Patent ID: 7468335
Filing Date: 2008-12-23
Classification: C08G,D01D,D01F,D04H,Y10T

Abstract:
1. A meltblown web comprising interbonded fibers extruded through a die with multiple orifices and attenuated by gas at a predetermined velocity to an average draw ratio of above 50, up to 250, said fibers including a thermoplastic polyester poly (butylene terephthalate) based copolymer which comprises: A) an aromatic dicarboxylic acid component or derivative thereof, which is selected from group consisting of terephthalic acid and its derivatives; and B) at least two diol components, including: wherein the copolymer composition is selected and formation of the meltblown web is controlled such that the melt-blown web exhibits at least one of the following attributes: 1) a machine direction (MD) strength index in the range of from 3 to 15; 2) an MD/CD tensile strength ratio in the range of from 0.5 to 1.5; or 3) a mean fiber diameter in the range of from 0.5 to 3.0 μm.