METHOD FOR PRODUCING FIBER-REINFORCED POLYVINYLIDENE FLUORIDE POROUS HOLLOW FIBER MEMBRANE

PROBLEM TO BE SOLVED: To provide a method for producing a porous hollow fiber membrane which, without causing a trouble, such as cracking, in the porous hollow fiber membrane obtained even when a spinning speed is increased, improves load resistance and fatigue resistance, and provides high permeation characteristics, and which can inhibit the breaking of the porous hollow fiber membrane caused by a high flow rate of fluid, such as gas or liquid, or the breaking thereof caused by fatigue.SOLUTION: A method for producing a fiber-reinforced polyvinylidene fluoride porous hollow fiber membrane comprises: allowing a cylindrical braid to pass through the inside of the inner nozzle of a double annular spinning nozzle; applying a membrane-forming stock solution discharged from the outer nozzle of the double annular spinning nozzle to the outer surface of the cylindrical braid which has passed through the inner nozzle of the double annular spinning nozzle to impregnate it therein, and then coagulating it in a coagulation liquid; and carrying out winding onto a winder, thereby producing the fiber-reinforced polyvinylidene fluoride porous hollow fiber membrane. In the method, as the cylindrical braid, there is used a cylindrical braid having a braid density of 70/inch or more, or having a yarn fineness of 280 decitex or more and 36 or more filaments.SELECTED DRAWING: Figure 2 【課題】紡糸速度を速くした場合にも得られる多孔質中空糸膜に割れなどの不具合を発生させることなく、耐荷重性、耐疲労性を向上せしめるとともに、高い透過特性を有し、高流量の気体あるいは液体などの流体による多孔質中空糸膜の破断あるいは疲労による破断を抑制しうる多孔質中空糸膜の製造方法を提供する。【解決手段】円筒状組紐を二重環状紡糸ノズルの内側ノズル内を通過させ、二重環状紡糸ノズルの内側ノズルを通過した円筒状組紐の外表面に二重環状紡糸ノズルの外側ノズルから吐出させた製膜原液を塗布し、含浸させた後、凝固液中で凝固させ、巻取機への巻取りが行われて製造される繊維強化ポリフッ化ビニリデン多孔質中空糸膜の製造方法において、円筒状組紐として、編み密度が70／インチ以上、あるいは糸繊度280デシテックス以上かつ36フィラメント以上のものを用いる。【選択図】図２