POLYVINYL ALCOHOL AND PAPER COATING AGENT CONTAINING SAME

摘要

A polyvinyl alcohol in which the degree of saponification is 50-99.99 mol%, the viscosity-average degree of polymerization is 200-5000, and the alkali metal salt content in a carboxylic acid is 0.5% by mass or less in terms of the mass of the alkali metal, the peak top molecular weight (A) measured by a differential refractometer and the peak top molecular weight (B) measured by an absorption detector (measurement wavelength: 280 nm) satisfying formula (1) ((A - B)/A < 0.75) when the polyvinyl alcohol heated for three hours at 120°C is measured by gel permeation chromatography, and the absorbance at the peak top molecular weight (B) being 0.25×10-3 to 3.00×10-3. A polyvinyl alcohol is thereby provided having minimal heating-induced discoloration and excellent effects for enhancing water dispersibility of organic particles or inorganic particles.