| 摘要 |
PROBLEM TO BE SOLVED: To provide a sea-island type composite fiber which comprises polylactic acid and polyglycolic acid, is excellent in handleability and process passability, and has small variation of biodegradability, and to provide a method for efficiently producing the sea-island type composite fiber.SOLUTION: A sea-island type composite fiber comprises polylactic acid and polyglycolic acid, has a single yarn fineness of 50 dtex or less, and has a U%H of less than 2.5%. In a sea-island type composite fiber production method, a molten mixture of polylactic acid and polyglycolic acid is subjected to melt spinning using a spinneret satisfying following conditions. D1 is 0.05-1.0 mm, D2 is 0.5-5.0 mm, and D2/D1 is 5-50 (D1 is a diameter of a minimum part of a discharge hole; and D2 is a diameter of a discharge surface of a discharge hole). |
