To provide a polylactic acid fiber having biodegradability, light-weight and heat-insulating property, high hollowness and remarkably improved strength, abrasion resistance, etc., participating in durability, and provide a method for producing the polylactic acid fiber and a fiber structure for industrial material composed of the fiber.
The polylactic acid fiber is composed of a multifilament straight yarn and has a hollowness of 11-70%. The fiber structure for industrial material is composed of the polylactic acid fiber. The polylactic acid fiber having a hollowness of 11-70% is produced by a melt-spinning method enclosing the spun fiber with a heating tube and/or a heat-insulation tube having its upper end above the spinneret face by 0-15 cm and extending downward to a length of 5-100 cm to expose the spun fiber to a high-temperature atmosphere of 160-280°C.
NAKAMURA KOTA
FUTAI KATSUNORI
