Effect of Surface Binder Content on Print Density and Ink Receptivity of Coated Paper, 1997 Advanced Coating Fundamentals Symposium Proceedings

The effect of binder content in the coating surface on print density and ink receptivity of model coated papers has been investigated, in order to better understand the relations between uneven binder migration and print density variations in offset printing. For model coated papers with a similar surface finish, the print density was solely determined by the amount of ink deposited, suggesting that print density variations are caused by uneven ink transfer in the printing nips. For coatings prepared with an identical formulation, more ink was transferred to the coatings with a lower surface binder content, providing further evidence that uneven binder migration causes uneven ink transfer, leading to print density variations. In addition, we have found, as expected, that binder content in the coating surface depends on both binder addition level in the coating colour formulation and on base stock absorbency. This turther indicates the importance of controlling uniformity of base sheet absorbency in preventing print mottle on coated papers.

*PT lndah Kiat Pulp & Paper Corp., lndonesia