摘要 |
In a method for producing hollow fiber membranes which comprises melt kneading a mixture comprising polyvinylidene fluoride and an organic liquid or a mixture comprising polyvinylidene fluoride, an organic liquid and an inorganic fine powder, extruding the kneaded mixture to form hollow fibers, and extracting the organic liquid or the organic liquid and the inorganic fine powder from the hollow fibers, which includes the steps of drawing the hollow fibers before or after termination of the extraction and then shrinking the fibers. According to this method, it is possible to stably produce hollow fiber membranes having dense pores and having a high water permeation performance, excellent endurance and stain resistance, and which are suitable for filtration uses such as removal of turbidity of water. <IMAGE> |