| 摘要 |
A polyethylene naphthalate fiber of the present invention comprises a naphthalate-based copolyester in which at least 85 mol % or more of the total of recurring units is an ethylene 2,6-naphthalate unit, and it is obtained by copolymerizing an alkylene oxide adduct of a divalent phenol expressed by the following general formula (I) in an amount of 1 to 15 mol % as a part of the diol component. H-(OA)m-O-Ar-O-(AO)n-H In the formula, A expresses an alkylene group having a carbon number of 2 to 4, m and n are same as or different from each other, and each express an integer of 1 to 5, and Ar expresses a p-phenylene group, an m-phenylene group or a group of the following general formula (II). -Ph-X-Ph- In the formula, Ph expresses a p-phenylene group, and X expresses a 2,2-propylene group, a sulfone group, a methylene group, an oxygen atom or a sulfur atom. This fiber has high retention ratios of tensile strength and knot strength, and is excellent in durability, and the fiber is suited for applications such as a dryer canvas for papermaking which is used under severe conditions in which especially wet heat treatments and dry heat treatments are repeated. |
