| 摘要 |
A heat-adhesive composite fiber consisting of core portion (1) and sheath portion (2), the core portion being of the side-by-side type composite structure comprising two core components (1a, 1b) of different polypropylene base polymers at a composite ratio of 1:2 to 2:1, one of the core components having a Q value, expressed in terms of the weight-average molecular weight/the number-average molecular weight, equal to or higher than 6 and the other having a Q value equal to or lower than 5, and the sheath portion meeting at least the requirments that it should comprise a sheath component of a polyethylene base polymer having a melting point lower by at least 20 DEG C than the lower one of the melting points of the two core components, and it should cover the core portion in a proportion of 25 to 55 % by weight based on the total weight of it and the core portion. |
