Abdollah Alizadeh

Acrylic styrene latex was used in combination with nanoclay at two different loading levels and calcium carbonate at four loading levels to improve printability characteristics of mechanical printing paper. SEM micrographs indicated filling of the voids and covering of the printing paper surface. Different rheological behavior of the coating that contained two coating pigments, in addition to their different viscosity, was clearly evident. Calcium carbonate was more advantageous due to the reduction in pumping costs. Paper coating improved roughness and air-permeability properties. Water absorption of the coated paper was decreased by at least 50% which significantly affects the dimensional stability of the paper during web offset printing. Specular gloss and print density were significantly increased at a 1% probability level by coating the surface of the paper. Contrary to the control sample, picking of the paper (which is of great importance after printing and for linting on the printing cylinder) did not occur.