said fibers, and wherein said fibers have a Roughness Factor greater than or equal to about 1.10;  
   (b) providing at least one additional layer of material selected from the group consisting of fiber-containing substrates, films, coatings, foams, reinforcing substrates, and adhesives; and    (c) joining the layers of step (a) and step (b) together.    
     
     
         20 . The method of  claim 19  wherein said joining step of (c) is achieved using adhesive, heat lamination, and combinations thereof.