INHIBITION OF LIGHT-INDUCED YELLOWING OF HIGH-YIELD PULP BY SODIUM HYDROXYMETHYLPHOSPHINATE

Sodium hydroxymethylphosphinate was prepared from hypophosphorous acid and formaldehyde. Characterization of this compound and application t o high-yield bleached chemithermomechanical pulps as a potential brigh tness stabilizer are described. The results show that sodium hydroxyme thylphosphinate has several desirable characteristics; it is water-sol uble, colourless, odourless and stable in storage and can inhibit the light-induced yellowing of high-yield pulp to a moderate extent. The i nhibition of light-induced yellowing of chemithermomechanical pulp han dsheets impregnated with sodium hydroxymethylphosphinate was character ized by UV-visible diffuse reflectance spectroscopy and spectrofluorim etry.