Patent ID: 6312806
Filing Date: 2001-11-06
Classification: B60R,D01F,D02J,D03D,D10B,Y10T

Abstract:
Yarn having a force-displacement profile such that:(a) when said yarn is subjected to an initial barrier stress of from about 0.2 gram/denier to less than or equal to about 1.4 grams/denier, said yarn elongates to less than 3 percent and the initial modulus ranges from about 20 grams/denier to about 150 grams/denier;(b) upon subjecting said yarn to greater than said initial barrier stress and less than or equal to 1.8 grams/denier, said yarn elongates further to at least about 10 percent and the energy absorbed from 0 to the elongation at 1.8 grams/denier is at least about 0.0008 Joule/denier.multidot.meter; and(c) upon subjecting said yarn to greater than 1.8 grams/denier, the modulus increases sharply and said yarn elongates further until said yarn breaks at a tensile strength of at least about 5 grams/denier, wherein said yarn comprises a multiplicity of fibers, all of said fibers have substantially the same force-displacement profile, are made from polymers having a glass transition temperature in the range from about -40.degree. C. to about +70.degree. C., are not made from polybutylene terephthalate homopolymer, and are made from block copolymer comprising(i) at least one first block of polyester wherein said first block is made from an aromatic polyester and has an intrinsic viscosity of at least about 0.6 deciliter/gram as measured in a 60/40 by weight mixture of phenol and tetrachloroethane and(ii) at least one second block of polyester wherein said second block is made from lactone monomer.