| 摘要 |
PURPOSE: To produce a porous inorg. membrane free of such defects as pinholes and cracks by using a colloidal particle formed from a sol wherein a metal polyoxide and the colloidal particle are dispersed and obtained by the hydrolysis of urea as a compositional component. CONSTITUTION: The coating soln. for forming an inorg. porous membrane consists of a sol wherein >=1 kind among the colloidal particles of metal polyoxide and metal polyhydroxide and dispersed, and the colloidal particle is obtained by the hydrolysis of urea in a metallic salt compd. soln. contg. urea. The colloidal particle has <=10nm diameter. Meanwhile, the inorg. porous membrane is formed by subjecting the coating soln. to gelation, drying the gel to form a film and calcining the film. The average pore diameter of the calcined body is preferably controlled to <=0.1μm and the amt. of pure water to be permeated to <=1×10<-4> l/min.M<2> Pa. The coating soln. is subjected to gelation, dried and calcined to produce the inorg. porous membrane. |
