Laminate system for a durable controlled modulus flexible membrane

Abstract

A fabric system for producing at least a woven fabric of controlled modulus or elongation in the MD or warp axis, has a core layer which is the main structural element, and may have one or more woven cover fabrics adhesively bonded with an off axis configuration to one or both sides of the core layer. In a preferred embodiment the core fabric is covered with at least one off axis fabric on both sides. The cover fabrics may also have resin or film top layers laminated or coated on their outside surfaces, for mechanical performance or UV protection or both.

1 . A flexible laminate system with angularly distributed, controlled modulus threadlines comprising: 
 a flexible core layer with yarn spacing of greater than 15 epi and up to 30 epi in the MD, and having an elongation in the MD of less than 0.25 percent at 10 lbf/inch and less than 0.5 percent at 50 lbf/inch; and    at least one fabric cover layer oriented with its respective threadlines at a bias angle with respect to the threadlines of said core layer, said cover layer being bonded to said core layer and having a resin top coating applied thereto.    
   
   
       2 . The flexible laminate system of  claim 1 , said at least one fabric cover layer comprising at least two said fabric cover layers.  
   
   
       3 . The flexible laminate system of  claim 1 , said core layer having less than two percent crimp in the MD.  
   
   
       4 . The flexible laminate system of  claim 3 , said core layer having at least 21 epi in the CM and an elongation in the CM of not more than 0.5 percent at 10 lbf/inch.  
   
   
       5 . The flexible laminate system of  claim 4 , said core layer comprising fibers from among the group of fibers consisting of polyaromatic amide, polyethylene, Carbon, multifilament liquid crystal polymer, PBO, para-aramid, Polyester, PEN, aramid polymer, and Nylon or polyamide fiber.  
   
   
       6 . The flexible laminate system of  claim 5 , comprising a uniform angular distribution of the machine direction and cross machine threadlines of said core and cover layers.  
   
   
       7 . The flexible laminate system of  claim 6 , said cover layers having an uncoated air permeability of greater than 100 cfm/ft2 and less than 1000 cfm/ft2.  
   
   
       8 . The flexible laminate system of  claim 7 , said core layer comprising thermoplastic multifilament liquid crystal polymer yarn.  
   
   
       9 . The flexible laminate system of  claim 7 , said core layer comprising 1500 denier thermoplastic multifilament liquid crystal polymer yarn.  
   
   
       10 . The flexible laminate system of  claim 7 , said cover layer comprising polyester yarn configured at greater than 15×15 epi.  
   
   
       11 . The flexible laminate system of  claim 7 , said cover layer comprising 70 denier polyester yarn configured at 50×50 epi.  
   
   
       12 . The flexible laminate system of  claim 7 , an aliphatic urethane resin top coating applied to at least one said said cover layer.  
   
   
       13 . The flexible laminate system of  claim 10 , said core layer comprising thermoplastic mutlifilament liquid crystal polymer yarn and polyester yarn alternated in a modified weave pattern.  
   
   
       14 . The flexible laminate system of  claim 7 , further comprising defined inner and outer surfaces, and having at least one film top layer on the outer surface.  
   
   
       15 . The flexible laminate system of  claim 7 , comprising a core layer weave density of less than 50%.  
   
   
       16 . A flexible laminate system with angularly distributed, controlled modulus threadlines comprising: 
 a flexible core layer with yarn spacing up to 30 epi in the MD, elongation in the MD of less than 0.25 percent at 10 lbf/inch and less than 0.5 percent at 50 lbf/inch, and yarn spacing of at least 15 epi in the CM and elongation in the CM of not more than 0.5 percent at 10 lbf/inch,    said core layer comprising fibers from among the group of fibers consisting of polyaromatic amide, polyethylene, Carbon, multifilament liquid crystal polymer, PBO, para-aramid, Polyester, PEN, aramid polymer, and Nylon or polyamide fiber; and    at least two fabric cover layers comprising polyester yarn and oriented to said core layer with their respective threadlines at a bias angle with respect to the threadlines of said core layer, said cover layers being bonded to said core layer and having a resin top coating applied thereto, said layers of said laminate system being adhesively bonded together, said laminate system further comprising defined inner and outer surfaces, and having at least one film top layer bonded to said outer surface.    
   
   
       17 . The flexible laminate system of  claim 16 , comprising a core layer weave density of less than 50%.  
   
   
       18 . A flexible laminate system with angularly distributed, controlled modulus threadlines comprising: 
 a fabric core layer and at least two fabric cover layers, said core layer having less than two percent crimp in the MD and elongation in the MD of less than 0.25 percent at 10 lbf/inch, said core layer comprising thermoplastic multifilament liquid crystal polymer yarn and polyester yarn alternated in a modified weave pattern, and having at least 21 epi in the CM, with elongation in the CM of not more than 0.5 percent at 10 lbf/inch, said cover layers comprising a woven polyester yarn fabric of at least 50×50 epi with resin coating, cut and formed with a bias angle with respect to said core layer, a said cover layer adhesively bonded to each side of said core layer, and an aliphatic urethane resin top coating applied to each said cover layer.    
   
   
       19 . The flexible laminate system of  claim 18 , comprising a core layer weave density of less than 50%.  
   
   
       20 . The flexible laminate system of  claim 19 , comprising a core layer weave construction of at least 15 and up to 30 epi in the MD.  
   
   
       21 . The flexible laminate system of  claim 20 , said core layer having elongation of the MD at 50 lbf/inch of web of less than 0.5 percent.