The invention provides a polyvinyl acetal having a degree of acetalization of from 45 to 80 mol%, which is obtained through acetalization of a polyvinyl alcohol having a degree of polymerization of from 30 to 1000 and a degree of hydrolysis of from 80.0 to 99.99 mol% and having a specific amount of an ionic group bonded to the terminal thereof via a sulfido bond. The polyvinyl acetal of the invention is useful for binders for ceramic forming and for binders for ink or paint.
本发明提供了一种聚
乙烯醇缩醛,其
缩醛度为 45 至 80 摩尔%,它是通过
缩醛聚
乙烯醇而得,聚
乙烯醇的聚合度为 30 至 1000,
水解度为 80.0 至 99.99 摩尔%,并有一定量的离子基团通过亚
硫酰基键与其末端结合。本发明的聚
乙烯醇缩醛可用于陶瓷成型粘合剂和油墨或涂料粘合剂。