| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an island-in-sea type conjugated cross-section fiber in which peeling of a composite interface may be suppressed and fluff, thread breakage and the like may be largely improved, and to provide an extra fine polyamide fiber obtained by dissolving and removing polyester included in the island-in-sea type conjugated cross-section fiber. <P>SOLUTION: An easily alkali soluble polyester comprises: a principal repeating unit of ethylene terephthalate; an isophthalic acid component having a metal sulfonate group of 2.0 to 5.5 mol% based on the whole acid component; and an adipic acid component of 3.0 to 6.0 mol% based on the whole acid component. An island-in-sea type conjugated cross-section fiber comprises: the easily alkali soluble polyester including 3 to 10 ppm of a polyester-soluble titanium compound in terms of titanium element and 5 to 40 ppm of a phosphorus compound in terms of phosphorus element as a sea component; and a polyamide as an island component. <P>COPYRIGHT: (C)2012,JPO&INPIT |
