| 摘要 |
Disclosed is a polyethylene terephthalate untwisted multifilament which satisfies the following requirements (A), (B), (C) and (D); (A) the intrinsic viscosity [IV] is 0.97 to 1.15; (B) the amorphous orientation function [fa] is not larger than 0.55; (C) the tenacity [T] (g/d), the shrinkage [ DELTA S] (%) as measured after standing in dry air at 150 DEG C for 30 minutes, the medium elongation [ME] (%) under a load of 4.5 g/d, and the dimensional stability index [Y] expressed by the formula: Y= ME<0.81> + DELTA S + 1.32 are within ranges defined by the following formulae (a), (b), (c), (d) and (e): <TABLE> and <TABLE> and (d) the elongation at break is at least 11% and the product of the tenacity and elongation, which is defined by: [tenacity (g/d) at break] x 2ROOT elongation (%) at break, is 30 to 36. |
