The Investigation of Absorption and Scattering Mechanism of UV Radiation on Fading Behavior of Water Based Flexography Printing Inks

In this research the effect of the scaterring mechanism of titanium dioxide incorporated ink printing inks on the fading behaviour of such inks was studied. Investigation, It was shown that increasing the amount of titanium dioxide present in the ink formulation may increase the observed fading rate of prints from pigment based inks and reduce the fading rate of dye based inks. There is an optimum amount of titanium dioxide which when added to such formulations, protect the prints from fading. In addition the effect of the absorption mechanism of UV absorber content present in the overprint clearcoat, on fading was also evaluated. It has been shown that for water-based inks, the fading rate of subsequent prints were reduced for overprint clearcoats containing organic and inorganic UV absorber.the synergistic effect of both mechanisms on fading was observed.