Method for Producing Patterned Nonwovens and Laminated Nonwovens

Abstract

Methods are provided for producing patterned nonwoven materials and patterned laminated multilayer materials which include one or more layers of nonwoven. A nonwoven with heat-activatable binder fibers or binder materials is heated, subjected to patterned pressure. This softens or melts the binder and allows movement of the fibers in the nonwoven according to the pattern pressure. Then, the nonwoven is cooled so that the binder solidifies to lock a durable three-dimensional pattern into the structure. With a multilayer layup, for example, including a substrate layer, an adhesive layer, and a nonwoven layer, the layup is heated to melt the adhesive and soften binder in the nonwoven, then subjected to pattern pressure such as by being pressed with patterned plates, belts, or rollers, and cooled to bond the layers together, and to bond the fibers in the nonwoven according to the pattern pressure so as to fix the pattern. The processes may be carried out in batch mode or continuously using a flatbed laminating machine with heating and cooling zones. Engraved rollers, which may be heated or cooled depending on process conditions, can also be employed. The resulting materials exhibit stable three-dimensional patterns, typically 1-25 mm deep, suitable for functional and aesthetic applications.

1 . A method for producing a patterned nonwoven material, comprising:
 heating a nonwoven material comprising staple fibers together with heat-activatable binder fibers or binder material in the nonwoven structure, wherein the heating softens or melts the heat-activatable binder fibers or binder material allowing the staple fibers to move relative each other in the heated nonwoven material,   applying patterned pressure to the heated nonwoven material in one or more areas to form one or more patterns extending into a thickness of the nonwoven material; and   cooling the nonwoven material so that the binder fibers or binder material solidifies to form the one or more patterns into the one or more areas of a cooled nonwoven material, wherein the cooled nonwoven material has varying thicknesses across its one or more areas which correspond to the applied patterned pressure.   
     
     
         2 . The method of  claim 1 , wherein the patterned pressure is applied by one or more engraved rollers, patterned plates, or patterned belts. 
     
     
         3 . The method of  claim 1 , wherein the method is performed as a continuous process using a flatbed laminating machine comprising a heating zone and cooling zone. 
     
     
         4 . The method of  claim 1 , wherein the nonwoven material comprises a vertically lapped or cross-lapped thermally bonded nonwoven. 
     
     
         5 . The method of  claim 1 , wherein a depth of the three-dimensional pattern in the one or more areas is at least about 1 mm. 
     
     
         6 . The method of  claim 1  wherein a depth of at least portions of the three-dimensional
 pattern in the one or more areas ranges from 1 mm to 25 mm 
 
     
     
         7 . The method of  claim 6  wherein the depth ranges from 5 mm to 15 mm. 
     
     
         8 . A method for producing a patterned laminated multilayer material, comprising:
 preparing a layup comprising:
 at least one side substrate layer, 
 a middle adhesive layer, and 
 another side substrate layer comprising one or more layers of nonwoven material, wherein the nonwoven material comprises staple fibers together with heat-activatable binder fibers or binder material in the nonwoven structure; 
   heating the layup to produce a heated layup, wherein heating melts the middle adhesive layer to form an adhesive suitable for bonding the at least one side substrate layer and the another side substrate layer together, wherein the heating softens or melts the heat-activatable binder fibers or binder material in the one or more layers of nonwoven material so as to allow the staple fibers to move relative each other in the heated nonwoven material;   applying patterned pressure to the heated layup in one or more areas to form one or more patterns extending into a thickness of the layup; and   cooling the layup so that the adhesive bonds the at least one side substrate layer and the another side substrate layer together and so that the binder fibers or binder material solidifies to form the one or more patterns into the one or more areas of a cooled layup, wherein the cooled layup has varying thicknesses across its one or more areas which correspond to the applied patterned pressure.   
     
     
         9 . The method of  claim 8 , wherein the patterned pressure is applied by one or more engraved rollers, patterned plates, or patterned belts. 
     
     
         10 . The method of  claim 8 , wherein the method is performed as a continuous process using a flatbed laminating machine comprising a heating zone and cooling zone. 
     
     
         11 . The method of  claim 8 , wherein the patterned pressure is applied by a heated engraved roller that simultaneously heats, compresses, and patterns the layup, or by a cooled engraved roller when the layup has been preheated. 
     
     
         12 . The method of  claim 8 , wherein the one side substrate layer is selected from the group consisting of knitted fabric, woven fabric, nonwoven fabric, artificial leather, and natural leather. 
     
     
         13 . The method of  claim 8 , wherein a depth of the three-dimensional pattern in the one or more areas is at least about 1 mm. 
     
     
         14 . The method of  claim 8  wherein a depth of at least portions of the three-dimensional pattern in the one or more areas ranges from 1 mm to 25 mm 
     
     
         15 . The method of  claim 14  wherein the depth ranges from 5 mm to 15 mm.