PRODUCTION OF SEPARATING MEMBRANE

摘要

PURPOSE:To perform the compounding of an ultrathin membrane in the state of a high molecular soln. by feeding a volatile solvent soln. dissolved with a high molecular material at a definite velocity on the surface of a supporting liquid to form the thin membrane and then bringing an inactive perforated support into contact therewith and compounding them. CONSTITUTION:A high molecular soln. 3 consisting of both a high molecule forming a homogeneous membrane which has permeability and is not perforated and a volatile solvent is continuously fed at the definite velocity by a liquid feed pump on the surface of a supporting liquid 5. The high molecular soln. is immediately developed on the surface of the supporting liquid 5 and an ultrathin soln. membrane 11 is formed. The flow velocity of the extruded high molecular soln., the velocity of a winding-up roller 7 and the transfer velocity of the supporting liquid 5 decided by an auxiliary roller 10 can be arbitrarily controlled and thereby the formed ultrathin soln. membrane 11 can be made to the aimed thickness. The ultrathin soln. membrane 11 is transferred to a soft and inactive perforated support 8 which is fed by bringing the roller 7 into contact with the liquid surface and compounded. Thereafter the solvent is immediately evaporated and the membrane 11 is dried up and made into a unitary body.