Patent ID: 6913720

Claim:
A method of manufacturing a non-woven fabric comprising 75 to 95% by weight polypropylene based fibers, said polypropylene based fibers comprising about 80 to 99% by weight polypropylene and 1 to 20% by weight of a heat stabilizer, and 5 to 25% by weight polyester based fibers, said polyester based fibers comprising 80 to 100% by weight polyester and 0 to 20% by weight of a flame retardant, said fabric being manufactured by: admixing staple polypropylene based fibers and staple polyester based fibers in an amount of 75 to 95% by weight polypropylene based fibers and 5 to 25% by weight polyester based fibers, carding the admixed fibers by a textile card to form a mat aligned in a processing direction, processing the mat in the processing direction through a main loom with a needle penetration of between about 3 and 12 mm, hot calendaring the processed mat at a temperature of about 250 to 400° F. and a pressure of between about 700 and 1200 psi on one first side only.