Layered reinforced product based on non-woven fabric, particularly for bituminization, and method for producing the product

Abstract

A reinforced layered product based on non-woven fabric, which comprises: at least one first ply of non-woven fabric made of polyester fibers predominantly orientated along a predefined direction; at least one second ply chosen between a non-woven fabric made of polyester fibers that are predominantly orientated at right angles to the at least one first ply and melt at a lower temperature, and a layer of a hot-melt adhesive; at least one third ply of non-woven fabric made of polyester fibers predominantly orientated along the direction of predominant orientation of the at least one first ply; at least one net of glass fibers arranged between two plies having different orientations selected among the at least one first ply, the at least one second ply, and the at least one third ply the fibers of the at least one second ply or of the layer of hot-melt adhesive being bonded by heat with the other plies that are in contact with them, the entire assembly being consolidated by means of resin.

What is claimed is:  
     
         1 . A reinforced layered product based on non-woven fabric, comprising: 
 at least one first ply of non-woven fabric made of polyester fibers predominantly orientated along a predefined direction;    at least one second ply chosen between a non-woven fabric made of polyester fibers that are predominantly orientated at right angles to said at least one first ply and melt at a lower temperature, and a layer of a hot-melt adhesive that melts at a lower temperature;    at least one third ply of non-woven fabric made of polyester fibers predominantly orientated along the direction of predominant orientation of said at least one first ply;    at least one net of glass fibers arranged between two plies having different orientations selected among said at least one first ply    said at least one second ply, and said at least one third ply, the fibers of said at least one first ply and of said at least one third ply being bonded by heat    to the fibers of said at least one second ply that are in contact with them, when said second ply is constituted by a non-woven fabric made of polyester fibers;    to said layer of a hot-melt adhesive, when said at least one second ply is constituted by said layer of adhesive    the entire assembly being consolidated by means of resin.    
     
     
         2 . The reinforced layered product based on non-woven fabric according to  claim 1 , wherein said at least one first ply and said at least one third ply have substantially a count of 4.4 dtex, a size of 76 mm, a weight of 45 g/m 2 , and a melting temperature of approximately 255° C.  
     
     
         3 . The reinforced layered product based on non-woven fabric according to  claim 1 , wherein said at least one second ply of non-woven fabric made of polyester fiber substantially has a count of 4.4-6.7 dtex, a size of 76 mm, a weight of 10 g/m 2 , and a melting temperature of approximately 234° C.  
     
     
         4 . The reinforced layered product based on non-woven fabric according to  claim 1 , wherein said layer of a hot-melt adhesive is based on at least one among polyester, polyurethane, acrylates and the like.  
     
     
         5 . The reinforced layered product based on non-woven fabric according to  claim 1 , wherein said net of glass fibers has a weight of approximately 8 g/m 2 .  
     
     
         6 . The reinforced layered product based on non-woven fabric according to  claim 1 , wherein said glass fiber net has a warp count of 340 dtex and 1.6 filaments per cm and a weft count of 340 dtex, and 0.4 filaments per cm, the entire system being adhesive-bonded by means of polyvinyl alcohol.  
     
     
         7 . The reinforced layered product based on non-woven fabric according to  claim 1 , wherein said resin is present in an amount approximately equal to 10% by weight of the total.  
     
     
         8 . A method for producing a reinforced layered product based on non-woven fabric comprising the steps of: 
 feeding a carding machine that is orientated transversely to an advancement direction of a product with at least one first ply and at least one third ply of non-woven fabric made of polyester fibers having a predominant transverse orientation, and feeding a longitudinal carding machine with at least one second ply of non-woven fabric made of polyester fibers that have a predominant longitudinal orientation and melt at a lower temperature than the first and third plies;    arranging at least one net of glass fibers at least between one of said first and third plies with predominant transverse orientation and the second ply with predominant longitudinal orientation;    calendering said first, second, third plies and said at least one net at a softening temperature of said at least one ply with predominant longitudinal orientation, consolidating them and bonding them to said at least one glass fiber net, obtaining an assembly;    treating the assembly with resin and drying the assembly.    
     
     
         9 . The method according to  claim 8 , comprising, before the calendering step, the step of pre-needle punching the assembly enough to allow transport to the calendering machine.  
     
     
         10 . The method according to  claim 8 , wherein calendering is performed at approximately 210° C.  
     
     
         11 . A method for producing reinforced layered product based on non-woven fabric, comprising the steps of: 
 feeding a carding machine that is orientated longitudinally with respect to a direction of advancement of a product with at least one first ply and with at least one third ply made of non-woven fabric made of polyester fibers that have a predominant transverse orientation;    applying a layer of hot-melt adhesive to an inner side of one of said at least one first ply and said at least one third ply;    arranging between said at least one first ply and at least one third ply at least one glass fiber net;    calendering said first, second and third plies and said at least one net at a softening temperature of said hot-melt adhesive, consolidating them and bonding said at least one glass fiber network, obtaining an assembly;    resin-coating the assembly and drying the assembly.    
     
     
         12 . The method according to  claim 9 , comprising, before the calendering step, the step of pre-needle punching the assembly enough to allow transport to the calendering machine.  
     
     
         13 . The method according to  claim 9 , wherein calendering is performed at approximately 210° C.