| abstract |
Disclosed is a dispersant using a modified polyvinyl alcohol having a specific unsaturated double. A modified polyvinyl alcohol having a saponification degree of 20 to 60% and an average polymerization degree of 100 to 1000, containing a bond unit having an unsaturated double bond represented by the following formula in the molecular main chain. (Y1 represents carboxylic acid, carboxylic acid ester, carboxylic acid metal salt or H.) [Selection figure] None |