Influence of Tack Reducer and Varnish on the Rheological Behavior of Offset Inks

The rheology behavior of the offset ink has strong contact with its printability. Tack reducer and varnish are often used to adjust the tack volume and viscosity of the ink. In order to study the influence of the variation of both tack volume and viscosity of the ink on the rheology behavior, tack reducer and varnish are used to adjust the tack volume and viscosity of the ink, the influence of the volume on the tack volume and viscosity are obtained and also the influence degree on rheology behavior by variation of the tack volume and viscosity. The results indicate that: the tack volume of ink decreases with the increasing of the tack reducer and the viscosity is the same; the viscosity decreases with the increasing of the varnish and the tack volume is also descended. Both the tack reducer and the varnish can change the tack volume and the viscosity, but the degree is different. The volume of the tack reducer and the varnish also has certain influence on the thixotropic and the dynamic viscoelastic of the ink.