Process for producing sea-island-type composite spun fiber

摘要

The method of producing an islands-in-sea type composite spun fiber having an island component diameter of 1 µm or less according to the present invention comprises drawing (superdrawing) with a total draw ratio of from 5 to 100 an undrawn islands-in-sea type composite spun fiber having been prepared by spinning at a spinning speed of from 100 to 1,000 m/min, at temperatures higher than the glass transition points of both the polymer forming the sea component and the polymer forming the island components of the composite spun fiber.