MONOFILAMENT AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To obtain a monofilament having practically sufficient mechanical strength and excellent processability, useful for surgical suture, or the like, by compounding a polylactic acid-based polymer with an aliphatic polyester except the polylactic acid in a specific ratio to give a material, extrusion molding the material and drawing and processing the extrusion molded material at a prescribed temperature. SOLUTION: (A) A polylactic acid-based polymer as a main component is compounded with (B) an aliphatic polyester comprising two or more kinds of aliphatic polyesters except the polylactic acid polymer, composed of an aliphatic carboxylic acid component and an aliphatic alcohol component and/or an aliphatic hydroxycarboxylic acid component in the compounding ratio of the component AB of 95/5 to 61/39 to give a material, which is extrusion molded, drawn and processed at a temperature equal to or higher than the melting point of the aliphatic polyester except the polylactic acid at 3-9 times draw ratio to give the objective monofilament in which the component A is orientated but the component B is nonoriented. The surface of the monofilament is further coated with a polymer material such as a polylactic acid, a polyurethane, or the like. A string for racket, surgical suture, fishing line, string for musical instrument are preferably produced from the monofilament.