| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method of manufacturing polyvinyl acetal with a high degree of polymerization and little residual inorganic ion components causing less reaction inhibition, less coloring and progress of saponification reaction; and to provide polyvinyl acetal manufactured using the method of manufacturing polyvinyl acetal. <P>SOLUTION: This method includes: a step 1 in which polyvinyl alcohol is brought into contact with hydrogen peroxide to achieve a low degree of polymerization; and a step 2 in which the polyvinyl alcohol with a low degree of polymeralization made in the step 1 is brought into reaction with aldehyde to be acetalized in a system under acidic conditions using an acid catalyst. In the step 1, ultraviolet light of a wavelength of 200-300 nm is irradiated. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
