Polyvinyl alcohol fibers having excellent water resistance and their production method (Polyvinyl alcohol fibers excellent in resistance to boiling water and process for production thereof)

摘要

A spinning yarn obtained by spinning a polyvinyl alcohol polymer solution is subjected to drawing at a total draw ratio of not less than 15 times to produce a polyvinyl alcohol fiber. A spinning yarn containing an acetal compound of an aliphatic dialdehyde having 6 or more carbon atoms as a cross-The crosslinking agent is hardly oxidized by the heat at the time of stretching at the time of fiber production and the crosslinking agent is less likely to be scattered during dry heat elongation, In addition, the crosslinking agent penetrates into the inside of the fiber to obtain a high strength, high moisture resistance, heat-resistant polyvinyl alcohol-based fiber which is sufficiently crosslinked not only on the fiber surface but also inside the fiber.