| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for producing a polyvinyl alcohol resin, by which impurities are efficiently removed with a small amount of cleaning solution. <P>SOLUTION: A polyvinyl alcohol obtained through a polymerization step (Step S1) and a saponification step (Step S2) is cleaned with a cleaning solution containing 1-40 pts.mass of methyl acetate, 50-98.9 pts.mass of methanol, and 0.1-10 pts.mass of water in a cleaning step (Step S3). At that time, the solid concentration of a slurry containing the cleaning solution is set to be 1-30 mass%. <P>COPYRIGHT: (C)2011,JPO&INPIT |
