Improvement of Mechanical and Optical Properties of Mechanical Printing Paper after Coating with Nanoclay and Precipitated Calcium Carbonate

This study was conducted to investigate the low weight coating (LWC) effects on mechanical and optical properties of printing papers produced by Mazandaran Wood and Paper Industries Co. (MWPI). Two mineral pigments including nanoclay and precipitated calcium carbonate (PCC) were applied by blade coating method in different weight percentages of latex. Surface structure of coated paper was characterized by atomic force microscopy (AFM). Also، mechanical and optical properties of coated paper and control were measured. Comparison of the characteristics showed that surface of coated paper with nanoclay had better uniformity and smoothness than PCC due to higher specific area and plate form shape. There were no significant differences among the paper strength except tensile stiffness. Yellowness of the LWC paper with nanoclay decreased by approximately 20% compared to the control، whereas there were no significant differences among of brightness and opacity of LWC paper and control.