SEPARATING MEMBRANE AND ITS PRODUCTION

• Main Authors: SUHARA GYOKKO, OKAMOTO TAKEHIKO, SHIGEHISA TAKAHIDE, DOHATA YOSHIZO, TOKOO MAKIO
• Format: Patent
• Language: English
• Published: 03.03.1998
• Edition: 6
• Subjects: PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SEPARATION; TRANSPORTING

PROBLEM TO BE SOLVED: To impart high pressure resistance to a separating membrane by an easy operation with high productivity without varying the performance by forming a film from a stock soln. contg. a vinyl alcohol polymer, washing the film and crosslinking the polymer by irradiation with electron beams. SOLUTION: A film is formed from a film forming stock soln. contg. a vinyl alcohol polymer, it is washed and the polymer is crosslinked by irradiation with electron beams to obtain the objective separating membrane. An ethylene- vinyl alcohol copolymer is suitable for use as the vinyl alcohol polymer as the material of the separating membrane used in the medical field because very little matter is leached from the polymer. At the time of irradiation with electron beams, a higher crosslinking effect is produced by irradiating the film in a wet state. It is therefore preferable that the film is washed to remove the solvent and the wet film is introduced into an irradiating device and irradiated with electron beams. The pref. water content of the film is about >=0.5wt.%.