PURPOSE: To obtain a porous membrane having a large pore size which is useful as a blood-treating membrane, etc., by immersing a soln. of a cellulose derivative in a coagulating agent having a specified coagulation value range and contg. an org. solvent which is a non-solvent for said cellulose derivative.
CONSTITUTION: A soln. obtd. by dissolving a cellulose derivative in a solvent, is immersed in a coagulating agent having a coagulation value of 40W250 and contg. at least 60wt% org. solvent, such as methanol or benzene, which is a non-solvent for the above cellulose derivative, whereby the cellulose derivative is coagulated to produce a uniform porous membrane having an average pore size of 0.05W20μ. Particularly, when a mixture of cellulose diacetate having an acetyl value of 52% or above and cellulose triacetate having an acetyl value of 60% or above in a weight ratio of 1/14W10/5, is used as a cellulose derivative, a porous membrane havnig large porosity and high mechanical strength can be obtained.
USE: Sterile water-treating membrane, etc.
| WO/2018/186141 | METHOD FOR PRODUCING POROUS BODY |
| JP6831051 | Improvements in and related to polymer membranes |
YAMAMORI HISAYOSHI
MATSUNAKA MITSUHIRO
HIRAI TAKAYUKI
