Abstract: A method of coating a polymeric resinous thin film on the surface of a tubular braid reinforcing material, wherein a polymeric resinous coating material is spin coated on the surface of an annular braid, the coated braid is extruded into the air, and the coating material is coagulated in a coagulating bath, wherein the ratio of the spin coating feed ratio (Q) one the braid advancing speed (v) with respect to a unit outer diameter (D0) of the braid is represented by the formula k ? ( g ? / ? m 2 ) = Q ? ( g ? / ? min ) v ? ( m ? / ? min ) ? D 0 ? ( m ) within the range of 200 to 3,000 g/m2.

Abstract: The present invention relates to a braid-reinforced hollow fiber membrane. The hollow fiber membrane comprises a reinforcing material of a tubular braid and a polymer resinous thin film coated on the surface of the reinforcing material. The polymer resinous thin film has a skin layer with micro pores having a diameter in the range from 0.01 to 1 &mgr;m and an inner layer of a sponge structure with micro pores having a diameter less than 10 &mgr;m.