Light weight trauma reducing body armor

Abstract

A multilayer laminated structure particularly useful as soft body armor has layers of aramid fabric, thermoplastic sheet or polyolefinic fabric bonded together using a polyolefinic adhesive. The stack of layers is consolidated under heat and pressure to provide trauma packs having low weight and low trauma as required by Indian body armor standards.

We claim: 
     
         1 . A trauma reducing pack, comprising
 (i) at least one first layer of aramid fabric comprising yarns having a tensile strength of at least 900 MPa and having a linear density of 444-1111 dtex, the fabric having an inner and outer surface.   (ii) at least one second layer of a thermoplastic sheet having a tensile strength of at least 60 MPa or a thermoplastic nonwoven fabric comprising yarns having a tensile strength of at least 900 MPa, the sheet or nonwoven fabric having an inner and outer surface, and   (ii) a polyolefinic adhesive having a melting point of from 70-150° C.,   wherein the at least one first layer and the at least one second layer are bonded together by means of the polyolefinic adhesive.   
     
     
         2 . The trauma reducing pack of  claim 1 , wherein the polyolefinic adhesive is an ethylene copolymer or a grafted polyolefin. 
     
     
         3 . The trauma reducing pack of  claim 1 , wherein the fabric is woven, nonwoven, unidirectional or multidirectional. 
     
     
         4 . The trauma reducing pack of  claim 1 , wherein the thermoplastic sheet is polycarbonate, acrylonitrile butadiene styrene copolymer, ethylene-methacrylic acid copolymer, bidirectional polyolefinic tape or combinations thereof. 
     
     
         5 . The trauma pack of  claim 1 , wherein the thermoplastic nonwoven fabric is a spunbond nonwoven of polyolefin. 
     
     
         6 . The trauma pack of  claim 5 , wherein the polyolefin is a polyethylene, polypropylene, polybutene, or a blend or copolymer thereof. 
     
     
         7 . The trauma pack of  claim 4 , wherein the multidirectional polyolefinic tape is a cross-plied non-fibrous ultra-high molecular weight polyethylene (UHMWPE) tape. 
     
     
         8 . The trauma pack of  claim 1  having an aerial density of less than 1000 g/m 2 . 
     
     
         9 . The trauma pack of  claim 1  comprising:
 (i) from 1 to 4 layers of aramid fabric, 
 (ii) from 1 to 5 layers of thermoplastic sheet, 
 (iii) from 1 to 3 layers of nonwoven fabric, and 
 (iv) from 1 to 4 layers of polyolefinic adhesive. 
 
     
     
         10 . A body armor comprising at least one trauma pack according to  claim 1 .