PRODUCTION OF COMPOSITE HOLLOW FIBER MEMBRANE

摘要

PURPOSE:To uniformly cover and form an ultrathin membrane of 0.01-0.5mu on the surface of a fibrous material by continuously running a support consisting of a hollow fibrous porous membrane having constant pore diameter in such a state that is penetrates a water-surface developing membrane and shifting the water-surface developing membrane on the surface of this support. CONSTITUTION:After forming a water-surface developing membrane 5 by developing a polymer soln. discharged through a feed port 3 thereof on the water surface 12, the membrane 5 is stored in a storage tank 7 of the polymer via a conveyor 4 and reused. Then a hollow fibrous porous membrane 6 having <=2,500Angstrom maximum pore diameter is run at the position wherein the membrane 5 positioned in the intermediate part between the feed port 3 and the conveyor 4 desirably has fluidity to a water layer side from the opposite side of the water layer in such a state that the porous membrane 6 penetrates the membrane 5 and this membrane 5 is shifted on the surface of the porous membrane 6. This porous membrane 6 covered in such a way is fed to the outside of a water-surface developing apparatus with a fiber feeding roller 13.