Chitosan as a Surface Sizing Agent for Offset Printing Paper

Abstract

The biopolymer chitosan has been shown to improve the surface properties of paper for offset printing. The quality of the sized paper was investigated after treatment with chitosan of different molecular weights and different concentrations as well as in a blend with oxidised starch. The results were compared with the sizing quality of polyvinyl alcohol and oxidised starch. It was found that the molecular weight and concentration of the chitosan influenced the sizing quality. Blending of oxidised starch with a small quantity of chitosan significantly improved the sizing quality of the former. It was concluded that the chitosansized paper was superior for offset printing compared to paper sized with either oxidised starch or polyvinyl alcohol.