PRODUCTION OF AQUEOUS DISPERSION AND AQUEOUS SOLUTION OF WATER-SOLUBLE POLYMER

PURPOSE:To provide a stable aqueous dispersion which can be transferred with a pump or filtered with a filter-press, etc. and gives a completely dissolved clear solution when mixed with an alkaline liquid, by compounding a water-soluble polymeric substance treated with an aldehyde compound, a carboxylic acid, a polyhydric phenol and water. CONSTITUTION:The objective dispersion is obtained by compounding a water-soluble polymeric substance treated with an aldehyde compound, a carboxylic acid, a polyhydric phenol, and an aqueous medium. As an alternative method, a water-soluble polymeric substance is treated with an aldehyde compound and a carboxylic acid, and compounded with a polyhydric phenol and an aqueous medium. The carboxylic acid is formic acid or acetic acid, and its amount should be increased when the aqueous dispersion is to be stored for a long period. The addition of the carboxylic acid inhibits the scission of the acetal bond between the aldehyde and the water-soluble polymer, promotes the dissolution-delaying effect of the polyhydric phenol, elongates the dissolution time of the water-soluble polymeric substance, and retains undissolved state for a long period without producing agglomerates.