Process for making a sized multifilament yarn of an aromatic polyamide

摘要

A multifilament yarn of an aromatic polyamide, in particular poly-p- phenylene terephthalamide, having a tenacity of at least 15 cN/dtex and an initial modulus of at least 400 cN/dtex is provided with a water- soluble size, the filaments of the yarn having a cohesion corresponding to a Manra number not higher than 40. The yarn is made by subjecting a non-sized yarn having a moisture content which is lower than its equilibrium moisture content, while under a tension of at most 0.25 cN/dtex, to a continuous wetting treatment with an aqueous solution of a size and subsequently winding the treated yarn into a yarn package. The yarn package contains a single continuous length of the sized yarn. The sized yarn is suitable as warp and weft yarn in the weaving industry.