Method for hydrophilizing polyvinylidene fluoride-based porous separation membrane

The present invention pertains to a method for hydrophilizing a polyvinylidene fluoride-based porous separation membrane, the method comprising a step in which a polyvinylidene fluoride-based porous separation membrane is brought into contact with a hydrophilizing agent and then brought into contact with water, the separation membrane comprising a polyvinylidene fluoride-based resin and having a surface average pore diameter of 1-20 nm and a surface contact angle with water of 80-110 DEG. The hydrophilizing agent contains a surfactant, and has a surface tension of 30 to 45 mN/m and a density of 1.000 to 1.010 g/cm3. 本发明涉及聚偏二氟乙烯系多孔质分离膜的亲水化方法，其具有使聚偏二氟乙烯系多孔质分离膜与亲水化剂接触后，与水接触的步骤，前述分离膜包含聚偏二氟乙烯系树脂，表面的平均孔径为1~20nm，表面与水的接触角为80~110°，前述亲水化剂包含表面活性剂，表面张力为30~45mN/m，密度为1.000~1.010g/cm3。