| 摘要 |
PURPOSE:To continuously obtain a fluid separation membrane with less infiltration into a porous hollow yarn and having excellent permeability by supplying a soln. of a membrane forming material in an org. solvent over the surface of a liq. incompatible with the soln. to form a thin layer, and bringing the thin layer into contact with the hollow yarn. CONSTITUTION:An optional polymer capable of forming a substantially non- porous film by a casting method can be exemplified as the membrane forming material. The material is dissolved in a solvent having a positive expansion coefficient, capable of uniformly dissolving the material, and having appropriate volatility. The concn. is preferably controlled to <=10wt%. The membrane material soln. 5 is supplied over a solvent 6 incompatible with the soln., forming a distinct interface, not dissolving the membrane material, and having high surface tension. The membrane material soln. is spread, and a thin layer is formed. The hollow yarn 8 is continuously supplied into the thin layer and brought into contact with the layer. Consequently, the infiltration of the active layer material into the porous hollow yarn is reduced, and a separation membrane having excellent permeability can be continuously obtained. |
