Patent ID: 6235657
Filing Date: 2001-05-22
Classification: B32B,D04H,Y10T

Abstract:
A laminate which exhibits improved dimensional stability combined with no tendency to delaminate and is capable of being bituminized in the absence of delamination to form a uniform roofing sheet of enhanced reliability comprising at least two layers of spunbonded web made of continuous synthetic fibers composed of melt spinnable polymer materials and at least one laid structure layer of reinforcing yarns formed from mutually angled sets of parallel reinforcing yarns fixed to one another at their crossover points and wherein the angle between the crossing sets of reinforcing yarns is between 10.degree. and 90.degree. and the laid structure layer is disposed between two layers of the spunbonded web, the laid structure layer having a thread density of 0.5 to 3 threads/cm and wherein the spunbonded and laid structure layers are joined together by needling at 20 to 70 stitches/cm.sup.2 in the absence of the use of a thermoplastic adhesive to join said layers of spunbonded web and said laid structure layer wherein said thermoplastic adhesive is rendered functional through the simultaneous application of heat and pressure.